DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsumura, Yukihiko; Nuessle, F.W.; Antal, M.J. Jr.

Recently, carbonaceous materials were proved to be effective catalysts for hazardous waste decomposition in supercritical water. Gasification of the carbonaceous catalyst itself is also expected, however, under supercritical conditions. Thus, it is essential to determine the gasification rate of the carbonaceous materials during this process to determine the active lifetime of the catalysts. For this purpose, the gasification characteristics of granular coconut shell activated carbon in supercritical water alone (600-650{degrees}C, 25.5-34.5 MPa) were investigated. The gasification rate at subatmospheric pressure agreed well with the gasification rate at supercritical conditions, indicating the same reaction mechanism. Methane generation under these conditions ismore » via pyrolysis, and thus is not affected by the water pressure. An iodine number increase of 25% was observed as a result of the supercritical water gasification.« less

Method for Hot Real-Time Sampling of Gasification Products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pomeroy, Marc D

The Thermochemical Process Development Unit (TCPDU) at the National Renewable Energy Laboratory (NREL) is a highly instrumented half-ton/day pilot scale plant capable of demonstrating industrially relevant thermochemical technologies from lignocellulosic biomass conversion, including gasification. Gasification creates primarily Syngas (a mixture of Hydrogen and Carbon Monoxide) that can be utilized with synthesis catalysts to form transportation fuels and other valuable chemicals. Biomass derived gasification products are a very complex mixture of chemical components that typically contain Sulfur and Nitrogen species that can act as catalysis poisons for tar reforming and synthesis catalysts. Real-time hot online sampling techniques, such as Molecular Beammore » Mass Spectrometry (MBMS), and Gas Chromatographs with Sulfur and Nitrogen specific detectors can provide real-time analysis providing operational indicators for performance. Sampling typically requires coated sampling lines to minimize trace sulfur interactions with steel surfaces. Other materials used inline have also shown conversion of sulfur species into new components and must be minimized. Sample line Residence time within the sampling lines must also be kept to a minimum to reduce further reaction chemistries. Solids from ash and char contribute to plugging and must be filtered at temperature. Experience at NREL has shown several key factors to consider when designing and installing an analytical sampling system for biomass gasification products. They include minimizing sampling distance, effective filtering as close to source as possible, proper line sizing, proper line materials or coatings, even heating of all components, minimizing pressure drops, and additional filtering or traps after pressure drops.« less

Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge. Part 2: Evaluation of ash materials as phosphorus fertilizer.

PubMed

Thomsen, Tobias Pape; Hauggaard-Nielsen, Henrik; Gøbel, Benny; Stoholm, Peder; Ahrenfeldt, Jesper; Henriksen, Ulrik B; Müller-Stöver, Dorette Sophie

2017-08-01

The study is part 2 of 2 in an investigation of gasification and co-gasification of municipal sewage sludge in low temperature gasifiers. In this work, solid residuals from thermal gasification and co-gasification of municipal sewage sludge were investigated for their potential use as fertilizer. Ashes from five different low temperature circulating fluidized bed (LT-CFB) gasification campaigns including two mono-sludge campaigns, two sludge/straw mixed fuels campaigns and a straw reference campaign were compared. Experiments were conducted on two different LT-CFBs with thermal capacities of 100kW and 6MW, respectively. The assessment included: (i) Elemental composition and recovery of key elements and heavy metals; (ii) content of total carbon (C) and total nitrogen (N); (iii) pH; (iv) water extractability of phosphorus after incubation in soil; and (v) plant phosphorus response measured in a pot experiment with the most promising ash material. Co-gasification of straw and sludge in LT-CFB gasifiers produced ashes with a high content of recalcitrant C, phosphorus (P) and potassium (K), a low content of heavy metals (especially cadmium) and an improved plant P availability compared to the mono-sludge ashes, thereby showing the best fertilizer qualities among all assessed materials. It was also found that bottom ashes from the char reactor contained even less heavy metals than cyclone ashes. It is concluded that LT-CFB gasification and co-gasification is a highly effective way to purify and sanitize sewage sludge for subsequent use in agricultural systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gasification Slag and the Mechanisms by Which Phosphorous Additions Reduce Slag Wear and Corrosion in High Cr2O3 Refractories

NASA Astrophysics Data System (ADS)

Bennett, James; Nakano, Anna; Nakano, Jinichiro; Thomas, Hugh

Gasification is a high-temperature/high-pressure process that converts carbonaceous materials such as coal and/or petcoke into CO and H2, feedstock materials used in power generation and chemical production. Gasification is considered an important technology because of its high process efficiency and the ability to capture environmental pollutants such as CO2, SO3 and Hg. Ash impurities in the carbon feedstock materials melt and coalesce during gasification (1325-1575 °C), becoming slag that attaches to and flows down the gasifier sidewall, corroding and eroding the high Cr2O3 refractory liner used to protect the gasification chamber. Phosphate additions to high Cr2O3 refractory have been found to alter slag/refractory interactions and dramatically reduce refractory wear by the following mechanisms: a) spinel formation, b) slag chemistry changes, c) two phase liquid formation, and d) oxidation state changes. The mechanisms and how they work together to impact material wear/corrosion will be discussed.

Application of CaO-Based Bed Material for Dual Fluidized Bed Steam Biomass Gasification

NASA Astrophysics Data System (ADS)

Koppatz, S.; Pfeifer, C.; Kreuzeder, A.; Soukup, G.; Hofbauer, H.

Gasification of biomass is a suitable option for decentralized energy supply based on renewable sources in the range of up to 50 MW fuel input. The paper presents the dual fluidized bed (DFB) steam gasification process, which is applied to generate high quality and nitrogen-free product gas. Essential part of the DFB process is the bed material used in the fluidized reactors, which has significant impact on the product gas quality. By the use of catalytically active bed materials the performance of the overall process is increased, since the bed material favors reactions of the steam gasification. In particular, tar reforming reactions are favored. Within the paper, the pilot plant based on the DFB process with 100kW fuel input at Vienna University of Technology, Austria is presented. Actual investigations with focus on CaO-based bed materials (limestone) as well as with natural olivine as bed material were carried out at the pilot plant. The application of CaO-based bed material shows mainly decreased tar content in the product gas in contrast to experiments with olivine as bed material. The paper presents the results of steam gasification experiments with limestone and olivine, whereby the product gas composition as well as the tar content and the tar composition are outlined.

Coal gasification systems engineering and analysis. Appendix A: Coal gasification catalog

NASA Technical Reports Server (NTRS)

1980-01-01

The scope of work in preparing the Coal Gasification Data Catalog included the following subtasks: (1) candidate system subsystem definition, (2) raw materials analysis, (3) market analysis for by-products, (4) alternate products analysis, (5) preliminary integrated facility requirements. Definition of candidate systems/subsystems includes the identity of and alternates for each process unit, raw material requirements, and the cost and design drivers for each process design.

Molecular characterization of biochars and their influence on microbiological properties of soil.

PubMed

Chintala, Rajesh; Schumacher, Thomas E; Kumar, Sandeep; Malo, Douglas D; Rice, James A; Bleakley, Bruce; Chilom, Gabriela; Clay, David E; Julson, James L; Papiernik, Sharon K; Gu, Zheng Rong

2014-08-30

The tentative connection between the biochar surface chemical properties and their influence on microbially mediated mineralization of C, N, and S with the help of enzymes is not well established. This study was designed to investigate the effect of different biomass conversion processes (microwave pyrolysis, carbon optimized gasification, and fast pyrolysis using electricity) on the composition and surface chemistry of biochar materials produced from corn stover (Zea mays L.), switchgrass (Panicum virgatum L.), and Ponderosa pine wood residue (Pinus ponderosa Lawson and C. Lawson) and determine the effect of biochars on mineralization of C, N, and S and associated soil enzymatic activities including esterase (fluorescein diacetate hydrolase, FDA), dehydrogenase (DHA), β-glucosidase (GLU), protease (PROT), and aryl sulfatase (ARSUL) in two different soils collected from footslope (Brookings) and crest (Maddock) positions of a landscape. Chemical properties of biochar materials produced from different batches of gasification process were fairly consistent. Biochar materials were found to be highly hydrophobic (low H/C values) with high aromaticity, irrespective of biomass feedstock and pyrolytic process. The short term incubation study showed that biochar had negative effects on microbial activity (FDA and DHA) and some enzymes including β-glucosidase and protease. Published by Elsevier B.V.

Waste-to-Energy Systems

DTIC Science & Technology

2009-04-01

at hospitals, at schools,” or wherever there are people creating masses of trash.5 Pyrolytic Gasification Pyrolytic gasification is not a new...prevalent with both. Gasification is . . . the chemical reaction and molecular breakdown or degradation of materials. The first pyrolytic gasification...dealing with about 2 tons of mixed solid waste per day, will destroy wood, paper card, food, plastics, and sanitary, clinical, and oil waste and

Fluidized bed gasification of industrial solid recovered fuels.

PubMed

Arena, Umberto; Di Gregorio, Fabrizio

2016-04-01

The study evaluates the technical feasibility of the fluidized bed gasification of three solid recovered fuels (SRFs), obtained as co-products of a recycling process. The SRFs were pelletized and fed to a pilot scale bubbling fluidized bed reactor, operated in gasification and co-gasification mode. The tests were carried out under conditions of thermal and chemical steady state, with a bed of olivine particles and at different values of equivalence ratio. The results provide a complete syngas characterization, in terms of its heating value and composition (including tars, particulates, and acid/basic pollutants) and of the chemical and physical characterization of bed material and entrained fines collected at the cyclone outlet. The feasibility of the fluidized bed gasification process of the different SRFs was evaluated with the support of a material and substance flow analysis, and a feedstock energy analysis. The results confirm the flexibility of fluidized bed reactor, which makes it one of the preferable technologies for the gasification of different kind of wastes, even in co-gasification mode. The fluidized bed gasification process of the tested SRFs appears technically feasible, yielding a syngas of valuable quality for energy applications in an appropriate plant configuration. Copyright © 2016 Elsevier Ltd. All rights reserved.

Raney nickel catalytic device

DOEpatents

O'Hare, Stephen A.

1978-01-01

A catalytic device for use in a conventional coal gasification process which includes a tubular substrate having secured to its inside surface by expansion a catalytic material. The catalytic device is made by inserting a tubular catalytic element, such as a tubular element of a nickel-aluminum alloy, into a tubular substrate and heat-treating the resulting composite to cause the tubular catalytic element to irreversibly expand against the inside surface of the substrate.

Hydrodynamic Stability of Multicomponent Droplet Gasification in Reduced Gravity

NASA Technical Reports Server (NTRS)

Aharon, I.; Shaw, B. D.

1995-01-01

This investigation addresses the problem of hydrodynamic stability of a two-component droplet undergoing spherically-symmetrical gasification. The droplet components are assumed to have characteristic liquid species diffusion times that are large relative to characteristic droplet surface regression times. The problem is formulated as a linear stability analysis, with a goal of predicting when spherically-symmetric droplet gasification can be expected to be hydrodynamically unstable from surface-tension gradients acting along the surface of a droplet which result from perturbations. It is found that for the conditions assumed in this paper (quasisteady gas phase, no initial droplet temperature gradients, diffusion-dominated gasification), surface tension gradients do not play a role in the stability characteristics. In addition, all perturbations are predicted to decay such that droplets were hydrodynamically stable. Conditions are identified, however, that deserve more analysis as they may lead to hydrodynamic instabilities driven by capillary effects.

Characterization of products obtained from pyrolysis and steam gasification of wood waste, RDF, and RPF.

PubMed

Hwang, In-Hee; Kobayashi, Jun; Kawamoto, Katsuya

2014-02-01

Pyrolysis and steam gasification of woody biomass chip (WBC) obtained from construction and demolition wastes, refuse-derived fuel (RDF), and refuse paper and plastic fuel (RPF) were performed at various temperatures using a lab-scale instrument. The gas, liquid, and solid products were examined to determine their generation amounts, properties, and the carbon balance between raw material and products. The amount of product gas and its hydrogen concentration showed a considerable difference depending on pyrolysis and steam gasification at higher temperature. The reaction of steam and solid product, char, contributed to an increase in gas amount and hydrogen concentration. The amount of liquid products generated greatly depended on temperature rather than pyrolysis or steam gasification. The compositions of liquid product varied relying on raw materials used at 500°C but the polycyclic aromatic hydrocarbons became the major compounds at 900°C irrespective of the raw materials used. Almost fixed carbon (FC) of raw materials remained as solid products under pyrolysis condition whereas FC started to decompose at 700°C under steam gasification condition. For WBC, both char utilization by pyrolysis at low temperature (500°C) and syngas recovery by steam gasification at higher temperature (900°C) might be practical options. From the results of carbon balance of RDF and RPF, it was confirmed that the carbon conversion to liquid products conspicuously increased as the amount of plastic increased in the raw material. To recover feedstock from RPF, pyrolysis for oil recovery at low temperature (500°C) might be one of viable options. Steam gasification at 900°C could be an option but the method of tar reforming (e.g. catalyst utilization) should be considered. Copyright © 2013 Elsevier Ltd. All rights reserved.

Updraft gasification of salmon processing waste

USDA-ARS?s Scientific Manuscript database

The purpose of this research is to judge the feasibility of gasification for the disposal of waste streams generated through salmon harvesting. Gasification is the process of converting carbonaceous materials into combustible “syngas” in a high temperature (above 700 °C), oxygen deficient environmen...

Continuous Removal of Coal-Gasification Residue

NASA Technical Reports Server (NTRS)

Collins, Earl R., Jr.; Suitor, J.; Dubis, D.

1986-01-01

Continuous-flow hopper processes solid residue from coal gasification, converting it from ashes, cinders, and clinkers to particles size of sand granules. Unit does not require repeated depressurization of lockhopper to admit and release materials. Therefore consumes less energy. Because unit has no airlock valves opened and closed repeatedly on hot, abrasive particles, subjected to lesser wear. Coal-gasification residue flows slowly through pressure-letdown device. Material enters and leaves continuously. Cleanout door on each pressure-letdown chamber allows access for maintenance and emergencies.

Sensing underground coal gasification by ground penetrating radar

NASA Astrophysics Data System (ADS)

Kotyrba, Andrzej; Stańczyk, Krzysztof

2017-12-01

The paper describes the results of research on the applicability of the ground penetrating radar (GPR) method for remote sensing and monitoring of the underground coal gasification (UCG) processes. The gasification of coal in a bed entails various technological problems and poses risks to the environment. Therefore, in parallel with research on coal gasification technologies, it is necessary to develop techniques for remote sensing of the process environment. One such technique may be the radar method, which allows imaging of regions of mass loss (voids, fissures) in coal during and after carrying out a gasification process in the bed. The paper describes two research experiments. The first one was carried out on a large-scale model constructed on the surface. It simulated a coal seam in natural geological conditions. A second experiment was performed in a shallow coal deposit maintained in a disused mine and kept accessible for research purposes. Tests performed in the laboratory and in situ conditions showed that the method provides valuable data for assessing and monitoring gasification surfaces in the UCG processes. The advantage of the GPR method is its high resolution and the possibility of determining the spatial shape of various zones and forms created in the coal by the gasification process.

Second stage gasifier in staged gasification and integrated process

DOEpatents

Liu, Guohai; Vimalchand, Pannalal; Peng, Wan Wang

2015-10-06

A second stage gasification unit in a staged gasification integrated process flow scheme and operating methods are disclosed to gasify a wide range of low reactivity fuels. The inclusion of second stage gasification unit operating at high temperatures closer to ash fusion temperatures in the bed provides sufficient flexibility in unit configurations, operating conditions and methods to achieve an overall carbon conversion of over 95% for low reactivity materials such as bituminous and anthracite coals, petroleum residues and coke. The second stage gasification unit includes a stationary fluidized bed gasifier operating with a sufficiently turbulent bed of predefined inert bed material with lean char carbon content. The second stage gasifier fluidized bed is operated at relatively high temperatures up to 1400.degree. C. Steam and oxidant mixture can be injected to further increase the freeboard region operating temperature in the range of approximately from 50 to 100.degree. C. above the bed temperature.

76 FR 5107 - Regulation of Oil-Bearing Hazardous Secondary Materials From the Petroleum Refining Industry...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-28

... Processed in a Gasification System To Produce Synthesis Gas; Tentative Determination To Deny Petition for... Synthesis Gas,'' published in the Federal Register on January 2, 2008. The EPA considered the petition... Refining Industry Processed in a Gasification System to Produce Synthesis Gas'' (Gasification Rule). This...

Comparison of phosphorus recovery from incineration and gasification sewage sludge ash.

PubMed

Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M; Thomsen, Tobias P; Ahrenfeldt, Jesper; Hauggaard-Nielsen, Henrik

2017-03-01

Incineration of sewage sludge is a common practice in many western countries. Gasification is an attractive option because of its high energy efficiency and flexibility in the usage of the produced gas. However, they both unavoidably produce sewage sludge ashes, a material that is rich in phosphorus, but which is commonly landfilled or used in construction materials. With current uncertainty in phosphate rock supply, phosphorus recovery from sewage sludge ashes has become interesting. In the present work, ashes from incineration and gasification of the same sewage sludge were compared in terms of phosphorus extractability using electrodialytic (ED) methods. The results show that comparable recovery rates of phosphorus were achieved with a single ED step for incineration ashes and a sequential combination of two ED steps for gasification ashes, which was due to a higher influence of iron and/or aluminium in phosphorus solubility for the latter. A product with lower level of metallic impurities and comparable to wet process phosphoric acid was eventually obtained from gasification ashes. Thus, gasification becomes an interesting alternative to incineration also in terms of phosphorus separation.

Waste-to-Energy and Fuel Cell Technologies Overview

DTIC Science & Technology

2011-01-13

Integration of stationary fuel cells with biomass gasification is a developing technology that is in need of demonstration. Innovation for Our...the PureCell®400 Innovation for Our Energy Future Gasification of wood wastes is another potential source of useful fuel gas. Wood waste... Gasification → Cleanup → Fuel Cell Gasification uses high temperature to convert cellulosic materials to fuel gas • Hydrogen (H2) • Carbon monoxide (CO

Gasification of yeast industry treatment plant sludge using downdraft Gasifier.

PubMed

Ayol, Azize; Tezer, Ozgun; Gurgen, Alim

2018-01-01

Sludges produced in biological wastewater treatment plants have rich organic materials in their characteristics. Recent research studies have focused on the energy recovery from sludge due to its high organic content. The gasification process is a thermal conversion technology transforming the chemical energy contained in a solid fuel into thermal energy and electricity. The produced syngas as a mixture of CO, CH 4 , H 2 and other gases can be used to generate electrical energy. The gasification of yeast industry sludge has been experimentally evaluated in a pilot scale downdraft-type gasifier as a route towards the energy recovery. The gasifier has 20 kg biomass/h fuel capacity. During gasification, the temperature achieved was more than 1,000°C in the gasifier, and then the syngas was transferred to the gas engine to yield the electricity. A load was connected to the grid box and approximately 1 kWh electrical power generation for 1 kg dry sludge was determined. The characteristics of residuals - ash, glassy material - were also analyzed. It was found that most of the heavy metals were fixed in the glassy material. Experimental results showed that the yeast industry sludge was an appropriate material for gasification studies and remarkable energy recovery was obtained in terms of power production by using syngas.

Gasification: A Cornerstone Technology

ScienceCinema

Gary Stiegel

2017-12-09

NETL is a leader in the science and technology of gasification - a process for the conversion of carbon-based materials such as coal into synthesis gas (syngas) that can be used to produce clean electrical energy, transportation fuels, and chemicals efficiently and cost-effectively using domestic fuel resources. Gasification is a cornerstone technology of 21st century zero emissions powerplants

Potential application of gasification to recycle food waste and rehabilitate acidic soil from secondary forests on degraded land in Southeast Asia.

PubMed

Yang, Zhanyu; Koh, Shun Kai; Ng, Wei Cheng; Lim, Reuben C J; Tan, Hugh T W; Tong, Yen Wah; Dai, Yanjun; Chong, Clive; Wang, Chi-Hwa

2016-05-01

Gasification is recognized as a green technology as it can harness energy from biomass in the form of syngas without causing severe environmental impacts, yet producing valuable solid residues that can be utilized in other applications. In this study, the feasibility of co-gasification of woody biomass and food waste in different proportions was investigated using a fixed-bed downdraft gasifier. Subsequently, the capability of biochar derived from gasification of woody biomass in the rehabilitation of soil from tropical secondary forests on degraded land (adinandra belukar) was also explored through a water spinach cultivation study using soil-biochar mixtures of different ratios. Gasification of a 60:40 wood waste-food waste mixture (w/w) produced syngas with the highest lower heating value (LHV) 5.29 MJ/m(3)-approximately 0.4-4.0% higher than gasification of 70:30 or 80:20 mixtures, or pure wood waste. Meanwhile, water spinach cultivated in a 2:1 soil-biochar mixture exhibited the best growth performance in terms of height (a 4-fold increment), weight (a 10-fold increment) and leaf surface area (a 5-fold increment) after 8 weeks of cultivation, owing to the high porosity, surface area, nutrient content and alkalinity of biochar. It is concluded that gasification may be an alternative technology to food waste disposal through co-gasification with woody biomass, and that gasification derived biochar is suitable for use as an amendment for the nutrient-poor, acidic soil of adinandra belukar. Copyright © 2016 Elsevier Ltd. All rights reserved.

Study on CO2 gasification reactivity and physical characteristics of biomass, petroleum coke and coal chars.

PubMed

Huo, Wei; Zhou, Zhijie; Chen, Xueli; Dai, Zhenghua; Yu, Guangsuo

2014-05-01

Gasification reactivities of six different carbonaceous material chars with CO2 were determined by a Thermogravimetric Analyzer (TGA). Gasification reactivities of biomass chars are higher than those of coke and coal chars. In addition, physical structures and chemical components of these chars were systematically tested. It is found that the crystalline structure is an important factor to evaluate gasification reactivities of different chars and the crystalline structures of biomass chars are less order than those of coke and coal chars. Moreover, initial gasification rates of these chars were measured at high temperatures and with relatively large particle sizes. The method of calculating the effectiveness factor η was used to quantify the effect of pore diffusion on gasification. The results show that differences in pore diffusion effects among gasification with various chars are prominent and can be attributed to different intrinsic gasification reactivities and physical characteristics of different chars. Copyright © 2014 Elsevier Ltd. All rights reserved.

Low temperature vapor phase digestion of graphite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, Robert A.

2017-04-18

A method for digestion and gasification of graphite for removal from an underlying surface is described. The method can be utilized to remove graphite remnants of a formation process from the formed metal piece in a cleaning process. The method can be particularly beneficial in cleaning castings formed with graphite molding materials. The method can utilize vaporous nitric acid (HNO.sub.3) or vaporous HNO.sub.3 with air/oxygen to digest the graphite at conditions that can avoid damage to the underlying surface.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bozkurt, Y.; Misirlioglu, Z.; Sinag, A.

The reactivities of chars obtained by pyrolysis of Bursa Mustafa Kemal Pasa Alpagut lignite and Balkesir Dursunbey Cakiirca lignite (Turkey) at different temperatures were determined by CO{sub 2} gasification and by combustion with O{sub 2}. Catalytic effect of Na{sub 2}CO{sub 3} on the CO{sub 2} and O{sub 2} gasification reactivity of chars was investigated. Gasification tests were performed in the fixed bed reactors operating at ambient pressure. Reactivity of chars during the CO{sub 2} gasification reactions was determined by calculating the reaction rate constants and reactivity of chars during the O{sub 2} gasification was determined by using ignition temperatures ofmore » the samples. Activation energies and Arrhenius constants of the chars on the CO{sub 2} gasification reactions were also calculated by the help of Arrhenius curves. The activation energy for CO{sub 2} gasification was generally decreased with pyrolysis temperature, due to the different surface characteristics and different nature of carbon atoms gasified as the gasification reactions proceed. Generally, the increase in pyrolysis temperature leads to an increase in gasification reactivity with CO{sub 2}. The reactivity of chars in catalytic gasification was higher than the corresponding non-catalytic reactivity of the same chars. Ignition temperature increased with increasing pyrolysis temperature.« less

Apparatus for fixed bed coal gasification

DOEpatents

Sadowski, Richard S.

1992-01-01

An apparatus for fixed-bed coal gasification is described in which coal such as caking coal is continuously pyrolyzed with clump formation inhibited, by combining the coal with a combustible gas and an oxidant, and then continually feeding the pyrolyzed coal under pressure and elevated temperature into the gasification region of a pressure vessel. The materials in the pressure vessel are allowed to react with the gasifying agents in order to allow the carbon contents of the pyrolyzed coal to be completely oxidized. The combustion of gas produced from the combination of coal pyrolysis and gasification involves combining a combustible gas coal and an oxidant in a pyrolysis chamber and heating the components to a temperature of at least 1600.degree. F. The products of coal pyrolysis are dispersed from the pyrolyzer directly into the high temperature gasification region of a pressure vessel. Steam and air needed for gasification are introduced in the pressure vessel and the materials exiting the pyrolyzer flow down through the pressure vessel by gravity with sufficient residence time to allow any carbon to form carbon monoxide. Gas produced from these reactions are then released from the pressure vessel and ash is disposed of.

First Experiences with the New Chalmers Gasifier

NASA Astrophysics Data System (ADS)

Thunman, H.; Seemann, M. C.

During summer 2007 a 2-6 MWth indirect gasification section was integrated into the loop of the existing 82➀2 MWth circulating fluidized bed boiler at Chalmers University. With help of a particle distributor the gasification unit is connected to the loop after the cyclone. Hot bed material entrained from the boiler is so transferred to the gasifier providing the heat for the production of a nearly nitrogen free product gas. Non-gasified char is returned together with the bed material into the boiler and converted. Biomass can be fed into both sections; the boiler and the gasifier. The gasification is separated from the boiler via two loop seals and a particle distributer, directing particles either back to the boiler or into the gasification section. For that reason the CFB boiler can be operated even after the retrofit independently, just like before, or in combined combustion/gasification mode. This possibility keeps the risk for a retrofit low. As, furthermore, the investment costs for the integration are considerably lower than standalone gasification units of that size, the retrofit is an easy way to extend the potential of a CFB Boiler towards bi- and tri-generation (heat, power, fuel) and enter new markets.

Simulation of biomass-steam gasification in fluidized bed reactors: Model setup, comparisons and preliminary predictions.

PubMed

Yan, Linbo; Lim, C Jim; Yue, Guangxi; He, Boshu; Grace, John R

2016-12-01

A user-defined solver integrating the solid-gas surface reactions and the multi-phase particle-in-cell (MP-PIC) approach is built based on the OpenFOAM software. The solver is tested against experiments. Then, biomass-steam gasification in a dual fluidized bed (DFB) gasifier is preliminarily predicted. It is found that the predictions agree well with the experimental results. The bed material circulation loop in the DFB can form automatically and the bed height is about 1m. The voidage gradually increases along the height of the bed zone in the bubbling fluidized bed (BFB) of the DFB. The U-bend and cyclone can separate the syngas in the BFB and the flue gas in the circulating fluidized bed. The concentration of the gasification products is relatively higher in the conical transition section, and the dry and nitrogen-free syngas at the BFB outlet is predicted to be composed of 55% H 2 , 20% CO, 20% CO 2 and 5% CH 4 . Copyright © 2016 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calo, J.M.; Suuberg, E.M.; Hradil, G.

This project is concerned with the study of the nature and behavior of ''active sites'' in char gasification. The research strategy involves use of model chars produced from the phenol-formaldehyde family of resins. These materials have been chosen since they have structural features similar to those in coals, but are much ''cleaner'' in that the concentration of potentially catalytic impurities can be maintained at low levels. It should be borne in mind that the objective of this work is to study non-catalytic gasification processes. In the previous quarterly report, we presented evidence that low temperature oxygen chemisorption does not providemore » a site-specific titration of active sites in chars; the uptake of oxygen by a cleaned char surface was unquestionably shown to be a function of temperature and oxygen partial pressure, and the importance of these variables differs from char to char. The fact that ''active surface area'' (ASA) determined by various arbitrary methods does seem to generally correlate with reactivity, seems to suggest that reactivities under various gasification and chemisorption conditions are correlated but that mechanisitic inferences cannot necessarily be drawn from such data. In the present report, we have extended the study of low temperature oxidation of chars, considering mass loss as well as oxygen uptake, since the two processes are essentially inseparable under a wide range of conditions. This work represents more than a simple attempt at trying to learn more about the oxygen chemisorption technique; rather it offers the opportunity to study the mechanism of oxygen attack on char under conditions that allow for better understanding of the fundamental processes. For these reasons, this work was performed in the pyrogasifier reactor (developed for CO/sub 2/ gasification reactivity studies), and complements the ongoing work in the TGA apparatus. 6 refs., 9 figs., 1 tab.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mihaela Grigore; Richard Sakurovs; David French

Gasification of coke contributes to its degradation in the blast furnace. In this study, the effect of gasification on the inherent catalytic minerals in cokes and their reciprocal influence on gasification are investigated. The catalytic mineral phases identified in the cokes used in this study were metallic iron, iron sulfides, and iron oxides. Metallic iron and pyrrhotite were rapidly oxidized during gasification to iron oxide. The catalysts had a strong influence on the apparent rates at the initial stages of reaction. As gasification proceeds, their effect on the reaction rate diminishes as a result of reducing the surface contact betweenmore » catalyst and carbon matrix because of carbon consumption around the catalyst particles; with extended burnout the reactivity of the coke becomes increasingly dependent on surface area. The reaction rate in the initial stages was also influenced by the particle size of the catalytic minerals; for a given catalytic iron level, the cokes whose catalytic minerals were more finely dispersed had a higher apparent reaction rate than cokes containing larger catalytic particles. Iron, sodium, and potassium in the amorphous phase did not appear to affect the reaction rate. 40 refs., 16 figs., 6 tabs.« less

Analysis of carbon-oxygen reactions by use of a square-input response technique and {sup 18}O isotope

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miura, Kouichi; Nakagawa, Hiroyuki

1996-12-31

Carbon gasification reaction has been investigated for decades including the pioneering works of Walker and his co-workers, but its mechanism has not been completely elucidated. The concept of the active surface area (ASA) was proposed by them, and its importance has been recognized. However, since ASA was measured by O{sub 2} chemisorption at below 300{degrees}C where carbon loss through gasification is negligible, it does not reflect the actual gasification situation. To overcome this weak point, measurements of ASA in a batch reactor and the so-called transient kinetic (TK) method were proposed. Ahmed and Back successfully measured the chemisorbed oxygen duringmore » the gasification using a batch reactor, and proposed a new mechanistic sequence for carbon-oxygen reaction which stresses the importance of the reaction between the gaseous oxygen and the chemisorbed oxygen. Radovic et al. proposed the concept of the reactive surface area (RSA), and reported excellent proportionality between the CO{sub 2} gasification rate and the RSA estimated by the TK and the TPD methods. Kapteijn et al. showed that the TK method with labeled molecules is more powerful to examine the mechanism. They found the presence of two types of surface oxygen complexes which desorb at different rates. A Square-input response (SIR) method is applied to the carbon-oxygen reaction. This method allows the observation of transient changes on two step changes. This method has been successfully applied to the analysis of a coal char gasification.« less

Performance, cost and environmental assessment of gasification-based electricity in India: A preliminary analysis

NASA Astrophysics Data System (ADS)

Rani, Abha; Singh, Udayan; Jayant; Singh, Ajay K.; Sankar Mahapatra, Siba

2017-07-01

Coal gasification processes are crucial to decarbonisation in the power sector. While underground coal gasification (UCG) and integrated gasification combined cycle (IGCC) are different in terms of the site of gasification, they have considerable similarities in terms of the types of gasifiers used. Of course, UCG offers some additional advantages such as reduction of the fugitive methane emissions accompanying the coal mining process. Nevertheless, simulation of IGCC plants involving surface coal gasification is likely to give reasonable indication of the 3E (efficiency, economics and emissions) prospects of the gasification pathway towards electricity. This paper will aim at Estimating 3E impacts (efficiency, environment, economics) of gasification processes using simulation carried out in the Integrated Environmental Control Model (IECM) software framework. Key plant level controls which will be studied in this paper will be based on Indian financial regulations and operating costs which are specific to the country. Also, impacts of CO2 capture and storage (CCS) in these plants will be studied. The various parameters that can be studied are plant load factor, impact of coal quality and price, type of CO2 capture process, capital costs etc. It is hoped that relevant insights into electricity generation from gasification may be obtained with this paper.

Potassium dichromate method of coal gasification the study of the typical organic compounds in water

NASA Astrophysics Data System (ADS)

Quan, Jiankang; Qu, Guangfei; Dong, Zhanneng; Lu, Pei; Cai, Yingying; Wang, Shibo

2017-05-01

The national standard method is adopted in this paper the water - digestion spectrophotometry for determination of the chemical oxygen demand (COD), after ultrasonic processing of coal gasification water for CODCr measurement. Using the control variable method, measured in different solution pH, ultrasonic frequency, ultrasonic power, reaction conditions of different initial solution concentration, the change of coal gasification water CODCr value under the action of ultrasonic, the experimental results shows that appear when measurement is allowed to fluctuate, data, in order to explain the phenomenon we adopt the combination of the high performance liquid chromatography and mass spectrometry before and after ultrasonic coal gasification qualitative analysis on composition of organic matter in water. To raw water sample chromatography - mass spectrometry (GC/MS) analysis, combined with the spectra analysis of each peak stands for material, select coal gasification typical organic substances in water, with the method of single digestion, the equivalent CODCr values measured after digestion. Order to produce, coal gasification water contained high concentration organic wastewater, such as the national standard method is adopted to eliminate the organic material, therefore to measure the CODCr value is lower than actual CODCr value of the emergence of the phenomenon, the experiment of the effect of ultrasound [9-13] is promote the complex organic chain rupture, also explains the actual measurement data fluctuation phenomenon in the experiment.

Optical spectra of coal gasification products in the RF plasmatron

NASA Astrophysics Data System (ADS)

Fedorovich, S. D.; Burakov, I. A.; Dudolin, A. A.; Markov, A. A.; Khtoo Naing, Aung; Ulziy, Batsamboo; Kavyrshin, D. I.

2017-11-01

The use of solid fuel gasification process is relevant to the regions where there is no opportunity to use natural gas as the main fuel. On the territory of the Russian Federation such regions are largely the Urals, Siberia and the Far East. In order to reduce the harmful effects on the environment solid fuel with high sulfur content, ash content and moisture are subjected to gasification process. One of the major problems of this process is to produce syngas with a low calorific value. For conventional types of gasification (gasification), the value of this quantity ranges 8 - 10 MJ / m3. The use of plasma gasification increases the calorific value of 12 - 16 MJ / m3 which allows the most efficient use of the syngas. The reason for the increase of the value lies in the change of temperature in the reaction zone. A significant rise in temperature in the reaction zone leads to an increase in methane formation reactions constant value, which allows to obtain a final product with a large calorific value. The HFI-plasma torch coal temperature reaches 3000 ° C, and the temperature of coal gasification products can reach 8000 ° C. The aim is to develop methods for determining the composition of the plasma gasification products obtained optical spectra. The Kuznetsky coal used as the starting material. Received and decrypted gasification products optical spectra in a wavelength range from 220 to 1000 nm. Recommendations for the use of the developed method for determining the composition of the plasma gasification products. An analysis of the advantages of using plasma gasification as compared with conventional gasification and coal combustion.

Effect of fuel origin on synergy during co-gasification of biomass and coal in CO2.

PubMed

Zhang, Yan; Zheng, Yan; Yang, Mingjun; Song, Yongchen

2016-01-01

The effect of fuel origin on synergy in coal/biomass blends during co-gasification has been assessed using a congruent-mass thermogravimetry analysis (TGA) method. Results revealed that synergy occurs when ash residuals are formed, followed by an almost complete gasification of biomass. Potassium species in biomass ash play a catalytic role in promoting gasification reactivity of coal char, which is a direct consequence of synergy during co-gasification. The SEM-EDS spectra provided conclusive evidence that the transfer of potassium from biomass to the surface of coal char occurs during co-pyrolysis/gasification. Biomass ash rich in silica eliminated synergy in coal/biomass blends but not to the extent of inhibiting the reaction rate of the blended chars to make it slower than that of separated ones. The best result in terms of synergy was concluded to be the combination of low-ash coal and K-rich biomass. Copyright © 2015 Elsevier Ltd. All rights reserved.

30 CFR 870.5 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... situ coal mining means activities conducted on the surface or underground in connection with in-place... not limited to, in situ gasification, in situ leaching, slurry mining, solution mining, bore hole mining, and fluid recovery mining. At this time, part 870 considers only in situ gasification. Inherent...

30 CFR 870.5 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... situ coal mining means activities conducted on the surface or underground in connection with in-place... not limited to, in situ gasification, in situ leaching, slurry mining, solution mining, bore hole mining, and fluid recovery mining. At this time, part 870 considers only in situ gasification. Inherent...

30 CFR 870.5 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... situ coal mining means activities conducted on the surface or underground in connection with in-place... not limited to, in situ gasification, in situ leaching, slurry mining, solution mining, bore hole mining, and fluid recovery mining. At this time, part 870 considers only in situ gasification. Inherent...

30 CFR 870.5 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... situ coal mining means activities conducted on the surface or underground in connection with in-place... not limited to, in situ gasification, in situ leaching, slurry mining, solution mining, bore hole mining, and fluid recovery mining. At this time, part 870 considers only in situ gasification. Inherent...

30 CFR 870.5 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... situ coal mining means activities conducted on the surface or underground in connection with in-place... not limited to, in situ gasification, in situ leaching, slurry mining, solution mining, bore hole mining, and fluid recovery mining. At this time, part 870 considers only in situ gasification. Inherent...

Pyrolysis of reinforced polymer composites: Parameterizing a model for multiple compositions

NASA Astrophysics Data System (ADS)

Martin, Geraldine E.

A single set of material properties was developed to describe the pyrolysis of fiberglass reinforced polyester composites at multiple composition ratios. Milligram-scale testing was performed on the unsaturated polyester (UP) resin using thermogravimetric analysis (TGA) coupled with differential scanning calorimetry (DSC) to establish and characterize an effective semi-global reaction mechanism, of three consecutive first-order reactions. Radiation-driven gasification experiments were conducted on UP resin and the fiberglass composites at compositions ranging from 41 to 54 wt% resin at external heat fluxes from 30 to 70 kW m -2. The back surface temperature was recorded with an infrared camera and used as the target for inverse analysis to determine the thermal conductivity of the systematically isolated constituent species. Manual iterations were performed in a comprehensive pyrolysis model, ThermaKin. The complete set of properties was validated for the ability to reproduce the mass loss rate during gasification testing.

Process for fixed bed coal gasification

DOEpatents

Sadowski, Richard S.

1992-01-01

The combustion of gas produced from the combination of coal pyrolysis and gasification involves combining a combustible gas coal and an oxidant in a pyrolysis chamber and heating the components to a temperature of at least 1600.degree. F. The products of coal pyrolysis are dispersed from the pyrolyzer directly into the high temperature gasification region of a pressure vessel. Steam and air needed for gasification are introduced in the pressure vessel and the materials exiting the pyrolyzer flow down through the pressure vessel by gravity with sufficient residence time to allow any carbon to form carbon monoxide. Gas produced from these reactions are then released from the pressure vessel and ash is disposed of.

Co-gasification of solid waste and lignite - a case study for Western Macedonia.

PubMed

Koukouzas, N; Katsiadakis, A; Karlopoulos, E; Kakaras, E

2008-01-01

Co-gasification of solid waste and coal is a very attractive and efficient way of generating power, but also an alternative way, apart from conventional technologies such as incineration and landfill, of treating waste materials. The technology of co-gasification can result in very clean power plants using a wide range of solid fuels but there are considerable economic and environmental challenges. The aim of this study is to present the available existing co-gasification techniques and projects for coal and solid wastes and to investigate the techno-economic feasibility, concerning the installation and operation of a 30MW(e) co-gasification power plant based on integrated gasification combined cycle (IGCC) technology, using lignite and refuse derived fuel (RDF), in the region of Western Macedonia prefecture (WMP), Greece. The gasification block was based on the British Gas-Lurgi (BGL) gasifier, while the gas clean-up block was based on cold gas purification. The competitive advantages of co-gasification systems can be defined both by the fuel feedstock and production flexibility but also by their environmentally sound operation. It also offers the benefit of commercial application of the process by-products, gasification slag and elemental sulphur. Co-gasification of coal and waste can be performed through parallel or direct gasification. Direct gasification constitutes a viable choice for installations with capacities of more than 350MW(e). Parallel gasification, without extensive treatment of produced gas, is recommended for gasifiers of small to medium size installed in regions where coal-fired power plants operate. The preliminary cost estimation indicated that the establishment of an IGCC RDF/lignite plant in the region of WMP is not profitable, due to high specific capital investment and in spite of the lower fuel supply cost. The technology of co-gasification is not mature enough and therefore high capital requirements are needed in order to set up a direct co-gasification plant. The cost of electricity estimated was not competitive, compared to the prices dominating the Greek electricity market and thus further economic evaluation is required. The project would be acceptable if modular construction of the unit was first adopted near operating power plants, based on parallel co-gasification, and gradually incorporating the remaining process steps (gas purification, power generation) with the aim of eventually establishing a true direct co-gasification plant.

Imperium/Lanzatech Syngas Fermentation Project - Biomass Gasification and Syngas Conditioning for Fermentation Evaluation: Cooperative Research and Development Final Report, CRADA Number CRD-12-474

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilcox, E.

2014-09-01

LanzaTech and NREL will investigate the integration between biomass gasification and LanzaTech's proprietary gas fermentation process to produce ethanol and 2,3-butanediol. Using three feed materials (woody biomass, agricultural residue and herbaceous grass) NREL will produce syngas via steam indirect gasification and syngas conditioning over a range of process relevant operating conditions. The gasification temperature, steam-to-biomass ratio of the biomass feed into the gasifier, and several levels of syngas conditioning (based on temperature) will be varied to produce multiple syngas streams that will be fed directly to 10 liter seed fermenters operating with the Lanzatech organism. The NREL gasification system willmore » then be integrated with LanzaTech's laboratory pilot unit to produce large-scale samples of ethanol and 2,3-butanediol for conversion to fuels and chemicals.« less

Gasification of black liquor

DOEpatents

Kohl, A.L.

1987-07-28

A concentrated aqueous black liquor containing carbonaceous material and alkali metal sulfur compounds is treated in a gasifier vessel containing a relatively shallow molten salt pool at its bottom to form a combustible gas and a sulfide-rich melt. The gasifier vessel, which is preferably pressurized, has a black liquor drying zone at its upper part, a black liquor solids gasification zone located below the drying zone, and a molten salt sulfur reduction zone which comprises the molten salt pool. A first portion of an oxygen-containing gas is introduced into the gas space in the gasification zone immediately above the molten salt pool. The remainder of the oxygen-containing gas is introduced into the molten salt pool in an amount sufficient to cause gasification of carbonaceous material entering the pool from the gasification zone but not sufficient to create oxidizing conditions in the pool. The total amount of the oxygen-containing gas introduced both above the pool and into the pool constitutes between 25 and 55% of the amount required for complete combustion of the black liquor feed. A combustible gas is withdrawn from an upper portion of the drying zone, and a melt in which the sulfur content is predominantly in the form of alkali metal sulfide is withdrawn from the molten salt sulfur reduction zone. 2 figs.

Gasification of black liquor

DOEpatents

Kohl, Arthur L.

1987-07-28

A concentrated aqueous black liquor containing carbonaceous material and alkali metal sulfur compounds is treated in a gasifier vessel containing a relatively shallow molten salt pool at its bottom to form a combustible gas and a sulfide-rich melt. The gasifier vessel, which is preferably pressurized, has a black liquor drying zone at its upper part, a black liquor solids gasification zone located below the drying zone, and a molten salt sulfur reduction zone which comprises the molten salt pool. A first portion of an oxygen-containing gas is introduced into the gas space in the gasification zone immediatley above the molten salt pool. The remainder of the oxygen-containing gas is introduced into the molten salt pool in an amount sufficient to cause gasification of carbonaceous material entering the pool from the gasification zone but not sufficient to create oxidizing conditions in the pool. The total amount of the oxygen-containing gas introduced both above the pool and into the pool constitutes between 25 and 55% of the amount required for complete combustion of the black liquor feed. A combustible gas is withdrawn from an upper portion of the drying zone, and a melt in which the sulfur content is predominantly in the form of alkali metal sulfide is withdrawn from the molten salt sulfur reduction zone.

Plasma gasification of municipal solid waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carter, G.W.; Tsangaris, A.V.

1995-12-31

Resorption Canada Limited (RCL) has conducted extensive operational testing with plasma technology in their plasma facility near Ottawa, Ontario, Canada to develop an environmentally friendly waste disposal process. Plasma technology, when utilized in a reactor vessel with the exclusion of oxygen, provides for the complete gasification of all combustibles in source materials with non-combustibles being converted to a non-hazardous slag. The energy and environmental characteristics of the plasma gasification of carbonaceous waste materials were studied over a period of eight years during which RCL completed extensive experimentation with MSW. A plasma processing system capable of processing 200--400 lbs/hr of MSWmore » was designed and built. The experimentation on MSW concentrated on establishing the optimum operating parameters and determining the energy and environmental characteristics at these operating parameters.« less

Characterization of coal gasification slag-based activated carbon and its potential application in lead removal.

PubMed

Xu, Yiting; Chai, Xiaoli

2018-02-01

Highly porous activated carbons were prepared from a coal gasification slag (CGS) precursor, by KOH activation to remove Pb 2+ from aqueous solution. The effects of pretreatment methods and activation parameters on the properties of the activated carbon were investigated, such as KOH/CGS mass ratio, activation temperature and activation time. The results showed that the maximum Brunauer-Emmett-Teller surface area and total pore volume with the value of 2481 m 2  g -1 and of 1.711 cc g -1 were obtained at a KOH/CGS ratio of 3.0 by physical mixing, an activation temperature of 750°C and an activation time of 80 min. SEM, FTIR and EA analyses indicated that pronounced pores existed on the exterior surface of the activated samples, and the contents of H and O decreased due to the loss of surface chemical groups during activation. Experimental data for the Pb 2+ adsorption were fitted well by Freundlich equation and a pseudo-second-order model with a maximum experimental adsorption capacity of 141 mg/g. All of the results indicated that CGS could be a promising material to prepare porous activated carbon for Pb 2+ removal from wastewater.

Hydrogen production from biomass gasification using biochar as a catalyst/support.

PubMed

Yao, Dingding; Hu, Qiang; Wang, Daqian; Yang, Haiping; Wu, Chunfei; Wang, Xianhua; Chen, Hanping

2016-09-01

Biochar is a promising catalyst/support for biomass gasification. Hydrogen production from biomass steam gasification with biochar or Ni-based biochar has been investigated using a two stage fixed bed reactor. Commercial activated carbon was also studied as a comparison. Catalyst was prepared with an impregnation method and characterized by X-ray diffraction, specific surface and porosity analysis, X-ray fluorescence and scanning electron micrograph. The effects of gasification temperature, steam to biomass ratio, Ni loading and bio-char properties on catalyst activity in terms of hydrogen production were explored. The Ni/AC catalyst showed the best performance at gasification temperature of 800°C, S/B=4, Ni loading of 15wt.%. Texture and composition characterization of the catalysts suggested the interaction between volatiles and biochar promoted the reforming of pyrolysis volatiles. Cotton-char supported Ni exhibited the highest activity of H2 production (64.02vol.%, 92.08mgg(-1) biomass) from biomass gasification, while rice-char showed the lowest H2 production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Physicochemical properties and gasification reactivity of the ultrafine semi-char derived from a bench-scale fluidized bed gasifier

NASA Astrophysics Data System (ADS)

Zhang, Yukui; Zhang, Haixia; Zhu, Zhiping; Na, Yongjie; Lu, Qinggang

2017-08-01

Zhundong coalfield is the largest intact coalfield worldwide and fluidized bed gasification has been considered as a promising way to achieve its clean and efficient utilization. The purpose of this study is to investigate the physicochemical properties and gasification reactivity of the ultrafine semi-char, derived from a bench-scale fluidized bed gasifier, using Zhundong coal as fuel. The results obtained are as follows. In comparison to the raw coal, the carbon and ash content of the semi-char increase after partial gasification, but the ash fusion temperatures of them show no significant difference. Particularly, 76.53% of the sodium in the feed coal has released to the gas phase after fluidized bed gasification. The chemical compositions of the semi-char are closely related to its particle size, attributable to the distinctly different natures of diverse elements. The semi-char exhibits a higher graphitization degree, higher BET surface area, and richer meso- and macropores, which results in superior gasification reactivity than the coal char. The chemical reactivity of the semi-char is significantly improved by an increased gasification temperature, which suggests the necessity of regasification of the semi-char at a higher temperature. Consequently, it will be considered feasible that these carbons in the semi-char from fluidized bed gasifiers are reclaimed and reused for the gasification process.

Changes imposed by pyrolysis, thermal gasification and incineration on composition and phosphorus fertilizer quality of municipal sewage sludge.

PubMed

Thomsen, Tobias Pape; Sárossy, Zsuzsa; Ahrenfeldt, Jesper; Henriksen, Ulrik B; Frandsen, Flemming J; Müller-Stöver, Dorette Sophie

2017-08-01

Fertilizer quality of ash and char from incineration, gasification and pyrolysis of a single municipal sewage sludge sample were investigated by comparing composition and phosphorus (P) plant availability. A process for post oxidation of gasification ash and pyrolysis char was developed and the oxidized materials were investigated as well. Sequential extraction with full elemental balances of the extracted pools as well as scanning electron microscopy with energy dispersive X-ray spectroscopy were used to investigate the mechanisms driving the observed differences in composition and P plant availability in a short-term soil incubation study. The compositional changes related mainly to differences in the proximate composition as well as to the release of especially nitrogen, sulfur, cadmium and to some extent, phosphorus (P). The cadmium load per unit of P was reduced with 75-85% in gasification processes and 10-15% in pyrolysis whereas no reduction was observed in incineration processes. The influence on other heavy metals was less pronounced. The plant availability of P in the substrates varied from almost zero to almost 100% of the plant availability of P in the untreated sludge. Post-oxidized slow pyrolysis char was found to be the substrate with the highest P fertilizer value while ash from commercial fluid bed sludge incineration had the lowest P fertilizer quality. The high P fertilizer value in the best substrate is suggested to be a function of several different mechanisms including structural surface changes and improvements in the association of P to especially magnesium, calcium and aluminum. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physico-chemical properties and gasification reactivity of co-pyrolysis char from different rank of coal blended with lignocellulosic biomass: Effects of the cellulose.

PubMed

Wu, Zhiqiang; Wang, Shuzhong; Luo, Zhengyuan; Chen, Lin; Meng, Haiyu; Zhao, Jun

2017-07-01

In this paper, the influence of cellulose on the physicochemical properties and the gasification reactivity of co-pyrolysis char was investigated. A specific surface area analyzer and an X-ray diffraction system were used to characterize the pore structure and the micro-crystalline structure of char. Fractal theory and deconvolution method were applied to quantitatively investigate the influence of cellulose on the structure of co-pyrolysis char. The results indicate that the improvements in the pore structure due to the presence of cellulose are more pronounced in the case of anthracite char with respect to bituminous char. Cellulose promotes the ordering of micro-scale structure and the uniformity of both anthracite and bituminous char, while the negative synergetic effect was observed during gasification of co-pyrolysis char. The exponential relationships between fractal dimension and specific surface area were determined, along with the relations between the gasification reactivity index and the microcrystalline structure parameter. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fluid bed gasification--plasma converter process generating energy from solid waste: experimental assessment of sulphur species.

PubMed

Morrin, Shane; Lettieri, Paola; Chapman, Chris; Taylor, Richard

2014-01-01

Often perceived as a Cinderella material, there is growing appreciation for solid waste as a renewable content thermal process feed. Nonetheless, research on solid waste gasification and sulphur mechanisms in particular is lacking. This paper presents results from two related experiments on a novel two stage gasification process, at demonstration scale, using a sulphur-enriched wood pellet feed. Notable SO2 and relatively low COS levels (before gas cleaning) were interesting features of the trials, and not normally expected under reducing gasification conditions. Analysis suggests that localised oxygen rich regions within the fluid bed played a role in SO2's generation. The response of COS to sulphur in the feed was quite prompt, whereas SO2 was more delayed. It is proposed that the bed material sequestered sulphur from the feed, later aiding SO2 generation. The more reducing gas phase regions above the bed would have facilitated COS--hence its faster response. These results provide a useful insight, with further analysis on a suite of performed experiments underway, along with thermodynamic modelling. Copyright © 2013 Elsevier Ltd. All rights reserved.

Optical Fiber Chemical Sensor with Sol-Gel Derived Refractive Material as Transducer for High Temperature Gas Sensing in Clean Coal Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shiquan Tao

2006-12-31

The chemistry of sol-gel derived silica and refractive metal oxide has been systematically studied. Sol-gel processes have been developed for preparing porous silica and semiconductor metal oxide materials. Micelle/reversed micelle techniques have been developed for preparing nanometer sized semiconductor metal oxides and noble metal particles. Techniques for doping metal ions, metal oxides and nanosized metal particles into porous sol-gel material have also been developed. Optical properties of sol-gel derived materials in ambient and high temperature gases have been studied by using fiber optic spectroscopic techniques, such as fiber optic ultraviolet/visible absorption spectrometry, fiber optic near infrared absorption spectrometry and fibermore » optic fluorescence spectrometry. Fiber optic spectrometric techniques have been developed for investigating the optical properties of these sol-gel derived materials prepared as porous optical fibers or as coatings on the surface of silica optical fibers. Optical and electron microscopic techniques have been used to observe the microstructure, such as pore size, pore shape, sensing agent distribution, of sol-gel derived material, as well as the size and morphology of nanometer metal particle doped in sol-gel derived porous silica, the nature of coating of sol-gel derived materials on silica optical fiber surface. In addition, the chemical reactions of metal ion, nanostructured semiconductor metal oxides and nanometer sized metal particles with gas components at room temperature and high temperatures have also been investigated with fiber optic spectrometric methods. Three classes of fiber optic sensors have been developed based on the thorough investigation of sol-gel chemistry and sol-gel derived materials. The first group of fiber optic sensors uses porous silica optical fibers doped with metal ions or metal oxide as transducers for sensing trace NH{sub 3} and H{sub 2}S in high temperature gas samples. The second group of fiber optic sensors uses sol-gel derived porous silica materials doped with nanometer particles of noble metals in the form of fiber or coating for sensing trace H{sub 2}, NH{sub 3} and HCl in gas samples at for applications ambient temperature. The third classes of fiber optic sensors use sol-gel derived semiconductor metal oxide coating on the surface of silica optical fiber as transducers for selectively sensing H{sub 2}, CH{sub 4} and CO at high temperature. In addition, optical fiber temperature sensors use the fluorescence signal of rare-earth metal ions doped porous silica optical fiber or the optical absorption signal of thermochromic metal oxide materials coated on the surface of silica optical fibers have also been developed for monitoring gas temperature of corrosive gas. Based on the results obtained from this project, the principle of fiber optic sensor techniques for monitoring matrix gas components as well as trace components of coal gasification derived syngas has been established. Prototype sensors for sensing trace ammonia and hydrogen sulfide in gasification derived syngas have been built up in our laboratory and have been tested using gas samples with matrix gas composition similar to that of gasification derived fuel gas. Test results illustrated the feasibility of these sensors for applications in IGCC processes.« less

Investigation of the efficiency of regenerative cooling of the ramjet combustor by gasification products of energy-intensive material

NASA Astrophysics Data System (ADS)

Averkov, I. S.; Arefyev, K. Yu.; Baykov, A. V.; Yanovskiy, L. S.

2017-01-01

The results of mathematical modeling of the thermal state of combustion chambers with regenerative cooling for ramjet engines of promising flying vehicles are presented. The cooling of combustion chambers by the gasification products of a combined charge of the energy-intensive material is considered, where the polyethylene is used as a stuff, and the HMX-based compounds are used as the active substance. The flow rates of the cooling eneregy-intensive material are determined, which provide acceptable levels of temperatures of combustion chambers at various modes of engines operation are determined.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vorres, K S

The overall accomplishments of the HYGAS program to date are that it has demonstrated the key process concepts and integrated unit operations of coal gasification. It has also demonstrated several methods of hydrogen generation, including catalytic steam reforming of natural gas, electrothermal gasification, and also steam-oxygen gasification. A total of 37 tests with lignite, including a total of 5500 tons of lignite processed, demonstrated the technical feasibility of a gasification process using lignite. A total of 17 tests with bituminous coal involved a total of 3100 tons. Some specific objectives of the HYGAS program for fiscal 1977 include tests tomore » be conducted with subbituminous coal. Data will be collected for use in the design of an effluent treatment and water reuse cycles in a commercial plant. New methanation catalysts will be tested. Materials testing will continue.« less

An Experimental Investigation of Sewage Sludge Gasification in a Fluidized Bed Reactor

PubMed Central

Calvo, L. F.; García, A. I.; Otero, M.

2013-01-01

The gasification of sewage sludge was carried out in a simple atmospheric fluidized bed gasifier. Flow and fuel feed rate were adjusted for experimentally obtaining an air mass : fuel mass ratio (A/F) of 0.2 < A/F < 0.4. Fuel characterization, mass and power balances, produced gas composition, gas phase alkali and ammonia, tar concentration, agglomeration tendencies, and gas efficiencies were assessed. Although accumulation of material inside the reactor was a main problem, this was avoided by removing and adding bed media along gasification. This allowed improving the process heat transfer and, therefore, gasification efficiency. The heating value of the produced gas was 8.4 MJ/Nm, attaining a hot gas efficiency of 70% and a cold gas efficiency of 57%. PMID:24453863

Comparative assessment of municipal sewage sludge incineration, gasification and pyrolysis for a sustainable sludge-to-energy management in Greece.

PubMed

Samolada, M C; Zabaniotou, A A

2014-02-01

For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current status of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a 'zero waste' solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated. Copyright © 2013 Elsevier Ltd. All rights reserved.

Simplifying pyrolysis; using gasification to produce corn stover and wheat straw biochar for sorptive and horitcultural media

USDA-ARS?s Scientific Manuscript database

Biochar is a renewable, useful material that can be utilized in many different applications. Biochar is commonly produced via pyrolysis methods using a retort-style oven with inert gas. Gasification is another method that can utilize pyrolysis to produce biochar, but with the advantage of not requir...

A Slag Management Toolset for Determining Optimal Coal Gasification Temperatures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwong, Kyei-Sing; Bennett, James P.

Abstract Gasifier operation is an intricate process because of the complex relationship between slag chemistry and temperature, limitations of feedstock materials, and operational preference. High gasification temperatures increase refractory degradation, while low gasification temperatures can lead to slag buildup on the gasifier sidewall or exit, either of which are problematic during operation. Maximizing refractory service life and gasifier performance require finding an optimized operating temperature range which is a function of the coal slag chemistry and viscosity. Gasifier operators typically use a slag’s viscosity-temperature relationship and/or ash-fusion fluid temperature to determine the gasification temperature range. NETL has built a slagmore » management toolset to determine the optimal temperature range for gasification of a carbon feedstock. This toolset is based on a viscosity database containing experimental data, and a number of models used to predict slag viscosity as a function of composition and temperature. Gasifier users typically have no scientific basis for selecting an operational temperature range for gasification, instead using experience to select operational conditions. The use of the toolset presented in this paper provides a basis for estimating or modifying carbon feedstock slags generated from ash impurities in carbon feedstock.« less

A Slag Management Toolset for Determining Optimal Coal Gasification Temperatures

DOE PAGES

Kwong, Kyei-Sing; Bennett, James P.

2016-11-25

Abstract Gasifier operation is an intricate process because of the complex relationship between slag chemistry and temperature, limitations of feedstock materials, and operational preference. High gasification temperatures increase refractory degradation, while low gasification temperatures can lead to slag buildup on the gasifier sidewall or exit, either of which are problematic during operation. Maximizing refractory service life and gasifier performance require finding an optimized operating temperature range which is a function of the coal slag chemistry and viscosity. Gasifier operators typically use a slag’s viscosity-temperature relationship and/or ash-fusion fluid temperature to determine the gasification temperature range. NETL has built a slagmore » management toolset to determine the optimal temperature range for gasification of a carbon feedstock. This toolset is based on a viscosity database containing experimental data, and a number of models used to predict slag viscosity as a function of composition and temperature. Gasifier users typically have no scientific basis for selecting an operational temperature range for gasification, instead using experience to select operational conditions. The use of the toolset presented in this paper provides a basis for estimating or modifying carbon feedstock slags generated from ash impurities in carbon feedstock.« less

Co-gasification of municipal solid waste and material recovery in a large-scale gasification and melting system.

PubMed

Tanigaki, Nobuhiro; Manako, Kazutaka; Osada, Morihiro

2012-04-01

This study evaluates the effects of co-gasification of municipal solid waste with and without the municipal solid waste bottom ash using two large-scale commercial operation plants. From the viewpoint of operation data, there is no significant difference between municipal solid waste treatment with and without the bottom ash. The carbon conversion ratios are as high as 91.7% and 95.3%, respectively and this leads to significantly low PCDD/DFs yields via complete syngas combustion. The gross power generation efficiencies are 18.9% with the bottom ash and 23.0% without municipal solid waste bottom ash, respectively. The effects of the equivalence ratio are also evaluated. With the equivalence ratio increasing, carbon monoxide concentration is decreased, and carbon dioxide and the syngas temperature (top gas temperature) are increased. The carbon conversion ratio is also increased. These tendencies are seen in both modes. Co-gasification using the gasification and melting system (Direct Melting System) has a possibility to recover materials effectively. More than 90% of chlorine is distributed in fly ash. Low-boiling-point heavy metals, such as lead and zinc, are distributed in fly ash at rates of 95.2% and 92.0%, respectively. Most of high-boiling-point heavy metals, such as iron and copper, are distributed in metal. It is also clarified that slag is stable and contains few harmful heavy metals such as lead. Compared with the conventional waste management framework, 85% of the final landfill amount reduction is achieved by co-gasification of municipal solid waste with bottom ash and incombustible residues. These results indicate that the combined production of slag with co-gasification of municipal solid waste with the bottom ash constitutes an ideal approach to environmental conservation and resource recycling. Copyright © 2011 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anastasia M. Gribik; Ronald E. Mizia; Harry Gatley

This project addresses both the technical and economic feasibility of replacing industrial gas in lime kilns with synthesis gas from the gasification of hog fuel. The technical assessment includes a materials evaluation, processing equipment needs, and suitability of the heat content of the synthesis gas as a replacement for industrial gas. The economic assessment includes estimations for capital, construction, operating, maintenance, and management costs for the reference plant. To perform these assessments, detailed models of the gasification and lime kiln processes were developed using Aspen Plus. The material and energy balance outputs from the Aspen Plus model were used asmore » inputs to both the material and economic evaluations.« less

Incineration and pyrolysis vs. steam gasification of electronic waste.

PubMed

Gurgul, Agnieszka; Szczepaniak, Włodzimierz; Zabłocka-Malicka, Monika

2018-05-15

Constructional complexity of items and their integration are the most distinctive features of electronic wastes. These wastes consist of mineral and polymeric materials and have high content of valuable metals that could be recovered. Elimination of polymeric components (especially epoxy resins) while leaving non-volatile mineral and metallic phases is the purpose of thermal treatment of electronic wastes. In the case of gasification, gaseous product of the process may be, after cleaning, used for energy recovery or chemical synthesis. If not melted, metals from solid products of thermal treatment of electronic waste could be recovered by hydrometallurgical processing. Three basic, high temperature ways of electronic waste processing, i.e. smelting/incineration, pyrolysis and steam gasification were shortly discussed in the paper, giving a special attention to gasification under steam, illustrated by laboratory experiments. Copyright © 2017 Elsevier B.V. All rights reserved.

Steam Pyrolysis of Polyimides: Effects of Steam on Raw Material Recovery.

PubMed

Kumagai, Shogo; Hosaka, Tomoyuki; Kameda, Tomohito; Yoshioka, Toshiaki

2015-11-17

Aromatic polyimides (PIs) have excellent thermal stability, which makes them difficult to recycle, and an effective way to recycle PIs has not yet been established. In this work, steam pyrolysis of the aromatic PI Kapton was performed to investigate the recovery of useful raw materials. Steam pyrolysis significantly enhanced the gasification of Kapton at 900 °C, resulting in 1963.1 mL g(-1) of a H2 and CO rich gas. Simultaneously, highly porous activated carbon with a high BET surface area was recovered. Steam pyrolysis increased the presence of polar functional groups on the carbon surface. Thus, it was concluded that steam pyrolysis shows great promise as a recycling technique for the recovery of useful synthetic gases and activated carbon from PIs without the need for catalysts and organic solvents.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The US Department of Energy is funding an underground coal gasification (UCG) project in steeply dipping coal beds (SDB), at North Knobs, about 8 miles west of Rawlins, Carbon County, Wyoming. The project is being conducted to determine the technical, economic and environmental viability of such a technology. The development of SDB is an interesting target for UCG since such beds contain coals not normally mineable economically by ordinary techniques. Although the underground gasification of SDB has not been attempted in the US, Soviet experience and theoretical work indicate that the gasification of SDB in place offers all the advantagesmore » of underground gasification of horizontal coal seams plus some unique characteristics. The steep angle of dip helps to channel the produced gases up dip to offtake holes and permits the ash and rubble to fall away from the reaction zone helping to mitigate the blocking of the reaction zone in swelling coals. The intersection of SDB with the surface makes the seam accessible for drilling and other preparation. The tests at the North Knobs site will consist of three tests, lasting 20, 80 and 80 days, respectively. A total of 9590 tons of coal is expected to be gasified, with surface facilities utilizing 15 acres of the total section of land. The environmental effects of the experiment are expected to be very small. The key environmental impact is potential groundwater contamination by reaction products from coal gasification. There is good evidence that the surrounding coal effectively blocks the migration of these contaminants.« less

Differences in gasification behaviors and related properties between entrained gasifier fly ash and coal char

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jing Gu; Shiyong Wu; Youqing Wu

2008-11-15

In the study, two fly ash samples from Texaco gasifiers were compared to coal char and the physical and chemical properties and reactivity of samples were investigated by scanning electron microscopy (SEM), SEM-energy-dispersive spectrometry (EDS), X-ray diffraction (XRD), N{sub 2} and CO{sub 2} adsorption method, and isothermal thermogravimetric analysis. The main results were obtained. The carbon content of gasified fly ashes exhibited 31-37%, which was less than the carbon content of 58-59% in the feed coal. The fly ashes exhibited higher Brunauer-Emmett-Teller (BET) surface area, richer meso- and micropores, more disordered carbon crystalline structure, and better CO{sub 2} gasification reactivitymore » than coal char. Ashes in fly ashes occurred to agglomerate into larger spherical grains, while those in coal char do not agglomerate. The minerals in fly ashes, especial alkali and alkaline-earth metals, had a catalytic effect on gasification reactivity of fly ash carbon. In the low-temperature range, the gasification process of fly ashes is mainly in chemical control, while in the high-temperature range, it is mainly in gas diffusion control, which was similar to coal char. In addition, the carbon in fly ashes was partially gasified and activated by water vapor and exhibited higher BET surface area and better gasification activity. Consequently, the fact that these carbons in fly ashes from entrained flow gasifiers are reclaimed and reused will be considered to be feasible. 15 refs., 7 figs., 5 tabs.« less

Gasification of torrefied Miscanthus × giganteus in an air-blown bubbling fluidized bed gasifier.

PubMed

Xue, G; Kwapinska, M; Horvat, A; Kwapinski, W; Rabou, L P L M; Dooley, S; Czajka, K M; Leahy, J J

2014-05-01

Torrefaction is suggested to be an effective method to improve the fuel properties of biomass and gasification of torrefied biomass should provide a higher quality product gas than that from unprocessed biomass. In this study, both raw and torrefied Miscanthus × giganteus (M×G) were gasified in an air-blown bubbling fluidized bed (BFB) gasifier using olivine as the bed material. The effects of equivalence ratio (ER) (0.18-0.32) and bed temperature (660-850°C) on the gasification performance were investigated. The results obtained suggest the optimum gasification conditions for the torrefied M × G are ER 0.21 and 800°C. The product gas from these process conditions had a higher heating value (HHV) of 6.70 MJ/m(3), gas yield 2m(3)/kg biomass (H2 8.6%, CO 16.4% and CH4 4.4%) and cold gas efficiency 62.7%. The comparison between raw and torrefied M × G indicates that the torrefied M × G is more suitable BFB gasification. Copyright © 2014 Elsevier Ltd. All rights reserved.

Environmental and economic performance of plasma gasification in Enhanced Landfill Mining.

PubMed

Danthurebandara, Maheshi; Van Passel, Steven; Vanderreydt, Ive; Van Acker, Karel

2015-11-01

This paper describes an environmental and economic assessment of plasma gasification, one of the viable candidates for the valorisation of refuse derived fuel from Enhanced Landfill Mining. The study is based on life cycle assessment and life cycle costing. Plasma gasification is benchmarked against conventional incineration, and the study indicates that the process could have significant impact on climate change, human toxicity, particulate matter formation, metal depletion and fossil depletion. Flue gas emission, oxygen usage and disposal of residues (plasmastone) are the major environmental burdens, while electricity production and metal recovery represent the major benefits. Reductions in burdens and improvements in benefits are found when the plasmastone is valorised in building materials instead of landfilling. The study indicates that the overall environmental performance of plasma gasification is better than incineration. The study confirms a trade-off between the environmental and economic performance of the discussed scenarios. Net electrical efficiency and investment cost of the plasma gasification process and the selling price of the products are the major economic drivers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hydrogen-Rich Syngas Production from Gasification and Pyrolysis of Solar Dried Sewage Sludge: Experimental and Modeling Investigations

PubMed Central

Ghrib, Amina; Friaa, Athar; Ouerghi, Aymen; Naoui, Slim; Belayouni, Habib

2017-01-01

Solar dried sewage sludge (SS) conversion by pyrolysis and gasification processes has been performed, separately, using two laboratory-scale reactors, a fixed-bed pyrolyzer and a downdraft gasifier, to produce mainly hydrogen-rich syngas. Prior to SS conversion, solar drying has been conducted in order to reduce moisture content (up to 10%). SS characterization reveals that these biosolids could be appropriate materials for gaseous products production. The released gases from SS pyrolysis and gasification present relatively high heating values (up to 9.96 MJ/kg for pyrolysis and 8.02  9.96 MJ/kg for gasification) due to their high contents of H2 (up to 11 and 7 wt%, resp.) and CH4 (up to 17 and 5 wt%, resp.). The yields of combustible gases (H2 and CH4) show further increase with pyrolysis. Stoichiometric models of both pyrolysis and gasification reactions were determined based on the global biomass formula, CαHβOγNδSε, in order to assist in the products yields optimization. PMID:28856162

Waste gasification vs. conventional Waste-to-Energy: a comparative evaluation of two commercial technologies.

PubMed

Consonni, Stefano; Viganò, Federico

2012-04-01

A number of waste gasification technologies are currently proposed as an alternative to conventional Waste-to-Energy (WtE) plants. Assessing their potential is made difficult by the scarce operating experience and the fragmentary data available. After defining a conceptual framework to classify and assess waste gasification technologies, this paper compares two of the proposed technologies with conventional WtE plants. Performances are evaluated by proprietary software developed at Politecnico di Milano and compared on the basis of a coherent set of assumptions. Since the two gasification technologies are configured as "two-step oxidation" processes, their energy performances are very similar to those of conventional plants. The potential benefits that may justify their adoption relate to material recovery and operation/emission control: recovery of metals in non-oxidized form; collection of ashes in inert, vitrified form; combustion control; lower generation of some pollutants. Copyright © 2012 Elsevier Ltd. All rights reserved.

Novel Attrition-Resistant Fischer Tropsch Catalyst

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weast, Logan, E.; Staats, William, R.

2009-05-01

There is a strong national interest in the Fischer-Tropsch synthesis process because it offers the possibility of making liquid hydrocarbon fuels from reformed natural gas or coal and biomass gasification products. This project explored a new approach that had been developed to produce active, attrition-resistant Fischer-Tropsch catalysts that are based on glass-ceramic materials and technology. This novel approach represented a promising solution to the problem of reducing or eliminating catalyst attrition and maximizing catalytic activity, thus reducing costs. The technical objective of the Phase I work was to demonstrate that glass-ceramic based catalytic materials for Fischer-Tropsch synthesis have resistance tomore » catalytic deactivation and reduction of particle size superior to traditional supported Fischer-Tropsch catalyst materials. Additionally, these novel glass-ceramic-based materials were expected to exhibit catalytic activity similar to the traditional materials. If successfully developed, the attrition-resistant Fischer-Tropsch catalyst materials would be expected to result in significant technical, economic, and social benefits for both producers and public consumers of Fischer-Tropsch products such as liquid fuels from coal or biomass gasification. This program demonstrated the anticipated high attrition resistance of the glass-ceramic materials. However, the observed catalytic activity of the materials was not sufficient to justify further development at this time. Additional testing documented that a lack of pore volume in the glass-ceramic materials limited the amount of surface area available for catalysis and consequently limited catalytic activity. However, previous work on glass-ceramic catalysts to promote other reactions demonstrated that commercial levels of activity can be achieved, at least for those reactions. Therefore, we recommend that glass-ceramic materials be considered again as potential Fischer-Tropsch catalysts if it can be demonstrated that materials with adequate pore volume can be produced. During the attrition resistance tests, it was learned that the glass-ceramic materials are very abrasive. Attention should be paid in any further developmental efforts to the potential for these hard, abrasive materials to damage reactors.« less

Gasification of torrefied fuel at power generation for decentralized consumers

NASA Astrophysics Data System (ADS)

Safin, R. R.; Khakimzyanov, I. F.; Galyavetdinov, N. R.; Mukhametzyanov, S. R.

2017-10-01

The increasing need of satisfaction of the existing needs of the population and the industry for electric energy, especially in the areas remote from the centralized energy supply, results in need of development of “small-scale energy generation”. At the same time, the basis in these regions is made by the energy stations, using imported fuel, which involve a problem of increase in cost and transportation of fuel to the place of consumption. The solution of this task is the use of the torrefied waste of woodworking and agricultural industry as fuel. The influence of temperature of torrefaction of wood fuel on the developed electric generator power is considered in the article. As a result of the experiments, it is revealed that at gasification of torrefied fuel from vegetable raw material, the generating gas with the increased content of hydrogen and carbon oxide, in comparison with gasification of the raw materials, is produced. Owing to this, the engine capacity increases that exerts direct impact on power generation by the electric generator.

Low temperature circulating fluidized bed gasification and co-gasification of municipal sewage sludge. Part 1: Process performance and gas product characterization.

PubMed

Thomsen, Tobias Pape; Sárossy, Zsuzsa; Gøbel, Benny; Stoholm, Peder; Ahrenfeldt, Jesper; Frandsen, Flemming Jappe; Henriksen, Ulrik Birk

2017-08-01

Results from five experimental campaigns with Low Temperature Circulating Fluidized Bed (LT-CFB) gasification of straw and/or municipal sewage sludge (MSS) from three different Danish municipal waste water treatment plants in pilot and demonstration scale are analyzed and compared. The gasification process is characterized with respect to process stability, process performance and gas product characteristics. All experimental campaigns were conducted at maximum temperatures below 750°C, with air equivalence ratios around 0.12 and with pure silica sand as start-up bed material. A total of 8600kg of MSS dry matter was gasified during 133h of operation. The average thermal loads during the five experiments were 62-100% of nominal capacity. The short term stability of all campaigns was excellent, but gasification of dry MSS lead to substantial accumulation of coarse and rigid, but un-sintered, ash particles in the system. Co-gasification of MSS with sufficient amounts of cereal straw was found to be an effective way to mitigate these issues as well as eliminate thermal MSS drying requirements. Characterization of gas products and process performance showed that even though gas composition varied substantially, hot gas efficiencies of around 90% could be achieved for all MSS fuel types. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bio-syngas production from agro-industrial biomass residues by steam gasification.

PubMed

Pacioni, Tatiana Ramos; Soares, Diniara; Domenico, Michele Di; Rosa, Maria Fernanda; Moreira, Regina de Fátima Peralta Muniz; José, Humberto Jorge

2016-12-01

This study evaluated the steam gasification potential of three residues from Brazilian agro-industry by assessing their reaction kinetics and syngas production at temperatures from 650 to 850°C and a steam partial pressure range of 0.05 to 0.3bar. The transition temperature between kinetic control and diffusion control regimes was identified. Prior to the gasification tests, the raw biomasses, namely apple pomace, spent coffee grounds and sawdust, were pyrolyzed in a fixed-bed quartz tubular reactor under controlled conditions. Gasification tests were performed isothermally in a magnetic suspension thermobalance and the reaction products were analyzed by a gas chromatograph with TCD/FID detectors. According to the characterization results, the samples presented higher carbon and lower volatile matter contents than the biomasses. Nevertheless, all of the materials had high calorific value. Syngas production was influenced by both temperature and steam partial pressure. Higher concentrations of H 2 and CO were found in the conversion range of 50-80% and higher concentrations of CO 2 in conversions around 10%, for all the gasified biochars. The H 2 /CO decreased with increasing temperature, mainly in kinetic control regime, in the lower temperature range. The results indicate the gasification potential of Brazilian biomass residues and are an initial and important step in the development of gasification processes in Brazil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Updraft gasification of salmon processing waste.

PubMed

Rowland, Sarah; Bower, Cynthia K; Patil, Krushna N; DeWitt, Christina A Mireles

2009-10-01

The purpose of this study was to judge the feasibility of gasification for the disposal of waste streams generated through salmon harvesting. Gasification is the process of converting carbonaceous materials into combustible "syngas" in a high temperature (above 700 degrees C), oxygen deficient environment. Syngas can be combusted to generate power, which recycles energy from waste products. At 66% to 79% moisture, raw salmon waste streams are too wet to undergo pyrolysis and combustion. Ground raw or de-oiled salmon whole fish, heads, viscera, or frames were therefore "dried" by mixing with wood pellets to a final moisture content of 20%. Ground whole salmon with moisture reduced to 12% moisture was gasified without a drying agent. Gasification tests were performed in a small-scale, fixed-bed, updraft gasifer. After an initial start-up period, the gasifier was loaded with 1.5 kg of biomass. Temperature was recorded at 6 points in the gasifier. Syngas was collected during the short steady-state period during each gasifier run and analyzed. Percentages of each type of gas in the syngas were used to calculate syngas heating value. High heating value (HHV) ranged from 1.45 to 1.98 MJ/kg. Bomb calorimetry determined maximum heating value for the salmon by-products. Comparing heating values shows the efficiency of gasification. Cold gas efficiencies of 13.6% to 26% were obtained from the various samples gasified. Though research of gasification as a means of salmon waste disposal and energy production is ongoing, it can be concluded that pre-dried salmon or relatively low moisture content mixtures of waste with wood are gasifiable.

Down-flow moving-bed gasifier with catalyst recycle

DOEpatents

Halow, John S.

1999-01-01

The gasification of coal and other carbonaceous materials by an endothermic gasification reaction is achieved in the presence of a catalyst in a down-flow, moving-bed gasifier. Catalyst is removed along with ash from the gasifier and is then sufficiently heated in a riser/burner by the combustion of residual carbon in the ash to volatilize the catalyst. This volatilized catalyst is returned to the gasifier where it uniformly contacts and condenses on the carbonaceous material. Also, the hot gaseous combustion products resulting from the combustion of the carbon in the ash along with excess air are introduced into the gasifier for providing heat energy used in the endothermic reaction.

Comparative assessment of municipal sewage sludge incineration, gasification and pyrolysis for a sustainable sludge-to-energy management in Greece

DOE Office of Scientific and Technical Information (OSTI.GOV)

Samolada, M.C.; Zabaniotou, A.A., E-mail: azampani@auth.gr

2014-02-15

Highlights: • The high output of MSS highlights the need for alternative routes of valorization. • Evaluation of 3 sludge-to-energy valorisation methods through SWOT analysis. • Pyrolysis is an energy and material recovery process resulting to ‘zero waste’. • Identification of challenges and barriers for MSS pyrolysis in Greece was investigated. • Adopters of pyrolysis systems face the challenge of finding new product markets. - Abstract: For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current statusmore » of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a ‘zero waste’ solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated.« less

Low-temperature catalytic gasification of food processing wastes. 1995 topical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elliott, D.C.; Hart, T.R.

The catalytic gasification system described in this report has undergone continuing development and refining work at Pacific Northwest National Laboratory (PNNL) for over 16 years. The original experiments, performed for the Gas Research Institute, were aimed at developing kinetics information for steam gasification of biomass in the presence of catalysts. From the fundamental research evolved the concept of a pressurized, catalytic gasification system for converting wet biomass feedstocks to fuel gas. Extensive batch reactor testing and limited continuous stirred-tank reactor tests provided useful design information for evaluating the preliminary economics of the process. This report is a follow-on to previousmore » interim reports which reviewed the results of the studies conducted with batch and continuous-feed reactor systems from 1989 to 1994, including much work with food processing wastes. The discussion here provides details of experiments on food processing waste feedstock materials, exclusively, that were conducted in batch and continuous- flow reactors.« less

Performance of biofuel processes utilising separate lignin and carbohydrate processing.

PubMed

Melin, Kristian; Kohl, Thomas; Koskinen, Jukka; Hurme, Markku

2015-09-01

Novel biofuel pathways with increased product yields are evaluated against conventional lignocellulosic biofuel production processes: methanol or methane production via gasification and ethanol production via steam-explosion pre-treatment. The novel processes studied are ethanol production combined with methanol production by gasification, hydrocarbon fuel production with additional hydrogen produced from lignin residue gasification, methanol or methane synthesis using synthesis gas from lignin residue gasification and additional hydrogen obtained by aqueous phase reforming in synthesis gas production. The material and energy balances of the processes were calculated by Aspen flow sheet models and add on excel calculations applicable at the conceptual design stage to evaluate the pre-feasibility of the alternatives. The processes were compared using the following criteria: energy efficiency from biomass to products, primary energy efficiency, GHG reduction potential and economy (expressed as net present value: NPV). Several novel biorefinery concepts gave higher energy yields, GHG reduction potential and NPV. Copyright © 2015 Elsevier Ltd. All rights reserved.

Analytic Hierarchy and Economic Analysis of a Plasma Gasification System for Naval Air Station Oceana-Dam Neck

DTIC Science & Technology

2014-08-30

asbestos containing material, pathological wastes, contaminated soils, glass waste, hazardous fly ash, solvents, ceramic waste, incinerator ash, paints...industrial waste into synthetic gas (Syn-Gas) and slag . For this study, the focus will be on the disposal of municipal solid waste. However, there is...Chemical Reactor The two primary by-products resulting from the gasification process are molten slag , which is collected through a portal at the base

In situ formation of coal gasification catalysts from low cost alkali metal salts

DOEpatents

Wood, Bernard J.; Brittain, Robert D.; Sancier, Kenneth M.

1985-01-01

A carbonaceous material, such as crushed coal, is admixed or impregnated with an inexpensive alkali metal compound, such as sodium chloride, and then pretreated with a stream containing steam at a temperature of 350.degree. to 650.degree. C. to enhance the catalytic activity of the mixture in a subsequent gasification of the mixture. The treatment may result in the transformation of the alkali metal compound into another, more catalytically active, form.

Experimental study on temperature profile of fixed - bed gasification of oil-palm fronds

NASA Astrophysics Data System (ADS)

Atnaw, Samson M.; Sulaiman, Shaharin A.; Moni, M. Nazmi Z.

2012-06-01

Currently the world's second largest palm oil producer Malaysia produces large amount of oil palm biomass each year. The abundance of the biomass introduces a challenge to utilize them as main feedstock for heat and energy generation. Although some oil palm parts and derivatives like empty fruit bunch and fibre have been commercialized as fuel, less attention has been given to oil palm fronds (OPF). Initial feasibility and characterization studies of OPF showed that it is highly feasible as fuel for gasification to produce high value gaseous fuel or syngas. This paper discusses the experimental gasification attempt carried out on OPF using a 50 kW lab scale downdraft gasifier and its results. The conducted study focused on the temperature distributions within the reactor and the characteristics of the dynamic temperature profile for each temperature zones during operation. OPF feedstock of one cubic inch in individual size with 15% average moisture content was utilized. An average pyrolysis zone temperature of 324°Cand an average oxidation zone temperature of 796°Cwere obtained over a total gasification period of 74 minutes. A maximum oxidation zone temperature of 952°Cwas obtained at 486 lpm inlet air flow rate and 10 kg/hr feedstock consumption rate. Stable bluish flare was produced for more than 70% of the total gasification time. The recorded temperature profiles produced closely similar patterns with the temperature profiles recorded from the gasification of woody materials. Similar temperature profile was obtained comparing the results from OPF gasification with that of woody biomass. Furthermore, the successful ignition of the syngas produced from OPF gasification ascertained that OPF indeed has a higher potential as gasification feedstock. Hence, more detailed studies need to be done for better understanding in exploiting the biomass as a high prospect alternative energy solution. In addition, a study of the effect of initial moisture content of OPF feedstock on the temperature distribution profile along the gasifier bed showed that initial moisture content of feedstock in the range of 15% gives satisfactory result, while experiment with feedstock having higher moisture content resulted in lower zone temperature values.

Down-flow moving-bed gasifier with catalyst recycle

DOEpatents

Halow, J.S.

1999-04-20

The gasification of coal and other carbonaceous materials by an endothermic gasification reaction is achieved in the presence of a catalyst in a down-flow, moving-bed gasifier. Catalyst is removed along with ash from the gasifier and is then sufficiently heated in a riser/burner by the combustion of residual carbon in the ash to volatilize the catalyst. This volatilized catalyst is returned to the gasifier where it uniformly contacts and condenses on the carbonaceous material. Also, the hot gaseous combustion products resulting from the combustion of the carbon in the ash along with excess air are introduced into the gasifier for providing heat energy used in the endothermic reaction. 1 fig.

Thermochemical characterization of pigeon pea stalk for its efficient utilization as an energy source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katyal, S.K.; Iyer, P.V.R.

2000-05-01

Pigeon pea stalk is a widely available biomass species in India. In this article the potential use of pigeon pea stalk as a fuel source through thermochemical conversion methods such as combustion, gasification, and pyrolysis has been investigated through experimentation using a thermogravimetric analyzer and pilot-plant-scale equipment. It has been proposed that pigeon pea stalks can be effectively utilized in two ways. The first is to pyrolyze the material to produce value-added products such as char, tar, and fuel gas. The second alternative is to partially pyrolyze the material to remove tar-forming volatiles, followed by gasification of reactive char tomore » generate producer gas.« less

Investigation of air gasification of micronized coal, mechanically activated using the plasma control of the process

NASA Astrophysics Data System (ADS)

Butakov, Evgenii; Burdukov, Anatoly; Chernetskiy, Mikhail; Kuznetsov, Victor

2017-10-01

Combination of the processes of coal combustion and gasification into a single technology of mechano-chemical and plasma-chemical activation is of a considerable scientific and technological interest. Enhancement of coal reactivity at their grinding with mechanical activation is associated with an increase in the reaction rate of carbon material, and at plasma-chemical effect, the main is an increase in reactivity of the oxidizing agent caused by the high plasma temperatures of atomic oxygen. The process of gasification was studied on the 1-MW setup with tangential scroll supply of pulverized coal-air mixture and cylindrical reaction chamber. Coal ground by the standard boiler mill is fed to the disintegrator, then, it is sent to the scroll inlet of the burner-reactor with the transport air. Pulverized coal is ignited by the plasmatron of 10-kW power. In experiments on air gasification of micronized coal, carried out at the temperature in the reaction chamber of 1000-1200°C and air excess α = 0.3-1, the data on CO concentration of 11% and H2 concentration of up to 6% were obtained. Air and air-steam gasification of mechanically-activated micronized coals with plasma control was calculated using SigmaFlow software package.

Feasibility Study of Coal Gasification/Fuel Cell/Cogeneration Project. Fort Hood, Texas Site. Project Description,

DTIC Science & Technology

1985-07-01

and Operation 132 6.7.5 Safety 135 6.7.6 System Control Description 136 6.7.6.1 Coal Gasification 136 6.7.6.2 Gas Cooling, Cleaning and Compression...the hydrogen content. The gas is then desulfurized and heated before final polishing and feeding to the fuel cell. Receiving compressed fuel gas and...4 CO Shift 1 Stretford Desulfurizer 3 Gas Compressors 3 Material Handling(3) 3 Subtotal 39 Scheduled Shutdown 14 Total Annual Shutdown 53

Updraft gasification of poultry litter at farm-scale--A case study.

PubMed

Taupe, N C; Lynch, D; Wnetrzak, R; Kwapinska, M; Kwapinski, W; Leahy, J J

2016-04-01

Farm and animal wastes are increasingly being investigated for thermochemical conversion, such as gasification, due to the urgent necessity of finding new waste treatment options. We report on an investigation of the use of a farm-scale, auto-thermal gasification system for the production of a heating gas using poultry litter (PL) as a feedstock. The gasification process was robust and reliable. The PL's ash melting temperature was 639°C, therefore the reactor temperature was kept around this value. As a result of the low reactor temperature the process performance parameters were low, with a cold gas efficiency (CGE) of 0.26 and a carbon conversion efficiency (CCE) of 0.44. The calorific value of the clean product gas was 3.39 MJ m(-3)N (LHV). The tar was collected as an emulsion containing 87 wt.% water and the extracted organic compounds were identified. The residual char exceeds thresholds for Zn and Cu to obtain European biochar certification; however, has potential to be classified as a pyrogenic carbonaceous material (PCM), which resembles a high nutrient biochar. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mission analysis for the federal fuels from biomass program. Volume IV. Termochemical conversion of biomass to fuels and chemicals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kohan, S.M.; Barkhordar, P.M.

1979-01-01

The thermochemical conversion of biomass feedstocks generally denotes technologies that use elevated temperatures to convert the fixed carbon content of biomass materials to produce other, more useful energy forms. Examples are combustion to produce heat, steam, electricity, or combinations of these; pyrolysis to produce gas (low- or intermediate-Btu), pyrolytic liquids and chemicals, and char; gasification to produce low or intermediate Btu gas (and, from IBG, additional products such as SNG, ammonia, methanol, or Fischer-Tropsch liquids); and liquefaction to produce heavy fuel oil or, with upgrading, lighter-boiling liquid products such as distillates, light fuel oils, or gasoline. This section discusses themore » selection of the feedstock used in the analysis of thermochemical conversion technologies. The following sections present detailed technical and economic evaluations of biomass conversion to electricity and steam by combustion, SNG by gasification and methanation, methanol by gasification and synthesis, oil by catalytic liquefaction, oil and char by pyrolysis, and ammonia by gasification and synthesis. The conversion options were reviewed with DOE for approval at the start of the project.« less

Groundnut shell gasification performance in a fluidized bed gasifier with bubbling air as gasification medium.

PubMed

Singh, Dharminder; Yadav, Sanjeev; Rajesh, V M; Mohanty, Pravakar

2018-05-24

This work was focused on finding the groundnut shell (GNS) gasification performance in a fluidized bed gasifier with bubbling air as gasification medium. GNS in powder form (a mixture of different particle size as given in table 8 in the article) was gasified using naturally available river sand as bed material, top of the bed feeding, conventional charcoal as bed heating medium, and two cyclones for proper cleaning and cooling the product gas. Experiments were performed using different operating conditions such as equivalence ratio (ER) between 0.29 and 0.33, bed temperature between 650°C and 800°C, and feedstock feeding rate between 36 and 31.7 kg/h. Different parameters were evaluated to study the gasifier performance such as gas yield, cold gas efficiency, carbon conversion efficiency (CCE), and high heating value. The most suitable ER value was found to be 0.31, giving the most stable bed temperature profile at 714.4°C with 5-10% fluctuation. Cold gas efficiency and CCE at optimal ER of 0.31 was found to be 71.8% and 91%, respectively.

Unmixed fuel processors and methods for using the same

DOEpatents

Kulkarni, Parag Prakash; Cui, Zhe

2010-08-24

Disclosed herein are unmixed fuel processors and methods for using the same. In one embodiment, an unmixed fuel processor comprises: an oxidation reactor comprising an oxidation portion and a gasifier, a CO.sub.2 acceptor reactor, and a regeneration reactor. The oxidation portion comprises an air inlet, effluent outlet, and an oxygen transfer material. The gasifier comprises a solid hydrocarbon fuel inlet, a solids outlet, and a syngas outlet. The CO.sub.2 acceptor reactor comprises a water inlet, a hydrogen outlet, and a CO.sub.2 sorbent, and is configured to receive syngas from the gasifier. The regeneration reactor comprises a water inlet and a CO.sub.2 stream outlet. The regeneration reactor is configured to receive spent CO.sub.2 adsorption material from the gasification reactor and to return regenerated CO.sub.2 adsorption material to the gasification reactor, and configured to receive oxidized oxygen transfer material from the oxidation reactor and to return reduced oxygen transfer material to the oxidation reactor.

Investigation of the crater-like microdefects induced by laser shock processing with aluminum foil as absorbent layer

NASA Astrophysics Data System (ADS)

Ye, Y. X.; Xuan, T.; Lian, Z. C.; Feng, Y. Y.; Hua, X. J.

2015-06-01

This paper reports that 3D crater-like microdefects form on the metal surface when laser shock processing (LSP) is applied. LSP was conducted on pure copper block using the aluminum foil as the absorbent material and water as the confining layer. There existed the bonding material to attach the aluminum foil on the metal target closely. The surface morphologies and metallographs of copper surfaces were characterized with 3D profiler, the optical microscopy (OM) or the scanning electron microscopy (SEM). Temperature increases of metal surface due to LSP were evaluated theoretically. It was found that, when aluminum foil was used as the absorbent material, and if there existed air bubbles in the bonding material, the air temperatures within the bubbles rose rapidly because of the adiabatic compression. So at the locations of the air bubbles, the metal materials melted and micromelting pool formed. Then under the subsequent expanding of the air bubbles, a secondary shock wave was launched against the micromelting pool and produced the crater-like microdefects on the metal surface. The temperature increases due to shock heat and high-speed deformation were not enough to melt the metal target. The temperature increase induced by the adiabatic compression of the air bubbles may also cause the gasification of the metal target. This will also help form the crater-like microdefects. The results of this paper can help to improve the surface quality of a metal target during the application of LSP. In addition, the results provide another method to fabricate 3D crater-like dents on metal surface. This has a potential application in mechanical engineering.

Methods for sulfate removal in liquid-phase catalytic hydrothermal gasification of biomass

DOEpatents

Elliott, Douglas C; Oyler, James R

2014-11-04

Processing of wet biomass feedstock by liquid-phase catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a pre-treatment temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent removal of soluble sulfate contaminants, or combinations thereof. Processing further includes reacting the soluble sulfate contaminants with cations present in the feedstock material to yield a sulfate-containing precipitate and separating the inorganic precipitates and/or the sulfate-containing precipitates out of the wet feedstock. Having removed much of the inorganic wastes and the sulfate contaminants that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogeneous catalyst for gasification.

Methods for sulfate removal in liquid-phase catalytic hydrothermal gasification of biomass

DOEpatents

Elliott, Douglas C; Oyler, James

2013-12-17

Processing of wet biomass feedstock by liquid-phase catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a pre-treatment temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent removal of soluble sulfate contaminants, or combinations thereof. Processing further includes reacting the soluble sulfate contaminants with cations present in the feedstock material to yield a sulfate-containing precipitate and separating the inorganic precipitates and/or the sulfate-containing precipitates out of the wet feedstock. Having removed much of the inorganic wastes and the sulfate contaminants that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogenous catalyst for gasification.

Solar heated fluidized bed gasification system

NASA Technical Reports Server (NTRS)

Qader, S. A. (Inventor)

1981-01-01

A solar-powered fluidized bed gasification system for gasifying carbonaceous material is presented. The system includes a solar gasifier which is heated by fluidizing gas and steam. Energy to heat the gas and steam is supplied by a high heat capacity refractory honeycomb which surrounds the fluid bed reactor zone. The high heat capacity refractory honeycomb is heated by solar energy focused on the honeycomb by solar concentrator through solar window. The fluid bed reaction zone is also heated directly and uniformly by thermal contact of the high heat capacity ceramic honeycomb with the walls of the fluidized bed reactor. Provisions are also made for recovering and recycling catalysts used in the gasification process. Back-up furnace is provided for start-up procedures and for supplying heat to the fluid bed reaction zone when adequate supplies of solar energy are not available.

A Hydrodynamic Characteristic of a Dual Fluidized Bed Gasification

NASA Astrophysics Data System (ADS)

Sung, Yeon Kyung; Song, Jae Hun; Bang, Byung Ryeul; Yu, Tae U.; Lee, Uen Do

A cold model dual fluidized bed (DFB) reactor, consisting of two parallel interconnected bubbling and fast fluidized beds, was designed for developing an auto-thermal biomass gasifier. The combustor of this system burns the rest char of the gasification process and provides heat to the gasifier by circulating solids inventory. To find an optimal mixing and circulation of heavy solid inventory and light biomass and char materials, we investigate two types of DFB reactors which have different configuration of distributor and way-out location of the solid inventory and char materials in the gasifier. To determine appropriate operating conditions, we measured minimum fluidization velocity, solid circulation rate, axial solid holdup and gas bypassing between the lower loop seal and the gasifier.

Gasification Characteristics of Coal/Biomass Mixed Fuels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mitchell, Reginald

2014-09-01

A research project was undertaken that had the overall objective of developing the models needed to accurately predict conversion rates of coal/biomass mixtures to synthesis gas under conditions relevant to a commercially-available coal gasification system configured to co-produce electric power as well as chemicals and liquid fuels. In our efforts to accomplish this goal, experiments were performed in an entrained flow reactor in order to produce coal and biomass chars at high heating rates and temperatures, typical of the heating rates and temperatures fuel particles experience in real systems. Mixed chars derived from coal/biomass mixtures containing up to 50% biomassmore » and the chars of the pure coal and biomass components were subjected to a matrix of reactivity tests in a pressurized thermogravimetric analyzer (TGA) in order to obtain data on mass loss rates as functions of gas temperature, pressure and composition as well as to obtain information on the variations in mass specific surface area during char conversion under kinetically-limited conditions. The experimental data were used as targets when determining the unknown parameters in the chemical reactivity and specific surface area models developed. These parameters included rate coefficients for the reactions in the reaction mechanism, enthalpies of formation and absolute entropies of adsorbed species formed on the carbonaceous surfaces, and pore structure coefficients in the model used to describe how the mass specific surface area of the char varies with conversion. So that the reactivity models can be used at high temperatures when mass transport processes impact char conversion rates, Thiele modulus – effectiveness factor relations were also derived for the reaction mechanisms developed. In addition, the reactivity model and a mode of conversion model were combined in a char-particle gasification model that includes the effects of chemical reaction and diffusion of reactive gases through particle pores and energy exchange between the particle and its environment. This char-particle gasification model is capable of predicting the average mass loss rates, sizes, apparent densities, specific surface areas, and temperatures of the char particles produced when co-firing coal and biomass to the type environments established in entrained flow gasifiers operating at high temperatures and elevated pressures.« less

Characterization of Thermo-Physical Properties of EVA/ATH: Application to Gasification Experiments and Pyrolysis Modeling.

PubMed

Girardin, Bertrand; Fontaine, Gaëlle; Duquesne, Sophie; Försth, Michael; Bourbigot, Serge

2015-11-20

The pyrolysis of solid polymeric materials is a complex process that involves both chemical and physical phenomena such as phase transitions, chemical reactions, heat transfer, and mass transport of gaseous components. For modeling purposes, it is important to characterize and to quantify the properties driving those phenomena, especially in the case of flame-retarded materials. In this study, protocols have been developed to characterize the thermal conductivity and the heat capacity of an ethylene-vinyl acetate copolymer (EVA) flame retarded with aluminum tri-hydroxide (ATH). These properties were measured for the various species identified across the decomposition of the material. Namely, the thermal conductivity was found to decrease as a function of temperature before decomposition whereas the ceramic residue obtained after the decomposition at the steady state exhibits a thermal conductivity as low as 0.2 W/m/K. The heat capacity of the material was also investigated using both isothermal modulated Differential Scanning Calorimetry (DSC) and the standard method (ASTM E1269). It was shown that the final residue exhibits a similar behavior to alumina, which is consistent with the decomposition pathway of EVA/ATH. Besides, the two experimental approaches give similar results over the whole range of temperatures. Moreover, the optical properties before decomposition and the heat capacity of the decomposition gases were also analyzed. Those properties were then used as input data for a pyrolysis model in order to predict gasification experiments. Mass losses of gasification experiments were well predicted, thus validating the characterization of the thermo-physical properties of the material.

Characterization of Thermo-Physical Properties of EVA/ATH: Application to Gasification Experiments and Pyrolysis Modeling

PubMed Central

Girardin, Bertrand; Fontaine, Gaëlle; Duquesne, Sophie; Försth, Michael; Bourbigot, Serge

2015-01-01

The pyrolysis of solid polymeric materials is a complex process that involves both chemical and physical phenomena such as phase transitions, chemical reactions, heat transfer, and mass transport of gaseous components. For modeling purposes, it is important to characterize and to quantify the properties driving those phenomena, especially in the case of flame-retarded materials. In this study, protocols have been developed to characterize the thermal conductivity and the heat capacity of an ethylene-vinyl acetate copolymer (EVA) flame retarded with aluminum tri-hydroxide (ATH). These properties were measured for the various species identified across the decomposition of the material. Namely, the thermal conductivity was found to decrease as a function of temperature before decomposition whereas the ceramic residue obtained after the decomposition at the steady state exhibits a thermal conductivity as low as 0.2 W/m/K. The heat capacity of the material was also investigated using both isothermal modulated Differential Scanning Calorimetry (DSC) and the standard method (ASTM E1269). It was shown that the final residue exhibits a similar behavior to alumina, which is consistent with the decomposition pathway of EVA/ATH. Besides, the two experimental approaches give similar results over the whole range of temperatures. Moreover, the optical properties before decomposition and the heat capacity of the decomposition gases were also analyzed. Those properties were then used as input data for a pyrolysis model in order to predict gasification experiments. Mass losses of gasification experiments were well predicted, thus validating the characterization of the thermo-physical properties of the material. PMID:28793682

Sampling of tar from sewage sludge gasification using solid phase adsorption.

PubMed

Ortiz González, Isabel; Pérez Pastor, Rosa Ma; Sánchez Hervás, José Ma

2012-06-01

Sewage sludge is a residue from wastewater treatment plants which is considered to be harmful to the environment and all living organisms. Gasification technology is a potential source of renewable energy that converts the sewage sludge into gases that can be used to generate energy or as raw material in chemical synthesis processes. But tar produced during gasification is one of the problems for the implementation of the gasification technology. Tar can condense on pipes and filters and may cause blockage and corrosion in the engines and turbines. Consequently, to minimize tar content in syngas, the ability to quantify tar levels in process streams is essential. The aim of this work was to develop an accurate tar sampling and analysis methodology using solid phase adsorption (SPA) in order to apply it to tar sampling from sewage sludge gasification gases. Four types of commercial SPA cartridges have been tested to determine the most suitable one for the sampling of individual tar compounds in such streams. Afterwards, the capacity, breakthrough volume and sample stability of the Supelclean™ ENVI-Carb/NH(2), which is identified as the most suitable, have been determined. Basically, no significant influences from water, H(2)S or NH(3) were detected. The cartridge was used in sampling real samples, and comparable results were obtained with the present and traditional methods.

Properties of gasification-derived char and its utilization for catalytic tar reforming

NASA Astrophysics Data System (ADS)

Qian, Kezhen

Char is a low-value byproduct of biomass gasification and pyrolysis with many potential applications, such as soil amendment and the synthesis of activated carbon. The overall goal of the proposed research was to develop novel methods to use char derived from gasification for high-value applications in syngas conditioning. The first objective was to investigate effects of gasification condition and feedstock on properties of char derived from fluidized bed gasification. Results show that the surface areas of most of the char were 1--10 m 2/g and increased as the equivalence ratio increased. Char moisture and fixed carbon contents decreased while ash content increased as equivalence ratio increased. The next objective was to study the properties of sorghum and red cedar char derived from downdraft gasifier. Red cedar char contained more aliphatic carbon and o-alkyl carbon than sorghum char. Char derived from downdraft gasification had higher heating values and lower ash contents than char derived from fluidized bed gasification. The gasification reactivity of red cedar char was higher than that of sorghum char. Then, red cedar char based catalysts were developed with different preparation method to reform toluene and naphthalene as model tars. The catalyst prepared with nickel nitrate was found to be better than that with nickel acetate. The nickel particle size of catalyst impregnated with nickel nitrate was smaller than that of catalyst impregnated with nickel acetate. The particle size of catalyst impregnated with nickel acetate decreased by hydrazine reduction. The catalyst impregnated with nickel nitrate had the highest toluene removal efficiency, which was 70%--100% at 600--800 °C. The presence of naphthalene in tar reduced the catalyst efficiency. The toluene conversion was 36--99% and the naphthalene conversion was 37%--93% at 700--900 °C. Finally, effects of atmosphere and pressure on catalytic reforming of lignin-derived tars over the developed catalyst were investigated. An increase in reaction temperature led to an increase in removal of most tar components except naphthalene. High pressure promoted the catalytic conditioning of lignin tar. Hydrogen promoted the conversion of lignin into non-condensable gas.

Method of producing pyrolysis gases from carbon-containing materials

DOEpatents

Mudge, Lyle K.; Brown, Michael D.; Wilcox, Wayne A.; Baker, Eddie G.

1989-01-01

A gasification process of improved efficiency is disclosed. A dual bed reactor system is used in which carbon-containing feedstock materials are first treated in a gasification reactor to form pyrolysis gases. The pyrolysis gases are then directed into a catalytic reactor for the destruction of residual tars/oils in the gases. Temperatures are maintained within the catalytic reactor at a level sufficient to crack the tars/oils in the gases, while avoiding thermal breakdown of the catalysts. In order to minimize problems associated with the deposition of carbon-containing materials on the catalysts during cracking, a gaseous oxidizing agent preferably consisting of air, oxygen, steam, and/or mixtures thereof is introduced into the catalytic reactor at a high flow rate in a direction perpendicular to the longitudinal axis of the reactor. This oxidizes any carbon deposits on the catalysts, which would normally cause catalyst deactivation.

Process for gasifying carbonaceous material from a recycled condensate slurry

DOEpatents

Forney, Albert J.; Haynes, William P.

1981-01-01

Coal or other carbonaceous material is gasified by reaction with steam and oxygen in a manner to minimize the problems of effluent water stream disposal. The condensate water from the product gas is recycled to slurry the coal feed and the amount of additional water or steam added for cooling or heating is minimized and preferably kept to a level of about that required to react with the carbonaceous material in the gasification reaction. The gasification is performed in a pressurized fluidized bed with the coal fed in a water slurry and preheated or vaporized by indirect heat exchange contact with product gas and recycled steam. The carbonaceous material is conveyed in a gas-solid mixture from bottom to top of the pressurized fluidized bed gasifier with the solids removed from the product gas and recycled steam in a supported moving bed filter of the resulting carbonaceous char. Steam is condensed from the product gas and the condensate recycled to form a slurry with the feed coal carbonaceous particles.

Controlled Gas Exfoliation of Boron Nitride into Few-Layered Nanosheets

DOE PAGES

Zhu, Wenshuai; Gao, Xiang; Li, Qian; ...

2016-07-22

The controlled exfoliation of hexagonal boron nitride (h-BN) into single- or few-layered nanosheets remains a grand challenge and becomes the bottleneck to essential studies and applications of h-BN. Here, we present an efficient strategy for the scalable synthesis of few-layered h-BN nanosheets (BNNS) via a novel gas exfoliation of bulk h-BN in liquid N 2 (L-N 2). The essence of this strategy lies in the combination of a high temperature triggered expansion of bulk h-BN and the cryogenic L-N 2 gasification to exfoliate the h-BN. The produced BNNS after ten cycles (BNNS-10) consisted primarily of fewer than five atomic layersmore » with high a mass yield of 16~20%. N 2 sorption and desorption isotherms show that the BNNS-10 exhibited a much higher specific surface area of 278 m 2/g –1 than that of bulk BN (10 m 2/g –1). Through the investigation of the exfoliated intermediates combined with a theoretical calculation, we found that the huge temperature variation initiates the expansion and curling of the bulk h-BN. Subseqently, the L-N 2 penetrates into the interlayers of h-BN along the curling edge, followed by an immediate drastic gasification of L-N 2, further peeling off h-BN. In conclusion, this novel gas exfoliation of high surface area BNNS not only opens up potential opportunities for wide applications, but also can be extended to produce other layered materials with high yeilds.« less

Metal catalysts for steam reforming of tar derived from the gasification of lignocellulosic biomass.

PubMed

Li, Dalin; Tamura, Masazumi; Nakagawa, Yoshinao; Tomishige, Keiichi

2015-02-01

Biomass gasification is one of the most important technologies for the conversion of biomass to electricity, fuels, and chemicals. The main obstacle preventing the commercial application of this technology is the presence of tar in the product gas. Catalytic reforming of tar appears a promising approach to remove tar and supported metal catalysts are among the most effective catalysts. Nevertheless, improvement of catalytic performances including activity, stability, resistance to coke deposition and aggregation of metal particles, as well as catalyst regenerability is greatly needed. This review focuses on the design and catalysis of supported metal catalysts for the removal of tar in the gasification of biomass. The recent development of metal catalysts including Rh, Ni, Co, and their alloys for steam reforming of biomass tar and tar model compounds is introduced. The role of metal species, support materials, promoters, and their interfaces is described. Copyright © 2014 Elsevier Ltd. All rights reserved.

Steam gasification of tyre waste, poplar, and refuse-derived fuel: a comparative analysis.

PubMed

Galvagno, S; Casciaro, G; Casu, S; Martino, M; Mingazzini, C; Russo, A; Portofino, S

2009-02-01

In the field of waste management, thermal disposal is a treatment option able to recover resources from "end of life" products. Pyrolysis and gasification are emerging thermal treatments that work under less drastic conditions in comparison with classic direct combustion, providing for reduced gaseous emissions of heavy metals. Moreover, they allow better recovery efficiency since the process by-products can be used as fuels (gas, oils), for both conventional (classic engines and heaters) and high efficiency apparatus (gas turbines and fuel cells), or alternatively as chemical sources or as raw materials for other processes. This paper presents a comparative study of a steam gasification process applied to three different waste types (refuse-derived fuel, poplar wood and scrap tyres), with the aim of comparing the corresponding yields and product compositions and exploring the most valuable uses of the by-products.

Evaluation of a Combined Cyclone and Gas Filtration System for Particulate Removal in the Gasification Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rizzo, Jeffrey J.

2010-04-30

The Wabash gasification facility, owned and operated by sgSolutions LLC, is one of the largest single train solid fuel gasification facilities in the world capable of transforming 2,000 tons per day of petroleum coke or 2,600 tons per day of bituminous coal into synthetic gas for electrical power generation. The Wabash plant utilizes Phillips66 proprietary E-Gas (TM) Gasification Process to convert solid fuels such as petroleum coke or coal into synthetic gas that is fed to a combined cycle combustion turbine power generation facility. During plant startup in 1995, reliability issues were realized in the gas filtration portion of themore » gasification process. To address these issues, a slipstream test unit was constructed at the Wabash facility to test various filter designs, materials and process conditions for potential reliability improvement. The char filtration slipstream unit provided a way of testing new materials, maintenance procedures, and process changes without the risk of stopping commercial production in the facility. It also greatly reduced maintenance expenditures associated with full scale testing in the commercial plant. This char filtration slipstream unit was installed with assistance from the United States Department of Energy (built under DOE Contract No. DE-FC26-97FT34158) and began initial testing in November of 1997. It has proven to be extremely beneficial in the advancement of the E-Gas (TM) char removal technology by accurately predicting filter behavior and potential failure mechanisms that would occur in the commercial process. After completing four (4) years of testing various filter types and configurations on numerous gasification feed stocks, a decision was made to investigate the economic and reliability effects of using a particulate removal gas cyclone upstream of the current gas filtration unit. A paper study had indicated that there was a real potential to lower both installed capital and operating costs by implementing a char cyclonefiltration hybrid unit in the E-Gas (TM) gasification process. These reductions would help to keep the E-Gas (TM) technology competitive among other coal-fired power generation technologies. The Wabash combined cyclone and gas filtration slipstream test program was developed to provide design information, equipment specification and process control parameters of a hybrid cyclone and candle filter particulate removal system in the E-Gas (TM) gasification process that would provide the optimum performance and reliability for future commercial use. The test program objectives were as follows: 1. Evaluate the use of various cyclone materials of construction; 2. Establish the optimal cyclone efficiency that provides stable long term gas filter operation; 3. Determine the particle size distribution of the char separated by both the cyclone and candle filters. This will provide insight into cyclone efficiency and potential future plant design; 4. Determine the optimum filter media size requirements for the cyclone-filtration hybrid unit; 5. Determine the appropriate char transfer rates for both the cyclone and filtration portions of the hybrid unit; 6. Develop operating procedures for the cyclone-filtration hybrid unit; and, 7. Compare the installed capital cost of a scaled-up commercial cyclone-filtration hybrid unit to the current gas filtration design without a cyclone unit, such as currently exists at the Wabash facility.« less

Fluid bed gasification – Plasma converter process generating energy from solid waste: Experimental assessment of sulphur species

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morrin, Shane, E-mail: shane.morrin@ucl.ac.uk; Advanced Plasma Power, Swindon, Wiltshire SN3 4DE; Lettieri, Paola, E-mail: p.lettieri@ucl.ac.uk

2014-01-15

Highlights: • We investigate gaseous sulphur species whilst gasifying sulphur-enriched wood pellets. • Experiments performed using a two stage fluid bed gasifier – plasma converter process. • Notable SO{sub 2} and relatively low COS levels were identified. • Oxygen-rich regions of the bed are believed to facilitate SO{sub 2}, with a delayed release. • Gas phase reducing regions above the bed would facilitate more prompt COS generation. - Abstract: Often perceived as a Cinderella material, there is growing appreciation for solid waste as a renewable content thermal process feed. Nonetheless, research on solid waste gasification and sulphur mechanisms in particularmore » is lacking. This paper presents results from two related experiments on a novel two stage gasification process, at demonstration scale, using a sulphur-enriched wood pellet feed. Notable SO{sub 2} and relatively low COS levels (before gas cleaning) were interesting features of the trials, and not normally expected under reducing gasification conditions. Analysis suggests that localised oxygen rich regions within the fluid bed played a role in SO{sub 2}’s generation. The response of COS to sulphur in the feed was quite prompt, whereas SO{sub 2} was more delayed. It is proposed that the bed material sequestered sulphur from the feed, later aiding SO{sub 2} generation. The more reducing gas phase regions above the bed would have facilitated COS – hence its faster response. These results provide a useful insight, with further analysis on a suite of performed experiments underway, along with thermodynamic modelling.« less

Syngas production by chemical-looping gasification of wheat straw with Fe-based oxygen carrier.

PubMed

Hu, Jianjun; Li, Chong; Guo, Qianhui; Dang, Jiatao; Zhang, Quanguo; Lee, Duu-Jong; Yang, Yunlong

2018-05-03

The iron-based oxygen carriers (OC's), Fe 2 O 3 /support (Al 2 O 3 , TiO 2 , SiO 2 and ZrO 2 ), for chemical looping gasification of wheat straw were prepared using impregnation method. The surface morphology, crystal structure, carbon deposition potential, lattice oxygen activity and selectivity of the yielded OCs were examined. The Fe 2 O 3 /Al 2 O 3 OCs at 60% loading has the highest H 2 yield, H 2 /CO ratio, gas yield, and carbon conversion amongst the tested OC's. Parametric studies revealed that an optimal loading Fe 2 O 3 of 60%, steam-to-biomass ratio of 0.8 and oxygen carrier-to-biomass ratio of 1.0 led to the maximum H 2 /CO ratio, gas yield, H 2  + CO ratio, and carbon conversion from the gasified wheat straw. High temperature, up to 950 °C, enhanced the gasification performance. A kinetic network interpreted the noted experimental results. The lattice oxygen provided by the prepared Fe 2 O 3 /Al 2 O 3 oxygen carriers promotes chemical looping gasification efficiencies from wheat straw. Copyright © 2018 Elsevier Ltd. All rights reserved.

Gasification of high ash, high ash fusion temperature bituminous coals

DOEpatents

Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang

2015-11-13

This invention relates to gasification of high ash bituminous coals that have high ash fusion temperatures. The ash content can be in 15 to 45 weight percent range and ash fusion temperatures can be in 1150.degree. C. to 1500.degree. C. range as well as in excess of 1500.degree. C. In a preferred embodiment, such coals are dealt with a two stage gasification process--a relatively low temperature primary gasification step in a circulating fluidized bed transport gasifier followed by a high temperature partial oxidation step of residual char carbon and small quantities of tar. The system to process such coals further includes an internally circulating fluidized bed to effectively cool the high temperature syngas with the aid of an inert media and without the syngas contacting the heat transfer surfaces. A cyclone downstream of the syngas cooler, operating at relatively low temperatures, effectively reduces loading to a dust filtration unit. Nearly dust- and tar-free syngas for chemicals production or power generation and with over 90%, and preferably over about 98%, overall carbon conversion can be achieved with the preferred process, apparatus and methods outlined in this invention.

The carbon dioxide gasification characteristics of biomass char samples and their effect on coal gasification reactivity during co-gasification.

PubMed

Mafu, Lihle D; Neomagus, Hein W J P; Everson, Raymond C; Okolo, Gregory N; Strydom, Christien A; Bunt, John R

2018-06-01

The carbon dioxide gasification characteristics of three biomass char samples and bituminous coal char were investigated in a thermogravimetric analyser in the temperature range of 850-950 °C. Char SB exhibited higher reactivities (R i , R s , R f ) than chars SW and HW. Coal char gasification reactivities were observed to be lower than those of the three biomass chars. Correlations between the char reactivities and char characteristics were highlighted. The addition of 10% biomass had no significant impact on the coal char gasification reactivity. However, 20 and 30% biomass additions resulted in increased coal char gasification rate. During co-gasification, chars HW and SW caused increased coal char gasification reactivity at lower conversions, while char SB resulted in increased gasification rates throughout the entire conversion range. Experimental data from biomass char gasification and biomass-coal char co-gasification were well described by the MRPM, while coal char gasification was better described by the RPM. Copyright © 2018 Elsevier Ltd. All rights reserved.

Energetic and environmental assessment of thermochemical and biochemical ways for producing energy from agricultural solid residues: Coffee Cut-Stems case.

PubMed

García, Carlos A; Peña, Álvaro; Betancourt, Ramiro; Cardona, Carlos A

2018-06-15

Forest residues are an important source of biomass. Among these, Coffee Cut-Stems (CCS) are an abundant wood waste in Colombia obtained from coffee crops renovation. However, only low quantities of these residues are used directly in combustion processes for heating and cooking in coffee farms where their energy efficiency is very low. In the present work, an energy and environmental assessment of two bioenergy production processes (ethanol fermentation and gasification) using CCS as raw material was performed. Biomass gasification seems to be the most promising thermochemical method for bioenergy production whereas, ethanol fermentation is a widely studied biochemical method to produce biofuels. Experimental runs of the CCS gasification were carried out and the synthesis gas composition was monitored. Prior to the fermentation process, a treatment of the CCS is required from which sugar content was determined and then, in the fermentation process, the ethanol yield was calculated. Both processes were simulated in order to obtain the mass and energy balance that are used to assess the energy efficiency and the potential environmental impact (PEI). Moderate high energy efficiency and low environmental impacts were obtained from the CCS gasification. In contrast, high environmental impacts in different categories and low energy efficiencies were calculated from the ethanolic fermentation. Biomass gasification seems to be the most promising technology for the use of Coffee Cut-Stems with high energy yields and low environmental issues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Gasification Product Improvement Facility (GPIF). Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-09-01

The gasifier selected for development under this contract is an innovative and patented hybrid technology which combines the best features of both fixed-bed and fluidized-bed types. PyGas{trademark}, meaning Pyrolysis Gasification, is well suited for integration into advanced power cycles such as IGCC. It is also well matched to hot gas clean-up technologies currently in development. Unlike other gasification technologies, PyGas can be designed into both large and small scale systems. It is expected that partial repowering with PyGas could be done at a cost of electricity of only 2.78 cents/kWh, more economical than natural gas repowering. It is extremely unfortunatemore » that Government funding for such a noble cause is becoming reduced to the point where current contracts must be canceled. The Gasification Product Improvement Facility (GPIF) project was initiated to provide a test facility to support early commercialization of advanced fixed-bed coal gasification technology at a cost approaching $1,000 per kilowatt for electric power generation applications. The project was to include an innovative, advanced, air-blown, pressurized, fixed-bed, dry-bottom gasifier and a follow-on hot metal oxide gas desulfurization sub-system. To help defray the cost of testing materials, the facility was to be located at a nearby utility coal fired generating site. The patented PyGas{trademark} technology was selected via a competitive bidding process as the candidate which best fit overall DOE objectives. The paper describes the accomplishments to date.« less

Phosphorus distribution in soils amended with bioenergy co-product materials following corn growth

USDA-ARS?s Scientific Manuscript database

Biochar is a carbonaceous co-product that results from pyrolysis of organic material in the absence of oxygen produced for use as a soil amendment. Pyrolysis, gasification, and combustion are three processes being investigated and/or used to convert biomass into renewable energy and other products. ...

Underground gasification of coal

DOEpatents

Pasini, III, Joseph; Overbey, Jr., William K.; Komar, Charles A.

1976-01-20

There is disclosed a method for the gasification of coal in situ which comprises drilling at least one well or borehole from the earth's surface so that the well or borehole enters the coalbed or seam horizontally and intersects the coalbed in a direction normal to its major natural fracture system, initiating burning of the coal with the introduction of a combustion-supporting gas such as air to convert the coal in situ to a heating gas of relatively high calorific value and recovering the gas. In a further embodiment the recovered gas may be used to drive one or more generators for the production of electricity.

Seventh BES (Basic Energy Sciences) catalysis and surface chemistry research conference

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1990-03-01

Research programs on catalysis and surface chemistry are presented. A total of fifty-seven topics are included. Areas of research include heterogeneous catalysis; catalysis in hydrogenation, desulfurization, gasification, and redox reactions; studies of surface properties and surface active sites; catalyst supports; chemical activation, deactivation; selectivity, chemical preparation; molecular structure studies; sorption and dissociation. Individual projects are processed separately for the data bases. (CBS)

Incineration, pyrolysis and gasification of electronic waste

NASA Astrophysics Data System (ADS)

Gurgul, Agnieszka; Szczepaniak, Włodzimierz; Zabłocka-Malicka, Monika

2017-11-01

Three high temperature processes of the electronic waste processing: smelting/incineration, pyrolysis and gasification were shortly discussed. The most distinctive feature of electronic waste is complexity of components and their integration. This type of waste consists of polymeric materials and has high content of valuable metals that could be recovered. The purpose of thermal treatment of electronic waste is elimination of plastic components (especially epoxy resins) while leaving non-volatile mineral and metallic phases in more or less original forms. Additionally, the gaseous product of the process after cleaning may be used for energy recovery or as syngas.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The coal industry, the utilities, and the state government are planning for development of high-energy coal gasification in Illinois to convert its abundant high-sulfur coal supply to a substitute natural gas. Following a summary of the findings, the following topics are discussed briefly: Illinois coal and the push for coal gasification; coal gasification: a look at the process; potential sites for an Illinois coal gasification industry; the impact of coal gasification's water requirements; solid wastes from coal gasification; land losses: the impact on agriculture; potential human health problems with coal gasification; the energy efficiency of coal gasification; potential economic impactsmore » of coal gasification; the corporations behind high-energy coal gasification; state involvement: legalizing the losses of the people; the national energy picture: the impact of western coal developments on Illinois; action: what you can do now. 27 references. (MCW)« less

Hollow glass for insulating layers

NASA Astrophysics Data System (ADS)

Merticaru, Andreea R.; Moagar-Poladian, Gabriel

1999-03-01

Common porous materials, some of which will be considered in the chapters of this book, include concrete, paper, ceramics, clays, porous semiconductors, chromotography materials, and natural materials like coral, bone, sponges, rocks and shells. Porous materials can also be reactive, such as in charcoal gasification, acid rock dissolution, catalyst deactivation and concrete. This study continues the investigations about the properties of, so-called, hollow glass. In this paper is presented a computer simulation approach in which the thermo-mechanical behavior of a 3D microstructure is directly computed. In this paper a computer modeling approach of porous glass is presented. One way to test the accuracy of the reconstructed microstructures is to computed their physical properties and compare to experimental measurement on equivalent systems. In this view, we imagine a new type of porous type of glass designed as buffer layer in multilayered printed boards in ICs. Our glass is a variable material with a variable pore size and surface area. The porosity could be tailored early from the deposition phases that permitting us to keep in a reasonable balance the dielectric constant and thermal conductivity.

Solar gasification of biomass: design and characterization of a molten salt gasification reactor

NASA Astrophysics Data System (ADS)

Hathaway, Brandon Jay

The design and implementation of a prototype molten salt solar reactor for gasification of biomass is a significant milestone in the development of a solar gasification process. The reactor developed in this work allows for 3 kWth operation with an average aperture flux of 1530 suns at salt temperatures of 1200 K with pneumatic injection of ground or powdered dry biomass feedstocks directly into the salt melt. Laboratory scale experiments in an electrically heated reactor demonstrate the benefits of molten salt and the data was evaluated to determine the kinetics of pyrolysis and gasification of biomass or carbon in molten salt. In the presence of molten salt overall gas yields are increased by up to 22%; pyrolysis rates double due to improved heat transfer, while carbon gasification rates increase by an order of magnitude. Existing kinetic models for cellulose pyrolysis fit the data well, while carbon gasification in molten salt follows kinetics modeled with a 2/3 order shrinking-grain model with a pre-exponential factor of 1.5*106 min-1 and activation energy of 158 kJ/mol. A reactor concept is developed based around a concentric cylinder geometry with a cavity-style solar receiver immersed within a volume of molten carbonate salt. Concentrated radiation delivered to the cavity is absorbed in the cavity walls and transferred via convection to the salt volume. Feedstock is delivered into the molten salt volume where biomass gasification reactions will be carried out producing the desired product gas. The features of the cavity receiver/reactor concept are optimized based on modeling of the key physical processes. The cavity absorber geometry is optimized according to a parametric survey of radiative exchange using a Monte Carlo ray tracing model, resulting in a cavity design that achieves absorption efficiencies of 80%-90%. A parametric survey coupling the radiative exchange simulations to a CFD model of molten salt natural convection is used to size the annulus containing the molten salt to maximize utilization of absorbed solar energy, resulting in a predicted utilization efficiency of 70%. Finite element analysis was used to finalize the design to achieve acceptable thermal stresses less than 34.5 MPa to avoid material creep.

Plasma gasification of refuse derived fuel in a single-stage system using different gasifying agents.

PubMed

Agon, N; Hrabovský, M; Chumak, O; Hlína, M; Kopecký, V; Masláni, A; Bosmans, A; Helsen, L; Skoblja, S; Van Oost, G; Vierendeels, J

2016-01-01

The renewable evolution in the energy industry and the depletion of natural resources are putting pressure on the waste industry to shift towards flexible treatment technologies with efficient materials and/or energy recovery. In this context, a thermochemical conversion method of recent interest is plasma gasification, which is capable of producing syngas from a wide variety of waste streams. The produced syngas can be valorized for both energetic (heat and/or electricity) and chemical (ammonia, hydrogen or liquid hydrocarbons) end-purposes. This paper evaluates the performance of experiments on a single-stage plasma gasification system for the treatment of refuse-derived fuel (RDF) from excavated waste. A comparative analysis of the syngas characteristics and process yields was done for seven cases with different types of gasifying agents (CO2+O2, H2O, CO2+H2O and O2+H2O). The syngas compositions were compared to the thermodynamic equilibrium compositions and the performance of the single-stage plasma gasification of RDF was compared to that of similar experiments with biomass and to the performance of a two-stage plasma gasification process with RDF. The temperature range of the experiment was from 1400 to 1600 K and for all cases, a medium calorific value syngas was produced with lower heating values up to 10.9 MJ/Nm(3), low levels of tar, high levels of CO and H2 and which composition was in good agreement to the equilibrium composition. The carbon conversion efficiency ranged from 80% to 100% and maximum cold gas efficiency and mechanical gasification efficiency of respectively 56% and 95%, were registered. Overall, the treatment of RDF proved to be less performant than that of biomass in the same system. Compared to a two-stage plasma gasification system, the produced syngas from the single-stage reactor showed more favourable characteristics, while the recovery of the solid residue as a vitrified slag is an advantage of the two-stage set-up. Copyright © 2015 Elsevier Ltd. All rights reserved.

Regeneration of glass nanofluidic chips through a multiple-step sequential thermochemical decomposition process at high temperatures.

PubMed

Xu, Yan; Wu, Qian; Shimatani, Yuji; Yamaguchi, Koji

2015-10-07

Due to the lack of regeneration methods, the reusability of nanofluidic chips is a significant technical challenge impeding the efficient and economic promotion of both fundamental research and practical applications on nanofluidics. Herein, a simple method for the total regeneration of glass nanofluidic chips was described. The method consists of sequential thermal treatment with six well-designed steps, which correspond to four sequential thermal and thermochemical decomposition processes, namely, dehydration, high-temperature redox chemical reaction, high-temperature gasification, and cooling. The method enabled the total regeneration of typical 'dead' glass nanofluidic chips by eliminating physically clogged nanoparticles in the nanochannels, removing chemically reacted organic matter on the glass surface and regenerating permanent functional surfaces of dissimilar materials localized in the nanochannels. The method provides a technical solution to significantly improve the reusability of glass nanofluidic chips and will be useful for the promotion and acceleration of research and applications on nanofluidics.

Effect of torrefaction on the properties of rice straw high temperature pyrolysis char: Pore structure, aromaticity and gasification activity.

PubMed

Chen, Handing; Chen, Xueli; Qin, Yueqiang; Wei, Juntao; Liu, Haifeng

2017-03-01

The influence of torrefaction on the physicochemical characteristics of char during raw and water washed rice straw pyrolysis at 800-1200°C is investigated. Pore structure, aromaticity and gasification activity of pyrolysis chars are compared between raw and torrefied samples. For raw straw, BET specific surface area decreases with the increased torrefaction temperature at the same pyrolysis temperature and it approximately increases linearly with weight loss during pyrolysis. The different pore structure evolutions relate to the different volatile matters and pore structures between raw and torrefied straw. Torrefaction at higher temperature would bring about a lower graphitization degree of char during pyrolysis of raw straw. Pore structure and carbon crystalline structure evolutions of raw and torrefied water washed straw are different from these of raw straw during pyrolysis. For both raw and water washed straw, CO 2 gasification activities of pyrolysis chars are different between raw and torrefied samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gasification of oil palm empty fruit bunches: a characterization and kinetic study.

PubMed

Mohammed, M A A; Salmiaton, A; Wan Azlina, W A K G; Mohamad Amran, M S

2012-04-01

Empty fruit bunches (EFBs), a waste material from the palm oil industry, were subjected to pyrolysis and gasification. A high content of volatiles (>82%) increased the reactivity of EFBs, and more than 90% decomposed at 700°C; however, a high content of moisture (>50%) and oxygen (>45%) resulted in a low calorific value. Thermogravimetric analysis demonstrated that the higher the heating rate and the smaller the particle size, the higher the peak and final reaction temperatures. The least squares estimation for a first-order reaction model was used to study the degradation kinetics. The values of activation energy increased from 61.14 to 73.76 and from 40.06 to 47.99kJ/mol when the EFB particle size increased from 0.3 to 1.0mm for holocellulose and lignin degradation stages, respectively. The fuel characteristics of EFB are comparable to those of other biomasses and EFB can be considered a good candidate for gasification. Copyright © 2012 Elsevier Ltd. All rights reserved.

Pyrolysis of coal

DOEpatents

Babu, Suresh P.; Bair, Wilford G.

1992-01-01

A method for mild gasification of crushed coal in a single vertical elongated reaction vessel providing a fluidized bed reaction zone, a freeboard reaction zone, and an entrained reaction zone within the single vessel. Feed coal and gas may be fed separately to each of these reaction zones to provide different reaction temperatures and conditions in each reaction zone. The reactor and process of this invention provides for the complete utilization of a coal supply for gasification including utilization of caking and non-caking or agglomerating feeds in the same reactor. The products may be adjusted to provide significantly greater product economic value, especially with respect to desired production of char having high surface area.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Coal, poultry litter, contaminated corn, rice hulls, moldly hay, manure sludge - these are representative materials that could be tested as fuel feedstocks in a hybrid gasification/combustion concept studied in a recent US Department of Energy (DOE) design project. DOE's National Energy Technology Laboratory (NETL) and the US Department of Agriculture (USDA) collaborated to develop a design concept of a power system that incorporates Hybrid Biomass Gasification. This system would explore the use of a wide range of biomass and agricultural waste products as gasifier feedstocks. The plant, if built, would supply one-third of electrical and steam heating needs atmore » the USDA's Beltsville (Maryland) Agricultural Research Center. 1 fig., 1 photo.« less

Separation of particulate from flue gas of fossil fuel combustion and gasification

DOEpatents

Yang, W.C.; Newby, R.A.; Lippert, T.E.

1997-08-05

The gas from combustion or gasification of fossil fuel contains fly ash and other particulates. The fly ash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The fly ash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured fly ash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled. 11 figs.

Separation of particulate from flue gas of fossil fuel combustion and gasification

DOEpatents

Yang, Wen-Ching; Newby, Richard A.; Lippert, Thomas E.

1997-01-01

The gas from combustion or gasification of fossil fuel contains flyash and other particulate. The flyash is separated from the gas in a plurality of standleg moving granular-bed filter modules. Each module includes a dipleg through which the bed media flows into the standleg. The bed media forms a first filter bed having an upper mass having a first frusto-conical surface in a frusto-conical member at the entrance to the standleg and a lower mass having a second frusto-conical surface of substantially greater area than the first surface after it passes through the standleg. A second filter media bed may be formed above the first filter media bed. The gas is fed tangentially into the module above the first surface. The flyash is captured on the first frusto-conical surface and within the bed mass. The processed gas flows out through the second frusto-conical surface and then through the second filter bed, if present. The bed media is cleaned of the captured flyash and recirculated to the moving granular bed filter. Alternatively, the bed media may be composed of the ash from the combustion which is pelletized to form agglomerates. The ash flows through the bed only once; it is not recycled.

Co-gasification of bituminous coal and hydrochar derived from municipal solid waste: Reactivity and synergy.

PubMed

Wei, Juntao; Guo, Qinghua; He, Qing; Ding, Lu; Yoshikawa, Kunio; Yu, Guangsuo

2017-09-01

In this work, the influences of gasification temperature and blended ratio on co-gasification reactivity and synergy of Shenfu bituminous coal (SF) and municipal solid waste-derived hydrochar (HTC) were investigated using TGA. Additionally, active alkaline and alkaline earth metal (AAEM) transformation during co-gasification was quantitatively analyzed by inductively coupled plasma optical emission spectrometer for correlating synergy on co-gasification reactivity. The results showed that higher char gasification reactivity existed at higher HTC char proportion and gasification temperature, and the main synergy behaviour on co-gasification reactivity was performed as synergistic effect. Enhanced synergistic effect at lower temperature was mainly resulted from more obviously inhibiting the primary AAEM (i.e. active Ca) transformation, and weak synergistic effect still existed at higher temperature since more active K with prominent catalysis was retained. Furthermore, more active HTC-derived AAEM remaining in SF sample during co-gasification would lead to enhanced synergistic effect as HTC char proportion increased. Copyright © 2017 Elsevier Ltd. All rights reserved.

40 CFR 60.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the purpose of providing steam to a steam-electric generator that would produce electrical energy for... divided solid or liquid material, other than uncombined water, as measured by the reference methods...: atmospheric or pressurized fluidized bed combustion, integrated gasification combined cycle...

Experiment Investigation of the Influencing Factors on Bed Agglomeration During Fluidized-Bed Gasification of Biomass Fuels

NASA Astrophysics Data System (ADS)

Chen, Y. Q.; Chen, H. P.; Yang, H. P.; Wang, X. H.; Zhang, S. H.

With the depleting of fossil fuel and environmental polluting increasing, the utilization of biomass resources caught increasing concern. Biomass gasification in fluidized bed, as one promising technology, developed quickly. However, serious agglomeration was displayed as biomass ash reacted with bed material (silica sand) at higher temperature. It hindered the wide utilization of CFB gasifier. The objective ofthis work is to investigate the agglomeration behavior between biomass ash and silica sand, and catch the inherent mechanism. Firstly, the influence of ash compounds on the agglomeration behavior was analyzed with biomass ash and synthesis ash compounds addition in fixed bed as ash sample mixed with bed material evenly before every trial. The reaction temperature was set 850°C that is the operated temperature for many fluidized bed gasificated biomass fuels. Then the influence of reaction time was analyzed. The characteristics of the agglomerated silica sand particles were analyzed by the XRD. Finally, it was simulated with HSC computer mode based on thermodynamic equilibrium. It was observed that when the ratio of the biomass ash to the silica sand was above 0.2, the agglomeration was observed. With the increase of the reaction time, more silica sand particles agglomerated with the biomass ash. There are two kinds of silicate eutecticum investigated by the XRD. It is of great significance for the running ofCFB biomass gasifier and the development ofbiomass utilization technology.

A critical review on sustainable biochar system through gasification: Energy and environmental applications.

PubMed

You, Siming; Ok, Yong Sik; Chen, Season S; Tsang, Daniel C W; Kwon, Eilhann E; Lee, Jechan; Wang, Chi-Hwa

2017-12-01

This review lays great emphasis on production and characteristics of biochar through gasification. Specifically, the physicochemical properties and yield of biochar through the diverse gasification conditions associated with various types of biomass were extensively evaluated. In addition, potential application scenarios of biochar through gasification were explored and their environmental implications were discussed. To qualitatively evaluate biochar sustainability through the gasification process, all gasification products (i.e., syngas and biochar) were evaluated via life cycle assessment (LCA). A concept of balancing syngas and biochar production for an economically and environmentally feasible gasification system was proposed and relevant challenges and solutions were suggested in this review. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental and numerical study of steam gasification of a single charcoal particle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mermoud, F.; Van de Steene, L.; Golfier, F.

2006-04-15

The present work deals with a study coupling experiments and modeling of charcoal gasification by steam at large particle scale. A reliable set of experiments was first established using a specially developed 'macro-TG' apparatus where a particle was suspended and continuously weighed during its gasification. The main control parameters of a fixed-bed process were modified separately: steam gasification of beech charcoal spheres of different diameters (10 to 30 mm) was studied at different temperatures (830 to 1030{sup o}C), different steam partial pressures (0.1 to 0.4 atm H{sub 2}O), and different gas velocities around the particle (0.09 to 0.30 m/s). Simulationsmore » with the particle model were performed for each case. Confrontations with experimental data indicate that the model predictions are both qualitatively and quantitatively satisfactory, with an accuracy of 7%, until 60% of conversion, despite the fact that the phenomena of reactive surface evolution and particle fracturing are not well understood. Anisotropy and peripheral fragmentation make the end of the process difficult to simulate. Finally, an analysis of the thermochemical situation is proposed: it is demonstrated that the usual homogeneous or shrinking core particle models are not satisfying and that only the assumption of thermal equilibrium between the particle and the surrounding gas is valid for a model at bed scale. (author)« less

Study on tar generated from downdraft gasification of oil palm fronds.

PubMed

Atnaw, Samson Mekbib; Kueh, Soo Chuan; Sulaiman, Shaharin Anwar

2014-01-01

One of the most challenging issues concerning the gasification of oil palm fronds (OPF) is the presence of tar and particulates formed during the process considering its high volatile matter content. In this study, a tar sampling train custom built based on standard tar sampling protocols was used to quantify the gravimetric concentration of tar (g/Nm3) in syngas produced from downdraft gasification of OPF. The amount of char, ash, and solid tar produced from the gasification process was measured in order to account for the mass and carbon conversion efficiency. Elemental analysis of the char and solid tar samples was done using ultimate analysis machine, while the relative concentration of the different compounds in the liquid tar was determined making use of a liquid gas chromatography (GC) unit. Average tar concentration of 4.928 g/Nm3 and 1.923 g/Nm3 was obtained for raw gas and cleaned gas samples, respectively. Tar concentration in the raw gas sample was found to be higher compared to results for other biomass materials, which could be attributed to the higher volatile matter percentage of OPF. Average cleaning efficiency of 61% which is comparable to that of sand bed filter and venturi scrubber cleaning systems reported in the literature was obtained for the cleaning system proposed in the current study.

Study on Tar Generated from Downdraft Gasification of Oil Palm Fronds

PubMed Central

Atnaw, Samson Mekbib; Kueh, Soo Chuan; Sulaiman, Shaharin Anwar

2014-01-01

One of the most challenging issues concerning the gasification of oil palm fronds (OPF) is the presence of tar and particulates formed during the process considering its high volatile matter content. In this study, a tar sampling train custom built based on standard tar sampling protocols was used to quantify the gravimetric concentration of tar (g/Nm3) in syngas produced from downdraft gasification of OPF. The amount of char, ash, and solid tar produced from the gasification process was measured in order to account for the mass and carbon conversion efficiency. Elemental analysis of the char and solid tar samples was done using ultimate analysis machine, while the relative concentration of the different compounds in the liquid tar was determined making use of a liquid gas chromatography (GC) unit. Average tar concentration of 4.928 g/Nm3 and 1.923 g/Nm3 was obtained for raw gas and cleaned gas samples, respectively. Tar concentration in the raw gas sample was found to be higher compared to results for other biomass materials, which could be attributed to the higher volatile matter percentage of OPF. Average cleaning efficiency of 61% which is comparable to that of sand bed filter and venturi scrubber cleaning systems reported in the literature was obtained for the cleaning system proposed in the current study. PMID:24526899

Thermodynamic modelling and solar reactor design for syngas production through SCWG of algae

NASA Astrophysics Data System (ADS)

Venkataraman, Mahesh B.; Rahbari, Alireza; Pye, John

2017-06-01

Conversion of algal biomass into value added products, such as liquid fuels, using solar-assisted supercritical water gasification (SCWG) offers a promising approach for clean fuel production. SCWG has significant advantages over conventional gasification in terms of flexibility of feedstock, faster intrinsic kinetics and lower char formation. A relatively unexplored avenue in SCWG is the use of non-renewable source of energy for driving the endothermic gasification. The use of concentrated solar thermal to provide the process heat is attractive, especially in the case of expensive feedstocks such as algae. This study attempts to identify the key parameters and constraints in designing a solar cavity receiver/reactor for on-sun SCWG of algal biomass. A tubular plug-flow reactor, operating at 24 MPa and 400-600 °C with a solar input of 20MWth is modelled. Solar energy is utilized to increase the temperature of the reaction medium (10 wt.% algae solution) from 400 to 605 °C and simultaneously drive the gasification. The model additionally incorporates material constraints based on the allowable stresses for a commercially available Ni-based alloy (Inconel 625), and exergy accounting for the cavity reactor. A parametric evaluation of the steady state performance and quantification of the losses through wall conduction, external radiation and convection, internal convection, frictional pressure drop, mixing and chemical irreversibility, is presented.

Influence of Fuel Moisture Content and Reactor Temperature on the Calorific Value of Syngas Resulted from Gasification of Oil Palm Fronds

PubMed Central

Atnaw, Samson Mekbib; Sulaiman, Shaharin Anwar; Yusup, Suzana

2014-01-01

Biomass wastes produced from oil palm mills and plantations include empty fruit bunches (EFBs), shells, fibers, trunks, and oil palm fronds (OPF). EFBs and shells are partially utilized as boiler fuel while the rest of the biomass materials like OPF have not been utilized for energy generation. No previous study has been reported on gasification of oil palm fronds (OPF) biomass for the production of fuel gas. In this paper, the effect of moisture content of fuel and reactor temperature on downdraft gasification of OPF was experimentally investigated using a lab scale gasifier of capacity 50 kW. In addition, results obtained from equilibrium model of gasification that was developed for facilitating the prediction of syngas composition are compared with experimental data. Comparison of simulation results for predicting calorific value of syngas with the experimental results showed a satisfactory agreement with a mean error of 0.1 MJ/Nm3. For a biomass moisture content of 29%, the resulting calorific value for the syngas was found to be only 2.63 MJ/Nm3, as compared to nearly double (4.95 MJ/Nm3) for biomass moisture content of 22%. A calorific value as high as 5.57 MJ/Nm3 was recorded for higher oxidation zone temperature values. PMID:24578617

Influence of fuel moisture content and reactor temperature on the calorific value of syngas resulted from gasification of oil palm fronds.

PubMed

Atnaw, Samson Mekbib; Sulaiman, Shaharin Anwar; Yusup, Suzana

2014-01-01

Biomass wastes produced from oil palm mills and plantations include empty fruit bunches (EFBs), shells, fibers, trunks, and oil palm fronds (OPF). EFBs and shells are partially utilized as boiler fuel while the rest of the biomass materials like OPF have not been utilized for energy generation. No previous study has been reported on gasification of oil palm fronds (OPF) biomass for the production of fuel gas. In this paper, the effect of moisture content of fuel and reactor temperature on downdraft gasification of OPF was experimentally investigated using a lab scale gasifier of capacity 50 kW. In addition, results obtained from equilibrium model of gasification that was developed for facilitating the prediction of syngas composition are compared with experimental data. Comparison of simulation results for predicting calorific value of syngas with the experimental results showed a satisfactory agreement with a mean error of 0.1 MJ/Nm³. For a biomass moisture content of 29%, the resulting calorific value for the syngas was found to be only 2.63 MJ/Nm³, as compared to nearly double (4.95 MJ/Nm³) for biomass moisture content of 22%. A calorific value as high as 5.57 MJ/Nm³ was recorded for higher oxidation zone temperature values.

Theoretical Investigation of the Process of Steam-Oxygen Gasification of Coke-Ash Particles in a Fluidized Bed Under Pressure

NASA Astrophysics Data System (ADS)

Rokhman, B. B.

2015-03-01

The problem on the evolution of the state of an ensemble of reacting coke-ash particles in a fluidized-bed gas generator is considered. A kinetic equation for the distribution function of particles within small ranges of carbon concentration variation for the stages of surface and bulk reaction has been constructed and integrated. Boundary conditions ("matching" conditions) at the boundaries between these ranges are formulated. The influence of the granulometric composition of the starting coal, height, porosity, and of the bed temperature on the process of steam-oxygen gasification of coke-ash particles of individual sorts of fuel and of a binary coal mixture has been investigated.

Coal gasification vessel

DOEpatents

Loo, Billy W.

1982-01-01

A vessel system (10) comprises an outer shell (14) of carbon fibers held in a binder, a coolant circulation mechanism (16) and control mechanism (42) and an inner shell (46) comprised of a refractory material and is of light weight and capable of withstanding the extreme temperature and pressure environment of, for example, a coal gasification process. The control mechanism (42) can be computer controlled and can be used to monitor and modulate the coolant which is provided through the circulation mechanism (16) for cooling and protecting the carbon fiber and outer shell (14). The control mechanism (42) is also used to locate any isolated hot spots which may occur through the local disintegration of the inner refractory shell (46).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tam, M.S.; Antal, M.J. Jr.

A novel, three-step process for the production of high-quality activated carbons from macadamia nut shell and coconut shell charcoals is described. In this process the charcoal is (1) heated to a high temperature (carbonized), (2) oxidized in air following a stepwise heating program from low (ca. 450 K) to high (ca. 660 K) temperatures (oxygenated), and (3) heated again in an inert environment to a high temperature (activated). By use of this procedure, activated carbons with surface areas greater than 1,000 m{sub 2}/g are manufactured with an overall yield of 15% (based on the dry shell feed). Removal of carbonmore » mass by the development of mesopores and macropores is largely responsible for increases in the surface area of the carbons above 600 m{sub 2}/g. Thus, the surface area per gram of activated carbon can be represented by an inverse function of the yield for burnoffs between 15 and 60%. These findings are supported by mass-transfer calculations and pore-size distribution measurements. A kinetic model for gasification of carbon by oxygen, which provides for an Eley-Rideal type reaction of a surface oxide with oxygen in air, fits the measured gasification rates reasonably well over the temperature range of 550--660 K.« less

SULFUR TOLERANT CATALYSTS FOR BIOMASS TAR REMOVAL - PHASE I

EPA Science Inventory

In this Small Business Innovation Research (SBIR) project, NexTech Materials proposes a catalytic reforming approach to remove waste tar from gasified biomass on nickel-based catalysts. Biomass gasification is a potential renewable route to producing electricity, liquid fue...

Considerations on coal gasification

NASA Technical Reports Server (NTRS)

Franzen, J. E.

1978-01-01

Commercial processes for the gasification of coal with oxygen are discussed. The Koppers-Totzek process for the gasification of coal dust entrained in a stream of gasifying agents is described in particular detail. The outlook for future applications of coal gasification is presented.

Chemical process modelling of Underground Coal Gasification (UCG) and evaluation of produced gas quality for end use

NASA Astrophysics Data System (ADS)

Korre, Anna; Andrianopoulos, Nondas; Durucan, Sevket

2015-04-01

Underground Coal Gasification (UCG) is an unconventional method for recovering energy from coal resources through in-situ thermo-chemical conversion to gas. In the core of the UCG lays the coal gasification process which involves the engineered injection of a blend of gasification agents into the coal resource and propagating its gasification. Athough UCG technology has been known for some time and considered a promising method for unconventional fossil fuel resources exploitation, there are limited modelling studies which achieve the necessary accuracy and realistic simulation of the processes involved. This paper uses the existing knowledge for surface gasifiers and investigates process designs which could be adapted to model UCG. Steady state simulations of syngas production were developed using the Advanced System for Process ENgineering (Aspen) Plus software. The Gibbs free energy minimisation method was used to simulate the different chemical reactor blocks which were combined using a FORTRAN code written. This approach facilitated the realistic simulation of the gasification process. A number of model configurations were developed to simulate different subsurface gasifier layouts considered for the exploitation of underground coal seams. The two gasifier layouts considered here are the linked vertical boreholes and the controlled retractable injection point (CRIP) methods. Different stages of the UCG process (i.e. initialisation, intermediate, end-phase) as well as the temperature level of the syngas collection point in each layout were found to be the two most decisive and distinctive parameters during the design of the optimal model configuration for each layout. Sensitivity analyses were conducted to investigate the significance of the operational parameters and the performance indicators used to evaluate the results. The operational parameters considered were the type of reagents injected (i.e. O2, N2, CO2, H2O), the ratio between the injected reagents and the feedstock quantity (i.e. coal), the pressure, the gasification and the combustion temperatures. The performance indicators included the composition and the energy content of the product gas as well as the carbon and energy efficiency achieved under each operational scenario. Different operational scenarios for every model configuration facilitated the cross-comparison among different configurations. The proximate and ultimate analysis data for the coal seams modelled were taken from a number of candidate UCG sites (Durucan et al., 2014) .The model findings were validated using the results of field trials reported in the literature. It was found that, increased gasification temperature leads to higher H2 and CO quantities in the product gas. Moreover, CH4 and CO2 concentrations increased as reaction pressure increased, while the CH4 quantity reached its highest value at the highest operational pressure, when combined with the lowest gasification temperature. The simulation models developed can be used to design and validate experimental UCG studies and offer significant advantages in terms of time and resource savings. As the UCG process consists of interrelated stages and a number of diverse phenomena, therefore, the gasification designs developed could act as the basis for an integrated UCG model tailored to the needs of a UCG pilot plant.

Synergistic effect on co-gasification reactivity of biomass-petroleum coke blended char.

PubMed

Wei, Juntao; Guo, Qinghua; Gong, Yan; Ding, Lu; Yu, Guangsuo

2017-06-01

In this work, effects of gasification temperature (900°C-1100°C) and blended ratio (3:1, 1:1, 1:3) on reactivity of petroleum coke and biomass co-gasification were studied in TGA. Quantification analysis of active AAEM transformation and in situ investigation of morphological structure variations in gasification were conducted respectively using inductively coupled plasma optical emission spectrometer and heating stage microscope to explore synergistic effect on co-gasification reactivity. The results indicated that char gasification reactivity was enhanced with increasing biomass proportion and gasification temperature. Synergistic effect on co-gasification reactivity was presented after complete generation of biomass ash, and gradually weakened with increasing temperature from 1000°C to 1100°C after reaching the most significant value at 1000°C. This phenomenon was well related with the appearance of molten biomass ash rich in glassy state potassium and the weakest inhibition effect on active potassium transformation during co-gasification at the temperature higher than 1000°C. Copyright © 2017 Elsevier Ltd. All rights reserved.

Waste-to-Energy Decision Support Method for Forward Deployed Forces

DTIC Science & Technology

2014-03-27

15 Gasification ...stable electrical source to generate the plasma. Thermal WTE technology includes three subtypes called incineration, gasification , and pyrolysis...unfavorable public perception associated with the emissions produced by the technology. Gasification Gasification is a thermal process in which

Market Assessment of Biomass Gasification and Combustion Technology for Small- and Medium-Scale Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterson, D.; Haase, S.

2009-07-01

This report provides a market assessment of gasification and direct combustion technologies that use wood and agricultural resources to generate heat, power, or combined heat and power (CHP) for small- to medium-scale applications. It contains a brief overview of wood and agricultural resources in the U.S.; a description and discussion of gasification and combustion conversion technologies that utilize solid biomass to generate heat, power, and CHP; an assessment of the commercial status of gasification and combustion technologies; a summary of gasification and combustion system economics; a discussion of the market potential for small- to medium-scale gasification and combustion systems; andmore » an inventory of direct combustion system suppliers and gasification technology companies. The report indicates that while direct combustion and close-coupled gasification boiler systems used to generate heat, power, or CHP are commercially available from a number of manufacturers, two-stage gasification systems are largely in development, with a number of technologies currently in demonstration. The report also cites the need for a searchable, comprehensive database of operating combustion and gasification systems that generate heat, power, or CHP built in the U.S., as well as a national assessment of the market potential for the systems.« less

Removal of phenol by powdered activated carbon prepared from coal gasification tar residue.

PubMed

Wang, Xiong-Lei; Shen, Jun; Niu, Yan-Xia; Wang, Yu-Gao; Liu, Gang; Sheng, Qing-Tao

2018-03-01

Coal gasification tar residue (CGTR) is a kind of environmentally hazardous byproduct generated in fixed-bed coal gasification process. The CGTR extracted by ethyl acetate was used to prepare powdered activated carbon (PAC), which is applied later for adsorption of phenol. The results showed that the PAC prepared under optimum conditions had enormous mesoporous structure, and the iodine number reached 2030.11 mg/g, with a specific surface area of 1981 m 2 /g and a total pore volume of 0.92 ml/g. Especially, without loading other substances, the PAC, having a strong magnetism, can be easily separated after it adsorbs phenol. The adsorption of phenol by PAC was studied as functions of contact time, temperature, PAC dosage, solution concentration and pH. The results showed a fast adsorption speed and a high adsorption capacity of PAC. The adsorption process was exothermic and conformed to the Freundlich models. The adsorption kinetics fitted better to the pseudo-second-order model. These results show that CGTR can be used as a potential adsorbent of phenols in wastewater.

Hydrothermal alkali metal catalyst recovery process

DOEpatents

Eakman, James M.; Clavenna, LeRoy R.

1979-01-01

In a coal gasification operation or similar conversion process carried out in the presence of an alkali metal-containing catalyst wherein solid particles containing alkali metal residues are produced, alkali metal constituents are recovered from the particles primarily in the form of water soluble alkali metal formates by treating the particles with a calcium or magnesium-containing compound in the presence of water at a temperature between about 250.degree. F. and about 700.degree. F. and in the presence of added carbon monoxide. During the treating process the water insoluble alkali metal compounds comprising the insoluble alkali metal residues are converted into water soluble alkali metal formates. The resultant aqueous solution containing water soluble alkali metal formates is then separated from the treated particles and any insoluble materials formed during the treatment process, and recycled to the gasification process where the alkali metal formates serve as at least a portion of the alkali metal constituents which comprise the alkali metal-containing catalyst. This process permits increased recovery of alkali metal constituents, thereby decreasing the overall cost of the gasification process by reducing the amount of makeup alkali metal compounds necessary.

Production of hydrogen driven from biomass waste to power Remote areas away from the electric grid utilizing fuel cells and internal combustion engines vehicles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tawfik, Hazem

Recent concerns over the security and reliability of the world’s energy supply has caused a flux towards the research and development of renewable sources. A leading renewable source has been found in the biomass gasification of biological materials derived from organic matters such as wood chips, forest debris, and farm waste that are found in abundance in the USA. Accordingly, there is a very strong interest worldwide in the development of new technologies that provide an in-depth understanding of this economically viable energy source. This work aims to allow the coupling of biomass gasification and fuel cell systems as wellmore » as Internal Combustion Engines (ICE) to produce high-energy efficiency, clean environmental performance and near-zero greenhouse gas emissions. Biomass gasification is a process, which produces synthesis gas (syngas) that contains 19% hydrogen and 20% carbon monoxide from inexpensive organic matter waste. This project main goal is to provide cost effective energy to the public utilizing remote farms’ waste and landfill recycling area.« less

Leaching of major and trace elements from paper-plastic gasification chars: an experimental and modelling study.

PubMed

Fuente-Cuesta, A; Lopez-Anton, M A; Diaz-Somoano, M; Zomeren, A van; Cieplik, M; Martínez-Tarazona, M R

2013-01-15

The control of soluble metal species in the sub-product leachate generated in electricity production processes is of great concern from an environmental and health point of view. Unlike fly ash, the leaching behaviour of char materials has received little attention. Yet, these solids are captured together with fly ashes in the particle control devices of power plants and are emitted in the same way as by-products. The present study was carried out using two char samples: (i) a raw char and (ii) the same type of char employed in a previous study so that it could serve as a sorbent for mercury species in gas phase. The char samples were by-products (residues) that had been generated during the gasification of plastic and paper waste. The leachates were analyzed for the following elements: Al, Ca, Si, Mg, Ba, Cu, Ni, Pb, Zn, Mo and Hg. In addition, geochemical modelling of the leaching test results was employed to identify the underlying chemical processes that led to the release of toxic elements. The results showed that at alkaline pH values, sorption on the solid surfaces of the char was negligible due to the inorganic complexation of cations in the solution. When the char was used as mercury sorbent slight changes occurred on the reactive surface resulting in the modification of the binding of some elements. As the pH increased, complexation with dissolved organic matter played a more important role in the case of some elements such as Cu because of the greater concentration of dissolved organic matter in solution. Copyright © 2012 Elsevier B.V. All rights reserved.

77 FR 59166 - South Mississippi Electric Cooperative: Plant Ratcliffe, Kemper County Integrated Gasification...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-26

... Ratcliffe, Kemper County Integrated Gasification Combined-Cycle (IGCC) Project AGENCY: Rural Utilities... Plant Ratcliffe, an Integrated Gasification Combined-Cycle Facility located in Kemper County... Company (MPCo), and will demonstrate the feasibility of the Integrated Gasification Combined-Cycle (IGCC...

Energy from gasification of solid wastes.

PubMed

Belgiorno, V; De Feo, G; Della Rocca, C; Napoli, R M A

2003-01-01

Gasification technology is by no means new: in the 1850s, most of the city of London was illuminated by "town gas" produced from the gasification of coal. Nowadays, gasification is the main technology for biomass conversion to energy and an attractive alternative for the thermal treatment of solid waste. The number of different uses of gas shows the flexibility of gasification and therefore allows it to be integrated with several industrial processes, as well as power generation systems. The use of a waste-biomass energy production system in a rural community is very interesting too. This paper describes the current state of gasification technology, energy recovery systems, pre-treatments and prospective in syngas use with particular attention to the different process cycles and environmental impacts of solid wastes gasification.

Waste-to-Energy Plant Environmental Assessment, Dyess Air Force Base, Texas

DTIC Science & Technology

2011-09-01

pyrolysis can be defined as “ gasification minus oxygen.” Pyrolysis is the technique of heating organic matter ( biomass ) between 480 and 1,470 °F in the...provider using one of four alternative technologies: 1) gasification ; 2) pyrolysis; 3) plasma gasification /pyrolysis and 4) incineration. Under this...the solicitation to build a WTE plant based on one of the following alternative technologies: I) gasification ; 2) pyrolysis; 3) plasma gasification

Hydrothermal carbonization of animal manures: Processes and energetics

USDA-ARS?s Scientific Manuscript database

Hydrothermal carbonization (HTC) is an emerging technology for thermochemically converting biomass and waste materials into value-added carbonaceous char called hydrochar. HTC is well suited to manage wet feedstocks streams because pre-drying prior to processing is not required as with gasification...

Jesse E. Hensley | NREL

Science.gov Websites

biomass Low temperature hydrodeoxygenation Advanced equipment and laboratory design Membrane separations Production of Premium Fuels and Chemicals from Gasified Biomass Plant materials contain complex chemical conversion facility and the energy costs associated with gasification (studied in detail by our Analysis team

40 CFR 60.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the purpose of providing steam to a steam-electric generator that would produce electrical energy for... divided solid or liquid material, other than uncombined water, as measured by the reference methods..., magnetohydrodynamics, direct and indirect coal-fired turbines, integrated gasification fuel cells, or as determined by...

40 CFR 60.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the purpose of providing steam to a steam-electric generator that would produce electrical energy for... divided solid or liquid material, other than uncombined water, as measured by the reference methods..., magnetohydrodynamics, direct and indirect coal-fired turbines, integrated gasification fuel cells, or as determined by...

40 CFR 60.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the purpose of providing steam to a steam-electric generator that would produce electrical energy for... divided solid or liquid material, other than uncombined water, as measured by the reference methods..., magnetohydrodynamics, direct and indirect coal-fired turbines, integrated gasification fuel cells, or as determined by...

Interaction and its induced inhibiting or synergistic effects during co-gasification of coal char and biomass char.

PubMed

Ding, Liang; Zhang, Yongqi; Wang, Zhiqing; Huang, Jiejie; Fang, Yitian

2014-12-01

Co-gasification of coal char and biomass char was conducted to investigate the interactions between them. And random pore model (RPM) and modified random pore model (MRPM) were applied to describe the gasification behaviors of the samples. The results show that inhibiting effect was observed during co-gasification of corn stalk char with Hulunbeier lignite coal char, while synergistic effects were observed during co-gasification of corn stalk char with Shenmu bituminous coal char and Jincheng anthracite coal char. The inhibiting effect was attributed to the intimate contact and comparable gasification rate between biomass char and coal char, and the loss of the active form of potassium caused by the formation of KAlSiO4, which was proved to be inactive during gasification. While the synergistic effect was caused by the high potassium content of biomass char and the significant difference of reaction rate between coal char and biomass char during gasification. Copyright © 2014 Elsevier Ltd. All rights reserved.

Integrated bioenergy conversion concepts for small scale gasification power systems

NASA Astrophysics Data System (ADS)

Aldas, Rizaldo Elauria

Thermal and biological gasification are promising technologies for addressing the emerging concerns in biomass-based renewable energy, environmental protection and waste management. However, technical barriers such as feedstock quality limitations, tars, and high NOx emissions from biogas fueled engines impact their full utilization and make them suffer at the small scale from the need to purify the raw gas for most downstream processes, including power generation other than direct boiler use. The two separate gasification technologies may be integrated to better address the issues of power generation and waste management and to complement some of each technologies' limitations. This research project investigated the technical feasibility of an integrated thermal and biological gasification concept for parameters critical to appropriately matching an anaerobic digester with a biomass gasifier. Specific studies investigated the thermal gasification characteristics of selected feedstocks in four fixed-bed gasification experiments: (1) updraft gasification of rice hull, (2) indirect-heated gasification of rice hull, (3) updraft gasification of Athel wood, and (4) downdraft gasification of Athel and Eucalyptus woods. The effects of tars and other components of producer gas on anaerobic digestion at mesophilic temperature of 36°C and the biodegradation potentials and soil carbon mineralization of gasification tars during short-term aerobic incubation at 27.5°C were also examined. Experiments brought out the ranges in performance and quality and quantity of gasification products under different operating conditions and showed that within the conditions considered in the study, these gasification products did not adversely impact the overall digester performance. Short-term aerobic incubation demonstrated variable impacts on carbon mineralization depending on tar and soil conditions. Although tars exhibited low biodegradation indices, degradation may be improved if the microorganisms used to deal with tars are selected and pre-conditioned to the tar environment. Overall, the results provided a basis for operational and design strategy for a combined gasification system but further study is recommended such as determination of the impacts in terms of emissions, power, efficiency and costs associated with the use of producer gas-enriched biogas taking advantage of hydrogen enrichment to reduce NOx and other pollutants in reciprocating engines and other energy conversion systems.

Physical and chemical characterization of waste wood derived biochars.

PubMed

Yargicoglu, Erin N; Sadasivam, Bala Yamini; Reddy, Krishna R; Spokas, Kurt

2015-02-01

Biochar, a solid byproduct generated during waste biomass pyrolysis or gasification in the absence (or near-absence) of oxygen, has recently garnered interest for both agricultural and environmental management purposes owing to its unique physicochemical properties. Favorable properties of biochar include its high surface area and porosity, and ability to adsorb a variety of compounds, including nutrients, organic contaminants, and some gases. Physical and chemical properties of biochars are dictated by the feedstock and production processes (pyrolysis or gasification temperature, conversion technology and pre- and post-treatment processes, if any), which vary widely across commercially produced biochars. In this study, several commercially available biochars derived from waste wood are characterized for physical and chemical properties that can signify their relevant environmental applications. Parameters characterized include: physical properties (particle size distribution, specific gravity, density, porosity, surface area), hydraulic properties (hydraulic conductivity and water holding capacity), and chemical and electrochemical properties (organic matter and organic carbon contents, pH, oxidation-reduction potential and electrical conductivity, zeta potential, carbon, nitrogen and hydrogen (CHN) elemental composition, polycyclic aromatic hydrocarbons (PAHs), heavy metals, and leachable PAHs and heavy metals). A wide range of fixed carbon (0-47.8%), volatile matter (28-74.1%), and ash contents (1.5-65.7%) were observed among tested biochars. A high variability in surface area (0.1-155.1g/m(2)) and PAH and heavy metal contents of the solid phase among commercially available biochars was also observed (0.7-83 mg kg(-1)), underscoring the importance of pre-screening biochars prior to application. Production conditions appear to dictate PAH content--with the highest PAHs observed in biochar produced via fast pyrolysis and lowest among the gasification-produced biochars. Copyright © 2014 Elsevier Ltd. All rights reserved.

Bed Agglomeration During the Steam Gasification of a High Lignin Corn Stover Simultaneous Saccharification and Fermentation (SSF) Digester Residue

DOE Office of Scientific and Technical Information (OSTI.GOV)

Howe, Daniel T.; Taasevigen, Danny J.; Gerber, Mark A.

This research investigates the bed agglomeration phenomena during the steam gasification of a high lignin residue produced from the simultaneous saccharification and fermentation (SSF) of corn stover in a bubbling fluidized bed. The studies were conducted at 895°C using alumina as bed material. Biomass was fed at 1.5 kg/hr, while steam was fed to give a velocity equal to 2.5 times the minimum fluidization velocity, with a steam/carbon ratio of 0.9. The pelletized feedstock was co-fed with a cooling nitrogen stream to mitigate feed line plugging issues. Tar production was high at 50.3 g/Nm3, and the fraction of C10+ compoundsmore » was greater than that seen in the gasification of traditional lignocellulosic feedstocks. Carbon closures over 94 % were achieved for all experiments. Bed agglomeration was found to be problematic, indicated by pressure drop increases observed below the bed and upstream of the feed line. Two size categories of solids were recovered from the reactor, +60 mesh and -60 mesh. After a 2.75-hour experiment, 61.7 wt % was recovered as -60 mesh particles and 38.2 wt% of the recovered reactor solids were +60 mesh. A sizeable percentage, 31.8 wt%, was +20 mesh. The -60 mesh particles were mainly formed by the initial bed material (Al2O3). Almost 50 wt. % of the + 20 mesh particles was found to be formed by organics. The unreacted carbon remaining in the reactor resulted in a low conversion rate to product gas. ICP-AES, SEM, SEM-EDS, and XRD confirmed that the large agglomerates (+ 20 mesh) were not encapsulated bed material but rather un-gasified feedstock pellets with sand particles attached to it.« less

Experimental study on air-stream gasification of biomass micron fuel (BMF) in a cyclone gasifier.

PubMed

Guo, X J; Xiao, B; Zhang, X L; Luo, S Y; He, M Y

2009-01-01

Based on biomass micron fuel (BMF) with particle size of less than 250 microm, a cyclone gasifier concept has been considered in our laboratory for biomass gasification. The concept combines and integrates partial oxidation, fast pyrolysis, gasification, and tar cracking, as well as a shift reaction, with the purpose of producing a high quality of gas. In this paper, experiments of BMF air-stream gasification were carried out by the gasifier, with energy for BMF gasification produced by partial combustion of BMF within the gasifier using a hypostoichiometric amount of air. The effects of ER (0.22-0.37) and S/B (0.15-0.59) and biomass particle size on the performances of BMF gasification and the gasification temperature were studied. Under the experimental conditions, the temperature, gas yields, LHV of the gas fuel, carbon conversion efficiency, stream decomposition and gasification efficiency varied in the range of 586-845 degrees C, 1.42-2.21 N m(3)/kg biomass, 3806-4921 kJ/m(3), 54.44%-85.45%, 37.98%-70.72%, and 36.35%-56.55%, respectively. The experimental results showed that the gasification performance was best with ER being 3.7 and S/B being 0.31 and smaller particle, as well as H(2)-content. And the BMF gasification by air and low temperature stream in the cyclone gasifier with the energy self-sufficiency is reliable.

Density functional theory study the effects of oxygen-containing functional groups on oxygen molecules and oxygen atoms adsorbed on carbonaceous materials.

PubMed

Qi, Xuejun; Song, Wenwu; Shi, Jianwei

2017-01-01

Density functional theory was used to study the effects of different types of oxygen-containing functional groups on the adsorption of oxygen molecules and single active oxygen atoms on carbonaceous materials. During gasification or combustion reactions of carbonaceous materials, oxygen-containing functional groups such as hydroxyl(-OH), carbonyl(-CO), quinone(-O), and carboxyl(-COOH) are often present on the edge of graphite and can affect graphite's chemical properties. When oxygen-containing functional groups appear on a graphite surface, the oxygen molecules are strongly adsorbed onto the surface to form a four-member ring structure. At the same time, the O-O bond is greatly weakened and easily broken. The adsorption energy value indicates that the adsorption of oxygen molecules changes from physisorption to chemisorption for oxygen-containing functional groups on the edge of a graphite surface. In addition, our results indicate that the adsorption energy depends on the type of oxygen-containing functional group. When a single active oxygen atom is adsorbed on the bridge site of graphite, it gives rise to a stable epoxy structure. Epoxy can cause deformation of the graphite lattice due to the transition of graphite from sp2 to sp3 after the addition of an oxygen atom. For quinone group on the edge of graphite, oxygen atoms react with carbon atoms to form the precursor of CO2. Similarly, the single active oxygen atoms of carbonyl groups can interact with edge carbon atoms to form the precursor of CO2. The results show that oxygen-containing functional groups on graphite surfaces enhance the activity of graphite, which promotes adsorption on the graphite surface.

Density functional theory study the effects of oxygen-containing functional groups on oxygen molecules and oxygen atoms adsorbed on carbonaceous materials

PubMed Central

Song, Wenwu; Shi, Jianwei

2017-01-01

Density functional theory was used to study the effects of different types of oxygen-containing functional groups on the adsorption of oxygen molecules and single active oxygen atoms on carbonaceous materials. During gasification or combustion reactions of carbonaceous materials, oxygen-containing functional groups such as hydroxyl(-OH), carbonyl(-CO), quinone(-O), and carboxyl(-COOH) are often present on the edge of graphite and can affect graphite’s chemical properties. When oxygen-containing functional groups appear on a graphite surface, the oxygen molecules are strongly adsorbed onto the surface to form a four-member ring structure. At the same time, the O-O bond is greatly weakened and easily broken. The adsorption energy value indicates that the adsorption of oxygen molecules changes from physisorption to chemisorption for oxygen-containing functional groups on the edge of a graphite surface. In addition, our results indicate that the adsorption energy depends on the type of oxygen-containing functional group. When a single active oxygen atom is adsorbed on the bridge site of graphite, it gives rise to a stable epoxy structure. Epoxy can cause deformation of the graphite lattice due to the transition of graphite from sp2 to sp3 after the addition of an oxygen atom. For quinone group on the edge of graphite, oxygen atoms react with carbon atoms to form the precursor of CO2. Similarly, the single active oxygen atoms of carbonyl groups can interact with edge carbon atoms to form the precursor of CO2. The results show that oxygen-containing functional groups on graphite surfaces enhance the activity of graphite, which promotes adsorption on the graphite surface. PMID:28301544

Physical and chemical characterization of waste wood derived biochars

USDA-ARS?s Scientific Manuscript database

Biochar, a solid byproduct generated during waste biomass pyrolysis or gasification in the absence (or near-absence) of oxygen, has recently garnered interest for both agricultural and environmental management purposes owing to its unique physicochemical properties, such as its high surface area and...

Contributions of pyrogenic materials on the accumulation of soil organic matter

USDA-ARS?s Scientific Manuscript database

Soil amendment of charcoal co-product (HHVdb as high as coal) from thermochemical waste biomass-to-energy conversion (slow/fast pyrolysis and gasification) has received considerable interests for both contaminated and agricultural lands. Biochar amendment not only increases soil organic carbon cont...

Dielectric properties of biomass and biochar mixtures for bioenergy applications

USDA-ARS?s Scientific Manuscript database

Biomass is an abundant and renewable energy resource, which may be converted into energy-dense products through thermochemical processes such as pyrolysis and gasification. Since microwave heating depends on the dielectric properties of the biomass material, these properties were measured at freque...

Baltimore applications project

NASA Technical Reports Server (NTRS)

Golden, T. S.; Yaffee, P.

1979-01-01

An update is presented for the following projects: (1) asphalt pavement recycling; (2) data collection platform/water quality monitoring; (3) digital emergency traffic routing; (4) fire department communications and dispatch system; (5) health department management information system; (6) hazardous materials; (7) coal gasification; and (8) emergency vehicle proximity sensing.

Producing fired bricks using coal slag from a gasification plant in indiana

USGS Publications Warehouse

Chen, L.-M.; Chou, I.-Ming; Chou, S.-F.J.; Stucki, J.W.

2009-01-01

Integrated gasification combined cycle (IGCC) is a promising power generation technology which increases the efficiency of coal-to-power conversion and enhances carbon dioxide concentration in exhaust emissions for better greenhouse gas capture. Two major byproducts from IGCC plants are bottom slag and sulfur. The sulfur can be processed into commercially viable products, but high value applications need to be developed for the slag material in order to improve economics of the process. The purpose of this study was to evaluate the technical feasibility of incorporating coal slag generated by the Wabash River IGCC plant in Indiana as a raw material for the production of fired bricks. Full-size bricks containing up to 20 wt% of the coal slag were successfully produced at a bench-scale facility. These bricks have color and texture similar to those of regular fired bricks and their water absorption properties met the ASTM specifications for a severe weathering grade. Other engineering properties tests, including compressive strength tests, are in progress.

Dual path mechanism in the thermal reduction of graphene oxide.

PubMed

Larciprete, Rosanna; Fabris, Stefano; Sun, Tao; Lacovig, Paolo; Baraldi, Alessandro; Lizzit, Silvano

2011-11-02

Graphene is easily produced by thermally reducing graphene oxide. However, defect formation in the C network during deoxygenation compromises the charge carrier mobility in the reduced material. Understanding the mechanisms of the thermal reactions is essential for defining alternative routes able to limit the density of defects generated by carbon evolution. Here, we identify a dual path mechanism in the thermal reduction of graphene oxide driven by the oxygen coverage: at low surface density, the O atoms adsorbed as epoxy groups evolve as O(2) leaving the C network unmodified. At higher coverage, the formation of other O-containing species opens competing reaction channels, which consume the C backbone. We combined spectroscopic tools and ab initio calculations to probe the species residing on the surface and those released in the gas phase during heating and to identify reaction pathways and rate-limiting steps. Our results illuminate the current puzzling scenario of the low temperature gasification of graphene oxide.

Method for gasification of deep, thin coal seams. [DOE patent

DOEpatents

Gregg, D.W.

1980-08-29

A method of gasification of coal in deep, thin seams by using controlled bending subsidence to confine gas flow to a region close to the unconsumed coal face is given. The injection point is moved sequentially around the perimeter of a coal removal area from a production well to sweep out the area to cause the controlled bending subsidence. The injection holes are drilled vertically into the coal seam through the overburden or horizontally into the seam from an exposed coal face. The method is particularly applicable to deep, thin seams found in the eastern United States and at abandoned strip mines where thin seams were surface mined into a hillside or down a modest dip until the overburden became too thick for further mining.

Method for gasification of deep, thin coal seams

DOEpatents

Gregg, David W.

1982-01-01

A method of gasification of coal in deep, thin seams by using controlled bending subsidence to confine gas flow to a region close to the unconsumed coal face. The injection point is moved sequentially around the perimeter of a coal removal area from a production well to sweep out the area to cause the controlled bending subsidence. The injection holes are drilled vertically into the coal seam through the overburden or horizontally into the seam from an exposed coal face. The method is particularly applicable to deep, thin seams found in the eastern United States and at abandoned strip mines where thin seams were surface mined into a hillside or down a modest dip until the overburden became too thick for further mining.

Post-harvest processing methods for reduction of silica and alkali metals in wheat straw.

PubMed

Thompson, David N; Shaw, Peter G; Lacey, Jeffrey A

2003-01-01

Silica and alkali metals in wheat straw limit its use for bioenergy and gasification. Slag deposits occur via the eutectic melting of SiO2 with K2O, trapping chlorides at surfaces and causing corrosion. A minimum melting point of 950 degrees C is desirable, corresponding to an SiO2:K2O weight ratio of about 3:1. Mild chemical treatments were used to reduce Si, K, and Cl, while varying temperature, concentration, % solids, and time. Dilute acid was more effective at removing K and Cl, while dilute alkali was more effective for Si. Reduction of minerals in this manner may prove economical for increasing utilization of the straw for combustion or gasification.

LCA of management strategies for RDF incineration and gasification bottom ash based on experimental leaching data.

PubMed

Di Gianfilippo, Martina; Costa, Giulia; Pantini, Sara; Allegrini, Elisa; Lombardi, Francesco; Astrup, Thomas Fruergaard

2016-01-01

The main characteristics and environmental properties of the bottom ash (BA) generated from thermal treatment of waste may vary significantly depending on the type of waste and thermal technology employed. Thus, to ensure that the strategies selected for the management of these residues do not cause adverse environmental impacts, the specific properties of BA, in particular its leaching behavior, should be taken into account. This study focuses on the evaluation of potential environmental impacts associated with two different management options for BA from thermal treatment of Refuse Derived Fuel (RDF): landfilling and recycling as a filler for road sub bases. Two types of thermal treatment were considered: incineration and gasification. Potential environmental impacts were evaluated by life-cycle assessment (LCA) using the EASETECH model. Both non-toxicity related impact categories (i.e. global warming and mineral abiotic resource depletion) and toxic impact categories (i.e. human toxicity and ecotoxicity) were assessed. The system boundaries included BA transport from the incineration/gasification plants to the landfills and road construction sites, leaching of potentially toxic metals from the BA, the avoided extraction, crushing, transport and leaching of virgin raw materials for the road scenarios, and material and energy consumption for the construction of the landfills. To provide a quantitative assessment of the leaching properties of the two types of BA, experimental leaching data were used to estimate the potential release from each of the two types of residues. Specific attention was placed on the sensitivity of leaching properties and the determination of emissions by leaching, including: leaching data selection, material properties and assumptions related to emission modeling. The LCA results showed that for both types of BA, landfilling was associated with the highest environmental impacts in the non-toxicity related categories. For the toxicity related categories, the two types of residues behaved differently. For incineration BA the contribution of metal leaching to the total impacts had a dominant role, with the highest environmental loads resulting for the road scenario. For the gasification BA, the opposite result was obtained, due to the lower release of contaminants observed for this material compared to incineration BA. Based on the results of this study, it may be concluded that, depending on the type of BA considered, its leaching behavior may significantly affect the results of a LCA regarding its management strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of solid oxide fuel cell systems for electricity generation

NASA Technical Reports Server (NTRS)

Somers, E. V.; Vidt, E. J.; Grimble, R. E.

1982-01-01

Air blown (low BTU) gasification with atmospheric pressure Solid Electrolyte Fuel Cells (SOFC) and Rankine bottoming cycle, oxygen blown (medium BTU) gasification with atmospheric pressure SOFC and Rankine bottoming cycle, air blown gasification with pressurized SOFC and combined Brayton/Rankine bottoming cycle, oxygen blown gasification with pressurized SOFC and combined Brayton/Rankine bottoming cycle were evaluated.

Construction material properties of slag from the high temperature arc gasification of municipal solid waste.

PubMed

Roessler, Justin G; Olivera, Fernando D; Wasman, Scott J; Townsend, Timothy G; McVay, Michael C; Ferraro, Christopher C; Blaisi, Nawaf I

2016-06-01

Slag from the high temperature arc gasification (HTAG) of municipal solid waste (MSW) was tested to evaluate its material properties with respect to use as a construction aggregate. These data were compared to previously compiled values for waste to energy bottom ash, the most commonly produced and beneficially used thermal treatment residue. The slag was tested using gradations representative of a base course and a course aggregate. Los Angeles (LA) abrasion testing demonstrated that the HTAG slag had a high resistance to fracture with a measured LA loss of 24%. Soundness testing indicated a low potential for reactivity and good weathering resistance with a mean soundness loss of 3.14%. The modified Proctor compaction testing found the slag to possess a maximum dry density (24.04kN/m(3)) greater than conventionally used aggregates and WTE BA. The LBR tests demonstrated a substantial bearing capacity (>200). Mineralogical analysis of the HTAG suggested the potential for self cementing character which supports the elevated LBR results. Preliminary material characterization of the HTAG slag establishes potential for beneficial use; larger and longer term studies focusing on the material's possibility for swelling and performance at the field scale level are needed. Copyright © 2016 Elsevier Ltd. All rights reserved.

High temperature gasification of high heating-rate chars using a flat-flame reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Tian; Niu, Yanqing; Wang, Liang

The increasing interest in gasification and oxy-fuel combustion of biomass has heightened the need for a detailed understanding of char gasification in industrially relevant environments (i.e., high temperature and high-heating rate). Despite innumerable studies previously conducted on gasification of biomass, very few have focused on such conditions. Consequently, in this study the high-temperature gasification behaviors of biomass-derived chars were investigated using non-intrusive techniques. Two biomass chars produced at a heating rate of approximately 10 4 K/s were subjected to two gasification environments and one oxidation environment in an entrained flow reactor equipped with an optical particle-sizing pyrometer. A coal charmore » produced from a common U.S. low sulfur subbituminous coal was also studied for comparison. Both char and surrounding gas temperatures were precisely measured along the centerline of the furnace. Despite differences in the physical and chemical properties of the biomass chars, they exhibited rather similar reaction temperatures under all investigated conditions. On the other hand, a slightly lower particle temperature was observed in the case of coal char gasification, suggesting a higher gasification reactivity for the coal char. A comprehensive numerical model was applied to aid the understanding of the conversion of the investigated chars under gasification atmospheres. In addition, a sensitivity analysis was performed on the influence of four parameters (gas temperature, char diameter, char density, and steam concentration) on the carbon conversion rate. Here, the results demonstrate that the gas temperature is the most important single variable influencing the gasification rate.« less

Modeling and comparative assessment of municipal solid waste gasification for energy production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arafat, Hassan A., E-mail: harafat@masdar.ac.ae; Jijakli, Kenan

Highlights: • Study developed a methodology for the evaluation of gasification for MSW treatment. • Study was conducted comparatively for USA, UAE, and Thailand. • Study applies a thermodynamic model (Gibbs free energy minimization) using the Gasify software. • The energy efficiency of the process and the compatibility with different waste streams was studied. - Abstract: Gasification is the thermochemical conversion of organic feedstocks mainly into combustible syngas (CO and H{sub 2}) along with other constituents. It has been widely used to convert coal into gaseous energy carriers but only has been recently looked at as a process for producingmore » energy from biomass. This study explores the potential of gasification for energy production and treatment of municipal solid waste (MSW). It relies on adapting the theory governing the chemistry and kinetics of the gasification process to the use of MSW as a feedstock to the process. It also relies on an equilibrium kinetics and thermodynamics solver tool (Gasify®) in the process of modeling gasification of MSW. The effect of process temperature variation on gasifying MSW was explored and the results were compared to incineration as an alternative to gasification of MSW. Also, the assessment was performed comparatively for gasification of MSW in the United Arab Emirates, USA, and Thailand, presenting a spectrum of socioeconomic settings with varying MSW compositions in order to explore the effect of MSW composition variance on the products of gasification. All in all, this study provides an insight into the potential of gasification for the treatment of MSW and as a waste to energy alternative to incineration.« less

High temperature gasification of high heating-rate chars using a flat-flame reactor

DOE PAGES

Li, Tian; Niu, Yanqing; Wang, Liang; ...

2017-08-25

The increasing interest in gasification and oxy-fuel combustion of biomass has heightened the need for a detailed understanding of char gasification in industrially relevant environments (i.e., high temperature and high-heating rate). Despite innumerable studies previously conducted on gasification of biomass, very few have focused on such conditions. Consequently, in this study the high-temperature gasification behaviors of biomass-derived chars were investigated using non-intrusive techniques. Two biomass chars produced at a heating rate of approximately 10 4 K/s were subjected to two gasification environments and one oxidation environment in an entrained flow reactor equipped with an optical particle-sizing pyrometer. A coal charmore » produced from a common U.S. low sulfur subbituminous coal was also studied for comparison. Both char and surrounding gas temperatures were precisely measured along the centerline of the furnace. Despite differences in the physical and chemical properties of the biomass chars, they exhibited rather similar reaction temperatures under all investigated conditions. On the other hand, a slightly lower particle temperature was observed in the case of coal char gasification, suggesting a higher gasification reactivity for the coal char. A comprehensive numerical model was applied to aid the understanding of the conversion of the investigated chars under gasification atmospheres. In addition, a sensitivity analysis was performed on the influence of four parameters (gas temperature, char diameter, char density, and steam concentration) on the carbon conversion rate. Here, the results demonstrate that the gas temperature is the most important single variable influencing the gasification rate.« less

Advanced geophysical underground coal gasification monitoring

DOE PAGES

Mellors, Robert; Yang, X.; White, J. A.; ...

2014-07-01

Underground Coal Gasification (UCG) produces less surface impact, atmospheric pollutants and greenhouse gas than traditional surface mining and combustion. Therefore, it may be useful in mitigating global change caused by anthropogenic activities. Careful monitoring of the UCG process is essential in minimizing environmental impact. Here we first summarize monitoring methods that have been used in previous UCG field trials. We then discuss in more detail a number of promising advanced geophysical techniques. These methods – seismic, electromagnetic, and remote sensing techniques – may provide improved and cost-effective ways to image both the subsurface cavity growth and surface subsidence effects. Activemore » and passive seismic data have the promise to monitor the burn front, cavity growth, and observe cavity collapse events. Electrical resistance tomography (ERT) produces near real time tomographic images autonomously, monitors the burn front and images the cavity using low-cost sensors, typically running within boreholes. Interferometric synthetic aperture radar (InSAR) is a remote sensing technique that has the capability to monitor surface subsidence over the wide area of a commercial-scale UCG operation at a low cost. It may be possible to infer cavity geometry from InSAR (or other surface topography) data using geomechanical modeling. The expected signals from these monitoring methods are described along with interpretive modeling for typical UCG cavities. They are illustrated using field results from UCG trials and other relevant subsurface operations.« less

Allothermal steam gasification of biomass in cyclic multi-compartment bubbling fluidized-bed gasifier/combustor - new reactor concept.

PubMed

Iliuta, Ion; Leclerc, Arnaud; Larachi, Faïçal

2010-05-01

A new reactor concept of allothermal cyclic multi-compartment fluidized bed steam biomass gasification is proposed and analyzed numerically. The concept combines space and time delocalization to approach an ideal allothermal gasifier. Thermochemical conversion of biomass in periodic time and space sequences of steam biomass gasification and char/biomass combustion is simulated in which the exothermic combustion compartments provide heat into an array of interspersed endothermic steam gasification compartments. This should enhance unit heat integration and thermal efficiency and procure N(2)-free biosyngas with recourse neither to oxygen addition in steam gasification nor contact between flue and syngas. The dynamic, one-dimensional, multi-component, non-isothermal model developed for this concept accounts for detailed solid and gas flow dynamics whereupon gasification/combustion reaction kinetics, thermal effects and freeboard-zone reactions were tied. Simulations suggest that allothermal operation could be achieved with switch periods in the range of a minute supporting practical feasibility for portable small-scale gasification units. Copyright 2009 Elsevier Ltd. All rights reserved.

Two-step gasification of cattle manure for hydrogen-rich gas production: Effect of biochar preparation temperature and gasification temperature.

PubMed

Xin, Ya; Cao, Hongliang; Yuan, Qiaoxia; Wang, Dianlong

2017-10-01

Two-step gasification process was proposed to dispose cattle manure for hydrogen rich gas production. The effect of temperature on product distribution and biochar properties were first studied in the pyrolysis-carbonization process. The steam gasification of biochar derived from different pyrolysis-carbonization temperatures was then performed at 750°C and 850°C. The biochar from the pyrolysis-carbonization temperatures of 500°C had high carbon content and low volatiles content. According to the results of gasification stage, the pyrolysis-carbonization temperature of 500°C and the gasification temperature of 850°C were identified as the suitable conditions for hydrogen production. We obtained 1.61m 3 /kg of syngas production, 0.93m 3 /kg of hydrogen yield and 57.58% of hydrogen concentration. This study shows that two-step gasification is an efficient waste-to-hydrogen energy process. Copyright © 2017 Elsevier Ltd. All rights reserved.

Survey study of the efficiency and economics of hydrogen liquefaction

NASA Technical Reports Server (NTRS)

1975-01-01

The production of liquid hydrogen, with coal as the starting material, is reported. The minimum practicable energy and cost for liquefaction of gaseous hydrogen in the 1985-2000 time period is presented to investigate the possible benefits of the integration of coal gasification processes with the liquefaction process.

NANOCRYSTALLINE MATERIALS FOR REMOVAL OF REDUCED SULFUR AND NITROGEN COMPOUNDS FROM FUEL GAS - PHASE II

EPA Science Inventory

Integrated gasification combined cycle (IGCC), which uses a gasilier to convert coal to fuel gas, and then uses a combined cycle power block to generate electricity. is one of the most promising technologies for generating electricity from coal in an environmentally sustainabl...

Hydrogen production from carbonaceous material

DOEpatents

Lackner, Klaus S.; Ziock, Hans J.; Harrison, Douglas P.

2004-09-14

Hydrogen is produced from solid or liquid carbon-containing fuels in a two-step process. The fuel is gasified with hydrogen in a hydrogenation reaction to produce a methane-rich gaseous reaction product, which is then reacted with water and calcium oxide in a hydrogen production and carbonation reaction to produce hydrogen and calcium carbonate. The calcium carbonate may be continuously removed from the hydrogen production and carbonation reaction zone and calcined to regenerate calcium oxide, which may be reintroduced into the hydrogen production and carbonation reaction zone. Hydrogen produced in the hydrogen production and carbonation reaction is more than sufficient both to provide the energy necessary for the calcination reaction and also to sustain the hydrogenation of the coal in the gasification reaction. The excess hydrogen is available for energy production or other purposes. Substantially all of the carbon introduced as fuel ultimately emerges from the invention process in a stream of substantially pure carbon dioxide. The water necessary for the hydrogen production and carbonation reaction may be introduced into both the gasification and hydrogen production and carbonation reactions, and allocated so as transfer the exothermic heat of reaction of the gasification reaction to the endothermic hydrogen production and carbonation reaction.

A study of industrial hydrogen and syngas supply systems

NASA Technical Reports Server (NTRS)

Amos, W. J.; Solomon, J.; Eliezer, K. F.

1979-01-01

The potential and incentives required for supplying hydrogen and syngas feedstocks to the U.S. chemical industry from coal gasification systems were evaluated. Future hydrogen and syngas demand for chemical manufacture was estimated by geographic area and projected economics for hydrogen and syngas manufacture was estimated with geographic area of manufacture and plant size as parameters. Natural gas, oil and coal feedstocks were considered. Problem areas presently affecting the commercial feasibility of coal gasification discussed include the impact of potential process improvements, factors involved in financing coal gasification plants, regulatory barriers affecting coal gasification, coal mining/transportation, air quality regulations, and competitive feedstock pricing barriers. The potential for making coal gasification the least costly H2 and syngas supply option. Options to stimulate coal gasification system development are discussed.

Product Chemistry and Process Efficiency of Biomass Torrefaction, Pyrolysis and Gasification Studied by High-Throughput Techniques and Multivariate Analysis

NASA Astrophysics Data System (ADS)

Xiao, Li

Despite the great passion and endless efforts on development of renewable energy from biomass, the commercialization and scale up of biofuel production is still under pressure and facing challenges. New ideas and facilities are being tested around the world targeting at reducing cost and improving product value. Cutting edge technologies involving analytical chemistry, statistics analysis, industrial engineering, computer simulation, and mathematics modeling, etc. keep integrating modern elements into this classic research. One of those challenges of commercializing biofuel production is the complexity from chemical composition of biomass feedstock and the products. Because of this, feedstock selection and process optimization cannot be conducted efficiently. This dissertation attempts to further evaluate biomass thermal decomposition process using both traditional methods and advanced technique (Pyrolysis Molecular Beam Mass Spectrometry). Focus has been made on data base generation of thermal decomposition products from biomass at different temperatures, finding out the relationship between traditional methods and advanced techniques, evaluating process efficiency and optimizing reaction conditions, comparison of typically utilized biomass feedstock and new search on innovative species for economical viable feedstock preparation concepts, etc. Lab scale quartz tube reactors and 80il stainless steel sample cups coupled with auto-sampling system were utilized to simulate the complicated reactions happened in real fluidized or entrained flow reactors. Two main high throughput analytical techniques used are Near Infrared Spectroscopy (NIR) and Pyrolysis Molecular Beam Mass Spectrometry (Py-MBMS). Mass balance, carbon balance, and product distribution are presented in detail. Variations of thermal decomposition temperature range from 200°C to 950°C. Feedstocks used in the study involve typical hardwood and softwood (red oak, white oak, yellow poplar, loblolly pine), fast growing energy crops (switchgrass), and popular forage crop (alfalfa), as well as biochar derived from those materials and their mixtures. It demonstrated that Py-MBMS coupled with MVA could be used as fast analytical tools for the study of not only biomass composition but also its thermal decomposition behaviors. It found that the impact of biomass composition heavily depends on the thermal decomposition temperature because at different temperature, the composition of biomass decomposed and the impact of minerals on the decomposition reaction varies. At low temperature (200-500°C), organic compounds attribute to the majority of variation in thermal decomposition products. At higher temperature, inorganics dramatically changed the pyrolysis pathway of carbohydrates and possibly lignin. In gasification, gasification tar formation is also observed to be impacted by ash content in vapor and char. In real reactor, biochar structure also has interactions with other fractions to make the final pyrolysis and gasification product. Based on the evaluation of process efficiencies during torrefaction, temperature ranging from 275°C to 300°C with short residence time (<10min) are proposed to be optimal torrefaction conditions. 500°C is preferred to 700°C as primary pyrolysis temperature in two stage gasification because higher primary pyrolysis temperature resulted in more tar and less gasification char. Also, in terms of carbon yield, more carbon is lost in tar while less carbon is retained in gas product using 700°C as primary pyrolysis temperature. In addition, pyrolysis char is found to produce less tar and more gas during steam gasification compared with gasification of pyrolysis vapor. Thus it is suggested that torrefaction might be an efficient pretreatment for biomass gasification because it can largely improve the yield of pyrolysis char during the primary pyrolysis step of gasification thus reduce the total tar of the overall gasification products. Future work is suggested in the end.

High Pressure Biomass Gasification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agrawal, Pradeep K

2016-07-29

According to the Billion Ton Report, the U.S. has a large supply of biomass available that can supplement fossil fuels for producing chemicals and transportation fuels. Agricultural waste, forest residue, and energy crops offer potential benefits: renewable feedstock, zero to low CO 2 emissions depending on the specific source, and domestic supply availability. Biomass can be converted into chemicals and fuels using one of several approaches: (i) biological platform converts corn into ethanol by using depolymerization of cellulose to form sugars followed by fermentation, (ii) low-temperature pyrolysis to obtain bio-oils which must be treated to reduce oxygen content via HDOmore » hydrodeoxygenation), and (iii) high temperature pyrolysis to produce syngas (CO + H 2). This last approach consists of producing syngas using the thermal platform which can be used to produce a variety of chemicals and fuels. The goal of this project was to develop an improved understanding of the gasification of biomass at high pressure conditions and how various gasification parameters might affect the gasification behavior. Since most downstream applications of synags conversion (e.g., alcohol synthesis, Fischer-Tropsch synthesis etc) involve utilizing high pressure catalytic processes, there is an interest in carrying out the biomass gasification at high pressure which can potentially reduce the gasifier size and subsequent downstream cleaning processes. It is traditionally accepted that high pressure should increase the gasification rates (kinetic effect). There is also precedence from coal gasification literature from the 1970s that high pressure gasification would be a beneficial route to consider. Traditional approach of using thermogravimetric analyzer (TGA) or high-pressure themogravimetric analyzer (PTGA) worked well in understanding the gasification kinetics of coal gasification which was useful in designing high pressure coal gasification processes. However, similar approach for biomass gasification was not very useful and was the impetus for this study. Specifically, we aimed this study at three broad objectives: (i) defining operating conditions at which C 2-C 4 hydrocarbons are formed since these represent loss of carbon efficiency, (ii) understanding the formation of tar species which create downstream processing difficulties in addition of carbon efficiency loss, and (iii) kinetics of biomass gasification where it would be possible to understand the effect of operating conditions and gas phase composition.« less

Chars from gasification of coal and pine activated with K2CO3: acetaminophen and caffeine adsorption from aqueous solutions.

PubMed

Galhetas, Margarida; Mestre, Ana S; Pinto, Moisés L; Gulyurtlu, Ibrahim; Lopes, Helena; Carvalho, Ana P

2014-11-01

The high carbon contents and low toxicity levels of chars from coal and pine gasification provide an incentive to consider their use as precursors of porous carbons obtained by chemical activation with K2CO3. Given the chars characteristics, previous demineralization and thermal treatments were made, but no improvement on the solids properties was observed. The highest porosity development was obtained with the biomass derived char (Pi). This char sample produced porous materials with preparation yields near 50% along with high porosity development (ABET≈1500m(2)g(-1)). For calcinations at 800°C, the control of the experimental conditions allowed the preparation of samples with a micropore system formed almost exclusively by larger micropores. A mesopore network was developed only for samples calcined at 900°C. Kinetic and equilibrium acetaminophen and caffeine adsorption data, showed that the processes obey to a pseudo-second order kinetic equation and to the Langmuir model, respectively. The results of sample Pi/1:3/800/2 outperformed those of the commercial carbons. Acetaminophen adsorption process was ruled by the micropore size distribution of the carbons. The caffeine monolayer capacities suggest a very efficient packing of this molecule in samples presenting monomodal micropore size distribution. The surface chemistry seems to be the determinant factor that controls the affinity of caffeine towards the carbons. Copyright © 2014 Elsevier Inc. All rights reserved.

Waste to Energy at SUNY Cobleskill

DTIC Science & Technology

2011-05-10

Overview on Army Net Zero Concepts • Gasification Intro. • SUNY Cobleskill Center for Environmental Science and Technology. • TURNW2E™ Gasification ...5 GASIFICATION A TECHNOLOGY 2-fer • Waste Reduction • Reduced Logistics for Waste Transportation • Reduced environmental and personnel impact... GASIFICATION Ash ENERGYWaste T ~ 800oC Partial Combustion O/C ~1/3 • Energy Production • Reduced Fuel Usage for transportation • Increased Energy

Interfacial reactions between DBD and porous catalyst in dry methane reforming

NASA Astrophysics Data System (ADS)

Kameshima, Seigo; Mizukami, Ryo; Yamazaki, Takumi; Prananto, Lukman A.; Nozaki, Tomohiro

2018-03-01

Interaction between dielectric barrier discharge (DBD) and porous catalyst in dry methane reforming (CH4  +  CO2  =  2H2  +  2CO) was studied. Coke formation behavior and coke morphology, as well as material conversion and selectivity, over the cross-section of porous pellets was investigated comprehensively by SEM analysis, Raman spectroscopy and pulsed reforming diagnosis, showing DBD and porous pellet interaction is possible only in the interfacial region (the external surface of the pellet): neither generation of DBD nor the diffusion of plasma generated reactive species in the internal micropores is possible. Coke formation and gasification mechanism in nonthermal plasma catalysis of DMR were discussed based on the catalyst effectiveness factor: low-temperature plasma catalysis is equivalent to the high-temperature thermal catalysis.

Hydrogen production by gasification of municipal solid waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robers, R.

1994-05-06

As fossil fuel reserves run lower and lower, and as their continued widespread use leads toward numerous environmental problems, the need for clean and sustainable energy alternatives becomes ever clearer. Hydrogen fuel holds promise as such an energy source, as it burns cleanly and can be extracted from a number of renewable materials such as municipal solid waste (MSW), which is considered to be largely renewable because of its high content of paper and biomass-derived products. A computer model is being developed using Aspen Plus{sup {trademark}} flowsheeting software to simulate a process which produces hydrogen gas from MSW; the modelmore » will later be used in studying the economics of this process and is based on an actual Texaco coal gasification plant design.« less

Heat exchanger for coal gasification process

DOEpatents

Blasiole, George A.

1984-06-19

This invention provides a heat exchanger, particularly useful for systems requiring cooling of hot particulate solids, such as the separated fines from the product gas of a carbonaceous material gasification system. The invention allows effective cooling of a hot particulate in a particle stream (made up of hot particulate and a gas), using gravity as the motive source of the hot particulate. In a preferred form, the invention substitutes a tube structure for the single wall tube of a heat exchanger. The tube structure comprises a tube with a core disposed within, forming a cavity between the tube and the core, and vanes in the cavity which form a flow path through which the hot particulate falls. The outside of the tube is in contact with the cooling fluid of the heat exchanger.

Estimation of Coal Reserves for UCG in the Upper Silesian Coal Basin, Poland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bialecka, Barbara

One of the prospective methods of coal utilization, especially in case of coal resources which are not mineable by means of conventional methods, is underground coal gasification (UCG). This technology allows recovery of coal energy 'in situ' and thus avoid the health and safety risks related to people which are inseparable from traditional coal extraction techniques.In Poland most mining areas are characterized by numerous coal beds where extraction was ceased on account of technical and economic reasons or safety issues. This article presents estimates of Polish hard coal resources, broken down into individual mines, that can constitute the basis ofmore » raw materials for the gasification process. Five mines, representing more than 4 thousand tons, appear to be UCG candidates.« less

Task 3.9 -- Catalytic tar cracking. Semi-annual report, January 1--June 30, 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Young, B.C.; Timpe, R.C.

1995-12-31

Tar produced in the gasification of coal is deleterious to the operation of downstream equipment including fuel cells, gas turbines, hot-gas stream cleanup filters, and pressure swing adsorption systems. Catalytic cracking of tars to smaller hydrocarbons can be an effective means to remove these tars from gas streams and, in the process, generate useful products, e.g., methane gas, which is crucial to the operation of molten carbonate fuel cells. The objectives of this project are to investigate whether gasification tars can be cracked by synthetic nickel-substituted micamontmorillonite, zeolite, or dolomite material; and whether the tars can be cracked selectively bymore » these catalysts to produce a desired liquid and/or gas stream. Results to date are presented in the cited papers.« less

Characterization of solid fuels at pressurized fluidized bed gasification conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zevenhoven, R.; Hupa, M.

1998-07-01

The gasification of co-gasification of solid fuel (coal, peat, wood) in air-blown fluidized bed gasifiers is receiving continued attention as an alternative to entrained flow gasifiers which in general are oxygen-blown. Fluidized bed gasification of wood and wood-waste at elevated pressures, and the so-called air-blown gasification cycle are examples of processes which are under development in Europe. based on complete or partial gasification of a solid fuel in a pressurized fluidized bed. At the same time, fuel characterization data for the combination of temperature, pressure and fuel particle heating rate that is encountered in fluidized bed gasification are very scarce.more » In this paper, quantitative data on the characterization of fuels for advanced combustion and gasification technologies based on fluidized beds are given, as a result from the authors participation in the JOULE 2 extension project on clean coal technology of the European community. Eleven solid fuels, ranging from coal via peat to wood, have been studied under typical fluidized bed gasification conditions: 800--1,000 C, 1--25 bar, fuel heating rate in the order of 100--1,000 C/s. Carbon dioxide was used as gasifying agent. A pressurized thermogravimetric reactor was used for the experiments. The results show that the solid residue yield after pyrolysis/devolatilization increases with pressure and decreases with temperature. For coal, the gasification reactivity of the char increases by a factor of 3 to 4 when pressurizing from 1 to 25 bar, for the younger fuels such as peat and wood, this effect is negligible. Several empirical engineering equations are given which relate the fuel performance to the process parameters and the proximate and chemical analyses of the fuel. A pressure maximum was found at which a maximum gasification reactivity occurs, for practically all fuels, and depending on temperature. It is shown that this can be explained and modeled using a Langmuir-Hinshelwood model.« less

Characterisation of solid fuels at pressurised fluidised bed gasification conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zebenhoven, R.; Hupa, M.

1998-04-01

The gasification or co-gasification of solid fuels (coal, peat, wood) in air-blown fluidised bed gasifiers is receiving continued attention as an alternative to entrained flow gasifiers which in general are oxygen-blown. Fluidised bed gasification of wood and wood-waste at elevated pressures, and the so-called air-blown gasification cycle are examples of processes which are under development in Europe, based on complete or partial gasification of a solid fuel in a pressurised fluidised bed. At the same time, fuel characterisation data for the combination of temperature, pressure and fuel particle heating rate that is encountered in fluidised bed gasification are very scarce.more » Quantitative data on the characterisation of fuels for advanced combustion and gasification technologies based on fluidised beds are given, as a result from our participation to the JOULE 2 extension project on clean coal technology of the European Community. Eleven solid fuels, ranging from coal via peat to wood, have been studied under typical fluidised bed gasification conditions: 800-1000{degrees}C, 1-25 bar, fuel heating rate in the order of 100-1000{degrees}C/s. Carbon dioxide was used as gasifying agent. A pressurised thermogravimetric reactor was used for the experiments. The results show that the solid residue yield after pyrolysis/devolatilisation. increases with pressure and decreases with temperature. For coal, the gasification reactivity of the char increases by a factor of 3 to 4 when pressurising from 1 to 25 bar, for the `younger` fuels such as peat and wood, this effect is negligible. Several empirical, `engineering` equations are given which relate the fuel performance to the process parameters and the proximate and chemical analyses of the fuel. A pressure maximum was found at which a maximum gasification reactivity occurs, for practically all fuels, and depending on temperature. It is shown that this can be explained and modelled using a Langmuir-Hinshelwood model.« less

Numerical investigation of the staged gasification of wet wood

NASA Astrophysics Data System (ADS)

Donskoi, I. G.; Kozlov, A. N.; Svishchev, D. A.; Shamanskii, V. A.

2017-04-01

Gasification of wooden biomass makes it possible to utilize forestry wastes and agricultural residues for generation of heat and power in isolated small-scale power systems. In spite of the availability of a huge amount of cheap biomass, the implementation of the gasification process is impeded by formation of tar products and poor thermal stability of the process. These factors reduce the competitiveness of gasification as compared with alternative technologies. The use of staged technologies enables certain disadvantages of conventional processes to be avoided. One of the previously proposed staged processes is investigated in this paper. For this purpose, mathematical models were developed for individual stages of the process, such as pyrolysis, pyrolysis gas combustion, and semicoke gasification. The effect of controlling parameters on the efficiency of fuel conversion into combustible gases is studied numerically using these models. For the controlling parameter are selected heat inputted into a pyrolysis reactor, the excess of oxidizer during gas combustion, and the wood moisture content. The process efficiency criterion is the gasification chemical efficiency accounting for the input of external heat (used for fuel drying and pyrolysis). The generated regime diagrams represent the gasification efficiency as a function of controlling parameters. Modeling results demonstrate that an increase in the fraction of heat supplied from an external source can result in an adequate efficiency of the wood gasification through the use of steam generated during drying. There are regions where it is feasible to perform incomplete combustion of the pyrolysis gas prior to the gasification. The calculated chemical efficiency of the staged gasification is as high as 80-85%, which is 10-20% higher that in conventional single-stage processes.

The Use of the Visualisation of Multidimensional Data Using PCA to Evaluate Possibilities of the Division of Coal Samples Space Due to their Suitability for Fluidised Gasification

NASA Astrophysics Data System (ADS)

Jamróz, Dariusz; Niedoba, Tomasz; Surowiak, Agnieszka; Tumidajski, Tadeusz

2016-09-01

Methods serving to visualise multidimensional data through the transformation of multidimensional space into two-dimensional space, enable to present the multidimensional data on the computer screen. Thanks to this, qualitative analysis of this data can be performed in the most natural way for humans, through the sense of sight. An example of such a method of multidimensional data visualisation is PCA (principal component analysis) method. This method was used in this work to present and analyse a set of seven-dimensional data (selected seven properties) describing coal samples obtained from Janina and Wieczorek coal mines. Coal from these mines was previously subjected to separation by means of a laboratory ring jig, consisting of ten rings. With 5 layers of both types of coal (with 2 rings each) were obtained in this way. It was decided to check if the method of multidimensional data visualisation enables to divide the space of such divided samples into areas with different suitability for the fluidised gasification process. To that end, the card of technological suitability of coal was used (Sobolewski et al., 2012; 2013), in which key, relevant and additional parameters, having effect on the gasification process, were described. As a result of analyses, it was stated that effective determination of coal samples suitability for the on-surface gasification process in a fluidised reactor is possible. The PCA method enables the visualisation of the optimal subspace containing the set requirements concerning the properties of coals intended for this process.

Characteristics of the microwave pyrolysis and microwave CO2-assisted gasification of dewatered sewage sludge.

PubMed

Chun, Young Nam; Jeong, Byeo Ri

2017-07-28

Microwave drying-pyrolysis or drying-gasification characteristics were examined to convert sewage sludge into energy and resources. The gasification was carried out with carbon dioxide as a gasifying agent. The examination results were compared with those of the conventional heating-type electric furnace to compare both product characteristics. Through the pyrolysis or gasification, gas, tar, and char were generated as products. The produced gas was the largest component of each process, followed by the sludge char and the tar. During the pyrolysis process, the main components of the produced gas were hydrogen and carbon monoxide, with a small amount of hydrocarbons such as methane and ethylene. In the gasification process, however, the amount of carbon monoxide was greater than the amount of hydrogen. In microwave gasification, a large amount of heavy tar was produced. The largest amount of benzene in light tar was generated from the pyrolysis or gasification. Ammonia and hydrogen cyanide, which are precursors of NO x , were also generated. In the microwave heating method, the sludge char produced by pyrolysis and gasification had pores in the mesopore range. This could be explained that the gas obtained from the microwave pyrolysis or gasification of the wet sewage sludge can be used as an alternative fuel, but the tar and NO x precursors in the produced gas should be treated. Sludge char can be used as a biomass solid fuel or as a tar removal adsorbent if necessary.

Fossil energy program

NASA Astrophysics Data System (ADS)

McNeese, L. E.

1981-12-01

The progress made during the period from July 1 through September 30 for the Oak Ridge National Laboratory research and development projects in support of the increased utilization of coal and other fossil fuels as sources of clean energy is reported. The following topics are discussed: coal conversion development, chemical research and development, materials technology, fossil energy materials program, liquefaction projects, component development, process analysis, environmental control technology, atmospheric fluidized bed combustion, underground coal gasification, coal preparation and waste utilization.

Assessment of the SRI Gasification Process for Syngas Generation with HTGR Integration -- White Paper

DOE Office of Scientific and Technical Information (OSTI.GOV)

A.M. Gandrik

2012-04-01

This white paper is intended to compare the technical and economic feasibility of syngas generation using the SRI gasification process coupled to several high-temperature gas-cooled reactors (HTGRs) with more traditional HTGR-integrated syngas generation techniques, including: (1) Gasification with high-temperature steam electrolysis (HTSE); (2) Steam methane reforming (SMR); and (3) Gasification with SMR with and without CO2 sequestration.

Supercritical gasification for the treatment of o-cresol wastewater.

PubMed

Wei, Chao-hai; Hu, Cheng-sheng; Wu, Chao-fei; Yan, Bo

2006-01-01

The supercritical water gasification of phenolic wastewater without oxidant was performed to degrade pollutants and produce hydrogen-enriched gases. The simulated o-cresol wastewater was gasified at 440-650 degrees C and 27.6 MPa in a continuous Inconel 625 reactor with the residence time of 0.42-1.25 min. The influence of the reaction temperature, residence time, pressure, catalyst, oxidant and the pollutant concentration on the gasification efficiency was investigated. Higher temperature and longer residence time enhanced the o-cresol gasification. The TOC removal rate and hydrogen gasification rate were 90.6% and 194.6%, respectively, at the temperature of 650 degrees C and the residence time of 0.83 min. The product gas was mainly composed of H2, CO2, CH4 and CO, among which the total molar percentage of H2 and CH4 was higher than 50%. The gasification efficiency decreased with the pollutant concentration increasing. Both the catalyst and oxidant could accelerate the hydrocarbon gasification at a lower reaction temperature, in which the catalyst promoted H2 production and the oxidant enhanced CO2 generation. The intermediates of liquid effluents were analyzed and phenol was found to be the main composition. The results indicate that the supercritical gasification is a promising way for the treatment of hazardous organic wastewater.

Considerations Based on Reaction Rate on Char Gasification Behavior in Two-stage Gasifier for Biomass

NASA Astrophysics Data System (ADS)

Taniguchi, Miki; Nishiyama, Akio; Sasauchi, Kenichi; Ito, Yusuke; Akamatsu, Fumiteru

In order to develop a small-scale gasifier in which biomass can be converted to energy with high efficiency, we planned a gasification process that consists of two parts: pyrolysis part (rotary kiln) and gasification part (downdraft gasifier). We performed fundamental experiments on gasification part and discussed the appropriate conditions such as air supply location, air ratio, air temperature and hearth load. We considered the results by calculating reaction rates of representative reactions on char gasification part and found that water gas reaction is dominant in the reduction area and its behavior gives important information to decide the adequate length of the char layer.

Development of Kinetics and Mathematical Models for High Pressure Gasification of Lignite-Switchgrass Blends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agrawal, Pradeep K.

The overall objective of the current project was to investigate the high pressure gasification characteristics of a feed containing both coal and biomass. The two feed types differ in their ash contents and ash composition, particularly the alkali content. Gasification of a combined feed of coal and biomass has the potential for considerable synergies that might lead to a dramatic improvement in process economics and flexibility. The proposed study aimed to develop a detailed understanding of the chemistry, kinetics, and transport effects during high pressure gasification of coal-biomass blend feed. Specifically, we studied to develop: (a) an understanding of themore » catalytic effect of alkali and other inorganic species present in the biomass and coal, (b) an understanding of processing conditions under which synergistic effects of the blending of coal and biomass might be observed. This included the role of particle size, residence time, and proximity of the two feed types, (c) kinetics of high pressure gasification of individual feeds as well as the blends, and (d) development of mathematical models that incorporate kinetics and transport models to enable prediction of gasification rate at a given set of operating conditions, and (e) protocols to extend the results to other feed resources. The goal was to provide a fundamental understanding of the gasification process and guide in optimizing the configurations and design of the next generation of gasifiers. The approach undertaken was centered on two basic premises: (1) the gasification for small particles without internal mass transfer limitations can be treated as the sum of two processes in series (pyrolysis and char gasification) , and (2) the reactivity of the char generated during pyrolysis not only depends on the pressure and temperature but is also affected by the heating rates. Thus low heating rates (10-50 °C/min) typical of PTGA fail to produce char that would typically be formed at high heating rates (~10 4 °C/sec), encountered in entrained flow gasifiers. The char morphology, also a function of the heating rate, would influence the transport rates during the char gasification phase. Thus, heating rate plays a critical role through which both, pyrolysis and char gasification, are interconnected. We utilized two complementary gasification experiments: PEFR (pressurized entrained flow gasifier) and PTGA (pressurized thermo-gravimetric analyzer). The PEFR allowed us to study gasification at pressures, temperatures, and heating rates relevant for coal-biomass gasifiers. The PTGA work was useful in understanding the basic chemistry of the evolution of various gaseous species during pyrolysis. These results helped improved our understanding of the chemistry and chemical changes during pyrolysis. The role alkali metals and other inorganics in char gasification using steam and/or CO 2 was investigated. Finally, the mathematical models for char gasification without the transport effects were developed at commercial operating conditions.« less

Technology Assessment Report: Aqueous Sludge Gasification Technologies

EPA Science Inventory

The study reveals that sludge gasification is a potentially suitable alternative to conventional sludge handling and disposal methods. However, very few commercial operations are in existence. The limited pilot, demonstration or commercial application of gasification technology t...

Studies on biomass char gasification and dynamics

NASA Astrophysics Data System (ADS)

You, Zhanping; You, Shijun; Ma, Xiaoyan

2018-01-01

The gasification performances of two kinds of biomass char by experiment methods are studied, including conversion rate and gasification gas component with temperature and time. Experimental results show that gasification temperature has important effects on the conversion rate and gas component. In the range of experimental temperature, char conversion rates are no more than 30.0%. The apparent activation energies and apparent reaction frequency factors of two biomass chars are obtained through kinetic studies.

Comparison of the co-gasification of sewage sludge and food wastes and cost-benefit analysis of gasification- and incineration-based waste treatment schemes.

PubMed

You, Siming; Wang, Wei; Dai, Yanjun; Tong, Yen Wah; Wang, Chi-Hwa

2016-10-01

The compositions of food wastes and their co-gasification producer gas were compared with the existing data of sewage sludge. Results showed that food wastes are more favorable than sewage sludge for co-gasification based on residue generation and energy output. Two decentralized gasification-based schemes were proposed to dispose of the sewage sludge and food wastes in Singapore. Monte Carlo simulation-based cost-benefit analysis was conducted to compare the proposed schemes with the existing incineration-based scheme. It was found that the gasification-based schemes are financially superior to the incineration-based scheme based on the data of net present value (NPV), benefit-cost ratio (BCR), and internal rate of return (IRR). Sensitivity analysis was conducted to suggest effective measures to improve the economics of the schemes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synergistic combination of biomass torrefaction and co-gasification: Reactivity studies.

PubMed

Zhang, Yan; Geng, Ping; Liu, Rui

2017-12-01

Two typical biomass feedstocks obtained from woody wastes and agricultural residues were torrefied or mildly pyrolized in a fixed-bed reactor. Effects of the torrefaction conditions on product distributions, compositional and energetic properties of the solid products, char gasification reactivity, and co-gasification behavior between coal and torrefied solids were systematically investigated. Torrefaction pretreatment produced high quality bio-solids with not only increased energy density, but also concentrated alkali and alkaline earth metals (AAEM). As a consequence of greater retention of catalytic elements in the solid products, the chars derived from torrefied biomass exhibited a faster conversion than those derived from raw biomass during CO 2 gasification. Furthermore, co-gasification of coal/torrefied biomass blends exhibited stronger synergy compared to the coal/raw biomass blends. The results and insights provided by this study filled a gap in understanding synergy during co-gasification of coal and torrefied biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biomass from intensively cultured plantations as an energy, chemical, and nutritional feedstock

Treesearch

John E. Phelps

1983-01-01

Several technologies are described that have been developed to convert wood to fuel, chemicals or food products. Biomass from intensively cultured plantations has potential as a source of material for these energy related technologies. The technologies discussed here include: pyrolysis, gasification, liquefaction, hydrolysis, chemicals from lignin and hemicelluloses,...

Life cycle assessment of pyrolysis, gasification and incineration waste-to-energy technologies: Theoretical analysis and case study of commercial plants.

PubMed

Dong, Jun; Tang, Yuanjun; Nzihou, Ange; Chi, Yong; Weiss-Hortala, Elsa; Ni, Mingjiang

2018-06-01

Municipal solid waste (MSW) pyrolysis and gasification are in development, stimulated by a more sustainable waste-to-energy (WtE) option. Since comprehensive comparisons of the existing WtE technologies are fairly rare, this study aims to conduct a life cycle assessment (LCA) using two sets of data: theoretical analysis, and case studies of large-scale commercial plants. Seven systems involving thermal conversion (pyrolysis, gasification, incineration) and energy utilization (steam cycle, gas turbine/combined cycle, internal combustion engine) are modeled. Theoretical analysis results show that pyrolysis and gasification, in particular coupled with a gas turbine/combined cycle, have the potential to lessen the environmental loadings. The benefits derive from an improved energy efficiency leading to less fossil-based energy consumption, and the reduced process emissions by syngas combustion. Comparison among the four operating plants (incineration, pyrolysis, gasification, gasification-melting) confirms a preferable performance of the gasification plant attributed to syngas cleaning. The modern incineration is superior over pyrolysis and gasification-melting at present, due to the effectiveness of modern flue gas cleaning, use of combined heat and power (CHP) cycle, and ash recycling. The sensitivity analysis highlights a crucial role of the plant efficiency and pyrolysis char land utilization. The study indicates that the heterogeneity of MSW and syngas purification technologies are the most relevant impediments for the current pyrolysis/gasification-based WtE. Potential development should incorporate into all process aspects to boost the energy efficiency, improve incoming waste quality, and achieve efficient residues management. Copyright © 2018 Elsevier B.V. All rights reserved.

TEXACO GASIFICATION PROCESS - INNOVATIVE TECHNOLOGY EVALUATION REPORT

EPA Science Inventory

This report summarizes the evaluation of the Texaco Gasification Process (TGP) conducted under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) Program. The Texaco Gasification Process was developed by Texaco Inc. The TGP is a comm...

Factors affecting activated carbon-based catalysts for selective hydrogen sulfide oxidation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Huixing; Monnell, J.D.; Alvin, M.A.

2008-09-01

The primary product of coal gasification processes is synthesis gas (syngas), a mixture of CO, H2, CO2, H2O and a number of minor components. Among the most significant minor components in syngas is hydrogen sulfide (H2S). In addition to its adverse environmental impact, H2S poisons the catalysts and hydrogen purification membranes, and causes severe corrosion in gas turbines. Technologies that can remove H2S from syngas and related process streams are, therefore, of considerable practical interest. To meet this need, we work towards understanding the mechanism by which prospective H2S catalysts perform in simulated fuel gas conditions. Specifically, we show thatmore » for low-temperature gas clean-up (~1408C) using activated carbon fibers and water plays a significant role in H2S binding and helps to prolong the lifetime of the material. Basic surface functional groups were found to be imperative for significant conversion of H2S to daughter compounds, whereas metal oxides (La and Ce) did little to enhance this catalysis. We show that although thermal regeneration of the material is possible, the regenerated material has a substantially lower catalytic and sorption capacity.« less

Small Scale Gasification Application and Perspectives in Circular Economy

NASA Astrophysics Data System (ADS)

Klavins, Maris; Bisters, Valdis; Burlakovs, Juris

2018-06-01

Gasification is the process converting solid fuels as coal and organic plant matter, or biomass into combustible gas, called syngas. Gasification is a thermal conversion process using carbonaceous fuel, and it differs substantially from other thermal processes such as incineration or pyrolysis. The process can be used with virtually any carbonaceous fuel. It is an endothermic thermal conversion process, with partial oxidation being the dominant feature. Gasification converts various feedstock including waste to a syngas. Instead of producing only heat and electricity, synthesis gas produced by gasification may be transformed into commercial products with higher value as transport fuels, fertilizers, chemicals and even to substitute natural gas. Thermo-chemical conversion of biomass and solid municipal waste is developing as a tool to promote the idea of energy system without fossil fuels to a reality. In municipal solid waste management, gasification does not compete with recycling, moreover it enhances recycling programs. Pre-processing and after-processing must increase the amount of recyclables in the circular economy. Additionally, end of life plastics can serve as an energy feedstock for gasification as otherwise it cannot be sorted out and recycled. There is great potential for application of gasification technology within the biomass waste and solid waste management sector. Industrial self-consumption in the mode of combined heat and power can contribute to sustainable economic development within a circular economy.

Thermogravimetric and model-free kinetic studies on CO2 gasification of low-quality, high-sulphur Indian coals

NASA Astrophysics Data System (ADS)

Das, Tonkeswar; Saikia, Ananya; Mahanta, Banashree; Choudhury, Rahul; Saikia, Binoy K.

2016-10-01

Coal gasification with CO2 has emerged as a cleaner and more efficient way for the production of energy, and it offers the advantages of CO2 mitigation policies through simultaneous CO2 sequestration. In the present investigation, a feasibility study on the gasification of three low-quality, high-sulphur coals from the north-eastern region (NER) of India in a CO2 atmosphere using thermogravimetric analysis (TGA-DTA) has been made in order to have a better understanding of the physical and chemical characteristics in the process of gasification of coal. Model-free kinetics was applied to determine the activation energies (E) and pre-exponential factors (A) of the CO2 gasification process of the coals. Multivariate non-linear regression analyses were performed to find out the formal mechanisms, kinetic model, and the corresponding kinetic triplets. The results revealed that coal gasification with CO2 mainly occurs in the temperature range of 800∘-1400∘C and a maximum of at around 1100∘C. The reaction mechanisms responsible for CO2 gasification of the coals were observed to be of the ` nth order with autocatalysis (CnB)' and ` nth order (Fn) mechanism'. The activation energy of the CO2 gasification was found to be in the range 129.07-146.81 kJ mol-1.

Research and application of surface heat treatment for multipulse laser ablation of materials

NASA Astrophysics Data System (ADS)

Cai, Song; Chen, Genyu; Zhou, Cong

2015-11-01

This study analysed a laser ablation platform and built heat transfer equations for multipulse laser ablation of materials. The equations include three parts: laser emission after the material melt and gasification; end of laser emission after the material melts and there is the presence of a super-hot layer and solid-phase heat transfer changes during material ablation. For each of the three parts, the effects of evaporation, plasma shielding and energy accumulation under the pulse interval were considered. The equations are reasonable, and all the required parameters are only related to the laser parameters and material properties, allowing the model to have a certain versatility and practicability. The model was applied for numerical simulation of the heat transfer characteristics in the multipulse laser ablation of bronze and diamond. Next, experiments were conducted to analyse the topography of a bronze-bonded diamond grinding wheel after multipulse laser ablation. The theoretical analysis and experimental results showed that multipulse laser can merge the truing and dressing on a bronze-bonded diamond grinding wheel. This study provides theoretical guidance for optimising the process parameters in the laser ablation of a bronze-bonded diamond grinding wheel. A comparative analysis showed that the numerical solution to the model is in good agreement with the experimental data, thus verifying the correctness and feasibility of the heat transfer model.

78 FR 52764 - Extension of Public Comment Period Hydrogen Energy California's Integrated Gasification Combined...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-26

... DEPARTMENT OF ENERGY Extension of Public Comment Period Hydrogen Energy California's Integrated Gasification Combined Cycle Project Preliminary Staff Assessment and Draft Environmental Impact Statement... California's Integrated Gasification Combined Cycle Project Preliminary Staff Assessment/Draft Environmental...

Preparation of activated carbons from corn cob catalyzed by potassium salts and subsequent gasification with CO2.

PubMed

Tsai, W T; Chang, C Y; Wang, S Y; Chang, C F; Chien, S F; Sun, H F

2001-06-01

In the present study, granular activated carbons were prepared from agricultural waste corn cob by chemical activation with potassium salts and/or physical activation with CO2. Under the experimental conditions investigated, potassium hydroxide (KOH) and potassium carbonate (K2CO3) were effective activating agents for chemical activation during a ramping period of 10 degrees C/min and subsequent gasification (i.e., physical activation) at a soaking period of 800 degrees C. Large BET surface areas (>1,600 m2/g) of activated carbons were thus obtained by the combined activation. In addition, this study clearly showed that the porosity created in the acid-unwashed carbon products is substantially lower than that of acid-washed carbon products due to potassium salts left in the pore structure.

Theoretical Study of Sodium Effect on the Gasification of Carbonaceous Materials with Carbon Dioxide.

PubMed

Calderón, Lucas A; Garza, Jorge; Espinal, Juan F

2015-12-24

The effect of sodium on the thermodynamics and kinetics of carbon gasification with carbon dioxide was studied by using quantum chemistry methods. Specifically, in the density functional context, two exchange-correlation functionals were used: B3LYP and M06. Some results obtained by these exchange-correlation functionals were contrasted with those obtained by the CCSD(T) method. It was found that density functional theory gives similar conclusions with respect to the coupled-cluster method. As one important conclusion we can mention that the thermodynamics of carbon monoxide desorption is not favored by the sodium presence. However, the presence of this metal induces: (a) an easier formation of one semiquinone group, (b) the dissociation of carbon dioxide, and (c) an increment on the CO desorption rate for one of the proposed pathways.

Solar coal gasification reactor with pyrolysis gas recycle

DOEpatents

Aiman, William R.; Gregg, David W.

1983-01-01

Coal (or other carbonaceous matter, such as biomass) is converted into a duct gas that is substantially free from hydrocarbons. The coal is fed into a solar reactor (10), and solar energy (20) is directed into the reactor onto coal char, creating a gasification front (16) and a pyrolysis front (12). A gasification zone (32) is produced well above the coal level within the reactor. A pyrolysis zone (34) is produced immediately above the coal level. Steam (18), injected into the reactor adjacent to the gasification zone (32), reacts with char to generate product gases. Solar energy supplies the energy for the endothermic steam-char reaction. The hot product gases (38) flow from the gasification zone (32) to the pyrolysis zone (34) to generate hot char. Gases (38) are withdrawn from the pyrolysis zone (34) and reinjected into the region of the reactor adjacent the gasification zone (32). This eliminates hydrocarbons in the gas by steam reformation on the hot char. The product gas (14) is withdrawn from a region of the reactor between the gasification zone (32) and the pyrolysis zone (34). The product gas will be free of tar and other hydrocarbons, and thus be suitable for use in many processes.

78 FR 54640 - Extension of Public Comment Period Hydrogen Energy California's Integrated Gasification Combined...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-05

... DEPARTMENT OF ENERGY Extension of Public Comment Period Hydrogen Energy California's Integrated Gasification Combined Cycle Project Preliminary Staff Assessment and Draft Environmental Impact Statement... Integrated Gasification Combined Cycle Project Preliminary Staff Assessment and Draft Environmental Impact...

77 FR 58022 - Montana Regulatory Program

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-19

... additions of statutory definitions of approximate original contour, in situ coal gasification, and recovery... intends to promulgate regulations pertaining to in situ coal gasification within one year. The statutory... which do not have Federal counterparts under SMCRA: ``in situ coal gasification'' and ``recovery fluid...

Method for increasing steam decomposition in a coal gasification process

DOEpatents

Wilson, Marvin W.

1988-01-01

The gasification of coal in the presence of steam and oxygen is significantly enhanced by introducing a thermochemical water-splitting agent such as sulfuric acid, into the gasifier for decomposing the steam to provide additional oxygen and hydrogen usable in the gasification process for the combustion of the coal and enrichment of the gaseous gasification products. The addition of the water-splitting agent into the gasifier also allows for the operation of the reactor at a lower temperature.

Method for increasing steam decomposition in a coal gasification process

DOEpatents

Wilson, M.W.

1987-03-23

The gasification of coal in the presence of steam and oxygen is significantly enhanced by introducing a thermochemical water- splitting agent such as sulfuric acid, into the gasifier for decomposing the steam to provide additional oxygen and hydrogen usable in the gasification process for the combustion of the coal and enrichment of the gaseous gasification products. The addition of the water-splitting agent into the gasifier also allows for the operation of the reactor at a lower temperature.

Activated carbon derived from carbon residue from biomass gasification and its application for dye adsorption: Kinetics, isotherms and thermodynamic studies.

PubMed

Maneerung, Thawatchai; Liew, Johan; Dai, Yanjun; Kawi, Sibudjing; Chong, Clive; Wang, Chi-Hwa

2016-01-01

In this work, activated carbon (AC) as an effective and low-cost adsorbent was successfully prepared from carbon residue (or char, one of the by-products from woody biomass gasification) via physical activation. The surface area of char was significantly increased from 172.24 to 776.46m(2)/g after steam activation at 900°C. The obtained activated carbons were then employed for the adsorption of dye (Rhodamine B) and it was found that activated carbon obtained from steam activation exhibited the highest adsorption capability, which is mainly attributed to the higher surface area and the abundance of hydroxyl (-OH) and carboxyl (-COOH) groups on the activated carbon surface. Moreover, it was also found that the adsorption capability significantly increased under the basic condition, which can be attributed to the increased electrostatic interaction between the deprotonated (negatively charged) activated carbon and dye molecules. Furthermore, the equilibrium data were fitted into different adsorption isotherms and found to fit well with Langmuir model (indicating that dye molecules form monolayer coverage on activated carbon) with a maximum monolayer adsorption capability of 189.83mg/g, whereas the adsorption kinetics followed the pseudo-second-order kinetics. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of available data on the geohydrology, soil chemistry, and ground-water chemistry of Gas Works Park and surrounding region, Seattle, Washington

USGS Publications Warehouse

Sabol, M.A.; Turney, G.L.; Ryals, G.N.

1988-01-01

Gas Works Park, in Seattle, Washington, is located at the site of an abandon gasification plant on Lake Union. Wastes deposited during 50 years of plant operations (1906-1956) have extended the shore line 100 ft and left the park soil contaminated with a number of hazardous material. Soil contaminants include polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls, pesticides, volatile organic compounds, cyanide, and metals. PAHs and metals have been detected in Lake Union sediments. Maximum total PAH concentrations exceeded 100 million micrograms/kilogram in some places in the soils of the park at 6-inch depths and in some lake sediments. Other contaminants present are much lower in concentrations. The park is on glacial drift overlain by gasification waste materials and clean fill. Waste materials include sand and gravels, mixed with lampblack, oil, bricks, and other industrial wastes. Groundwater flows through the soils and waste toward Lake Union. Vertical groundwater movement is uncertain, but is assumed to be upward near Lake Union. Concentrations of most soil contaminants are probably low in the groundwater and in Lake Union due to the low solubilities and high sorptive characteristics of these contaminants. However, no water quality data are available to confirm this premise. (USGS)

Experiments on torrefied wood pellet: study by gasification and characterization for waste biomass to energy applications.

PubMed

Rollinson, Andrew N; Williams, Orla

2016-05-01

Samples of torrefied wood pellet produced by low-temperature microwave pyrolysis were tested through a series of experiments relevant to present and near future waste to energy conversion technologies. Operational performance was assessed using a modern small-scale downdraft gasifier. Owing to the pellet's shape and surface hardness, excellent flow characteristics were observed. The torrefied pellet had a high energy density, and although a beneficial property, this highlighted the present inflexibility of downdraft gasifiers in respect of feedstock tolerance due to the inability to contain very high temperatures inside the reactor during operation. Analyses indicated that the torrefaction process had not significantly altered inherent kinetic properties to a great extent; however, both activation energy and pre-exponential factor were slightly higher than virgin biomass from which the pellet was derived. Thermogravimetric analysis-derived reaction kinetics (CO2 gasification), bomb calorimetry, proximate and ultimate analyses, and the Bond Work Index grindability test provided a more comprehensive characterization of the torrefied pellet's suitability as a fuel for gasification and also other combustion applications. It exhibited significant improvements in grindability energy demand and particle size control compared to other non-treated and thermally treated biomass pellets, along with a high calorific value, and excellent resistance to water.

Experiments on torrefied wood pellet: study by gasification and characterization for waste biomass to energy applications

PubMed Central

Rollinson, Andrew N.; Williams, Orla

2016-01-01

Samples of torrefied wood pellet produced by low-temperature microwave pyrolysis were tested through a series of experiments relevant to present and near future waste to energy conversion technologies. Operational performance was assessed using a modern small-scale downdraft gasifier. Owing to the pellet's shape and surface hardness, excellent flow characteristics were observed. The torrefied pellet had a high energy density, and although a beneficial property, this highlighted the present inflexibility of downdraft gasifiers in respect of feedstock tolerance due to the inability to contain very high temperatures inside the reactor during operation. Analyses indicated that the torrefaction process had not significantly altered inherent kinetic properties to a great extent; however, both activation energy and pre-exponential factor were slightly higher than virgin biomass from which the pellet was derived. Thermogravimetric analysis-derived reaction kinetics (CO2 gasification), bomb calorimetry, proximate and ultimate analyses, and the Bond Work Index grindability test provided a more comprehensive characterization of the torrefied pellet's suitability as a fuel for gasification and also other combustion applications. It exhibited significant improvements in grindability energy demand and particle size control compared to other non-treated and thermally treated biomass pellets, along with a high calorific value, and excellent resistance to water. PMID:27293776

Comparative life cycle assessment (LCA) of construction and demolition (C&D) derived biomass and U.S. northeast forest residuals gasification for electricity production.

PubMed

Nuss, Philip; Gardner, Kevin H; Jambeck, Jenna R

2013-04-02

With the goal to move society toward less reliance on fossil fuels and the mitigation of climate change, there is increasing interest and investment in the bioenergy sector. However, current bioenergy growth patterns may, in the long term, only be met through an expansion of global arable land at the expense of natural ecosystems and in competition with the food sector. Increasing thermal energy recovery from solid waste reduces dependence on fossil- and biobased energy production while enhancing landfill diversion. Using inventory data from pilot processes, this work assesses the cradle-to-gate environmental burdens of plasma gasification as a route capable of transforming construction and demolition (C&D) derived biomass (CDDB) and forest residues into electricity. Results indicate that the environmental burdens associated with CDDB and forest residue gasification may be similar to conventional electricity generation. Land occupation is lowest when CDDB is used. Environmental impacts are to a large extent due to coal cogasified, coke used as gasifier bed material, and fuel oil cocombusted in the steam boiler. However, uncertainties associated with preliminary system designs may be large, particularly the heat loss associated with pilot scale data resulting in overall low efficiencies of energy conversion to electricity; a sensitivity analysis assesses these uncertainties in further detail.

Conversion of municipal solid waste to hydrogen

NASA Astrophysics Data System (ADS)

Richardson, J. H.; Rogers, R. S.; Thorsness, C. B.

1995-04-01

LLNL and Texaco are cooperatively developing a physical and chemical treatment method for the conversion of municipal solid waste (MSW) to hydrogen via the steps of hydrothermal pretreatment, gasification and purification. LLNL's focus has been on hydrothermal pretreatment of MSW in order to prepare a slurry of suitable viscosity and heating value to allow efficient and economical gasification and hydrogen production. The project has evolved along 3 parallel paths: laboratory scale experiments, pilot scale processing, and process modeling. Initial laboratory-scale MSW treatment results (e.g., viscosity, slurry solids content) over a range of temperatures and times with newspaper and plastics will be presented. Viscosity measurements have been correlated with results obtained at MRL. A hydrothermal treatment pilot facility has been rented from Texaco and is being reconfigured at LLNL; the status of that facility and plans for initial runs will be described. Several different operational scenarios have been modeled. Steady state processes have been modeled with ASPEN PLUS; consideration of steam injection in a batch mode was handled using continuous process modules. A transient model derived from a general purpose packed bed model is being developed which can examine the aspects of steam heating inside the hydrothermal reactor vessel. These models have been applied to pilot and commercial scale scenarios as a function of MSW input parameters and have been used to outline initial overall economic trends. Part of the modeling, an overview of the MSW gasification process and the modeling of the MSW as a process material, was completed by a DOE SERS (Science and Engineering Research Semester) student. The ultimate programmatic goal is the technical demonstration of the gasification of MSW to hydrogen at the laboratory and pilot scale and the economic analysis of the commercial feasibility of such a process.

Thermal degradation of paper industry wastes from a recovered paper mill using TGA. Characterization and gasification test.

PubMed

Arenales Rivera, Jorge; Pérez López, Virginia; Ramos Casado, Raquel; Sánchez Hervás, José-María

2016-01-01

In this survey, a refuse derived fuel (RDF) was produced from paper industry wastes through a mechanical treatment (MT). The two main wastes generated from a recovered paper mill were rejects and de-inking sludge, which were produced principally in the pulping and de-inking processes, respectively. This work presents raw wastes characterization, fuel preparation and gasification tests performed in a circulating fluidized bed (CFB) gasifier pilot plant. The characterization was carried out by proximate and ultimate analysis. Several blends of pre-conditioned rejects and de-inking sludge were densified by means of pelletizing, studying the energy consumption and its quality properties. Besides, thermal degradation of blends was studied under thermogravimetric analysis (TGA). The experimental runs were made from 30 to 900°C in nitrogen atmosphere at three heating ranges, β=5, 10 and 20°C/min. Two thermal stages were identified during the thermal degradation, which are linked to cellulose and plastic degradation. In addition, kinetics parameters were estimated by the application of non-isothermal methods: Kissinger-Akahira-Sunose (KAS), Flynn-Ozawa-Wall (FOW) and Coats and Redfern. The activation energy values were about 140-160 kJ/mol and 60-80 kJ/mol for plastic and cellulosic materials, respectively. Regarding waste valorisation, a blend composed of 95% of rejects and 5% of de-inking sludge was selected for gasification tests. The energy consumption during the preparation was recorded and a gasification tests were done to prove the usability of these pellets in a CFB gasifier. The main results were a net calorific value (NCV) of 5 MJ/Nm(3) and a total tar content of 11.44 g/Nm(3) at an equivalence ratio (ER) of 0.3. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hydrothermal Gasification for Waste to Energy

NASA Astrophysics Data System (ADS)

Epps, Brenden; Laser, Mark; Choo, Yeunun

2014-11-01

Hydrothermal gasification is a promising technology for harvesting energy from waste streams. Applications range from straightforward waste-to-energy conversion (e.g. municipal waste processing, industrial waste processing), to water purification (e.g. oil spill cleanup, wastewater treatment), to biofuel energy systems (e.g. using algae as feedstock). Products of the gasification process are electricity, bottled syngas (H2 + CO), sequestered CO2, clean water, and inorganic solids; further chemical reactions can be used to create biofuels such as ethanol and biodiesel. We present a comparison of gasification system architectures, focusing on efficiency and economic performance metrics. Various system architectures are modeled computationally, using a model developed by the coauthors. The physical model tracks the mass of each chemical species, as well as energy conversions and transfers throughout the gasification process. The generic system model includes the feedstock, gasification reactor, heat recovery system, pressure reducing mechanical expanders, and electricity generation system. Sensitivity analysis of system performance to various process parameters is presented. A discussion of the key technological barriers and necessary innovations is also presented.

Biomass waste gasification - Can be the two stage process suitable for tar reduction and power generation?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sulc, Jindrich; Stojdl, Jiri; Richter, Miroslav

2012-04-15

Highlights: Black-Right-Pointing-Pointer Comparison of one stage (co-current) and two stage gasification of wood pellets. Black-Right-Pointing-Pointer Original arrangement with grate-less reactor and upward moving bed of the pellets. Black-Right-Pointing-Pointer Two stage gasification leads to drastic reduction of tar content in gas. Black-Right-Pointing-Pointer One stage gasification produces gas with higher LHV at lower overall ER. Black-Right-Pointing-Pointer Content of ammonia in gas is lower in two stage moving bed gasification. - Abstract: A pilot scale gasification unit with novel co-current, updraft arrangement in the first stage and counter-current downdraft in the second stage was developed and exploited for studying effects of two stagemore » gasification in comparison with one stage gasification of biomass (wood pellets) on fuel gas composition and attainable gas purity. Significant producer gas parameters (gas composition, heating value, content of tar compounds, content of inorganic gas impurities) were compared for the two stage and the one stage method of the gasification arrangement with only the upward moving bed (co-current updraft). The main novel features of the gasifier conception include grate-less reactor, upward moving bed of biomass particles (e.g. pellets) by means of a screw elevator with changeable rotational speed and gradual expanding diameter of the cylindrical reactor in the part above the upper end of the screw. The gasifier concept and arrangement are considered convenient for thermal power range 100-350 kW{sub th}. The second stage of the gasifier served mainly for tar compounds destruction/reforming by increased temperature (around 950 Degree-Sign C) and for gasification reaction of the fuel gas with char. The second stage used additional combustion of the fuel gas by preheated secondary air for attaining higher temperature and faster gasification of the remaining char from the first stage. The measurements of gas composition and tar compound contents confirmed superiority of the two stage gasification system, drastic decrease of aromatic compounds with two and higher number of benzene rings by 1-2 orders. On the other hand the two stage gasification (with overall ER = 0.71) led to substantial reduction of gas heating value (LHV = 3.15 MJ/Nm{sup 3}), elevation of gas volume and increase of nitrogen content in fuel gas. The increased temperature (>950 Degree-Sign C) at the entrance to the char bed caused also substantial decrease of ammonia content in fuel gas. The char with higher content of ash leaving the second stage presented only few mass% of the inlet biomass stream.« less

Temporal measurements and kinetics of selenium release during coal combustion and gasification in a fluidized bed.

PubMed

Shen, Fenghua; Liu, Jing; Zhang, Zhen; Yang, Yingju

2016-06-05

The temporal release of selenium from coal during combustion and gasification in a fluidized bed was measured in situ by an on-line analysis system of trace elements in flue gas. The on-line analysis system is based on an inductively coupled plasma optical emission spectroscopy (ICP-OES), and can measure concentrations of trace elements in flue gas quantitatively and continuously. The results of on-line analysis suggest that the concentration of selenium in flue gas during coal gasification is higher than that during coal combustion. Based on the results of on-line analysis, a second-order kinetic law r(x)=0.94e(-26.58/RT)(-0.56 x(2) -0.51 x+1.05) was determined for selenium release during coal combustion, and r(x)=11.96e(-45.03/RT)(-0.53 x(2) -0.56 x+1.09) for selenium release during coal gasification. These two kinetic laws can predict respectively the temporal release of selenium during coal combustion and gasification with an acceptable accuracy. Thermodynamic calculations were conducted to predict selenium species during coal combustion and gasification. The speciation of selenium in flue gas during coal combustion differs from that during coal gasification, indicating that selenium volatilization is different. The gaseous selenium species can react with CaO during coal combustion, but it is not likely to interact with mineral during coal gasification. Copyright © 2016 Elsevier B.V. All rights reserved.

Data summary of municipal solid waste management alternatives. Volume 12, Numerically indexed bibliography

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1992-10-01

This appendix contains the numerically indexed bibliography for the complete group of reports on municipal solid waste management alternatives. The list references information on the following topics: mass burn technologies, RDF technologies, fluidized bed combustion, pyrolysis and gasification of MSW, materials recovery- recycling technologies, sanitary landfills, composting and anaerobic digestion of MSW.

Data summary of municipal solid waste management alternatives. Volume 11, Alphabetically indexed bibliography

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1992-10-01

This appendix contains the alphabetically indexed bibliography for the complete group of reports on municipal waste management alternatives. The references are listed for each of the following topics: mass burn technologies, RDF technologies, fluidized-bed combustion, pyrolysis and gasification of MSW, materials recovery- recycling technologies, sanitary landfills, composting, and anaerobic digestion of MSW.

Evaluation of wood chip gasification to produce reburn fuel for coal-fired boilers

EPA Science Inventory

Gasification/reburn testing with biomass and other wastes is of interest to both the U.S. Environmental Protection Agency (EPA) and the Italian Ministry of the Environment & Territory (IMET). Gasification systems that use wastes as feedstock should provide a clean, efficient sour...

Improved catalysts for carbon and coal gasification

DOEpatents

McKee, D.W.; Spiro, C.L.; Kosky, P.G.

1984-05-25

This invention relates to improved catalysts for carbon and coal gasification and improved processes for catalytic coal gasification for the production of methane. The catalyst is composed of at least two alkali metal salts and a particulate carbonaceous substrate or carrier is used. 10 figures, 2 tables.

BIOMASS REACTIVITY IN GASIFICATION BY THE HYNOL PROCESS

EPA Science Inventory

A thermobalance reactor was used to evaluate the reactivity of poplar wood in gasification under the operating conditions specific for the Hynol process where biomass is gasified at 30 atm and 800E C with a hydrogen-rich gas recycled from methane synthesis. The gasification invol...

Methods for sequestering carbon dioxide into alcohols via gasification fermentation

DOEpatents

Gaddy, James L; Ko, Ching-Whan; Phillips, J. Randy; Slape, M. Sean

2013-11-26

The present invention is directed to improvements in gasification for use with synthesis gas fermentation. Further, the present invention is directed to improvements in gasification for the production of alcohols from a gaseous substrate containing at least one reducing gas containing at least one microorganism.

Interdisciplinary research and development on the effects of the nature and properties of ceramic materials in the design of advanced structural components

NASA Technical Reports Server (NTRS)

1978-01-01

An educational development and supportive research program on ceramic materials established to advance design methodology, improve materials, and develop engineers knowledgable in design with and use of high performance ceramic materials is described. Emphasis is on the structures and related materials problems in a ceramic turbine engine, but applications in coal gasification, solar conversion, and magnetohydrodynamic technologies are considered. Progress of various research projects in the areas of new materials, processing, characterization, and nondestructive testing is reported. Fracture toughness determination, extended X-ray absorption fine structure measurements, and grain boundary effects in beta-alumina are among the topics covered.

Development of a Model for the Heat Release Rate of Wood. A Status Report.

DTIC Science & Technology

1985-05-01

K) *contraction factor L effective heat of gasification (kJ/kg) (positive) Lv latent heat of vaporization of water (kJ/kg) (positive) m mass (kg) M...designates the slice bounded by the rear surface 0 ambient or original *0 oxygen R radiation rel release S front surface of specimen Vol volatiles ix w water ...calorimeter. Along the other pathway, char is formed with the release of water and other volatiles having low heats of combustion. The effective heat of

Evaluation of Biomass Gasification to Produce Reburning Fuel for Coal-Fired Boilers

EPA Science Inventory

Gasification and reburning testing with biomass and other wastes is of interest to both the U.S. EPA and the Italian Ministry of the Environment & Territory. Gasification systems that use biofuels or wastes as feedstock can provide a clean, efficient source of synthesis gas and p...

Evaluation of wood chip gasification to produce reburrn fuel for coal-fired boilers: AWMA

EPA Science Inventory

Gasification or reburn testing with biomass and other wastes is of interest to both the U.S. Environmental Protection Agency (EPA) and the Italian Ministry of the Environment & Territory (IMET). Gasification systems that use wastes as feedstock should provide a clean, efficient s...

Modeling integrated biomass gasification business concepts

Treesearch

Peter J. Ince; Ted Bilek; Mark A. Dietenberger

2011-01-01

Biomass gasification is an approach to producing energy and/or biofuels that could be integrated into existing forest product production facilities, particularly at pulp mills. Existing process heat and power loads tend to favor integration at existing pulp mills. This paper describes a generic modeling system for evaluating integrated biomass gasification business...

Method for in situ gasification of a subterranean coal bed

DOEpatents

Shuck, Lowell Z.

1977-05-31

The method of the present invention relates to providing controlled directional bores in subterranean earth formations, especially coal beds for facilitating in situ gasification operations. Boreholes penetrating the coal beds are interconnected by laser-drilled bores disposed in various arrays at selected angles to the major permeability direction in the coal bed. These laser-drilled bores are enlarged by fracturing prior to the gasification of the coal bed to facilitate the establishing of combustion zones of selected configurations in the coal bed for maximizing the efficiency of the gasification operation.

The role of high-Btu coal gasification technology

NASA Astrophysics Data System (ADS)

German, M. I.

An analysis is given of the role and economic potential of Lurgi-technology gasification of coal to the year 2000, in relation to other gas-supply options, the further development of gasifier designs, and probable environmental impact. It is predicted that coal gasification may reach 10% of total gas supplies by the year 2000, with Eastern U.S. coal use reaching commercially significant use in the 1990's. It is concluded that coal gasification is the cleanest way of using coal, with minimal physical, chemical, biological and socioeconomic impacts.

Recent regulatory experience of low-Btu coal gasification. Volume III. Supporting case studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ackerman, E.; Hart, D.; Lethi, M.

The MITRE Corporation conducted a five-month study for the Office of Resource Applications in the Department of Energy on the regulatory requirements of low-Btu coal gasification. During this study, MITRE interviewed representatives of five current low-Btu coal gasification projects and regulatory agencies in five states. From these interviews, MITRE has sought the experience of current low-Btu coal gasification users in order to recommend actions to improve the regulatory process. This report is the third of three volumes. It contains the results of interviews conducted for each of the case studies. Volume 1 of the report contains the analysis of themore » case studies and recommendations to potential industrial users of low-Btu coal gasification. Volume 2 contains recommendations to regulatory agencies.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Overend, R.P.; Rivard, C.J.

Gasification is being developed to enable a diverse range of biomass resources to meet modern secondary energy uses, especially in the electrical utility sector. Biological or anaerobic gasification in US landfills has resulted in the installation of almost 500 MW(e) of capacity and represents the largest scale application of gasification technology today. The development of integrated gasification combined cycle generation for coal technologies is being paralleled by bagasse and wood thermal gasification systems in Hawaii and Scandinavia, and will lead to significant deployment in the next decade as the current scale-up activities are commercialized. The advantages of highly reactive biomassmore » over coal in the design of process units are being realized as new thermal gasifiers are being scaled up to produce medium-energy-content gas for conversion to synthetic natural gas and transportation fuels and to hydrogen for use in fuel cells. The advent of high solids anaerobic digestion reactors is leading to commercialization of controlled municipal solid waste biological gasification rather than landfill application. In both thermal and biological gasification, high rate process reactors are a necessary development for economic applications that address waste and residue management and the production and use of new crops for energy. The environmental contribution of biomass in reducing greenhouse gas emission will also be improved.« less

Integrated Biomass Gasification with Catalytic Partial Oxidation for Selective Tar Conversion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Lingzhi; Wei, Wei; Manke, Jeff

Biomass gasification is a flexible and efficient way of utilizing widely available domestic renewable resources. Syngas from biomass has the potential for biofuels production, which will enhance energy security and environmental benefits. Additionally, with the successful development of low Btu fuel engines (e.g. GE Jenbacher engines), syngas from biomass can be efficiently used for power/heat co-generation. However, biomass gasification has not been widely commercialized because of a number of technical/economic issues related to gasifier design and syngas cleanup. Biomass gasification, due to its scale limitation, cannot afford to use pure oxygen as the gasification agent that used in coal gasification.more » Because, it uses air instead of oxygen, the biomass gasification temperature is much lower than well-understood coal gasification. The low temperature leads to a lot of tar formation and the tar can gum up the downstream equipment. Thus, the biomass gasification tar removal is a critical technology challenge for all types of biomass gasifiers. This USDA/DOE funded program (award number: DE-FG36-O8GO18085) aims to develop an advanced catalytic tar conversion system that can economically and efficiently convert tar into useful light gases (such as syngas) for downstream fuel synthesis or power generation. This program has been executed by GE Global Research in Irvine, CA, in collaboration with Professor Lanny Schmidt's group at the University of Minnesota (UoMn). Biomass gasification produces a raw syngas stream containing H2, CO, CO2, H2O, CH4 and other hydrocarbons, tars, char, and ash. Tars are defined as organic compounds that are condensable at room temperature and are assumed to be largely aromatic. Downstream units in biomass gasification such as gas engine, turbine or fuel synthesis reactors require stringent control in syngas quality, especially tar content to avoid plugging (gum) of downstream equipment. Tar- and ash-free syngas streams are a critical requirement for commercial deployment of biomass-based power/heat co-generation and biofuels production. There are several commonly used syngas clean-up technologies: (1) Syngas cooling and water scrubbing has been commercially proven but efficiency is low and it is only effective at small scales. This route is accompanied with troublesome wastewater treatment. (2) The tar filtration method requires frequent filter replacement and solid residue treatment, leading to high operation and capital costs. (3) Thermal destruction typically operates at temperatures higher than 1000oC. It has slow kinetics and potential soot formation issues. The system is expensive and materials are not reliable at high temperatures. (4) In-bed cracking catalysts show rapid deactivation, with durability to be demonstrated. (5) External catalytic cracking or steam reforming has low thermal efficiency and is faced with problematic catalyst coking. Under this program, catalytic partial oxidation (CPO) is being evaluated for syngas tar clean-up in biomass gasification. The CPO reaction is exothermic, implying that no external heat is needed and the system is of high thermal efficiency. CPO is capable of processing large gas volume, indicating a very compact catalyst bed and a low reactor cost. Instead of traditional physical removal of tar, the CPO concept converts tar into useful light gases (eg. CO, H2, CH4). This eliminates waste treatment and disposal requirements. All those advantages make the CPO catalytic tar conversion system a viable solution for biomass gasification downstream gas clean-up. This program was conducted from October 1 2008 to February 28 2011 and divided into five major tasks. - Task A: Perform conceptual design and conduct preliminary system and economic analysis (Q1 2009 ~ Q2 2009) - Task B: Biomass gasification tests, product characterization, and CPO tar conversion catalyst preparation. This task will be conducted after completing process design and system economics analysis. Major milestones include identification of syngas cleaning requirements for proposed system design, identification and selection of tar compounds and 2 mixtures for use in CPO tests, and preparation of CPO catalysts for validation. (Q3 2009 ~ Q4 2009) - Task C: Test CPO with biomass gasification product gas. Optimize CPO performance with selected tar compounds. Optimize CPO performance with multi-component mixtures. Milestones include optimizing CPO catalysts design, collecting CPO experimental data for next stage kinetic modeling and understanding the effect of relative reactivities on ultimate tar conversion and syngas yields. (Q1 2010 ~ Q3 2010) - Task D: Develop tar CPO kinetic model with CPO kinetic model and modeling results as deliverables. (Q3 2010 ~ Q2 2011) - Task E: Project management and reporting. Milestone: Quarterly reports and presentations, final report, work presented at national technical conferences (Q1 2009 ~ Q2 2011) At the beginning of the program, IP landscaping was conducted to understand the operation of various types of biomass gasifiers, their unique syngas/tar compositions and potential tar mitigation options using the catalytic partial oxidation technology. A process simulation model was developed to quantify the system performance and economics impact of CPO tar removal technology. Biomass gasification product compositions used for performance evaluation tests were identified after literature review and system modeling. A reaction system for tar conversion tests was designed, constructed, with each individual component shaken-down in 2009. In parallel, University of Minnesota built a lab-scale unit and evaluated the tar removal performance using catalytic reforming. Benzene was used as the surrogate compound. The biomass gasification raw syngas composition was provided by GE through system studies. In 2010, GE selected different tar compounds and evaluated the tar removal effectiveness of the CPO catalyst. The catalytic performance was evaluated under different operating conditions, including catalyst geometry, S/C ratio, O/C ratio, GHSV, and N2 dilution. An understanding of how to optimize catalytic tar removal efficiency by varying operating conditions has been developed. GE collaborated with UoMn in examining inorganic impurities effects. Catalysts were pre-impregnated with inorganic impurities commonly present in biomass gasification syngas, including Si, Ca, Mg, Na, K, P and S. UoMn performed catalyst characterization and has acquired fundamental understandings of impurities effect on catalytic tar removal. Based on experimental data and the proposed reaction pathway, GE constructed a model to predict kinetic performance for biomass gasification tar cleanup process. Experimental data (eg. tar conversion, reactor inlet and outlet temperatures, product distribution) at different operating conditions were used to validate the model. A good fit between model predictions and experimental data was found. This model will be a valuable tool in designing the tar removal reactor and identifying appropriate operating conditions. We attended the 2011 DOE Biomass Program Thermochemical Platform Review held in Denver, CO from February 16 to 18 and received very positive comments from the review panel. Further, syngas utility and biomass to power/fuel companies expressed strong interest in our tar removal technology.« less

Non-slag co-gasification of biomass and coal in entrained-bed furnace

NASA Astrophysics Data System (ADS)

Itaya, Yoshinori; Suami, Akira; Kobayashi, Nobusuke

2018-02-01

Gasification is a promising candidate of processes to upgrade biomass and to yield clean gaseous fuel for utilization of renewable energy resources. However, a sufficient amount of biomass is not always available to operate a large scale of the plant. Co-gasification of biomass with coal is proposed as a solution of the problem. Tar emission is another subject during operation in shaft or kiln type of gasifiers employed conventionally for biomass. The present authors proposed co-gasification of biomass and coal in entrained-bed furnace, which is a representative process without tar emission under high temperature, but operated so to collect dust as flyash without molten slag formation. This paper presents the works performed on co-gasification performance of biomass and pulverized coal to apply to entrained-bed type of furnaces. At first, co-gasification of woody powder and pulverized coal examined using the lab-scale test furnace of the down-flow entrained bed showed that the maximum temperatures in the furnace was over 1500 K and the carbon conversion to gas achieved at higher efficiency than 80-90 percent although the residence time in the furnace was as short as a few seconds. Non-slag co-gasification was carried out successfully without slag formation in the furnace if coal containing ash with high fusion temperature was employed. The trend suggesting the effect of reaction rate enhancement of co-gasification was also observed. Secondary, an innovative sewage sludge upgrading system consisting of self-energy recovery processes was proposed to yield bio-dried sludge and to sequentially produce char without adding auxiliary fuel. Carbonization behavior of bio-dried sludge was evaluated through pyrolysis examination in a lab-scale quartz tube reactor. The thermal treatment of pyrolysis of sludge contributed to decomposition and removal of contaminant components such as nitrogen and sulfur. The gasification kinetics of sludge and coal was also determined by a thermogravimetric analysis. It was revealed that co-gasification rate of sludge and coal chars was influenced negatively due to high ash content in sludge.

Coal Gasification - section in Kirk-Othmer Concise Encyclopedia of Chemical Technology, 5th Edition, 2-vol. set, July 2007, ISBN 978-0-470-04748-4, pp. 580-587

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shadle, L.J.; Berry, D.A.; Syamlal, Madhava

2007-07-01

Coal gasification is the process of reacting coal with oxygen, steam, and carbon dioxide to form a product gas containing hydrogen and carbon monoxide. Gasification is essentially incomplete combustion. The chemical and physical processes are quite similar, the main difference being the nature of the final products. From a processing point of view the main operating difference is that gasification consumes heat evolved during combustion. Under the reducing environment of gasification the sulfur in the coal is released as hydrogen sulfide rather than sulfur dioxide and the coal's nitrogen is converted mostly to ammonia rather than nitrogen oxides. These reducedmore » forms of sulfur and nitrogen are easily isolated, captured, and utilized, and thus gasification is a clean coal technology with better environmental performance than coal combustion. Depending on the type of gasifier and the operating conditions, gasification can be used to produce a fuel gas suitable for any number of applications. A low heating value fuel gas is produced from an air blown gasifier for use as an industrial fuel and for power production. A medium heating value fuel gas is produced from enriched oxygen blown gasification for use as a synthesis gas in the production of chemicals such as ammonia, methanol, and transportation fuels. A high heating value gas can be produced from shifting the medium heating value product gas over catalysts to produce a substitute or synthetic natural gas (SNG).« less

Advanced treatment of biologically pretreated coal gasification wastewater by a novel integration of heterogeneous Fenton oxidation and biological process.

PubMed

Xu, Peng; Han, Hongjun; Zhuang, Haifeng; Hou, Baolin; Jia, Shengyong; Xu, Chunyan; Wang, Dexin

2015-04-01

Laboratorial scale experiments were conducted in order to investigate a novel system integrating heterogeneous Fenton oxidation (HFO) with anoxic moving bed biofilm reactor (ANMBBR) and biological aerated filter (BAF) process on advanced treatment of biologically pretreated coal gasification wastewater (CGW). The results indicated that HFO with the prepared catalyst (FeOx/SBAC, sewage sludge based activated carbon (SBAC) which loaded Fe oxides) played a key role in eliminating COD and COLOR as well as in improving the biodegradability of raw wastewater. The surface reaction and hydroxyl radicals (OH) oxidation were the mechanisms for FeOx/SBAC catalytic reaction. Compared with ANMBBR-BAF process, the integrated system was more effective in abating COD, BOD5, total phenols (TPs), total nitrogen (TN) and COLOR and could shorten the retention time. Therefore, the integrated system was a promising technology for engineering applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

Producer gas production of Indonesian biomass in fixed-bed downdraft gasifier as an alternative fuels for internal combustion engines

NASA Astrophysics Data System (ADS)

Simanjuntak, J. P.; Lisyanto; Daryanto, E.; Tambunan, B. H.

2018-03-01

downdraft biomass gasification reactors, coupled with reciprocating internal combustion engines (ICE) are a viable technology for small scale heat and power generation. The direct use of producer gas as fuel subtitution in an ICE could be of great interest since Indonesia has significant land area in different forest types that could be used to produce bioenergy and convert forest materials to bioenergy for use in energy production and the versatility of this engine. This paper will look into the aspect of biomass energie as a contributor to energy mix in Indonesia. This work also contains information gathered from numerous previews study on the downdraft gasifier based on experimental or simulation study on the ability of producer gas as fuels for internal combustion engines aplication. All data will be used to complement the preliminary work on biomass gasification using downdraft to produce producer gas and its application to engines.

Coal: the new black

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tullo, A.H.; Tremblay, J.-F.

2008-03-15

Long eclipsed by oil and natural gas as a raw material for high-volume chemicals, coal is making a comeback, with oil priced at more than $100 per barrel. It is relatively cheap feedstock for chemicals such as methanol and China is building plants to convert coal to polyolefins on a large scale and interest is spreading worldwide. Over the years several companies in the US and China have made fertilizers via the gasification of coal. Eastman in Tennessee gasifies coal to make methanol which is then converted to acetic acid, acetic anhydride and acetate fiber. The future vision is tomore » convert methanol to olefins. UOP and Lurgi are the major vendors of this technology. These companies are the respective chemical engineering arms of Honeywell and Air Liquide. The article reports developments in China, USA and India on coal-to-chemicals via coal gasification or coal liquefaction. 2 figs., 2 photo.« less

Comparative study of thermochemical processes for hydrogen production from biomass fuels.

PubMed

Biagini, Enrico; Masoni, Lorenzo; Tognotti, Leonardo

2010-08-01

Different thermochemical configurations (gasification, combustion, electrolysis and syngas separation) are studied for producing hydrogen from biomass fuels. The aim is to provide data for the production unit and the following optimization of the "hydrogen chain" (from energy source selection to hydrogen utilization) in the frame of the Italian project "Filiera Idrogeno". The project focuses on a regional scale (Tuscany, Italy), renewable energies and automotive hydrogen. Decentred and small production plants are required to solve the logistic problems of biomass supply and meet the limited hydrogen infrastructures. Different options (gasification with air, oxygen or steam/oxygen mixtures, combustion, electrolysis) and conditions (varying the ratios of biomass and gas input) are studied by developing process models with uniform hypothesis to compare the results. Results obtained in this work concern the operating parameters, process efficiencies, material and energetic needs and are fundamental to optimize the entire hydrogen chain. Copyright 2010 Elsevier Ltd. All rights reserved.

Development of Improved Iron-Aluminide Filter Tubes and Elements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Judkins, R.R.; Sutton, T.G.; Miller, C.J.

2008-01-14

The purpose of this Cooperative Research and Development Agreement (CRADA) was to explore and develop advanced manufacturing techniques to fabricate sintered iron-aluminide intermetallic porous bodies used for gas filtration so as to reduce production costs while maintaining or improving performance in advanced coal gasification and combustion systems. The use of a power turbine fired with coal-derived synthesis gas requires some form of gas cleaning in order to protect turbine and downstream components from degradation by erosion, corrosion, and/or deposition. Hot-gas filtration is one form of cleaning that offers the ability to remove particles from the gases produced by gasification processesmore » without having to substantially cool and, possibly, reheat them before their introduction into the turbine. This technology depends critically on materials durability and reliability, which have been the subject of study for a number of years.« less

Vision of the U.S. biofuel future: a case for hydrogen-enriched biomass gasification

Treesearch

Mark A. Dietenberger; Mark Anderson

2007-01-01

Researchers at the Forest Product Laboratory (FPL) and the University of Wisconsin-Madison (UW) envision a future for biofuels based on biomass gasification with hydrogen enrichment. Synergisms between hydrogen production and biomass gasification technologies will be necessary to avoid being marginalized in the biofuel marketplace. Five feasible engineering solutions...

Experimental Studies of Coal and Biomass Fuel Synthesis and Flame Characterization for Aircraft Engines

DTIC Science & Technology

2012-03-31

there is a need for fundamental scientific and synergistic research in catalytic biomass fast-hydropyrolysis and advanced coal gasification studies...produce appropriate aviation fuels. 15. SUBJECT TERMS Biomass fast hydropyrolysis, hydrodeoxygenation, and coal gasification 16. SECURITY...22 2.0 Investigation of Coal and Biomass Gasification using In-situ

Countercurrent fixed-bed gasification of biomass at laboratory scale

DOE Office of Scientific and Technical Information (OSTI.GOV)

Di Blasi, C.; Signorelli, G.; Portoricco, G.

1999-07-01

A laboratory-scale countercurrent fixed-bed gasification plant has been designed and constructed to produce data for process modeling and to compare the gasification characteristics of several biomasses (beechwood, nutshells, olive husks, and grape residues). The composition of producer gas and spatial temperature profiles have been measured for biomass gasification at different air flow rates. The gas-heating value always attains a maximum as a function of this operating variable, associated with a decrease of the air-to-fuel ratio. Optical gasification conditions of wood and agricultural residues give rise to comparable gas-heating values, comprised in the range 5--5.5 MJ/Nm{sup 3} with 28--30% CO, 5--7%more » CO{sub 2}, 6--8% H{sub 2}, 1--2% CH{sub 4}, and small amounts of C{sub 2}- hydrocarbons (apart from nitrogen). However, gasification of agricultural residues is more difficult because of bed transport, partial ash sintering, nonuniform flow distribution, and the presence of a muddy phase in the effluents, so that proper pretreatments are needed for largescale applications.« less

Combustion and gasification characteristics of chars from four commercially significant coals of different rank. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nsakala, N.Y.; Patel, R.L.; Lao, T.C.

1982-09-01

The combustion and gasification kinetics of four size graded coal chars were investigated experimentally in Combustion Engineering's Drop Tube Furnace System (DTFS). The chars were prepared in the DTFS from commercially significant coals representing a wide range of rank; these included a Pittsburgh No. 8 Seam hvAb coal, an Illinois No. 6 Seam hvCb coal, a Wyoming Sub C, and a Texas Lignite A. Additionally, a number of standard ASTM and special bench scale tests were performed on the coals and chars to characterize their physicochemical properties. Results showed that the lower rank coal chars were more reactive than themore » higher rank coal chars and that combustion reactions of chars were much faster than the corresponding gasification reactions. Fuel properties, temperature, and reactant gas partial pressure had a significant influence on both combustion and gasification, and particle size had a mild but discernible influence on gasification. Fuel reactivities were closely related to pore structure. Computer simulation of the combustion and gasification performances of the subject samples in the DTFS supported the experimental findings.« less

Co-gasification of biosolids with biomass: Thermogravimetric analysis and pilot scale study in a bubbling fluidized bed reactor.

PubMed

Yu, Ming Ming; Masnadi, Mohammad S; Grace, John R; Bi, Xiaotao T; Lim, C Jim; Li, Yonghua

2015-01-01

This work studied the feasibility of co-gasification of biosolids with biomass as a means of disposal with energy recovery. The kinetics study at 800°C showed that biomass, such as switchgrass, could catalyze the reactions because switchgrass ash contained a high proportion of potassium, an excellent catalyst for gasification. However, biosolids could also inhibit gasification due to interaction between biomass alkali/alkaline earth metals and biosolids clay minerals. In the pilot scale experiments, increasing the proportion of biosolids in the feedstock affected gasification performance negatively. Syngas yield and char conversion decreased from 1.38 to 0.47m(3)/kg and 82-36% respectively as the biosolids proportion in the fuel increased from 0% to 100%. Over the same range, the tar content increased from 10.3 to 200g/m(3), while the ammonia concentration increased from 1660 to 19,200ppmv. No more than 25% biosolids in the fuel feed is recommended to maintain a reasonable gasification. Copyright © 2014 Elsevier Ltd. All rights reserved.

Gasification of palm empty fruit bunch in a bubbling fluidized bed: a performance and agglomeration study.

PubMed

Lahijani, Pooya; Zainal, Zainal Alimuddin

2011-01-01

Gasification of palm empty fruit bunch (EFB) was investigated in a pilot-scale air-blown fluidized bed. The effect of bed temperature (650-1050 °C) on gasification performance was studied. To explore the potential of EFB, the gasification results were compared to that of sawdust. Results showed that maximum heating values (HHV) of 5.37 and 5.88 (MJ/Nm3), dry gas yield of 2.04 and 2.0 (Nm3/kg), carbon conversion of 93% and 85 % and cold gas efficiency of 72% and 71 % were obtained for EFB and sawdust at the temperature of 1050 °C and ER of 0.25. However, it was realized that agglomeration was the major issue in EFB gasification at high temperatures. To prevent the bed agglomeration, EFB gasification was performed at temperature of 770±20 °C while the ER was varied from 0.17 to 0.32. Maximum HHV of 4.53 was obtained at ER of 0.21 where no agglomeration was observed. Copyright © 2010 Elsevier Ltd. All rights reserved.

CO2 co-gasification of lower sulphur petroleum coke and sugar cane bagasse via TG-FTIR analysis technique.

PubMed

Edreis, Elbager M A; Luo, Guangqian; Li, Aijun; Chao, Chen; Hu, Hongyun; Zhang, Sen; Gui, Ben; Xiao, Li; Xu, Kai; Zhang, Pingan; Yao, Hong

2013-05-01

This study investigates the non-isothermal mechanism and kinetic behaviour of gasification of a lower sulphur petroleum coke, sugar cane bagasse and blends under carbon dioxide atmosphere conditions using the thermogravimetric analyser (TGA). The gas products were measured online with coupled Fourier transform infrared spectroscopy (FTIR). The achieved results explored that the sugar cane bagasse and blend gasification happened in two steps: at (<500 °C) the volatiles are released, and at (>700 °C) char gasification occurred, whereas the lower sulphur petroleum coke presented only one char gasification stage at (>800 °C). Significant interactions were observed in the whole process. Some solid-state mechanisms were studied by the Coats-Redfern method in order to observe the mechanisms responsible for the gasification of samples. The results show that the chemical first order reaction is the best responsible mechanism for whole process. The main released gases are CO2, CO, CH4, HCOOH, C6H5OH and CH3COOH. Copyright © 2013 Elsevier Ltd. All rights reserved.

Influence of the reactant carbon-hydrogen-oxygen composition on the key products of the direct gasification of dewatered sewage sludge in supercritical water.

PubMed

Gong, Miao; Zhu, Wei; Fan, Yujie; Zhang, Huiwen; Su, Ying

2016-05-01

The supercritical water gasification of ten different types of dewatered sewage sludges was investigated to understand the relationship between sludge properties and gasification products. Experiments were performed in a high-pressure autoclave at 400°C for 60 min. Results showed that gasification of sewage sludge in supercritical water consists mainly of a gasification reaction, a carbonization reaction and a persistent organic pollutants synthesis reaction. Changes in the reactant C/H/O composition have significant effects on the key gasification products. Total gas production increased with increasing C/H2O of the reactant. The char/coke content increased with increasing C/H ratio of the reactant. A decrease in the C/O ratio of the reactant led to a reduction in polycyclic aromatic hydrocarbon formation. This means that we can adjust the reactant C/H/O composition by adding carbon-, hydrogen-, and oxygen-containing substances such as coal, algae and H2O2 to optimize hydrogen production and to inhibit an undesired by-product formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Co-gasification of tire and biomass for enhancement of tire-char reactivity in CO2 gasification process.

PubMed

Lahijani, Pooya; Zainal, Zainal Alimuddin; Mohamed, Abdul Rahman; Mohammadi, Maedeh

2013-06-01

In this investigation, palm empty fruit bunch (EFB) and almond shell (AS) were implemented as two natural catalysts rich in alkali metals, especially potassium, to enhance the reactivity of tire-char through co-gasification process. Co-gasification experiments were conducted at several blending ratios using isothermal Thermogravimetric analysis (TGA) under CO2. The pronounced effect of inherent alkali content of biomass-chars on promoting the reactivity of tire-char was proven when acid-treated biomass-chars did not exert any catalytic effect on improving the reactivity of tire-char in co-gasification experiments. In kinetic studies of the co-gasified samples in chemically-controlled regime, modified random pore model (M-RPM) was adopted to describe the reactive behavior of the tire-char/biomass-char blends. By virtue of the catalytic effect of biomass, the activation energy for tire-char gasification was lowered from 250 kJ/mol in pure form 203 to 187 kJ/mol for AS-char and EFB-char co-gasified samples, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

Taguchi approach for co-gasification optimization of torrefied biomass and coal.

PubMed

Chen, Wei-Hsin; Chen, Chih-Jung; Hung, Chen-I

2013-09-01

This study employs the Taguchi method to approach the optimum co-gasification operation of torrefied biomass (eucalyptus) and coal in an entrained flow gasifier. The cold gas efficiency is adopted as the performance index of co-gasification. The influences of six parameters, namely, the biomass blending ratio, oxygen-to-fuel mass ratio (O/F ratio), biomass torrefaction temperature, gasification pressure, steam-to-fuel mass ratio (S/F ratio), and inlet temperature of the carrier gas, on the performance of co-gasification are considered. The analysis of the signal-to-noise ratio suggests that the O/F ratio is the most important factor in determining the performance and the appropriate O/F ratio is 0.7. The performance is also significantly affected by biomass along with torrefaction, where a torrefaction temperature of 300°C is sufficient to upgrade eucalyptus. According to the recommended operating conditions, the values of cold gas efficiency and carbon conversion at the optimum co-gasification are 80.99% and 94.51%, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

Co-gasification of coal and biomass: Synergy, characterization and reactivity of the residual char.

PubMed

Hu, Junhao; Shao, Jingai; Yang, Haiping; Lin, Guiying; Chen, Yingquan; Wang, Xianhua; Zhang, Wennan; Chen, Hanping

2017-11-01

The synergy effect between coal and biomass in their co-gasification was studied in a vertical fixed bed reactor, and the physic-chemical structural characteristics and gasification reactivity of the residual char obtained from co-gasification were also investigated. The results shows that, conversion of the residual char and tar into gas is enhanced due to the synergy effect between coal and biomass. The physical structure of residual char shows more pore on coal char when more biomass is added in the co-gasification. The migration of inorganic elements between coal and biomass was found, the formation and competitive role of K 2 SiO 3 , KAlSiO 4 , and Ca 3 Al 2 (SiO 4 ) 3 is a mechanism behind the synergy. The graphization degree is enhanced but size of graphite crystallite in the residual char decreases with biomass blending ratio increasing. TGA results strongly suggest the big difference in the reactivity of chars derived from coal and biomass in spite of influence from co-gasification. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ab initio calculations and kinetic modeling of thermal conversion of methyl chloride: implications for gasification of biomass.

PubMed

Singla, Mallika; Rasmussen, Morten Lund; Hashemi, Hamid; Wu, Hao; Glarborg, Peter; Pelucchi, Matteo; Faravelli, Tiziano; Marshall, Paul

2018-04-25

Limitations in current hot gas cleaning methods for chlorine species from biomass gasification may be a challenge for end use such as gas turbines, engines, and fuel cells, all requiring very low levels of chlorine. During devolatilization of biomass, chlorine is released partly as methyl chloride. In the present work, the thermal conversion of CH3Cl under gasification conditions was investigated. A detailed chemical kinetic model for pyrolysis and oxidation of methyl chloride was developed and validated against selected experimental data from the literature. Key reactions of CH2Cl with O2 and C2H4 for which data are scarce were studied by ab initio methods. The model was used to analyze the fate of methyl chloride in gasification processes. The results indicate that CH3Cl emissions will be negligible for most gasification technologies, but could be a concern for fluidized bed gasifiers, in particular in low-temperature gasification. The present work illustrates how ab initio theory and chemical kinetic modeling can help to resolve emission issues for thermal processes in industrial scale.

Gas processing handbook

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1982-04-01

Brief details are given of processes including: BGC-Lurgi slagging gasification, COGAS, Exxon catalytic coal gasification, FW-Stoic 2-stage, GI two stage, HYGAS, Koppers-Totzek, Lurgi pressure gasification, Saarberg-Otto, Shell, Texaco, U-Gas, W-D.IGI, Wellman-Galusha, Westinghouse, and Winkler coal gasification processes; the Rectisol process; the Catacarb and the Benfield processes for removing CO/SUB/2, H/SUB/2s and COS from gases produced by the partial oxidation of coal; the selectamine DD, Selexol solvent, and Sulfinol gas cleaning processes; the sulphur-tolerant shift (SSK) process; and the Super-meth process for the production of high-Btu gas from synthesis gas.

Method and system for controlling a gasification or partial oxidation process

DOEpatents

Rozelle, Peter L; Der, Victor K

2015-02-10

A method and system for controlling a fuel gasification system includes optimizing a conversion of solid components in the fuel to gaseous fuel components, controlling the flux of solids entrained in the product gas through equipment downstream of the gasifier, and maximizing the overall efficiencies of processes utilizing gasification. A combination of models, when utilized together, can be integrated with existing plant control systems and operating procedures and employed to develop new control systems and operating procedures. Such an approach is further applicable to gasification systems that utilize both dry feed and slurry feed.

Integration of stripping of fines slurry in a coking and gasification process

DOEpatents

DeGeorge, Charles W.

1980-01-01

In an integrated fluid coking and gasification process wherein a stream of fluidized solids is passed from a fluidized bed coking zone to a second fluidized bed and wherein entrained solid fines are recovered by a wet scrubbing process and wherein the resulting solids-liquid slurry is stripped to remove acidic gases, the stripped vapors of the stripping zone are sent to the gas cleanup stage of the gasification product gas. The improved stripping integration is particularly useful in the combination coal liquefaction process, fluid coking of bottoms of the coal liquefaction zone and gasification of the product coke.

Fluidized-bed catalytic coal-gasification process. [US patent; pretreatment to minimize agglomeration

DOEpatents

Euker, C.A. Jr.; Wesselhoft, R.D.; Dunkleman, J.J.; Aquino, D.C.; Gouker, T.R.

1981-09-14

Coal or similar carbonaceous solids impregnated with gasification catalyst constituents are oxidized by contact with a gas containing between 2 vol % and 21 vol % oxygen at a temperature between 50 and 250/sup 0/C in an oxidation zone and the resultant oxidized, catalyst impregnated solids are then gasified in a fluidized bed gasification zone at an elevated pressure. The oxidation of the catalyst impregnated solids under these conditions insures that the bed density in the fluidized bed gasification zone will be relatively high even though the solids are gasified at elevated pressure and temperature.

Modular Biopower System Providing Combined Heat and Power for DoD Installations

DTIC Science & Technology

2013-12-01

ISSUES ......................................................................................... 41 8.4 GASIFIER SHELL INTEGRITY...review of DoD installations revealed that 170 of them had access to significant amounts of woody biomass materials within a 25-mile radius and an...DESCRIPTION The technology uses a downdraft gasification process to convert the energy trapped in biomass into a synthesis gas that is cooled, filtered

Two-stage coal gasification and desulfurization apparatus

DOEpatents

Bissett, Larry A.; Strickland, Larry D.

1991-01-01

The present invention is directed to a system which effectively integrates a two-stage, fixed-bed coal gasification arrangement with hot fuel gas desulfurization of a first stream of fuel gas from a lower stage of the two-stage gasifier and the removal of sulfur from the sulfur sorbent regeneration gas utilized in the fuel-gas desulfurization process by burning a second stream of fuel gas from the upper stage of the gasifier in a combustion device in the presence of calcium-containing material. The second stream of fuel gas is taken from above the fixed bed in the coal gasifier and is laden with ammonia, tar and sulfur values. This second stream of fuel gas is burned in the presence of excess air to provide heat energy sufficient to effect a calcium-sulfur compound forming reaction between the calcium-containing material and sulfur values carried by the regeneration gas and the second stream of fuel gas. Any ammonia values present in the fuel gas are decomposed during the combustion of the fuel gas in the combustion chamber. The substantially sulfur-free products of combustion may then be combined with the desulfurized fuel gas for providing a combustible fluid utilized for driving a prime mover.

Leaching behaviour of bottom ash from RDF high-temperature gasification plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gori, M., E-mail: manuela.gori@dicea.unifi.it; Pifferi, L.; Sirini, P.

2011-07-15

This study investigated the physical properties, the chemical composition and the leaching behaviour of two bottom ash (BA) samples from two different refuse derived fuel high-temperature gasification plants, as a function of particle size. The X-ray diffraction patterns showed that the materials contained large amounts of glass. This aspect was also confirmed by the results of availability and ANC leaching tests. Chemical composition indicated that Fe, Mn, Cu and Cr were the most abundant metals, with a slight enrichment in the finest fractions. Suitability of samples for inert waste landfilling and reuse was evaluated through the leaching test EN 12457-2.more » In one sample the concentration of all metals was below the limit set by law, while limits were exceeded for Cu, Cr and Ni in the other sample, where the finest fraction showed to give the main contribution to leaching of Cu and Ni. Preliminary results of physical and geotechnical characterisation indicated the suitability of vitrified BA for reuse in the field of civil engineering. The possible application of a size separation pre-treatment in order to improve the chemical characteristics of the materials was also discussed.« less

Environmentally sustainable production of food, feed and fuel from natural resources in the tropics.

PubMed

Preston, T Reg

2009-08-01

Responding to the challenges posed by global warming, peak oil and biofuels will require a paradigm shift in the practice of agriculture and in the role of live stock within the farming system. Farming systems should aim at maximizing plant biomass production from locally available diversified resources, processing of the biomass on farm to provide food, feed and energy and recycling of all waste materials. The approach that is the subject of this paper is that the generation of electricity can be a by-product of food/feed production. The concept is the fractionation of biomass into inedible cell wall material that can be converted to an inflammable gas by gasification, the gas in turn being the source of fuel for internal combustion engines driving electrical generators. The cell contents and related structures such as tree leaves are used as human food or animal feed. As well as providing food and feed the model is highly appropriate for decentralized small scale production of electricity in rural areas. It also offers opportunities for sequestration of carbon in the form of biochar the solid residue remaining after gasification of the biomass.

Investigation of Coal-biomass Catalytic Gasification using Experiments, Reaction Kinetics and Computational Fluid Dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Battaglia, Francine; Agblevor, Foster; Klein, Michael

A collaborative effort involving experiments, kinetic modeling, and computational fluid dynamics (CFD) was used to understand co-gasification of coal-biomass mixtures. The overall goal of the work was to determine the key reactive properties for coal-biomass mixed fuels. Sub-bituminous coal was mixed with biomass feedstocks to determine the fluidization and gasification characteristics of hybrid poplar wood, switchgrass and corn stover. It was found that corn stover and poplar wood were the best feedstocks to use with coal. The novel approach of this project was the use of a red mud catalyst to improve gasification and lower gasification temperatures. An important resultsmore » was the reduction of agglomeration of the biomass using the catalyst. An outcome of this work was the characterization of the chemical kinetics and reaction mechanisms of the co-gasification fuels, and the development of a set of models that can be integrated into other modeling environments. The multiphase flow code, MFIX, was used to simulate and predict the hydrodynamics and co-gasification, and results were validated with the experiments. The reaction kinetics modeling was used to develop a smaller set of reactions for tractable CFD calculations that represented the experiments. Finally, an efficient tool was developed, MCHARS, and coupled with MFIX to efficiently simulate the complex reaction kinetics.« less

Gasification Characteristics and Kinetics of Coke with Chlorine Addition

NASA Astrophysics Data System (ADS)

Wang, Cui; Zhang, Jianliang; Jiao, Kexin; Liu, Zhengjian; Chou, Kuochih

2017-10-01

The gasification process of metallurgical coke with 0, 1.122, 3.190, and 7.132 wt pct chlorine was investigated through thermogravimetric method from ambient temperature to 1593 K (1320 °C) in purified CO2 atmosphere. The variations in the temperature parameters that T i decreases gradually with increasing chlorine, T f and T max first decrease and then increase, but both in a downward trend indicated that the coke gasification process was catalyzed by the chlorine addition. Then the kinetic model of the chlorine-containing coke gasification was obtained through the advanced determination of the average apparent activation energy, the optimal reaction model, and the pre-exponential factor. The average apparent activation energies were 182.962, 118.525, 139.632, and 111.953 kJ/mol, respectively, which were in the same decreasing trend with the temperature parameters analyzed by the thermogravimetric method. It was also demonstrated that the coke gasification process was catalyzed by chlorine. The optimal kinetic model to describe the gasification process of chlorine-containing coke was the Šesták Berggren model using Málek's method, and the pre-exponential factors were 6.688 × 105, 2.786 × 103, 1.782 × 104, and 1.324 × 103 min-1, respectively. The predictions of chlorine-containing coke gasification from the Šesták Berggren model were well fitted with the experimental data.

New projects for CCGTs with coal gasification (Review)

NASA Astrophysics Data System (ADS)

Olkhovskii, G. G.

2016-10-01

Perspectives of using coal in combined-cycle gas turbine units (CCGTs), which are significantly more efficient than steam power plants, have been associated with preliminary coal gasification for a long time. Due to gasification, purification, and burning the resulting synthesis gas at an increased pressure, there is a possibility to intensify the processes occurring in them and reduce the size and mass of equipment. Physical heat evolving from gasification can be used without problems in the steam circuit of a CCGT. The downside of these opportunities is that the unit becomes more complex and expensive, and its competitiveness is affected, which was not achieved for CCGT power plants with coal gasification built in the 1990s. In recent years, based on the experience with these CCGTs, several powerful CCGTs of the next generation, which used higher-output and cost-effective gas-turbine plants (GTPs) and more advanced systems of gasification and purification of synthesis gas, were either built or designed. In a number of cases, the system of gasification includes devices of CO vapor reforming and removal of the emitted CO2 at a high pressure prior to fuel combustion. Gasifiers with air injection instead of oxygen injection, which is common in coal chemistry, also find application. In this case, the specific cost of the power station considerably decreases (by 15% and more). In units with air injection, up to 40% air required for separation is drawn from the intermediate stage of the cycle compressor. The range of gasified coals has broadened. In order to gasify lignites in one of the projects, a transfer reactor was used. The specific cost of a CCGT with coal gasification rose in comparison with the period when such units started being designed, from 3000 up to 5500 dollars/kW.

Coal without carbon: an investment plan for federal action

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pettus, A.; Tatsutani, M.

2009-09-15

This study examines several technologies for CCS that are not currently receiving adequate development support but that could - in the right policy environment - provide the kind of significant cost reductions (and significant improvements in efficiency) that could greatly accelerate broad, economically attractive CCS deployment. Clean Air Task Force selected these technology areas (though not the technologies themselves) and solicited reports from experts in each field to explore how these technologies might fit into a broader CCS deployment strategy. Each expert was asked to develop a research, development, and demonstration (RD&D) 'road map' that could efficiently move each technologymore » from the laboratory into the commercial mainstream. Because the chapter authors are either technical experts or commercial players and are not, for the most part, energy policy experts, subsequent work will translate their RD&D recommendations into actionable policy proposals. The heart of this report consists of four chapters on advanced coal and CCS technologies: underground coal gasification (UCG), written by Julio Friedmann at Lawrence Livermore National Laboratory; Next generation coal gasification (surface-based gasification) led by Eric Redman at Summit Power Group; Advanced technologies for post-combustion capture (PCC) of CO{sub 2}, led by Howard Herzog at Massachusetts Institute of Technology; and RD&D to speed commercialization of geological CO{sub 2} sequestration (GCS), led by Julio Friedmann. 12 refs., 5 figs., 2 tabs.« less

Thermochemical conversion of waste tyres-a review.

PubMed

Labaki, Madona; Jeguirim, Mejdi

2017-04-01

A review of the energy recovery from waste tyres is presented and focuses on the three thermochemical processes used to valorise waste tyres: pyrolysis, gasification, and combustion/incineration. After recalling the chemical composition of tyres, the thermogravimetric behaviours of tyres or their components under different atmospheres are described. Different kinetic studies on the thermochemical processes are treated. Then, the three processes were investigated, with a particular attention given to the gasification, due to the information unavailability on this process. Pyrolysis is a thermochemical conversion to produce a hydrocarbon rich gas mixture, condensable liquids or tars, and a carbon-rich solid residue. Gasification is a form of pyrolysis, carried out at higher temperatures and under given atmosphere (air, steam, oxygen, carbon dioxide, etc.) in order to yield mainly low molecular weight gaseous products. Combustion is a process that needs a fuel and an oxidizer with an ignition system to produce heat and/or steam. The effects of various process parameters such as temperature, heating rate, residence time, catalyst addition, etc. on the energy efficiency and the products yields and characteristics are mainly reviewed. These thermochemical processes are considered to be the more attractive and practicable methods for recovering energy and material from waste tyres. For the future, they are the main promising issue to treat and valorise used tyres. However, efforts should be done in developing more efficient technical systems.

Energy implications of the thermal recovery of biodegradable municipal waste materials in the United Kingdom

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burnley, Stephen, E-mail: s.j.burnley@open.ac.uk; Phillips, Rhiannon, E-mail: rhiannon.jones@environment-agency.gov.uk; Coleman, Terry, E-mail: terry.coleman@erm.com

2011-09-15

Highlights: > Energy balances were calculated for the thermal treatment of biodegradable wastes. > For wood and RDF, combustion in dedicated facilities was the best option. > For paper, garden and food wastes and mixed waste incineration was the best option. > For low moisture paper, gasification provided the optimum solution. - Abstract: Waste management policies and legislation in many developed countries call for a reduction in the quantity of biodegradable waste landfilled. Anaerobic digestion, combustion and gasification are options for managing biodegradable waste while generating renewable energy. However, very little research has been carried to establish the overall energymore » balance of the collection, preparation and energy recovery processes for different types of wastes. Without this information, it is impossible to determine the optimum method for managing a particular waste to recover renewable energy. In this study, energy balances were carried out for the thermal processing of food waste, garden waste, wood, waste paper and the non-recyclable fraction of municipal waste. For all of these wastes, combustion in dedicated facilities or incineration with the municipal waste stream was the most energy-advantageous option. However, we identified a lack of reliable information on the energy consumed in collecting individual wastes and preparing the wastes for thermal processing. There was also little reliable information on the performance and efficiency of anaerobic digestion and gasification facilities for waste.« less

DOE Coal Gasification Multi-Test Facility: fossil fuel processing technical/professional services

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hefferan, J.K.; Lee, G.Y.; Boesch, L.P.

1979-07-13

A conceptual design, including process descriptions, heat and material balances, process flow diagrams, utility requirements, schedule, capital and operating cost estimate, and alternative design considerations, is presented for the DOE Coal Gasification Multi-Test Facility (GMTF). The GMTF, an engineering scale facility, is to provide a complete plant into which different types of gasifiers and conversion/synthesis equipment can be readily integrated for testing in an operational environment at relatively low cost. The design allows for operation of several gasifiers simultaneously at a total coal throughput of 2500 tons/day; individual gasifiers operate at up to 1200 tons/day and 600 psig using airmore » or oxygen. Ten different test gasifiers can be in place at the facility, but only three can be operated at one time. The GMTF can produce a spectrum of saleable products, including low Btu, synthesis and pipeline gases, hydrogen (for fuel cells or hydrogasification), methanol, gasoline, diesel and fuel oils, organic chemicals, and electrical power (potentially). In 1979 dollars, the base facility requires a $288 million capital investment for common-use units, $193 million for four gasification units and four synthesis units, and $305 million for six years of operation. Critical reviews of detailed vendor designs are appended for a methanol synthesis unit, three entrained flow gasifiers, a fluidized bed gasifier, and a hydrogasifier/slag-bath gasifier.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mann, M.K.

Technoeconomic analyses have been conducted on two processes to produce hydrogen from biomass: indirectly-heated gasification of biomass followed by steam reforming of the syngas, and biomass pyrolysis followed by steam reforming of the pyrolysis oil. The analysis of the gasification-based process was highly detailed, including a process flowsheet, material and energy balances calculated with a process simulation program, equipment cost estimation, and the determination of the necessary selling price of hydrogen. The pyrolysis-based process analysis was of a less detailed nature, as all necessary experimental data have not been obtained; this analysis is a follow-up to the preliminary economic analysismore » presented at the 1994 Hydrogen Program Review. A coproduct option in which pyrolysis oil is used to produce hydrogen and a commercial adhesive was also studied for economic viability. Based on feedstock availability estimates, three plant sizes were studied: 907 T/day, 272 T/day, and 27 T/day. The necessary selling price of hydrogen produced by steam reforming syngas from the Battelle Columbus Laboratories indirectly heated biomass gasifier falls within current market values for the large and medium size plants within a wide range of feedstock costs. Results show that the small scale plant does not produce hydrogen at economically competitive prices, indicating that if gasification is used as the upstream process to produce hydrogen, local refueling stations similar to current gasoline stations, would probably not be feasible.« less

Sliding-surface-liquefaction of sand-dry ice mixture and submarine landslides

NASA Astrophysics Data System (ADS)

Fukuoka, H.; Tsukui, A.

2010-12-01

In the historic records of off-shore mega-earthquakes along the subduction zone offshore Japan, there are a lot of witnesses about large-scale burning of flammable gas possibly ejected from sea floor. This gas was supposed to be the dissolved methane hydrates (MH), which have been found in the soundings of IODP and other oceanology projects. Since the vast distribution of the BSR in the continental margins, a lot of papers have been published which pointed out the possibilities of that gasification of those hydrates could have triggered gigantic submarine landslides. Global warming or large earthquake or magma intrusion may trigger extremely deep gigantic landslides in continental margins that which could cause catastrophic tsunami. However, recent triaxial compression tests on artificially prepared sand-MH-mixture samples revealed that the they have slightly higher strength than the ones of only sands and MH’s endothermal characteristics may resist against accelerating shear and large-displacement landslides as well. While, the stress-controlled undrained ring shear apparatuses have been developed by Sassa and Fukuoka at Disaster Prevention Research Institute, Kyoto University to reproduce subaerial landslides induced by earthquakes and rainfalls. Using the apparatuses, they found localized liquefaction phenomenon along the deep saturated potential sliding surface due to excess pore pressure generation during the grain crushing induced bulk volume change. This phenomenon was named as “sliding surface liquefaction.” Similar sudden large pore pressure generation was observed in pore pressure control test simulating rain-induced landslides. In this paper, authors examined the shear behavior of the dry sand-dry ice mixture under constant normal stress and shear speed control tests using the latest ring shear apparatus. Sample was mixture of silica sands and dry-ice pellets (frozen carbon-dioxide). Those mixtures are often used for studying the mechanism of the methane hydrates in laboratories because no explosion protection facility is required. In order to prevent rapid gasification, the specimen was prepared without water. Applied total normal stress was 200 kPa and initial normal stress was maintained at about 70 kPa by slightly opening the drainage valve to vent pressured CO2 gas. When the sample was sheared at 30 cm/s, the stress path reached failure line of friction angle of about 37 degrees immediately. However, excess pore air pressure increased soon after and the stress path moved to the origin along the failure line. This means rapid shearing generates frictional heat and it accelerates the gasification of dry ice quickly. On the other hand, crushing of pellets may contribute to increase the total surface area of dry ice and to acceleration of gasification, to some extent. Authors are conducting to examine the velocity weakening characteristics of the samples and upcoming results will give more detail of the mechanism. But this sliding-surface-liquefaction in the mixture supports the possibility of similar accelerating displacement in the sand-MH mixture or boundaries between MH and sand layer induced by certain strong ground motion under sea floor.

Experimental Studies of Coal and Biomass Fuel Synthesis and Flame Characterization for Aircraft Engines (Year Two)

DTIC Science & Technology

2011-03-31

2.1 Experimental Investigation of Coal and Biomass Gasification using In-situ Diagnostics ................ 31  2.2 References...need for fundamental scientific and synergistic research in catalytic biomass fast-hydropyrolysis, advanced coal gasification and liquid fuel...experimental findings will improve the scientific knowledge of catalytic biomass fast-hydropyrolysis, coal/ biomass gasification and liquid fuel combustion

Report of the DOD-DOE Workshop on Converting Waste to Energy Using Fuel Cells

DTIC Science & Technology

2011-10-01

for both at current costs, when federal and state incentives are available • The integration of stationary fuel cells with biomass gasification is a... gasification plant utilizing biomass feedstock. 25 FuelCell Energy Market Research, January 2011...cell WTE opportunities near U.S. Department of Energy (DOE)-supported coal gasification sites. • Identify biomass -rich DOD installations

Coal conversion processes and analysis methodologies for synthetic fuels production. [technology assessment and economic analysis of reactor design for coal gasification

NASA Technical Reports Server (NTRS)

1979-01-01

Information to identify viable coal gasification and utilization technologies is presented. Analysis capabilities required to support design and implementation of coal based synthetic fuels complexes are identified. The potential market in the Southeast United States for coal based synthetic fuels is investigated. A requirements analysis to identify the types of modeling and analysis capabilities required to conduct and monitor coal gasification project designs is discussed. Models and methodologies to satisfy these requirements are identified and evaluated, and recommendations are developed. Requirements for development of technology and data needed to improve gasification feasibility and economies are examined.

Gaseous fuels production from dried sewage sludge via air gasification.

PubMed

Werle, Sebastian; Dudziak, Mariusz

2014-07-01

Gasification is a perspective alternative method of dried sewage sludge thermal treatment. For the purpose of experimental investigations, a laboratory fixed-bed gasifier installation was designed and built. Two sewage sludge (SS) feedstocks, taken from two typical Polish wastewater treatment systems, were analysed: SS1, from a mechanical-biological wastewater treatment system with anaerobic stabilization (fermentation) and high temperature drying; and (SS2) from a mechanical-biological-chemical wastewater treatment system with fermentation and low temperature drying. The gasification results show that greater oxygen content in sewage sludge has a strong influence on the properties of the produced gas. Increasing the air flow caused a decrease in the heating value of the produced gas. Higher hydrogen content in the sewage sludge (from SS1) affected the produced gas composition, which was characterized by high concentrations of combustible components. In the case of the SS1 gasification, ash, charcoal, and tar were produced as byproducts. In the case of SS2 gasification, only ash and tar were produced. SS1 and solid byproducts from its gasification (ash and charcoal) were characterized by lower toxicity in comparison to SS2. However, in all analysed cases, tar samples were toxic. © The Author(s) 2014.

Experimental study of biomass gasification with oxygen-enriched air in fluidized bed gasifier.

PubMed

Liu, Lingqin; Huang, Yaji; Cao, Jianhua; Liu, Changqi; Dong, Lu; Xu, Ligang; Zha, Jianrui

2018-06-01

Considering the universality, renewability and cleanness of biomass, an experimental research is carried out using rice straw in a two-stage fluidized bed. The experimental analysis identified the relevant parameters in the operation of the two-stage fluidized bed to investigate the properties of biomass enriched air gasification. Results show that higher gasification temperature is conducive to enhance the gasification performance. An increasing ER is shown to go against adding gas heat value. When oxygen concentration increases from 21% to 45%, the gas heating value increases from 4.00MJ/kg to 5.24MJ/kg and the gasification efficiency increases from 29.60% to 33.59%, which shows higher oxygen concentration is conducive to higher quality gas and higher gasification efficiency. A secondary oxygen injection leads to reduction of tar concentration from 15.78g/Nm 3 to 10.24g/Nm 3 . The optimal secondary oxygen ratio is about 33.00%. When the secondary oxygen ratio increased to 46.86%, monocyclic aromatics reduced from 28.17% to 19.65% and PAHs increased from 34.97% to 44.05%, leading to the increase aromatization of tar. Copyright © 2018 Elsevier B.V. All rights reserved.

Coking and gasification process

DOEpatents

Billimoria, Rustom M.; Tao, Frank F.

1986-01-01

An improved coking process for normally solid carbonaceous materials wherein the yield of liquid product from the coker is increased by adding ammonia or an ammonia precursor to the coker. The invention is particularly useful in a process wherein coal liquefaction bottoms are coked to produce both a liquid and a gaseous product. Broadly, ammonia or an ammonia precursor is added to the coker ranging from about 1 to about 60 weight percent based on normally solid carbonaceous material and is preferably added in an amount from about 2 to about 15 weight percent.

Thermal Cracking of Tars in a Continuously Fed Reactor with Steam

DTIC Science & Technology

2011-05-01

Fluidized Bed using biomass 8 Tars  Mixture of organic components present in gasification product gas with high molecular weight hydrocarbons [MW...Disable sulfur removal systems FoulingPlugging [Ref. 3: Biomass Gasification – Tar and Particles in Product Gases Sampling and Analysis”, European...P., and Nussbaumer T., “Gas Cleaning Requirements for Internal Combustion Engine Applications of Fixed Bed Biomass Gasification ”, Biomass and

Proceedings of the 1st Army Installation Waste to Energy Workshop

DTIC Science & Technology

2008-08-01

Center 2902 Newmark Dr. Champaign, IL 61824 René S. Parker Select Engineering Services (SES) 1544 Woodland Park Ave. Suite 310 Layton , UT 84041...gasification technologies at different scales (Source: Larson, Eric D., “Small-Scale Gasification-Based Biomass Power Generation,” January 1998...Engineering Research Laboratory. Larson, Eric D. 1998. Small-scale gasification-based biomass power generation. Prepared for the Biomass Workshop

Biomass waste gasification - can be the two stage process suitable for tar reduction and power generation?

PubMed

Sulc, Jindřich; Stojdl, Jiří; Richter, Miroslav; Popelka, Jan; Svoboda, Karel; Smetana, Jiří; Vacek, Jiří; Skoblja, Siarhei; Buryan, Petr

2012-04-01

A pilot scale gasification unit with novel co-current, updraft arrangement in the first stage and counter-current downdraft in the second stage was developed and exploited for studying effects of two stage gasification in comparison with one stage gasification of biomass (wood pellets) on fuel gas composition and attainable gas purity. Significant producer gas parameters (gas composition, heating value, content of tar compounds, content of inorganic gas impurities) were compared for the two stage and the one stage method of the gasification arrangement with only the upward moving bed (co-current updraft). The main novel features of the gasifier conception include grate-less reactor, upward moving bed of biomass particles (e.g. pellets) by means of a screw elevator with changeable rotational speed and gradual expanding diameter of the cylindrical reactor in the part above the upper end of the screw. The gasifier concept and arrangement are considered convenient for thermal power range 100-350 kW(th). The second stage of the gasifier served mainly for tar compounds destruction/reforming by increased temperature (around 950°C) and for gasification reaction of the fuel gas with char. The second stage used additional combustion of the fuel gas by preheated secondary air for attaining higher temperature and faster gasification of the remaining char from the first stage. The measurements of gas composition and tar compound contents confirmed superiority of the two stage gasification system, drastic decrease of aromatic compounds with two and higher number of benzene rings by 1-2 orders. On the other hand the two stage gasification (with overall ER=0.71) led to substantial reduction of gas heating value (LHV=3.15 MJ/Nm(3)), elevation of gas volume and increase of nitrogen content in fuel gas. The increased temperature (>950°C) at the entrance to the char bed caused also substantial decrease of ammonia content in fuel gas. The char with higher content of ash leaving the second stage presented only few mass% of the inlet biomass stream. Copyright © 2011 Elsevier Ltd. All rights reserved.

Health risk assessment as an approach to manage an old landfill and to propose integrated solid waste treatment: A case study in Italy.

PubMed

Paladino, O; Massabò, M

2017-10-01

The aim of the present paper is to show how an approach based on human health risk analysis can be used as a decisional tool for the evaluation of impacts on population and for deciding between different waste treatment processes. The situation in which the increasing production of solid wastes cannot be confined in the old existing Municipal Solid Waste landfill (settled in Genoa, Liguria Region, Italy) is used as a case study. Risk assessment for human health due to air, surface water, groundwater and soil contamination is performed in different scenarios for the old landfill and compared with alternative Waste-to-Energy management solutions that consider thermal treatment by gasification of the total waste or gasification of the dry fraction coupled with anaerobic digestion of the wet fraction, plus biogas combustion with or without sludge and bottom ash/slag disposal in the old landfill. Hazard Index (HI) and Cancer Risk (CR) in case of operating landfill and under the suspected situation of failure of the sealing system, were respectively 1.15 and 1.1∗10 -7 . Unacceptable HI were found due to groundwater contamination, while HI due to river pollution was slightly under the threshold. Vegetables ingestion was the most important pathway and ammonia the most responsible of toxic adverse effects. Fish ingestion and dermal contact with contaminated water were found to be the most important exposure pathways for carcinogenic risk, due mainly to BTEX. HI and CR in the supposed scenario of total waste gasification were respectively 9.4∗10 -1 and 1.1∗10 -5 while they were respectively 3.2∗10 -1 and 6∗10 -6 in case of gasification of the dry fraction. CR in both scenarios was over the threshold mainly due to dioxins, where milk and meat ingestion were found to be the highest risk pathways. Inhalation resulted as the highest not-carcinogenic risk exposure pathway, mainly due to NOx. Decision making was made by weighing up the different scenarios, and results suggested to definitively close the landfill and to eliminate gasification of the total waste as a possible waste treatment process. Copyright © 2017 Elsevier Ltd. All rights reserved.

Application and Discussion of Dual Fluidized Bed Reactor in Biomass Energy Utilization

NASA Astrophysics Data System (ADS)

Guan, Haibin; Fan, Xiaoxu; Zhao, Baofeng; Yang, Liguo; Sun, Rongfeng

2018-01-01

As an important clean and renewable energy, biomass has a broad market prospect. The dual fluidized bed is widely used in biomass gasification technology, and has become an important way of biomass high-value utilization. This paper describes the basic principle of dual fluidized bed gasification, from the gas composition, tar content and thermal efficiency of the system point of view, analyzes and summarizes several typical dual fluidized bed biomass gasification technologies, points out the existence of gas mixing, the external heat source, catalyst development problems on gas. Finally, it is clear that the gasification of biomass in dual fluidized bed is of great industrial application and development prospect.

Gasification of Wood and Non-wood Waste of Timber Production as Perspectives for Development of Bioenergy

NASA Astrophysics Data System (ADS)

Kislukhina, Irina A.; Rybakova, Olga G.

2018-03-01

The article deals with biomass gasification technology using the gasification plant running on wood chips and pellets, produced from essential oils waste (waste of coniferous boughs). During the study, the authors solved the process task of improving the quality of the product gas derived from non-wood waste of timber production (coniferous boughs) due to the extraction of essential oils and the subsequent thermal processing of spent coniferous boughs at a temperature of 250-300°C degrees without oxygen immediately before pelleting. The paper provides the improved biomass gasification process scheme including the grinding of coniferous boughs, essential oil distillation and thermal treatment of coniferous boughs waste and pelletizing.

Gaseous fuel production from nonrecyclable paper wastes by using supported metal catalysts in high-temperature liquid water.

PubMed

Yamaguchi, Aritomo; Hiyoshi, Norihito; Sato, Osamu; Bando, Kyoko K; Shirai, Masayuki

2010-06-21

Paper wastes are used for the production of gaseous fuels over supported metal catalysts. The gasification of the nonrecyclable paper wastes, such as shredded documents and paper sludge, is carried out in high-temperature liquid water. The order of the catalytic activity for the gasification is found to be ruthenium>rhodium>platinum>palladium. A charcoal-supported ruthenium catalyst (Ru/C) is the most effective for the gasification of paper and cellulose. Paper wastes are gasified to a limited degree (32.6 carbon %) for 30 min in water at 523 K to produce methane and carbon dioxide, with a small amount of hydrogen. At 573 K, more complete gasification with almost 100 carbon % is achieved within 10 min in water. At 523 K, the gas yield of paper gasification over Ru/C is higher than that of cellulose powder. The gas yields are increased by ball-milling treatment of the recycled paper and cellulose powder. Printed paper wastes are also gasified at 523 K in water.

Co-gasification of pine and oak biochar with sub-bituminous coal in carbon dioxide.

PubMed

Beagle, E; Wang, Y; Bell, D; Belmont, E

2018-03-01

Pine and oak biochars derived as byproducts of demonstration-scale pyrolysis, and blends of these two feedstocks with Powder River Basin coal, were gasified in a carbon dioxide environment using a modified drop tube reactor (MDTR) and a thermogravimetric analyzer (TGA). The impact of gasification temperature on conversion kinetics was evaluated from the temporal evolution of major product gases in the MDTR as measured using a mass spectrometer. Random pore modeling was conducted to simulate gasification in the MDTR with favorable results. The MDTR and TGA were used to conduct gasification for assessment of non-linear additive effects in the blends. Additive analysis of the blends showed deviation from the experimental blend results, indicating inhibiting effects of co-gasifying the biochar and coal. Inhibitory effects are more significant for oak than pine and more pronounced in the TGA at lower gasification temperatures. Results are discussed in the context of feedstock and reactor type. Copyright © 2017 Elsevier Ltd. All rights reserved.

Behaviors of Char Gasification Based on Two-stage Gasifier of Biomass

NASA Astrophysics Data System (ADS)

Taniguchi, Miki; Sasauchi, Kenichi; Ahn, Chulju; Ito, Yusuke; Hayashi, Toshiaki; Akamatsu, Fumiteru

In order to develop a small-scale gasifier in which biomass can be converted to energy with high efficiency, we planed a gasification process that consists of two parts: pyrolysis part (rotary kiln) and gasification part (downdraft gasifier). We performed fundamental experiments on gasification part and discussed the apropriate conditions such as air supply location, air ratio, air temperature and hearth load. The following results was found: 1) the air supply into the char bed is more effective than that into the gas phase, 2) we can have the maximum cold gas efficiency of 80% on the following conditions: air supply location: char layer, air temperature: 20°C, air ratio: 0.2. 3) As air temperature is higher, the cold gas efficiency is larger. As for the hearth load, the cold gas efficiency becomes higher and reaches the constant level. It is expected from the results that high temperature in the char layer is effective on the char gasification.

Characterization of Scots pine stump-root biomass as feed-stock for gasification.

PubMed

Eriksson, Daniel; Weiland, Fredrik; Hedman, Henry; Stenberg, Martin; Öhrman, Olov; Lestander, Torbjörn A; Bergsten, Urban; Öhman, Marcus

2012-01-01

The main objective was to explore the potential for gasifying Scots pine stump-root biomass (SRB). Washed thin roots, coarse roots, stump heartwood and stump sapwood were characterized (solid wood, milling and powder characteristics) before and during industrial processing. Non-slagging gasification of the SRB fuels and a reference stem wood was successful, and the gasification parameters (synthesis gas and bottom ash characteristics) were similar. However, the heartwood fuel had high levels of extractives (≈19%) compared to the other fuels (2-8%) and thereby ≈16% higher energy contents but caused disturbances during milling, storage, feeding and gasification. SRB fuels could be sorted automatically according to their extractives and moisture contents using near-infrared spectroscopy, and their amounts and quality in forests can be predicted using routinely collected stand data, biomass functions and drill core analyses. Thus, SRB gasification has great potential and the proposed characterizations exploit it. Copyright © 2011 Elsevier Ltd. All rights reserved.

Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO 2 Capture

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kathe, Mandar; Xu, Dikai; Hsieh, Tien-Lin

2014-12-31

This document is the final report for the project titled “Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO 2 Capture” under award number FE0012136 for the performance period 10/01/2013 to 12/31/2014.This project investigates the novel Ohio State chemical looping gasification technology for high efficiency, cost efficiency coal gasification for IGCC and methanol production application. The project developed an optimized oxygen carrier composition, demonstrated the feasibility of the concept and completed cold-flow model studies. WorleyParsons completed a techno-economic analysis which showed that for a coal only feed with carbon capture, the OSU CLG technology reduced the methanol requiredmore » selling price by 21%, lowered the capital costs by 28%, increased coal consumption efficiency by 14%. Further, using the Ohio State Chemical Looping Gasification technology resulted in a methanol required selling price which was lower than the reference non-capture case.« less

Physicochemical evolution during rice straw and coal co-pyrolysis and its effect on co-gasification reactivity.

PubMed

Wei, Juntao; Gong, Yan; Guo, Qinghua; Ding, Lu; Wang, Fuchen; Yu, Guangsuo

2017-03-01

Physicochemical evolution (i.e. pore structure variation, carbon structure change and active AAEM transformation) during rice straw (RS) and Shenfu bituminous coal (SF) co-pyrolysis was quantitatively determined in this work. Moreover, the corresponding char gasification was conducted using a thermogravimetric analyzer (TGA) and relative reactivity was proposed to quantify the co-pyrolysis impact on co-gasification reactivity. The results showed that the development of pore structure in co-pyrolyzed chars was first inhibited and then enhanced with the decrease of SF proportion. The promotion effect of co-pyrolysis on order degree of co-pyrolyzed chars gradually weakened with increasing RS proportion. Co-pyrolysis mainly enhanced active K transformation in co-pyrolyzed chars and the promotion effect was alleviated with increasing RS proportion. The inhibition effect of co-pyrolysis on co-gasification reactivity weakened with increasing RS proportion and gasification temperature, which was mainly attributed to the combination of carbon structure evolution and active AAEM transformation in co-pyrolysis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hydrogen production from algal biomass via steam gasification.

PubMed

Duman, Gozde; Uddin, Md Azhar; Yanik, Jale

2014-08-01

Algal biomasses were tested as feedstock for steam gasification in a dual-bed microreactor in a two-stage process. Gasification experiments were carried out in absence and presence of catalyst. The catalysts used were 10% Fe₂O₃-90% CeO₂ and red mud (activated and natural forms). Effects of catalysts on tar formation and gasification efficiencies were comparatively investigated. It was observed that the characteristic of algae gasification was dependent on its components and the catalysts used. The main role of the catalyst was reforming of the tar derived from algae pyrolysis, besides enhancing water gas shift reaction. The tar reduction levels were in the range of 80-100% for seaweeds and of 53-70% for microalgae. Fe₂O₃-CeO₂ was found to be the most effective catalyst. The maximum hydrogen yields obtained were 1036 cc/g algae for Fucus serratus, 937 cc/g algae for Laminaria digitata and 413 cc/g algae for Nannochloropsis oculata. Copyright © 2014 Elsevier Ltd. All rights reserved.

Steam gasification of acid-hydrolysis biomass CAHR for clean syngas production.

PubMed

Chen, Guanyi; Yao, Jingang; Yang, Huijun; Yan, Beibei; Chen, Hong

2015-03-01

Main characteristics of gaseous product from steam gasification of acid-hydrolysis biomass CAHR have been investigated experimentally. The comparison in terms of evolution of syngas flow rate, syngas quality and apparent thermal efficiency was made between steam gasification and pyrolysis in the lab-scale apparatus. The aim of this study was to determine the effects of temperature and steam to CAHR ratio on gas quality, syngas yield and energy conversion. The results showed that syngas and energy yield were better with gasification compared to pyrolysis under identical thermal conditions. Both high gasification temperature and introduction of proper steam led to higher gas quality, higher syngas yield and higher energy conversion efficiency. However, excessive steam reduced hydrogen yield and energy conversion efficiency. The optimal value of S/B was found to be 3.3. The maximum value of energy ratio was 0.855 at 800°C with the optimal S/B value. Copyright © 2014 Elsevier Ltd. All rights reserved.

Green Power Initiative

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butler, Patrick Barry

2013-01-28

National energy policy supports the gathering of more detailed and authoritative data on the introduction of renewable bio-based fuels into new and existing district energy systems via the application of biomass gasification. The University of Iowa developed a biomass-fueled, university-scale steam generation system based on biomass gasification technologies. The system serves as a state-of-the-art research and educational facility in the emerging application of gasification in steam generation. The facility, which includes a smaller down-draft gasifier and a larger multi-stage biomass boiler, was designed to operate primarily on wood-based fuels, but has provisions for testing other biomass fuel sources produced withinmore » a 100-mile radius, providing enough flexibility to meet the fluctuating local supply of biomass from industry and Midwest agriculture. The equipment was installed in an existing, staffed facility. The down-draft gasifier unit is operated by College of Engineering staff and students, under the direct technical supervision of qualified Utilities plant staff. The Green Power Initiative also includes a substantial, innovative educational component. In addition to an onsite, graduate-level research program in biomass fuels, the investigators have integrated undergraduate and graduate level teaching – through classroom studies and experiential learning – and applied research into a biomass-based, university-scale, functioning power plant. University of Iowa is unique in that it currently has multiple renewable energy technologies deployed, including significant biomass combustion (oat hulls) at its Main Power Plant and a new reciprocating engine based renewable district energy system. This project complements and supports the national energy policy and State of Iowa initiatives in ethanol and biodiesel. Byproducts of ethanol and biodiesel processes (distiller grains) as well as industry residues (oat hulls, wood chips, construction and demolition waste), farm related material (seed corn and soybean seed), and poplar trees for cleaning up ground water are logical feed stocks for gasification.« less

Sustainable Land Use for Bioenergy in the 21st Century

DTIC Science & Technology

2011-06-01

as pyrolysis and gasification are also applicable to burn biomass and produce electricity.61–63 Biomass can be used directly in existing co- fired...engineering specifications that may ultimately lead to high process efficiency. COMPARISON OF BIOMASS THERMAL CONVERSION PROCESSES Gasification ...thermal gasification of biomass and its application to electricity and fuel production. Biomass and Bioenergy 2008;32(7):573–581. 62. Caputo AC

Impact of feedstock properties and operating conditions on sewage sludge gasification in a fixed bed gasifier.

PubMed

Werle, Sebastian

2014-10-01

This work presents results of experimental studies on the gasification process of granulated sewage sludge in a laboratory fixed bed gasifier. Nowadays, there is a large and pressing need for the development of thermal methods for sewage sludge disposal. Gasification is an example of thermal method that has several advantages over the traditional combustion. Gasification leads to a combustible gas, which can be used for the generation of useful forms of final energy. It can also be used in processes, such as the drying of sewage sludge directly in waste treatment plant. In the present work, the operating parameters were varied over a wide range. Parameters, such as air ratio λ = 0.12 to 0.27 and the temperature of air preheating t = 50 °C to 250 °C, were found to influence temperature distribution and syngas properties. The results indicate that the syngas heating value decreases with rising air ratio for all analysed cases: i.e. for both cold and preheated air. The increase in the concentration of the main combustible components was accompanied by a decrease in the concentration of carbon dioxide. Preheating of the gasification agent supports the endothermic gasification and increases hydrogen and carbon monoxide production. © The Author(s) 2014.

Numerical simulation of waste tyres gasification.

PubMed

Janajreh, Isam; Raza, Syed Shabbar

2015-05-01

Gasification is a thermochemical pathway used to convert carbonaceous feedstock into syngas (CO and H2) in a deprived oxygen environment. The process can accommodate conventional feedstock such as coal, discarded waste including plastics, rubber, and mixed waste owing to the high reactor temperature (1000 °C-1600 °C). Pyrolysis is another conversion pathway, yet it is more selective to the feedstock owing to the low process temperature (350 °C-550 °C). Discarded tyres can be subjected to pyrolysis, however, the yield involves the formation of intermediate radicals additional to unconverted char. Gasification, however, owing to the higher temperature and shorter residence time, is more opted to follow quasi-equilibrium and being predictive. In this work, tyre crumbs are subjected to two levels of gasification modelling, i.e. equilibrium zero dimension and reactive multi-dimensional flow. The objective is to investigate the effect of the amount of oxidising agent on the conversion of tyre granules and syngas composition in a small 20 kW cylindrical gasifier. Initially the chemical compositions of several tyre samples are measured following the ASTM procedures for proximate and ultimate analysis as well as the heating value. The measured data are used to carry out equilibrium-based and reactive flow gasification. The result shows that both models are reasonably predictive averaging 50% gasification efficiency, the devolatilisation is less sensitive than the char conversion to the equivalence ratio as devolatilisation is always complete. In view of the high attained efficiency, it is suggested that the investigated tyre gasification system is economically viable. © The Author(s) 2015.

Model-based estimation of adiabatic flame temperature during coal gasification

NASA Astrophysics Data System (ADS)

Sarigul, Ihsan Mert

Coal gasification temperature distribution in the gasifier is one of the important issues. High temperature may increase the risk of corrosion of the gasifier wall or it may cause an increase in the amount of volatile compounds. At the same time, gasification temperature is a dominant factor for high conversion of products and completing the reactions during coal gasification in a short time. In the light of this information it can be said that temperature is one of key parameters of coal gasification to enhance the production of high heating value syngas and maximize refractory longevity. This study aims to predict the adiabatic flame temperatures of Australian bituminous coal and Indonesian roto coal in an entrained flow gasifier using different operating conditions with the ChemCAD simulation and design program. To achieve these objectives, two types of gasification parameters were carried out using simulation of a vertical entrained flow reactor: oxygen-to-coal feed ratio by kg/kg and pressure and steam-to-coal feed ratio by kg/kg and pressure. In the first part of study the adiabatic flame temperatures, coal gasification products and other coal characteristics of two types of coals were determined using ChemCAD software. During all simulations, coal feed rate, coal particle size, initial temperature of coal, water and oxygen were kept constant. The relationships between flame temperature, coal gasification products and operating parameters were fundamentally investigated. The second part of this study addresses the modeling of the flame temperature relation to methane production and other input parameters used previous chapter. The scope of this work was to establish a reasonable model in order to estimate flame temperature without any theoretical calculation. Finally, sensitivity analysis was performed after getting some basic correlations between temperature and input variables. According to the results, oxygen-to-coal feed ratio has the most influential effect on adiabatic flame temperature.

Gasification of empty fruit bunch with carbon dioxide in an entrained flow gasifier for syngas production

NASA Astrophysics Data System (ADS)

Rahmat, N. F. H.; Rasid, R. A.

2017-06-01

The main objectives of this work are to study the gasification of EFB in an atmospheric entrained flow gasifier, using carbon dioxide (CO2) as its gasifying agent and to determine the optimum gasification operating conditions, which includes temperature and the oxidant to fuel (OTF) ratio. These were evaluated in terms of important gasification parameters such as the concentration of hydrogen (H2) and carbon monoxide (CO) produced the syngas ratio H2/CO and carbon conversion. The gasification reactions take place in the presence of CO2 at very high reaction rate because of the high operating temperature (700°C - 900°C). The use of CO2 as the oxidant for gasification process can improve the composition of syngas produced as in the Boudouard reaction. Rise of reaction temperature which is 900°C will increase the concentration of both H2 & CO by up to 81 and 30 respectively, though their production were decreased after the OTF ratio of 0.6 for temperature 700°C & 800°C and OTF ratio 0.8 for temperature 750°C. The operating temperature must be higher than 850°C to ensure the Boudouard reaction become the more prominent reaction for the biomass gasification. The syngas ratio obtained was in the range of ≈ 0.6 - 2.4 which is sufficient for liquid fuel synthesis. For the carbon conversion, the highest fuel conversion recorded at temperature 850°C for all OTF ratios. As the OTF ratio increases, it was found that there was an increase in the formation of CO and H2. This suggests that to achieve higher carbon conversion, high operating temperature and OTF ratio are preferable. This study provides information on the optimum operating conditions for the gasification of biomass, especially the EFB, hence may upsurge the utilization of biomass waste as an energy source.

Techno-economic analysis of biofuel production considering logistic configurations.

PubMed

Li, Qi; Hu, Guiping

2016-04-01

In the study, a techno-economic analysis method considering logistic configurations is proposed. The economic feasibility of a low temperature biomass gasification pathway and an integrated pathway with fast pyrolysis and bio-oil gasification are evaluated and compared with the proposed method in Iowa. The results show that both pathways are profitable, biomass gasification pathway could achieve an Internal Rate of Return (IRR) of 10.00% by building a single biorefinery and integrated bio-oil gasification pathway could achieve an IRR of 3.32% by applying decentralized supply chain structure. A Monte-Carlo simulation considering interactions among parameters is also proposed and conducted, which indicates that both pathways are at high risk currently. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gasification of agricultural residues in a demonstrative plant: corn cobs.

PubMed

Biagini, Enrico; Barontini, Federica; Tognotti, Leonardo

2014-12-01

Biomass gasification couples the high power efficiency with the possibility of valuably using the byproducts heat and biochar. The use of agricultural wastes instead of woody feedstock extends the seasonal availability of biomasses. The downdraft type is the most used reactor but has narrow ranges of feedstock specifications (above all on moisture and particle size distribution), so tests on a demonstrative scale are conducted to prove the versatility of the gasifier. Measurements on pressure drops, syngas flow rate and composition are studied to assess the feasibility of such operations with corn cobs. Material and energy balances, and performance indexes are compared for the four tests carried out under different biomass loads (66-85 kg/h). A good operability of the plant and interesting results are obtained (gas specific production of 2 m3/kg, gas heating value 5.6-5.8 MJ/m3, cold gas efficiency in the range 66-68%, potential net power efficiency 21.1-21.6%). Copyright © 2014 Elsevier Ltd. All rights reserved.

Air gasification of rice husk in bubbling fluidized bed reactor with bed heating by conventional charcoal.

PubMed

Makwana, J P; Joshi, Asim Kumar; Athawale, Gaurav; Singh, Dharminder; Mohanty, Pravakar

2015-02-01

An experimental study of air gasification of rice husk was conducted in a bench-scale fluidized bed gasifier (FBG) having 210 mm diameter and 1600 mm height. Heating of sand bed material was performed using conventional charcoal fuel. Different operating conditions like bed temperature, feeding rate and equivalence ratio (ER) varied in the range of 750-850 °C, 25-31.3 kg/h, and 0.3-0.38, respectively. Flow rate of air was kept constant (37 m(3)/h) during FBG experiments. The carbon conversion efficiencies (CCE), cold gas efficiency, and thermal efficiency were evaluated, where maximum CCE was found as 91%. By increasing ER, the carbon conversion efficiency was decreased. Drastic reduction in electric consumption for initial heating of gasifier bed with charcoal compared to ceramic heater was ∼45%. Hence rice husk is found as a potential candidate to use directly (without any processing) in FBG as an alternative renewable energy source from agricultural field. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chemical activation of gasification carbon residue for phosphate removal

NASA Astrophysics Data System (ADS)

Kilpimaa, Sari; Runtti, Hanna; Lassi, Ulla; Kuokkanen, Toivo

2012-05-01

Recycling of waste materials provides an economical and environmentally significant method to reduce the amount of waste. Bioash formed in the gasification process possesses a notable amount of unburned carbon and therefore it can be called a carbon residue. After chemical activation carbon residue could be use to replace activated carbon for example in wastewater purification processes. The effect of chemical activation process variables such as chemical agents and contact time in the chemical activation process were investigated. This study also explored the effectiveness of the chemically activated carbon residue for the removal of phosphate from an aqueous solution. The experimental adsorption study was performed in a batch reactor and the influence of adsorption time, initial phosphate concentration and pH was studied. Due to the carbon residue's low cost and high adsorption capacity, this type of waste has the potential to be utilised for the cost-effective removal of phosphate from wastewaters. Potential adsorbents could be prepared from these carbonaceous by-products and used as an adsorbent for phosphate removal.

Evaluation of gasification and novel thermal processes for the treatment of municipal solid waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Niessen, W.R.; Marks, C.H.; Sommerlad, R.E.

1996-08-01

This report identifies seven developers whose gasification technologies can be used to treat the organic constituents of municipal solid waste: Energy Products of Idaho; TPS Termiska Processor AB; Proler International Corporation; Thermoselect Inc.; Battelle; Pedco Incorporated; and ThermoChem, Incorporated. Their processes recover heat directly, produce a fuel product, or produce a feedstock for chemical processes. The technologies are on the brink of commercial availability. This report evaluates, for each technology, several kinds of issues. Technical considerations were material balance, energy balance, plant thermal efficiency, and effect of feedstock contaminants. Environmental considerations were the regulatory context, and such things as composition,more » mass rate, and treatability of pollutants. Business issues were related to likelihood of commercialization. Finally, cost and economic issues such as capital and operating costs, and the refuse-derived fuel preparation and energy c onversion costs, were considered. The final section of the report reviews and summarizes the information gathered during the study.« less

Material and energy recovery from Automotive Shredded Residues (ASR) via sequential gasification and combustion.

PubMed

Viganò, F; Consonni, S; Grosso, M; Rigamonti, L

2010-01-01

Shredding is the common end-of-life treatment in Europe for dismantled car wrecks. It produces the so-called Automotive Shredded Residue (ASR), usually disposed of in landfill. This paper summarizes the outcome of a study carried out by Politecnico di Milano and LEAP with the support of Actelios SpA on the prospects of a technology based on sequential gasification and combustion of this specific waste stream. Its application to the treatment of ASR allows the recovery of large fractions of metals as non-oxidized, easily marketable secondary raw materials, the vitrification of most of the ash content and the production of power via a steam cycle. Results show that despite the unfavourable characteristics of ASR, the proposed technology can reach appealing energy performances. Three of four environmental impact indicators and the cumulative energy demand index are favourable, the main positive contributes being electricity production and metal recovery (mainly aluminium and copper). The only unfavourable indicator is the global warming index because, since most of the carbon in ASR comes from fossil sources, the carbon dioxide emissions at the stack of the thermal treatment plant are mainly non-renewable and, at the same time, the avoided biogas production from the alternative disposal route of landfilling is minor.

Thermal valorization of post-consumer film waste in a bubbling bed gasifier

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martínez-Lera, S., E-mail: susanamartinezlera@gmail.com; Torrico, J.; Pallarés, J.

2013-07-15

Highlights: • Film waste from packaging is a common waste, a fraction of which is not recyclable. • Gasification can make use of the high energy value of the non-recyclable fraction. • This waste and two reference polymers were gasified in a bubbling bed reactor. • This experimental research proves technical feasibility of the process. • It also analyzes impact of composition and ER on the performance of the plant. - Abstract: The use of plastic bags and film packaging is very frequent in manifold sectors and film waste is usually present in different sources of municipal and industrial wastes.more » A significant part of it is not suitable for mechanical recycling but could be safely transformed into a valuable gas by means of thermal valorization. In this research, the gasification of film wastes has been experimentally investigated through experiments in a fluidized bed reactor of two reference polymers, polyethylene and polypropylene, and actual post-consumer film waste. After a complete experimental characterization of the three materials, several gasification experiments have been performed to analyze the influence of the fuel and of equivalence ratio on gas production and composition, on tar generation and on efficiency. The experiments prove that film waste and analogue polymer derived wastes can be successfully gasified in a fluidized bed reactor, yielding a gas with a higher heating value in a range from 3.6 to 5.6 MJ/m{sup 3} and cold gas efficiencies up to 60%.« less

Characterization of cellulosic wastes and gasification products from chicken farms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joseph, Paul, E-mail: p.joseph@ulster.ac.uk; Tretsiakova-McNally, Svetlana; McKenna, Siobhan

Highlights: Black-Right-Pointing-Pointer The gas chromatography indicated the variable quality of the producer gas. Black-Right-Pointing-Pointer The char had appreciable NPK values, and can be used as a fertiliser. Black-Right-Pointing-Pointer The bio-oil produced was of poor quality, having high moisture content and low pH. Black-Right-Pointing-Pointer Mass and energy balances showed inadequate level energy recovery from the process. Black-Right-Pointing-Pointer Future work includes changing the operating parameters of the gasification unit. - Abstract: The current article focuses on gasification as a primary disposal solution for cellulosic wastes derived from chicken farms, and the possibility to recover energy from this process. Wood shavings and chickenmore » litter were characterized with a view to establishing their thermal parameters, compositional natures and calorific values. The main products obtained from the gasification of chicken litter, namely, producer gas, bio-oil and char, were also analysed in order to establish their potential as energy sources. The experimental protocol included bomb calorimetry, pyrolysis combustion flow calorimetry (PCFC), thermo-gravimetric analyses (TGA), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, elemental analyses, X-ray diffraction (XRD), mineral content analyses and gas chromatography. The mass and energy balances of the gasification unit were also estimated. The results obtained confirmed that gasification is a viable method of chicken litter disposal. In addition to this, it is also possible to recover some energy from the process. However, energy content in the gas-phase was relatively low. This might be due to the low energy efficiency (19.6%) of the gasification unit, which could be improved by changing the operation parameters.« less

Power Sources Focus Group - Evaluation of Plasma Gasification for Waste-to-Energy Conversion

DTIC Science & Technology

2012-09-21

including paper , wood, plastic, food and agricultural waste. The system uses a shredder, dryer , and pelletizing preprocessor to fuel an in-house...limited information available, this paper does not attempt to determine the best way to use plasma in a gasifier. Instead, this paper makes general...Gasification Plasma gasification for the purposes of this paper includes any WTE system using plasma as part of the generation of syngas and/or cleanup

Updraft Fixed Bed Gasification Aspen Plus Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

2007-09-27

The updraft fixed bed gasification model provides predictive modeling capabilities for updraft fixed bed gasifiers, when devolatilization data is available. The fixed bed model is constructed using Aspen Plus, process modeling software, coupled with a FORTRAN user kinetic subroutine. Current updraft gasification models created in Aspen Plus have limited predictive capabilities and must be "tuned" to reflect a generalized gas composition as specified in literature or by the gasifier manufacturer. This limits the applicability of the process model.

System and process for upgrading hydrocarbons

DOEpatents

Bingham, Dennis N.; Klingler, Kerry M.; Smith, Joseph D.; Turner, Terry D.; Wilding, Bruce M.

2015-08-25

In one embodiment, a system for upgrading a hydrocarbon material may include a black wax upgrade subsystem and a molten salt gasification (MSG) subsystem. The black wax upgrade subsystem and the MSG subsystem may be located within a common pressure boundary, such as within a pressure vessel. Gaseous materials produced by the MSG subsystem may be used in the process carried out within the black wax upgrade subsystem. For example, hydrogen may pass through a gaseous transfer interface to interact with black wax feed material to hydrogenate such material during a cracking process. In one embodiment, the gaseous transfer interface may include one or more openings in a tube or conduit which is carrying the black wax material. A pressure differential may control the flow of hydrogen within the tube or conduit. Related methods are also disclosed.

Hydrogen recovery from the thermal plasma gasification of solid waste.

PubMed

Byun, Youngchul; Cho, Moohyun; Chung, Jae Woo; Namkung, Won; Lee, Hyeon Don; Jang, Sung Duk; Kim, Young-Suk; Lee, Jin-Ho; Lee, Carg-Ro; Hwang, Soon-Mo

2011-06-15

Thermal plasma gasification has been demonstrated as one of the most effective and environmentally friendly methods for solid waste treatment and energy utilization in many of studies. Therefore, the thermal plasma process of solid waste gasification (paper mill waste, 1.2 ton/day) was applied for the recovery of high purity H(2) (>99.99%). Gases emitted from a gasification furnace equipped with a nontransferred thermal plasma torch were purified using a bag-filter and wet scrubber. Thereafter, the gases, which contained syngas (CO+H(2)), were introduced into a H(2) recovery system, consisting largely of a water gas shift (WGS) unit for the conversion of CO to H(2) and a pressure swing adsorption (PSA) unit for the separation and purification of H(2). It was successfully demonstrated that the thermal plasma process of solid waste gasification, combined with the WGS and PSA, produced high purity H(2) (20 N m(3)/h (400 H(2)-Nm(3)/PMW-ton), up to 99.99%) using a plasma torch with 1.6 MWh/PMW-ton of electricity. The results presented here suggest that the thermal plasma process of solid waste gasification for the production of high purity H(2) may provide a new approach as a future energy infrastructure based on H(2). Copyright © 2011 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, B.E.; Ahner, P.F.; Singelton, A.H.

In situ gasification of steeply dipping coal beds (UCG-SDB) has significant advantages over the more conventional horizontal UCG. In fact, the UCG-SDB process appears to be both technically and operationally competitive with surface gasifiers. The results of the Rawlins UCG-SDB field test program suggest that the process can compete with more conventional sources of synthesis gas on an economic basis. The SDB process mechanism has several advantages over the horizontal process and performs in a fashion similar to surface packedbed reactors. The oxygen requirements for the process are quite low and the degree of process control observed at Rawlins ismore » very attractive.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, B.E.; Ahner, P.F.

In-situ gasification of steeply dipping coal beds (UCG-SDB) has significant advantages over the more conventional horizontal UCG. In fact, the UCG-SDB process appears to be both technically and operationally competitive with surface gasifiers. The results of the Rawlins UCG-SDB field test program suggest that the process can compete with more conventional sources of synthesis gas on an economic basis. The SDB process mechanism has several advantages over the horizontal process and performs in a fashion similar to surface packed bed reactors. The oxygen requirements for the process are quite low and the degree of process control observed at Rawlins ismore » very attractive.« less

Method for generating methane from a carbonaceous feedstock

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snyder, Seth W.; Urgun-Demirtas, Meltem; Shen, Yanwen

The present invention provides a method for generating methane from a carbonaceous feedstock with simultaneous in situ sequestration of carbon dioxide to afford a biogas comprising at least 85 percent by volume methane, the method comprising anaerobically incubating a particulate additive in contact with a carbonaceous feedstock in a neutral or alkaline aqueous culture medium containing a culture of methanogenic consortia and collecting methane generated therefrom. The additive comprises at least one material selected from a biochar, an ash produced by gasification or combustion of a carbonaceous material, a black carbon soil, and a Terra Preta soil.

Geomechanical Analysis of Underground Coal Gasification Reactor Cool Down for Subsequent CO2 Storage

NASA Astrophysics Data System (ADS)

Sarhosis, Vasilis; Yang, Dongmin; Kempka, Thomas; Sheng, Yong

2013-04-01

Underground coal gasification (UCG) is an efficient method for the conversion of conventionally unmineable coal resources into energy and feedstock. If the UCG process is combined with the subsequent storage of process CO2 in the former UCG reactors, a near-zero carbon emission energy source can be realised. This study aims to present the development of a computational model to simulate the cooling process of UCG reactors in abandonment to decrease the initial high temperature of more than 400 °C to a level where extensive CO2 volume expansion due to temperature changes can be significantly reduced during the time of CO2 injection. Furthermore, we predict the cool down temperature conditions with and without water flushing. A state of the art coupled thermal-mechanical model was developed using the finite element software ABAQUS to predict the cavity growth and the resulting surface subsidence. In addition, the multi-physics computational software COMSOL was employed to simulate the cavity cool down process which is of uttermost relevance for CO2 storage in the former UCG reactors. For that purpose, we simulated fluid flow, thermal conduction as well as thermal convection processes between fluid (water and CO2) and solid represented by coal and surrounding rocks. Material properties for rocks and coal were obtained from extant literature sources and geomechanical testings which were carried out on samples derived from a prospective demonstration site in Bulgaria. The analysis of results showed that the numerical models developed allowed for the determination of the UCG reactor growth, roof spalling, surface subsidence and heat propagation during the UCG process and the subsequent CO2 storage. It is anticipated that the results of this study can support optimisation of the preparation procedure for CO2 storage in former UCG reactors. The proposed scheme was discussed so far, but not validated by a coupled numerical analysis and if proved to be applicable it could provide a significant optimisation of the UCG process by means of CO2 storage efficiency. The proposed coupled UCG-CCS scheme allows for meeting EU targets for greenhouse gas emissions and increases the coal yield otherwise impossible to exploit.

Influence of operating conditions on the air gasification of dry refinery sludge in updraft gasifier

NASA Astrophysics Data System (ADS)

Ahmed, R.; Sinnathambi, C. M.

2013-06-01

In the present work, details of the equilibrium modeling of dry refinery sludge (DRS) are presented using ASPEN PLUS Simulator in updraft gasifier. Due to lack of available information in the open journal on refinery sludge gasification using updraft gasifier, an evaluate for its optimum conditions on gasification is presented in this paper. For this purpose a Taguchi Orthogonal array design, statistical software is applied to find optimum conditions for DRS gasification. The goal is to identify the most significant process variable in DRS gasification conditions. The process variables include; oxidation zone temperature, equivalent ratio, operating pressure will be simulated and examined. Attention was focused on the effect of optimum operating conditions on the gas composition of H2 and CO (desirable) and CO2 (undesirable) in terms of mass fraction. From our results and finding it can be concluded that the syngas (H2 & CO) yield in term of mass fraction favors high oxidation zone temperature and at atmospheric pressure while CO2 acid gas favor at a high level of equivalent ratio as well as air flow rate favoring towards complete combustion.

Performance and Characteristics of a Cyclone Gasifier for Gasification of Sawdust

NASA Astrophysics Data System (ADS)

Azman Miskam, Muhamad; Zainal, Z. A.; Idroas, M. Y.

The performance and characteristics of a cyclone gasifier for gasification of sawdust has been studied and evaluated. The system applied a technique to gasify sawdust through the concept of cyclonic motion driven by air injected at atmospheric pressure. This study covers the results obtained for gasification of ground sawdust from local furniture industries with size distribution ranging from 0.25 to 1 mm. It was found that the typical wall temperature for initiating stable gasification process was about 400°C. The heating value of producer gas was about 3.9 MJ m-3 that is sufficient for stable combustion in a dual-fuel engine generator. The highest thermal output from the cyclone gasifier was 57.35 kWT. The highest value of mass conversion efficiency and enthalpy balance were 60 and 98.7%, respectively. The highest efficiency of the cyclone gasifier obtained was 73.4% and this compares well with other researchers. The study has identified the optimum operational condition for gasifying sawdust in a cyclone gasifier and made conclusions as to how the steady gasification process can be achieved.

Noble-metal-free bimetallic alloy nanoparticle-catalytic gasification of phenol in supercritical water

DOE PAGES

Jia, Lijuan; Yu, Jiangdong; Chen, Yuan; ...

2017-08-01

The exploration of non-noble-metal catalysts for high efficiency gasification of biomass in supercritical water (SCW) is of great significance for the sustainable development. A series of Ni–M (M = Co or Zn) bimetallic nanoparticles supported on graphitized carbon black were synthesized and examined as catalysts for gasification of phenol in SCW. We found that a nearly complete gasification of phenol can be achieved even at a low temperature of 450 °C with the bimetallic nanoparticles catalysts. Kinetic study indicated the activation energy for phenol gasification were 20.4 ± 2.6 and 43.6 ± 2.6 kJ/mol for Ni20Zn15 and Ni20Co15 catalyst, respectively.more » Furthermore, XRD, XPS and TEM were performed to characterize the catalysts and the results showed the formation of NiCo and NiZn alloy phase. Catalyst recycling experiments were also conducted to evaluate the stability of the catalysts. The characterization of used catalysts suggest that the severe agglomeration of nanoparticles leads to the decrease in catalytic activity.« less

Noble-metal-free bimetallic alloy nanoparticle-catalytic gasification of phenol in supercritical water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jia, Lijuan; Yu, Jiangdong; Chen, Yuan

The exploration of non-noble-metal catalysts for high efficiency gasification of biomass in supercritical water (SCW) is of great significance for the sustainable development. A series of Ni–M (M = Co or Zn) bimetallic nanoparticles supported on graphitized carbon black were synthesized and examined as catalysts for gasification of phenol in SCW. We found that a nearly complete gasification of phenol can be achieved even at a low temperature of 450 °C with the bimetallic nanoparticles catalysts. Kinetic study indicated the activation energy for phenol gasification were 20.4 ± 2.6 and 43.6 ± 2.6 kJ/mol for Ni20Zn15 and Ni20Co15 catalyst, respectively.more » Furthermore, XRD, XPS and TEM were performed to characterize the catalysts and the results showed the formation of NiCo and NiZn alloy phase. Catalyst recycling experiments were also conducted to evaluate the stability of the catalysts. The characterization of used catalysts suggest that the severe agglomeration of nanoparticles leads to the decrease in catalytic activity.« less

Desorption in Mass Spectrometry.

PubMed

Usmanov, Dilshadbek Tursunbayevich; Ninomiya, Satoshi; Chen, Lee Chuin; Saha, Subhrakanti; Mandal, Mridul Kanti; Sakai, Yuji; Takaishi, Rio; Habib, Ahsan; Hiraoka, Kenzo; Yoshimura, Kentaro; Takeda, Sen; Wada, Hiroshi; Nonami, Hiroshi

2017-01-01

In mass spectrometry, analytes must be released in the gas phase. There are two representative methods for the gasification of the condensed samples, i.e. , ablation and desorption. While ablation is based on the explosion induced by the energy accumulated in the condensed matrix, desorption is a single molecular process taking place on the surface. In this paper, desorption methods for mass spectrometry developed in our laboratory: flash heating/rapid cooling, Leidenfrost phenomenon-assisted thermal desorption (LPTD), solid/solid friction, liquid/solid friction, electrospray droplet impact (EDI) ionization/desorption, and probe electrospray ionization (PESI), will be described. All the methods are concerned with the surface and interface phenomena. The concept of how to desorb less-volatility compounds from the surface will be discussed.

Assessment of advanced coal gasification processes

NASA Technical Reports Server (NTRS)

Mccarthy, J.; Ferrall, J.; Charng, T.; Houseman, J.

1981-01-01

A technical assessment of the following advanced coal gasification processes is presented: high throughput gasification (HTG) process; single stage high mass flux (HMF) processes; (CS/R) hydrogasification process; and the catalytic coal gasification (CCG) process. Each process is evaluated for its potential to produce synthetic natural gas from a bituminous coal. Key similarities, differences, strengths, weaknesses, and potential improvements to each process are identified. The HTG and the HMF gasifiers share similarities with respect to: short residence time (SRT), high throughput rate, slagging, and syngas as the initial raw product gas. The CS/R hydrogasifier is also SRT, but is nonslagging and produces a raw gas high in methane content. The CCG gasifier is a long residence time, catalytic, fluidbed reactor producing all of the raw product methane in the gasifier.

Conceptual design study of a coal gasification combined-cycle powerplant for industrial cogeneration

NASA Astrophysics Data System (ADS)

Bloomfield, H. S.; Nelson, S. G.; Straight, H. F.; Subramaniam, T. K.; Winklepleck, R. G.

1981-03-01

A conceptual design study was conducted to assess technical feasibility, environmental characteristics, and economics of coal gasification. The feasibility of a coal gasification combined cycle cogeneration powerplant was examined in response to energy needs and to national policy aimed at decreasing dependence on oil and natural gas. The powerplant provides the steam heating and baseload electrical requirements while serving as a prototype for industrial cogeneration and a modular building block for utility applications. The following topics are discussed: (1) screening of candidate gasification, sulfur removal and power conversion components; (2) definition of a reference system; (3) quantification of plant emissions and waste streams; (4) estimates of capital and operating costs; and (5) a procurement and construction schedule. It is concluded that the proposed powerplant is technically feasible and environmentally superior.

Conceptual design study of a coal gasification combined-cycle powerplant for industrial cogeneration

NASA Technical Reports Server (NTRS)

Bloomfield, H. S.; Nelson, S. G.; Straight, H. F.; Subramaniam, T. K.; Winklepleck, R. G.

1981-01-01

A conceptual design study was conducted to assess technical feasibility, environmental characteristics, and economics of coal gasification. The feasibility of a coal gasification combined cycle cogeneration powerplant was examined in response to energy needs and to national policy aimed at decreasing dependence on oil and natural gas. The powerplant provides the steam heating and baseload electrical requirements while serving as a prototype for industrial cogeneration and a modular building block for utility applications. The following topics are discussed: (1) screening of candidate gasification, sulfur removal and power conversion components; (2) definition of a reference system; (3) quantification of plant emissions and waste streams; (4) estimates of capital and operating costs; and (5) a procurement and construction schedule. It is concluded that the proposed powerplant is technically feasible and environmentally superior.

Energy Conversion Alternatives Study (ECAS), General Electric Phase 1. Volume 3: Energy conversion subsystems and components. Part 3: Gasification, process fuels, and balance of plant

NASA Technical Reports Server (NTRS)

Boothe, W. A.; Corman, J. C.; Johnson, G. G.; Cassel, T. A. V.

1976-01-01

Results are presented of an investigation of gasification and clean fuels from coal. Factors discussed include: coal and coal transportation costs; clean liquid and gas fuel process efficiencies and costs; and cost, performance, and environmental intrusion elements of the integrated low-Btu coal gasification system. Cost estimates for the balance-of-plant requirements associated with advanced energy conversion systems utilizing coal or coal-derived fuels are included.

Addition to the Lewis Chemical Equilibrium Program to allow computation from coal composition data

NASA Technical Reports Server (NTRS)

Sevigny, R.

1980-01-01

Changes made to the Coal Gasification Project are reported. The program was developed by equilibrium combustion in rocket engines. It can be applied directly to the entrained flow coal gasification process. The particular problem addressed is the reduction of the coal data into a form suitable to the program, since the manual process is involved and error prone. A similar problem in relating the normal output of the program to parameters meaningful to the coal gasification process is also addressed.

The applicability of the catalytic wet-oxidation to CELSS

NASA Technical Reports Server (NTRS)

Takahashi, Y.; Nitta, K.; Ohya, H.; Oguchi, M.

1987-01-01

The wet oxidation catalysis of Au, Pd, Pt, Rh or Ru on a ceramic honeycomb carrier was traced in detail by 16 to 20 repetitive batch tests each. As a result, Pt or Pd on a honeycomb carrier was shown to catalyze complete nitrogen gasification as N2. Though the catalysts which realize both complete nitrogen gasification and complete oxidation could not be found, the Ru+Rh catalyst was found to be most promising. Ru honeycomb catalyzed both nitrification and nitrogen gasification.

Effect of sewage sludge content on gas quality and solid residues produced by cogasification in an updraft gasifier

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seggiani, Maurizia, E-mail: m.seggiani@diccism.unipi.it; Puccini, Monica, E-mail: m.puccini@diccism.unipi.it; Raggio, Giovanni, E-mail: g.raggio@tiscali.it

2012-10-15

Highlights: Black-Right-Pointing-Pointer Cogasification of sewage sludge with wood pellets in updraft gasifier was analysed. Black-Right-Pointing-Pointer The effects of sewage sludge content on the gasification process were examined. Black-Right-Pointing-Pointer Sewage sludge addition up to 30 wt.% reduces moderately the process performance. Black-Right-Pointing-Pointer At high sewage sludge content slagging and clinker formation occurred. Black-Right-Pointing-Pointer Solid residues produced resulted acceptable at landfills for non-hazardous waste. - Abstract: In the present work, the gasification with air of dehydrated sewage sludge (SS) with 20 wt.% moisture mixed with conventional woody biomass was investigated using a pilot fixed-bed updraft gasifier. Attention was focused on the effectmore » of the SS content on the gasification performance and on the environmental impact of the process. The results showed that it is possible to co-gasify SS with wood pellets (WPs) in updraft fixed-bed gasification installations. However, at high content of sewage sludge the gasification process can become instable because of the very high ash content and low ash fusion temperatures of SS. At an equivalent ratio of 0.25, compared with wood pellets gasification, the addition of sewage sludge led to a reduction of gas yield in favor of an increase of condensate production with consequent cold gas efficiency decrease. Low concentrations of dioxins/furans and PAHs were measured in the gas produced by SS gasification, well below the limiting values for the exhaust gaseous emissions. NH{sub 3}, HCl and HF contents were very low because most of these compounds were retained in the wet scrubber systems. On the other hand, high H{sub 2}S levels were measured due to high sulfur content of SS. Heavy metals supplied with the feedstocks were mostly retained in gasification solid residues. The leachability tests performed according to European regulations showed that metals leachability was within the limits for landfilling inert residues. On the other hand, sulfate and chloride releases were found to comply with the limits for non-hazardous residues.« less

Catalysts for carbon and coal gasification

DOEpatents

McKee, Douglas W.; Spiro, Clifford L.; Kosky, Philip G.

1985-01-01

Catalyst for the production of methane from carbon and/or coal by means of catalytic gasification. The catalyst compostion containing at least two alkali metal salts. A particulate carbonaceous substrate or carrier is used.

Coal gasification systems engineering and analysis. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1980-01-01

Feasibility analyses and systems engineering studies for a 20,000 tons per day medium Btu (MBG) coal gasification plant to be built by TVA in Northern Alabama were conducted. Major objectives were as follows: (1) provide design and cost data to support the selection of a gasifier technology and other major plant design parameters, (2) provide design and cost data to support alternate product evaluation, (3) prepare a technology development plan to address areas of high technical risk, and (4) develop schedules, PERT charts, and a work breakdown structure to aid in preliminary project planning. Volume one contains a summary of gasification system characterizations. Five gasification technologies were selected for evaluation: Koppers-Totzek, Texaco, Lurgi Dry Ash, Slagging Lurgi, and Babcock and Wilcox. A summary of the trade studies and cost sensitivity analysis is included.

Effect of small-scale biomass gasification at the state of refractory lining the fixed bed reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janša, Jan, E-mail: jan.jansa@vsb.cz; Peer, Vaclav, E-mail: vaclav.peer@vsb.cz; Pavloková, Petra, E-mail: petra.pavlokova@vsb.cz

The article deals with the influence of biomass gasification on the condition of the refractory lining of a fixed bed reactor. The refractory lining of the gasifier is one part of the device, which significantly affects the operational reliability and durability. After removing the refractory lining of the gasifier from the experimental reactor, there was done an assessment how gasification of different kinds of biomass reflected on its condition in terms of the main factors affecting its life. Gasification of biomass is reflected on the lining, especially through sticking at the bottom of the reactor. Measures for prolonging the lifemore » of lining consist in the reduction of temperature in the reactor, in this case, in order to avoid ash fusion biomass which it is difficult for this type of gasifier.« less

Chemical looping coal gasification with calcium ferrite and barium ferrite via solid--solid reactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siriwardane, Ranjani; Riley, Jarrett; Tian, Hanjing

Coal gasification to produce synthesis gas by chemical looping was investigated with two oxygen carriers, barium ferrite (BaFe2O4) and calcium ferrite (CaFe2O4). Thermo-gravimetric analysis (TGA) and fixed-bed flow reactor data indicated that a solid–solid interaction occurred between oxygen carriers and coal to produce synthesis gas. Both thermodynamic analysis and experimental data indicated that BaFe2O4 and CaFe2O4 have high reactivity with coal but have a low reactivity with synthesis gas, which makes them very attractive for the coal gasification process. Adding steam increased the production of hydrogen (H2) and carbon monoxide (CO), but carbon dioxide (CO2) remained low because these oxygenmore » carriers have minimal reactivity with H2 and CO. Therefore, the combined steam–oxygen carrier produced the highest quantity of synthesis gas. It appeared that neither the water–gas shift reaction nor the water splitting reaction promoted additional H2 formation with the oxygen carriers when steam was present. Wyodak coal, which is a sub-bituminous coal, had the best gasification yield with oxygen carrier–steam while Illinois #6 coal had the lowest. The rate of gasification and selectivity for synthesis gas production was significantly higher when these oxygen carriers were present during steam gasification of coal. The rates and synthesis gas yields during the temperature ramps of coal–steam with oxygen carriers were better than with gaseous oxygen.« less

Thermodynamics Analysis of Refinery Sludge Gasification in Adiabatic Updraft Gasifier

PubMed Central

Ahmed, Reem; Sinnathambi, Chandra M.; Eldmerdash, Usama; Subbarao, Duvvuri

2014-01-01

Limited information is available about the thermodynamic evaluation for biomass gasification process using updraft gasifier. Therefore, to minimize errors, the gasification of dry refinery sludge (DRS) is carried out in adiabatic system at atmospheric pressure under ambient air conditions. The objectives of this paper are to investigate the physical and chemical energy and exergy of product gas at different equivalent ratios (ER). It will also be used to determine whether the cold gas, exergy, and energy efficiencies of gases may be maximized by using secondary air injected to gasification zone under various ratios (0, 0.5, 1, and 1.5) at optimum ER of 0.195. From the results obtained, it is indicated that the chemical energy and exergy of producer gas are magnified by 5 and 10 times higher than their corresponding physical values, respectively. The cold gas, energy, and exergy efficiencies of DRS gasification are in the ranges of 22.9–55.5%, 43.7–72.4%, and 42.5–50.4%, respectively. Initially, all 3 efficiencies increase until they reach a maximum at the optimum ER of 0.195; thereafter, they decline with further increase in ER values. The injection of secondary air to gasification zone is also found to increase the cold gas, energy, and exergy efficiencies. A ratio of secondary air to primary air of 0.5 is found to be the optimum ratio for all 3 efficiencies to reach the maximum values. PMID:24672368

A high temperature drop-tube and packed-bed solar reactor for continuous biomass gasification

NASA Astrophysics Data System (ADS)

Bellouard, Quentin; Abanades, Stéphane; Rodat, Sylvain; Dupassieux, Nathalie

2017-06-01

Biomass gasification is an attractive process to produce high-value syngas. Utilization of concentrated solar energy as the heat source for driving reactions increases the energy conversion efficiency, saves biomass resource, and eliminates the needs for gas cleaning and separation. A high-temperature tubular solar reactor combining drop tube and packed bed concepts was used for continuous solar-driven gasification of biomass. This 1 kW reactor was experimentally tested with biomass feeding under real solar irradiation conditions at the focus of a 2 m-diameter parabolic solar concentrator. Experiments were conducted at temperatures ranging from 1000°C to 1400°C using wood composed of a mix of pine and spruce (bark included) as biomass feedstock. The aim of this study was to demonstrate the feasibility of syngas production in this reactor concept and to prove the reliability of continuous biomass gasification processing using solar energy. The study first consisted of a parametric study of the gasification conditions to obtain an optimal gas yield. The influence of temperature and oxidizing agent (H2O or CO2) on the product gas composition was investigated. The study then focused on solar gasification during continuous biomass particle injection for demonstrating the feasibility of a continuous process. Regarding the energy conversion efficiency of the lab scale reactor, energy upgrade factor of 1.21 and solar-to-fuel thermochemical efficiency up to 28% were achieved using wood heated up to 1400°C.

Tar Management and Recycling in Biomass Gasification and Syngas Purification

NASA Astrophysics Data System (ADS)

McCaffrey, Zach

Removal of tars is critical to the design and operation of biomass gasification systems as most syngas utilization processing equipment (e.g. internal combustion engines, gas turbines, fuel cells, and liquid fuel synthesis reactors) have a low tolerance for tar. Capturing and disposal of tar is expensive due to equipment costs, high hazardous waste disposal costs where direct uses cannot be found, and system energy losses incurred. Water scrubbing is an existing technique commonly used in gasification plants to remove contaminants and tar; however using water as the absorbent is non-ideal as tar compounds have low or no water solubility. Hydrophobic solvents can improve scrubber performance and this study evaluated tar solubility in selected solvents using slip-streams of untreated syngas from a laboratory fluidized bed reactor operated on almond composite feedstock using both air and steam gasification. Tar solubility was compared with Hansen's solubility theory to examine the extent to which the tar removal can be predicted. As collection of tar without utilization leads to a hazardous waste problem, the study investigated the effects of recycling tars back into the gasifier for destruction. Prior to experiments conducted on tar capture and recycle, characterizations of the air and steam gasification of the almond composite mix were made. This work aims to provide a better understanding of tar collection and solvent selection for wet scrubbers, and to provide information for designing improved tar management systems for biomass gasification.

Soil biochar amendments: type and dose effects

NASA Astrophysics Data System (ADS)

Ojeda, G.; Domene, X.; Mattana, S.; Sousa, J. P.; Ortiz, O.; Andres, P.; Alcañiz, J. M.

2012-04-01

Biochar is an organic material produced via the pyrolysis of C-based biomass, which is increasingly being recognized by scientists and policy makers for its potential role in carbon sequestration, reducing greenhouse gas emissions, waste mitigation, and as a soil amendment. Recent studies indicated that biochar improves soil fertility through its positive influence on physical-chemical properties, since not only improves water retention, aggregation and permeability, but its high charge density can also hold large amounts of nutrients, increasing crop production. However, it was observed that combustion temperature could affects the degree of aromaticity and the size of aromatic sheets, which in turns determine short-term mineralization rates. To reconcile the different decompasibility observations of biochar, it has sugested that physical protection and interactions with soil minerals play a significant part in biochar stability. In this context, it has initiated one pilot studies which aims to assess the effects of biochar application on physical and chemical properties of agricultural soil under Mediterranean conditions, such as changes in aggregate formation, intra-aggregate carbon sequestration and chemistry of soil water. In the present study, different clases of biochar produced from fast, slow and gasification pyrolisis of vegetal (pine, poplar) and dried sludge biomass, were applied at 1% of biochar-C to mesocosmos of an agricultural soil. Preliminary, it must be pointed out that slow and gasification pyrolisis changes the proportion of particles < 2 mm in diameter, from 10% (original materials) to almost 100%. In contrast, slow pyrolisis not modifies significantly biochar granulometry. As a consequence, bulk density of poplar and pine splinters decreases after fast pyrolisis. Regarding to organic carbon contents of biochar, all biochars obtained from plant biomass presented percentagens of total organic carbon (TOC) between 70 - 90%, while biochar obtained from dried sludge by slow pyrolisis has a TOC around of 22%. On the other hand, pH values of biochar depends of the type of pyrolisis as observed in the biochar obtained from poplar biomass, where pH of slow pyrolisis < fast pyrolisis < gasification pyrolisis. When soil aggregate stability was tested, it was observed that biochars from pine biomass obtained by slow and fast pyrolisis trend to increase the water-stable soil aggregates, while the biochars from poplar and thermally-dreid sludge obtained by slow pyrolisis and from pine biomass obtained by gasification trend to the contrary. These differences were not explained by TOC contents or bulk density of bichars, probably because specific resistence to slaking and wettability of each biochar. At least, when measuring pH values of water where soil aggregates were immersed during soil aggregate stability test, it was observed that biochars from thermally-dried sludge obtained by slow pyrolisis and from pine biomass obtained by gasification pyrolisis increased water pH, which corresponded with high pH values of both biochars. In general, increases in the percentage of water-stable soil aggregates corresponded with increases in water pH values, except in the case of biochar from pine biomass obtained by slow pyrolisis.

Hybrid Technology of Hard Coal Mining from Seams Located at Great Depths

NASA Astrophysics Data System (ADS)

Czaja, Piotr; Kamiński, Paweł; Klich, Jerzy; Tajduś, Antoni

2014-10-01

Learning to control fire changed the life of man considerably. Learning to convert the energy derived from combustion of coal or hydrocarbons into another type of energy, such as steam pressure or electricity, has put him on the path of scientific and technological revolution, stimulating dynamic development. Since the dawn of time, fossil fuels have been serving as the mankind's natural reservoir of energy in an increasingly great capacity. A completely incomprehensible refusal to use fossil fuels causes some local populations, who do not possess a comprehensive knowledge of the subject, to protest and even generate social conflicts as an expression of their dislike for the extraction of minerals. Our times are marked by the search for more efficient ways of utilizing fossil fuels by introducing non-conventional technologies of exploiting conventional energy sources. During apartheid, South Africa demonstrated that cheap coal can easily satisfy total demand for liquid and gaseous fuels. In consideration of current high prices of hydrocarbon media (oil and gas), gasification or liquefaction of coal seems to be the innovative technology convergent with contemporary expectations of both energy producers as well as environmentalists. Known mainly from literature reports, underground coal gasification technologies can be brought down to two basic methods: - shaftless method - drilling, in which the gasified seam is uncovered using boreholes drilled from the surface, - shaft method, in which the existing infrastructure of underground mines is used to uncover the seams. This paper presents a hybrid shaft-drilling approach to the acquisition of primary energy carriers (methane and syngas) from coal seams located at great depths. A major advantage of this method is the fact that the use of conventional coal mining technology requires the seams located at great depths to be placed on the off-balance sheet, while the hybrid method of underground gasification enables them to become a source of additional energy for the economy. It should be noted, however, that the shaft-drilling method cannot be considered as an alternative to conventional methods of coal extraction, but rather as a complementary and cheaper way of utilizing resources located almost beyond the technical capabilities of conventional extraction methods due to the associated natural hazards and high costs of combating them. This article presents a completely different approach to the issue of underground coal gasification. Repurposing of the already fully depreciated mining infrastructure for the gasification process may result in a large value added of synthesis gas production and very positive economic effect.

Assessment of Tree Leaves Flakes Mixed with Crude Glycerol as a Bioenergy Source

PubMed Central

Hilal-AlNaqbi, Ali; Al-Omari, Salah B.; Selim, Mohamed Y. E.

2016-01-01

The gasification and combustion of dry tree leaves and the cogasification of dry tree leaves soaking crude glycerol were studied experimentally. An updraft fixed bed gasification and combustion system was built. The operation was conducted at different air to fuel ratios. Results show more stable combustion and more effective heat transfer to furnace walls for the cases when tree leaves flakes are mixed with 20 percent (on mass basis) of crude glycerol, as compared with the case when only dry tree leaves are used as fuel. TGA analysis was also conducted for the two fuels used under both air and nitrogen environments. For the crude glycerol, four phases of pyrolysis and gasification were noticed under either of the two surrounding gaseous media (air or nitrogen). For the dry tree leaves, the pyrolysis under nitrogen shows only a simple smooth pyrolysis and gasification curve without showing the different distinct phases that were otherwise identified when the pyrolysis is conducted under air environment. Moreover, the air TGA results lead to more gasification due to the char oxidation at high temperatures. DTG results are also presented and discussed. PMID:27413749

Fuzzy Bayesian Network-Bow-Tie Analysis of Gas Leakage during Biomass Gasification

PubMed Central

Yan, Fang; Xu, Kaili; Yao, Xiwen; Li, Yang

2016-01-01

Biomass gasification technology has been rapidly developed recently. But fire and poisoning accidents caused by gas leakage restrict the development and promotion of biomass gasification. Therefore, probabilistic safety assessment (PSA) is necessary for biomass gasification system. Subsequently, Bayesian network-bow-tie (BN-bow-tie) analysis was proposed by mapping bow-tie analysis into Bayesian network (BN). Causes of gas leakage and the accidents triggered by gas leakage can be obtained by bow-tie analysis, and BN was used to confirm the critical nodes of accidents by introducing corresponding three importance measures. Meanwhile, certain occurrence probability of failure was needed in PSA. In view of the insufficient failure data of biomass gasification, the occurrence probability of failure which cannot be obtained from standard reliability data sources was confirmed by fuzzy methods based on expert judgment. An improved approach considered expert weighting to aggregate fuzzy numbers included triangular and trapezoidal numbers was proposed, and the occurrence probability of failure was obtained. Finally, safety measures were indicated based on the obtained critical nodes. The theoretical occurrence probabilities in one year of gas leakage and the accidents caused by it were reduced to 1/10.3 of the original values by these safety measures. PMID:27463975

Characteristics of Catalytic Gasification of Natural Coke with H2O in a Fluidized Bed

NASA Astrophysics Data System (ADS)

Lin, L. S.; Zhao, C. S.; Wang, S.; Zhu, G.; Xiang, W. G.

The experimental investigation on gasification characteristics of natural coke from Peicheng, Jiangsu with steam were conducted in a fluidized bed gasifier setup. The effects of several parameters, in terms of the catalyst type, the catalyst mixed manner and the dosage of catalyst over coke on the yield, the components, the heating value of fuel gas and the carbon conversion rate were examined. Results indicate that the fluidized bed gasification technology could overcome the shortcomings of natural coke. Ca-, Fe- and Cu-based nitrates could improve the gasification reaction effectively with a little difference, they could be listed in a descending sequence as follows: Cu-based>Fe-based>Ca-based according to their catalytic effect. The influences of Fe/Ca ratio and Cu/Ca ratio on gasification are similar, gas yield, carbon conversion rate and gas heating value per hour increase as Fe/Ca ratio or Cu/Ca ratio increases, but all of them go up first and then drop with decrease in Fe/Cu ratio. When the dosage of Ca-, Fe- and Cu-based nitrates mixed with the ratio of Ca/Fe/Cu= 10/35/55 is 3%, the best catalytic effect is achieved.

Gasification of algal biomass (Cladophora glomerata L.) with CO2/H2O/O2 in a circulating fluidized bed.

PubMed

Ebadi, Abdol Ghaffar; Hisoriev, Hikmat

2017-11-28

Gasification is one of the most important thermochemical routes to produce both synthesis gas (syngas) and chars. The quality of produced syngas wieldy depends on the operating conditions (temperature, residence time, heating rate, and gasifying agent), hydrodynamic properties of gasifier (particle size, minimum fluidization velocity, and gasifier size), and type of feedstock (coal, biomass, oil, and municipal solid wastes). In the present study, simulation of syngas production via circulating fluidized bed (CFB) gasification of algal biomass (Cladophora glomerata L.) at different gasifying agents and particle sizes was carried out, using Aspen Plus simulator. The model which has been validated by using experimental data of the technical literature was used to evaluate the influence of operating conditions on gas composition and performance parameters. The results show that biomass gasification using pure oxygen as the gasification agent has great potential to improve the caloric value of produced gas and performance indicators. It was also found that the produced gas caloric value, syngas yield, and performance parameters (CCE and CGE) increase with reaction temperature but are inversely proportional to the biomass particle size.

A Novel Study of Methane-Rich Gas Reforming to Syngas and Its Kinetics over Semicoke Catalyst

PubMed Central

Zhang, Guojie; Su, Aiting; Qu, Jiangwen; Du, Yannian

2014-01-01

A small-size gasification unit is improved through process optimization to simulate industrial United Gas Improvement Company gasification. It finds that the reaction temperature has important impacts on semicoke catalyzed methane gas mixture. The addition of water vapor can enhance the catalytic activity of reforming, which is due to the fact that addition of water vapor not only removes carbon deposit produced in the reforming and gasification reaction processes, but also participates in gasification reaction with semicoke to generate some active oxygen-containing functional groups. The active oxygen-containing functional groups provide active sites for carbon dioxide reforming of methane, promoting the reforming reaction. It also finds that the addition of different proportions of methane-rich gas can yield synthesis gas with different H2/CO ratio. The kinetics study shows that the semicoke can reduce the activation energy of the reforming reaction and promote the occurrence of the reforming reaction. The kinetics model of methane reforming under the conditions of steam gasification over semicoke is as follows: k-=5.02×103·pCH40.71·pH20.26·exp(−74200/RT). PMID:24959620

Determination of the fire hazards of mine materials using a radiant panel.

PubMed

Harteis, S P; Litton, C D; Thomas, R A

2016-01-01

The objective of this study was to develop a laboratory-scale method to rank the ignition and fire hazards of commonly used underground mine materials and to eliminate the need for the expensive large-scale tests that are currently being used. A radiant-panel apparatus was used to determine the materials' relevant thermal characteristics: time to ignition, critical heat flux for ignition, heat of gasification, and mass-loss rate. Three thermal parameters, TRP , TP1 and TP4 , were derived from the data, then developed and subsequently used to rank the combined ignition and fire hazards of the combustible materials from low hazard to high hazard. The results compared favorably with the thermal and ignition hazards of similar materials reported in the literature and support this approach as a simpler one for quantifying these combustible hazards.

A Burning Rate Emulator (BRE) for Study in Microgravity

NASA Technical Reports Server (NTRS)

Markan, A.; Sunderland, P. B.; Quintiere, J. G.; DeRis, J.; Stocker, D. P.

2015-01-01

A gas-fueled burner, the Burning Rate Emulator (BRE), is used to emulate condensed-phase fuel flames. The design has been validated to easily measure the burning behavior of condensed-phase fuels by igniting a controlled stream of gas fuel and diluent. Four properties, including the heat of combustion, the heat of gasification, the surface temperature, and the laminar smoke point, are assumed to be sufficient to define the steady burning rate of a condensed-phase fuel. The heat of gasification of the fuel is determined by measuring the heat flux and the fuel flow rate. Microgravity BRE tests in the NASA 5.2 s drop facility have examined the burning of pure methane and ethylene (pure and 50 in N2 balance). Fuel flow rates, chamber oxygen concentration and initial pressure have been varied. Two burner sizes, 25 and 50 mm respectively, are chosen to examine the nature of initial microgravity burning. The tests reveal bubble-like flames that increase within the 5.2s drop but the heat flux received from the flame appears to asymptotically approach steady state. Portions of the methane flames appear to locally detach and extinguish at center, while its shape remains fixed, but growing. The effective heat of gasification is computed from the final measured net heat flux and the fuel flow rate under the assumption of an achieved steady burning. Heat flux (or mass flux) and flame position are compared with stagnant layer burning theory. The analysis offers the prospect of more complete findings from future longer duration ISS experiments.

Combining plasma gasification and solid oxide cell technologies in advanced power plants for waste to energy and electric energy storage applications.

PubMed

Perna, Alessandra; Minutillo, Mariagiovanna; Lubrano Lavadera, Antonio; Jannelli, Elio

2018-03-01

The waste to energy (WtE) facilities and the renewable energy storage systems have a strategic role in the promotion of the "eco-innovation", an emerging priority in the European Union. This paper aims to propose advanced plant configurations in which waste to energy plants and electric energy storage systems from intermittent renewable sources are combined for obtaining more efficient and clean energy solutions in accordance with the "eco-innovation" approach. The advanced plant configurations consist of an electric energy storage (EES) section based on a solid oxide electrolyzer (SOEC), a waste gasification section based on the plasma technology and a power generation section based on a solid oxide fuel cell (SOFC). The plant configurations differ for the utilization of electrolytic hydrogen and oxygen in the plasma gasification section and in the power generation section. In the first plant configuration IAPGFC (Integrated Air Plasma Gasification Fuel Cell), the renewable oxygen enriches the air stream, that is used as plasma gas in the gasification section, and the renewable hydrogen is used to enrich the anodic stream of the SOFC in the power generation section. In the second plant configuration IHPGFC (Integrated Hydrogen Plasma Gasification Fuel Cell) the renewable hydrogen is used as plasma gas in the plasma gasification section, and the renewable oxygen is used to enrich the cathodic stream of the SOFC in the power generation section. The analysis has been carried out by using numerical models for predicting and comparing the systems performances in terms of electric efficiency and capability in realizing the waste to energy and the electric energy storage of renewable sources. Results have highlighted that the electric efficiency is very high for all configurations (35-45%) and, thanks to the combination with the waste to energy technology, the storage efficiencies are very attractive (in the range 72-92%). Copyright © 2017 Elsevier Ltd. All rights reserved.

Supercritical water gasification of landfill leachate for hydrogen production in the presence and absence of alkali catalyst.

PubMed

Weijin, Gong; Binbin, Li; Qingyu, Wang; Zuohua, Huang; Liang, Zhao

2018-03-01

Gasification of landfill leachate in supercritical water using batch-type reactor is investigated. Alkali such as NaOH, KOH, K 2 CO 3 , Na 2 CO 3 is used as catalyst. The effect of temperature (380-500 °C), retention time (5-25 min), landfill leachate concentration (1595 mg L -1 -15,225 mg L -1 ), catalyst adding amount (1-10 wt%) on hydrogen mole fraction, hydrogen yield, carbon gasification rate, COD, TOC, TN removal efficiency are investigated. The results showed that gaseous products mainly contained hydrogen, methane, carbon dioxide and carbon monoxide without addition of catalyst. However, the main gaseous products are hydrogen and methane with addition of NaOH, KOH, K 2 CO 3 , Na 2 CO 3 . In the absence of alkali catalyst, the effect of temperature on landfill leachate gasification is positive. Hydrogen mole fraction, hydrogen yield, carbon gasification ratio increase with temperature, which maximum value being 55.6%, 107.15 mol kg -1 , 71.96% is obtained at 500 °C, respectively. Higher raw landfill leachate concentration leads to lower hydrogen production and carbon gasification rate. The suitable retention time is suggested to be 15 min for higher hydrogen production and carbon gasification rate. COD, TOC and TN removal efficiency also increase with increase of temperature, decrease of landfill leachate concentration. In the presence of catalyst, the hydrogen production is obviously promoted by addition of alkali catalyst. the effect of catalysts on hydrogen production is in the following order: NaOH ＞ KOH ＞ Na 2 CO 3  ＞ K 2 CO 3 . The maximum hydrogen mole fraction and hydrogen yield being 74.40%, 70.05 mol kg -1 is obtained with adding amount of 5 wt% NaOH at 450 °C, 28 MPa, 15 min. Copyright © 2017. Published by Elsevier Ltd.

Biomass thermochemical gasification: Experimental studies and modeling

NASA Astrophysics Data System (ADS)

Kumar, Ajay

The overall goals of this research were to study the biomass thermochemical gasification using experimental and modeling techniques, and to evaluate the cost of industrial gas production and combined heat and power generation. This dissertation includes an extensive review of progresses in biomass thermochemical gasification. Product gases from biomass gasification can be converted to biopower, biofuels and chemicals. However, for its viable commercial applications, the study summarizes the technical challenges in the gasification and downstream processing of product gas. Corn stover and dried distillers grains with solubles (DDGS), a non-fermentable byproduct of ethanol production, were used as the biomass feedstocks. One of the objectives was to determine selected physical and chemical properties of corn stover related to thermochemical conversion. The parameters of the reaction kinetics for weight loss were obtained. The next objective was to investigate the effects of temperature, steam to biomass ratio and equivalence ratio on gas composition and efficiencies. DDGS gasification was performed on a lab-scale fluidized-bed gasifier with steam and air as fluidizing and oxidizing agents. Increasing the temperature resulted in increases in hydrogen and methane contents and efficiencies. A model was developed to simulate the performance of a lab-scale gasifier using Aspen Plus(TM) software. Mass balance, energy balance and minimization of Gibbs free energy were applied for the gasification to determine the product gas composition. The final objective was to optimize the process by maximizing the net energy efficiency, and to estimate the cost of industrial gas, and combined heat and power (CHP) at a biomass feedrate of 2000 kg/h. The selling price of gas was estimated to be 11.49/GJ for corn stover, and 13.08/GJ for DDGS. For CHP generation, the electrical and net efficiencies were 37 and 86%, respectively for corn stover, and 34 and 78%, respectively for DDGS. For corn stover, the selling price of electricity was 0.1351/kWh. For DDGS, the selling price of electricity was 0.1287/kWh.

Modeling and Numerical Investigation of the Process of Vapor-Oxygen Gasification of Solid Fuels in a Vertical Flow Reactor Under Pressure

NASA Astrophysics Data System (ADS)

Rokhman, B. B.

2014-09-01

With the use of the developed model, detailed information has been obtained on the working process in a flow reactor with single- and two-stage schemes of vapor-oxygen gasification of coals under a pressure of 3 MPa. The dependence of the ratios of mass flow rates O2/coal and H2O/coal on the type of fuel has been established and their optimal values for the "Shell" process have been found. At a given consumption ratio of gas coal and brown coal of brand B1, the optimum diameters of particles providing minimum combustible loss of the carbon mixture have been determined. It has been found that the content of methane in the syngas in the case of two-stage gasification is much higher than in the case of single-stage gasification.

Wabash River coal gasification repowering project -- first year operation experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Troxclair, E.J.; Stultz, J.

1997-12-31

The Wabash River Coal Gasification Repowering Project (WRCGRP), a joint venture between Destec Energy, Inc. and PSI Energy, Inc., began commercial operation in November of 1995. The Project, selected by the United States Department of Energy (DOE) under the Clean Coal Program (Round IV) represents the largest operating coal gasification combined cycle plant in the world. This Demonstration Project has allowed PSI Energy to repower a 1950`s vintage steam turbine and install a new syngas fired combustion turbine to provide 262 MW (net) of electricity in a clean, efficient manner in a commercial utility setting while utilizing locally mined highmore » sulfur Indiana bituminous coal. In doing so, the Project is also demonstrating some novel technology while advancing the commercialization of integrated coal gasification combined cycle technology. This paper discusses the first year operation experience of the Wabash Project, focusing on the progress towards achievement of the demonstration objectives.« less

Gasification Reaction Characteristics of Ferro-Coke at Elevated Temperatures

NASA Astrophysics Data System (ADS)

Wang, Peng; Zhang, Jian-liang; Gao, Bing

2017-01-01

In this paper, the effects of temperature and atmosphere on the gasification reaction of ferro-coke were investigated in consideration of the actual blast furnace conditions. Besides, the microstructure of the cokes was observed by scanning electron microscope (SEM). It is found that the weight loss of ferro-coke during the gasification reaction is significantly enhanced in the case of increasing either the reaction temperature or the CO2 concentration. Furthermore, compared with the normal type of metallurgical coke, ferro-coke exhibits a higher weight loss when they are gasified at the same temperature or under the same atmosphere. As to the microstructure, inside the reacted ferro-coke are a large amount of pores. Contrary to the normal coke, the proportions of the large-size pores and the through holes are greatly increased after gasification, giving rise to thinner pore walls and hence a degradation in coke strength after reaction (CSR).

Analysis of Hydrogen Generation through Thermochemical Gasification of Coconut Shell Using Thermodynamic Equilibrium Model Considering Char and Tar

PubMed Central

Rupesh, Shanmughom; Muraleedharan, Chandrasekharan; Arun, Palatel

2014-01-01

This work investigates the potential of coconut shell for air-steam gasification using thermodynamic equilibrium model. A thermodynamic equilibrium model considering tar and realistic char conversion was developed using MATLAB software to predict the product gas composition. After comparing it with experimental results the prediction capability of the model is enhanced by multiplying equilibrium constants with suitable coefficients. The modified model is used to study the effect of key process parameters like temperature, steam to biomass ratio, and equivalence ratio on product gas yield, composition, and heating value of syngas along with gasification efficiency. For a steam to biomass ratio of unity, the maximum mole fraction of hydrogen in the product gas is found to be 36.14% with a lower heating value of 7.49 MJ/Nm3 at a gasification temperature of 1500 K and equivalence ratio of 0.15. PMID:27433487

Analysis of Hydrogen Generation through Thermochemical Gasification of Coconut Shell Using Thermodynamic Equilibrium Model Considering Char and Tar.

PubMed

Rupesh, Shanmughom; Muraleedharan, Chandrasekharan; Arun, Palatel

2014-01-01

This work investigates the potential of coconut shell for air-steam gasification using thermodynamic equilibrium model. A thermodynamic equilibrium model considering tar and realistic char conversion was developed using MATLAB software to predict the product gas composition. After comparing it with experimental results the prediction capability of the model is enhanced by multiplying equilibrium constants with suitable coefficients. The modified model is used to study the effect of key process parameters like temperature, steam to biomass ratio, and equivalence ratio on product gas yield, composition, and heating value of syngas along with gasification efficiency. For a steam to biomass ratio of unity, the maximum mole fraction of hydrogen in the product gas is found to be 36.14% with a lower heating value of 7.49 MJ/Nm(3) at a gasification temperature of 1500 K and equivalence ratio of 0.15.

Pyrolysis of coal, biomass and their blends: performance assessment by thermogravimetric analysis.

PubMed

Ferrara, Francesca; Orsini, Alessandro; Plaisant, Alberto; Pettinau, Alberto

2014-11-01

With the aim to support the experimental tests in a gasification pilot plant, the thermal decomposition of coal, biomass and their mixtures has been carried out through a thermogravimetric analysis (TGA) and a simplified kinetic analysis. The TGA of pure fuels indicates the low reactivity of South African coal and the relatively high reactivity of Sardinian Sulcis coal during pyrolysis. Among the tested fuels, biomass (stone pine wood chips) is the most reactive one. These results fully confirm those obtained during the experimental tests in the gasification pilot plant. As for the fuel blends, the analysis shows that the synergic effects between the considered coals and biomass are negligible when they are co-pyrolyzed. The results of the analysis confirm that TGA could be very useful to generally predict the gasification performance and to optimize the experimental campaigns in pilot-scale gasification plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

Process simulation of ethanol production from biomass gasification and syngas fermentation.

PubMed

Pardo-Planas, Oscar; Atiyeh, Hasan K; Phillips, John R; Aichele, Clint P; Mohammad, Sayeed

2017-12-01

The hybrid gasification-syngas fermentation platform can produce more bioethanol utilizing all biomass components compared to the biochemical conversion technology. Syngas fermentation operates at mild temperatures and pressures and avoids using expensive pretreatment processes and enzymes. This study presents a new process simulation model developed with Aspen Plus® of a biorefinery based on a hybrid conversion technology for the production of anhydrous ethanol using 1200tons per day (wb) of switchgrass. The simulation model consists of three modules: gasification, fermentation, and product recovery. The results revealed a potential production of about 36.5million gallons of anhydrous ethanol per year. Sensitivity analyses were also performed to investigate the effects of gasification and fermentation parameters that are keys for the development of an efficient process in terms of energy conservation and ethanol production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization of airborne particles at a high-btu coal-gasification pilot plant.

PubMed

Davidson, C I; Santhanam, S; Stetter, J R; Flotard, R D; Gebert, E

1982-12-01

Airborne particles in fugitive emissions have been measured at a slagging fixed-bed coal-gasification pilot plant using lignite. Sampling was conducted during shutdown operations and opening of the gasifier following an aborted startup. Aerosol collected with a Sierra high-volume impactor was subjected to analysis by gas chromatography, mass spectrometry, and scanning electron microscopy; aerosol collected with an Andersen low-volume impactor was subjected to flameless atomic absorption analysis. The data show that the bulk of the trace organic material is associated with small particles: these data are similar to data on ambient air reported in the literature. Particle morphologies resemble those of fly ash from coal combustion, including smooth spheres, vesicular spheres, and crystalline material. Trace element size distributions are bimodal and resemble data for ambient air. Pb-containing particles are generally submicron, while particles containing Al, Fe, and other crustal species are mostly of supermicron size. Aluminum-based aerosol enrichment factors calculated from the lignite composition show that the composition of the aerosol resembles that of the coal, with the exception of modest enrichments of Mg, Na, As, and Pb in the submicron size range. Aerosol enrichment factors based on the earth's crustal composition are somewhat greater than those based on coal composition for several elements, suggesting potential errors in using crustal enrichment data to investigate chemical fractionation during aerosol formation.

Desorption in Mass Spectrometry

PubMed Central

Usmanov, Dilshadbek Tursunbayevich; Ninomiya, Satoshi; Chen, Lee Chuin; Saha, Subhrakanti; Mandal, Mridul Kanti; Sakai, Yuji; Takaishi, Rio; Habib, Ahsan; Hiraoka, Kenzo; Yoshimura, Kentaro; Takeda, Sen; Wada, Hiroshi; Nonami, Hiroshi

2017-01-01

In mass spectrometry, analytes must be released in the gas phase. There are two representative methods for the gasification of the condensed samples, i.e., ablation and desorption. While ablation is based on the explosion induced by the energy accumulated in the condensed matrix, desorption is a single molecular process taking place on the surface. In this paper, desorption methods for mass spectrometry developed in our laboratory: flash heating/rapid cooling, Leidenfrost phenomenon-assisted thermal desorption (LPTD), solid/solid friction, liquid/solid friction, electrospray droplet impact (EDI) ionization/desorption, and probe electrospray ionization (PESI), will be described. All the methods are concerned with the surface and interface phenomena. The concept of how to desorb less-volatility compounds from the surface will be discussed. PMID:28337398

Enhanced degradation of phenolic compounds in coal gasification wastewater by a novel integration of micro-electrolysis with biological reactor (MEBR) under the micro-oxygen condition.

PubMed

Ma, Weiwei; Han, Yuxing; Xu, Chunyan; Han, Hongjun; Ma, Wencheng; Zhu, Hao; Li, Kun; Wang, Dexin

2018-03-01

The aim of this work was to study an integration of micro-electrolysis with biological reactor (MEBR) for strengthening removal of phenolic compounds in coal gasification wastewater (CGW). The results indicated MEBR achieved high efficiencies in removal of COD and phenolic compounds as well as improvement of biodegradability of CGW under the micro-oxygen condition. The integrated MEBR process was more favorable to improvement of the structural stability of activated sludge and biodiversity of specific functional microbial communities. Especially, Shewanella and Pseudomonas were enriched to accelerate the extracellular electron transfer, finally facilitating the degradation of phenolic compounds. Moreover, MEBR process effectively relieved passivation of Fe-C filler surface and prolonged lifespan of Fe-C filler. Accordingly, the synergetic effect between iron-carbon micro-electrolysis (ICME) and biological action played a significant role in performance of the integrated process. Therefore, the integrated MEBR was a promising practical process for enhancing CGW treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hydrothermal gasification of Cladophora glomerata macroalgae over its hydrochar as a catalyst for hydrogen-rich gas production.

PubMed

Safari, Farid; Norouzi, Omid; Tavasoli, Ahmad

2016-12-01

A tubular batch micro-reactor system was used for hydrothermal gasification (HTG) of Cladophora glomerata (C. glomerata) as green macroalgae found in the southern coast of the Caspian Sea, Iran. Non-catalytic tests were performed to determine the optimum condition for hydrogen production. Hydrochar, as a solid residue of non-catalytic HTG was characterized by BET, FESEM, and ICP-OES methods to determine its physiochemical properties. Surface area and pore volume of C. glomerata increased drastically after HTG. Also, the aqueous products were identified and quantified by GC-MS and GC-FID methods. Hydrochar was loaded to the reactor to determine its catalytic effect on HTG. HTG was promoted by inorganic compounds in the hydrochar and its porosity. The maximum hydrogen yield of 9.63mmol/g was observed in the presence of algal hydrochar with the weight ratio of 0.4 to feedstock. Also, acids production was inhibited while phenol production was promoted in the presence of hydrochar. Copyright © 2016 Elsevier Ltd. All rights reserved.

Novel approaches for alleviation of electrical hazards of graphite-fiber composites. [aircraft safety

NASA Technical Reports Server (NTRS)

Ramohalli, K.

1979-01-01

Four basically different approaches were considered: gasification of fibers, retention in the matrix, clumping to prevent entrainment, and electrical insulation of fibers. The techniques used to achieve them are described in some detail. These involved surface treatment of fibers to improve the wettability of fibers and coating the fibers with the selected substances before laying them up for composite fabrication. Thermogravimetric analyses were performed on the plain and treated fibers in inert (nitrogen, argon) and reactive (air) atmospheres. The treated fibers embedded in epoxy were ignited in a Bunsen flame to determine the efficiency of these treatments. A simple apparatus was assembled to detect the time for the first short circuit (in a typical electrical circuit) when exposed to the combustion products from a graphite fiber composite fire. The state-of-the-art and treated fibers cast in typical epoxy were burned and ranked for potential success. It was inferred that the gasification schemes appear promising when reduction or oxidation is tried. It was also found that some very promising candidates were available for the clumping and for the electrical insulation of fibers.

Thermal valorization of post-consumer film waste in a bubbling bed gasifier.

PubMed

Martínez-Lera, S; Torrico, J; Pallarés, J; Gil, A

2013-07-01

The use of plastic bags and film packaging is very frequent in manifold sectors and film waste is usually present in different sources of municipal and industrial wastes. A significant part of it is not suitable for mechanical recycling but could be safely transformed into a valuable gas by means of thermal valorization. In this research, the gasification of film wastes has been experimentally investigated through experiments in a fluidized bed reactor of two reference polymers, polyethylene and polypropylene, and actual post-consumer film waste. After a complete experimental characterization of the three materials, several gasification experiments have been performed to analyze the influence of the fuel and of equivalence ratio on gas production and composition, on tar generation and on efficiency. The experiments prove that film waste and analogue polymer derived wastes can be successfully gasified in a fluidized bed reactor, yielding a gas with a higher heating value in a range from 3.6 to 5.6 MJ/m3 and cold gas efficiencies up to 60%. Copyright © 2013 Elsevier Ltd. All rights reserved.

Coal derived fuel gases for molten carbonate fuel cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-11-01

Product streams from state-of-the-art and future coal gasification systems are characterized to guide fuel cell program planners and researchers in establishing performance goals and developing materials for molten carbonate fuel cells that will be compatible with gasifier product gases. Results are presented on: (1) the range of gasifier raw-gas compositions available from the major classes of coal gasifiers; (2) the degree of gas clean-up achievable with state-of-the-art and future gas clean-up systems; and (3) the energy penalties associated with gas clean-up. The study encompasses fixed-bed, fluid-bed, entrained-bed, and molten salt gasifiers operating with Eastern bituminous and Western subbituminous coals. Gasifiersmore » operating with air and oxygen blowing are evaluated, and the coal gasification product streams are characterized with respect to: (1) major gas stream constituents, e.g., CO, H/sub 2/, CO/sub 2/, CH/sub 4/, N/sub 2/, H/sub 2/O; (2) major gas stream contaminants, e.g., H/sub 2/S, COS, particulates, tars, etc.; and (3) trace element contaminants, e.g., Na, K, V, Cl, Hg, etc.« less

Energy implications of the thermal recovery of biodegradable municipal waste materials in the United Kingdom.

PubMed

Burnley, Stephen; Phillips, Rhiannon; Coleman, Terry; Rampling, Terence

2011-01-01

Waste management policies and legislation in many developed countries call for a reduction in the quantity of biodegradable waste landfilled. Anaerobic digestion, combustion and gasification are options for managing biodegradable waste while generating renewable energy. However, very little research has been carried to establish the overall energy balance of the collection, preparation and energy recovery processes for different types of wastes. Without this information, it is impossible to determine the optimum method for managing a particular waste to recover renewable energy. In this study, energy balances were carried out for the thermal processing of food waste, garden waste, wood, waste paper and the non-recyclable fraction of municipal waste. For all of these wastes, combustion in dedicated facilities or incineration with the municipal waste stream was the most energy-advantageous option. However, we identified a lack of reliable information on the energy consumed in collecting individual wastes and preparing the wastes for thermal processing. There was also little reliable information on the performance and efficiency of anaerobic digestion and gasification facilities for waste. Copyright © 2011 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chu, C.I.C.; Gillespie, B.L.

One of the most perplexing problems facing the coal industry is how to properly dispose of the waste and/or even recovery a small fraction of the Btu value of the waste, while minimizing the environmental concerns. UCC Research considers this monumental environmental problems as an opportunity to recovery useable organic materials and reduce the environmental problems created by coal waste. Mild gasification is the method used by UCC Research to realize these objectives. Coal feedstocks are fed into the mild gasification system yielding liquids, char, and gases for commercial application. The program consists of seven tasks: Task 1, Characterize Managementmore » of Coal Preparation Wastes; Task 2, Review Design Specifications and Prepare Preliminary Test Plan; Task 3, Select and Characterize Test Feedstocks; Task 4, Acquire/Construct Process Elements; Task 5, Prepare Final Test Plan; Task 6, Implement Final Test Plan; Task 7, Analyze Test Results and Assess System Economics. A schedule of the program is given. The program was initiated on September 30, 1984. Tasks 1, 2, 3, 4, 5, and 6 have been completed. Work is continuing on Task 7.« less

On-site GC/MS analysis of Chapman gasification separator liquor. Final report Jul 80-Mar 81

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thielen, C.J.; Magee, R.A.; Collins, R.V.

1981-08-01

The report gives results of a characterization of a wastewater stream from a coal gasification plant, using on-site extraction and GC/MS analysis. Extractable material in the wastewater was primarily phenols and alkylphenols, accounting for about 99% of the total mass identified. Several polynuclear aromatic compounds were also identified. The composition of the sample deteriorated even though the water was held in amber bottles at 4C: this was most evident in the concentration of dimethylphenols which dropped about 75% during 2 weeks of refrigerated storage. Ambient sample storage produced a greater decrease in the concentration of phenol, but did not appearmore » to affect the alkylphenols or the base/neutral compounds as much. The observed changes in composition should hamper any off-site wastewater treatbility studies with waters of this type. Diisopropyl ether (DIPE) extraction confirmed the 99-plus % removal efficiency of phenol which had been demonstrated in previous studies. Wet oxidation removed organics almost as efficiently as DIPE extraction, but may have limited use because of its high operating cost.« less

Investigation of flow behaviour of coal particles in a pilot-scale fluidized bed gasifier (FBG) using radiotracer technique.

PubMed

Pant, H J; Sharma, V K; Kamudu, M Vidya; Prakash, S G; Krishanamoorthy, S; Anandam, G; Rao, P Seshubabu; Ramani, N V S; Singh, Gursharan; Sonde, R R

2009-09-01

Knowledge of residence time distribution (RTD), mean residence time (MRT) and degree of axial mixing of solid phase is required for efficient operation of coal gasification process. Radiotracer technique was used to measure the RTD of coal particles in a pilot-scale fluidized bed gasifier (FBG). Two different radiotracers i.e. lanthanum-140 and gold-198 labeled coal particles (100 gm) were independently used as radiotracers. The radiotracer was instantaneously injected into the coal feed line and monitored at the ash extraction line at the bottom and gas outlet at the top of the gasifier using collimated scintillation detectors. The measured RTD data were treated and MRTs of coal/ash particles were determined. The treated data were simulated using tanks-in-series model. The simulation of RTD data indicated good degree of mixing with small fraction of the feed material bypassing/short-circuiting from the bottom of the gasifier. The results of the investigation were found useful for optimizing the design and operation of the FBG, and scale-up of the gasification process.

77 FR 36996 - South Mississippi Electric Cooperative: Plant Ratcliff, Kemper County Integrated Gasification...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-20

... DEPARTMENT OF AGRICULTURE Rural Utilities Service South Mississippi Electric Cooperative: Plant Ratcliff, Kemper County Integrated Gasification Combined-Cycle (IGCC) Project AGENCY: Rural Utilities... Combined-Cycle (IGCC) Project currently under construction in Kemper County, Mississippi (hereinafter ``the...

Production of Hydrogen from Underground Coal Gasification

DOEpatents

Upadhye, Ravindra S.

2008-10-07

A system of obtaining hydrogen from a coal seam by providing a production well that extends into the coal seam; positioning a conduit in the production well leaving an annulus between the conduit and the coal gasification production well, the conduit having a wall; closing the annulus at the lower end to seal it from the coal gasification cavity and the syngas; providing at least a portion of the wall with a bifunctional membrane that serves the dual purpose of providing a catalyzing reaction and selectively allowing hydrogen to pass through the wall and into the annulus; and producing the hydrogen through the annulus.

A techno-economic approach to plasma gasification

NASA Astrophysics Data System (ADS)

Ramos, Ana; Rouboa, Abel

2018-05-01

Within the most used Waste-to-Energy technologies plasma gasification is recent and therefore not yet widely commercialized. Thus, it is necessary to conduct a viability study to support the thorough understanding and implementation of this thermal treatment. This paper aims to assess some technical, environmental and economic aspects of plasma gasification paving the way for a more sustained waste management system, as well as taking advantage of the commodity assets granted by the technique. Therefore, results from previously published studies were updated and highlighted as a preliminary starting point in order to potentially evolve to a complete and systematic work.

Method for producing bio-fuel that integrates heat from carbon-carbon bond-forming reactions to drive biomass gasification reactions

DOEpatents

Cortright, Randy D [Madison, WI; Dumesic, James A [Verona, WI

2012-04-10

A low-temperature catalytic process for converting biomass (preferably glycerol recovered from the fabrication of bio-diesel) to synthesis gas (i.e., H.sub.2/CO gas mixture) in an endothermic gasification reaction is described. The synthesis gas is used in exothermic carbon-carbon bond-forming reactions, such as Fischer-Tropsch, methanol, or dimethylether syntheses. The heat from the exothermic carbon-carbon bond-forming reaction is integrated with the endothermic gasification reaction, thus providing an energy-efficient route for producing fuels and chemicals from renewable biomass resources.

Method for producing bio-fuel that integrates heat from carbon-carbon bond-forming reactions to drive biomass gasification reactions

DOEpatents

Cortright, Randy D.; Dumesic, James A.

2013-04-02

A low-temperature catalytic process for converting biomass (preferably glycerol recovered from the fabrication of bio-diesel) to synthesis gas (i.e., H.sub.2/CO gas mixture) in an endothermic gasification reaction is described. The synthesis gas is used in exothermic carbon-carbon bond-forming reactions, such as Fischer-Tropsch, methanol, or dimethylether syntheses. The heat from the exothermic carbon-carbon bond-forming reaction is integrated with the endothermic gasification reaction, thus providing an energy-efficient route for producing fuels and chemicals from renewable biomass resources.

Method for producing bio-fuel that integrates heat from carbon-carbon bond-forming reactions to drive biomass gasification reactions

DOEpatents

Cortright, Randy D [Madison, WI; Dumesic, James A [Verona, WI

2011-01-18

A low-temperature catalytic process for converting biomass (preferably glycerol recovered from the fabrication of bio-diesel) to synthesis gas (i.e., H.sub.2/CO gas mixture) in an endothermic gasification reaction is described. The synthesis gas is used in exothermic carbon-carbon bond-forming reactions, such as Fischer-Tropsch, methanol, or dimethylether syntheses. The heat from the exothermic carbon-carbon bond-forming reaction is integrated with the endothermic gasification reaction, thus providing an energy-efficient route for producing fuels and chemicals from renewable biomass resources.

Experimental and modeling study of high performance direct carbon solid oxide fuel cell with in situ catalytic steam-carbon gasification reaction

NASA Astrophysics Data System (ADS)

Xu, Haoran; Chen, Bin; Zhang, Houcheng; Tan, Peng; Yang, Guangming; Irvine, John T. S.; Ni, Meng

2018-04-01

In this paper, 2D models for direct carbon solid oxide fuel cells (DC-SOFCs) with in situ catalytic steam-carbon gasification reaction are developed. The simulation results are found to be in good agreement with experimental data. The performance of DC-SOFCs with and without catalyst are compared at different operating potential, anode inlet gas flow rate and operating temperature. It is found that adding suitable catalyst can significantly speed up the in situ steam-carbon gasification reaction and improve the performance of DC-SOFC with H2O as gasification agent. The potential of syngas and electricity co-generation from the fuel cell is also evaluated, where the composition of H2 and CO in syngas can be adjusted by controlling the anode inlet gas flow rate. In addition, the performance DC-SOFCs and the percentage of fuel in the outlet gas are both increased with increasing operating temperature. At a reduced temperature (below 800 °C), good performance of DC-SOFC can still be obtained with in-situ catalytic carbon gasification by steam. The results of this study form a solid foundation to understand the important effect of catalyst and related operating conditions on H2O-assisted DC-SOFCs.

Application of a Cloud Model-Set Pair Analysis in Hazard Assessment for Biomass Gasification Stations.

PubMed

Yan, Fang; Xu, Kaili

2017-01-01

Because a biomass gasification station includes various hazard factors, hazard assessment is needed and significant. In this article, the cloud model (CM) is employed to improve set pair analysis (SPA), and a novel hazard assessment method for a biomass gasification station is proposed based on the cloud model-set pair analysis (CM-SPA). In this method, cloud weight is proposed to be the weight of index. In contrast to the index weight of other methods, cloud weight is shown by cloud descriptors; hence, the randomness and fuzziness of cloud weight will make it effective to reflect the linguistic variables of experts. Then, the cloud connection degree (CCD) is proposed to replace the connection degree (CD); the calculation algorithm of CCD is also worked out. By utilizing the CCD, the hazard assessment results are shown by some normal clouds, and the normal clouds are reflected by cloud descriptors; meanwhile, the hazard grade is confirmed by analyzing the cloud descriptors. After that, two biomass gasification stations undergo hazard assessment via CM-SPA and AHP based SPA, respectively. The comparison of assessment results illustrates that the CM-SPA is suitable and effective for the hazard assessment of a biomass gasification station and that CM-SPA will make the assessment results more reasonable and scientific.

Two stage fluid bed-plasma gasification process for solid waste valorisation: Technical review and preliminary thermodynamic modelling of sulphur emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morrin, Shane, E-mail: shane.morrin@ucl.ac.uk; Advanced Plasma Power, South Marston Business park, Swindon, SN3 4DE; Lettieri, Paola, E-mail: p.lettieri@ucl.ac.uk

2012-04-15

Highlights: Black-Right-Pointing-Pointer We investigate sulphur during MSW gasification within a fluid bed-plasma process. Black-Right-Pointing-Pointer We review the literature on the feed, sulphur and process principles therein. Black-Right-Pointing-Pointer The need for research in this area was identified. Black-Right-Pointing-Pointer We perform thermodynamic modelling of the fluid bed stage. Black-Right-Pointing-Pointer Initial findings indicate the prominence of solid phase sulphur. - Abstract: Gasification of solid waste for energy has significant potential given an abundant feed supply and strong policy drivers. Nonetheless, significant ambiguities in the knowledge base are apparent. Consequently this study investigates sulphur mechanisms within a novel two stage fluid bed-plasma gasification process.more » This paper includes a detailed review of gasification and plasma fundamentals in relation to the specific process, along with insight on MSW based feedstock properties and sulphur pollutant therein. As a first step to understanding sulphur partitioning and speciation within the process, thermodynamic modelling of the fluid bed stage has been performed. Preliminary findings, supported by plant experience, indicate the prominence of solid phase sulphur species (as opposed to H{sub 2}S) - Na and K based species in particular. Work is underway to further investigate and validate this.« less

Polycyclic aromatic hydrocarbon formation during the gasification of sewage sludge in sub- and supercritical water: Effect of reaction parameters and reaction pathways.

PubMed

Gong, Miao; Wang, Yulan; Fan, Yujie; Zhu, Wei; Zhang, Huiwen; Su, Ying

2018-02-01

The formation of polycyclic aromatic hydrocarbon is a widespread issue during the supercritical water gasification of sewage sludge, which directly reduces the gasification efficiency and restricts the technology practical application. The changes of the concentrations and forms as well as the synthesis rate of polycyclic aromatic hydrocarbons in the residues from supercritical water gasification of dewatered sewage sludge were investigated to understand influence factors and the reaction pathways. Results showed that the increase of reaction temperature during the heating period favours directly concentration of polycyclic aromatic hydrocarbon (especially higher-molecular-weight), especially when it raise above 300 °C. Lower heating and cooling rate essentially extend the total reaction time. Higher polycyclic aromatic hydrocarbon concentration and higher number of rings were generally promoted by lower heating and cooling rate, longer reaction time and higher reaction temperature. The lower-molecular-weight polycyclic aromatic hydrocarbons can be directly generated through the decomposition of aromatic-containing compounds in sewage sludge, as well as 3-ring and 4-ring polycyclic aromatic hydrocarbons can be formed by aromatization of steroids. Possible mechanisms of reaction pathways of supercritical water gasification of sewage sludge were also proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Application of a Cloud Model-Set Pair Analysis in Hazard Assessment for Biomass Gasification Stations

PubMed Central

Yan, Fang; Xu, Kaili

2017-01-01

Because a biomass gasification station includes various hazard factors, hazard assessment is needed and significant. In this article, the cloud model (CM) is employed to improve set pair analysis (SPA), and a novel hazard assessment method for a biomass gasification station is proposed based on the cloud model-set pair analysis (CM-SPA). In this method, cloud weight is proposed to be the weight of index. In contrast to the index weight of other methods, cloud weight is shown by cloud descriptors; hence, the randomness and fuzziness of cloud weight will make it effective to reflect the linguistic variables of experts. Then, the cloud connection degree (CCD) is proposed to replace the connection degree (CD); the calculation algorithm of CCD is also worked out. By utilizing the CCD, the hazard assessment results are shown by some normal clouds, and the normal clouds are reflected by cloud descriptors; meanwhile, the hazard grade is confirmed by analyzing the cloud descriptors. After that, two biomass gasification stations undergo hazard assessment via CM-SPA and AHP based SPA, respectively. The comparison of assessment results illustrates that the CM-SPA is suitable and effective for the hazard assessment of a biomass gasification station and that CM-SPA will make the assessment results more reasonable and scientific. PMID:28076440

Microwave induced plasma for solid fuels and waste processing: A review on affecting factors and performance criteria.

PubMed

Ho, Guan Sem; Faizal, Hasan Mohd; Ani, Farid Nasir

2017-11-01

High temperature thermal plasma has a major drawback which consumes high energy. Therefore, non-thermal plasma which uses comparatively lower energy, for instance, microwave plasma is more attractive to be applied in gasification process. Microwave-induced plasma gasification also carries the advantages in terms of simplicity, compactness, lightweight, uniform heating and the ability to operate under atmospheric pressure that gains attention from researchers. The present paper synthesizes the current knowledge available for microwave plasma gasification on solid fuels and waste, specifically on affecting parameters and their performance. The review starts with a brief outline on microwave plasma setup in general, and followed by the effect of various operating parameters on resulting output. Operating parameters including fuel characteristics, fuel injection position, microwave power, addition of steam, oxygen/fuel ratio and plasma working gas flow rate are discussed along with several performance criteria such as resulting syngas composition, efficiency, carbon conversion, and hydrogen production rate. Based on the present review, fuel retention time is found to be the key parameter that influences the gasification performance. Therefore, emphasis on retention time is necessary in order to improve the performance of microwave plasma gasification of solid fuels and wastes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Successful implementation of biochar carbon sequestration in European soils requires additional benefits and close collaboration with the bioenergy sector

NASA Astrophysics Data System (ADS)

Hauggaard-Nielsen, Henrik; Müller-Stöver, Dorette; Bruun, Esben W.; Petersen, Carsten T.

2014-05-01

Biochar soil application has been proposed as a measure to mitigate climate change and on the same time improve soil fertility by increased soil carbon sequestration. However, while on tropical soils the beneficial effects of biochar application on crop growth often become immediately apparent, it has been shown to be more difficult to demonstrate these effects on the more fertile soils in temperate regions. Therefore and because of the lack of carbon credits for farmers, it is necessary to link biochar application to additional benefits, both related to agricultural as well as to bioenergy production. Thermal gasification of biomass is an efficient (95% energy efficiency) and flexible way (able to cope with many different and otherwise difficult-to-handle biomass fuels) to generate bioenergy, while producing a valuable by-product - gasification biochar, containing recalcitrant carbon and essential crop nutrients. The use of the residual char product in agricultural soils will add value to the technology as well as result in additional soil benefits such as providing plant nutrients and improving soil water-holding capacity while reducing leaching risks. From a soil column (30 x 130 cm) experiment with gasification straw biochar amendment to coarse sandy subsoil increased root density of barley at critical depths in the soil profile reducing the mechanical resistance was shown, increasing yields, and the soil's capacity to store plant available water. Incorporation of residuals from a bioenergy technology like gasification show great potentials to reduce subsoil constraints increasing yield potentials on poor soils. Another advantage currently not appropriately utilized is recovery of phosphorus (P). In a recent pot experiments char products originating from low-temperature gasification of various biofuels were evaluated for their suitability as P fertilizers. Wheat straw gasification biochar generally had a low P content but a high P plant availability. To improve the fertilizer value while keeping a high carbon content in the char, the gasification of a combination of sewage sludge and wheat straw was implemented, resulting in a char product with a promising performance as a fertilizer and soil amendment. To implement gasification-biochar as a promising soil improver on the marked, independently of potential carbon market developments and CO2 certificates, stakeholder involvement is strongly required. In a newly established project consortium Bregentved Estate (one of Europe's largest agriculture companies) and the DONG Energy company (one of the leading energy groups in Northern Europe) are in a joint effort trying to integrate the economic matrix of i) biomass needed for bioenergy, ii) profit from energy generation and iii) soil advantages gained from biochar application. Experiments are conducted with a 6MW biomass gasification demonstration plant producing straw biochar used in field plots (12 m x 250 m).

Development of ITM Oxygen Technology for Low-cost and Low-emission Gasification and Other Industrial Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fogash, Kevin

2015-12-15

Air Products carried out a scope of work under DOE Award No. DE-FE0012065 “Development of ITM Oxygen Technology for Low-cost and Low-emission Gasification and Other Industrial Applications” with subcontractors Ceramatec, Penn State, and WorleyParsons. The scope of work under this award was aimed at furthering the development of the Ion Transport Membrane (ITM) Oxygen production process toward a demonstration-scale facility known as the Oxygen Development Facility (ODF). Specific activities will help to enable design and construction of the ODF through advancement of a number of challenging technical elements that are required to manage risk in the initial deployment of ITMmore » technology. Major objectives of the work included developing ITM Oxygen ceramic membrane materials with improved performance and reliability, optimizing ceramic module geometry and fabrication methods, testing module performance, trialing the improved fabrication process at commercial scale in the Ceramic Membrane Module Fabrication Facility (CerFab), and advancing engineering development of the ITM oxygen production process, including vessel design and contaminant control measures to prepare for deployment of the ODF. The comprehensive report that follows details the team’s work, which includes several notable accomplishments: 1) compressive creep, a likely limiter of ceramic module lifetime in service, was demonstrated to be retarded by an order of magnitude by changes in material formulation, module joining dimensions, and internal wafer geometry; 2) two promising new materials were shown to be superior to the incumbent ITM material in a key material parameter related to oxygen flux; 3) module degradation mechanisms were identified following operation in large pilot-scale equipment; 4) options for utilizing ITM in a coal-to-liquids (CTL) facility to enable liquids production with carbon capture were identified and studied; and 5) the benefits of potential improvements to the technology were assessed for their cost impact on ITM Oxygen applications to clean power, fuels, and other applications.« less

Development of ITM Oxygen Technology for Low-cost and Low-emission Gasification and Other Industrial Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fogash, Kevin

Air Products carried out a scope of work under DOE Award No. DE-FE0012065 “Development of ITM Oxygen Technology for Low-cost and Low-emission Gasification and Other Industrial Applications” with subcontractors Ceramatec, Penn State, and WorleyParsons. The scope of work under this award was aimed at furthering the development of the Ion Transport Membrane (ITM) Oxygen production process toward a demonstration-scale facility known as the Oxygen Development Facility (ODF). Specific activities will help to enable design and construction of the ODF through advancement of a number of challenging technical elements that are required to manage risk in the initial deployment of ITMmore » technology. Major objectives of the work included developing ITM Oxygen ceramic membrane materials with improved performance and reliability, optimizing ceramic module geometry and fabrication methods, testing module performance, trialing the improved fabrication process at commercial scale in the Ceramic Membrane Module Fabrication Facility (CerFab), and advancing engineering development of the ITM oxygen production process, including vessel design and contaminant control measures to prepare for deployment of the ODF. The comprehensive report that follows details the team’s work, which includes several notable accomplishments: 1) compressive creep, a likely limiter of ceramic module lifetime in service, was demonstrated to be retarded by an order of magnitude by changes in material formulation, module joining dimensions, and internal wafer geometry; 2) two promising new materials were shown to be superior to the incumbent ITM material in a key material parameter related to oxygen flux; 3) module degradation mechanisms were identified following operation in large pilot-scale equipment; 4) options for utilizing ITM in a coal-to-liquids (CTL) facility to enable liquids production with carbon capture were identified and studied; and 5) the benefits of potential improvements to the technology were assessed for their cost impact on ITM Oxygen applications to clean power, fuels, and other applications.« less

Influence of Biochar on C and N Transformation in Soil and Their Impact on Greenhouse Gas Emissions

NASA Astrophysics Data System (ADS)

Chintala, R.; Schumacher, T. E.; Kumar, S.; Clay, D. E.; Malo, D. D.

2014-12-01

The capacity of pyrogenic biochar to mitigate soil surface exchange of greenhouse gases (GHG) is dependent on the influence of biochar on physiochemical transformations of C and N in soils. Incorporated biochar amendments are hypothesized to interfere with transformations of C and N as a result of the unique recalcitrant chemical structure and surface complexity of biochars. The nature of interference by biochar with C and N transformations are assumed to be dynamic not only due to their highly variable amphilicity inherited from feedstock source and controlled pyrolytic processing parameters but also to variation in soil factors. Experiments comprised of laboratory and field studies were designed to gain insight into the priming effect of incorporated non-native biochar materials on the transformations of C and N species in the soil. Molecular structure and surface functionality of plant based biochar materials produced from carbon optimized gasification of corn stover (Zea mays L.), Ponderosa pine (Pinus ponderosa Lawson and C. Lawson) wood residue, and switchgrass (Panicum virgatum L.) were studied in the laboratory using NMR and SEM-EdX. Biochar materials were found to be highly hydrophobic (low H/C values) with high aromaticity. The surface morphology of all the biochar materials was highly heterogeneous and pore size ranged from 1-22µm with the faces and edges of ordered sheets. In the field study, all the three biochar types were applied at a 1% (w/w) rate to a Maddock soil (Sandy, Mixed, Frigid Entic Hapludolls) located in an eroded upper landscape position and a Brookings soil (Fine-Silty, Mixed, Superactive, Frigid Pachic Hapludolls) located in a depositional landscape position. The crop rotation is a corn (Zea mays L.) followed by soybean (Glycine max L.). The priming effect of biochars on the transformations of C and N is determined by measuring the changes in soil C (total organic carbon, microbial biomass C, hydrolyzable C, and δ 13C) and N pools (microbial biomass N, inorganic N, and δ 15N). Greenhouse gas fluxes (CO2, CH4, and N2O) were measured and correlation studies will be conducted to determine the relationship with the interference effect of biochars on C and N transformation in soil. Initial data shows that biochar has an impact especially on CO2, and N2O emissions.

Techno Economic Analysis of Hydrogen Production by gasification of biomass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Francis Lau

Biomass represents a large potential feedstock resource for environmentally clean processes that produce power or chemicals. It lends itself to both biological and thermal conversion processes and both options are currently being explored. Hydrogen can be produced in a variety of ways. The majority of the hydrogen produced in this country is produced through natural gas reforming and is used as chemical feedstock in refinery operations. In this report we will examine the production of hydrogen by gasification of biomass. Biomass is defined as organic matter that is available on a renewable basis through natural processes or as a by-productmore » of processes that use renewable resources. The majority of biomass is used in combustion processes, in mills that use the renewable resources, to produce electricity for end-use product generation. This report will explore the use of hydrogen as a fuel derived from gasification of three candidate biomass feedstocks: bagasse, switchgrass, and a nutshell mix that consists of 40% almond nutshell, 40% almond prunings, and 20% walnut shell. In this report, an assessment of the technical and economic potential of producing hydrogen from biomass gasification is analyzed. The resource base was assessed to determine a process scale from feedstock costs and availability. Solids handling systems were researched. A GTI proprietary gasifier model was used in combination with a Hysys(reg. sign) design and simulation program to determine the amount of hydrogen that can be produced from each candidate biomass feed. Cost estimations were developed and government programs and incentives were analyzed. Finally, the barriers to the production and commercialization of hydrogen from biomass were determined. The end-use of the hydrogen produced from this system is small PEM fuel cells for automobiles. Pyrolysis of biomass was also considered. Pyrolysis is a reaction in which biomass or coal is partially vaporized by heating. Gasification is a more general term, and includes heating as well as the injection of other ''ingredients'' such as oxygen and water. Pyrolysis alone is a useful first step in creating vapors from coal or biomass that can then be processed in subsequent steps to make liquid fuels. Such products are not the objective of this project. Therefore pyrolysis was not included in the process design or in the economic analysis. High-pressure, fluidized bed gasification is best known to GTI through 30 years of experience. Entrained flow, in contrast to fluidized bed, is a gasification technology applied at much larger unit sizes than employed here. Coal gasification and residual oil gasifiers in refineries are the places where such designs have found application, at sizes on the order of 5 to 10 times larger than what has been determined for this study. Atmospheric pressure gasification is also not discussed. Atmospheric gasification has been the choice of all power system pilot plants built for biomass to date, except for the Varnamo plant in Sweden, which used the Ahlstrom (now Foster Wheeler) pressurized gasifier. However, for fuel production, the disadvantage of the large volumetric flows at low pressure leads to the pressurized gasifier being more economical.« less

DEMONSTRATION BULLETIN: TEXACO GASIFICATION PROCESS TEXACO, INC.

EPA Science Inventory

The Texaco Gasification Process (TGP) has operated commercially for nearly 45 years on feeds such as natural gas, liquid petroleum fractions, coal, and petroleum coke. More than 45 plants are either operational or under development in the United States and abroad. Texaco has dev...

Optimization Review, Fairfield Coal Gasification Plant Superfund Site, Fairfield, Iowa

EPA Pesticide Factsheets

The Fairfield Coal Gasification Plant (FCGP) also known as the Fairfield Former Manufactured Gas Plant (MGP) is located in the southwest 1/4 of the southeast 1/4, Section 26, Township 72 North, Range 10 West of Jefferson County, Iowa.

Oil shale derived pollutant control materials and methods and apparatuses for producing and utilizing the same

DOEpatents

Boardman, Richard D.; Carrington, Robert A.

2010-05-04

Pollution control substances may be formed from the combustion of oil shale, which may produce a kerogen-based pyrolysis gas and shale sorbent, each of which may be used to reduce, absorb, or adsorb pollutants in pollution producing combustion processes, pyrolysis processes, or other reaction processes. Pyrolysis gases produced during the combustion or gasification of oil shale may also be used as a combustion gas or may be processed or otherwise refined to produce synthetic gases and fuels.

Process of producing liquid hydrocarbon fuels from biomass

DOEpatents

Kuester, James L.

1987-07-07

A continuous thermochemical indirect liquefaction process to convert various biomass materials into diesel-type transportation fuels which fuels are compatible with current engine designs and distribution systems comprising feeding said biomass into a circulating solid fluidized bed gasification system to produce a synthesis gas containing olefins, hydrogen and carbon monoxide and thereafter introducing the synthesis gas into a catalytic liquefaction system to convert the synthesis gas into liquid hydrocarbon fuel consisting essentially of C.sub.7 -C.sub.17 paraffinic hydrocarbons having cetane indices of 50+.

Evaluation of the Relative Merits of Herbaceous and Woody Crops for Use in Tunable Thermochemical Processing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Joon-Hyun; Martinalbo, Ilya

This report summarizes the work and findings of the grant work conducted from January 2009 until September 2011 under the collaboration between Ceres, Inc. and Choren USA, LLC. This DOE-funded project involves a head-to-head comparison of two types of dedicated energy crops in the context of a commercial gasification conversion process. The main goal of the project was to gain a better understanding of the differences in feedstock composition between herbaceous and woody species, and how these differences may impact a commercial gasification process. In this work, switchgrass was employed as a model herbaceous energy crop, and willow as amore » model short-rotation woody crop. Both crops are species native to the U.S. with significant potential to contribute to U.S. goals for renewable liquid fuel production, as outlined in the DOE Billion Ton Update (http://www1.eere.energy.gov/biomass/billion_ton_update.html, 2011). In some areas of the U.S., switching between woody and herbaceous feedstocks or blending of the two may be necessary to keep a large-scale gasifier operating near capacity year round. Based on laboratory tests and process simulations it has been successfully shown that suitable high yielding switchgrass and willow varieties exist that meet the feedstock specifications for large scale entrained flow biomass gasification. This data provides the foundation for better understanding how to use both materials in thermochemical processes. It has been shown that both switchgrass and willow varieties have comparable ranges of higher heating value, BTU content and indistinguishable hydrogen/carbon ratios. Benefits of switchgrass, and other herbaceous feedstocks, include its low moisture content, which reduce energy inputs and costs for drying feedstock. Compared to the typical feedstock currently being used in the Carbo-V® process, switchgrass has a higher ash content, combined with a lower ash melting temperature. Whether or not this may cause inefficiencies in the process, needs to be verified by long term test runs. Currently, there are not sufficient operational test data available for the Carbo-V® process for the utilization of higher ash content feedstocks. The application of currently evolving biomass pretreatment technologies, such as pelletization and torrefaction, will be able to expand the portfolio of biomass varieties and species acceptable in gasification processes. Tests showed that 6 mm diameter pellets of switchgrass were superior to 8 mm diameter pellets produced in a flat dye press, and that torrefaction of switchgrass produced an excellent (but currently costly) feedstock that could be handled, crushed, and combusted in a manner compatible with any coal-fed gasification facility. Ceres will use this information in the development of high yielding, dedicated energy crops specifically tailored for thermochemical conversion. CHOREN will make use of the information for improvement or development of low cost, highly efficient biomass gasification processes that convert a wide variety of biomass feedstocks to fuels, chemicals, heat and power via the production of tar free green syngas on an industrial scale.« less

Philadelphia gas works medium-Btu coal gasification project: environmental assessment. [GKT supplied by Krupp-Koppers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-12-01

The coal gasification plant will occupy a 43-acre site, known as the Riverside Site, located along the Delaware River next to Port Richmond between the Betsy Ross and Benjamin Franklin Bridges. The cleared site was previously used for industrial purposes and has a G-2 industrial zoning. Adverse impacts during the construction phase of the project are not expected to be significantly different than those occurring during any major industrial construction project. During operation of the coal gasification facility, specific mitigative measures have been designed into the facility to avoid adverse environmental impacts wherever possible. In addition to these extensive engineeringmore » safeguards, elaborate monitoring and control instrumentation shall be used. The GKT entrained bed, oxygen-blown gasification process provided by Krupp/Koppers was selected because it is a commercially proven system and because of its positive environmental characteristics such as its ability to gasify many coal types and the fact that it does not produce tars, phenols, or ammonia. During gasification of the coal, pollutants such as heavy metals in the coal are concentrated into the slag and ash. None of these pollutants are found in the product gas. The facility will produce 250 tpd of non-hazardous slag and fly ash. The combined slag and fly ash will occupy 347 cubic yards per day of landfill volume. Available haulers and landfills have been identified.A sophisticated health and safety program will include appropriate monitoring instruments for CO, H/sub 2/, H/sub 2/S, polynuclear aromatic hydrocarbons, organic compounds, and coal dust. Air emissions from operation of the coal gasification plant are not considered significant. Dust control systems have been designed into the facility to minimize fugitive dust emissions.« less

Operating and environmental performances of commercial-scale waste gasification and melting technology.

PubMed

Tanigaki, Nobuhiro; Fujinaga, Yasuka; Kajiyama, Hirohisa; Ishida, Yoshihiro

2013-11-01

Gasification technologies for waste processing are receiving increased interest. A lot of gasification technologies, including gasification and melting, have been developed in Japan and Europe. However, the flue gas and heavy metal behaviors have not been widely reported, even though those of grate furnaces have been reported. This article reports flue gas components of gasification and melting technology in different flue gas treatment systems. Hydrogen chloride concentrations at the inlet of the bag filter ranged between 171 and 180 mg Nm(-3) owing to de-acidification by limestone injection to the gasifier. More than 97.8% of hydrogen chlorides were removed by a bag filter in both of the flue gas treatment systems investigated. Sulfur dioxide concentrations at the inlet of the baghouse were 4.8 mg Nm(-3) and 12.7 mg Nm(-3), respectively. Nitrogen oxides are highly decomposed by a selective catalytic reduction system. Owing to the low regenerations of polychlorinated dibenzo-p-dioxins and furans, and the selective catalytic reduction system, the concentrations of polychlorinated dibenzo-p-dioxins and furans at the stacks were significantly lower without activated carbon injection. More than 99% of chlorine is distributed in fly ash. Low-boiling-point heavy metals, such as lead and zinc, are distributed in fly ash at rates of 97.6% and 96.5%, respectively. Most high-boiling-point heavy metals, such as iron and copper, are distributed in metal. It is also clarified that the slag is stable and contains few harmful heavy metals, such as lead. The heavy metal distribution behaviors are almost the same regardless of the compositions of the processed waste. These results indicate that the gasification of municipal solid waste constitutes an ideal approach to environmental conservation and resource recycling.

Systems Based Approaches for Thermochemical Conversion of Biomass to Bioenergy and Bioproducts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, Steven

2016-07-11

Auburn’s Center for Bioenergy and Bioproducts conducts research on production of synthesis gas for use in power generation and the production of liquid fuels. The overall goal of our gasification research is to identify optimal processes for producing clean syngas to use in production of fuels and chemicals from underutilized agricultural and forest biomass feedstocks. This project focused on construction and commissioning of a bubbling-bed fluidized-bed gasifier and subsequent shakedown of the gasification and gas cleanup system. The result of this project is a fully commissioned gasification laboratory that is conducting testing on agricultural and forest biomass. Initial tests onmore » forest biomass have served as the foundation for follow-up studies on gasification under a more extensive range of temperatures, pressures, and oxidant conditions. The laboratory gasification system consists of a biomass storage tank capable of holding up to 6 tons of biomass; a biomass feeding system, with loss-in-weight metering system, capable of feeding biomass at pressures up to 650 psig; a bubbling-bed fluidized-bed gasification reactor capable of operating at pressures up to 650 psig and temperatures of 1500oF with biomass flowrates of 80 lb/hr and syngas production rates of 37 scfm; a warm-gas filtration system; fixed bed reactors for gas conditioning; and a final quench cooling system and activated carbon filtration system for gas conditioning prior to routing to Fischer-Tropsch reactors, or storage, or venting. This completed laboratory enables research to help develop economically feasible technologies for production of biomass-derived synthesis gases that will be used for clean, renewable power generation and for production of liquid transportation fuels. Moreover, this research program provides the infrastructure to educate the next generation of engineers and scientists needed to implement these technologies.« less

BIMOMASS GASIFICATION PILOT PLANT STUDY

EPA Science Inventory

The report gives results of a gasification pilot program using two biomass feedstocks: bagasse pellets and wood chips. he object of the program was to determine the properties of biomass product gas and its suitability as a fuel for gas-turbine-based power generation cycles. he f...

TECHNOECONOMIC APPRAISAL OF INTEGRATED GASIFICATION COMBINED-CYCLE POWER GENERATION

EPA Science Inventory

The report is a technoeconomic appraisal of the integrated (coal) gasification combined-cycle (IGCC) system. lthough not yet a proven commercial technology, IGCC is a future competitive technology to current pulverized-coal boilers equipped with SO2 and NOx controls, because of i...

BIOMASS GASIFICATION FOR AGRICULTURAL ENERGY SOURCES AND SOIL ENRICHMENT

EPA Science Inventory

Phase I of the Biomass Gasification Project gave birth to many success stories and demonstrated enormous potential for members of the local agricultural community and for students within the university.

Community-building

Watauga County Cooperative Ext...

78 FR 43870 - Hydrogen Energy California's Integrated Gasification Combined Cycle Project; Preliminary Staff...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-22

... Combined Cycle Project; Preliminary Staff Assessment and Draft Environmental Impact Statement AGENCY... Combined Cycle Project Preliminary Staff Assessment/Draft Environmental Impact Statement (PSA/DEIS) (DOE... Gasification Combined Cycle Project, which would be designed, constructed, and operated by HECA, LLC. HECA's...

A short review on the potential of coffee husk gasification for sustainable energy in Uganda.

PubMed

Miito, Gilbert John; Banadda, Noble

2017-01-01

Agricultural biomass is widely recognized as a clean and renewable energy source, with increasing potential to replace conventional fossil fuels in the energy market. Uganda, like other developing countries, has a high dependency (91%) on wood fuel, leading to environmental degradation. With a coffee production of 233 Metric Tonnes per annum, relating to 46.6 Mega Tonnes of coffee husks from processing, transforming these husks into syngas through gasification can contribute to resolving the existing energy challenges. The objective of this article is to briefly review the energy potential of coffee husks through gasification, and how the gasification process could increase energy recoveries for coffee farmers. Previous  findings indicate that the 46.6 Mega Tonnes per year of coffee husks generated in Uganda, with a heating value of 18.34 MJ/kg, is capable of generating 24 GWh of energy. This will address a 0.7% portion of the energy situation in Uganda, while protecting the environment.

Modeling and comparative assessment of bubbling fluidized bed gasification system for syngas production - a gateway for a cleaner future in Pakistan.

PubMed

Shehzad, Areeb; Bashir, Mohammed J K; Horttanainen, Mika; Manttari, Mika; Havukainen, Jouni; Abbas, Ghulam

2017-06-19

The present study explores the potential of MSW gasification for exergy analysis and has been recently given a premier attention in a region like Pakistan where the urbanization is rapidly growing and resources are few. The plant capacity was set at 50 MW based on reference data available and the total exergetic efficiency was recorded to be 31.5 MW. The largest irreversibility distribution appears in the gasifier followed by methanation unit and CO 2 capture. The effect of process temperature, equivalence ratio and MSW moisture content was explored for inspecting the variations in syngas composition, lower heating value, carbon conversion efficiency and cold gas efficiency. Special attention of the paper is paid to the comparative assessment of MSW gasification products in four regions, namely Pakistan, USA, UAE and Thailand. This extended study gave an insight into the spectrum of socioeconomic conditions with varying MSW compositions in order to explain the effect of MSW composition variance on the gasification products.

CO2 gasification of char from lignocellulosic garden waste: Experimental and kinetic study.

PubMed

Gupta, Ankita; Thengane, Sonal K; Mahajani, Sanjay

2018-04-25

In this study, the dry leaves litter from jackfruit, raintree, mango and eucalyptus trees, lignin, and cellulose were characterized, pyrolysed, and evaluated for their char reactivity towards CO 2 gasification using TGA. The differences in char reactivity were attributed to the difference in char morphology and the varying inorganic contents. The mineral analysis of biomass ash showed the presence of alkali minerals some of which could act as catalysts. The adverse effect of high silica content was also evident through the experimental results. The kinetic parameters for gasification reaction were determined using three different reaction models. A modified random pore model was investigated to account for the influence of inorganic content. The effect of external catalyst on CO 2 gasification was also studied by adding potassium carbonate to biomass char and pellets. The results obtained from this study can be conveniently used in the design of a gasifier for lignocellulosic garden waste. Copyright © 2018 Elsevier Ltd. All rights reserved.

A short review on the potential of coffee husk gasification for sustainable energy in Uganda

PubMed Central

Miito, Gilbert John; Banadda, Noble

2017-01-01

Agricultural biomass is widely recognized as a clean and renewable energy source, with increasing potential to replace conventional fossil fuels in the energy market. Uganda, like other developing countries, has a high dependency (91%) on wood fuel, leading to environmental degradation. With a coffee production of 233 Metric Tonnes per annum, relating to 46.6 Mega Tonnes of coffee husks from processing, transforming these husks into syngas through gasification can contribute to resolving the existing energy challenges. The objective of this article is to briefly review the energy potential of coffee husks through gasification, and how the gasification process could increase energy recoveries for coffee farmers. Previous  findings indicate that the 46.6 Mega Tonnes per year of coffee husks generated in Uganda, with a heating value of 18.34 MJ/kg, is capable of generating 24 GWh of energy. This will address a 0.7% portion of the energy situation in Uganda, while protecting the environment. PMID:29259766

Characterization of ash melting behaviour at high temperatures under conditions simulating combustible solid waste gasification.

PubMed

Niu, Miaomiao; Dong, Qing; Huang, Yaji; Jin, Baosheng; Wang, Hongyan; Gu, Haiming

2018-05-01

To achieve high-temperature gasification-melting of combustible solid waste, ash melting behaviour under conditions simulating high-temperature gasification were studied. Raw ash (RA) and gasified ash (GA) were prepared respectively by waste ashing and fluidized bed gasification. Results of microstructure and composition of the two-ash indicated that GA showed a more porous structure and higher content of alkali and alkali earth metals among metallic elements. Higher temperature promoted GA melting and could reach a complete flowing state at about 1250°C. The order of melting rate of GA under different atmospheres was reducing condition > inert condition > oxidizing condition, which might be related to different existing forms of iron during melting and different flux content with atmosphere. Compared to RA, GA showed lower melting activity at the same condition due to the existence of an unconverted carbon and hollow structure. The melting temperature for sufficient melting and separation of GA should be at least 1250°C in this work.

Enhanced Reduction of Few-Layer Graphene Oxide via Supercritical Water Gasification of Glycerol

PubMed Central

Arcelus-Arrillaga, Pedro; Millan, Marcos; Suelves, Isabel

2017-01-01

A sustainable and effective method for de-oxygenation of few-layer graphene oxide (FLGO) by glycerol gasification in supercritical water (SCW) is described. In this manner, reduction of FLGO and valorization of glycerol, in turn catalyzed by FLGO, are achieved simultaneously. The addition of glycerol enhanced FLGO oxygen removal by up to 59% due to the in situ hydrogen generation as compared to the use of SCW only. Physicochemical characterization of the reduced FLGO (rFLGO) showed a high restoration of the sp2-conjugated carbon network. FLGO sheets with a starting C/O ratio of 2.5 are reduced by SCW gasification of glycerol to rFLGO with a C/O ratio of 28.2, above those reported for hydrazine-based methods. Additionally, simultaneous glycerol gasification resulted in the concurrent production of H2, CO, CH4 and valuable hydrocarbons such as alkylated and non-alkylated long chain hydrocarbon (C12–C31), polycyclic aromatic hydrocarbons (PAH), and phthalate, phenol, cresol and furan based compounds. PMID:29240720

Reforming of glucose and wood at the critical conditions of water

NASA Technical Reports Server (NTRS)

Modell, M.

1977-01-01

Reforming of organics in aqueous solutions is being investigated as a potential waste treatment process. Earlier studies showed that glucose in water reacts to form a gaseous mixture of CO, H2, CH4, CO2, C2H6, and C2H4 in the vicinity of the critical conditions of water (374 C, 22 MPa). The earlier work has been extended to determine the effect of variations in temperature and feed concentration on the extent of gasification. The percent gasification decreases with increasing feed concentration, indicating an overall kinetic order less than unity. Surprisingly, the percent gasification decreases with increasing temperature. A number of preliminary experiments were conducted with maple sawdust feed, which was thought to be representative of complex organic wastes from paper and vegetable matter. Once again, no solid products were found under the critical conditions; the percent gasification ranged from 16 to 88 percent, depending on the feed composition and residence time.

Numerical investigation of cryogen re-gasification in a plate heat exchanger

NASA Astrophysics Data System (ADS)

Malecha, Ziemowit; Płuszka, Paweł; Brenk, Arkadiusz

2017-12-01

The efficient re-gasification of cryogen is a crucial process in many cryogenic installations. It is especially important in the case of LNG evaporators used in stationary and mobile applications (e.g. marine and land transport). Other gases, like nitrogen or argon can be obtained at highest purity after re-gasification from their liquid states. Plate heat exchangers (PHE) are characterized by a high efficiency. Application of PHE for liquid gas vaporization processes can be beneficial. PHE design and optimization can be significantly supported by numerical modelling. Such calculations are very challenging due to very high computational demands and complexity related to phase change modelling. In the present work, a simplified mathematical model of a two phase flow with phase change was introduced. To ensure fast calculations a simplified two-dimensional (2D) numerical model of a real PHE was developed. It was validated with experimental measurements and finally used for LNG re-gasification modelling. The proposed numerical model showed to be orders of magnitude faster than its full 3D original.

Hydrogen and syngas production by catalytic gasification of algal biomass (Cladophora glomerata L.) using alkali and alkaline-earth metals compounds.

PubMed

Ebadi, Abdol Ghaffar; Hisoriev, Hikmat; Zarnegar, Mohammad; Ahmadi, Hamed

2018-01-02

The steam gasification of algal biomass (Cladophora glomerata L.) in presence of alkali and alkaline-earth metal compounds catalysts was studied to enhance the yield of syngas and reduce its tar content through cracking and reforming of condensable fractions. The commercial catalysts used include NaOH, KHCO 3 , Na 3 PO 4 and MgO. The gasification runs carried out with a research scale, biomass gasification unit, show that the NaOH has a strong potential for production of hydrogen, along with the added advantages of char converting and tar destruction, allowing enhancement of produced syngas caloric value. When the temperature increased from 700°C to 900°C, the tar content in the gas sharply decreased, while the hydrogen yield increased. Increasing steam/biomass ratio significantly increased hydrogen yield and tar destruction; however, the particle size in the range of 0.5-2.5 mm played a minor role in the process.

Equilibrium model analysis of waste plastics gasification using CO2 and steam.

PubMed

Kannan, P; Lakshmanan, G; Al Shoaibi, A; Srinivasakannan, C

2017-12-01

Utilization of carbon dioxide (CO 2 ) in thermochemical treatment of waste plastics may significantly help to improve CO 2 recycling, thus simultaneously curtailing dioxins/furans and CO 2 emissions. Although CO 2 is not such an effective gasifying agent as steam, a few investigations have explored the utilization of CO 2 in conjunction with steam to achieve somewhat higher carbon conversion. This work presents a comparative evaluation study of CO 2 and steam gasification of a typical post-consumer waste plastics mixture using an Aspen Plus equilibrium model. The effect of flow rate of gasifying medium (CO 2 and/or steam) and gasification temperature on product gas composition, carbon conversion, and cold gas efficiency has been analyzed. Simulation results demonstrate that CO 2 can serve as a potential gasifying agent for waste plastics gasification. The resulting product gas was rich in CO whereas CO 2 -steam blends yield a wider H 2 /CO ratio, thus extending the applications of the product gas.

Investigation on the fates of vanadium and nickel during co-gasification of petroleum coke with biomass.

PubMed

Li, Jiazhou; Wang, Xiaoyu; Wang, Bing; Zhao, Jiantao; Fang, Yitian

2018-06-01

This study investigates the volatilization behaviors and mineral transformation of vanadium and nickel during co-gasification of petroleum coke with biomass. Moreover, the evolution of occurrence modes of vanadium and nickel was also determined by the method of sequential chemical extraction. The results show that the volatilities of vanadium and nickel in petroleum coke have a certain level of growth with an increase in the temperature. With the addition of biomass, their volatilities both show an obvious decrease. Organic matter and stable forms are the dominant chemical forms of vanadium and nickel. After gasification, organic-bound vanadium and nickel decompose completely and convert into other chemical forms. The crystalline phases of vanadium trioxide, coulsonite, nickel sulfide, and elemental nickel are clearly present in petroleum coke and biomass gasification ashes. When the addition of biomass reaches 60 wt%, the diffraction peaks of orthovanadate are found while that of vanadium trioxide disappear. Copyright © 2018 Elsevier Ltd. All rights reserved.

Interaction of nickel-based SOFC anodes with trace contaminants from coal-derived synthesis gas

NASA Astrophysics Data System (ADS)

Hackett, Gregory Allen

New and efficient methods of producing electrical energy from natural resources have become an important topic for researchers. Integrated gasification and fuel cell (IGFC) systems offer a fuel-flexible, high-efficiency method of energy generation. Specifically, in coal gasification processes, coal can be changed into a high-quality gaseous fuel suitable for feeding solid oxide fuel cells (SOFCs). However, trace species found in coal synthesis gas (syngas) may have a deleterious effect on the performance of nickel-based SOFC anodes. Generally, the cost of removing these species down to parts per million (ppm) levels is high. The purpose of this research is to determine the highest amount of contaminant that results in a low rate (˜1% per 1000 h) of cell performance degradation, allowing the SOFC to produce usable power for 40,000 hours. The cell performance degradation rate was determined for benzene, naphthalene, and mercury-doped syngas based on species concentration. Experimental data are fitted with degradation models to predict cell lifetime behavior. From these results, the minimum coal syngas cleanup required for these trace materials is determined. It is found that for a final cell voltage of 0.6 V, naphthalene and benzene must be cleaned to 360 ppm and less than 150 ppm, respectively. No additional cleaning is required for mercury beyond established environmental standards. Additionally, a detailed attack and recovery mechanism is proposed for the hydrocarbon species and their interaction with the fuel cell. This mechanism is proposed by considering the type of degradation models predicted and how carbon would interact with the Ni-YSZ anode to justify those models. The mechanism postulates that carbon is diffusing into the nickel structure, creating a metal solution. Once the nickel is saturated, the carbon begins to deposit on the nickel surface, reducing the electrode active area. The formation of metal solutions and the deposition of carbon results in reduced cell productivity.

Expansion of high-temperature; high-pressure data set for coal gasification: Sixth quarterly report, December 28, 1985-March 28, 1986

DOE Office of Scientific and Technical Information (OSTI.GOV)

Solomon, P.R.; Serio, M.A.; Hamblen, D.G.

1986-01-01

During the sixth quarter, work was completed on modifications of the high pressure reactor (HPR) system for higher pressure (600 psig) operation. A series of pyrolysis experiments was completed in the HPR using mixtures of nitrogen and oxygen at various pressures and compositions. The original intention of the O/sub 2//N/sub 2/ experiments was to examine the effects of oxygen on the pyrolysis product distribution and the char reactivity. Unfortunately, at the temperature, residence time and pressure used for most of the experiments in this series (817/sup 0/C, 0.47 s, 26 psig) nearly complete oxidation of the char and volatile productsmore » occurred. Additional CO/sub 2/ gasification experiments were done to provide a database for revising the test plan. These were done at a variety of temperatures, pressures and CO/sub 2/ concentrations. The reactor was then switched back to nitrogen and additional pyrolysis experiments were done at high pressure (300 psig). When it was observed that the material balance was falling off slightly, it was decided to repeat some of the previous pyrolysis experiments at low pressure. There appeared to be a small, but systematic, reduction in char recovery. We continued to do char reactivity and surface area measurements for chars using the new non-isothermal technique described in the Fifth Quarterly report. A comparison was made of the results for char, tar, and gas yields for 1 atm and 5 atm (60 psig) experiments in the HTR. The asymptotic yield of about 10% was similar for both sets of experiments. A comparison was also made of tar yields for the Montana Rosebud coal from experiments in the HPR and HTR. The observed tar yields were in good agreement for similar experimental conditions. A preliminary version of a particle temperature model for the HPR was completed during the past quarter. 9 refs., 2 figs., 3 tabs.« less

Liquid CO 2/Coal Slurry for Feeding Low Rank Coal to Gasifiers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marasigan, Jose; Goldstein, Harvey; Dooher, John

2013-09-30

This study investigates the practicality of using a liquid CO 2/coal slurry preparation and feed system for the E-Gas™ gasifier in an integrated gasification combined cycle (IGCC) electric power generation plant configuration. Liquid CO 2 has several property differences from water that make it attractive for the coal slurries used in coal gasification-based power plants. First, the viscosity of liquid CO 2 is much lower than water. This means it should take less energy to pump liquid CO 2 through a pipe compared to water. This also means that a higher solids concentration can be fed to the gasifier, whichmore » should decrease the heat requirement needed to vaporize the slurry. Second, the heat of vaporization of liquid CO 2 is about 80% lower than water. This means that less heat from the gasification reactions is needed to vaporize the slurry. This should result in less oxygen needed to achieve a given gasifier temperature. And third, the surface tension of liquid CO 2 is about 2 orders of magnitude lower than water, which should result in finer atomization of the liquid CO 2 slurry, faster reaction times between the oxygen and coal particles, and better carbon conversion at the same gasifier temperature. EPRI and others have recognized the potential that liquid CO 2 has in improving the performance of an IGCC plant and have previously conducted systemslevel analyses to evaluate this concept. These past studies have shown that a significant increase in IGCC performance can be achieved with liquid CO 2 over water with certain gasifiers. Although these previous analyses had produced some positive results, they were still based on various assumptions for liquid CO 2/coal slurry properties.« less

Unconventional Coal in Wyoming: IGCC and Gasification of Direct Coal Liquefaction Residue

NASA Astrophysics Data System (ADS)

Schaffers, William Clemens

Two unconventional uses for Wyoming Powder River Basin coal were investigated in this study. The first was the use of coal fired integrated gasification combined cycle (IGCC) plants to generate electricity. Twenty-eight different scenarios were modeled using AspenPlusRTM software. These included slurry, mechanical and dried fed gasifiers; Wyodak and Green River coals, 0%, 70%, and 90% CO2 capture; and conventional evaporative vs air cooling. All of the models were constructed on a feed basis of 6,900 tons of coal per day on an "as received basis". The AspenPlus RTM results were then used to create economic models using Microsoft RTM Excel for each configuration. These models assumed a 3 year construction period and a 30 year plant life. Results for capital and operating costs, yearly income, and internal rates of return (IRR) were compared. In addition, the scenarios were evaluated to compare electricity sales prices required to obtain a 12% IRR and to determine the effects of a carbon emissions tax on the sales price. The second part of the study investigated the gasification potential of residue remaining from solvent extraction or liquefaction of Powder River Basin Coal. Coal samples from the Decker mine on the Wyoming-Montana border were extracted with tetralin at a temperature of 360°C and pressure of 250 psi. Residue from the extraction was gasified with CO2 or steam at 833°C, 900°C and 975°C at pressures of 0.1 and 0.4 MPa. Product gases were analyzed with a mass spectrometer. Results were used to determine activation energies, reaction order, reaction rates and diffusion effects. Surface area and electron microscopic analyses were also performed on char produced from the solvent extraction residue.

Elemental and thermo-chemical analysis of oil palm fronds for biomass energy conversion

NASA Astrophysics Data System (ADS)

Guangul, Fiseha Mekonnen; Sulaiman, Shaharin Anwar; Raghavan, Vijay R.

2012-06-01

Oil palm frond is the most abundant yet untapped biomass waste in Malaysia. This paper investigates the characteristics of raw oil palm fronds and its ash to evaluate its potential utilization as a biomass fuel for gasification process using single throat downdraft gasifier. The morphological nature, elemental content, proximate and ultimate analysis and calorific value were studied. Field emission scanning electron microscopy and x-ray fluorescence were used to investigate the surface morphology, elemental and mineralogical nature of oil palm frond and its ash. The results were compared with other agricultural and forestry biomass wastes. From proximate analysis volatile matter, fixed carbon and ash were found to be 83.5%, 15.2% and 1.3%, respectively on dry basis. From ultimate analysis result values of 44.58%, 4.53%, 0.71% and 0.07% for carbon, hydrogen, nitrogen and sulfur were found respectively on dry basis. Oxygen was determined by difference and found to be 48.81%. The proximate and ultimate analysis results indicate that oil palm frond is better than agricultural wastes and less than most forestry wastes to use as a feedstock in the gasification process in order to get a better quality of syngas. The amount of ash content in OPF was found to be much less than in agricultural wastes and higher than most forestry wastes. From x-ray fluorescence analysis CaO and K2O were found as the major oxides in oil palm fronds and rice husk ash with the amount of 28.46% and 15.71% respectively. The overall results of oil palm fronds were found to be satisfactory to use as a feedstock for the process of gasification.

Advanced Systems for Preprocessing and Characterizing Coal-Biomass Mixtures as Next-Generation Fuels and Feedstocks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karmis, Michael; Luttrell, Gerald; Ripepi, Nino

The research activities presented in this report are intended to address the most critical technical challenges pertaining to coal-biomass briquette feedstocks. Several detailed investigations were conducted using a variety of coal and biomass feedstocks on the topics of (1) coal-biomass briquette production and characterization, (2) gasification of coal-biomass mixtures and briquettes, (3) combustion of coal-biomass mixtures and briquettes, and (4) conceptual engineering design and economic feasibility of briquette production. The briquette production studies indicate that strong and durable co-firing feedstocks can be produced by co-briquetting coal and biomass resources commonly available in the United States. It is demonstrated that binderlessmore » coal-biomass briquettes produced at optimized conditions exhibit very high strength and durability, which indicates that such briquettes would remain competent in the presence of forces encountered in handling, storage and transportation. The gasification studies conducted demonstrate that coal-biomass mixtures and briquettes are exceptional gasification feedstocks, particularly with regard to the synergistic effects realized during devolatilization of the blended materials. The mixture combustion studies indicate that coal-biomass mixtures are exceptional combustion feedstocks, while the briquette combustion study indicates that the use of blended briquettes reduces NO x, CO 2, and CO emissions, and requires the least amount of changes in the operating conditions of an existing coal-fired power plant. Similar results were obtained for the physical durability of the pilot-scale briquettes compared to the bench-scale tests. Finally, the conceptual engineering and feasibility analysis study for a commercial-scale briquetting production facility provides preliminary flowsheet and cost simulations to evaluate the various feedstocks, equipment selection and operating parameters.« less

Porous filtering media comparison through wet and dry sampling of fixed bed gasification products

NASA Astrophysics Data System (ADS)

Allesina, G.; Pedrazzi, S.; Montermini, L.; Giorgini, L.; Bortolani, G.; Tartarini, P.

2014-11-01

The syngas produced by fixed bed gasifiers contains high quantities of particulate and tars. This issue, together with its high temperature, avoids its direct exploitation without a proper cleaning and cooling process. In fact, when the syngas produced by gasification is used in an Internal Combustion engine (IC), the higher the content of tars and particulate, the higher the risk to damage the engine is. If these compounds are not properly removed, the engine may fail to run. A way to avoid engine fails is to intensify the maintenance schedule, but these stops will reduce the system profitability. From a clean syngas does not only follow higher performance of the generator, but also less pollutants in the atmosphere. When is not possible to work on the gasification reactions, the filter plays the most important role in the engine safeguard process. This work is aimed at developing and comparing different porous filters for biomass gasifiers power plants. A drum filter was developed and tested filling it with different filtering media available on the market. As a starting point, the filter was implemented in a Power Pallet 10 kW gasifier produced by the California-based company "ALL Power Labs". The original filter was replaced with different porous biomasses, such as woodchips and corn cobs. Finally, a synthetic zeolites medium was tested and compared with the biological media previously used. The Tar Sampling Protocol (TSP) and a modified "dry" method using the Silica Gel material were applied to evaluate the tars, particulate and water amount in the syngas after the filtration process. Advantages and disadvantages of every filtering media chosen were reported and discussed.

Literature survey of properties of synfuels derived from coal

NASA Technical Reports Server (NTRS)

Flores, F.

1982-01-01

A literature survey of the properties of synfuels for ground-based turbine applications is presented. The four major concepts for converting coal into liquid fuels (solvent extraction, catalytic liquefaction, pyrolysis, and indirect liquefaction), and the most important concepts for coal gasification (fixed bed, fluidized bed, entrained flow, and underground gasification) are described. Upgrading processes for coal derived liquid fuels are also described. Data presented for liquid fuels derived from various processes, including H-coal, synthoil, solvent refined coal, COED, donor solvent, zinc chloride hydrocracking, co-steam, and flash pyrolysis. Typical composition, and property data is also presented for low and medium-BTU gases derived from the various coal gasification processes.

Systems Analysis Of Advanced Coal-Based Power Plants

NASA Technical Reports Server (NTRS)

Ferrall, Joseph F.; Jennings, Charles N.; Pappano, Alfred W.

1988-01-01

Report presents appraisal of integrated coal-gasification/fuel-cell power plants. Based on study comparing fuel-cell technologies with each other and with coal-based alternatives and recommends most promising ones for research and development. Evaluates capital cost, cost of electricity, fuel consumption, and conformance with environmental standards. Analyzes sensitivity of cost of electricity to changes in fuel cost, to economic assumptions, and to level of technology. Recommends further evaluation of integrated coal-gasification/fuel-cell integrated coal-gasification/combined-cycle, and pulverized-coal-fired plants. Concludes with appendixes detailing plant-performance models, subsystem-performance parameters, performance goals, cost bases, plant-cost data sheets, and plant sensitivity to fuel-cell performance.

NANOMATERIAL SOLUTIONS FOR HOT COAL GAS CLEANUP - PHASE I

EPA Science Inventory

Integrated gasification combined cycle (IGCC) is a new coal gasification technique that efficiently uses the hot (900-1500°C) generated syngas to power both steam and gas turbines. Due to regulations, this syngas must be free of sulfur and purification is normally carried ...

Evaluation of two different alternatives of energy recovery from municipal solid waste in Brazil.

PubMed

Medina Jimenez, Ana Carolina; Nordi, Guilherme Henrique; Palacios Bereche, Milagros Cecilia; Bereche, Reynaldo Palacios; Gallego, Antonio Garrido; Nebra, Silvia Azucena

2017-11-01

Brazil has a large population with a high waste generation. The municipal solid waste (MSW) generated is deposited mainly in landfills. However, a considerable fraction of the waste is still improperly disposed of in dumpsters. In order to overcome this inadequate deposition, it is necessary to seek alternative routes. Between these alternatives, it is possible to quote gasification and incineration. The objective of this study is to compare, from an energetic and economic point of view, these technologies, aiming at their possible implementation in Brazilian cities. A total of two configurations were evaluated: (i) waste incineration with energy recovery and electricity production in a steam cycle; and (ii) waste gasification, where the syngas produced is used as fuel in a boiler of a steam cycle for electricity production. Simulations were performed assuming the same amount of available waste for both configurations, with a composition corresponding to the MSW from Santo André, Brazil. The thermal efficiencies of the gasification and incineration configurations were 19.3% and 25.1%, respectively. The difference in the efficiencies was caused by the irreversibilities associated with the gasification process, and the additional electricity consumption in the waste treatment step. The economic analysis presented a cost of electrical energy produced of 0.113 (US$ kWh -1 ) and 0.139 (US$ kWh -1 ) for the incineration and gasification plants respectively.

Modeling of the reburning process using sewage sludge-derived syngas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Werle, Sebastian, E-mail: sebastian.werle@polsl.pl

2012-04-15

Highlights: Black-Right-Pointing-Pointer Gasification provides an attractive method for sewage sludges treatment. Black-Right-Pointing-Pointer Gasification generates a fuel gas (syngas) which can be used as a reburning fuel. Black-Right-Pointing-Pointer Reburning potential of sewage sludge gasification gases was defined. Black-Right-Pointing-Pointer Numerical simulation of co-combustion of syngases in coal fired boiler has been done. Black-Right-Pointing-Pointer Calculation shows that analysed syngases can provide higher than 80% reduction of NO{sub x}. - Abstract: Gasification of sewage sludge can provide clean and effective reburning fuel for combustion applications. The motivation of this work was to define the reburning potential of the sewage sludge gasification gas (syngas). Amore » numerical simulation of the co-combustion process of syngas in a hard coal-fired boiler was done. All calculations were performed using the Chemkin programme and a plug-flow reactor model was used. The calculations were modelled using the GRI-Mech 2.11 mechanism. The highest conversions for nitric oxide (NO) were obtained at temperatures of approximately 1000-1200 K. The combustion of hard coal with sewage sludge-derived syngas reduces NO emissions. The highest reduction efficiency (>90%) was achieved when the molar flow ratio of the syngas was 15%. Calculations show that the analysed syngas can provide better results than advanced reburning (connected with ammonia injection), which is more complicated process.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bartke, T.C.

Under the US Department of Energy's Underground-Coal-Conversion program, four field tests were completed in 1979 and preparations were begun in 1980 for two additional field tests to be operated in 1981. The Laramie Energy Technology Center (LETC) and Sandia National Laboratories (SNL) completed Hanna IV, an air gasification test in Wyoming subbituminous coal. The Morgantown Energy Technology Center (METC) completed Pricetown 1, an air gasification test in West Virginia bituminous coal. Lawrence Livermore National Laboratory (LLNL) completed Hoe Creek 3, a steam-oxygen gasification test in Wyoming subbituminous coal. Gulf Research and Development Co. completed Steeply Dipping Beds (SDB) Test 1,more » primarily an air gasification test in Wyoming subbituminous coal and the first SDB test in the US. In 1980, Gulf R and D Co. began preparation of SDB Test 2, scheduled for operation in the fall of 1981. The DOE project teams at LETC, METC, LLNL, and SNL, in association with the Washington Irrigation and Development Co. (WIDCo), Washington Water Power (WWP), and the State of Washington, are preparing a field test site in the Centralia-Chehalis coal district of Washington. A series of large coal block tests will be completed prior to the field test, scheduled for operation in 1982 or 1983. This field test will utilize a directionally drilled link and steam-oxygen gasification system. This paper summarizes the results of the four recently completed field tests and the plans for additional tests.« less

Refuse Derived Fuel (RDF) production and gasification in a pilot plant integrated with an Otto cycle ICE through Aspen plus™ modelling: Thermodynamic and economic viability.

PubMed

Násner, Albany Milena Lozano; Lora, Electo Eduardo Silva; Palacio, José Carlos Escobar; Rocha, Mateus Henrique; Restrepo, Julian Camilo; Venturini, Osvaldo José; Ratner, Albert

2017-11-01

This work deals with the development of a Refuse Derived Fuel (RDF) gasification pilot plant using air as a gasification agent. A downdraft fixed bed reactor is integrated with an Otto cycle Internal Combustion Engine (ICE). Modelling was carried out using the Aspen Plus™ software to predict the ideal operational conditions for maximum efficiency. Thermodynamics package used in the simulation comprised the Non-Random Two-Liquid (NRTL) model and the Hayden-O'Connell (HOC) equation of state. As expected, the results indicated that the Equivalence Ratio (ER) has a direct influence over the gasification temperature and the composition of the Raw Produced Gas (RPG), and effects of ER over the Lower Heating Value (LHV) and Cold Gasification Efficiency (CGE) of the RPG are also discussed. A maximum CGE efficiency of 57-60% was reached for ER values between 0.25 and 0.3, also an average reactor temperature values in the range of 680-700°C, with a peak LHV of 5.8MJ/Nm 3 . RPG was burned in an ICE, reaching an electrical power of 50kW el . The economic assessment of the pilot plant implementation was also performed, showing the project is feasible, with power above 120kW el with an initial investment of approximately US$ 300,000. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optimization and economic evaluation of industrial gas production and combined heat and power generation from gasification of corn stover and distillers grains.

PubMed

Kumar, Ajay; Demirel, Yasar; Jones, David D; Hanna, Milford A

2010-05-01

Thermochemical gasification is one of the most promising technologies for converting biomass into power, fuels and chemicals. The objectives of this study were to maximize the net energy efficiency for biomass gasification, and to estimate the cost of producing industrial gas and combined heat and power (CHP) at a feedrate of 2000kg/h. Aspen Plus-based model for gasification was combined with a CHP generation model, and optimized using corn stover and dried distillers grains with solubles (DDGS) as the biomass feedstocks. The cold gas efficiencies for gas production were 57% and 52%, respectively, for corn stover and DDGS. The selling price of gas was estimated to be $11.49 and $13.08/GJ, respectively, for corn stover and DDGS. For CHP generation, the electrical and net efficiencies were as high as 37% and 88%, respectively, for corn stover and 34% and 78%, respectively, for DDGS. The selling price of electricity was estimated to be $0.1351 and $0.1287/kWh for corn stover and DDGS, respectively. Overall, high net energy efficiencies for gas and CHP production from biomass gasification can be achieved with optimized processing conditions. However, the economical feasibility of these conversion processes will depend on the relative local prices of fossil fuels. Copyright 2009 Elsevier Ltd. All rights reserved.

Conversion of cellulosic wastes to liquid hydrocarbon fuels. Progress report, January-February 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuester, J.L.

1981-01-01

The following materials were processed thru gasification: sugarcane bagasse, smooth sumac, coralberry, wild bergamot, pokeweed, cornstarch, Portugese oak cork and hog fuel. A data summary is given. The high H/sub 2//CO ratio at low temperature for pokeweed is of significance (>T, >H/sub 2/). Also the high olefin content of Portugese oak cork (commercial cork) is of major interest. The most promising feedstock to date with regard to synthesis gas composition has been guayule cork. A comparison of data for the two cork materials is given. A detailed breakdown for corn starch is given revealing an exceptionally high methane content (35.50more » mole %). (MHR)« less

Modification of biochar for functionality improvement in soils

NASA Astrophysics Data System (ADS)

Zwart, Kor; Kuikman, Peter; Ross, Anrew; Takaya, Chibi; Singh, Surjit; Kocaturk, Pelin; Visser, Rian

2014-05-01

Application of biochar to soils is generally considered and practiced in order to improve specific soil functions such as CEC, moisture and nutrient retention and providing additional habitat for micro-organisms. Improvement of these soil functions should lead to a higher crop yield. This would be added value to the long term sequestration of carbon in soils and contribution to renewable energy from producing and using biochar. The concept of using biochar for soil amendment is predicated on biochar behaving in a similar manner as soil organic matter (SOM) does. However, if one critically compares the properties of biochar with the properties of SOM, it is evident that biochar is rather different from SOM [Zwart, 2013 ;Zwart & Kuikman, 2013]. We have has produced a range of biochar from different feedstock using pyrolysis, gasification and hydrothermal carbonisation resulting in chars with significantly different properties. The project also investigates and tested several possibilities for improving the functionality of biochar in soils by either(i) selection of feedstock, (ii), selection of processing conditions and (iii) chemical and physical modification of biochar during and after the production process. Post modification includes the chemical treatment of biochars with either H2O2, KOH, H2SO4 and transitional metals such as Fe and investigates their effect on surface functionality, porosity, surface area, CEC and phosphate sorption. The influence of the addition of chemical modifiers and oxidants during pyrolysis and gasification has also been investigated and their effect on surface functionality determined using similar techniques. The influence of the original biomass structure on the morphology of the resultant biochars has been investigated using scanning electron microscopy.

Gasification of hybrid feedstock using animal manures and hays

USDA-ARS?s Scientific Manuscript database

The objective of this study is to evaluate the efficiency of a proprietary integrated gasification-internal combustion system in producing electricity from mixtures of animal manures such as swine solids, chicken litter, and hays. Five to 10 gallons of mixtures of swine manure, chicken litter, and h...

Chemical characterization of chars developed from thermochemical treatment of Kentucky bluegrass seed screenings

USDA-ARS?s Scientific Manuscript database

Char produced from the gasification of post-seed harvest Kentucky bluegrass residues could be recycled to a cropping system as a soil amendment if chemical characterization determined that the gasification process had not produced or concentrated deleterious chemical or physical factors that might h...

Production of hydrogen by direct gasification of coal with steam using nuclear heat

NASA Technical Reports Server (NTRS)

1975-01-01

Problems related to: (1) high helium outlet temperature of the reactor, and (2) gas generator design used in hydrogen production are studied. Special attention was given to the use of Oklahoma coal in the gasification process. Plant performance, operation, and environmental considerations are covered.

Retention of elemental mercury in fly ashes in different atmospheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

M.A. Lopez-Anton; M. Diaz-Somoano; M.R. Martinez-Tarazona

2007-01-15

Mercury is an extremely volatile element, which is emitted from coal combustion to the environment mostly in the vapor phase. To avoid the environmental problems that the toxic species of this element may cause, control technologies for the removal of mercury are necessary. Recent research has shown that certain fly ash materials have an affinity for mercury. Moreover, it has been observed that fly ashes may catalyze the oxidation of elemental mercury and facilitate its capture. However, the exact nature of Hg-fly ash interactions is still unknown, and mercury oxidation through fly ash needs to be investigated more thoroughly. Inmore » this work, the influence of a gas atmosphere on the retention of elemental mercury on fly ashes of different characteristics was evaluated. The retention capacity was estimated comparatively in inert and two gas atmospheres containing species present in coal gasification and coal combustion. Fly ashes produced in two pulverized coal combustion (PCC) plants, produced from coals of different rank (CTA and CTSR), and a fly ash (CTP) produced in a fluidized bed combustion (FBC) plant were used as raw materials. The mercury retention capacity of these fly ashes was compared to the retention obtained in different activated carbons. Although the capture of mercury is very similar in the gasification atmosphere and N{sub 2}, it is much more efficient in a coal combustion retention, being greater in fly ashes from PCC than those from FBC plants. 22 refs., 6 figs., 3 tabs.« less

Durable regenerable sorbent pellets for removal of hydrogen sulfide from coal gas

DOEpatents

Siriwardane, R.V.

1999-02-02

Pellets for removing hydrogen sulfide from a coal gasification stream at an elevated temperature are prepared in durable form, usable over repeated cycles of absorption and regeneration. The pellets include a material reactive with hydrogen sulfide, in particular zinc oxide, a binder, and an inert material, in particular calcium sulfate (drierite), having a particle size substantially larger than other components of the pellets. A second inert material and a promoter may also be included. Preparation of the pellets may be carried out by dry, solid-state mixing of components, moistening the mixture, and agglomerating it into pellets, followed by drying and calcining. Pellet size is selected, depending on the type of reaction bed for which the pellets are intended. The use of inert material with a large particle size provides a stable pellet structure with increased porosity, enabling effective gas contact and prolonged mechanical durability.

Durable regenerable sorbent pellets for removal of hydrogen sulfide from coal gas

DOEpatents

Siriwardane, R.V.

1997-12-30

Pellets for removing hydrogen sulfide from a coal gasification stream at an elevated temperature are prepared in durable form usable over repeated cycles of absorption and regeneration. The pellets include a material reactive with hydrogen sulfide, in particular zinc oxide, a binder, and an inert material, in particular calcium sulfate (drierite), having a particle size substantially larger than other components of the pellets. A second inert material and a promoter may also be included. Preparation of the pellets may be carried out by dry, solid-state mixing of components, moistening the mixture, and agglomerating it into pellets, followed by drying and calcining. Pellet size is selected, depending on the type of reaction bed for which the pellets are intended. The use of inert material with a large particle size provides a stable pellet structure with increased porosity, enabling effective gas contact and prolonged mechanical durability.

Durable regenerable sorbent pellets for removal of hydrogen sulfide from coal gas

DOEpatents

Siriwardane, Ranjani V.

1997-01-01

Pellets for removing hydrogen sulfide from a coal gasification stream at an elevated temperature are prepared in durable form usable over repeated cycles of absorption and regeneration. The pellets include a material reactive with hydrogen sulfide, in particular zinc oxide, a binder, and an inert material, in particular calcium sulfate (drierite), having a particle size substantially larger than other components of the pellets. A second inert material and a promoter may also be included. Preparation of the pellets may be carried out by dry, solid-state mixing of components, moistening the mixture, and agglomerating it into pellets, followed by drying and calcining. Pellet size is selected, depending on the type of reaction bed for which the pellets are intended. The use of inert material with a large particle size provides a stable pellet structure with increased porosity, enabling effective gas contact and prolonged mechanical durability.

Durable regenerable sorbent pellets for removal of hydrogen sulfide coal gas

DOEpatents

Siriwardane, Ranjani V.

1999-01-01

Pellets for removing hydrogen sulfide from a coal gasification stream at an elevated temperature are prepared in durable form, usable over repeated cycles of absorption and regeneration. The pellets include a material reactive with hydrogen sulfide, in particular zinc oxide, a binder, and an inert material, in particular calcium sulfate (drierite), having a particle size substantially larger than other components of the pellets. A second inert material and a promoter may also be included. Preparation of the pellets may be carried out by dry, solid-state mixing of components, moistening the mixture, and agglomerating it into pellets, followed by drying and calcining. Pellet size is selected, depending on the type of reaction bed for which the pellets are intended. The use of inert material with a large particle size provides a stable pellet structure with increased porosity, enabling effective gas contact and prolonged mechanical durability.

Fluidized bed gasification of extracted coal

DOEpatents

Aquino, Dolores C.; DaPrato, Philip L.; Gouker, Toby R.; Knoer, Peter

1986-01-01

Coal or similar carbonaceous solids are extracted by contacting the solids in an extraction zone (12) with an aqueous solution having a pH above 12.0 at a temperature between 65.degree. C. and 110.degree. C. for a period of time sufficient to remove bitumens from the coal into said aqueous solution and the extracted solids are then gasified at an elevated pressure and temperature in a fluidized bed gasification zone (60) wherein the density of the fluidized bed is maintained at a value above 160 kg/m.sup.3. In a preferred embodiment of the invention, water is removed from the aqueous solution in order to redeposit the extracted bitumens onto the solids prior to the gasification step.

Trash to Gas: Converting Space Waste into Useful Supply Products

NASA Technical Reports Server (NTRS)

Tsoras, Alexandra

2013-01-01

The cost of sending mass into space with current propulsion technology is very expensive, making every item a crucial element of the space mission. It is essential that all materials be used to their fullest potential. Items like food, packaging, clothing, paper towels, gloves, etc., normally become trash and take up space after use. These waste materials are currently either burned up upon reentry in earth's atmosphere or sent on cargo return vehicles back to earth: a very wasteful method. The purpose of this project was to utilize these materials and create useful products like water and methane gas, which is used for rocket fuel, to further supply a deep space mission. The system used was a thermal degradation reactor with the configuration of a down-draft gasifier. The reactor was loaded with approximately 100g of trash simulant and heated with two external ceramic heaters with separate temperature control in order to create pyrolysis and gasification in one zone and incineration iri a second zone simultaneously. Trash was loaded into the top half of the reactor to undergo pyrolysis while the downdraft gas experienced gasification or incineration to treat tars and maximize the production of carbon dioxide. Minor products included carbon monoxide, methane, and other hydrocarbons. The carbon dioxide produced can be sent to a Sabatier reactor to convert the gas into methane, which can be used as rocket propellant. In order to maximize the carbon dioxide and useful gases produced, and minimize the unwanted tars and leftover ashen material, multiple experiments were performed with altered parameters such as differing temperatures, flow rates, and location of inlet air flow. According to the data received from these experiments, the process will be further scaled up and optimized to ultimately create a system that reduces trash buildup while at the same time providing enough useful gases to potentially fill a methane tank that could fuel a lunar ascent vehicle or other deep space mission.

Coal gasification systems engineering and analysis. Appendix G: Commercial design and technology evaluation

NASA Technical Reports Server (NTRS)

1980-01-01

A technology evaluation of five coal gasifier systems (Koppers-Totzek, Texaco, Babcock and Wilcox, Lurgi and BGC/Lurgi) and procedures and criteria for evaluating competitive commercial coal gasification designs is presented. The technology evaluation is based upon the plant designs and cost estimates developed by the BDM-Mittelhauser team.

Hydrogen production from coal

NASA Technical Reports Server (NTRS)

1975-01-01

The gasification reactions necessary for the production of hydrogen from montana subbituminous coal are presented. The coal composition is given. The gasifier types mentioned include: suspension (entrained) combustion; fluidized bed; and moving bed. Each gasification process is described. The steam-iron process, raw and product gas compositions, gasifier feed quantities, and process efficiency evaluations are also included.

Dry coal feeder development program at Ingersoll-Rand Research, Incorporated. [for coal gasification systems

NASA Technical Reports Server (NTRS)

Mistry, D. K.; Chen, T. N.

1977-01-01

A dry coal screw feeder for feeding coal into coal gasification reactors operating at pressures up to 1500 psig is described. Results on the feeder under several different modes of operation are presented. In addition, three piston feeder concepts and their technical and economical merits are discussed.

Hydrogen manufacture by Lurgi gasification of Oklahoma coal

NASA Technical Reports Server (NTRS)

1975-01-01

Advantages and disadvantages of using the Lurgi gasification process to produce hydrogen from Oklahoma coal are listed. Special attention was given to the production of heat for the process; heat is generated by burning part of pretreated coal in the steam generator. Overall performance of the Lurgi process is summarized in tabular form.

Micro-scale Plasma Arc Gasification for Waste Treatment and Energy Production Project

NASA Technical Reports Server (NTRS)

Caraccio, Anne

2015-01-01

As NASA continues to develop technology for spaceflight beyond low earth orbit, we must develop the right systems for sustaining human life on a long duration or planetary mission. Plasma arc gasification (PAG) is an energy efficient mechanism of waste management for power generation and synthetic gas(syngas) production.

Changes in soil chemistry following wood and grass biochar amendments to an acidic agricultural production soil

USDA-ARS?s Scientific Manuscript database

The utility of biochars produced by biomass gasification for remediation of acidic production soils and plant growth in general is not as well known compared to effects from biochars resulting from pyrolysis. Recent characterization of biochar produced from gasification of Kentucky bluegrass (Poa pr...

Comprehensive Model of Single Particle Pulverized Coal Combustion Extended to Oxy-Coal Conditions

DOE PAGES

Holland, Troy; Fletcher, Thomas H.

2017-02-22

Oxy-fired coal combustion is a promising potential carbon capture technology. Predictive CFD simulations are valuable tools in evaluating and deploying oxy-fuel and other carbon capture technologies either as retrofit technologies or for new construction. But, accurate predictive simulations require physically realistic submodels with low computational requirements. In particular, comprehensive char oxidation and gasification models have been developed that describe multiple reaction and diffusion processes. Our work extends a comprehensive char conversion code (CCK), which treats surface oxidation and gasification reactions as well as processes such as film diffusion, pore diffusion, ash encapsulation, and annealing. In this work several submodels inmore » the CCK code were updated with more realistic physics or otherwise extended to function in oxy-coal conditions. Improved submodels include the annealing model, the swelling model, the mode of burning parameter, and the kinetic model, as well as the addition of the chemical percolation devolatilization (CPD) model. We compare our results of the char combustion model to oxy-coal data, and further compared to parallel data sets near conventional conditions. A potential method to apply the detailed code in CFD work is given.« less

Comprehensive Model of Single Particle Pulverized Coal Combustion Extended to Oxy-Coal Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, Troy; Fletcher, Thomas H.

Oxy-fired coal combustion is a promising potential carbon capture technology. Predictive CFD simulations are valuable tools in evaluating and deploying oxy-fuel and other carbon capture technologies either as retrofit technologies or for new construction. But, accurate predictive simulations require physically realistic submodels with low computational requirements. In particular, comprehensive char oxidation and gasification models have been developed that describe multiple reaction and diffusion processes. Our work extends a comprehensive char conversion code (CCK), which treats surface oxidation and gasification reactions as well as processes such as film diffusion, pore diffusion, ash encapsulation, and annealing. In this work several submodels inmore » the CCK code were updated with more realistic physics or otherwise extended to function in oxy-coal conditions. Improved submodels include the annealing model, the swelling model, the mode of burning parameter, and the kinetic model, as well as the addition of the chemical percolation devolatilization (CPD) model. We compare our results of the char combustion model to oxy-coal data, and further compared to parallel data sets near conventional conditions. A potential method to apply the detailed code in CFD work is given.« less

Combustion of liquid-fuel droplets in supercritical conditions

NASA Technical Reports Server (NTRS)

Shuen, J. S.; Yang, Vigor; Hsaio, C. C.

1992-01-01

A comprehensive analysis of liquid-fuel droplet combustion in both subcritical and supercritical environments has been conducted. The formulation is based on the complete conservation equations for both gas and liquid phases, and accommodates variable thermophysical properties, finite-rate chemical kinetics, and a full treatment of liquid-vapor phase equilibrium at the drop surface. The governing equations and associated interfacial boundary conditions are solved numerically using a fully coupled, implicit scheme with the dual time-stepping integration technique. The model is capable of treating the entire droplet history, including the transition from the subcritical to supercritical state. As a specific example, the combustion of n-pentane fuel droplets in air is studied for pressures in the range of 5-140 atm. Results indicate that the ambient gas pressure exerts significant control of droplet gasification and burning processes through its influence on fluid transport, gas-liquid interfacial thermodynamics, and chemical reactions. The droplet gasification rate increases progressively with pressure. However, the data for the overall burnout time exhibit a considerable change in the combustion mechanism at the critical pressure, mainly as a result of reduced mass diffusivity and latent heat of vaporization with increased pressure.

Combustion of liquid fuel droplets in supercritical conditions

NASA Technical Reports Server (NTRS)

Shuen, J. S.; Yang, Vigor

1991-01-01

A comprehensive analysis of liquid-fuel droplet combustion in both sub- and super-critical environments has been conducted. The formulation is based on the complete conservation equations for both gas and liquid phases, and accommodates finite-rate chemical kinetics and a full treatment of liquid-vapor phase equilibrium at the droplet surface. The governing equations and the associated interface boundary conditions are solved numerically using a fully coupled, implicit scheme with the dual time-stepping integration technique. The model is capable of treating the entire droplet history, including the transition from the subcritical to the supercritical state. As a specific example, the combustion of n-pentane fuel droplets in air is studied for pressures of 5-140 atm. Results indicate that the ambient gas pressure exerts significant control of droplet gasification and burning processes through its influences on the fluid transport, gas/liquid interface thermodynamics, and chemical reactions. The droplet gasification rate increases progressively with pressure. However, the data for the overall burnout time exhibits a significant variation near the critical burning pressure, mainly as a result of reduced mass-diffusion rate and latent heat of vaporization with increased pressure. The influence of droplet size on the burning characteristics is also noted.

Scalable fabrication of micron-scale graphene nanomeshes for high-performance supercapacitor applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Hyun-Kyung; Bak, Seong-Min; Lee, Suk Woo

Graphene nanomeshes (GNMs) with nanoscale periodic or quasi-periodic nanoholes have attracted considerable interest because of unique features such as their open energy band gap, enlarged specific surface area, and high optical transmittance. These features are useful for applications in semiconducting devices, photocatalysis, sensors, and energy-related systems. We report on the facile and scalable preparation of multifunctional micron-scale GNMs with high-density of nanoperforations by catalytic carbon gasification. The catalytic carbon gasification process induces selective decomposition on the graphene adjacent to the metal catalyst, thus forming nanoperforations. Furthermore, the pore size, pore density distribution, and neck size of the GNMs can bemore » controlled by adjusting the size and fraction of the metal oxide on graphene. The fabricated GNM electrodes exhibit superior electrochemical properties for supercapacitor (ultracapacitor) applications, including exceptionally high capacitance (253 F g -1 at 1 A g -1) and high rate capability (212 F g -1 at 100 A g -1) with excellent cycle stability (91% of the initial capacitance after 50 000 charge/discharge cycles). Moreover, the edge-enriched structure of GNMs plays an important role in achieving edge-selected and high-level nitrogen doping.« less

Scalable fabrication of micron-scale graphene nanomeshes for high-performance supercapacitor applications

DOE PAGES

Kim, Hyun-Kyung; Bak, Seong-Min; Lee, Suk Woo; ...

2016-01-27

Graphene nanomeshes (GNMs) with nanoscale periodic or quasi-periodic nanoholes have attracted considerable interest because of unique features such as their open energy band gap, enlarged specific surface area, and high optical transmittance. These features are useful for applications in semiconducting devices, photocatalysis, sensors, and energy-related systems. We report on the facile and scalable preparation of multifunctional micron-scale GNMs with high-density of nanoperforations by catalytic carbon gasification. The catalytic carbon gasification process induces selective decomposition on the graphene adjacent to the metal catalyst, thus forming nanoperforations. Furthermore, the pore size, pore density distribution, and neck size of the GNMs can bemore » controlled by adjusting the size and fraction of the metal oxide on graphene. The fabricated GNM electrodes exhibit superior electrochemical properties for supercapacitor (ultracapacitor) applications, including exceptionally high capacitance (253 F g -1 at 1 A g -1) and high rate capability (212 F g -1 at 100 A g -1) with excellent cycle stability (91% of the initial capacitance after 50 000 charge/discharge cycles). Moreover, the edge-enriched structure of GNMs plays an important role in achieving edge-selected and high-level nitrogen doping.« less

Power Systems Development Facility Gasification Test Campaing TC18

DOE Office of Scientific and Technical Information (OSTI.GOV)

Southern Company Services

2005-08-31

In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF) located in Wilsonville, Alabama, routinely demonstrates gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a KBR Transport Gasifier, a hot gas particulate control device (PCD), advanced syngas cleanup systems, and high pressure solids handling systems. This report details Test Campaign TC18 of the PSDF gasification process. Test campaign TC18 began on June 23, 2005, and ended on August 22, 2005, with the gasifiermore » train accumulating 1,342 hours of operation using Powder River Basin (PRB) subbituminous coal. Some of the testing conducted included commissioning of a new recycle syngas compressor for gasifier aeration, evaluation of PCD filter elements and failsafes, testing of gas cleanup technologies, and further evaluation of solids handling equipment. At the conclusion of TC18, the PSDF gasification process had been operated for more than 7,750 hours.« less

Two-stage high temperature sludge gasification using the waste heat from hot blast furnace slags.

PubMed

Sun, Yongqi; Zhang, Zuotai; Liu, Lili; Wang, Xidong

2015-12-01

Nowadays, disposal of sewage sludge from wastewater treatment plants and recovery of waste heat from steel industry, become two important environmental issues and to integrate these two problems, a two-stage high temperature sludge gasification approach was investigated using the waste heat in hot slags herein. The whole process was divided into two stages, i.e., the low temperature sludge pyrolysis at ⩽ 900°C in argon agent and the high temperature char gasification at ⩾ 900°C in CO2 agent, during which the heat required was supplied by hot slags in different temperature ranges. Both the thermodynamic and kinetic mechanisms were identified and it was indicated that an Avrami-Erofeev model could best interpret the stage of char gasification. Furthermore, a schematic concept of this strategy was portrayed, based on which the potential CO yield and CO2 emission reduction achieved in China could be ∼1.92∗10(9)m(3) and 1.93∗10(6)t, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

NH3 Abatement in Fluidized Bed Co-Gasification of RDF and Coal

NASA Astrophysics Data System (ADS)

Gulyurtlu, I.; Pinto, Filomena; Dias, Mário; Lopes, Helena; André, Rui Neto; Cabrita, I.

Gasification of wastes may come out as an alternative technology to produce a gas with many potential applications, from direct burning in a boiler or motor to the production of synthetic chemicals and hydrogen. High tar production and high operational costs are preventing gasification wider dissemination. Besides these problems, the presence of NH3 in the syngas may have a negative impact as it can be converted into nitrogen oxides if the gas is further burnt. To reduce NH3 formation it is required a full understanding of how operational parameters contribute to the formation/reduction of this pollutant. A full studyon the effect of fuel composition, temperature and equivalence ratio on the formation of NH3 is given. Experimental results are compared to theoretical ones obtained with FactSage software. It is also analyzed the effect of feedstock mineral matterin NH3 release during gasification. Toaccomplish a significant decrease in the release of NH3, different catalysts and sorbents were tested with the aim of achieving high energy conversions and low environmental impact.

Gasification of rice straw in a fluidized-bed gasifier for syngas application in close-coupled boiler-gasifier systems.

PubMed

Calvo, L F; Gil, M V; Otero, M; Morán, A; García, A I

2012-04-01

The feasibility and operation performance of the gasification of rice straw in an atmospheric fluidized-bed gasifier was studied. The gasification was carried out between 700 and 850 °C. The stoichiometric air-fuel ratio (A/F) for rice straw was 4.28 and air supplied was 7-25% of that necessary for stoichiometric combustion. Mass and power balances, tar concentration, produced gas composition, gas phase ammonia, chloride and potassium concentrations, agglomeration tendencies and gas efficiencies were assessed. Agglomeration was avoided by replacing the normal alumina-silicate bed by a mixture of alumina-silicate sand and MgO. It was shown that it is possible to produce high quality syngas from the gasification of rice straw. Under the experimental conditions used, the higher heating value (HHV) of the produced gas reached 5.1 MJ Nm(-3), the hot gas efficiency 61% and the cold gas efficiency 52%. The obtained results prove that rice straw may be used as fuel for close-coupled boiler-gasifier systems. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rapid co-pyrolysis of rice straw and a bituminous coal in a high-frequency furnace and gasification of the residual char.

PubMed

Yuan, Shuai; Dai, Zheng-hua; Zhou, Zhi-jie; Chen, Xue-li; Yu, Guang-suo; Wang, Fu-chen

2012-04-01

Rapid pyrolysis of rice straw (RS) and Shenfu bituminous coal (SB) separately, and rapid co-pyrolysis of RS/SB blends (mass ratio 1:4, 1:4, and 4:1), were carried out in a high-frequency furnace which can ensure both high heating rate and satisfying contact of fuel particles. Synergies between RS and SB during rapid co-pyrolysis were investigated. Intrinsic and morphological structures of residual char from co-pyrolysis, and their effects on gasification characteristics were also studied. Synergies occurred during rapid co-pyrolysis of RS and SB (RS/SB=1:4) resulting in decreasing char yields and increasing volatile yields. Synergies also happened during gasification of the char derived from co-pyrolysis of RS and SB with mass ratio of 1:4. The increased mass ratio of RS to SB did not only weaken synergies during co-pyrolysis, but significantly reduced the gasification rates of the co-pyrolysis char compared to the calculated values. Results can help to optimize co-conversion process of biomass/coal. Copyright © 2012 Elsevier Ltd. All rights reserved.

Combustion of Coal Char Particles under Fluidized Bed Oxyfiring Conditions

NASA Astrophysics Data System (ADS)

Scala, Fabrizio; Chirone, Riccardo

In this work combustion of single coal char particles was studied at 850°C in a lab-scale fluidized bed under simulated oxyfiring conditions. The burning rate of the particles was followed as a function of time by continuously measuring the outlet CO and O2 concentrations. Some preliminary evaluations on the significance of homogeneous CO oxidation in the reactor and of carbon gasification by CO2 in the char were also carried out. Results showed that the carbon burning rate increases with oxygen concentration and char particle size. The particle temperature is approximately equal to the bed one up to an oxygen concentration of 2%, but it is considerably higher for larger oxygen concentrations. Both CO2 gasification of char and homogeneous CO oxidation are not negligible. The gasification reaction rate is slow and it is likely to be controlled by intrinsic kinetics. During purely gasification conditions the extent of carbon loss due to particle attrition by abrasion (estimated from the carbon mass balance) appears to be more important than under combustion conditions.

Steam-air blown bubbling fluidized bed biomass gasification (BFBBG): Multi-scale models and experimental validation

DOE PAGES

Bates, Richard B.; Ghoniem, Ahmed F.; Jablonski, Whitney S.; ...

2017-02-02

During fluidized bed biomass gasification, complex gas-solid mixing patterns and numerous chemical and physical phenomena make identification of optimal operating conditions challenging. In this work, a parametric experimental campaign was carried out alongside the development of a coupled reactor network model which successfully integrates the individually validated sub-models to predict steady-state reactor performance metrics and outputs. The experiments utilized an integrated gasification system consisting of an externally-heated, bench-scale, 4-in., 5 kWth, fluidized bed steam/air blown gasifier fed with woody biomass equipped with a molecular beam mass spectrometer to directly measure tar species. The operating temperature (750-850°C) and air/fuel equivalence ratiomore » (ER = 0-0.157) were independently varied to isolate their effects. Elevating temperature is shown to improve the char gasification rate and reduce tar concentrations. In conclusion, air strongly impacts the composition of tar, accelerating the conversion of lighter polycyclic-aromatic hydrocarbons into soot precursors, while also improving the overall carbon conversion.« less

Role of steel slags on biomass/carbon dioxide gasification integrated with recovery of high temperature heat.

PubMed

Sun, Yongqi; Liu, Qianyi; Wang, Hao; Zhang, Zuotai; Wang, Xidong

2017-01-01

Disposal of biomass in the agriculture and steel slags in the steel industry provides a significant solution toward sustainability in China. Herein these two sectors were creatively combined as a novel method, i.e., biomass/CO 2 gasification using waste heat from hot slags where the influence of chemical compositions of steel slags, characterized as iron oxide content and basicity, on gasification thermodynamics, was systemically reported for the first time. Both the target gases of CO, H 2 and CH 4 and the polluted gases of NH 3 , NO and NO 2 were considered. It was first found that an increasing iron content and slag basicity continuously improved the CO yield at 600-1000°C and 800-1000°C, respectively; while the effect on polluted gas releases was limited. Moreover, the solid wastes after gasification could be utilized to provide nutrients and improve the soil in the agriculture, starting from which an integrated modern system was proposed herein. Copyright © 2016 Elsevier Ltd. All rights reserved.

Production of oxygen from lunar ilmenite

NASA Technical Reports Server (NTRS)

Zhao, Y.; Shadman, F.

1990-01-01

The following subjects are addressed: (1) the mechanism and kinetics of carbothermal reduction of simulated lunar ilmenite using carbon and, particularly, CO as reducing agents; (2) the determination of the rate-limiting steps; (3) the investigation of the effect of impurities, particularly magnesium; (4) the search for catalysts suitable for enhancement of the rate-limiting step; (5) the comparison of the kinetics of carbothermal reduction with those of hydrogen reduction; (6) the study of the combined use of CO and hydrogen as products of gasification of carbonaceous solids; (7) the development of reduction methods based on the use of waste carbonaceous compounds for the process; (8) the development of a carbothermal reaction path that utilizes gasification of carbonaceous solids to reducing gaseous species (hydrocarbons and carbon monoxide) to facilitate the reduction reaction kinetics and make the process more flexible in using various forms of carbonaceous feeds; (9) the development of advanced gas separation techniques, including the use of high-temperature ceramic membranes; (10) the development of an optimum process flow sheet for carbothermal reduction, and comparison of this process with the hydrogen reduction scheme, as well as a general comparison with other leading oxygen production schemes; and (11) the use of new and advanced material processing and separation techniques.

The O₂-enriched air gasification of coal, plastics and wood in a fluidized bed reactor.

PubMed

Mastellone, Maria Laura; Zaccariello, Lucio; Santoro, Donato; Arena, Umberto

2012-04-01

The effect of oxygen-enriched air during fluidized bed co-gasification of a mixture of coal, plastics and wood has been investigated. The main components of the obtained syngas were measured by means of on-line analyzers and a gas chromatograph while those of the condensate phase were off-line analysed by means of a gas chromatography-mass spectrometer (GC-MS). The characterization of condensate phase as well as that of the water used as scrubbing medium completed the performed diagnostics. The experimental results were further elaborated in order to provide material and substances flow analyses inside the plant boundaries. These analyses allowed to obtain the main substance distribution between solid, gaseous and condensate phases and to estimate the conversion efficiency of carbon and hydrogen but also to easily visualise the waste streams produced by the process. The process performance was then evaluated on the basis of parameters related to the conversion efficiency of fuels into valuable products (i.e. by considering tar and particulate as process losses) as well as those related to the energy recovery. Copyright © 2011 Elsevier Ltd. All rights reserved.

Gasification: An alternative solution for energy recovery and utilization of vegetable market waste.

PubMed

Narnaware, Sunil L; Srivastava, Nsl; Vahora, Samir

2017-03-01

Vegetables waste is generally utilized through a bioconversion process or disposed of at municipal landfills, dumping sites or dumped on open land, emitting a foul odor and causing health hazards. The presents study deals with an alternative way to utilize solid vegetable waste through a thermochemical route such as briquetting and gasification for its energy recovery and subsequent power generation. Briquettes of 50 mm diameter were produced from four different types of vegetable waste. The bulk density of briquettes produced was increased 10 to 15 times higher than the density of the dried vegetable waste in loose form. The lower heating value (LHV) of the briquettes ranged from 10.26 MJ kg -1 to 16.60 MJ kg -1 depending on the type of vegetable waste. The gasification of the briquettes was carried out in an open core downdraft gasifier, which resulted in syngas with a calorific value of 4.71 MJ Nm -3 at the gasification temperature between 889°C and 1011°C. A spark ignition, internal combustion engine was run on syngas and could generate a maximum load up to 10 kW e . The cold gas efficiency and the hot gas efficiency of the gasifier were measured at 74.11% and 79.87%, respectively. Energy recovery from the organic vegetable waste was possible through a thermochemical conversion route such as briquetting and subsequent gasification and recovery of the fuel for small-scale power generation.

Calcium silicate cement sorbent for H/sub 2/S removal and improved gasification processes. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoo, H.J.; Steinberg, M.

1983-10-01

Based on the studies performed on the agglomerated cement sorbent (ACS) pellet for in-situ desulfurization of gases and for improved gasification, in low and medium Btu fluidized bed coal gasifier (FBG) systems, the following conclusions can be drawn: (1) The pelletization method by a drum pelletizer is a good way of agglomerating large sized (>20 US mesh) ACS pellets having high sorbent performance. (2) The ACS pellets have a sulfur capture capacity of about 60% at 950/sup 0/C, are 100% regenerable, and so not lose reactivity during cyclic use. (3) The rate of sulfidation increases linearly with H/sub 2/S concentrationmore » in the feed gas stream up to 1.0%. (4) The rate of sulfidation first increases with temperature in an Arrhenius fashion in the temperature range of 800/sup 0/C to 1000/sup 0/C and then decreases with further increase in temperatures, giving rise to an optimum sulfidation temperature of about 1000/sup 0/C. (5) The gasification of coal or coal char either with CO/sub 2/ gas or by partial oxidation in a 40 mm ID FBG shows that the gasification efficiency of coal (or coal char) is very much enhanced with the ACS pellets and with Greer limestone over the coal (or coal char) alone. There is, however, not much difference between the ACS pellets and Greer limestone in the degree of enhancement. (6) The gasification of coal by partial oxidation with air to low Btu gas in a 1-inch coal-fired FBG unit shows that in the temperature range of 800/sup 0/ to 900/sup 0/C the efficiency of coal gasification is improved by as much as 40% when ACS pellets are used compared to the use of Greer limestone. At the same time the sulfur removal efficiency is increased from 50 to 65% with Greer limestone to over 95% with the ACS pellets.« less

Process of producing liquid hydrocarbon fuels from biomass

DOEpatents

Kuester, J.L.

1987-07-07

A continuous thermochemical indirect liquefaction process is described to convert various biomass materials into diesel-type transportation fuels which fuels are compatible with current engine designs and distribution systems comprising feeding said biomass into a circulating solid fluidized bed gasification system to produce a synthesis gas containing olefins, hydrogen and carbon monoxide and thereafter introducing the synthesis gas into a catalytic liquefaction system to convert the synthesis gas into liquid hydrocarbon fuel consisting essentially of C[sub 7]-C[sub 17] paraffinic hydrocarbons having cetane indices of 50+. 1 fig.

Biomass energy production. Citations from the International Aerospace Abstracts data base

NASA Technical Reports Server (NTRS)

Moore, P. W.

1980-01-01

These 210 citations from the international literature describe the production and/or utilization of most forms of biomass as a source of energy, fuel, food, and chemical intermediates or feedstocks. Biomass conversion by incineration, gasification, pyrolysis, hydrolysis, anaerobic digestion, or fermentation, as well as by catalytic, photosynthetic, chemosynthetic, and bio-electrochemical means are among the conversion processes considered. Discussions include biomass plantation and material productivity, transportation and equipment requirements, effects, comparisons of means and efficiencies of utilization and conversion, assessments of limitations, and evaluations of economic potential.

GTI

DOE Office of Scientific and Technical Information (OSTI.GOV)

GTI

Biomass represents a large potential feedstock resource for environmentally clean processes that produce power or chemicals. It lends itself to both biological and thermal conversion processes and both options are currently being explored. Hydrogen can be produced in a variety of ways. The majority of the hydrogen produced in this country is produced through natural gas reforming and is used as chemical feedstock in refinery operations. In this report we will examine the production of hydrogen by gasification of biomass. Biomass is defined as organic matter that is available on a renewable basis through natural processes or as a by-productmore » of processes that use renewable resources. The majority of biomass is used in combustion processes, in mills that use the renewable resources, to produce electricity for end-use product generation. This report will explore the use of hydrogen as a fuel derived from gasification of three candidate biomass feedstocks: bagasse, switchgrass, and a nutshell mix that consists of 40% almond nutshell, 40% almond prunings, and 20% walnut shell. In this report, an assessment of the technical and economic potential of producing hydrogen from biomass gasification is analyzed. The resource base was assessed to determine a process scale from feedstock costs and availability. Solids handling systems were researched. A GTI proprietary gasifier model was used in combination with a Hysys. design and simulation program to determine the amount of hydrogen that can be produced from each candidate biomass feed. Cost estimations were developed and government programs and incentives were analyzed. Finally, the barriers to the production and commercialization of hydrogen from biomass were determined. The end-use of the hydrogen produced from this system is small PEM fuel cells for automobiles. Pyrolysis of biomass was also considered. Pyrolysis is a reaction in which biomass or coal is partially vaporized by heating. Gasification is a more general term, and includes heating as well as the injection of other ''ingredients'' such as oxygen and water. Pyrolysis alone is a useful first step in creating vapors from coal or biomass that can then be processed in subsequent steps to make liquid fuels. Such products are not the objective of this project. Therefore pyrolysis was not included in the process design or in the economic analysis. High-pressure, fluidized bed gasification is best known to GTI through 30 years of experience. Entrained flow, in contrast to fluidized bed, is a gasification technology applied at much larger unit sizes than employed here. Coal gasification and residual oil gasifiers in refineries are the places where such designs have found application, at sizes on the order of 5 to 10 times larger than what has been determined for this study. Atmospheric pressure gasification is also not discussed. Atmospheric gasification has been the choice of all power system pilot plants built for biomass to date, except for the Varnamo plant in Sweden, which used the Ahlstrom (now Foster Wheeler) pressurized gasifier. However, for fuel production, the disadvantage of the large volumetric flows at low pressure leads to the pressurized gasifier being more economical.« less

Efficient volatile metal removal from low rank coal in gasification, combustion, and processing systems and methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bland, Alan E.; Sellakumar, Kumar Muthusami; Newcomer, Jesse D.

Efficient coal pre-processing systems (69) integrated with gasification, oxy-combustion, and power plant systems include a drying chamber (28), a volatile metal removal chamber (30), recirculated gases, including recycled carbon dioxide (21), nitrogen (6), and gaseous exhaust (60) for increasing the efficiencies and lowering emissions in various coal processing systems.

CHEMICALLY ACTIVE FLUID-BED PROCESS FOR SULPHUR REMOVAL DURING GASIFICATION OF HEAVY FUEL OIL - SECOND PHASE

EPA Science Inventory

The report describes the second phase of studies on the CAFB process for desulfurizing gasification of heavy fuel oil in a bed of hot lime. The first continuous pilot plant test with U.S. limestone BCR 1691 experienced local stone sintering and severe production of sticky dust du...

Biochars derived from gasified feedstocks increase the growth and improve the nutrient acquisition of Triticum aestivum (L.) grown in agricultural alfisols

USDA-ARS?s Scientific Manuscript database

The utility of biochars produced by biomass gasification for remediation of acidic production soils and plant growth in general is not as well known compared to effects from biochars resulting from pyrolysis. Our recent characterization of biochars produced from gasification of Kentucky bluegrass (P...

Agglomerating combustor-gasifier method and apparatus for coal gasification

DOEpatents

Chen, Joseph L. P.; Archer, David H.

1976-09-21

A method and apparatus for gasifying coal wherein the gasification takes place in a spout fluid bed at a pressure of about 10 to 30 atmospheres and a temperature of about 1800.degree. to 2200.degree.F and wherein the configuration of the apparatus and the manner of introduction of gases for combustion and fluidization is such that agglomerated ash can be withdrawn from the bottom of the apparatus and gas containing very low dust loading is produced. The gasification reaction is self-sustaining through the burning of a stoichiometric amount of coal with air in the lower part of the apparatus to form the spout within the fluid bed. The method and apparatus are particularly suitable for gasifying coarse coal particles.

Fluidized bed gasification of extracted coal

DOEpatents

Aquino, D.C.; DaPrato, P.L.; Gouker, T.R.; Knoer, P.

1984-07-06

Coal or similar carbonaceous solids are extracted by contacting the solids in an extraction zone with an aqueous solution having a pH above 12.0 at a temperature between 65/sup 0/C and 110/sup 0/C for a period of time sufficient to remove bitumens from the coal into said aqueous solution, and the extracted solids are then gasified at an elevated pressure and temperature in a fluidized bed gasification zone (60) wherein the density of the fluidized bed is maintained at a value above 160 kg/m/sup 3/. In a preferred embodiment of the invention, water is removed from the aqueous solution in order to redeposit the extracted bitumens onto the solids prior to the gasification step. 2 figs., 1 tab.

Methods and apparatus for catalytic hydrothermal gasification of biomass

DOEpatents

Elliott, Douglas C.; Butner, Robert Scott; Neuenschwander, Gary G.; Zacher, Alan H.; Hart, Todd R.

2012-08-14

Continuous processing of wet biomass feedstock by catalytic hydrothermal gasification must address catalyst fouling and poisoning. One solution can involve heating the wet biomass with a heating unit to a temperature sufficient for organic constituents in the feedstock to decompose, for precipitates of inorganic wastes to form, for preheating the wet feedstock in preparation for subsequent separation of sulfur contaminants, or combinations thereof. Treatment further includes separating the precipitates out of the wet feedstock, removing sulfur contaminants, or both using a solids separation unit and a sulfur separation unit, respectively. Having removed much of the inorganic wastes and the sulfur that can cause poisoning and fouling, the wet biomass feedstock can be exposed to the heterogeneous catalyst for gasification.

Fundamentals and applications of solar energy. Part 2

NASA Astrophysics Data System (ADS)

Faraq, I. H.; Melsheimer, S. S.

Applications of techniques of chemical engineering to the development of materials, production methods, and performance optimization and evaluation of solar energy systems are discussed. Solar thermal storage systems using phase change materials, liquid phase Diels-Alder reactions, aquifers, and hydrocarbon oil were examined. Solar electric systems were explored in terms of a chlorophyll solar cell, the nonequilibrium electric field effects developed at photoelectrode/electrolyte interfaces, and designs for commercial scale processing of solar cells using continuous thin-film coating production methods. Solar coal gasification processes were considered, along with multilayer absorber coatings for solar concentrator receivers, solar thermal industrial applications, the kinetics of anaerobic digestion of crop residues to produce methane, and a procedure for developing a computer simulation of a solar cooling system.