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1

Atmospheric Pressure Fluidized Bed Coal Combustion Test.  

National Technical Information Service (NTIS)

A pilot plant is realized for the combustion of coal in a fluidized bed at atmospheric pressure, with a bed cooled by immersed exchangers. Technological devices and the associated operating conditions are developed. In particular, pre-heating of the bed, ...

N. Meysson B. Grue

1982-01-01

2

Atmospheric fluidized-bed combustion coal feeding test program  

Microsoft Academic Search

Development of a coal feeding and distribution system is one of the major requirements for successful operation of large scale atmospheric fluidized-bed boilers. Since combustion efficiency, sulfur capture, and tube corrosion are strong functions of coal distribution in the bed, the reliability of the feed system is critical. One proposed coal feeding method involves underbed feed nozzles, and pneumatic conveying

C. S. Daw; J. F. Thomas; R. S. Holcomb; C. K. Andrews

1980-01-01

3

Performance of low-rank coal in atmospheric fluidized bed combustion. Technology transfer report  

Microsoft Academic Search

This report presents test data generated at GFETC and discusses the implications of this data in regard to the technical and economic feasibility of using low-rank coals in the AFBC. Atmospheric fluidized bed combustion offers a number of potential advantages over conventional pulverized coal combustion due to the intense turbulence in the fluidized bed and long residence times of solids

D. R. Hajicek; B. J. Zobeck; M. D. Mann; B. G. Miller; R. C. Ellman; S. A. Benson; G. M. Goblirsch; J. L. Cooper; J. L. Guillory; A. G. Eklund

1985-01-01

4

Fines recycle modeling for an atmospheric fluidized-bed coal combustor. Final report  

Microsoft Academic Search

A fine carbon combustion model developed by General Atomic Company (GA) was modified to predict combustion efficiencies as a function of several process variables in the Babcock and Wilcox (B and W) 6 ft by 6 ft atmospheric fluidized-bed coal combustor. The coal fines combustion kinetics were determined using the model and fines recycle test data from the 6 ft

W. L. Brimhall; D. E. Fields; W. S. Rickman

1981-01-01

5

Development progress on the atmospheric fluidized bed coal combustor for cogeneration gas turbine system for industrial cogeneration plants  

Microsoft Academic Search

The Atmospheric Fluidized Bed Coal Combustor Program will develop the technology for a fluidized bed coal combustion system to provide a source of high temperature air for process heating and power generation with gas turbines in industrial plants. The gas turbine has the advantages of a higher ratio of electric power output to exhaust heat load and a higher exhaust

R. S. Holcomb

1979-01-01

6

Steam Generator with Circulating Atmospheric Fluidized Bed Combustion.  

National Technical Information Service (NTIS)

The combustion of coal in power plants by conventional combustion techniques is studied with emphasis on combustion in a circulating atmospheric fluidized bed (CFBC). The CFBC method stays half way between the classical fluidized bed with a well defined b...

W. Wein H. Hoeffgen K. H. Maintok G. Daradimos

1982-01-01

7

Pulsed atmospheric fluidized bed combustion  

SciTech Connect

In order to verify the technical feasibility of the MTCI Pulsed Atmospheric Fluidized Bed Combustor technology, a laboratory-scale system was designed, built and tested. Important aspects of the operational and performance parameters of the system were established experimentally. A considerable amount of the effort was invested in the initial task of constructing an AFBC that would represent a reasonable baseline against which the performance of the PAFBC could be compared. A summary comparison of the performance and emissions data from the MTCI 2 ft {times} 2 ft facility (AFBC and PAFBC modes) with those from conventional BFBC (taller freeboard and recycle operation) and circulating fluidized bed combustion (CFBC) units is given in Table ES-1. The comparison is for typical high-volatile bituminous coals and sorbents of average reactivity. The values indicated for BFBC and CFBC were based on published information. The AFBC unit that was designed to act as a baseline for the comparison was indeed representative of the larger units even at the smaller scale for which it was designed. The PAFBC mode exhibited superior performance in relation to the AFBC mode. The higher combustion efficiency translates into reduced coal consumption and lower system operating cost; the improvement in sulfur capture implies less sorbent requirement and waste generation and in turn lower operating cost; lower NO{sub x} and CO emissions mean ease of site permitting; and greater steam-generation rate translates into less heat exchange surface area and reduced capital cost. Also, the PAFBC performance generally surpasses those of conventional BFBC, is comparable to CFBC in combustion and NO{sub x} emissions, and is better than CFBC in sulfur capture and CO emissions even at the scaled-down size used for the experimental feasibility tests.

Not Available

1989-11-01

8

Current State of Atmospheric Fluidized-Bed Combustion Technology.  

National Technical Information Service (NTIS)

The paper examines atmospheric fluidized-bed combustion (AFBC) technology, a coal burning method that has several environmental and technical advantages over the more conventional technologies, such as pulverized coal methods. The AFBC approach injects an...

1989-01-01

9

Pulsed atmospheric fluidized bed combustor apparatus  

DOEpatents

A pulsed atmospheric fluidized bed reactor system is disclosed and claimed along with a process for utilization of same for the combustion of, e.g. high sulfur content coal. The system affords a economical, ecologically acceptable alternative to oil and gas fired combustors. The apparatus may also be employed for endothermic reaction, combustion of waste products, e.g., organic and medical waste, drying materials, heating air, calcining and the like.

Mansour, Momtaz N. (Columbia, MD)

1993-10-26

10

Simulation and modeling of atmospheric fluidized bed combustors for high sulfur coals  

SciTech Connect

This paper briefly summarizes the state-of-the-art in Atmospheric Fluidized Bed Combustion (AFBC) modeling and uses the Oak Ridge National Laboratory (ORNL)-Tennessee Valley Authority (TVA) AFBC steady-state model as an example to illustrate how some major modeling concerns have been addressed. Other recent models are briefly described and compared with the ORNL-TVA model. The reader is referred to the references cited for details on the assumptions and computational methods. 100 refs., 8 figs., 1 tab.

Krishnan, R.P.; Daw, C.S.; Byrd, J.; Wells, J.W.

1989-01-01

11

Pulsed atmospheric fluidized bed combustion. Final report.  

National Technical Information Service (NTIS)

In order to verify the technical feasibility of the MTCI Pulsed Atmospheric Fluidized Bed Combustor technology, a laboratory-scale system was designed, built and tested. Important aspects of the operational and performance parameters of the system were es...

1989-01-01

12

Fluidized bed selective pyrolysis of coal  

DOEpatents

The present invention discloses a process for the pyrolysis of coal which comprises the effective utilization of two zonal inclined fluidized beds, where said zones can be selectively controlled as to temperature and heating rate. The first zonal inclined fluidized bed serves as a dryer for crushed coal and additionally is controlled to selectively pyrolyze said coal producing substantially carbon dioxide for recycle use. The second zonal inclined fluidized bed further pyrolyzes the coal to gaseous, liquid and char products under controlled temperature and heating rate zones designed to economically integrate the product mix. The gas and liquid products are recovered from the gaseous effluent stream while the char which remains can be further treated or utilized in a subsequent process step.

Shang, Jer Y. (McLean, VA); Cha, Chang Y. (Golden, CO); Merriam, Norman W. (Laramie, WY)

1992-01-01

13

Fluidized bed selective pyrolysis of coal  

DOEpatents

The present invention discloses a process for the pyrolysis of coal which comprises the effective utilization of two zonal inclined fluidized beds, where said zones can be selectively controlled as to temperature and heating rate. The first zonal inclined fluidized bed serves as a dryer for crushed coal and additionally is controlled to selectively pyrolyze said coal producing substantially carbon dioxide for recycle use. The second zonal inclined fluidized bed further pyrolyses the coal to gaseous, liquid and char products under controlled temperature and heating rate zones designed to economically integrate the product mix. The gas and liquid products are recovered from the gaseous effluent stream while the char which remains can be further treated or utilized in a subsequent process step. 9 figs.

Shang, J.Y.; Cha, C.Y.; Merriam, N.W.

1992-12-15

14

Nucla circulating atmospheric fluidized bed demonstration project  

SciTech Connect

Colorado-Ute Electric Association began a study to evaluate options for upgrading and extending the life of its Nucla power station in 1982. Located in southwestern Colorado near the town of Nucla, this station was commissioned in 1959 with a local bituminous coal as its design fuel for three identical stoker-fired units, each rated at 12.6 MW(e). Poor station efficiency, high fuel costs, and spiraling boiler maintenance costs forced the Nucla Station into low priority in the CUEA dispatch order as early as 1981. Among the options CUEA considered was to serve as a host utility to demonstrate Atmospheric Fluidized Bed Combustion (AFBC) technology. The anticipated environmental benefits and apparent attractive economics of a circulating AFBC led to Colorado-Ute's decision to proceed with the design and construction of a demonstration project in 1984 at the Nucla facility.

Not Available

1991-10-01

15

Pulsed atmospheric fluidized bed combustion. Final report  

SciTech Connect

In order to verify the technical feasibility of the MTCI Pulsed Atmospheric Fluidized Bed Combustor technology, a laboratory-scale system was designed, built and tested. Important aspects of the operational and performance parameters of the system were established experimentally. A considerable amount of the effort was invested in the initial task of constructing an AFBC that would represent a reasonable baseline against which the performance of the PAFBC could be compared. A summary comparison of the performance and emissions data from the MTCI 2 ft {times} 2 ft facility (AFBC and PAFBC modes) with those from conventional BFBC (taller freeboard and recycle operation) and circulating fluidized bed combustion (CFBC) units is given in Table ES-1. The comparison is for typical high-volatile bituminous coals and sorbents of average reactivity. The values indicated for BFBC and CFBC were based on published information. The AFBC unit that was designed to act as a baseline for the comparison was indeed representative of the larger units even at the smaller scale for which it was designed. The PAFBC mode exhibited superior performance in relation to the AFBC mode. The higher combustion efficiency translates into reduced coal consumption and lower system operating cost; the improvement in sulfur capture implies less sorbent requirement and waste generation and in turn lower operating cost; lower NO{sub x} and CO emissions mean ease of site permitting; and greater steam-generation rate translates into less heat exchange surface area and reduced capital cost. Also, the PAFBC performance generally surpasses those of conventional BFBC, is comparable to CFBC in combustion and NO{sub x} emissions, and is better than CFBC in sulfur capture and CO emissions even at the scaled-down size used for the experimental feasibility tests.

Not Available

1989-11-01

16

Georgetown University's experience in the atmospheric fluidized bed combustor technology  

Microsoft Academic Search

An atmospheric fluidized bed combustor is the primary heat source for the Georgetown University steam supply. The combustor burns high sulfur coal with emissions that are environmentally acceptable. Attention is given to plant problems and modifications, including grid plate performance, the cinder trap reinjection process, the boiler bed antierosion baffles, the control system status, the flyash removal system, and the

D. J. Roy

1980-01-01

17

(Pulsed atmospheric fluidized bed combustion (PAFBC))  

SciTech Connect

This first Quarterly Technical Progress Report presents the results of work accomplished during the period April 19 through July 24,1988. The overall objective of the program is the development of a pulsed atmospheric fluidized-bed combustion (PAFBC) technology to burn coal and to provide heat and steam to commercial, institutional, and small industrial applications at a reasonable price in an environmentally acceptable manner. the program scope consisted of two tasks; the first was to establish preliminary feasibility by the use of theoretical and state-of-the-art information. This task was completed during the first quarter of the contract period and a topical report entitled, Pulsed Atmospheric Fluidized Bed combustion (PAFBC) - Preliminary Feasibility Study'' was prepared as a decision point to proceed'' deliverable in accordance with the terms of the contract. This first quarterly progress report therefore covers the contract activities subsequent to the approval of the feasibility study and the decision to proceed with the Task 2 effort. As the initial quarterly technical progress report, this document includes a subsection on background which will be omitted in subsequent reports. All effort during this period was devoted to the design and analysis of the PAFBC. Design drawings were prepared and fabrication and procurement initiated. Quotations were evaluated and a fabrication contract awarded. A site adjacent to the MTCI building was chosen for the installation of the PAFBC. Some ancillary components were purchased, renovated, and tested. Some delays in delivery of components have resulted in some schedule delay. It is anticipated that the program pace will accelerate as soon as parts are received and installation and assembly are initiated. 10 figs.,1 tab.

Not Available

1988-10-01

18

Atmospheric fluidized bed combustion advanced concept system  

SciTech Connect

DONLEE Technologies Inc. is developing with support of the US Department of Energy an advanced circulating fluidized bed technology known as the Vortex{trademark} Fluidized Bed Combustor (VFBC). The unique feature of the VFBC is the injection of a significant portion of the combustion air into the cyclone. Since as much as one-half of the total combustion air is injected into the cyclone, the cross-sectional area of the circulating fluidized bed is considerably smaller than typical circulating fluidized beds. The technology is being developed for two applications: Industrial-scale boilers ranging from 20,000 to 100,000 pounds per hour steam generating capacity; and two-stage combustion in which a substoichiometric Vortex Fluidized Bed Combustor (2VFBC) or precombustor is used to generate a combustible gas for use primarily in boiler retrofit applications. This Level II analysis of these two applications indicates that both have merit. An industrial-scale VFBC boiler (60,000 lb/hr of steam) is projected to be economically attractive with coal prices as high as $40 per ton and gas prices between $4 and $5 per thousand cubic feet. The payback time is between 3 and 4 years. The 2VFBC system was evaluated at three capacities of application: 20,000; 60,000 and 100,000 lb/hr of steam. The payback times for these three capacities are 4.5, 2.1 and 1.55 years, respectively. The 2VFBC has potential applications for retrofit of existing pulverized coal-fired boilers or as a new large (utility) boiler. Pressurized operation of the 2VFBC has considerable potential for combined cycle power generation applications. Experimental development of both applications is presented here to demonstrate the potential of these two technologies.

Not Available

1992-05-01

19

NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project  

SciTech Connect

The objective of this DOE Cooperative Agreement is to conduct a cost-shared clean coal technology project to demonstrate the feasibility of circulating fluidized bed combustion technology and to evaluate economic, environmental, and operational benefits of CFB steam generators on a utility scale. At the conclusion of the Phase 2 program, testing related to satisfying these objectives was completed. Data analysis and reporting are scheduled for completion by October 1991. (VC)

Not Available

1992-02-01

20

Steam generator with circulating atmospheric fluidized bed combustion  

NASA Astrophysics Data System (ADS)

The combustion of coal in power plants by conventional combustion techniques is studied with emphasis on combustion in a circulating atmospheric fluidized bed (CFBC). The CFBC method stays half way between the classical fluidized bed with a well defined bed height and the pneumatic transport where particles and fluidizing gas have the same velocity. The main advantages of CFBC are: flexibility with respect to coal types; easy elimination of 80% of sulfur by mixing the coal with calcium carbonate to a molecular ratio Ca/S of about two; reduced nitrogen oxides production due to the low combustion temperature of 900 C; high steam production efficiency with the combustion degree exceeding 99%; high overall efficiency with no further desulfurizing being needed; easy regulation; high heat transmission rates (350 to 400 W/m2K) reducing exchange surfaces; small boiler building; and the possibility to build in one module a 300 MW unit.

Wein, W.; Hoeffgen, H.; Maintok, K. H.; Daradimos, G.

1982-08-01

21

Pulsed atmospheric fluidized bed combustor apparatus and process  

DOEpatents

A pulsed atmospheric fluidized bed reactor system is disclosed and claimed along with a process for utilization of same for the combustion of, e.g. high sulfur content coal. The system affords a economical, ecologically acceptable alternative to oil and gas fired combustors. The apparatus may also be employed for endothermic reaction, combustion of waste products, e.g. organic and medical waste, drying, calcining and the like.

Mansour, Momtaz N. (Columbia, MD)

1992-01-01

22

Systems Study of Commercial Scale Atmospheric Fluidized-Bed Combustion with Appendices.  

National Technical Information Service (NTIS)

A preliminary investigation was performed to define the optimum technical and economic conditions for control of sulfur emissions in a system comprised of coal preparation, atmospheric fluidized-bed combustion (AFBC) and flue gas desulfurization. Using a ...

1979-01-01

23

Pulsed atmospheric fluidized bed combustion. Final report  

SciTech Connect

ThermoChem, under contract to the Department of Energy, conducted extensive research, development and demonstration work on a Pulsed Atmospheric Fluidized Bed Combustor (PAFBC) to confirm that advanced technology can meet these performance objectives. The ThermoChem/MTCI PAFBC system integrates a pulse combustor with an atmospheric bubbling-bed type fluidized bed combustor (BFBC) In this modular configuration, the pulse combustor burns the fuel fines (typically less than 30 sieve or 600 microns) and the fluidized bed combusts the coarse fuel particles. Since the ThermoChem/MTCI PAFBC employs both the pulse combustor and the AFBC technologies, it can handle the full-size range of coarse and fines. The oscillating flow field in the pulse combustor provides for high interphase and intraparticle mass transfer rates. Therefore, the fuel fines essentially burn under kinetic control. Due to the reasonably high temperature (>1093 C but less than the temperature for ash fusion to prevent slagging), combustion of fuel fines is substantially complete at the exit of the pulse combustor. The additional residence time of 1 to 2 seconds in the freeboard of the PAFBC unit then ensures high carbon conversion and, in turn, high combustion efficiency. A laboratory unit was successfully designed, constructed and tested for over 600 hours to confirm that the PAFBC technology could meet the performance objectives. Subsequently, a 50,000 lb/hr PAFBC demonstration steam boiler was designed, constructed and tested at Clemson University in Clemson, South Carolina. This Final Report presents the detailed results of this extensive and successful PAFBC research, development and demonstration project.

NONE

1998-03-01

24

Georgetown University atmospheric fluidized bed boiler cogeneration system  

SciTech Connect

This report presents the results of one year of operation of the cogeneration system capability of the Georgetown University coal- fired, atmospheric fluidized-bed (AFB) boiler. The AFB was designed and installed under a separate contract with the US Department of Energy. The AFB project funded by DOE to demonstrate that high sulfur coal could be burned in an environmentally acceptable manner in a urban environment such as Georgetown. In addition, operational data from the unit would assist the industry in moving directly into design and construction of commercially warranted industrial size AFB boilers. 9 figs., 3 tabs.

Podbielski, V.; Shaff, D.P.

1991-08-01

25

Atmospheric fluidized bed combustor development program. Final report  

SciTech Connect

The objective of this project was to demonstrate and promote the commercialization of a coal-fired atmospheric fluidized bed combustion (AFBC) system, with limestone addition for SO{sub 2} emissions control and a baghouse for particulate emissions control. This AFBC system was targeted for small scale industrial-commercial-institutional space and process heat applications in the 1 x 10{sup 6} to 10 x 10{sup 6} Btu/hr capacity range. A cost effective and environmentally acceptable AFBC technology in this size range would displace a considerable amount of gas/oil with coal while resulting in significant total cost savings to the owner/operators. The project itself was separated into three levels: (1) feasibility, (2--3) subsystem development and integration, and (4) proof-of-concept. In Level (1), the technical and economic feasibility of a 1 million Btu/hr coal-fired AFBC air heater was evaluated. In Level (2--3), the complete EER fluidized bed combustor (1.5 million Btu/hr) system was developed and tested. The goal or reducing SO{sub 2} emissions to 1.2 lb/10{sup 6} Btu, from high sulfur Ohio coal, was achieved by adding limestone with a Ca/S (coal) ratio of {approximately} 3.0. Finally, in Level (4), the proof-of-concept system, a 2.2 million Btu/hr unit was installed and successfully operated at Cedar Lane Farms, a commercial nursery in Ohio.

Ashworth, R.A.; Melick, T.A.; Plessinger, D.A.; Sommer, T.M. [Energy and Environmental Research Corp., Orville, OH (United States); Keener, H.M. [Ohio State Univ., Columbus, OH (United States). Ohio Agricultural Research and Development Center; Webner, R.L. [Will-Burt, Orrville, OH (United States)

1995-12-01

26

Development and applications of clean coal fluidized bed technology  

SciTech Connect

Power generation in Europe and elsewhere relies heavily on coal and coal-based fuels as the source of energy. The reliance will increase in the future due to the decreasing stability of price and security of oil supply. In other words, the studies on fluidized bed combustion systems, which is one of the clean coal technologies, will maintain its importance. The main objective of the present study is to introduce the development and the applications of the fluidized bed technology (FBT) and to review the fluidized bed combustion studies conducted in Turkey. The industrial applications of the fluidized bed technology in the country date back to the 1980s. Since then, the number of the fluidized bed boilers has increased. The majority of the installations are in the textile sector. In Turkey, there is also a circulating fluidized bed thermal power plant with a capacity of 2 x 160 MW under construction at Can in Canakkale. It is expected that the FBT has had, or will have, a significant and increasing role in dictating the energy strategies for Turkey.

Eskin, N.; Hepbasli, A. [Ege University, Izmir (Turkey). Faculty of Engineering

2006-09-15

27

Heat exchanger materials for fluidized-bed coal combustion  

Microsoft Academic Search

The objective of this study was to determine the corrosion performance of heat exchanger and uncooled internal structural materials in atmospheric fluidized-bed combustors (AFBCs). Although crushed limestone is used in the fluidized bed as a sulfur absorber, it is known that both oxidation and sulfidation of in-bed components occurs in beds that operate at temperatures of 500 to 870°C. Accordingly,

J. H. Devan; T. G. Godfrey; P. J. Ficalora

1981-01-01

28

MONITORING STRATEGIES FOR FLUIDIZED BED COMBUSTION COAL PLANTS  

EPA Science Inventory

Air and water monitoring strategies for commercial-size Fluidized Bed Combustion (FBC) coal plants are presented. This is one of five reports developing air and water monitoring strategies for advanced coal combustion (FBC), coal conversion (coal gasification and liquefaction), a...

29

Assessment of circulating atmospheric fluidized-bed combustion technology for utility applications  

Microsoft Academic Search

The primary objectives of this study was to develop a current evaluation of circulating atmospheric fluidized-bed combustion (AFBC) technology applied to a 200-MW boiler. This report presents process descriptions, drawings, and cost comparisons for 200-MW circulating AFBC and pulverized coal (PC) plants for four different coals. The circulating AFBC boil and immediate auxiliaries are based on technical and cost information

W. W. Hoskins; R. J. Keeth; P. R. Russell

1989-01-01

30

MATHEMATICAL MODEL FOR A FLUIDIZED-BED COAL GASIFIER  

EPA Science Inventory

The report gives results of gasifying four fuels--a devolatilized Kentucky bituminous coal, a New Mexico subbituminous coal, a North Carolina peat, and a Texas lignite--with steam and oxygen in a pilot-scale fluidized-bed reactor. Experimental results were used to provide an eval...

31

Mechanisms of coal-water mixture combustion in fluidized beds  

SciTech Connect

The first quarter of FY 1990 was used to correct problems described in the previous progress report and to initiate a series of experiments on calcination and sulfation of coal-water-limestone mixtures (CWLM) in fluidized beds. Results are discussed and compared to the burning of dry coal in a limestone bed. 10 refs., 5 figs.

Brown, R.C.

1989-01-01

32

Metallic species derived from fluidized bed coal combustion. [59 references  

SciTech Connect

Samples of fly ash generated by the combustion of Montana Rosebud coal in an experimental 18 inch fluidized bed combustor were collected. The use of a heated cascade impactor permitted collection of size fractionated material that avoided condensation of volatile gases on the particles. Elemental concentration trends were determined as a function of size and temperature and the results compared to published reports for conventional power plants. The behavior of trace metals appears to be substantially different in the two systems due to lower operating temperatures and the addition of limestone to the fluidized bed. Corrosion of the impactor plates was observed at the highest temperature and lowest limestone feed rate sampled during the study. Data from the elemental concentration and leaching studies suggest that corrosion is most likely due to reactions involving sodium sulfate. However, it is concluded that corrosion is less of a potential problem in fluidized-bed systems than in conventional coal-fired systems.

Natusch, D.F.S.; Taylor, D.R.

1980-01-01

33

Nucla circulating atmospheric fluidized bed demonstration project. Final report  

SciTech Connect

Colorado-Ute Electric Association began a study to evaluate options for upgrading and extending the life of its Nucla power station in 1982. Located in southwestern Colorado near the town of Nucla, this station was commissioned in 1959 with a local bituminous coal as its design fuel for three identical stoker-fired units, each rated at 12.6 MW(e). Poor station efficiency, high fuel costs, and spiraling boiler maintenance costs forced the Nucla Station into low priority in the CUEA dispatch order as early as 1981. Among the options CUEA considered was to serve as a host utility to demonstrate Atmospheric Fluidized Bed Combustion (AFBC) technology. The anticipated environmental benefits and apparent attractive economics of a circulating AFBC led to Colorado-Ute`s decision to proceed with the design and construction of a demonstration project in 1984 at the Nucla facility.

Not Available

1991-10-01

34

Nucla circulating atmospheric fluidized bed demonstration project  

SciTech Connect

During the fourth quarter of 1990, steady-state performance testing at the Nucla Circulating Fluidized Bed (CFB) resumed under sponsorship of the US Department of Energy. Co-sponsorship of the Demonstration Test Program by the Electric Power Research Institute (EPRI) was completed on June 15, 1990. From October through December, 1990, Colorado-Ute Electric Association (CUEA) completed a total of 23 steady-state performance tests, 4 dynamic tests, and set operating records during November and December as the result of improved unit operating reliability. Highlight events and achievements during this period of operation are presented.

Not Available

1991-01-31

35

Effect of Reaerosolized Fly Ash from an Atmospheric Fluidized Bed Combustor on Murine Alveolar Macrophages.  

National Technical Information Service (NTIS)

Male B6CF sub 1 mice were exposed to reaerosolized fly ash. The fly ash was collected from the final filter of an atmospheric pressure fluidized-bed coal combustor and reaerosolized from a liquid nitrogen suspension. In four short experiments, (30-36 hrs;...

P. C. Brennan F. R. Kirchner W. P. Norris

1979-01-01

36

Evaluation of alternative steam generator designs for Atmospheric Fluidized-Bed Combustion plants: Final report. [AFBC  

Microsoft Academic Search

The Atmospheric Fluidized Bed Combustion development program at the 20 MW pilot plant at TVA's Shawnee Station is addressing several design issues related to the scale-up requirements for utility application. These include use of overbed vs. underbed feed systems for coal, limestone, and recycled solids, load following and control design for reliable operation, and economies of scale. After initial screening

Dunlop

1987-01-01

37

Advanced fluidized bed technology applied to coals and other fuels  

SciTech Connect

This conference dealt with a variety of subjects of interest to industrial users of coal. The eleven papers covered fluidized bed combustion of coal and solid, liquid, and gaseous wastes; coal purchasing and specifications; industrial fuel substitution of coal; combined-cycle power plants; corrosion protection of heat exchangers; operating costs of coal-fired systems; technical services available for boiler maintenance; training of personnel to work with coal and coal systems; refuse-fueled power plants firing coal and municipal wastes; chemical feedstock production using coal gasification; and waste product utilization of tailings from coal preparation plants. All the papers were abstracted separately. 79 references, 56 figures, 34 tables. (CKK)

Litt, R.D.; Sirois, R.H. (eds.)

1983-01-01

38

Atmospheric fluidized-bed combustion fabric filter monitoring  

Microsoft Academic Search

In recent years atmospheric fluidized bed combustion (AFBC) has become a commercially accepted technology for solid-fuel-fired power generation systems. As part of their research efforts to support the development of particulate control technology for the utility industry, EPRI has evaluated the performance of electrostatic precipitators and fabric filters downstream of AFBC boilers. EPRI has recently completed studies of fabric filtration

Cushing

1992-01-01

39

Atmospheric fluidized bed combustion advanced concept system. Final report  

SciTech Connect

DONLEE Technologies Inc. is developing with support of the US Department of Energy an advanced circulating fluidized bed technology known as the Vortex{trademark} Fluidized Bed Combustor (VFBC). The unique feature of the VFBC is the injection of a significant portion of the combustion air into the cyclone. Since as much as one-half of the total combustion air is injected into the cyclone, the cross-sectional area of the circulating fluidized bed is considerably smaller than typical circulating fluidized beds. The technology is being developed for two applications: Industrial-scale boilers ranging from 20,000 to 100,000 pounds per hour steam generating capacity; and two-stage combustion in which a substoichiometric Vortex Fluidized Bed Combustor (2VFBC) or precombustor is used to generate a combustible gas for use primarily in boiler retrofit applications. This Level II analysis of these two applications indicates that both have merit. An industrial-scale VFBC boiler (60,000 lb/hr of steam) is projected to be economically attractive with coal prices as high as $40 per ton and gas prices between $4 and $5 per thousand cubic feet. The payback time is between 3 and 4 years. The 2VFBC system was evaluated at three capacities of application: 20,000; 60,000 and 100,000 lb/hr of steam. The payback times for these three capacities are 4.5, 2.1 and 1.55 years, respectively. The 2VFBC has potential applications for retrofit of existing pulverized coal-fired boilers or as a new large (utility) boiler. Pressurized operation of the 2VFBC has considerable potential for combined cycle power generation applications. Experimental development of both applications is presented here to demonstrate the potential of these two technologies.

Not Available

1992-05-01

40

Fluidized bed combustor and coal gun-tube assembly therefor  

DOEpatents

A coal supply gun assembly for a fluidized bed combustor which includes heat exchange elements extending above the bed's distributor plate assembly and in which the gun's nozzles are disposed relative to the heat exchange elements to only discharge granular coal material between adjacent heat exchange elements and in a path which is substantially equidistant from adjacent heat exchange elements.

Hosek, William S. (Mt. Tabor, NJ); Garruto, Edward J. (Wayne, NJ)

1984-01-01

41

Fluidized-bed bioreactor process for the microbial solubiliztion of coal  

DOEpatents

A fluidized-bed bioreactor system for the conversion of coal into microbially solubilized coal products. The fluidized-bed bioreactor continuously or periodically receives coal and bio-reactants and provides for the production of microbially solubilized coal products in an economical and efficient manner. An oxidation pretreatment process for rendering coal uniformly and more readily susceptible to microbial solubilization may be employed with the fluidized-bed bioreactor.

Scott, Charles D. (Oak Ridge, TN); Strandberg, Gerald W. (Farragut, TN)

1989-01-01

42

Fluidized-bed bioreactor system for the microbial solubilization of coal  

DOEpatents

A fluidized-bed bioreactor system for the conversion of coal into microbially solubilized coal products. The fluidized-bed bioreactor continuously or periodically receives coal and bio-reactants and provides for the production of microbially solubilized coal products in an economical and efficient manner. An oxidation pretreatment process for rendering coal uniformly and more readily susceptible to microbial solubilization may be employed with the fluidized-bed bioreactor. 2 figs.

Scott, C.D.; Strandberg, G.W.

1987-09-14

43

NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project. 1990 Annual report  

SciTech Connect

The objective of this DOE Cooperative Agreement is to conduct a cost-shared clean coal technology project to demonstrate the feasibility of circulating fluidized bed combustion technology and to evaluate economic, environmental, and operational benefits of CFB steam generators on a utility scale. At the conclusion of the Phase 2 program, testing related to satisfying these objectives was completed. Data analysis and reporting are scheduled for completion by October 1991. (VC)

Not Available

1992-02-01

44

Characterization of fuels for atmospheric fluidized bed combustion  

SciTech Connect

The Electric Power Research Institute (EPRI) has sponsored a fuels characterization program for the past several years with the intention of assisting utilities and boiler manufacturers in evaluating fuel quality impact on atmospheric fluidized bed combustion (AFBC) performance. The goal has been to provide an improved framework for making fuel switching decisions and consolidating operating experience. Results from this program include a set of bench-scale testing procedures, a fuel characterization data base, and a performance simulation model that links fuel characteristics to combustion performance. This paper reviews the major results of the fuels characterization program. The testing procedures, data base, and performance simulation models are briefly described and their application illustrated with examples. Performance predictions for the B W 1-ft{sup 2} bench-scale AFBC and the Tennessee Valley Authority (TVA) 20 MW(e) AFBC Pilot Plant are compared with actual test data. The relationship of coal rank to combustion is discussed. 11 refs., 12 figs., 5 tabs.

Daw, C.S. (Oak Ridge National Lab., TN (USA)); Rowley, D.R.; Perna, M.A. (Babcock and Wilcox Co., Alliance, OH (USA). Research Center); Stallings, J.W. (Electric Power Research Inst., Palo Alto, CA (USA)); Divilio, R.J. (Combustion Systems, Inc., Silver Spring, MD (USA))

1990-01-01

45

Effect of reaerosolized fly ash from an atmospheric fluidized bed combustor on murine alveolar macrophages  

Microsoft Academic Search

Male B6CF⁠mice were exposed to reaerosolized fly ash. The fly ash was collected from the final filter of an atmospheric pressure fluidized-bed coal combustor and reaerosolized from a liquid nitrogen suspension. In four short experiments, (30-36 hrs; 6 hrs\\/day for 5-6 days) the fly ash was a composite of both start-up and steady-state material. In another experiment of longer

P. C. Brennan; F. R. Kirchner; W. P. Norris

1979-01-01

46

Gas turbine engine power plant with a coal burning fluidized bed  

Microsoft Academic Search

A gas turbine engine power plant having a coal burning fluidized bed utilized as the heating source for the power plant is described. The fluidized bed comprises inerts and coal in which is immersed a temperature sensitive device, the signal from which is used to control the supply of coal to the bed to maintain the bed at a predetermined

Jubb

1978-01-01

47

Heat exchanger fouling in a coal-fired fluidized bed combustor  

Microsoft Academic Search

Operating experience with fouling of a finned tube flue gas heat exchanger is described. The heat exchanger is located in the convection pass of an industrial type, pilot-sized coal-fired atmospheric fluidized bed combustor using a forced circulation water\\/glycol coolant loop. Values of heat transfer coefficient were calculated from actual run data, and compared with design values. It was found that

H. M. Stanton; S. Adibhatla; R. D. Cunningham

1983-01-01

48

Modeling and analysis of coal combustion in two-stage circulating fluidized bed combustor  

SciTech Connect

The development of Circulating Atmospheric Fluidized Bed Combustion (CFBC) has grown rapidly during the past few years. CFBC's are complex chemical reactors in which coal combustion, sulfur capture, and nitrogen oxide (NO/sub chi/) formation and destruction take place. Two-stage Circulating Fluidized Bed Combustors are innovative designs in which the handling and feeding of coal and limestone are performed separately to develop a more efficient CFBC with reduced NO/sub chi/ and SO/sub chi/ emissions, better thermal efficiency and reduced sorbent consumption. To verify the flow field part of the model, a two-stage Plexiglas reactor has been designed and constructed for flow visualization study. The bench scale two-stage CFB design has incorporated the continuous measurements of pressure at various heights. Comparison of theoretical predictions and measured data is presented and discussed.

Ettouney, H.M. (Kuwait Univ. (Kuwait).); Farag, I.H. (New Hampshire Univ., Durham, NH (USA))

1988-01-01

49

Pressurized fluidized bed combustor and coal gun construction therefor  

SciTech Connect

A pressurized, fluidized bed combustor is disclosed. It includes a housing having a combustor chamber therein with a distributor plate closing the lower portion of the housing and arranged above a fluidizer windbox, which, in turn, is arranged above a heat exchanger inlet plenum which is mounted above a bottom of the combustor. A coal gun is provided for discharging coal into the fluidized bed, and it comprises an outer guide tube which extends from a spaced location above the distributor plate downwardly through the bottom of the combustor chamber and it includes a portion which extends exteriorly of the combustor chamber. This exterior portion carries a ball valve which has a passage therethrough which makes it possible to insert a coal supply pipe upwardly in the interior of the outer guide pipe and through the passage of the ball valve up to substantially the top of the outer pipe at a location above the distributor plate within the reaction bed. For withdrawing the coal supply pipe, it is possible to remove the pipe downwardly through the ball valve until the top end thereof is located directly below the ball valve but still within the outer diameter pipe and located within a stuffing box thereof. At such location, then the ball valve is closed and the ball supply pipe may be withdrawn all the way without reducing the pressure in the reactor.

Hosek, W.S.

1981-09-29

50

Experience with atmospheric fluidized bed gasification of switchgrass  

SciTech Connect

Switchgrass was gasified in a bubbling fluidized bed reactor rated at 800 kW (2.75 MMBtu/hr) thermal input and operating at atmospheric pressure. A combustible gas with higher heating value varying between 4.2--5.9 MJ/Nm{sup 3} (114--160 Btu/scf) was produced. Carbon conversion was approximately 85%. Difficulties in feeding high moisture switchgrass inhibited smooth reactor operation. Several feed systems for switchgrass were tried with varying degrees of success. The results of gasification trials using switchgrass as fuel are described.

Smeenk, J.; Brown, R.C. [Iowa State Univ., Ames, IA (United States). Center for Coal and the Environment

1998-12-31

51

Air Dense Medium Fluidized Bed for Dry Beneficiation of Coal : Technological Challenges for Future  

Microsoft Academic Search

Air Dense Medium Fluidized Bed (ADMFB) offers a better alternative approach for dry coal beneficiation. In recent years, there has been a rapid advancement in the understanding of fluidized bed behavior and a great deal of work has also been done to make this process competitive with conventional wet beneficiation processes. At the same time, numbers of information available in

S. Mohanta; C. S. Rao; A. B. Daram; S. Chakraborty; B. C. Meikap

2012-01-01

52

Testing of Illinois coal in a circulating fluidized bed  

SciTech Connect

Illinois No. 6 mine-run coal, washed coal, and coal-cleaning waste by-products from a Murdock, Illinois, mine were tested in a 30-foot-tall, small-scale (1 million-Btu/hr), circulating, fluidized-bed combustor (CFBC) located at the Babcock Wilcox Alliance (B W) (Ohio) Research Center. The goal of the project was to promote the use of Illinois coal by demonstrating that the three fuels could be combusted efficiently and in an environmentally acceptable manner. The ability to burn mine-run coal could justify eliminating the coal-cleaning step for new CFBC units. A positive demonstration with the cleaning-waste by-products would reduce the cost for fuel for all users of Illinois washed coal by reducing waste disposal costs. In addition, the existing stockpiles of coal wastes could be removed. The project was co-funded by the Illinois Center for Research on Sulfur in Coal, the Electric Power Research Institute (EPRI), and B W. The combustion efficiencies of all three fuels were similar to efficiencies obtained with other bituminous coals tested on the unit. All three fuels could be combusted with acceptable CO, SO{sub 2}, and NO{sub x} emissions. The agglomeration that occurred with the mine-run coal was alleviated by increasing the bed drain rate and utilizing periodic bed dumps to remove small agglomerates. 7 figs., 7 tabs.

Flynn, T.J.; Hooper, M.P.; Ilan, R. (Babcock and Wilcox Co., Alliance, OH (USA). Research Center)

1990-01-01

53

Adding coal-fired fluidized bed combustion to gas and oil boilers  

SciTech Connect

Fluidized bed combustion is an economically attractive, technically feasible approach for burning all grades of coal without creating pollution problems. Robinson discusses the combustion and emission control operations of a fluidized bed combustor, explains the component changes necessary to the water/steam and air/flue gas subsystems, and describes the new ash removal and coal and limestone feed subsystems needed to retrofit the equipment to the plant's existing gas or oil-fired boiler.

Robinson, T.F.

1986-07-01

54

Atmospheric fluidized-bed combustion waste management design guidelines: Final report  

SciTech Connect

Atmospheric Fluidized Bed Combustion (AFBC) is a commercially available and applied coal combustion technology used to control SO2 emissions. This process is rapidly gaining utility acceptance. Because physical and chemical properties of wastes generated by fluidized bed combustors differ from those of conventional coal combustion by-products (fly ash and scrubber sludge), typical waste management practices may need to be altered. This report presents technical guidelines for designing and operating the waste management system of an AFBC facility equipped to burn coal. Waste transfer, storage, pretreatment/conditioning, transport, and disposal are addressed. These guidelines are based on current AFBC waste management practices and associated operating problems as well as critical waste properties (e.g., chemical constituents, gradation, density, moisture content, flowability, strength, leachate properties, etc.). Consequently, the report briefly describes the waste management practices of four existing or planned utility installations and four industrial facilities using bituminous coal as their primary fuel source. Results of waste property tests conducted as part of this study, and test data from other studies are reported and compared. Conceptual designs of both new and retrofit AFBC waste management systems are presented to demonstrate the economic impact of AFBC on waste management. Parametric cost sensitivity analyses illustrate the impact of significant design parameters on waste management costs. 111 refs., 81 figs., 58 tabs.

Lees, M.G.; Napoli, K.G.; Saylor, D.K.; Stewart, M.M.

1988-12-01

55

Pulsed atmospheric fluidized bed combustion. Quarterly report, January--March 1996.  

National Technical Information Service (NTIS)

Progress is reported on the design of an atmospheric fluidized-bed combustor. Tasks described include: the mechanical design, civil and structural design; electrical design; and controls and instrumentation.

1997-01-01

56

Atmospheric fluidized bed combustion for small scale market sectors. Final report  

SciTech Connect

The objective of this project was to demonstrate and promote the commercialization of coal-fired atmospheric fluidized bed combustion (AFBC) systems, with limestone addition for SO{sub 2} emissions control and a baghouse for particulate emissions control. This AFBC system was targeted for small scale industrial-commercial-institutional space and process heat applications. A cost effective and environmentally acceptable AFBC technology in this size range would displace a considerable amount of gas/oil with coal while resulting in significant total cost savings to the owner/operators. In the Proof-of-Concept Phase, a 2.2 x 10{sup 6} Btu/hr unit was installed and successfully operated at Cedar Lane Farms (CLF), a commercial nursery in Ohio. The heat from the fluidized bed was used to heat hot water which was recirculated through greenhouses for cool weather heating. The system was designed to be fully automated with minimal operator attention required. The AFBC system installed at CLF was an improved design that incorporated flyash/sorbent reinjection and an underbed feed system to improve limestone utilization. With these additions it was possible to lower the Ca/S ratio from {approximately} 3.0 to 2.0, and still maintain an SO{sub 2} emissions level of 1.2 lb/10{sup 6} Btu when burning the same high sulfur Ohio coal tested at OARDC.

Ashworth, R.A.; Plessinger, D.A.; Sommer, T.M. [Energy and Environmental Research Corp., Orville, OH (United States); Keener, H.M. [Ohio Agricultural Research and Development Center, OH (United States); Webner, R.L. [Will-Burt Co., Orrville, OH (United States)

1997-03-31

57

Commercialization potential of AFBC (atmospheric fluidized bed combustion) concrete  

SciTech Connect

A study has been conducted of the mechanistic basis for cementing action, strength development and stability of no-cement'' concretes containing, as binders, only fluidized bed combustion (FBC) by-products and pulverized fuel ash (PFA) with no Portland cement. The FBC and PFA raw materials were selected to cover a wide range of potential compositions. The main reactive phases in the binders are calcium oxide/hydroxide, anhydrite and dehydroxylated clays from the FBC residues; and aluminosilicate glass from the PFA. The proportions of the reactive calcium phases to coal-associated mineral phases ranged from 2:1 to 1:5 for the different FBC sources. Possible applications for the binder include high volume applications -- such as production of blocks for undersea reef construction and underground mine support, mine backfill, soil cement, expansive grout, and waste stabilization in co-disposal with other waste forms -- where slow setting and expansion may not be a problem. 119 refs., 38 figs., 15 tabs.

Berry, E.E.; Hemmings, R.T.; Cornelius, B.J. (MATEX Consultants, Inc., Mississauga, ON (Canada))

1991-01-01

58

Combustion of Coal Char Particles under Fluidized Bed Oxyfiring Conditions  

NASA Astrophysics Data System (ADS)

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.

Scala, Fabrizio; Chirone, Riccardo

59

Release of nitrogen precursors from coal and biomass residues in a bubbling fluidized bed  

SciTech Connect

This work was undertaken with the aim of quantifying the relative amounts of NH{sub 3} and HCN released from different residues during their devolatilization under fluidized bed conditions. The results were compared with data collected for bituminous coals of different origin. The relation between amounts of HCN and NH{sub 3} released and the levels of NOX and N{sub 2}O formed during cocombustion was also addressed. The partitioning of nitrogen between volatiles and char was also quantified. The pyrolysis studies were undertaken in a small fluidized bed reactor of 80 mm of ID and 500 mm high using an inert atmosphere (N{sub 2}). The HCN and NH{sub 3} were quantified by bubbling the pyrolysis gases in absorbing solutions which were subsequently analyzed with selective electrodes. The combustion studies were carried out on a pilot installation. The fluidized bed combustor is square in cross section with each side being 300 mm long. There is secondary air supply to the freeboard at different heights to deal with high volatile fuels as almost all waste materials are. The temperatures in the bed and in the freeboard and that of the flue gases leaving the reactor were continuously monitored. The results obtained suggest that, while coal releases nitrogen mostly as HCN, residues like RDF and sewage sludge give out fuel-N in greater quantities as NH{sub 3}. Residues at fluidized bed combustion (FBC) temperatures release more than 80% of the fuel-N with the volatiles. The NH{sub 3} evolved during pyrolysis acted as a reducing agent on NOX emissions. The presence of calcium significantly reduces the emission of N{sub 2}O probably by interfering with HCN chemistry. With high amounts of residues in the fuel mixture, the relative importance of char on the nitrogen chemistry substantially decreases. By using cocombustion, it is possible to reduce fuel-N conversion to NOX and N{sub 2}O, by tuning the amounts of coal and residue in the mixture. 29 refs., 18 figs., 3 tabs.

P. Abelha; I. Gulyurtlu; I. Cabrita [Instituto Nacional de Engenharia, Lisbon (Portugal)

2008-01-15

60

Co-combustion of agricultural residues with coal in a fluidized bed combustor.  

PubMed

Power generation from biomass is an attractive technology that utilizes agricultural residual waste. In order to explain the behavior of biomass-fired fluidized bed incinerator, biomass sources from agricultural residues (rice husk and palm kernel) were co-fired with coal in a 0.15m diameter and 2.3m high fluidized bed combustor. The combustion efficiency and carbon monoxide emissions were studied and compared with those for pure coal combustion. Co-combustion of a mixture of biomass with coal in a fluidized bed combustor designed for coal combustion increased combustion efficiency up to 20% depending upon excess air levels. Observed carbon monoxide levels fluctuated between 200 and 900 ppm with the addition of coal. It is evident from this research that efficient co-firing of biomass with coal can be achieved with minimal modifications to existing coal-fired boilers. PMID:18614348

Ghani, W A W A K; Alias, A B; Savory, R M; Cliffe, K R

2008-07-09

61

Ash vaporization in circulating fluidized bed coal combustion  

SciTech Connect

In this work, the vaporization of the ash-forming constituents in circulating fluidized bed combustion (CFBC) in a full-scale 80 MW{sub th} unit was studied. Ash vaporization in CFBC was studied by measuring the fly ash aerosols in a full-scale boiler upstream of the electrostatic precipitator (ESP) at the flue gas temperature of 125{degree}C. The fly ash number size distributions showed two distinct modes in the submicrometer size range, at particle diameters 0.02 and 0.3 {mu}m. The concentration of the ultrafine 0.02-{mu}m mode showed a large variation with time and it decreased as the measurements advanced. The concentration of the 0.02-{mu}m mode was two orders of magnitude lower than in the submicrometer mode observed earlier in the bubbling FBC and up to three orders of magnitude lower than in the pulverized coal combustion. Scanning electron micrographs showed few ultrafine particles. The intermediate mode at 0.3 {mu}m consisted of particles irregular in shape, and hence in this mode the particles had not been formed via a gas to particle route. We propose that the 0.3-{mu}m mode had been formed from the partial melting of the very fine mineral particles in the coal. The mass size distribution in the size range 0.01-70 {mu}m was unimodal with maximum at 20 {mu}m. Less than 1% of the fly ash particles was found in the submicrometer size range. 35 refs., 8 figs., 3 tabs.

Lind, T.; Kauppinen, E.I.; Maenhaut, W. [Univ. of Gent (Belgium); Shah, A.; Huggins, F. [Univ. of Kentucky, Lexington, KY (United States)

1996-04-01

62

Scale-up of circulating fluidized bed coal combustors  

SciTech Connect

This experimental project has been aimed at quantifying the effects of scale-up upon the hydrodynamics of Circulating Fluidized Bed (CFB) coal combustors. We have have constructed a cold CFB facility with the ability to recirculate-rather than discard-fluidization gas mixtures of adjustable density and viscosity. Hydrodynamic analogy between the cold bed and a coal combustor is achieved by matching all relevant dimensionless parameters. Several choices of gas composition and particle properties make the cold flow analogous to that in combustors of diameters in the range 0.3 to 1m. Therefore, for the first time, scale-up effects are quantified directly using a single cold flow facility. During the previous reporting period, we carried out the first two phases of the scale -up experiments i.e., the fluidization of glass beads and plastic pellets using mixtures of helium and carbon dioxide. This quarter, we have completed the third phase of the scale-up experiments using iron flakes. By fluidizing two glass powders of identical characteristics but largely different surface friction coefficients, we have discovered that particle friction affects the flow. Effort has also been on modeling particle interaction in gas-solid flows using elements of rapid granular flow. Because detailed measurements of velocity fluctuations are not yet available in dense flows, we have first considered dilute, turbulent flows of relatively massive particles. Finally, we have/studied the heat transfer from a suspension of massive particles of low Biot number transported in a vertical pipe. 9 refs., 2 figs., 1 tab.

Louge, M.Y.

1990-01-01

63

Supportive Studies in Fluidized-Bed Combustion.  

National Technical Information Service (NTIS)

The report gives results of studies supporting the development of atmospheric and pressurized fluidized-bed combustion (FBC) of coal. It includes laboratory and bench-scale studies to provide needed information on combustion optimization, regeneration pro...

A. Jonke G. Vogel I. Johnson S. Lee J. Lenc

1977-01-01

64

Steam gasification of coal at low-medium (600-800{sup o}C) temperature with simultaneous CO{sub 2} capture in a bubbling fluidized bed at atmospheric pressure. 2. Results and recommendations for scaling up  

SciTech Connect

A gasification gas with an H{sub 2} content as high as 80 vol %, dry basis has been obtained by gasification of coal with pure steam at 600-800{sup o}C. The gasifier used was an atmospheric and bubbling fluidized bed operating with CaO in the bed as the CO{sub 2} sorbent. The research was carried out at a small pilot plant scale with continuous feeding of coal and batch mode introduction of the CaO. The gas composition and gas quality (tar content) is given for the following variables of operation: (a) type of in-bed sorbent used, (b) the amount of CaO in the bed related to the amount of coal fed, (c) temperature in the gasifier bed, (d) weight hourly space velocity (h{sup -1}) of the coal in the gasifier, and (e) time(-on-stream). To capture CaO at atmospheric pressure, the gasification with in-bed CaO had to be carried out at low-medium (600-800{sup o}C) gasification temperatures. For this reason, the tar content in the gasification gas was high (up to 52 g/Nm{sup 3}), which lowered the value of the H{sub 2}-rich gasification raw gas. It is demonstrated that a gas rich in H{sub 2} (80 vol % H{sub 2}, dry basis), and with very low CO{sub 2} and tar contents, can be obtained only if the coal gasification, at atmospheric pressure and with pure steam, is carried out at (CaO/coal) ratios above 10-15.

Corella, J.; Toledo, J.M.; Molina, G. [Universidad Complutense de Madrid, Madrid (Spain). Dept. of Chemical Engineering

2008-03-19

65

JV Task 108 - Circulating Fluidized-Bed Combustion and Combustion Testing of Turkish Tufanbeyli Coal  

Microsoft Academic Search

Two combustion tests were performed at the Energy & Environmental Research Center (EERC) using Tufanbeyli coal from Turkey. The tests were performed in a circulating fluidized-bed combustor (CFBC) and a pulverized coal-fired furnace, referred to as the combustion test facility (CTF). One of the goals of the project was to determine the type of furnace best suited to this coal.

Douglas Hajicek; Jay Gunderson; Ann Henderson; Stephen Sollom; Joshua Stanislowski

2007-01-01

66

Direct Reduction of Hematite Fines with Coal in a Fluidized Bed.  

National Technical Information Service (NTIS)

A preliminary investigation was undertaken on the direct reduction of hematite fines in a single-stage fixed fluidized bed. Coal was combusted in situ as a means of supplying the heat and producing the reducing gas. It was found that the type of coal used...

J. C. van den Berg R. J. Dippenaar

1986-01-01

67

Preliminary report on corrosion analysis of heat exchanger tubes from a fluidized-bed coal combustor. [2 references  

Microsoft Academic Search

The Energy Division of ORNL is planning the construction of a fluidized-bed coal combustor pilot plant. In order to gain preliminary materials compatibility information, a small scale MIUS fluidized bed was constructed, and a testing program of candidate heat exchanger tube materials was initiated. Candidate materials included Incoloy 800, Inconel 600, type 304 and 316 stainless steel, and aluminized Incoloy

R. H. Cooper; J. H. DeVan

1977-01-01

68

Atmospheric fluidized bed combustion technology test unit for industrial cogeneration plants  

Microsoft Academic Search

The AFBC Technology Test Unit Program will develop the technology for a fluidized bed coal combustion system to provide a source of high temperature air for process heating and power generation with gas turbines in industrial plants. The gas turbine has the advantages of a higher ratio of electric power output to exhaust heat load and a higher exhaust temperature

A. P. Fraas; R. S. Holcomb

1977-01-01

69

PRELIMINARY ENVIRONMENTAL ASSESSMENT OF COAL-FIRED FLUIDIZED-BED COMBUSTION SYSTEMS  

EPA Science Inventory

The report evaluates potential pollutants which could be generated in coal-fired fluidized-bed combustion (FBC) processes. The primary emphasis is on organic compounds, trace elements, inorganic compounds (other than SO2 and Nox), and particulates. Using available bench scale or ...

70

Ecotoxicological Assessment of Ashes and Particulate Matter from Fluidized Bed Combustion of Coal  

Microsoft Academic Search

Toxicity of ash and particulate matter from the gases generated in coal fluidized bed combustion (FBC) has been determined by the Microtox assay according to the standard leachate procedure. Results are compared with the polycylic aromatic hydrocarbon (PAH) content of the particulate matter, which was determined by fluorescence spectroscopy. Although PAHs are considered highly toxic compounds, the low ecotoxicity values

M. Callén; E. Marañón; A. Mastral; R. Murillo; P. Salgado

1998-01-01

71

Experiments on heat exchanger solidity for coal-fired fluidized bed applications  

Microsoft Academic Search

The efficient extraction of a high-temperature working fluid from a coal-fired fluidized bed combustor depends, to a great extent, on the design of the immersed heat exchanger. Of special importance is the solidity of the cooling tubes immersed in the bed. The interaction between increasing solidity and the consequent degradation of proper fluidization and circulation is being studied at the

G. Miller; V. Zakkay

1980-01-01

72

The optimization of heat exchanger solidity for coal-fired fluidized bed combustors  

Microsoft Academic Search

The efficient extraction of a high-temperature working fluid from a coal-fired fluidized bed combustor depends, to a great extent, on the design of the immersed heat exchanger. Of special importance is the solidity of the cooling tubes immersed in the bed. The interaction between increasing solidity and the consequent degradation of proper fluidization and circulation is being studied at the

G. Miller; V. Zakkay; S. Rosen

1979-01-01

73

ENVIRONMENTAL ASSESSMENT OF THE FLUIDIZED-BED COMBUSTION OF COAL: METHODOLOGY AND INITIAL RESULTS  

EPA Science Inventory

The paper discusses a program being conducted by the U.S. Environmental Protection Agency (EPA), aimed at complete environmental assessment (EA) of the fluidized-bed combustion (FBC) of coal. It reviews the EA methodology being developed by EPA: identification of current technolo...

74

CERAMIC FILTER TESTS AT THE EPA/EXXON PFBC (PRESSURIZED FLUIDIZED BED COAL COMBUSTION) MINIPLANT  

EPA Science Inventory

The paper describes the performance of the Acurex ceramic bag filter operating at temperatures up to 880C and pressures up to 930 kPa on particulate-laden flue gas from a pressurized fluidized-bed coal combustion (PFBC) unit on a slipstream of gas taken after the second stage cyc...

75

DOE Cost Comparison Study: Industrial Fluidized Bed Combustion Vs Conventional Coal Technology.  

National Technical Information Service (NTIS)

This study compares the capital and operating costs of two different industrial boiler technologies, each producing 250,000 lbs steam/hr: Fluidized Bed Combustion (FBC) and Pulverized Coal (PC) combustion used in conjunction with a limestone Flue Gas Desu...

D. T. Myrick

1980-01-01

76

[Pulsed atmospheric fluidized bed combustion (PAFBC)]. Technical progress report, May--July 1988  

SciTech Connect

This first Quarterly Technical Progress Report presents the results of work accomplished during the period April 19 through July 24,1988. The overall objective of the program is the development of a pulsed atmospheric fluidized-bed combustion (PAFBC) technology to burn coal and to provide heat and steam to commercial, institutional, and small industrial applications at a reasonable price in an environmentally acceptable manner. the program scope consisted of two tasks; the first was to establish preliminary feasibility by the use of theoretical and state-of-the-art information. This task was completed during the first quarter of the contract period and a topical report entitled, ``Pulsed Atmospheric Fluidized Bed combustion (PAFBC) - Preliminary Feasibility Study`` was prepared as a ``decision point to proceed`` deliverable in accordance with the terms of the contract. This first quarterly progress report therefore covers the contract activities subsequent to the approval of the feasibility study and the decision to proceed with the Task 2 effort. As the initial quarterly technical progress report, this document includes a subsection on background which will be omitted in subsequent reports. All effort during this period was devoted to the design and analysis of the PAFBC. Design drawings were prepared and fabrication and procurement initiated. Quotations were evaluated and a fabrication contract awarded. A site adjacent to the MTCI building was chosen for the installation of the PAFBC. Some ancillary components were purchased, renovated, and tested. Some delays in delivery of components have resulted in some schedule delay. It is anticipated that the program pace will accelerate as soon as parts are received and installation and assembly are initiated. 10 figs.,1 tab.

Not Available

1988-10-01

77

Predicting N sub 2 O emissions from circulating fluidized-bed coal combustion  

SciTech Connect

A parametric pilot-scale investigation of three low- and two high-rank coals has shown that temperature and coal type are the dominant parameters influencing nitrous oxide (N{sub 2}0) emissions. Excess air, limestone feed rate, and air split have a minor impact on N{sub 2}0 emissions. A model to predict N{sub 2}0 emissions has been developed and will be refined with further experimentation. Typically, N{sub 2}0 measured emissions from atmospheric FBCs can range from 40 to 200 ppM, depending on the coal properties and operational and design parameters. In contrast, pulverized coal-fired boilers emit very low levels (0-10 ppM) of N{sub 2}0. The purpose of this paper to report the effect of key operating parameters, the relative importance of coal type, and the potentially significant coal properties for producing N{sub 2}0 emissions in a circulating fluidized-bed combustor (CFBC). The generation of N{sub 2}0 emissions is quantified in an empirical model based on the experimental data.

Mann, M.D.; Collings, M.E.; Young, B.C. (North Dakota Univ., Grand Forks, ND (United States). Energy and Environmental Research Center); Botros, P.E. (USDOE Morgantown Energy Technology Center, WV (United States))

1992-01-01

78

Predicting N{sub 2}O emissions from circulating fluidized-bed coal combustion  

SciTech Connect

A parametric pilot-scale investigation of three low- and two high-rank coals has shown that temperature and coal type are the dominant parameters influencing nitrous oxide (N{sub 2}0) emissions. Excess air, limestone feed rate, and air split have a minor impact on N{sub 2}0 emissions. A model to predict N{sub 2}0 emissions has been developed and will be refined with further experimentation. Typically, N{sub 2}0 measured emissions from atmospheric FBCs can range from 40 to 200 ppM, depending on the coal properties and operational and design parameters. In contrast, pulverized coal-fired boilers emit very low levels (0-10 ppM) of N{sub 2}0. The purpose of this paper to report the effect of key operating parameters, the relative importance of coal type, and the potentially significant coal properties for producing N{sub 2}0 emissions in a circulating fluidized-bed combustor (CFBC). The generation of N{sub 2}0 emissions is quantified in an empirical model based on the experimental data.

Mann, M.D.; Collings, M.E.; Young, B.C. [North Dakota Univ., Grand Forks, ND (United States). Energy and Environmental Research Center; Botros, P.E. [USDOE Morgantown Energy Technology Center, WV (United States)

1992-09-01

79

Computer Simulation of Atmospheric Freeze Drying of Carrot Slices in a Fluidized Bed  

Microsoft Academic Search

Nam and Song's model, which describes the first stage of vacuum freeze drying, is adapted to atmospheric pressure conditions in a pulsating fluidized bed, discretizing the differential equations by finite-difference according to the implicit scheme. The generated algebraic systems of equations are solved by the tridiagonal matrix algorithm (TDMA). The effect of the variable time step on computation time is

V. Bubnovich; E. Quijada; A. Reyes

2009-01-01

80

Development of an advanced process for drying fine coal in an inclined fluidized bed  

SciTech Connect

The objective of this research project was to demonstrate a technically feasible and economically viable process for drying and stabilizing high-moisture subbituminous coal. Controlled thermal drying of coal fines was achieved using the inclined fluidized-bed drying and stabilization process developed by the Western Research Institute. The project scope of work required completion of five tasks: (1) project planning, (2) characterization of two feed coals, (3) bench-scale inclined fluidized-bed drying studies, (4) product characterization and testing, and (5) technical and economic evaluation of the process. High moisture subbituminous coals from AMAX Eagle Butte mine located in the Powder River Basin of Wyoming and from Usibelli Coal Mine, Inc. in Healy, Alaska were tested in a 10-lb/hr bench-scale inclined fluidized-bed. Experimental results show that the dried coal contains less than 1.5% moisture and has a heating value over 11,500 Btu/lb. The coal fines entrainment can be kept below 15 wt % of the feed. The equilibrium moisture of dried coal was less than 50% of feed coal equilibrium moisture. 7 refs., 60 figs., 47 tabs.

Boysen, J.E.; Cha, C.Y.; Barbour, F.A.; Turner, T.F.; Kang, T.W.; Berggren, M.H.; Hogsett, R.F.; Jha, M.C.

1990-02-01

81

Behavior of fluorine and chlorine in Spanish coal fired power plants with pulverized coal boilers and fluidized bed boiler  

Microsoft Academic Search

Behavior and contents of fluorine and chlorine in coal feedstock, combustion wastes (slag and fly ash) and emissions were studied in five conventional coal fired power plants and in a fluidized bed coal power plant. The halide levels found in the used coal were quite low. Mass balances and emission factors were calculated. The volatility of these elements makes the

2003-01-01

82

Turbulent coal flames; fluidized-bed coal combustion  

SciTech Connect

Experimental results are reported from an ongoing combustion characterization study on coal-water slurries (CWS) being conducted at the MIT Combustion Research Facility (CRF). The objectives of the study are to characterize CWS flames, obtained under a variety of input conditions characteristic of boiler operation, with respect to ignition, flame stability, carbon conversion efficiency, radiative heat transfer, gaseous pollutant emissions (NO/sub x/) and the physical-chemical nature of the in-flame particulate matter and ash deposits formed upon the fireside surfaces of the combustion chamber. Combustion tests were carried out with a coal-water slurry provided by the Occidental Research Corporation, containing 70% coal by weight. The slurry was formulated using an Eastern Kentucky bituminous coal of the Island Creek Coal Company, and was ground to produce a bimodal size distribution to facilitate a high coal mass loading. The major input and operating variables examined in the study include atomizer spray quality and pattern, combustion air swirl and exit velocity at the burner, and heat extraction at the burner and along the combustion chamber length. The measurements include determinations of in-flame temperatures and gaseous/solids species concentrations, the axial distribution of radiative heat flux from the flame to the bounding surfaces of the combustion chamber, and the characterization of a number of in-flame particulate and ash deposit samples by scanning electron microscopy and energy dispersive x-ray spectrometry. The experiments have demonstrated that CWS ignition and flame stability, carbon ignition and flame stability, carbon conversion efficiency, ash deposition and NO/sub x/ emission all raise potentially serious technical problems, but that these problems can be solved or ameliorated by careful selection of fuel properties and flame input conditions. 4 references, 33 figures, 5 tables.

Beer, J.M.; Farmayan, W.F.; Monroe, L.S.; Srinivasachar, S.; Teare, J.D.

1983-01-01

83

Mild gasification of Usibelli coal in an inclined fluidized-bed reactor  

SciTech Connect

Results of mild gasification tests of minus 16-mesh Usibelli coal in an inclined fluidized-bed reactor are described in this report. The minus 16-mesh fraction was separated from the coal by screening. The coal was dried to zero moisture content, and about 2 wt % of the volatiles was removed as gas by partial decarboxylation using a 100-lb/hr inclined fluidized-bed dryer. The dried coal was subjected to mild gasification at maximum temperatures of 1050 to 1250{degrees}F (566 to 677{degrees}C) and feed rates of 7.5 lb/hr while using a once-through flow of carbon dioxide as fluidizing gas in a 1-inch-wide, inclined fluidized-bed reactor. Mild gasification of the dried coal resulted in production of 44 to 56 wt % of the dried coal as char, 10 to 13 wt % as liquids, 17 to 28 wt % as gas, and 8 to 21 wt % as fines. The yield of moisture- and ash-free (MAF) liquids varied from 11.4 to 14.2 wt % of the dried coal feed. Chemical analysis was carried out on these products.

Merriam, N.W.; Thomas, K.P.; Cha, C.Y.

1991-02-01

84

A pressurized fluidized bed coal fired combined cycle electric power generation  

Microsoft Academic Search

The combination of pressurized fluidized bed (PFB) technology and the gas-turbine - steam-turbine combined-cycle power system offers a unique opportunity for the production of clean cost-competitive electric power from the combustion of high-sulfur coal. It also offers the prospect of earlier commercialization than those systems requiring gasification or liquification of coal to clean fuels. The U.S. Energy Research and Development

S. Moskowitz

1977-01-01

85

Pulsed atmospheric fluidized bed combustion. Technical progress report, July 1991--September 1991  

SciTech Connect

The major accomplishments during this reporting period include completion of Task 1 and progression into Phase II, Task 2 design activities. A brief laboratory-scale test was conducted during this reporting period to confirm heat transfer coefficients for various sections of the Pulsed Atmospheric Fluidized bed Combustion (PAFBC) system. The heat transfer coefficient was determined to be approximately 50 Btu/hr ft{sup 2} {degrees}F inside the eductor and tailpipe of the pulse combustor as thin the fluidized bed. well as for the surfaces immersed within the fluidized bed. Communications with potential host sites for the Phase III field demonstration activities continued during this reporting period. These discussions along with discussions with environmental regulatory personnel in the State of Maryland indicate that the throughput of the field demonstration facility should be increased to greater than 36 million Btu/hr. An 8 in. {times} 8 in. fluidized bed unit would be too small to satisfy this requirement; its projected firing rate is only 33 million Btu/hr. Major effort during this reporting period was devoted to assessing the reasonableness of increasing the size of the field test facility from a technical and cost standpoint.

Not Available

1991-10-01

86

Toxicological effects on mice following inhalation exposures to fluidized-bed coal combustor fly ash  

SciTech Connect

Toxicological effects of exposure to reaerosolized fly ash from a fluidized-bed coal combustor were evaluated in mice following 500- and 1000-hr inhalation exposures. Alveolar macrophage function, organ histology, and hematopoiesis were assessed following 24-hr/day exposures in two 500-hr experiments. There was little mutagenicity detected by the Ames assay in the samples of the fly ash tested. The chemical characteristics of the fly ash were very similar to those of fly ash produced during conventional coal combustion. However, physical characterization revealed that fluidized-bed combustion fly ash was not fused as is commonly the case in conventionally combusted fly ash, and as a result had a very large surface area. The function of the alveolar macrophages of exposed mice was impaired, and there were significant changes in the histology of the lung, including cellular infiltration and hyperplasia of bronchiolar and alveolar epithelium. These changes are characteristic of pulmonary responses to chronic irritation of the lung.

Kirchner, F.R.; Reilly, C.A. Jr.; Buchholz, D.M.; Pahnke, V.A. Jr.

1983-12-01

87

Toxicological effects on mice following inhalation exposures to fluidized-bed coal combustor fly ash  

SciTech Connect

Toxicological effects of exposure to reaerosolized fly ash from a fluidized-bed coal combustor were evaluated in mice following 500- and 1000-hr inhalation exposures. Alveolar macrophage function, organ histology, and hematopoiesis were assessed following 24-hr/day exposures in two 500-hr experiments. There was little mutagenicity detected by the Ames assay in the samples of the fly ash tested. The chemical characteristics of the fly ash were very similar to those of fly ash produced during conventional coal combustion. However, physical characterization revealed that the fluidized-bed combustion fly ash was not fused as is commonly the case in conventionally combusted fly ash, and as a result had a very large surface area. The function of the alveolar macrophages of exposed mice was impaired, and there were significant changes in the histology of the lung, including cellular infiltration and hyperplasia of bronchiolar and alveolar epithelium. These changes are characteristic of pulmonary responses to chronic irritation of the lung.

Kirchner, F.R.; Reilly, C.A. Jr.; Buchholz, D.M.; Pahnke, V.A. Jr.

1983-01-01

88

Conceptual Design of an Atmospheric Fluidized-Bed Combustion Electric Power Generating Plant. Monthly Technical Report for September 1977.  

National Technical Information Service (NTIS)

Progress in developing the conceptual design and in performing environmental impact and cost analyses for an atmospheric fluidized-bed electric power generating plant is reported. Specifications and drawings for the plant are being completed. Vendor respo...

E. J. Cosgrove

1977-01-01

89

Pressurized Fluidized Bed Combustion of Coal for Electric Power Generation The AEP Approach  

Microsoft Academic Search

American Electric Power (AEP), STAL-LAVAL Turbine A.B. (SL), and Deutsche Babcock Anlagen AG (DBA) are working on a program estimated to cost $250 million that will lead toward the construction of a large (170,000 KW) commercial demonstration of an advanced electric power plant incorporating Pressurized Fluidized Bed Combustion (PFBC) of coal. A pilot plant test program carried out during 1977-1980

J. J. Markowsky; A. L. Jacob; L. P. O'connell; B. Wickstrom; U. Urban

1982-01-01

90

The study of partitioning of heavy metals during fluidized bed combustion of sewage sludge and coal  

Microsoft Academic Search

The behavior of Cd, Cr, Cu, Co, Mn, Ni, Pb, Zn, and Hg during the combustion tests of a dry granular sewage sludge on a fluidized bed combustor pilot (FBC) of about 0.3 MW was evaluated. The emissions of these heavy metals from mono-combustion were compared with those of co-combustion of the sludge with a bituminous coal. The effect of

I. Gulyurtlu; M. Helena Lopes; P. Abelha; I. Cabrita; J. F. Santos Oliveira

2006-01-01

91

Materials performance in the atmospheric fluidized-bed cogeneration air heater experiment  

SciTech Connect

The Atmospheric Fluidized-Bed Cogeneration Air Heater Experiment (ACAHE) sponsored by the US Department of Energy (DOE) was initiated to assess the performance of various heat-exchanger materials to be used in fluidized-bed combustion air heater systems. Westinghouse Electric Corporation, through subcontracts with Babcock & Wilcox, Foster Wheeler, and ABB Combustion Engineering Systems, prepared specifications and hardware for the ACAHE tests. Argonne National Laboratory contracted with Rockwell International to conduct tests in the DOE atmospheric fluidized-bed combustion facility. This report presents an overview of the project, a description of the facility and the test hardware, the test operating conditions, a summary of the operation, and the results of analyzing specimens from several uncooled and cooled probes exposed in the facility. Extensive microstructural analyses of the base alloys, claddings, coatings, and weldments were performed on specimens exposed in several probes for different lengths of time. Alloy penetration data were determined for several of the materials as a function of specimen orientation and the exposure location in the combustor. Finally, the data were compared with earlier laboratory test data, and the long-term performance of candidate materials for air-heater applications was assessed.

Natesan, K.; Podolski, W.; Wang, D.Y.; Teats, F.G. [Argonne National Lab., IL (United States); Gerritsen, W.; Stewart, A.; Robinson, K. [Rockwell International Corp., Canoga Park, CA (United States)

1991-02-01

92

Materials performance in the atmospheric fluidized-bed cogeneration air heater experiment  

SciTech Connect

The Atmospheric Fluidized-Bed Cogeneration Air Heater Experiment (ACAHE) sponsored by the US Department of Energy (DOE) was initiated to assess the performance of various heat-exchanger materials to be used in fluidized-bed combustion air heater systems. Westinghouse Electric Corporation, through subcontracts with Babcock Wilcox, Foster Wheeler, and ABB Combustion Engineering Systems, prepared specifications and hardware for the ACAHE tests. Argonne National Laboratory contracted with Rockwell International to conduct tests in the DOE atmospheric fluidized-bed combustion facility. This report presents an overview of the project, a description of the facility and the test hardware, the test operating conditions, a summary of the operation, and the results of analyzing specimens from several uncooled and cooled probes exposed in the facility. Extensive microstructural analyses of the base alloys, claddings, coatings, and weldments were performed on specimens exposed in several probes for different lengths of time. Alloy penetration data were determined for several of the materials as a function of specimen orientation and the exposure location in the combustor. Finally, the data were compared with earlier laboratory test data, and the long-term performance of candidate materials for air-heater applications was assessed.

Natesan, K.; Podolski, W.; Wang, D.Y.; Teats, F.G. (Argonne National Lab., IL (United States)); Gerritsen, W.; Stewart, A.; Robinson, K. (Rockwell International Corp., Canoga Park, CA (United States))

1991-02-01

93

Temperatures of coal particle during devolatilization in fluidized bed combustion reactor  

SciTech Connect

The purpose of this study was to investigate the thermal behavior of coal during devolatilization in fluidized bed. Temperatures in the center of single coal particle were measured by thermocouple. Two coals were tested (brown coal Bogovina and lignite Kosovo), using dry coal particle, shaped into spherical form of diameters 7 and 10 mm, in temperature range from 300 to 850{sup o}C. Unsteady behavior of coal particle during heating and devolatilization in fluidized bed was described by a model that takes into account heat transfer between bed and particle surface, heat transfer through particle and an endothermic chemical reaction of first-order. Based on the mathematical model analysis and compared with experimental results, values of heat conductivity {lambda}{sub C} and heat capacity (C-p) of coal were determined. The best agreement was obtained for constant thermal properties, for brown coal {lambda}{sub C} = 0.20 W/mK and C{sub p} = 1200 J/kgK and for lignite {lambda}{sub C} = 0.17 W/mK and C-p = 1100 J/kgK.

Komatina, M.; Manovic, V.; Saljnikov, A. [University of Belgrade, Belgrade (Serbia). Faculty of Mechanical Engineering

2006-11-15

94

Measurement of alkali-vapor emission from pressurized fluidized-bed combustion of Illinois coals  

SciTech Connect

Two Illinois Herrin No. 6 coals and one Illinois Springfield No. 5 coal were separately combusted in a laboratory-scale (15-cm dia) pressurized fluidized-bed combustor (PFBC) combined with an alkali sorber. These coals were combusted in a fluidized bed of Tymochtee dolomite at temperatures ranging from 910 to 950[degree]C and a system pressure of 9.2 atm absolute. Alkali-vapor emission (Na and K) in the PFBC flue gas was determined by the analytical activated-bauxite sorber bed technique developed at Argonne National Laboratory. The test results showed that sodium is the major alkali-vapor species present in the PFBC flue gas, and that the level of sodium-vapor emission increases linearly with both Na and Cl contents in the coals. This suggests that the sodium-vapor emission results from direct vaporization of NaCl present in the coals. The measured alkali-vapor concentration (Na + K), 67 to 190 ppbW, is more than 2.5 times greater than the allowable alkali limit of 24 ppb for an industrial gas turbine. Combusting these coals in a PFBC for power generation may require developing a method to control alkali vapors.

Lee, S.H.D.; Teats, F.G.; Swift, W.M. (Argonne National Lab., IL (United States)); Banerjee, D.D. (Illinois Clean Coal Inst., Carterville, IL (United States))

1993-01-01

95

Measurement of alkali-vapor emission from pressurized fluidized-bed combustion of Illinois coals  

SciTech Connect

Two Illinois Herrin No. 6 coals and one Illinois Springfield No. 5 coal were separately combusted in a laboratory-scale (15-cm dia) pressurized fluidized-bed combustor (PFBC) combined with an alkali sorber. These coals were combusted in a fluidized bed of Tymochtee dolomite at temperatures ranging from 910 to 950{degree}C and a system pressure of 9.2 atm absolute. Alkali-vapor emission (Na and K) in the PFBC flue gas was determined by the analytical activated-bauxite sorber bed technique developed at Argonne National Laboratory. The test results showed that sodium is the major alkali-vapor species present in the PFBC flue gas, and that the level of sodium-vapor emission increases linearly with both Na and Cl contents in the coals. This suggests that the sodium-vapor emission results from direct vaporization of NaCl present in the coals. The measured alkali-vapor concentration (Na + K), 67 to 190 ppbW, is more than 2.5 times greater than the allowable alkali limit of 24 ppb for an industrial gas turbine. Combusting these coals in a PFBC for power generation may require developing a method to control alkali vapors.

Lee, S.H.D.; Teats, F.G.; Swift, W.M. [Argonne National Lab., IL (United States); Banerjee, D.D. [Illinois Clean Coal Inst., Carterville, IL (United States)

1993-04-01

96

Co-firing of paper mill sludge and coal in an industrial circulating fluidized bed boiler.  

PubMed

Co-firing of coal and paper mill sludge was conducted in a 103 MWth circulating fluidized bed boiler to investigate the effect of the sludge feeding rate on emissions of SOx, NOx, and CO. The preliminary results show that emissions of SOx and Nx decrease with increasing sludge feeding rate, but CO shows the reverse tendency due to the decrease in combustion temperature caused by a large amount of moisture in the sludge. All emissions met the local environmental requirements. The combustion ashes could be recycled as feed materials in the cement manufacturing process. PMID:12099502

Tsai, Meng-Yuan; Wu, Keng-Tung; Huang, Chin-Cheng; Lee, Hom-Ti

2002-01-01

97

PSNH's Northern Wood power project repowers coal-fired plant with new fluidized-bed combustor  

SciTech Connect

The Northern Wood Power project permanently replaced a 50-MW coal-burning boiler (Unit 5) at Public Service of New Hampshire's Schiller station with a state-of-the-art circulating fluidized bed wood-burning boiler of the same capacity. The project, completed in December 2006, reduced emissions and expanded the local market for low-grade wood. For planning and executing the multiyear, $75 million project at no cost to its ratepayers, PSNH wins Power's 2007 Marmaduke Award for excellence in O & M. The award is named for Marmaduke Surfaceblow, the fictional marine engineer/plant troubleshoot par excellence. 7 figs., 1 tab.

Peltier, R.

2007-08-15

98

Gas characterizaton from fluidized bed coal gasification. Final report  

Microsoft Academic Search

A test program was carried out in which emissions from the Westinghouse pilot scale coal gasifier were characterized. The emissions of primary concern in this study were alkali species, hydrocarbons and particulate matter. The purpose for characterizing these contaminants was to anticipate their effect on downstream process equipment and the potential for environmental impact. The alkali sampling\\/analysis effort showed that

D. F. Ciliberti; E. E. Smeltzer; N. T. Rohatgi; M. A. Alvin; D. L. Keairns; A. B. Turner; F. Lagonik; D. Lojek

2008-01-01

99

Simulation of coal gasification in a fluidized bed  

SciTech Connect

In this analysis of coal gasification, a fundamental approach is used where a set of multiphase (Eulerian) fluid dynamic equations, obtained either by a suitable averaging technique (Anderson and Jackson, 1976; Drew, 1971) or the formulations of continuum mechanics (Drew, 1983), is used to describe the conservation of mass, momentum, and energy for three interpenetrating phases. The particles, like the fluidizing gas, are described as interpenetrating continua. Different particle types are treated as distinct phases; in this study, the feed coal and the bed char are represented as separate phases in order to account for their different histories. Constitutive laws account for the exchange of momentum between phases (``drag``) and interphase energy transfer. The stresses within the granular phases are determined by a formulation based on the kinetic theory, characterized by a ``granular temperature``. A computer code, based on this multiphase hydrodynamic model, has been developed at the Morgantown Energy Technology Center for the detailed simulation of gas and particle dynamics in heavily loaded coal conversion processes (Syamlal, Rogers, O`Brien, 1994; Syamlal, 1995). The hydrodynamic simulation showed the reactor operated in a jetting/bubbling mode. A gas jet penetrated a considerable distance into the bed, and then detached as ``bubbles`` which rose to the top of the column. The reaction scheme indicated that the feed coal did not begin to devolatilize until it had traversed this region, because of the time required to heat up. Thus, volatiles were not released in the jetting region of the bed, but higher in the bed. The oxygen fed with the coal, however, reacted immediately with the recirculating hot char. The net effect of the char reaction scheme was to created. CO, which burned in the region where.the jet detached, creating a, fairly stable ``flame``. The tar reaction scheme indicated that none of the tar escaped the bed.

O`Brien, T.J.

1996-12-31

100

Scale-up of circulating fluidized bed coal combustors  

SciTech Connect

This experimental project has been aimed at quantifying the effects of scale-up upon the hydrodynamics of CFB coal combustors. To this end, we have constructed a cold CFB facility with the ability to recirculate, -- rather than discard, -- fluidization gas mixtures of adjustable density and viscosity. Hydrodynamic analogy between the cold bed and a coal combustor is achieved by matching all relevant dimensionless parameters (Glicksman, 1984; Louge, 1987). Several choices of gas composition and particle properties make the cold flow analogous to that in combustors of diameters in the range 0.3 to 1m. Therefore, for the first time, scale-up effects are quantified directly using cold flow facility. 8 refs.

Louge, M.Y.

1991-01-01

101

Heat and mass transfer in fluidized-bed furnaces in combustion of a coal-water mixture  

NASA Astrophysics Data System (ADS)

The possibility in principle of burning highly ballasted fuel, including irrigated fuel, is considered. The permissible limits of the ash content and the moisture content are determined. The process of the thermal interaction between a drop of a coal-water mixture (CWM) and a fluidized bed is analyzed. Calculations of the distribution of volatiles and moisture in the fluidized bed in one-sided introduction of CWM are performed. The combustion of a CWM in a boiler furnace confirmed the practical possibility and expediency of recovering irrigated fuel waste of coal cleaning by this method.

Berg, B. V.; Bogatova, T. F.

1996-11-01

102

The simulation of influence of different coals on the circulating fluidized bed Boiler's combustion performance  

NASA Astrophysics Data System (ADS)

The combustion performance of the boiler largely depends on the coal type. Lots of experimental research shows that different fuels have different combustion characteristics. It is obvious that fuel will change the whole operating performance of Circulating Fluidized Bed Combustion (CFBC). We know even in a pilot-scale running boiler, the measurement of some parameters is difficult and costly. Therefore, we developed the way of simulation to evaluate the combustion performance of Chinese coals in CFB. The simulation results show that, different coals will result in different coal particle diameter and comminution depending on their mineral component and the change will affect the distribution of ash in CFBC system. In a word, the computational results are in accordance with experimental results qualitatively but there are some differences quantitatively.

Yong, Yumei; Lu, Qinggang

2003-05-01

103

Atmospheric Fluidized Bed Combustion testing of North Dakota lignite  

SciTech Connect

The sulfur retention by the inherent alkali, and added limestone sorbent, perform about the same and are reasonably predictable within a range of about +-10% retention by application of alkali to sulfur ratio. Temperature has a substantial effect on the retention of sulfur by the inherent alkali or limestone. The temperature effect is not yet fully understood but it appears to be different for different coals and operational conditions. The emission of SO/sub 2/ from the fluid bed burning the Beulah lignite sample used for these tests can be controlled to meet or better the current emission standards. The injection of limestone to an alkali-to-sulfur molar ratio of 1.5 to 1, should lower the SO/sub 2/ emissions below the current requirement of 0.6 lb SO/sub 2//10/sup 6/ Btu to 0.4 lb SO/sub 2//10/sup 6/ Btu, a safe 33% below the standard. Agglomeration of bed material, and consequent loss of fluidization quality can be a problem when burning high sodium lignite in a silica bed. There appears, however, to be several ways of controlling the problem including the injection of calcium compounds, and careful control of operating conditions. The heat transfer coefficients measured in the CPC and GFETC tests are comparable to data obtained by other researchers, and agree reasonably well with empirical conditions. The NO/sub x/ emissions measured in all of the tests on Beulah lignite are below the current New Source Performance Standard of 0.5 lb NO/sub 2//10/sup 6/ Btu input. Combustion efficiencies for the Beulah lignite are generally quite high when ash recycle is being used. Efficiencies in the range of 98% to 99%+ have been measured in all tests using this fuel.

Goblirsch, G; Vander Molen, R H; Wilson, K; Hajicek, D

1980-05-01

104

Preliminary Assessment of the Health and Environmental Impacts of Fluidized-Bed Combustion of Coal as Applied to Electrical Utility Systems.  

National Technical Information Service (NTIS)

The objective of this study was to assess the health and environmental impacts of fluidized-bed combustion of coal (FBC), specifically as applied to base-load generation of electrical energy by utilities. The public health impacts of Fluidized-Bed Combust...

1977-01-01

105

Co-firing a pressurized fluidized-bed combustion system with coal and refuse derived fuels and/or sludges. Task 16  

SciTech Connect

The co-firing of waste materials with coal in utility scale power plants has emerged as an effective approach to produce energy and manage municipal waste. Leading this approach, the atmospheric fluidized-bed combustor (AFBC) has demonstrated its commercial acceptance in the utility market as a reliable source of power burning a variety of waste and alternative fuels. The fluidized bed, with its stability of combustion, reduces the amount of thermochemical transients and provides for easier process control. The application of pressurized fluidized-bed combustor (PFBC) technology, although relatively new, can provide significant enhancements to the efficient production of electricity while maintaining the waste management benefits of AFBC. A study was undertaken to investigate the technical and economic feasibility of co-firing a PFBC with coal and municipal and industrial wastes. Focus was placed on the production of electricity and the efficient disposal of wastes for application in central power station and distributed locations. Wastes considered for co-firing include municipal solid waste (MSW), tire-derived fuel (TDF), sewage sludge, and industrial de-inking sludge. Issues concerning waste material preparation and feed, PFBC operation, plant emissions, and regulations are addressed. This paper describes the results of this investigation, presents conclusions on the key issues, and provides recommendations for further evaluation.

DeLallo, M.; Zaharchuk, R.

1994-01-01

106

COMBUSTION OF OIL SHALE IN FLUIDIZED-BED COMBUSTORS: AN OVERVIEW  

EPA Science Inventory

The report gives an overview of the combustion of oil shale in fluidized-bed combustors. Oil shale can be combusted directly, or as a supplement to coal fuel, and can function as an SO2 sorbent in atmospheric fluidized-bed combustion (AFBC). Spent shale from retorting processes m...

107

Plastic waste elimination by co-gasification with coal and biomass in fluidized bed with air in pilot plant  

Microsoft Academic Search

Treatment of plastic waste by gasification in fluidized bed with air using dolomite as tar cracking catalyst has been studied. The gasifier has a 1 m high bed zone (diameter of 9.2 cm) followed by a 1 m high freeboard (diameter of 15.4 cm). The feedstock is composed of blends of plastic waste with pine wood sawdust and coal at

María P. Aznar; Miguel A. Caballero; Jesús A. Sancho; E. Francés

2006-01-01

108

Fluidized-Bed Regeneration of Sulfated Dolomite from a Coal-Fired FBC Process by Reductive Decomposition.  

National Technical Information Service (NTIS)

A process for regenerating spent SO sub 2 sorbents has been developed on a PDU scale. Tymochtee dolomite that had been sulfated during fluidized-bed combustion of coal is regenerated (reductive decomposition of CaSO sub 4 to CaO and SO sub 2 ) by the inco...

J. C. Montagna G. J. Vogel G. W. Smith A. A. Jonke

1977-01-01

109

Assessment of preliminary steam generator designs for an atmospheric fluidized bed combustion demonstration power plant. Final report  

Microsoft Academic Search

In September 1976, TVA initiated Phase I of a program leading to design and construction of an atmospheric fluidized bed combustion (AFBC) demonstration power plant. The objective was to prepare a preliminary design and cost estimate on which to base decisions to proceed to subsequent phases and to initiate planning necessary to make a major addition to the TVA power

Fourroux

1978-01-01

110

Attrition of coal ash particles in a fluidized-bed reactor  

SciTech Connect

Experimental data of ash-particles attrition in a fluidized bed is presented, and also the results of modeling. Five sizes of ash particles (1.02-1.25; 1.25-1.6; 1.6-2.0; 2.0-5.0; 5.0-10.0 mm) produced in an industrial CFB boiler were examined. A new model of mechanical attrition has been proposed which incorporates new parameters: the shape factor of particles and the ratio of the bed height to bed diameter, strongly influencing the rate of bed mass loss. The model describes very well experimental data for coal-ash particles attrition. The attrition-rate coefficient for ash particles was evaluated.

Tomeczek, J.; Mocek, P. [Silesian Technical University, Katowice (Poland)

2007-05-15

111

Some features of the technology for thermochemical reprocessing of coals in a circulating fluidized bed  

NASA Astrophysics Data System (ADS)

Results from theoretical investigations into transfer processes during the combustion of anthracite culm in a circulating fluidized bed furnace are presented. A method is described according to which hot air is separately admitted into the furnace: the primary air, to under the fluidized-bed grate, and the secondary air, to over its upper boundary. Calculation results together with their discussion are presented.

Rokhman, B. B.

2007-06-01

112

Reduction of iron ore fines by coal fines in a packed bed and fluidized bed apparatus—A comparative study  

NASA Astrophysics Data System (ADS)

Reduction of iron ore fines by coal fines in packed and fluidized beds has been studied. The investigation includes study of the kinetic aspects of reduction, carbon and sulfur content of the direct reduced iron (DRI) produced, and metallography of the products. For both processes, the kinetic data fit the first-order reaction model. Reduction in a fluidized bed is much faster than in a packed bed system. In both cases, DRI contains a substantial amount of free carbon at the initial stages of reduction. At the later stages of reduction, the carbon present in the DRI is mainly in the combined state. For identical temperatures and particle sizes, reaction in fluidized bed is much faster compared to that in a packed bed. At any particular degree of reduction, sulfur content in DRI samples produced by fluidized bed reduction is always more than that of DRI samples produced by packed bed reduction. Scanning electron microscopy (SEM) micrographs reveal that metallic whiskers formed during reduction in packed beds only. These whiskers become more prominent at higher temperatures and longer times.

Haque, R.; Ray, H. S.; Mukherjee, A.

1993-06-01

113

Supportive Studies in Fluidized-Bed Combustion. Annual Report, July 1976--June 1977.  

National Technical Information Service (NTIS)

These studies support the development studies for atmospheric and pressurized fluidized-bed coal combustion. Laboratory and bench-scale studies aimed at providing needed information on combustion optimization, sorbent regeneration process development, sol...

G. J. Vogel I. Johnson S. H. Lee

1977-01-01

114

Supportive Studies in Fluidized-Bed Combustion. Quarterly Report, January--March 1977.  

National Technical Information Service (NTIS)

These studies support the development studies for atmospheric and pressurized fluidized-bed coal combustion. Laboratory and bench-scale studies aimed at providing needed information on combustion optimization, regeneration process development, solid waste...

G. J. Vogel I. Johnson S. H. Lee

1977-01-01

115

Supportive Studies in Fluidized-Bed Combustion. Quarterly Report, July--September 1977.  

National Technical Information Service (NTIS)

These studies support the development studies for atmospheric and pressurized fluidized-bed coal combustion. Laboratory and bench-scale (process development unit) studies are aimed at providing needed information on regeneration process development, contr...

G. J. Vogel I. Johnson S. H. Lee

1977-01-01

116

Hydrodynamic behavior of a liquid-solid fluidized-bed reactor for the bioconversion of coal particles to liquid products  

SciTech Connect

A predictive mathematical model based on particle convection and dispersion is presented for a liquid fluidized bed of coal particles. The numerical representation can follow transient behavior of liquid fluidized beds that contain a defined particle-size distribution. The calculations exhibited excellent agreement when compared to experimental transient pressure-drop data from a column containing particles of Illinois No. 6 bituminous coal in the size range of 20 to 120 {mu}m. In addition, the model was used to simulate the effect of periodic (hourly) liquid velocity step changes on elutriation of small particles from a given particle-size distribution of 34.5 to 75.5 {mu}m. For the situation tested, the calculations indicate that (a) the column does not reach a steady state between velocity changes and (b) that higher initial particle elutriation rates decay to lower values until no more particles elutriate from the column.

Scott, T.C.; Kaufman, E.N.; Cosgrove, J.M. [Oak Ridge National Lab., TN (United States); Asif, M.; Petersen, J.N. [Washington State Univ., Pullman, WA (United States). Dept. of Chemical Engineering

1993-10-01

117

Design of a 165 MWe reheat coal-fired circulating fluidized bed boiler for Nova Scotia Power Corporation  

SciTech Connect

In October 1989, a contract was awarded to Pyropower Corporation for the design, supply and erection of the 165 MW{sub e} reheat coal fired circulating fluidized bed boiler for the Point Aconi site in Nova Scotia, Canada. This order represented the largest capacity circulating fluidized bed (CFB) boiler sold to date. This paper presents the boiler design parameters, design arrangement and specific, unique design features such as the reheat system and reheat temperature control. A particular concern with the boiler design was the relatively high chlorine content in the coal fuel. To resolve this concern, a test burn was conducted in Pyropower's Research and Development facility in December 1989. The test burn and it's results are also examined.

Schaller, B. (Pyropower Corp. (US)); Darguzas, J. (Sargent and Lundy, Chicago, IL (USA)); Fraser, S. (Nova Scotia Power Corp., Halifax, NS (Canada))

1990-01-01

118

Nitric Oxide Reduction over Sewage Sludge and Coal Chars at Conditions Relevant to Staged Fluidized Bed Combustion  

NASA Astrophysics Data System (ADS)

The de-NOx potential of coal and of dried and pelletized sewage sludge, a waste-derived fuel candidate for cofiring with coal, is assessed. The experimental procedure is based on operation of a bench scale fluidized bed reactor where NO-doped nitrogen is contacted with batches of the fuel. A second type of experiment has been purposely designed to assess the loss of reactivity of chars toward gasification by NOx as char is heat-treated for pre-set times at temperatures typical of fluidized bed combustion. A simple phenomenological model is developed to shed light on the basic features of the interaction between heterogeneous char-NOx reaction and thermal annealing of the char.

Salatino, P.; Solimene, R.; Chirone, R.

119

Summary evaluation of atmospheric pressure fluidized bed combustion applied to electric utility large steam generators. Volume I. Final report  

Microsoft Academic Search

A fluidized bed combustor (FBC) using limestone to absorb SOâ appears to have sound potential for burning high sulfur eastern coals (which are in ample supply) while staying within anti-pollution regulations. A literature search was conducted by the Alliance Research Center of Babcock and Wilcox for EPRI. The purpose: to collect available FBC data, analyze the state-of-the-art, to make initial

T. E. Dowdy; W. C. Lapple; J. B. Kitto; T. P. Stanoch; R. H. Boll; W. L. Sage; S. S. Strom

1976-01-01

120

Pilot-scale fluidized-bed combustor testing cofiring animal-tissue biomass with coal as a carcass disposal option  

Microsoft Academic Search

This study was performed to demonstrate the technical viability of cofiring animal-tissue biomass (ATB) in a coal-fired fluidized-bed combustor (FBC) as an option for disposing of specified risk materials (SRMs) and carcasses. The purpose of this study was to assess the technical issues of feeding\\/combusting ATB and not to investigate prion deactivation\\/pathogen destruction. Overall, the project successfully demonstrated that carcasses

Bruce G. Miller; Sharon Falcone Miller; Elizabeth M. Fedorowicz; David W. Harlan; Linda A. Detwiler; Michelle L. Rossman

2006-01-01

121

Alkali metals in circulating fluidized bed combustion of biomass and coal: measurements and chemical equilibrium analysis  

SciTech Connect

Combustion and co-combustion experiments with four kinds of straw, specially selected for their different alkali, Cl, and Si contents, and Colombian black coal were carried out in a circulating fluidized bed (CFB) reactor at Delft University of Technology. The influence of operating conditions and fuel composition on the release of the alkali compounds to the gas phase was investigated. The amount of the total gas-phase sodium and potassium compounds in the flue gases was measured with excimer laser induced fluorescence (ELIF). The results show that the release of gaseous alkali species depends on fuel composition, in particular the K/Cl and K/Si ratios in the fuel. The fuels with high K and Cl values show higher concentrations of the gaseous alkalis. A synergetic effect of the co-combustion with coal was observed, which led to a strong decrease in gaseous alkali concentrations. Together with experiments, chemical equilibrium modeling was performed to help in interpreting the experimental data. The calculations confirmed that the equilibrium is very strongly influenced by the composition of the fuel blend. Moreover, the simulations provided more information on sequestering of alkali species. 22 refs., 5 figs., 4 tabs.

Michal P. Glazer; Nafees A. Khan; Wiebren de Jong; Hartmut Spliethoff; Heiko Schuermann; Penelope Monkhouse [Delft University of Technology, Delft (Netherlands). Section Energy Technology

2005-10-01

122

Hydrogen-rich gas production by cogasification of coal and biomass in an intermittent fluidized bed.  

PubMed

This paper presents the experimental results of cogasification of coal and biomass in an intermittent fluidized bed reactor, aiming to investigate the influences of operation parameters such as gasification temperature (T), steam to biomass mass ratio (SBMR), and biomass to coal mass ratio (BCMR) on hydrogen-rich (H2-rich) gas production. The results show that H2-rich gas free of N2 dilution is produced and the H2 yield is in the range of 18.25~68.13?g/kg. The increases of T, SBMR, and BCMR are all favorable for promoting the H2 production. Higher temperature contributes to higher CO and H2 contents, as well as H2 yield. The BCMR has a weak influence on gas composition, but the yield and content of H2 increase with BCMR, reaching a peak at the BCMR of 4. The H2 content and yield in the product gas increase with SBMR, whilst the content of CO increases first and then decreases correspondingly. At a typical case, the relative linear sensitivity coefficients of H2 production efficiency to T, SBMR, and BCMR were calculated. The results reveal that the order of the influence of the operation parameters on H2 production efficiency is T > SBMR > BCMR. PMID:24174911

Wang, Li-Qun; Chen, Zhao-Sheng

2013-09-15

123

Hydrogen-Rich Gas Production by Cogasification of Coal and Biomass in an Intermittent Fluidized Bed  

PubMed Central

This paper presents the experimental results of cogasification of coal and biomass in an intermittent fluidized bed reactor, aiming to investigate the influences of operation parameters such as gasification temperature (T), steam to biomass mass ratio (SBMR), and biomass to coal mass ratio (BCMR) on hydrogen-rich (H2-rich) gas production. The results show that H2-rich gas free of N2 dilution is produced and the H2 yield is in the range of 18.25~68.13?g/kg. The increases of T, SBMR, and BCMR are all favorable for promoting the H2 production. Higher temperature contributes to higher CO and H2 contents, as well as H2 yield. The BCMR has a weak influence on gas composition, but the yield and content of H2 increase with BCMR, reaching a peak at the BCMR of 4. The H2 content and yield in the product gas increase with SBMR, whilst the content of CO increases first and then decreases correspondingly. At a typical case, the relative linear sensitivity coefficients of H2 production efficiency to T, SBMR, and BCMR were calculated. The results reveal that the order of the influence of the operation parameters on H2 production efficiency is T > SBMR > BCMR.

Wang, Li-Qun; Chen, Zhao-Sheng

2013-01-01

124

Cyclone and fluidized bed combustion concepts for coal fired open cycle MHD  

Microsoft Academic Search

Predicted performances of fluidized bed and cyclone combustion schemes were compared as part of a recent conceptual design study of a sub-scale (250 MWt), open-cycle MHD Engineering Test Facility (ETF). Both combustion concepts were two-stage gasification\\/combustion systems designed for high slag\\/ash rejection with predictions for slag\\/ash rejection being greater than 99% and 90% for the fluidized bed and cyclone concepts

S. Omori; J. Hnat; J. Bazan; B. Biswas

1978-01-01

125

Scaled-bed modeling for fluidized-bed combustors. Semi-annual report, October 1, 1980-March 31, 1981  

SciTech Connect

Progress is reported in developing scaled models of coal-fired fluidized-bed combustors which can be used with confidence to obtain performance data for predicting the performance of full scale units. Construction of two 1/4 scale atmospheric pressure fluidized bed combustors is nearing completion. (LCL)

Fitzgerald, T.J.; Crane, S.D.

1981-03-01

126

Emissions of NO x and N 2O during co-combustion of dried sewage sludge with coal in a circulating fluidized bed combustor  

Microsoft Academic Search

Emissions of NOx and N2O were measured during mono-combustion of dried sewage sludge and co-combustion with coal in a bench-scale circulating fluidized bed combustor (CFBC). The results were compared with previous results obtained using a bubbling fluidized bed combustor (BFBC). The increase in NOx with sludge ash accumulation in the combustor was less for the CFBC than the BFBC, partly

Tadaaki Shimizu; Masanori Toyono

2007-01-01

127

Computerized simulation of the dynamic response of a coal-fired power plant with pressurized fluidized bed  

NASA Astrophysics Data System (ADS)

The simple way of desulfurizing, the efficient combustion of coal, and low carbon monoxide flue gas content of a fluidized bed combustion installation were studied. The dynamic response of a pressurized fluidized bed should also be studied before any construction is started. The physical-mathematical models of all single components were developed and combined in a total computer program. Starting point was the planned pilot plant with gas turbine engine. Various modifications of the purely air cooled plant as well as the extension to a combined cycle with additional steam turbine were considered. Operating cases were simulated: starting up, increasing from partial load to full load and vice versa, shut down and breakdowns. Results show that all operating cases could be brought under control as well as breakdowns. The constructive precautions and correct plant practice are described.

Plackmeyer, J.

1982-07-01

128

Engineering Support Services for the DOE/GRI Coal-Gasification Research Program. Technical and Economic Assessment of the Westinghouse Fluidized-Bed Coal Gasification Process.  

National Technical Information Service (NTIS)

Kellogg was requested by DOE/GRI to perform a technical and economic assessment of the Westinghouse fluidized bed coal gasification process as applied to production of SNG equivalent to 250 billion BTU/day from Pittsburgh No. 8 coal. Based on operating ex...

D. A. Hubbard L. E. Bostwick R. W. Laramore T. R. Ethridge

1981-01-01

129

Engineering support services for the DOE\\/GRI coal-gasification research program. Technical and economic assessment of the Westinghouse fluidized-bed coal gasification process  

Microsoft Academic Search

Kellogg was requested by DOE\\/GRI to perform a technical and economic assessment of the Westinghouse fluidized bed coal gasification process as applied to production of SNG equivalent to 250 billion BTU\\/day from Pittsburgh No. 8 coal. Based on operating experiences in the PDU, where most of the key variables have been demonstrated during 5+ years of testing, Westinghouse provided process

L. E. Bostwick; D. A. Hubbard; R. W. Laramore; T. R. Ethridge

1981-01-01

130

Comparion of Mercury Emissions Between Circulating Fluidized Bed Boiler and Pulverized Coal Boiler  

NASA Astrophysics Data System (ADS)

Mercury emissions between a circulating fluidized bed (CFB) utility boiler and two pulverized coal (PC) boilers equipped with electrostatic precipitators (ESP) were in situ measured and compared. The standard Ontario Hydro Method (OHM) was used to sample the flue gas before and after the ESP. Various mercury speciations such as Hg0, Hg2+ and Hgp in flue gas and total mercury in fly ashes were analyzed. The results showed that the mercury removal rate of the CFB boiler is nearly 100%; the mercury emission in stack is only 0.028 g/h. However, the mercury removal rates of the two PC boilers are 27.56% and 33.59% respectively, the mercury emissions in stack are 0.80 and 51.78 g/h respectively. It concluded that components of the ESP fly ashes especially their unburnt carbons have remarkable influence on mercury capture. Pore configurations of fine fly ash particles have non-ignored impacts on mercury emissions.

Wang, Y. J.; Duan, Y. F.; Zhao, C. S.

131

Release of sulfur and chlorine during cofiring RDF and coal in an internally circulating fluidized bed  

SciTech Connect

An internally circulating fluidized bed (ICFB) was applied to investigate the behavior of chlorine and sulfur during cofiring RDF and coal. The pollutant emissions in the flue gas were measured by Fourier transform infrared (FTIR) spectrometry (Gasmet DX-3000). In the tests, the concentrations of the species CO, CO{sub 2}, HCl, and SO{sub 2} were measured online. Results indicated when cofiring RDF and char, due to the higher content of chlorine in RDF, the formation of HCl significantly increases. The concentration of SO{sub 2} is relatively low because alkaline metal in the fuel ash can absorb SO{sub 2}. The concentration of CO emission during firing pure RDF is relatively higher and fluctuates sharply. With the CaO addition, the sulfur absorption by calcium quickly increases, and the desulfurization ratio is bigger than the dechlorination ratio. The chemical equilibrium method is applied to predict the behavior of chlorine. Results show that gaseous HCl emission increases with increasing RDF fraction, and gaseous KCl and NaCl formation might occur. 35 refs., 18 figs., 2 tabs.

Xiaolin Wei; Yang Wang; Dianfu Liu; Hongzhi Sheng; Wendong Tian; Yunhan Xiao [Chinese Academy of Sciences, Beijing (China). Institute of Mechanics, and Institute of Engineering Thermophysics

2009-03-15

132

Hydrodynamics of a fluidized bed co-combustor for tobacco waste and coal.  

PubMed

The fluidization characteristics of binary mixtures containing tobacco stem (TS) and cation exchange resin (a substitute for coal) were studied in a rectangular bed with the cross-section area of 0.3 × 0.025 m(2). The presence of herbaceous biomass particles and their unique properties such as low density and high aspect ratio resulted in different fluidization behaviors. Three fluidization velocities, i.e. initial, minimum and full fluidization velocities, were observed as the TS mass fraction increased from 7% to 20%, and four hydrodynamic stages were experienced, including the static, segregation, transition and mixing stages, with increasing operational gas velocities. The results suggest that the operational gas velocity should be in the range of 2.0-5.0 times of the minimum fluidization velocity of the binary mixtures, and less than 7% TS mass fraction should be used in an existing bubbling fluidized bed. Higher TS fraction inclusion requires the introduction of central jet gas to improve the mixing effect. PMID:22750501

Zhang, Kai; Yu, Bangting; Chang, Jian; Wu, Guiying; Wang, Tengda; Wen, Dongsheng

2012-06-01

133

DOE cost comparison study industrial fluidized bed combustion vs conventional coal technology  

SciTech Connect

This study compares the capital and operating costs of two different industrial boiler technologies, each producing 250,000 lbs steam/hr. These technologies are: Fluidized Bed Combustion (FBC) and Pulverized Coal (PC) combustion used in conjunction with a limestone Flue Gas Desulfurization (FGD) system. Three separate turnkey plant designs have been completed. Two of these plant designs incorporate FBC technology and have been designated FBA-16 and FBV-16. The first FBC design (FBA-16) contains two shop assembled, rail shippable fluid bed boilers capable of producing 125,000 lbs/hr each. The second plant design (FBV-16) utilizes a single 250,000 lbs/hr fluid bed boiler shipped by rail in large sections for field assembly. The third plant design utilizes a conventional pulverized coal (PC) boiler in conjunction with a C-E Air Quality Control System (AQCS) limestone scrubber. Capital costs were generated for the three turnkey plant designs just described. The FBA-16, FBV-16, and Conventional Unit plant designs have associated capital costs of $24.4, $22.8, and $24.7 million, respectively. Comparisons between plant capital cost estimates are valid and informative. The total operational costs, which include contingencies on new product design for the Fluid Bed Units, were found to vary between four and seven percent higher than the Conventional Unit. When contingencies are not included, the operating costs were found to be between one and three percent higher than the Conventional Unit. As can be seen, the operating costs for the bed designs are close enough to be considered similar when considering the nature of the study. The efficiency of the fluid bed plant designs can be increased and required capital equipment reduced by improvements to the plant design with time and more development. Some potential design modifications are outlined.

Myrick, D.T.

1980-01-02

134

DOE cost comparison study: industrial fluidized bed combustion vs conventional coal technology  

SciTech Connect

This study compares the capital and operating costs of two different industrial boiler technologies, each producing 250,000 lbs steam/hr: Fluidized Bed Combustion (FBC) and Pulverized Coal (PC) combustion used in conjunction with a limestone Flue Gas Desulfurization (FGD) system. Three separate turnkey plant designs have been completed. Two of these plant designs incorporate FBC technology and have been designated FBA-16 and FBV-16. The first FBC design (FBA-16) contains two shop assembled, rail-shippable, fluid-bed boilers capable of producing 125,000 lbs/h each. The second plant design (FBV-16) utilizes a single fluid bed boiler shipped by rail in large sections for field assembly. This single unit is capable of producing 250,000 lbs/h. The third plant design utilizes a conventional pulverized coal (PC) boiler used in conjunction with a C-E Air Quaity Control System (AQCS) limestone scrubber. The FBA-16 and FBV-16 fluid bed designs were found to be competitive with the conventional unit. Capital costs were generated for the three turnkey plant designs just described. The FBA-16, FBV-16, and Conventional Unit plant designs have associated capital costs of $24.4, $22.8, and $24.7 million, respectively. A substantial cost reduction can be realized for plant capacities less than 180,000 lbs steam/h by incorporating a single FBA-16 type boiler. The operating costs for the bed designs are close enough to be considered similar when considering the nature of the study. The efficiency of the fluid bed plant designs can be increased and required capital equipment reduced by improvements to the plant design. Some potential design modifications are outlined. Extensive design and background research was prformed to increase the validity and relevance of this report.

Myrick, D.T.

1980-01-02

135

Nucla circulating atmospheric fluidized bed demonstration project. Quarterly technical progress report, October--December 1990.  

National Technical Information Service (NTIS)

During the fourth quarter of 1990, steady-state performance testing at the Nucla Circulating Fluidized Bed (CFB) resumed under sponsorship of the US Department of Energy. Co-sponsorship of the Demonstration Test Program by the Electric Power Research Inst...

1991-01-01

136

Distribution of polycyclic aromatic hydrocarbons in fly ash during coal and residual char combustion in a pressurized fluidized bed  

SciTech Connect

To investigate the distribution of polycyclic aromatic hydrocarbons (PAHs) in fly ash, the combustion of coal and residual char was performed in a pressurized spouted fluidized bed. After Soxhlet extraction and Kuderna-Danish (K-D) concentration, the contents of 16 PAHs recommended by the United States Environmental Protection Agency (U.S. EPA) in coal, residual char, and fly ash were analyzed by a high-performance liquid chromatography (HPLC) coupled with fluorescence and diode array detection. The experimental results show that the combustion efficiency is lower and the carbon content in fly ash is higher during coal pressurized combustion, compared to the residual char pressurized combustion at the pressure of 0.3 MPa. Under the same pressure, the PAH amounts in fly ash produced from residual char combustion are lower than that in fly ash produced from coal combustion. The total PAHs in fly ash produced from coal and residual char combustion are dominated by three- and four-ring PAHs. The amounts of PAHs in fly ash produced from residual char combustion increase and then decrease with the increase of pressure in a fluidized bed. 21 refs., 1 fig., 4 tabs.

Hongcang Zhou; Baosheng Jin; Rui Xiao; Zhaoping Zhong; Yaji Huang [Nanjing University of Information Science and Technology, Nanjing (China)

2009-04-15

137

EMISSIONS FROM FBC (FLUIDIZED-BED COMBUSTION) BOILERS  

EPA Science Inventory

The paper provides perspective regarding the environmental acceptability of atmospheric-pressure fluidized-bed boilers, with particular emphasis on the application of this technology as a technique for utilizing coal in the industrial sector. It reviews emission sources within th...

138

Autothermal gasification of low-grade fuels in fluidized bed  

NASA Astrophysics Data System (ADS)

Autothermal gasification of high-ash floatation wastes of Grade Zh Kuzbass coal and low-ash fuel in a suspended-spouted (fluidized) bed at atmospheric pressure is investigated, and a comparison is presented of experimental results that indicate that the ash content of fuels has only slight influence on the generator gas heating value.

Belyaev, A. A.

2009-01-01

139

Validation testing of the EERC pilot-scale circulating fluidized-bed combustor using Salt Creek coal. Final report  

SciTech Connect

The overall goal of the project was to provide a technical basis for assessing the economic and environmental feasibility of circulating fluidized-bed combustion (CFBC) technology, focusing on the effect of system configuration and coal properties on performance. Other underlying goals of the program were to (1) design and construct a CFBC test facility, thereby providing a test facility at an independent laboratory; (2) demonstrate that the test unit is capable of meeting the original design objectives; and (3) assess the ability of the unit to provide scalable data. The purpose of this interim report is to present data from validation testing to establish the scalability of data generated from this unit.

Mann, M.D.; Hajicek, D.R.; Moe, T.A.; Henderson, A.K.

1991-09-01

140

Validation testing of the EERC pilot-scale circulating fluidized-bed combustor using Salt Creek coal  

SciTech Connect

The overall goal of the project was to provide a technical basis for assessing the economic and environmental feasibility of circulating fluidized-bed combustion (CFBC) technology, focusing on the effect of system configuration and coal properties on performance. Other underlying goals of the program were to (1) design and construct a CFBC test facility, thereby providing a test facility at an independent laboratory; (2) demonstrate that the test unit is capable of meeting the original design objectives; and (3) assess the ability of the unit to provide scalable data. The purpose of this interim report is to present data from validation testing to establish the scalability of data generated from this unit.

Mann, M.D.; Hajicek, D.R.; Moe, T.A.; Henderson, A.K.

1991-09-01

141

Fluidized-bed copper oxide process  

SciTech Connect

The fluidized-bed copper oxide process was developed to simultaneously remove sulfur dioxide and nitrogen oxide contaminants from the flue gas of coal-fired utility boilers. This dry and regenerable process uses a copper oxide sorbent in a fluidized-bed reactor. Contaminants are removed without generating waste material. (VC)

Shah, P.P.; Takahashi, G.S.; Leshock, D.G.

1991-10-14

142

Numerical simulation on pulverized coal combustion and NOx emissions in high temperature air from circulating fluidized bed  

NASA Astrophysics Data System (ADS)

High temperature air combustion is a prospecting technology in energy saving and pollutants reduction. Numerical simulation on pulverized coal combustion and NOx emissions in high temperature air from circulating fluidized bed was presented. The down-fired combustor, taken as the calculation domain, has the diameter of 220 mm and the height of 3000 mm. 2 cases with air staging combustion are simulated. Compared the simulation results with experimental data, there is a good agreement. It is found that the combustion model and NOx formation model are applicable to simulate the pulverized coal combustion and NOx emissions in high temperature air from circulating fluidized bed. The results show that there is a uniform temperature profile along the axis of the down-fired combustor. The NOx emissions are lower than those of ordinary pulverized coal combustion, and the NOx emissions are 390 mg/m3 and 352 mg/m3 in Case 1 and Case 2, respectively. At the range of 300-600 mm below the nozzle, the NO concentration decreases, mainly resulting from some homogeneous reactions and heterogeneous reaction. NO concentration has a little increase at the position of 800 mm below the nozzle as the tertiary air supplied to the combustor at the position of 600 mm below the nozzle.

Zhu, Jianguo; Ouyang, Ziqu; Lu, Qinggang

2013-06-01

143

Performance and economics of co-firing a coal/waste slurry in advanced fluidized-bed combustion  

SciTech Connect

This study`s objective was to investigate co-firing a pressurized fluidized-bed combustor with coal and refuse-derived fuel for the production of electricity and the efficient disposal of waste. Performance evaluation of the pressurized fluidized-bed combustor (PFBC) power plant co-fired with refuse-derived fuel showed only slightly lower overall thermal efficiency than similar sized plants without waste co-firing. Capital costs and costs of electricity are within 4.2 percent and 3.2 percent, respectively, of waste-free operation. The results also indicate that there are no technology barriers to the co-firing of waste materials with coal in a PFBC power plant. The potential to produce cost-competitive electrical power and support environmentally acceptable waste disposal exists with this approach. However, as part of technology development, there remain several design and operational areas requiring data and verification before this concept can realize commercial acceptance. 3 refs., 3 figs., 4 tabs.

DeLallo, M.R.; Zaharchuk, R. [Parsons Power Group, Inc., Reading, PA (United States); Reuther, R.B.; Bonk, D.L. [USDOE Morgantown Energy Technology Center, WV (United States)

1996-09-01

144

Dual Fluidized Bed Biomass Gasification  

SciTech Connect

The dual fluidized bed reactor is a recirculating system in which one half of the unit operates as a steam pyrolysis device for biomass. The pyrolysis occurs by introducing biomass and steam to a hot fluidized bed of inert material such as coarse sand. Syngas is produced during the pyrolysis and exits the top of the reactor with the steam. A crossover arm, fed by gravity, moves sand and char from the pyrolyzer to the second fluidized bed. This sand bed uses blown air to combust the char. The exit stream from this side of the reactor is carbon dioxide, water and ash. There is a second gravity fed crossover arm to return sand to the pyrolysis side. The recirculating action of the sand and the char is the key to the operation of the dual fluidized bed reactor. The objective of the project was to design and construct a dual fluidized bed prototype reactor from literature information and in discussion with established experts in the field. That would be appropriate in scale and operation to measure the relative performance of the gasification of biomass and low ranked coals to produce a high quality synthesis gas with no dilution from nitrogen or combustion products.

None

2005-09-30

145

Comparison of coal/solid recovered fuel (SRF) with coal/refuse derived fuel (RDF) in a fluidized bed reactor.  

PubMed

An experimental study was undertaken to compare the differences between municipal solid waste (MSW) derived solid recovered fuel (SRF) (complying with CEN standards) and refuse derived fuel (RDF). Both fuels were co-combusted with coal in a 50 kW fluidized bed combustor and the metal emissions were compared. Synthetic SRF was prepared in the laboratory by grinding major constituents of MSW such as paper, plastic, textile and wood. RDF was obtained from a local mechanical treatment plant. Heavy metal emissions in flue gas and ash samples from the (coal+10% SRF) fuel mixture were found to be within the acceptable range and were generally lower than that obtained for coal+10% RDF fuel mixture. The relative distribution of heavy metals in ash components and the flue gas stream shows the presence of a large fraction (up to 98%) of most of the metals in the ash (except Hg and As). Thermo-gravimetric (TG) analysis of SRF constituents was performed to understand the behaviour of fuel mixtures in the absence and presence of air. The results obtained from the experimental study will enhance the confidence of fuel users towards using MSW-derived SRF as an alternative fuel. PMID:21288710

Wagland, S T; Kilgallon, P; Coveney, R; Garg, A; Smith, R; Longhurst, P J; Pollard, S J T; Simms, N

2011-02-01

146

Numerical and experimental study of gas–particle radiative heat exchange in a fluidized-bed reactor for steam-gasification of coal  

Microsoft Academic Search

A heat transfer numerical model is developed for the steam-gasification of coal in a fluidized bed contained in a quartz tubular reactor that is directly exposed to concentrated thermal radiation. The Monte Carlo method is applied for solving the radiative exchange within the reactor quartz walls, the bed particles, and the gas phase. The reaction kinetics are described by Langmuir–Hinshelwood

P. von Zedtwitz; W. Lipi?ski; A. Steinfeld

2007-01-01

147

Biomass yield and phosphorus availability to wheat grown on high phosphorus soils amended with phosphate inactivating residues. III. Fluidized bed coal combustion ash  

Microsoft Academic Search

The high phosphorus (P) soils in the poultry producing areas of Maryland's Eastern Shore pose an environmental risk to surface and ground water. Amendments with calcium (Ca) salts and calcium-rich byproducts have been considered in management practices for reducing P solubility in soil solution. A growth chamber experiment was conducted using fluidized bed coal ash (BA) at increasing rates on

Eton E. Codling; Charles L. Mulchi; Rufus L. Chaney

2002-01-01

148

Nucla circulating atmospheric fluidized bed demonstration project. Quarterly technical progress report, October--December 1990  

SciTech Connect

During the fourth quarter of 1990, steady-state performance testing at the Nucla Circulating Fluidized Bed (CFB) resumed under sponsorship of the US Department of Energy. Co-sponsorship of the Demonstration Test Program by the Electric Power Research Institute (EPRI) was completed on June 15, 1990. From October through December, 1990, Colorado-Ute Electric Association (CUEA) completed a total of 23 steady-state performance tests, 4 dynamic tests, and set operating records during November and December as the result of improved unit operating reliability. Highlight events and achievements during this period of operation are presented.

Not Available

1991-01-31

149

Research on coal-water fuel combustion in a circulating fluidized bed / Badanie spalania zawiesinowych paliw w?glowo-wodnych w cyrkulacyjnej warstwie fluidalnej  

NASA Astrophysics Data System (ADS)

In the paper the problem of heavily-watered fuel combustion has been undertaken as the requirements of qualitative coals combusted in power stations have been growing. Coal mines that want to fulfill expectations of power engineers have been forced to extend and modernize the coal enrichment plants. This causes growing quantity of waste materials that arise during the process of wet coal enrichment containing smaller and smaller under-grains. In this situation the idea of combustion of transported waste materials, for example in a hydraulic way to the nearby power stations appears attractive because of a possible elimination of the necessary deep dehydration and drying as well as because of elimination of the finest coal fraction loss arising during discharging of silted water from coal wet cleaning plants. The paper presents experimental research results, analyzing the process of combustion of coal-water suspension depending on the process conditions. Combustion of coal-water suspensions in fluidized beds meets very well the difficult conditions, which should be obtained to use the examined fuel efficiently and ecologically. The suitable construction of the research stand enables recognition of the mechanism of coal-water suspension contact with the inert material, that affects the fluidized bed. The form of this contact determines conditions of heat and mass exchange, which influence the course of a combustion process. The specificity of coal-water fuel combustion in a fluidized bed changes mechanism and kinetics of the process.

Kijo-Kleczkowska, Agnieszka

2012-10-01

150

EXPERIMENTAL/ENGINEERING SUPPORT FOR ENVIRONMENTAL PROTECTION AGENCIES FLUIDIZED-BED COMBUSTION (FBC) PROGRAM: FINAL REPORT. VOLUME I. SULFUR OXIDE CONTROL  

EPA Science Inventory

The report gives results of an investigation of the desulfurization performance and attrition behavior of limestone and dolomite sorbents for atmospheric and pressurized fluidized-bed combustion (FBC) systems used with coal. It gives results of experimental thermogravimetric anal...

151

A coal fired gas turbine using an air cooled fluidized bed combustor  

Microsoft Academic Search

A gas turbine cogeneration system using a coal fired atmospheric fluid bed (AFB) combustor represents an environmentally clean and less costly alternative to the oil or gas fired electric power generators, process steam boilers and process heaters that are necessary for the operations of both small and large industrial energy users. This paper describes a cogeneration system which uses an

S. Moskowitz; J. Mullen; S. Vanderlinden

1983-01-01

152

Effect of cofiring coal and biofuel with sewage sludge on alkali problems in a circulating fluidized bed boiler  

SciTech Connect

Cofiring experiments were performed in a 12 MW circulating fluidized bed boiler. The fuel combinations were biofuel (wood+straw), coal+biofuel, coal+sewage sludge+biofuel, and sewage sludge+biofuel. Limestone or chlorine (PVC) was added in separate experiments. Effects of feed composition on bed ash and fly ash were examined. The composition of flue gas was measured, including on-line measurement of alkali chlorides. Deposits were collected on a probe simulating a superheater tube. It was found that the fuel combination, as well as addition of limestone, has little effect on the alkali fraction in bed ash, while chlorine decreases the alkali fraction in bed ash. Sewage sludge practically eliminates alkali chlorides in flue gas and deposits. Addition of enough limestone to coal and sludge for elimination of the SO{sub 2} emission does not change the effect of chlorine. Chlorine addition increases the alkali chloride in flue gas, but no chlorine was found in the deposits with sewage sludge as a cofuel. Cofiring of coal and biofuel lowers the alkali chloride concentration in the flue gas to about a third compared with that of pure biofuel. This is not affected by addition of lime or chlorine. It is concluded that aluminum compounds in coal and sludge are more important than sulfur to reduce the level of KCl in flue gas and deposits. 24 refs., 8 figs., 7 tabs.

K.O. Davidsson; L.-E. Aamand; A.-L. Elled; B. Leckner [Chalmers University of Technology, Goeteborg (Sweden). Department of Energy and Environment

2007-12-15

153

Materials problems in fluidized-bed combustion systems: review of the information on gas turbine materials in coal combustion environments  

SciTech Connect

This report condenses into a single document the available information related to the performance of gas turbine materials operated in the effluent from the combustion of coal. The information summarized originated from three sources: work performed in the period 1940-1970 to establish the potential for a direct coal-fired gas turbine, actual operating experience of gas turbines in particulate-laden environments, and recent efforts to evaluate gas turbines for firing with a pressurized fluidized-bed combustor. Results of these studies show clearly that the potential for erosion, corrosion, and deposition exists in gas turbines operated on coal to the extent that the performance and endurance may be substantially reduced. The choice of gas turbine materials strongly influenced the lifetimes of components exposed to coal-derived environments. Bare alloys, such as IN-738, U-700, and X-40, exposed to the hot gas path degraded more rapidly than MCrAlY coatings or claddings which produce protective layers of alumina or chromia. Extremely hard coatings containing high concentration of carbides in a ductile matrix were particularly resistant to erosion. The interaction between corrosion and erosion appears to be synergistic; however, the exact relationships between these processes are still unknown.

McCarron, R.L.; Grey, D.A.

1980-08-01

154

The gas turbine heat exchanger in the fluidized bed combustor  

Microsoft Academic Search

In a current research and development program a coal-fired atmospheric fluidized bed combustor is being designed to supply the heat to a closed cycle gas turbine cogeneration system. The major technical effort is directed towards the design of the in-bed heat exchanger, which is required to operate near bed temperature. This high temperature (850° C) exposes the heat exchanger tubes

C. F. Holt; A. A. Boiarski; H. E. Carlton

1983-01-01

155

In Developping a Bench-Scale Circulating Fluidized Bed Combustor to Burn High Ash Brazilian Coal-Dolomites Mixtures  

NASA Astrophysics Data System (ADS)

This work considers some of the questions in burning high ash Brazilian coal-dolomite mixtures in a bench-scale circulating fluidized bed combustor (CFBC). Experimental tests were performed with the CE4500 coal from Santa Catarina State, in southern Brazil, with a Sauter mean diameter d p =43 ?m. The coal particles were mixed with dolomite particles of d p = 111 ?m and this fuel mixture was fed into the circulating fluidized reactor, previously loaded with quartz sand particles of d p =353 ?m. This inert material was previously heated by the combustion of liquefied petroleum gas up to the ignition temperature of the fuel mixture. The CFBC unit has a 100mm internal diameter riser, 4.0m high, as well as a 62.8mm internal diameter downcomer. The loop has a cyclone, a sampling valve to collect particles and a 62.8mm internal diameter L-valve to recirculate the particles in the loop. A screw feeder with a rotation control system was used to feed the fuel mixture to the reactor. The operational conditions were monitored by pressure taps and thermocouples installed along the loop. A data acquisition system showed the main operational conditions to control. Experimental tests performed put in evidence the problems found during bed operation, with special attention to the solids feed device, to the L-valve operation, to particle size, solids inventory, fluidized gas velocity, fuel mixture and recirculated solids feeding positions.

Ramírez Behainne, Jhon Jairo; Hory, Rogério Ishikawa; Goldstein, Leonardo; Bernárdez Pécora, Araí Augusta

156

Fuel-Nitrogen Evolution During Fluidized Bed Oxy-Coal Combustion  

NASA Astrophysics Data System (ADS)

FTIR, thermo-gravimetric analysis techniques and molecular modelling were employed to study the effect of CO2 on fuel-nitrogen evolution under oxy-combustion conditions. The main objective is to compare NOx emissions at several molar fractions of O2 using Ar or CO2 as balance gas in a fluidized bed reactor. A char with about 16% N content was prepared by pyrolysis of polyacrylonitrile. This sample facilitated NOx evolution experiments due to the abundance of nitrogen complexes, and aided the identification and quantification of several N species by means ofFTIR. Results indicate that the presence of CO2 enhances NO2 formation. A complementary study was carried out by molecular modelling of the experimental reactions using the Gaussian 03 package. Different heterogeneous and homogeneous interactions between CO2 and char N-species were simulated. The results thus obtained show that the presence of CO2 during combustion can facilitate NCO formation which is a very reactive intermediate species that can be readily oxidized in the gaseous phase.

Sanchez, Astrid; Mondragon, Fanor; Eddings, Eric G.

157

Pressurized fluidized bed Combustion technology  

Microsoft Academic Search

The technology of pressurized fluidized bed combustion (PFBC), particularly in its application to a coal-burning combinedcycle (CC) plant, is evaluated in this book. Engineering systems analyses are performed for advanced concept plant components-boiler systems, including combustors, air-handling and air-injection equipment, and heat exchangers; solids handling, injection and ejection systems; hot-gas cleanup equipment; instrumentation and control systems; and turbines-and materials of

W. F. etc. Podolski; R. L. etc. Graves

1983-01-01

158

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY  

SciTech Connect

The Pennsylvania State University, under contract to the U.S. Department of Energy, National Energy Technology Laboratory is performing a feasibility analysis on installing a state-of-the-art circulating fluidized bed boiler and ceramic filter emission control device at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring multiple biofuels and coal-based feedstocks. The objective of the project is being accomplished using a team that includes personnel from Penn State's Energy Institute, Office of Physical Plant, and College of Agricultural Sciences, Foster Wheeler Energy Services, Inc., Parsons Energy and Chemicals Group, Inc., and Cofiring Alternatives. During this reporting period, work focused on completing the biofuel characterization and the design of the conceptual fluidized bed system.

Bruce G. Miller; Sharon Falcone Miller; Robert Cooper; Douglas Donovan; John Gaudlip; Matthew Lapinsky; William Serencsits; Neil Raskin; Dale Lamke

2001-07-13

159

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY  

SciTech Connect

The Pennsylvania State University, under contract to the U.S. Department of Energy, National Energy Technology Laboratory is performing a feasibility analysis on installing a state-of-the-art circulating fluidized bed boiler and ceramic filter emission control device at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring multiple biofuels and coal-based feedstocks. The objective of the project is being accomplished using a team that includes personnel from Penn State's Energy Institute, Office of Physical Plant, and College of Agricultural Sciences; Foster Wheeler Energy Services, Inc.; Parsons Energy and Chemicals Group, Inc.; and Cofiring Alternatives. During this reporting period, work focused on performing the design of the conceptual fluidized bed system and determining the system economics.

Bruce G. Miller; Sharon Falcone Miller; Robert Cooper; Douglas Donovan; John Gaudlip; Matthew Lapinsky; William Serencsits

2001-01-18

160

Corrosion in atmospheric fluidized bed combustors—The reactions of CaSO4 with Cr, Ni, Co, Fe, and several alloys  

NASA Astrophysics Data System (ADS)

When coal is burned in the presence of limestone in an atmospheric fluidized-bed combustor (AFBC), the sulfur emission can be kept below acceptable EPA levels. Calcining of the limestone produces CaO, which then forms solid CaSO4 by a reaction with the SO2 produced during coal combustion. The internal components ( e.g., heat exchanger tubes) of the bed, however, become coated with a compact layer of CaSO4, CaO, and ash during combustion. It has been suggested that the presence of the sulfate on these hot metal surfaces is the cause of observed instances of accelerated oxidation-sulfidation. This paper presents results which support the above suggestion. The reactions between Cr, Ni, Co, Fe, alloy 800, 2.25 Cr-1 Mo, 9 Cr-1 Mo steels, or 304 stainless steel with CaSO4 were studied using differential thermal and thermogravimetric analyses. The reaction products were analyzed using X-ray diffraction, optical microscopy, and in some instances, X-ray energy dispersive analyses. The chromium-calcium sulfate reaction is the only case studied in which a sulfide is not formed. In that case, CaCr2O4 is the reaction product. In all other cases, the reactions are oxidation-sulfidation processes.

Ficalora, P. J.

1983-11-01

161

Treatment of chromic tannery wastes using coal ashes from fluidized bed combustion of coal  

SciTech Connect

A new method of treatment for chromic tannery wastes containing chrome and large amounts organic substances has been investigated. It has been found that the addition of certain types of coal ash from fluid bed combustion technologies, at a suitable temperature and pH, results in effective removal of Cr(III) compounds present in the wastes. The wastes could then be subjected to further processing in conventional biological treatment units. The method is very simple, cheap, and effective and could be used for chromic tannery wastes of different compositions.

Bulewicz, E.M.; Kozak, A.; Kowalski, Z. [Cracow Univ. of Technology (Poland). Inst. of Inorganic Chemistry and Technology

1997-10-01

162

Emission characteristics of co-combustion of sewage sludge with olive cake and lignite coal in a circulating fluidized bed.  

PubMed

In this study, a circulating fluidized bed (CFB) of 125 mm diameter and 1800mm height was used to find the combustion characteristics of sewage sludge (SS) produced in Turkey. Sludge + olive cake, and sludge + lignite coal mixtures were burned separately. Various sludge-to-lignite coal and sludge-to-olive cake ratios (5/95, 10/90, 15/85, 20/80) were tried. On-line concentrations of major components (O2, SO2, CO2, CO, NOx, CmHn) were measured in the flue gas, as well as temperature and pressure distributions along the bed. Combustion efficiencies of sludge + olive cake and sludge + lignite coal mixtures were calculated, and the optimum conditions for operating parameters were discussed. The results have shown that the combustion mainly takes place in the upper regions of the main column where the temperature reaches 900 degrees C. SS + Coal burn in the CFB with an efficiency of 95.14% to 96.18%, which is considered to be quite good. When burning sludge mixed with olive cake, appreciable amounts of CO and unburned hydrocarbons are formed and the combustion efficiency drops to 92.93%. CO and CmHn emissions are lower when lignite coal is mixed with various amounts of SS than the emissions when the coal is burned alone. As the %SS is increased in the fuel mixture, the SO2 emission decreases. NOx emissions are slightly higher. When burning sludge mixed with olive cake, SO2 and NOx emissions are slightly higher. CO and CmHn emissions decrease sharply when SS is mixed with 5%wt. olive cake. With increasing sludge ratio these emissions increase due to the unburned hydrocarbons. As a result of this study, it is believed that SS can be burned effectively in a CFBC together with other fuels, especially with olive cake (OC). OC will be a good additive fuel for the combustion of lower quality fuels. PMID:15137713

Toraman, Oner Yusuf; Topal, Hüseyin; Bayat, Oktay; Atimtay, Aysel T

2004-01-01

163

Pilot-scale fluidized-bed combustor testing cofiring animal-tissue biomass with coal as a carcass disposal option  

SciTech Connect

This study was performed to demonstrate the technical viability of cofiring animal-tissue biomass (ATB) in a coal-fired fluidized-bed combustor (FBC) as an option for disposing of specified risk materials (SRMs) and carcasses. The purpose of this study was to assess the technical issues of feeding/combusting ATB and not to investigate prion deactivation/pathogen destruction. Overall, the project successfully demonstrated that carcasses and SRMs can be cofired with coal in a bubbling FBC. Feeding ATB into the FBC did, however, present several challenges. Specifically, handling/feeding issues resulting from the small scale of the equipment and the extremely heterogeneous nature of the ATB were encountered during the testing. Feeder modifications and an overbed firing system were necessary. Through statistical analysis, it was shown that the ATB feed location had a greater effect on CO emissions, which were used as an indication of combustion performance, than the fuel type due to the feeding difficulties. Baseline coal tests and tests cofiring ATB into the bed were statistically indistinguishable. Fuel feeding issues would not be expected at the full scale since full-scale units routinely handle low-quality fuels. In a full-scale unit, the disproportionate ratio of feed line size to unit diameter would be eliminated thereby eliminating feed slugging. Also, the ATB would either be injected into the bed, thereby ensuring uniform mixing and complete combustion, or be injected directly above the bed with overfire air ports used to ensure complete combustion. Therefore, it is anticipated that a demonstration at the full scale, which is the next activity in demonstrating this concept, should be successful. As the statistical analysis shows, emissions cofiring ATB with coal would be expected to be similar to that when firing coal only. 14 refs., 5 figs., 6 tabs.

Bruce G. Miller; Sharon Falcone Miller; Elizabeth M. Fedorowicz; David W. Harlan; Linda A. Detwiler; Michelle L. Rossman [Pennsylvania State University, University Park, PA (United States). Energy Institute

2006-10-15

164

Parametric performance studies on fluidized-bed heat exchangers  

Microsoft Academic Search

The performance of single and multistage shallow fluidized beds for possible application to the recovery of heat from sources as waste heat, and coal combustion or coal gasification were investigated. The following tests are investigated: (1) the effects of fouling due to liquid condensate in the gas stream of fluidized beds which are staged using baffle plates; and (3) the

R. C. Stoffler

1981-01-01

165

Parametric performance studies on fluidized-bed heat exchangers  

Microsoft Academic Search

The performance of single and multistage shallow fluidized beds is investigated for possible application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. Tests are conducted to (1) investigate the effects of fouling due to liquid condensate in the gas stream on fluidized bed heat exchanger performance, (2) investigate the performance of

R. C. Stoeffler

1982-01-01

166

Numerical Simulation on Hydrodynamics and Combustion in a Circulating Fluidized Bed under O2/CO2 and Air Atmospheres  

NASA Astrophysics Data System (ADS)

Oxy-fuel circulating fluidized bed (CFB) combustion technology is in the stage of initial development for carbon capture and storage (CCS). Numerical simulation is helpful to better understanding the combustion process and will be significant for CFB scale-up. In this paper, a computational fluid dynamics (CFD) model was employed to simulate the hydrodynamics of gas-solid flow in a CFB riser based on the Eulerian-Granular multiphase model. The cold model predicted the main features of the complex gas-solid flow, including the cluster formation of the solid phase along the walls, the flow structure of up-flow in the core and downward flow in the annular region. Furthermore, coal devolatilization, char combustion and heat transfer were considered by coupling semi-empirical sub-models with CFD model to establish a comprehensive model. The gas compositions and temperature profiles were predicted and the outflow gas fractions are validated with the experimental data in air combustion. With the experimentally validated model being applied, the concentration and temperature distributions in O2/CO2 combustion were predicted. The model is useful for the further development of a comprehensive model including more sub-models, such as pollutant emissions, and better understanding the combustion process in furnace.

Zhou, W.; Zhao, C. S.; Duan, L. B.; Qu, C. R.; Lu, J. Y.; Chen, X. P.

167

Fluidized bed combustor and tube construction therefor  

DOEpatents

A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

De Feo, Angelo (Passaic, NJ); Hosek, William (Morris, NJ)

1981-01-01

168

Tube construction for fluidized bed combustor  

DOEpatents

A fluidized bed combustor comprises a reactor or a housing which has a windbox distributor plate adjacent the lower end thereof which contains a multiplicity of hole and air discharge nozzles for discharging air and coal into a fluidized bed which is maintained above the distributor plate and below a take-off connection or flue to a cyclone separator in which some of the products of combustion are treated to remove the dust which is returned into the fluidized bed. A windbox is spaced below the fluidized bed and it has a plurality of tubes passing therethrough with the passage of combustion air and fluidizing air which passes through an air space so that fluidizing air is discharged into the reaction chamber fluidized bed at the bottom thereof to maintain the bed in a fluidized condition. A fluid, such as air, is passed through the tubes which extend through the windbox and provide a preheating of the combustion air and into an annular space between telescoped inner and outer tubes which comprise heat exchanger tubes or cooling tubes which extend upwardly through the distributor plate into the fluidized bed. The heat exchanger tubes are advantageously arranged so that they may be exposed in groups within the reactor in a cluster which is arranged within holding rings.

De Feo, Angelo (Totowa, NJ); Hosek, William (Mt. Tabor, NJ)

1984-01-01

169

Development of alterations in hamster distal lung following exposure to fly ash from fluidized bed coal combustion: a morphometric study.  

PubMed

Fly ash (30 mg) from an experimental fluidized bed coal combustor (FBC) was intratracheally instilled once into male Syrian golden hamsters. At 1, 3, 6, 9, or 30 days postadministration, lungs were fixed by intratracheal perfusion and tissues were processed for light and electron microscopic evaluation. Standard point count morphometry, used to analyze distal lung structures, revealed: an increase in volume density (Vv) of noncellular interstitial space at Day 1 which remained elevated at Day 3 but returned to control values subsequently; increased Vv for polymorphonuclear leukocytes (PMNs) and alveolar macrophages in alveolar air space at Day 6; increased Vv of cellular interstitium at Day 9; and increased Vv of noncellular interstitium at Day 30 following exposure. These observations are consistent with the hypothesis that the primary response of the distal lung to particle exposure is recruitment of PMNs and macrophages. When activated, these cells may release substances affecting the cellular and noncellular composition of the interstitial space, leading eventually to increased connective tissue in the interstitium. PMID:3945937

Lantz, R C; Hinton, D E

1986-01-01

170

Utilization of blended fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash in geopolymer.  

PubMed

In this paper, synthesis of geopolymer from fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash was studied in order to effectively utilize both ashes. FBC-fly ash and bottom ash were inter-ground to three different finenesses. The ashes were mixed with as-received PCC-fly ash in various proportions and used as source material for synthesis of geopolymer. Sodium silicate (Na(2)SiO(3)) and 10M sodium hydroxide (NaOH) solutions at mass ratio of Na(2)SiO(3)/NaOH of 1.5 and curing temperature of 65 degrees C for 48h were used for making geopolymer. X-ray diffraction (XRD), scanning electron microscopy (SEM), degree of reaction, and thermal gravimetric analysis (TGA) were performed on the geopolymer pastes. Compressive strength was also tested on geopolymer mortars. The results show that high strength geopolymer mortars of 35.0-44.0MPa can be produced using mixture of ground FBC ash and as-received PCC-fly ash. Fine FBC ash is more reactive and results in higher degree of reaction and higher strength geopolymer as compared to the use of coarser FBC ash. Grinding increases reactivity of ash by means of increasing surface area and the amount of reactive phase of the ash. In addition, the packing effect due to fine particles also contributed to increase in strength of geopolymers. PMID:19854038

Chindaprasirt, Prinya; Rattanasak, Ubolluk

2009-10-23

171

Co-firing of oil sludge with coal-water slurry in an industrial internal circulating fluidized bed boiler.  

PubMed

Incineration has been proven to be an alternative for disposal of sludge with its unique characteristics to minimize the volume and recover energy. In this paper, a new fluidized bed (FB) incineration system for treating oil sludge is presented. Co-firing of oil sludge with coal-water slurry (CWS) was investigated in the new incineration system to study combustion characteristics, gaseous pollutant emissions and ash management. The study results show the co-firing of oil sludge with CWS in FB has good operating characteristic. CWS as an auxiliary fuel can flexibly control the dense bed temperatures by adjusting its feeding rate. All emissions met the local environmental requirements. The CO emission was less than 1 ppm or essentially zero; the emissions of SO(2) and NO(x) were 120-220 and 120-160 mg/Nm(3), respectively. The heavy metal analyses of the bottom ash and the fly ash by ICP/AES show that the combustion ashes could be recycled as soil for farming. PMID:19249155

Liu, Jianguo; Jiang, Xiumin; Zhou, Lingsheng; Wang, Hui; Han, Xiangxin

2009-01-24

172

Utilization of blended fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash in geopolymer  

SciTech Connect

In this paper, synthesis of geopolymer from fluidized bed combustion (FBC) ash and pulverized coal combustion (PCC) fly ash was studied in order to effectively utilize both ashes. FBC-fly ash and bottom ash were inter-ground to three different finenesses. The ashes were mixed with as-received PCC-fly ash in various proportions and used as source material for synthesis of geopolymer. Sodium silicate (Na{sub 2}SiO{sub 3}) and 10 M sodium hydroxide (NaOH) solutions at mass ratio of Na{sub 2}SiO{sub 3}/NaOH of 1.5 and curing temperature of 65 deg. C for 48 h were used for making geopolymer. X-ray diffraction (XRD), scanning electron microscopy (SEM), degree of reaction, and thermal gravimetric analysis (TGA) were performed on the geopolymer pastes. Compressive strength was also tested on geopolymer mortars. The results show that high strength geopolymer mortars of 35.0-44.0 MPa can be produced using mixture of ground FBC ash and as-received PCC-fly ash. Fine FBC ash is more reactive and results in higher degree of reaction and higher strength geopolymer as compared to the use of coarser FBC ash. Grinding increases reactivity of ash by means of increasing surface area and the amount of reactive phase of the ash. In addition, the packing effect due to fine particles also contributed to increase in strength of geopolymers.

Chindaprasirt, Prinya [Department of Civil Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen 40002 (Thailand); Rattanasak, Ubolluk, E-mail: ubolluk@buu.ac.t [Department of Chemistry and Center for Innovation in Chemistry, Faculty of Science, Burapha University, Chonburi 20131 (Thailand)

2010-04-15

173

Fluidized bed combustion method  

SciTech Connect

A process is described for fluidized bed combustion of particulate combustible material in a furnace comprising feeding the particulate combustible material to the furnace and imparting a turbulent fluidized bed motion to the particulate combustible material within the furnace through the use of a vibrating screen. The screen is connected to means for vibrating the screen as the principal source of energy for imparting the turbulent fluidizing motion to the combustible material. This feeds combustion air to the fluidized bed of combustible material, discharging products of combustion from the furnace, and causing the fluidized bed to move in substantially horizontal direction so that combustible material is conveyed from the location of feed to the furnace through a combustion stage in the furnace to the location of discharge as combustible products.

Love, R.E.

1986-12-16

174

Experimental results of combustion and desulfurization in fluidized bed. Implementation opportunities.  

National Technical Information Service (NTIS)

Possibilities of both stationary fluidized bed combustion (SFBC) and circulating fluidized bed combustion (CFBC) technologies for desulfurization of Romanian coal-fired power plants have been studied since the 70's. The results of research on a 2 MWh SFBC...

L. Dragos G. Jinescu N. Scarlat

1996-01-01

175

New approach to understanding NO emission during bubbling fluidized bed coal combustion: separation of NO formation and reduction processes in the bed  

SciTech Connect

A new approach for separately evaluating NO formation and NO reduction during coal combustion in a fluidized bed was investigated. Sixteen different coals were burned in a laboratory-scale bubbling fluidized bed combustor with three different char loadings, which were established by changing the inlet oxygen concentrations. NO conversion ratios (X{sub NO} = the ratio of the mass of N atoms in the emitted NO to the mass of N atoms in the coal) were determined for the coals, and then 'ultimate NO conversion ratios' (X{sub NO}*) were obtained by extrapolation of the lines describing the dependence of X{sub NO} on O{sub 2} consumption rate to an O{sub 2} consumption rate of zero. The X{sub NO}* values correspond to the values that would be obtained for a single coal particle burning in the absence of char particles. Using this technique, the contribution of char particles to NO reduction was evaluated. The X{sub NO}* values depended on the N content and the O/N molar ratio of the coals. The bed temperature dependences of the sensitivity values (the slopes of the lines describing the dependence of X{sub NO} on O{sub 2} consumption rate), which include the contribution of NO reduction by char particles, differed substantially for the different coals. However, char loading had no clear effect on N{sub 2}O emission. This result suggests that the reduction by the char particles involves the competitive reaction of NO and N{sub 2}O, and the effect of the N{sub 2}O reduction by burning char particles was less than NO reduction. Our results indicate the importance of taking into account the effects of NO reduction by char particles on overall NOx emissions during fluidized bed combustion of coal. 19 refs., 14 figs., 2 tabs.

Takahiro Murakami; Yoshizo Suzuki [National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki (Japan)

2009-04-15

176

Chemical and toxicological characterization of organic constituents in fluidized-bed and pulverized coal combustion: a topical report  

SciTech Connect

Coal combustion fly ash from both conventional pulverized coal combustion (PCC) and fluidized-bed combustion (FBC) have been characterized as to their organic constituents and microbial mutagenic activity. The PCC fly ash was collected from a commercial utility generating plant using a low sulfur coal. The FBC fly ash was from a bench-scale developmental unit at the Grand Forks Energy Technology Center. Bulk samples of each fly ash were extracted using benzene/methanol and further separated using high performance liquid chromatography (HPLC). Subfractions from the HPLC separation were analyzed by gas chromatography using both element-specific nitrogen-phosphorus detectors and flame ionization detectors. Microbial mutagenicity assay results indicated that the crude organic extracts were mutagenic, and that both the specific activity and the overall activity of the PCC material was greater than that of the FBC material. Comparison of results from assays using S. typhimurium, TA1538NR indicated that nitrated polycyclic aromatic compounds (PAC) were responsible for much of the mutagenic activity of the PCC material. Similar results were obtained for assays of the FBC organic extract with standard and nitroreductase-deficient strains of S. typhimurium, TA100 and TA1538. Mutagenically active HPLC fractions were analyzed using high resolution gas chromatography (HRGC) and GC mass spectrometry (GC/MS), as well as probe inlet low and high resolutions MS. The discovery and identification of nitrated, oxygenated PAC are important because the presence of both nitro and/or keto functionalities on certain PAC has been shown to confer or enhance mutagenic activity.

Chess, E.K.; Later, D.W.; Wilson, B.W.; Harris, W.R.; Remsen, J.F.

1984-04-01

177

Alternative fuel firing in an atmospheric fluidized-bed combustion boiler. Final report. [Also with other waste fuels  

SciTech Connect

In 1981, Northern States Power Company converted its 15 MW French Island Unit No. 2 from a stoker-fired boiler to an atomspheric fluidized bed combustor designed to burn wood waste. A joint project between Northern States Power and the Electric Power Research Institute was subsequently established to determine the impact on operations, performance, and emissions of cofiring a variety of low-grade waste fuels with wood waste in this unit. Alternate waste fuels fired were shredded rubber tires, shredded railroad ties, refuse derived fuel, Minnesota peat, and sewage sludge. Each fuel was cofired with wood waste under steady boiler conditions for 50 to 100 hours. Results from the initial alternate fuel tests showed incomplete combustion of the fluidized bed combustor. To correct this problem the overfire air system was modified to improve mixing in the furnace volume above the fluidized bed. After the overfire air system was modified, the fluidized bed combustor proved able to burn all waste fuels effectively, except rubber tires which were not re-tested. Fuel handling problems were encountered with refuse derived fuel, peat and sewage sludge, but did not prevent their successful firing. Fluidized bed contamination was experienced with steel wire from rubber tires and stones and steel pieces from railroad ties. Also, the particulate scrubber was overloaded when firing high ash fuels such as rubber tires and peat. 2 refs., 21 figs., 32 tabs.

Miraglio, A.; Tegen, P.

1985-06-01

178

Life-cycle costs and economic feasibility of the atmospheric fluidized-bed combustion power plants  

Microsoft Academic Search

Coal-fired power plants produce the largest share of electric power generated in the US. Since coal is plentiful and relatively cheaper than gas or oil. The incentive to use coal is great. Increased state and federal environmental regulations and licensing requirements have caused an increase in construction costs for these plants. These facilities, in order to comply with the regulations,

Holstein

1984-01-01

179

Composition and chemistry of particulates from the Tidd Clean Coal Demonstration Plant pressurized fluidized bed combustor, cyclone, and filter vessel  

SciTech Connect

In a Pressurized Fluidized Bed Combustion (PFBC)/cyclone/filter system ground coal and sorbent are injected as pastes into the PFBC bed; the hot gases and entrained fine particles of ash and calcined or reacted sorbent are passed through a cyclone (which removes the larger entrained particles); and the very-fine particles that remain are then filtered out, so that the cleaned hot gas can be sent through a non-ruggedized hot-gas turbine. The 70 MWe Tidd PFBC Demonstration Plant in Brilliant, Ohio was completed in late 1990. The initial design utilized seven strings of primary and secondary cyclones to remove 98% of the particulate matter. However, the Plant also included a pressurized filter vessel, placed between the primary and secondary cyclones of one of the seven strings. Coal and dolomitic limestone (i.e, SO{sub 2} sorbent) of various nominal sizes ranging from 12 to 18 mesh were injected into the combustor operating at about 10 atm pressure and 925{degree}C. The cyclone removed elutriated particles larger than about 0.025 mm, and particles larger than ca. 0.0005 mm were filtered at about 750{degree}C by ceramic candle filters. Thus, the chemical reaction times and temperatures, masses of material, particle-size distributions, and chemical compositions were substantially different for particulates removed from the bed drain, the cyclone drain, and the filter unit. Accordingly, we have measured the particle-size distributions and concentrations of calcium, magnesium, sulfur, silicon, and aluminum for material taken from the three units, and also determined the chemical formulas and predominant crystalline forms of the calcium and magnesium sulfate compounds formed. The latter information is particularly novel for the filter-cake material, from which we isolated the ``new`` compound Mg{sub 2}Ca(SO{sub 4}){sub 3}.

Smith, D.H.; Grimm, U.; Haddad, G.

1995-12-31

180

APPLICATION OF ADVANCED TECHNOLOGY FOR NOX CONTROL: ALTERNATE FUELS AND FLUIDIZED-BED COAL COMBUSTION  

EPA Science Inventory

The paper discusses the effect of alternate fuels and fluidized coal combustion in controlling the emission of nitrogen oxides (NOx). The current trend in energy use in the U.S. is toward greater use of coal and coal derived fuels, and on ensuring that these fuels are produced an...

181

Pressurized fluidized bed coal combustion exposure testing of gas turbine and heat exchanger materials  

Microsoft Academic Search

The Exxon Research pressurized fludized bed (PFB) coal combustion facility, known as the miniplant, was constructed to demonstrate the feasibility of this coal combustion technique for environmentally acceptable energy production. This facility has been in operation since 1974, and has operated for 2500 test hours, during which over 600,000 lb of 2-4% sulfur coal were combusted in beds of limestone

M. S. Nutkis

1979-01-01

182

Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system. Second quarter progress report FY-1983, January 1-March 31, 1983  

SciTech Connect

The overall objective of the Westinghouse coal gasification program is to demonstrate the viability of the Westinghouse pressurized, fluidized bed, gasification system for the production of medium-Btu fuel gas for syngas, electrical power generation, chemical feedstocks, or industrial fuels and to obtain performance and scaleup data for the process and hardware. Accomplishments for the quarter are presented for the following tasks: (1) process development unit test operations and results; (2) process analysis; (3) cold flow scaleup facility; (4) process and component engineering and design; and (5) laboratory support studies of gas-solids flow modeling and coal/ash behavior. 8 figures, 11 tables.

Not Available

1983-05-16

183

Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system. First quarter progress report FY-1984, October 1-December 31, 1983  

SciTech Connect

The overall objective of the Westinghouse coal gasification program is to demonstrate the viability of the Westinghouse pressurized, fluidized bed, gasification system for the production of medium-Btu fuel gas for syngas, electrical power generation, chemical feedstocks, or industrial fuels and to obtain performance and scaleup data for the process and hardware. Progress reports are presented for the following tasks: (1) operation and maintenance of the process development unit (PDU); (2) process and component engineering and design; (3) cold flow scaleup facility (CFSF); (4) process analysis; and (5) laboratory support studies of gas-solids flow modeling and coal/ash behavior. 15 figs., 13 tabs.

Not Available

1984-07-25

184

Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system. Quarterly progress report, October 1-December 31, 1982  

SciTech Connect

The overall objective of the Westinghouse coal gasification program is to demonstrate the viability of the Westinghouse pressurized, fluidized bed, gasification system for the production of medium-Btu fuel gas for syngas, electrical power generation, chemical feedstocks, or industrial fuels and to obtain performance and scaleup data for the process and hardware. Progress reports are presented for the following tasks: (1) operation and maintenance of the process development unit (PDU); (2) process analysis; (3) cold flow scaleup facility; (4) process component engineering and design; and (5) laboratory support studies involving gas solids flow modeling and coal/ash behavior. 9 figures, 19 tables.

Not Available

1983-04-21

185

Two-dimensional model for circulating fluidized-bed reactors  

Microsoft Academic Search

Circulating fluidized bed reactors are widely used for the combustion of coal in power stations as well as for the cracking of heavy oil in the petroleum industry. A two-dimensional reactor model for circulating fluidized beds (CFB) was studied based on the assumption that at every location within the riser, a descending dense phase and a rising lean phase coexist.

H. Schoenfelder; M. Kruse; J. Werther

1996-01-01

186

Modeling the Combustion of Coal in a 300MW Circulating Fluidized Bed Boiler with Aspen Plus  

Microsoft Academic Search

A process model was proposed to predict the combustion of coal in a 300 MW CFB boiler. The effects of coal feed flow rate, the temperature of preheated air and air flow rate on the exhaust gas temperature were analyzed. The result showed that the exhaust gas temperature and boiler efficiency was consistent with data from literature.

Zhihui DONG Changqing DONG; Changqing Dong; Junjiao Zhang; Yongping Yang

2010-01-01

187

Operation of the Westinghouse fluidized bed devolatilizer with a variety of coal feedstocks  

Microsoft Academic Search

Under ERDA sponsorship, Westinghouse is conducting a program to develop a low-Btu coal gasification, combined-cycle, electrical power generating process. The program includes work in gas turbine combustor development, studies of turbine tolerance to erosive and corrosive fuel, gas cleaning and coal gasification process development. As part of the gasification work, Westinghouse is operating a process development unit (PDU) at Waltz

P. J. Margaritis; S. S. Kim; P. Cherish; L. A. Salvador

1977-01-01

188

The O{sub 2}-enriched air gasification of coal, plastics and wood in a fluidized bed reactor  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer The effect of the O{sub 2} in the gasification stream of a BFB gasifier has been studied. Black-Right-Pointing-Pointer Main advantage of the O{sub 2}-enriched air is the increasing of the bed temperature. Black-Right-Pointing-Pointer No remarkable effects on tar reduction. Decreasing of recognized PAHs. Black-Right-Pointing-Pointer Gasification reactions completed inside the dense bed and splashing zone. Black-Right-Pointing-Pointer Polycondensation reactions occur mainly in the freeboard region. - Abstract: 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.

Mastellone, Maria Laura, E-mail: mlaura.mastellone@unina2.it [Department of Environmental Sciences-Second University of Naples, Via Vivaldi, 43 81100 Caserta (Italy); Zaccariello, Lucio; Santoro, Donato; Arena, Umberto [Department of Environmental Sciences-Second University of Naples, Via Vivaldi, 43 81100 Caserta (Italy)

2012-04-15

189

Tennessee Valley Authority Atmospheric Fluidized-Bed Combustor Simulation Interim Annual Report, January 1-December 31, 1980.  

National Technical Information Service (NTIS)

A detailed description of the work performed during 1980 for the Tennessee Valley Authority (TVA) in support of the TVA Fluidized-Bed Combustion (FBC) Demonstration Plant Program is presented. The work was carried out under Task 4, modeling and simulation...

J. W. Wells M. H. Culver R. P. Krishnan

1981-01-01

190

Pulsed atmospheric fluidized bed combustion. Technical progress report, January 1, 1993--March 31, 1993  

SciTech Connect

As reported in previous quarterly reports, the fabrication of the fluid bed vessel, hot cyclone, coal handling system components, and coal/limestone feed systems is underway. Procurement of long lead time items was initiated in October 1992, and.deliveries are being made on schedule. In this quarterly period the following design tasks were accomplished. Mass and energy balance review and optimization; system operation calibrations; piping pressure drop design calculations; and pipe sizing and layout drawings.

Not Available

1993-05-01

191

DEM-LES of coal combustion in a bubbling fluidized bed. Part I: gas-particle turbulent flow structure  

Microsoft Academic Search

The gas and particle motions in a bubbling fluidized bed both with and without chemical reactions are numerically simulated. The solid phase is modelled as Discrete Element Method (DEM) and the gas phase is modelled as 2-D Navier–Stokes equations for 2-phase flow with fluid turbulence calculated by large Eddy simulation (LES), in which the effect of particles on subgrid scale

Haosheng Zhou; Gilles Flamant; Daniel Gauthier

2004-01-01

192

Modeling of fluidized-bed combustion of coal. Volume III. AFBC\\/PFBC system models manual. Final report  

Microsoft Academic Search

The purpose of this manual is to describe how to access and use MIT's Fluidized Bed Combustor (FBC) System Program. Presently, the FBC program is stored in a Honeywell Computer System and can be accessed using the Multics interactive system. This manual answers questions that may arise regarding the mechanics of operating the system program, as well as warns of

J. F. Louis; S. E. Tung

1982-01-01

193

Characterization of fly ashes from circulating fluidized bed combustion (CFBC) boilers cofiring coal and petroleum coke  

Microsoft Academic Search

The chemistry, mineralogy, morphology, and particle size distribution were investigated in fly ashes from the burning of Datong (ShanXi, China) bituminous coal and the cofiring of Mideast high-sulfur petroleum coke (PC) with 30:70 (cal %) and 50:50 (cal %) blends of Datong bituminous coal in two commercial CFBC boilers. With the exception of CaO, the amounts of major oxides in

Feihu Li; Jianping Zhai; Xiaoru Fu; Guanghong Sheng

2006-01-01

194

Staged fluidized bed  

DOEpatents

The invention relates to oil shale retorting and more particularly to staged fluidized bed oil shale retorting. Method and apparatus are disclosed for narrowing the distribution of residence times of any size particle and equalizing the residence times of large and small particles in fluidized beds. Particles are moved up one fluidized column and down a second fluidized column with the relative heights selected to equalize residence times of large and small particles. Additional pairs of columns are staged to narrow the distribution of residence times and provide complete processing of the material.

Mallon, R.G.

1983-05-13

195

Characterization of fly ashes from circulating fluidized bed combustion (CFBC) boilers cofiring coal and petroleum coke  

SciTech Connect

The chemistry, mineralogy, morphology, and particle size distribution were investigated in fly ashes from the burning of Datong (ShanXi, China) bituminous coal and the cofiring of Mideast high-sulfur petroleum coke (PC) with 30:70 (cal %) and 50:50 (cal %) blends of Datong bituminous coal in two commercial CFBC boilers. With the exception of CaO, the amounts of major oxides in the fly ashes from cofiring PC and coal were close to those of the common coal fly ashes. The PC-coal fly ashes were enriched in Ni, V, and Mo, implying these trace elements were mainly derived from PC. Ni and V, along with several other elements, such as Cr, Cu, Se, Pb, U, Th, and possibly As and Cd, increased in content with a decrease in temperature of the electrostatic precipitator (ESP). The results of chemistry, mineralogy, and morphology studies suggested that the desulfurization rate of the CFBC boilers at current conditions was low, and the PC tends to coarsen the fly ash particles and increase the loss on ignition (LOI) values, making these fly ashes unsuitable for use as a cement additive or a mineral admixture in concrete. Further studies on the combustion status of the CFBC boilers are needed if we want to be able to increase the desulfurization rate and produce high-quality fly ashes for broader and full utilization. 22 refs., 4 figs., 4 tabs.

Feihu Li; Jianping Zhai; Xiaoru Fu; Guanghong Sheng [Nanjing University, Nanjing (China). State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment

2006-08-15

196

Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system. Third quarter progress report FY-1983, April 1-June 30, 1983  

SciTech Connect

The overall objective of the Westinghouse coal gasification program is to demonstrate the viability of the Westinghouse pressurized, fluidized bed, gasification system for the production of medium-Btu fuel gas for syngas, electrical power generation, chemical feedstocks, or industrial fuels and to obtain performance and scaleup data for the process and hardware. Accomplishments for the past quarter are presented for the following tasks: process development unit test operations; process analysis; process and component engineering and design; cold flow scaleup facility; and laboratory support studies. 3 refs., 33 figs., 11 tabs.

Not Available

1983-09-07

197

Impact of the addition of chicken litter on mercury speciation and emissions from coal combustion in a laboratory-scale fluidized bed combustor  

SciTech Connect

Co-combustion of chicken litter with coal was performed in a laboratory-scale fluidized bed combustor to investigate the effect of chicken litter addition on the partitioning behavior of mercury. Gaseous total and elemental mercury concentrations in the flue gas were measured online, and ash was analyzed for particle-bound mercury along with other elemental and surface properties. The mercury mass balance was between 85 and 105%. The experimental results show that co-combustion of chicken litter decreases the amount of elemental and total mercury in the gas phase. Mercury content in fly ash increases with an increasing chicken litter share. 22 refs., 6 figs., 5 tabs.

Songgeng Li; Shuang Deng; Andy Wu; Wei-ping Pan [Western Kentucky University, Bowling Green, KY (United States). Institute for Combustion Science and Environmental Technology

2008-07-15

198

Coal-fired CFB, kiln heat-recovery cut costs, pollution. [Circulating fluidized bed  

SciTech Connect

California Portland Cement Co. is installing a circulating fluidised-bed boiler (the largest in the US), two heat-recovery steam generators for the cement kiln exhaust, and two turbine/generators to supply power to the plant, in an energy self-sufficiency project. The company has its own coal mine and limestone quarry.

Makansi, J.

1985-05-01

199

Trace metal capture by various sorbents during fluidized bed coal combustion  

Microsoft Academic Search

Toxic trace metallic elements such as arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, mercury, nickel, and selenium are usually contained in coal in various forms and trace amounts. These metals will either stay in the ash or be vaporized during high temperature combustion. Portions of the vaporized metals may eventually be emitted from a combustion system in the form of

T. C. Ho; A. N. Ghebremeskel; J. R. Hopper

1996-01-01

200

Hydrodynamics of fluidized beds using image analysis  

NASA Astrophysics Data System (ADS)

Fluidized beds, originally developed in the 1920s, have become the reactors of choice in several industrial processes. For example, coal combustion within fluidized bed systems has improved efficiency over other combustion technologies. There are however, several issues related to this technology that remain to be resolved. Three of the more significant issues are the dynamics of equal-density particle segregation and the influence of horizontal tube banks on both bubble hydrodynamics and solids mixing. These topics were investigated through the use of video image analysis of thin transparent fluidized beds. Experimental data, obtained from bubbling beds with and without simulated horizontal heat exchanger tubes, were used to evaluate existing hydrodynamic models and derive new semi-empirical models.

Hull, Ashley Samuel

201

Energy recovery from fluidized-bed combustion  

SciTech Connect

Fluidized-bed processing was developed and commercialized during the late 1930s and early 40s on coal gasification and metallurgical applications in Germany, and for the catalytic cracking of heavy oils to produce high-octane gasoline in the U.S. The technique has since found wide acceptance around the world in a variety of metallurgical, chemical and environmental control applications, Table 1. A significant development is the increasing application of fluidized-bed combustion for the utilization of waste materials and low-grade fuels as alternative energy sources. Because of its unique ability to handle a wide variety of liquids and solids as fuels in an energy-efficient and environmentally acceptable manner, fluidized-bed combustion is ideally suited to many applications. A simple approach may be used to analyze the energy balance when considering alternatives.

Sneyd, R.J.

1984-01-01

202

Particle withdrawal from fluidized bed systems  

SciTech Connect

Method and apparatus are disclosed for removing ash formed within, and accumulated at the lower portion of, a fluidized bed coal gasification reactor vessel. A supplemental fluidizing gas, at a temperature substantially less than the average fluidized bed combustion operating temperature, is injected into the vessel and upwardly through the ash so as to form a discrete thermal interface region between the fluidized bed and the ash. The elevation of the interface region, which rises with ash accumulation, is monitored by a thermocouple and interrelated with a motor controlled outlet valve. When the interface rises above the temperature indicator, the valve opens to allow removal of some of the ash, and the valve is closed, or positioned at a minimum setting, when the interface drops to an elevation below that of the thermocouple.

Andermann, R.E.; Rath, L.K.; Salvador, L.A.

1982-01-05

203

Burning waste with FBC. [Fluidized Bed Combustion  

SciTech Connect

This article examines fluidized bed combustion as a method of choice for disposing for waste economically and within the bounds of rigid environmental standards. The topics discussed in the article include technology scaleup, wood and fossil wastes, municipal and hospital wastes, fuel flexibility, and a sidebar on the fluidized bed combustion technology. The waste fuels of major interest are various low grade liquid and solid residues from the coal, oil, forest products and automotive industries, as well as post-harvest biomass and municipal refuse.

Salaff, S.

1991-11-01

204

State of the art of pressurized fluidized bed combustion systems  

SciTech Connect

This report was prepared at the request of the Tennessee Valley Authority (TVA) to clarify the development status of the pressurized fluidized bed combustor (PFBC) and to place in perspective the problems which are yet to be solved before commercialization of the concept is practical. This report, in essence, supersedes the interim report published in 1979, Assessment of the State of the Art of Pressurized Fluidized Bed Combustion Systems. A brief overview of the PFBC concept is included citing potential advantages and disadvantages relative to atmospheric fluidized bed combustion (AFBC) and conventional pulverized coal plants. A survey of existing and developing PFBC experimental facilities is presented in some detail which includes the major accomplishments at the respective facilities. Recent data on plant emissions, turbine/gas cleanup systems, and overall efficiency are provided. Findings of several design studies are also discussed. The results of recent gas turbine and cascade tests have been encouraging although the full assessment of the accomplishments have not been made. The delay in construction of the Grimethorpe plant causes further delay in proof-testing full-size, rotating turbomachinery. Several parameters are recommended for further assessment in design studies including: (1) effect of turbine life on cost of power; and (2) effect of reduced gas turbine inlet temperature and pressure on cost of power.

Graves, R.L.

1980-09-01

205

Fluid dynamics of a fluidized bed packed with heat exchangers  

NASA Astrophysics Data System (ADS)

Tests of two fluidized bed facilities are described. Bed dynamics of a one foot gas fired fluidized bed (GFFB) and its interrelation with the heat transfer characteristics of immersed heat exchangers of different configurations were studied. The GFFB, capable of achieving different gas velocity distributions in the bed with the help of a specially designed gas distributor, was operated to gain useful information on the influence of various operating parameters, such as the superficial gas velocity and its profile, the bed temperature and pressure, and settled bed height, on the bed expansion and heat transfer characteristics of vertica and horizontal tube bundles, and an inverted U-tube. Tests were also performed on an inverted U-tube with longitudinal fins, and two unfinned inverted U-tubes to study the effect of heat exchanger solidity. Particle attrition studies were also performed at atmospheric pressure. A one-foot, coal-fired fluidized bed was also built and initial tests were performed. Typical heat transfer and particle attrition data were collected with a single vertical tube heat exchanger axially located in the bed. The behavior of deep and shallow beds, as observed in the GFFB, was confirmed.

Zakkay, V.; Miller, G.; Kolar, A.; Franceschi, J.; Panunzio, S.; Skelley, W.; Ho, C. C.; Brentan, A.; Kiviat, G.; Rosen, S.

1981-04-01

206

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY  

SciTech Connect

The Pennsylvania State University, under contract to the U.S. Department of Energy (DOE), National Energy Technology Laboratory (NETL) is performing a feasibility analysis on installing a state-of-the-art circulating fluidized bed (CFB) boiler and ceramic filter emission control device at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring multiple biofuels and coal-based feedstocks. Penn State currently operates an aging stoker-fired steam plant at its University Park campus and has spent considerable resources over the last ten to fifteen years investigating boiler replacements and performing life extension studies. This effort, in combination with a variety of agricultural and other wastes generated at the agricultural-based university and the surrounding rural community, has led Penn State to assemble a team of fluidized bed and cofiring experts to assess the feasibility of installing a CFB boiler for cofiring biomass and other wastes along with coal-based fuels. The objective of the project is being accomplished using a team that includes personnel from Penn State's Energy Institute and the Office of Physical Plant, Foster Wheeler Energy Services, Inc., and Cofiring Alternatives.

Bruce G. Miller; Sharon Falcone Miller; Robert Cooper; Douglas Donovan; John Gaudlip; Matthew Lapinsky; William Serencsits; Neil Raskin; Dale Lamke; Joseph J. Battista

2001-03-31

207

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY  

SciTech Connect

The Pennsylvania State University, under contract to the U.S. Department of Energy (DOE), National Energy Technology Laboratory (NETL) is performing a feasibility analysis on installing a state-of-the-art circulating fluidized bed (CFB) boiler and ceramic filter emission control device at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring multiple biofuels and coal-based feedstocks. Penn State currently operates an aging stoker-fired steam plant at its University Park campus and has spent considerable resources over the last ten to fifteen years investigating boiler replacements and performing life extension studies. This effort, in combination with a variety of agricultural and other wastes generated at the agricultural-based university and the surrounding rural community, has led Penn State to assemble a team of fluidized bed and cofiring experts to assess the feasibility of installing a CFB boiler for cofiring biomass and other wastes along with coal-based fuels.

Bruce G. Miller; Sharon Falcone Miller; Robert Cooper; Douglas Donovan; John Gaudlip; Matthew Lapinsky; William Serencsits; Neil Raskin; Dale Lamke

2001-10-12

208

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY  

SciTech Connect

The Pennsylvania State University, under contract to the U.S. Department of Energy (DOE), National Energy Technology Laboratory (NETL) is performing a feasibility analysis on installing a state-of-the-art circulating fluidized bed (CFB) boiler and ceramic filter emission control device at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring multiple biofuels and coal-based feedstocks. Penn State currently operates an aging stoker-fired steam plant at its University Park campus and has spent considerable resources over the last ten to fifteen years investigating boiler replacements and performing life extension studies. This effort, in combination with a variety of agricultural and other wastes generated at the agricultural-based university and the surrounding rural community, has led Penn State to assemble a team of fluidized bed and cofiring experts to assess the feasibility of installing a CFB boiler for cofiring biomass and other wastes along with coal-based fuels. The objective of the project is being accomplished using a team that includes personnel from Penn State's Energy Institute, Office of Physical Plant, and College of Agricultural Sciences; Foster Wheeler Energy Services, Inc.; Parsons Energy and Chemicals Group, Inc.; and Cofiring Alternatives.

Bruce G. Miller; Sharon Falcone Miller; Robert Cooper; Douglas Donovan; John Gaudlip; Matthew Lapinsky; William Serencsits; Neil Raskin; Tom Steitz

2002-07-12

209

Fluidized bed silicon deposition  

Microsoft Academic Search

The growth of silicon on seed particles from the pyrolysis of silane in a fluidized bed reactor (FBR) was studied. The grown particles were shown to be crystalline and to have a structure which has been interpreted to indicate growth by chemical vapor deposition as well as by the collection (scavenging) of silicon clusters on seed particle surfaces. Scanning electron

G. Hsu; A. Morrison; N. Rohatgi; R. Lutwack; T. MacConnell

1984-01-01

210

MULTISTAGE FLUIDIZED BED REACTOR  

DOEpatents

A multistage fluidized bed reactor is described in which each of a number of stages is arranged with respect to an associated baffle so that a fluidizing gas flows upward and a granular solid downward through the stages and baffles, whereas the granular solid stopsflowing downward when the flow of fluidizing gas is shut off.

Jonke, A.A.; Graae, J.E.A.; Levitz, N.M.

1959-11-01

211

Engineer, design, construct, test and evaluate a pressurized fluidized bed pilot plant using high sulfur coal for production of electric power. Phase I. Preliminary engineering. Topical report, 1 March 1976-1 June 1977  

Microsoft Academic Search

A promising approach for clean, cost-competitive, electric power generation from coal with improved power cycle efficiency involves the application of a pressurized fluidized bed (PFB) combustor to a combined cycle. Based on a conceptual design of a 500 MW base load power station, a configuration for a pilot electric plant was selected which will use high sulfur (> 31%) coal

S. Moskowitz; R. Cole; A. Defeo

1977-01-01

212

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY  

SciTech Connect

The Pennsylvania State University, utilizing funds furnished by the U.S. Department of Energy's Biomass Power Program, investigated the installation of a state-of-the-art circulating fluidized bed boiler at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring biofuels and coal-based feedstocks. The study was performed using a team that included personnel from Penn State's Energy Institute, Office of Physical Plant, and College of Agricultural Sciences; Foster Wheeler Energy Services, Inc.; Foster Wheeler Energy Corporation; Parsons Energy and Chemicals Group, Inc.; and Cofiring Alternatives. The activities included assessing potential feedstocks at the University Park campus and surrounding region with an emphasis on biomass materials, collecting and analyzing potential feedstocks, assessing agglomeration, deposition, and corrosion tendencies, identifying the optimum location for the boiler system through an internal site selection process, performing a three circulating fluidized bed (CFB) boiler design and a 15-year boiler plant transition plan, determining the costs associated with installing the boiler system, developing a preliminary test program, determining the associated costs for the test program, and exploring potential emissions credits when using the biomass CFB boiler.

Bruce G. Miller; Sharon Falcone Miller; Robert Cooper; John Gaudlip; Matthew Lapinsky; Rhett McLaren; William Serencsits; Neil Raskin; Tom Steitz; Joseph J. Battista

2003-03-26

213

Parametric performance studies on fluidized-bed heat exchangers  

NASA Astrophysics Data System (ADS)

The performance of single and multistage shallow fluidized beds for possible application to the recovery of heat from sources as waste heat, and coal combustion or coal gasification were investigated. The following tests are investigated: (1) the effects of fouling due to liquid condensate in the gas stream of fluidized beds which are staged using baffle plates; and (3) the effects of different heat exchanger surface geometries. The conditions fouling by a liquid condensate are selected. Modifications are made to the fluidized bed heat exchanger facility for the fouling experiments.

Stoffler, R. C.

1981-10-01

214

Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system. Fourth quarter progress report, July 1-September 30, 1982  

SciTech Connect

The overall objective of the Westinghouse coal gasification program is to demonstrate the viability of the Westinghouse pressurized, fluidized bed, gasification system for the production of medium-Btu fuel gas for syngas, electrical power generation, chemical feedstocks, or industrial fuels and to obtain performance and scaleup data for the process and hardware. Technical progress summaries and reports are presented for the following tasks: (1) process development unit (PDU) test operations and results (gasifier test TP-033-1 and maintenance and modifications); (2) process analysis (environmental characterization results, coal gas combustion results, and fines elutriation and consumption results); (3) cold flow scaleup (modifications and maintenance, operations, and data analysis); (4) process and component engineering and design (hot fines recycle modifications, and hot recycled fines); (5) laboratory support studies (gas-solids flow modeling and coal/ash behavior). 23 figures, 23 tables.

Not Available

1983-02-17

215

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY  

SciTech Connect

The Pennsylvania State University, under contract to the US Department of Energy, National Energy Technology Laboratory is performing a feasibility analysis on installing a state-of-the-art circulating fluidized bed boiler and ceramic filter emission control device at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal or coal refuse, and developing a test program to evaluate cofiring multiple biofuels and coal-based feedstocks. The objective of the project is being accomplished using a team that includes personnel from Penn State's Energy Institute and the Office of Physical Plant, Foster Wheeler Energy Corporation, Foster Wheeler Development Corporation, and Cofiring Alternatives. The major emphasis of work during this reporting period was to assess the types and quantities of potential feedstocks and collect samples of them for analysis. Approximately twenty different biomass, animal waste, and other wastes were collected and analyzed.

Bruce G. Miller; Curtis Jawdy

2000-10-09

216

Fluidized bed retorting of tar sands  

Microsoft Academic Search

Raw tar sand is treated in a fluidized bed reactor means wherein the raw tar sands are fed into an area below the top of the bed. The bitumen is converted in the process in a reducing atmosphere including steam to produce hot coked sand and hot off-gases. Off-gases from the reactor means pass through a heat exchanger means to

P. H. II

1978-01-01

217

Use of fluidized bed combustion by-products for liners and alkali substitutes. Technical report, March 1May 31, 1995  

Microsoft Academic Search

Fluidized Bed Combustion of coal eliminates most emissions of S and N oxides but produces sizable volumes of a solid residue that EPA may require to be placed in capped and lined landfills. Fluidized Bed Combustors are one of the most promising growth markets for Illinois coal and imposing cap and liner requirements may make the technology uneconomic. Fluidized Bed

B. C. Paul; S. Esling; F. Pisani; T. Wells

1995-01-01

218

Study of parameters influencing metal wastage in fluidized bed combustors.  

National Technical Information Service (NTIS)

Fluidized bed combustion (FBC) technology is a means of burning high-sulfur coal and various other feedstocks in an efficient, cost-effective, and environmentally acceptable manner. Unfortunately, the wearing or wastage of metal heat exchanger tubes in bu...

W. F. Podolski R. Lyczkowski E. Montrone J. Drennen Y. H. Ai

1991-01-01

219

Fluidized bed combustion  

SciTech Connect

The invention relates to fluidized bed combustors that might tilt in use so that the depth of the bed progressively changes across its width. Air is supplied from two or more sources and means are provided to vary the flow from the sources as the bed tilts so that the air supplied to the portion of the bed of increased depth is increased relatively to the air supplied to the portion of the bed of lesser depth.

Hodgkin, A.F.

1980-12-16

220

Hot corrosion\\/erosion testing of materials for application to advanced power conversion systems using coal-derived fuels. Task II: fluidized bed combustion. Third task report, July 1September 30, 1978  

Microsoft Academic Search

The second and third segments of a 1000 hour exposure test of potential gas turbine and boiler tube materials for use in Pressurized Fluidized Bed Coal Combustion were successfully completed. This brought the total exposure time to 565 hours on the gas turbine specimens and 682 hours on the heat exchanger specimens. The 100 hour test (Run 79) had to

M. S. Nutkis; R. R. Bertrand; M. Ernst; R. C. Hoke; M. D. Loughnane; V. J. Siminski

1979-01-01

221

Task II: Evaluation of Heat-Exchanger and Turbine Materials for Use in a Coal-Fired Fluidized-Bed-Combustion Environment. Final Report, July 1, 1976-July 31, 1980.  

National Technical Information Service (NTIS)

Specific alloys were tested as in-bed and above-bed heat exchanger materials in the fireside environment of a pressurized fluidized bed coal combustor (PFBCC). Corrosion conditions on the alloys exposed to normal and very low oxygen pressures in the prese...

1981-01-01

222

FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY  

SciTech Connect

The Pennsylvania State University, under contract to the U.S. Department of Energy, National Energy Technology Laboratory is performing a feasibility analysis on installing a state-of-the-art circulating fluidized bed boiler and ceramic filter emission control device at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring multiple biofuels and coal-based feedstocks. The objective of the project is being accomplished using a team that includes personnel from Penn State's Energy Institute, Office of Physical Plant, and College of Agricultural Sciences; Foster Wheeler Energy Services, Inc.; Parsons Energy and Chemicals Group, Inc.; and Cofiring Alternatives. During this reporting period, the final technical design and cost estimate were submitted to Penn State by Foster Wheeler. In addition, Penn State initiated the internal site selection process to finalize the site for the boiler plant.

Bruce G. Miller; Sharon Falcone Miller; Robert Cooper; Douglas Donovan; John Gaudlip; Matthew Lapinsky; William Serencsits; Neil Raskin; Tom Steitz

2002-10-14

223

Industrial pressurized fluidized-bed combustors, 1992  

Microsoft Academic Search

Coal-fired Pressurized Fluidized-Bed Combustion (PFBC) systems offer the advantages of high efficiency removal of sulfur during combustion, and inherently low NOâ emissions; advantages which support the National Energy Strategy (NES). The Morgantown Energy Technology Center (METC) of the US Department of Energy (DOE) has recently completed studies of coal-fired PFBC in an industrial setting. In addition to in-house studies, interest

D. Bonk; T. Hand; M. Freier

1992-01-01

224

Industrial pressurized fluidized-bed combustors, 1992  

Microsoft Academic Search

This paper discusses coal-fired Pressurized Fluidized-Bed Combustion (PFBC) systems which offer the advantages of high efficiency, removal of sulfur during combustion, and inherently low NOâ emissions; advantages which support the National Energy Strategy (NES). The Morgantown Energy Technology Center (METC) of the U.S. Department of Energy (DOE) has recently completed studies of coal-fired PFBC in an industrial setting. In addition

D. L. Bonk; Hand T. J; M. Freier

1992-01-01

225

Proceedings - Fourth annual fluidized bed conference  

SciTech Connect

The proceedings contain 14 papers which deal with the following topics: anthracite culm combustion for process heat and cogeneration; case histories describing the performance of circulating fluidized bed combustors (CFBC); design and economics of CFBC; pulverizers for coal and sorbent preparation; ash removal systems; and the status of independent power generation and the Clean Coal Technology Program. Appendices contain manufacturers' installation lists with details of customers, fuels, steam conditions, and applications. All papers have been processed separately for inclusion on the data base.

Not Available

1991-01-01

226

Mercury emissions during cofiring of sub-bituminous coal and biomass (chicken waste, wood, coffee residue, and tobacco stalk) in a laboratory-scale fluidized bed combustor  

SciTech Connect

Four types of biomass (chicken waste, wood pellets, coffee residue, and tobacco stalks) were cofired at 30 wt % with a U.S. sub-bituminous coal (Powder River Basin Coal) in a laboratory-scale fluidized bed combustor. A cyclone, followed by a quartz filter, was used for fly ash removal during tests. The temperatures of the cyclone and filter were controlled at 250 and 150{sup o}C, respectively. Mercury speciation and emissions during cofiring were investigated using a semicontinuous mercury monitor, which was certified using ASTM standard Ontario Hydra Method. Test results indicated mercury emissions were strongly correlative to the gaseous chlorine concentrations, but not necessarily correlative to the chlorine contents in cofiring fuels. Mercury emissions could be reduced by 35% during firing of sub-bituminous coal using only a quartz filter. Cofiring high-chlorine fuel, such as chicken waste (Cl = 22340 wppm), could largely reduce mercury emissions by over 80%. When low-chlorine biomass, such as wood pellets (Cl = 132 wppm) and coffee residue (Cl = 134 wppm), is cofired, mercury emissions could only be reduced by about 50%. Cofiring tobacco stalks with higher chlorine content (Cl = 4237 wppm) did not significantly reduce mercury emissions. Gaseous speciated mercury in flue gas after a quartz filter indicated the occurrence of about 50% of total gaseous mercury to be the elemental mercury for cofiring chicken waste, but occurrence of above 90% of the elemental mercury for all other cases. Both the higher content of alkali metal oxides or alkali earth metal oxides in tested biomass and the occurrence of temperatures lower than 650{sup o}C in the upper part of the fluidized bed combustor seemed to be responsible for the reduction of gaseous chlorine and, consequently, limited mercury emissions reduction during cofiring. 36 refs., 3 figs. 1 tab.

Yan Cao; Hongcang Zhou; Junjie Fan; Houyin Zhao; Tuo Zhou; Pauline Hack; Chia-Chun Chan; Jian-Chang Liou; Wei-ping Pan [Western Kentucky University (WKU), Bowling Green, KY (USA). Institute for Combustion Science and Environmental Technology (ICSET)

2008-12-15

227

Multicycle study on chemical-looping combustion of simulated coal gas with a CaSO{sub 4} oxygen carrier in a fluidized bed reactor  

SciTech Connect

The cyclic test of a CaSO{sub 4}-based oxygen carrier (natural anhydrite) in alternating reducing simulated coal gas and oxidizing conditions was performed at 950{degree}C in a fluidized bed reactor at atmospheric pressure. A high concentration of CO{sub 2} was obtained in the reduction. The H{sub 2} and CO conversions and CO{sub 2} yield increased initially and final decreased significantly. The release of SO{sub 2} and H{sub 2}S during the cyclic test was found to be responsible for the decrease of reactivity of a CaSO{sub 4} oxygen carrier. The oxygen carrier conversion after the reduction reaction decreased gradually in the cyclic test. Through the comparison of mass-based reaction rates as a function of mass conversion at typical cycles, it was also evident that the reactivity of a CaSO{sub 4} oxygen carrier increased for the initial cycles but finally decreased after around 15 cycles. X-ray diffraction analysis revealed that the presence and intensity of the reduction sulfur species was in accordance with the results of gas conversion. The content of CaO was higher than expected, suggesting the formation of SO{sub 2} and H{sub 2}S during the cycles. Surface morphology analysis demonstrates that the natural anhydrite particle surface varied from impervious to porous after the cyclic test. It was also observed that the small grains on the surface of the oxygen carrier sintered in the cyclic tests. Energy-dispersive spectrum analysis also demonstrated the decrease of oxygen intensity after reduction, and CaO became the main component after the 20th oxidation. Pore structure analysis suggested that the particles agglomerated or sintered in the cyclic tests. The possible method for sulfur mitigation is proposed. Finally, some basic consideration on the design criteria of a CLC system for solid fuels using a CaSO{sub 4} oxygen carrier is discussed by the references and provides direction for future work. 49 refs., 10 figs., 5 tabs.

Qilei Song; Rui Xiao; Zhongyi Deng; Wenguang Zheng; Laihong Shen; Jun Xiao [Southeast University, Nanjing (China). Thermoenergy Engineering Research Institute

2008-11-15

228

Pulmonary toxicity associated with fly ash from fluidized bed coal combustion. II. Cellular morphometry of distal lung following a single intratracheal instillation.  

PubMed

Fly ash from an experimental fluidized bed coal combustor (FBC) was intratracheally instilled (once) into male Syrian golden hamsters at concentrations of 0 (control), 3, 10, 30, and 100 mg/animal. Thirty days postadministration, lungs were fixed by intratracheal perfusion, and tissues were processed for electron microscopic evaluation. Standard point count morphometry was used to analyze distal lung structures. Significant differences were found in volume density of noncellular interstitial space, with this compartment being increased in a dose-dependent manner. Volume density, numerical density, and average cellular volume of distal lung cells revealed no significant differences between treated and control animals. In addition, diffusion capacity and air-blood barrier thickness were not significantly altered in treated animals. The absence of cellular change at 30 days postexposure suggests a residual effect on noncellular interstitium, which may implicate fibrosis. PMID:6464021

Lantz, R C; Hinton, D E

1984-08-01

229

Biparticle fluidized bed reactor  

DOEpatents

A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

Scott, Charles D. (Oak Ridge, TN); Marasco, Joseph A. (Kingston, TN)

1995-01-01

230

Biparticle fluidized bed reactor  

DOEpatents

A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves.

Scott, Charles D. (Oak Ridge, TN); Marasco, Joseph A. (Kingston, TN)

1996-01-01

231

Biparticle fluidized bed reactor  

DOEpatents

A fluidized bed reactor system which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves.

Scott, Charles D. (Oak Ridge, TN)

1993-01-01

232

Biparticle fluidized bed reactor  

DOEpatents

A fluidized bed reactor system is described which utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary and tertiary particulate phases, continuously introduced and removed simultaneously in the cocurrent and countercurrent mode, act in a role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Means for introducing and removing the sorbent phases include feed screw mechanisms and multivane slurry valves. 3 figs.

Scott, C.D.; Marasco, J.A.

1996-02-27

233

Biparticle fluidized bed reactor  

DOEpatents

A fluidized bed reactor system utilizes a fluid phase, a retained fluidized primary particulate phase, and a migratory second particulate phase. The primary particulate phase is a particle such as a gel bead containing an immobilized biocatalyst. The secondary particulate phase, continuously introduced and removed in either cocurrent or countercurrent mode, acts in a secondary role such as a sorbent to continuously remove a product or by-product constituent from the fluid phase. Introduction and removal of the sorbent phase is accomplished through the use of feed screw mechanisms and multivane slurry valves. 3 figs.

Scott, C.D.; Marasco, J.A.

1995-04-25

234

Rotating fluidized bed heat exchanger  

Microsoft Academic Search

A rotating fluidized bed heat exchanger particularly adaptable as a heat exchange unit in the recuperator section of conventional gas turbine engines is disclosed comprising an annular fluidized bed, defined by inner and outer spaced apart coaxial cylindrical, perforated walls, which rotates about the longitudinal axis of the cylinders. The bed is comprised of pulverulent inert particulate material and includes

W. H. Belke; A. Goloff; G. B. Grim

1982-01-01

235

Predictive models for circulating fluidized bed combustors  

SciTech Connect

The overall objective of this investigation is to develop experimentally verified models for circulating fluidized bed (CFB) combustors. The purpose of these models is to help American industry, such as Combustion Engineering, design and scale-up CFB combustors that are capable of burning US Eastern high sulfur coals with low SO{sub x} and NO{sub x} emissions. In this report, presented as a technical paper, solids distributions and velocities were computed for a PYROFLOW circulating fluidized bed system. To illustrate the capability of the computer code an example of coal-pyrite separation is included, which was done earlier for a State of Illinois project. 24 refs., 20 figs., 2 tabs.

Gidaspow, D.

1989-11-01

236

Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system: Topical report, Process analysis, FY 1983  

SciTech Connect

KRW Energy Systems, Inc., is engaged in the continuing development of a pressurized, fluidized-bed gasification process at its Waltz Mill Site in Madison, Pennsylvania. The overall objective of the program is to demonstrate the viability of the KRW process for the environmentally-acceptable production of low- and medium-Btu fuel gas from a variety of fossilized carbonaceous feedstocks and industrial fuels. This report presents process analysis of the 24 ton-per-day Process Development Unit (PDU) operations and is a continuation of the process analysis work performed in 1980 and 1981. Included is work performed on PDU process data; gasification; char-ash separation; ash agglomeration; fines carryover, recycle, and consumption; deposit formation; materials; and environmental, health, and safety issues. 63 figs., 43 tabs.

None

1987-07-31

237

Engineering support services for the DOE/GRI coal-gasification research program. Technical and economic assessment of the Westinghouse fluidized-bed coal gasification process  

SciTech Connect

Kellogg was requested by DOE/GRI to perform a technical and economic assessment of the Westinghouse fluidized bed coal gasification process as applied to production of SNG equivalent to 250 billion BTU/day from Pittsburgh No. 8 coal. Based on operating experiences in the PDU, where most of the key variables have been demonstrated during 5+ years of testing, Westinghouse provided process data for the gasifier area. Kellogg selected the overall processing sequence and established design bases for the balance of the plant. This work was subsequent to a previous (1979) screening evaluation of Westinghouse by Kellogg: comparison of the two designs reveals the following: The 1980 gasifier design basis, while more detailed, is almost identical to that of 1979. The gas treatment and sulfur recovery schemes were significantly changed: Combined shift/methanation was substituted for stand-alone reaction units; independent Selexol units for removal of H/sub 2/S and CO/sub 2/ replaced a non-selective Benfield unit; and a Claus-SCOT combination replaced Stretford units and significantly improved the flue gas desulfurization. Key results of the current efforts are compared with those of the screening evaluation. The reductions in efficiencies in the new calculations are attributed to a more realistic evaluation of plant energy requirements and to lack of optimization of individual plant section designs. The economic data indicate that a noteworthy reduction in gas cost was accomplished by a reduction in the capital cost of the plant, such that Kellogg concludes, as previously for the screening evaluation, that the Westinghouse process appears to be superior to existing processes (i.e., Lurgi) and at least competitive with other processes evaluated under the DOE/GRI joint program.

Bostwick, L.E.; Hubbard, D.A.; Laramore, R.W.; Ethridge, T.R.

1981-04-01

238

Fluid dynamics of a fluidized bed packed with heat exchangers. Final report  

Microsoft Academic Search

Two fluidized bed facilities were built, and tests were conducted. Initially, a 1-ft. gas-fired fluidized bed (GFFB) was built as a predecessor to a coal-fired fluidized bed (CFFB) facility, in order to study the bed dynamics and its interrelation with the heat transfer characteristics of immersed heat exchangers of different configurations. The unique feature of the GFFB was the capability

V. Zakkay; G. Miller; A. Kolar

1981-01-01

239

Parametric performance studies on fluidized-bed heat exchangers. Task 1: Fouling characteristics  

Microsoft Academic Search

Analyses and experiments are being performed to investigate the heat transfer performance of single and multistage shallow fluidized beds for application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. Tests were conducted to investigate the effects of liquid condensate fouling on fluidized bed heat exchanger performance. Liquid condensates used in these

R. C. Stoeffler

1982-01-01

240

Evaluation of PCDD/Fs and metals emission from a circulating fluidized bed incinerator co-combusting sewage sludge with coal.  

PubMed

The emission characteristics of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and heavy metals were evaluated during co-combustion of sewage sludge with coal from a circulating fluidized bed incinerator. The stack gas, slag and fly ash samples were sampled and analyzed. The gas-cleaning system consisted of electrostatic precipitators and a semi-dry scrubber. Results showed that the stack gas and fly ash exhibited mean dioxin levels of 9.4 pg I-TEQ/Nm3 and 11.65 pg I-TEQ/g, respectively, and showed great similarities in congener profiles. By contrast, the slag presented a mean dioxin level of 0.15 pg I-TEQ/g and a remarkable difference in congener profiles compared with those of the stack gas and fly ash. Co-combusting sewage sludge with coal was able to reduce PCDD/Fs emissions significantly in comparison with sewage sludge mono-combustion. The leaching levels of Hg, Pb, Cd, Ni, Cr, Cu, and As in the fly ash and slag were much lower than the limits of the environmental protection standard in China. These suggest that the co-combustion of sewage sludge and coal is an advisable treatment method from an environmental perspective. PMID:23586319

Zhang, Gang; Hai, Jing; Cheng, Jiang; Cai, Zhiqi; Ren, Mingzhong; Zhang, Sukun; Zhang, Jieru

2013-01-01

241

Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system. Third quarter progress report FY-1984, April 1-June 30, 1984  

SciTech Connect

The overall objective of the KRW coal gasification program is to demonstrate the viability of the KRW pressurized, fluidized-bed, gasification system for the production of medium-Btu fuel gas for syngas, electrical power generation, chemical feedstocks, or industrial fuels and to obtain performance and scaleup data for the process and hardware. Progress reports are presented for the following tasks: (1) operation and maintenance of the process development unit (PDU); (2) modifications to the PDU; (3) cold flow scaleup facility; (4) advanced process design and analysis; and (5) laboratory support studies. For laboratory support studies, coal and/or char fines from Wyoming Sub C, Western Kentucky, Republic of South Africa (RSA), and Pittsburgh seam coals processed in the PDU were characterized for reactivity on a thermogravimetric analyzer. The average relative reactivity of the fines (-120 x +140 mesh) was found to be nearly the same as that for larger size distribution (18 x 60 mesh, -1.0 + 0.25 mm). This is consistent with the observations of studies reported in literature on carbon gasification reactions.

Not Available

1986-01-31

242

Emissions During Co-Firing of RDF-5 with Coal in a 22 t/h Steam Bubbling Fluidized Bed Boiler  

NASA Astrophysics Data System (ADS)

The co-firing of biomass and fossil fuel in the same power plant is one of the most important issues when promoting the utilization of renewable energy in the world. Recently, the co-firing of coal together with biomass fuel, such as "densified refuse derived fuel" (d-RDF or RDF-5) or RPF (refuse paper & plastic fuel) from waste, has been considered as an environmentally sound and economical approach to both waste remediation and energy production in the world. Because of itscomplex characteristics when compared to fossil fuel, potential problems, such as combustion system stability, the corrosion of heat transfer tubes, the qualities of the ash, and the emissionof pollutants, are major concerns when co-firing the biomass fuel with fossil fuel in a traditional boiler. In this study, co-firing of coal with RDF-5 was conducted in a 22t/h bubbling fluidized bed (BFB) steam boiler to investigate the feasibility of utilizing RDF-5 as a sustainable fuels in a commercial coal-fired steam BFB boiler. The properties of the fly ash, bottom ash, and the emission of pollutants are analyzed and discussed in this study.

Wan, Hou-Peng; Chen, Jia-Yuan; Juch, Ching-I.; Chang, Ying-Hsi; Lee, Hom-Ti

243

Feasibility study on solidification of municipal solid waste incinerator fly ash with circulating fluidized bed combustion coal fly ash.  

PubMed

The objective of this study was to assess the feasibility of solidification of municipal solid waste incinerator (MSWI) fly ash with circulation fluidized bed combustion (CFBC) fly ash, which is unsuitable as a cement replacement due to its high amounts of carbon, lime and anhydrite. The solidification process was conducted on samples prepared from MSWI fly ash, binders (cement clinkers and CFBC fly ash were mixed at two replacement ratios) and water (water/solid weight ratio = 0.4), among which the MSWI fly ash replaced each binder at the ratio of 0, 20, 40, 60 and 80% by dry weight. The samples were subjected to compressive strength tests and Toxicity Characteristic Leaching Procedure and the results showed that all solidified MSWI fly ash can meet the landfill standard imposed by US EPA after 28 days of curing. Micro-analysis (X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectrophotometry) revealed that the main hydrate products were C-S-H gel and ettringite, which have a positive effect on heavy metals retention. Therefore, this method provides a possibility to achieve a cheap and effective solution for MSWI fly ash management and use for CFBC fly ash. PMID:19423575

Liu, Wenshi; Hou, Haobo; Zhang, Chuhao; Zhang, Dajie

2009-05-07

244

Multifuel bubbling bed fluidized bed combustor system  

SciTech Connect

Apparatus for generating heat is described, comprising: a fluidized bed pyrolyzer; a fluidized bed combustor; a combustor vessel; means for supporting a combustor bed of granular material within the combustor vessel; means for adding the gaseous effluents removed from the pyrolyzer bed to the combustor bed; means for adding granular material to the combustor bed; means for removing gaseous effluents from the combustor vessel; means for removing bed material from the combustor; a heat exchanger comprising a vessel; means for adding gaseous effluents to, and means for removing gaseous effluents from, the heat exchanger vessel, and means for adding an exchange coolant to, and means for removing an exchange coolant from, the heat exchanger vessel; particulate collector means connected to the heat exchanger for removing particulate matter from the gaseous effluents removed from the heat exchanger; and stack means connected to the particulate collector for releasing the gaseous effluents removed from the heat exchanger to the atmosphere.

Wormer, A.F.

1989-04-25

245

Single-train demonstration plant to convert eastern bituminous coal to methane or electricity using ash-agglomerating, fluidized-bed gasification. Final topical report, June 1986October 1986  

Microsoft Academic Search

A first-pass screening design and rough-order-of-magnitude (ROM) cost estimate was prepared for a single-train demonstration plant to convert bituminous coal to methane and electricity using an ash-agglomerating, fluidized bed process. The total plant investment, with contingency and process development allowances, is estimated at $188 million (1986 dollars). If built separately, the methane plant is estimated to cost $136 million, and

Smelser

1986-01-01

246

Particle pressures in fluidized beds  

SciTech Connect

This is an experimental project to make detailed measurements of the particle pressures generated in fluidized beds. The focus lies in two principle areas: (1) the particle pressure distribution around single bubbles rising in a two-dimensional gas-fluidized bed and (2) the particle pressures measured in liquid-fluidized beds. This first year has largely been to constructing the experiments The design of the particle pressure probe has been improved and tested. A two-dimensional gas-fluidized bed has been constructed in order to measure the particle pressure generated around injected bubbles. The probe is also being adapted to work in a liquid fluidized bed. Finally, a two-dimensional liquid fluidized bed is also under construction. Preliminary measurements show that the majority of the particle pressures are generated in the wake of a bubble. However, the particle pressures generated in the liquid bed appear to be extremely small. Finally, while not directly associated with the particle pressure studies, some NERSC supercomputer time was granted alongside this project. This is being used to make large scale computer simulation of the flow of granular materials in hoppers.

Campbell, C.S.; Rahman, K.; Hu, X.; Jin, C.; Potapov, A.V.

1992-01-01

247

Pressurized fluidized bed reactor  

DOEpatents

A pressurized fluid bed reactor power plant includes a fluidized bed reactor contained within a pressure vessel with a pressurized gas volume between the reactor and the vessel. A first conduit supplies primary gas from the gas volume to the reactor, passing outside the pressure vessel and then returning through the pressure vessel to the reactor, and pressurized gas is supplied from a compressor through a second conduit to the gas volume. A third conduit, comprising a hot gas discharge, carries gases from the reactor, through a filter, and ultimately to a turbine. During normal operation of the plant, pressurized gas is withdrawn from the gas volume through the first conduit and introduced into the reactor at a substantially continuously controlled rate as the primary gas to the reactor. In response to an operational disturbance of the plant, the flow of gas in the first, second, and third conduits is terminated, and thereafter the pressure in the gas volume and in the reactor is substantially simultaneously reduced by opening pressure relief valves in the first and third conduits, and optionally by passing air directly from the second conduit to the turbine. 1 fig.

Isaksson, J.

1996-03-19

248

A comparative study of inputs and outputs of fluidized bed coal-fired boilers and pulverized coal-fired boilers  

SciTech Connect

The comparisons in this paper consider the physical inputs and outputs of the three types of combustors on the basis of burning one ton of fuel. The specific assumptions for the pulverized coal boiler technology are a 99 percent combustion efficiency and utilization of a wet limestone (CaCO/sub 3/) scrubbing system for removal of sulfur dioxide (SO/sub 2/) from the flue gas. The limestone scrubber will employ a raw limestone slurry fed at 40 percent solids by weight and will include dewatering of the scrubber sludge to 50 percent moisture by weight (dry basis). The AFBC will operate at 97 percent combustion efficiency; at 90 percent calcining of the limestone incident to the bed; have a 50/50 split of ash, unburned carbon, and inerts between flue gas and bed drawdown; and a 30/70 split of the calcium and sulfur compounds between the flue gas and bed drawdown system, respectively. The CFBC is assumed to have a combustion efficiency of 99 percent, 95 percent calcining of the limestone, and a 30/70 split of ash and inerts between flue gas and bed drawdown.

Hall, H.V.; Kadeg, R.

1983-11-01

249

Costs for advanced coal-combustion technologies. Final report  

Microsoft Academic Search

The report gives results of an evaluation of the development status of advanced coal combustion technologies and discusses the preparation of performance and economic models for their application to electric utility plants. The technologies addressed were atmospheric fluidized bed combustion (AFBC), pressurized fluidized bed combustion (PFBC), and integrated gasification combined cycle (IGCC). The development status was also reviewed for pulverized-coal-fired

J. A. Martinez; G. C. Snow; M. Maibodi

1990-01-01

250

Design of entrained-flow and moving-, packed-, and fluidized-bed sorption systems: Grain-model kinetics for hot coal-gas desulfurization with limestone  

SciTech Connect

Concentration profiles in several configurations of sorption systems (moving, packed, and fluidized beds and entrained-flow) were determined using the grain and the unreacted shrinking core model for the description of the gas-solid reaction kinetics. General equations for the design and analysis of all these reactor configurations are given, and simple analytical solutions are proposed. The behavior of these reactors can be expressed as a function of only four parameters: the size of the sorbent pellet and the Peclet, Sherwood (or Biot), and Damkoehler numbers. These general equations were then applied to the lime(stone)/H{sub 2}S systems. Using limestone particles with diameters on the order of 100 {mu}m for entrained-flow and with diameters on the order of 1 mm for the other configurations, it was found that H{sub 2}S could be removed from the hot coal gas to near its equilibrium value with more than 75% sorbent utilization and with reasonable bed depth (about 1 m, or 1-s contact time for entrained-flow) when the reactor temperature is maintained 25--50 C above the calcination temperature of the calcium carbonate.

Fenouil, L.A.; Lynn, S. [Lawrence Berkeley Lab., CA (United States). Dept. of Chemical Engineering

1996-04-01

251

A novel three phase fluidized bed process for simultaneous selective flocculation and microbial desulfurization of high sulfur coal  

Microsoft Academic Search

The purpose of this work was to investigate the feasibility of recovery and reclamation of ultrafine coal particles generated during the processing of coal. 10--35% of the total annual tonnage of coal in atypical coal preparation plant is estimated to be lost in forms of ultrafine particles during the mining, shipping, handling, and preparation of the coal. The technical feasibility

Liang-Shih Fan; F. Bavarian; Y. A. Attia; M. Elzeky

1990-01-01

252

A novel three phase fluidized bed process for simultaneous selective flocculation and microbial desulfurization of high sulfur coal. Final report  

Microsoft Academic Search

The purpose of this work was to investigate the feasibility of recovery and reclamation of ultrafine coal particles generated during the processing of coal. 10--35% of the total annual tonnage of coal in atypical coal preparation plant is estimated to be lost in forms of ultrafine particles during the mining, shipping, handling, and preparation of the coal. The technical feasibility

Liang-Shih Fan; F. Bavarian; Y. A. Attia; M. Elzeky

1990-01-01

253

Fluidized-bed copper oxide process. Proof-of-concept unit design  

SciTech Connect

The fluidized-bed copper oxide process was developed to simultaneously remove sulfur dioxide and nitrogen oxide contaminants from the flue gas of coal-fired utility boilers. This dry and regenerable process uses a copper oxide sorbent in a fluidized-bed reactor. Contaminants are removed without generating waste material. (VC)

Shah, P.P.; Takahashi, G.S.; Leshock, D.G.

1991-10-14

254

Description, applications and numerical modelling of bubbling fluidized bed combustion in waste-to-energy plants  

Microsoft Academic Search

The use of the fluidized bed combustor (FBC) has increased. It began in the 20th century as coal combustion and gasification, which then developed into catalytic reactions. Only recently, the application field has been extended to the incineration of biomass and pre-treated waste, for either power generation or waste disposal. The success of fluidized bed combustion is due to high

S. Ravelli; A. Perdichizzi; G. Barigozzi

2008-01-01

255

Abatement of NâO emissions from circulating fluidized bed combustion through afterburning  

Microsoft Academic Search

A method for the abatement of NâO emission from fluidized bed combustion has been investigated. The method consists of burning a secondary fuel after the normal circulating fluidized bed combustor. Liquefied petroleum gas (LPG), fuel oil, pulverized coal, and wood, as well as sawdust, were used as the secondary fuel. Experiments showed that the NâO emission can be reduced by

Lennart Gustavsson; Bo Leckner

1995-01-01

256

Refractory experience in circulating fluidized bed combustors, Task 7  

SciTech Connect

This report describes the results of an investigation into the status of the design and selection of refractory materials for coal-fueled circulating fluidized-bed combustors. The survey concentrated on operating units in the United States manufactured by six different boiler vendors: Babcock and Wilcox, Combustion Engineering, Foster Wheeler, Keeler Dorr-Oliver, Pyropower, and Riley Stoker. Information was obtained from the boiler vendors, refractory suppliers and installers, and the owners/operators of over forty units. This work is in support of DOE's Clean Coal Technology program, which includes circulating fluidized-bed technology as one of the selected concepts being evaluated.

Vincent, R.Q.

1989-11-01

257

Simulation of circulating fluidized bed reactors using ASPEN PLUS  

Microsoft Academic Search

A comprehensive model is developed for the combustion of coal in a circulating fluidized bed combustor (CFBC). The proposed model integrates hydrodynamic parameters, reaction model and kinetic subroutines necessary to simulate coal combustion in a CFBC. Kinetic expressions were developed for the char combustion rates and the SO2 absorption in the bed using data from the literature. The reaction model,

R. Sotudeh-Gharebaagh; R. Legros; J. Chaouki

1998-01-01

258

Electric utility second-generation pressurized fluidized bed combustion plants  

Microsoft Academic Search

In the search for a more efficient, less costly, and more environmentally responsible method for generating electrical power from coal, research and development has turned to advanced pressurized fluidized bed combustion (PFBC) and coal gasification technologies. A logical extension of this work is the second-generation PFBC plant, which incorporates key components of each of these technologies. In this new type

A. Robertson; D. Bonk

1992-01-01

259

Second-Generation Pressurized Fluidized Bed Combustion: Small gas turbine industrial plant study  

SciTech Connect

Second-Generation Pressurized Fluidized Bed Combustion (PFBC) plants provide a coal-fired, high-efficiency, combined-cycle system for the generation of electricity and steam. The plants use lime-based sorbents in PFB combustors to meet environmental air standards without back-end gas desulfurization equipment. The second-generation system is an improvement over earlier PFBC concepts because it can achieve gas temperatures of 2100{degrees}F and higher for improved cycle efficiency while maintaining the fluidized beds at 1600{degrees}F for enhanced sulfur capture and minimum alkali release. Second-generation PFBC systems are capable of supplying the electric and steam process needs of industrial plants. The basic second-generation system can be applied in different ways to meet a variety of process steam and electrical requirements. To evaluate the potential of these systems in the industrial market, conceptual designs have been developed for six second-generation PFBC plants. These plants cover a range of electrical outputs from 6.3 to 41.5 MWe and steam flows from 46,067 to 442,337 lb/h. Capital and operating costs have been estimated for these six plants and for equivalent (in size) conventional, coal-fired atmospheric fluidized bed combustion cogeneration plants. Economic analyses were conducted to compare the cost of steam for both the second-generation plants and the conventional plants.

Shenker, J.; Garland, R.; Horazak, D.; Seifert, F.; Wenglarz, R.

1992-07-01

260

Second-Generation Pressurized Fluidized Bed Combustion: Small gas turbine induustrial plant study  

SciTech Connect

Second-Generation Pressurized Fluidized Bed Combustion (PFBC) plants provide a coal-fired, high-efficiency, combined-cycle system for the generation of electricity and steam. The plants use lime-based sorbents in PFB combustors to meet environmental air standards without back-end gas desulfurization equipment. The second-generation system is an improvement over earlier PFBC concepts because it can achieve gas temperatures of 2100[degrees]F and higher for improved cycle efficiency while maintaining the fluidized beds at 1600[degrees]F for enhanced sulfur capture and minimum alkali release. Second-generation PFBC systems are capable of supplying the electric and steam process needs of industrial plants. The basic second-generation system can be applied in different ways to meet a variety of process steam and electrical requirements. To evaluate the potential of these systems in the industrial market, conceptual designs have been developed for six second-generation PFBC plants. These plants cover a range of electrical outputs from 6.3 to 41.5 MWe and steam flows from 46,067 to 442,337 lb/h. Capital and operating costs have been estimated for these six plants and for equivalent (in size) conventional, coal-fired atmospheric fluidized bed combustion cogeneration plants. Economic analyses were conducted to compare the cost of steam for both the second-generation plants and the conventional plants.

Shenker, J.; Garland, R.; Horazak, D.; Seifert, F.; Wenglarz, R.

1992-07-01

261

Consider nonfouling fluidized bed exchangers  

SciTech Connect

Applications for fluidized bed heat exchangers in various industries, their operating principles and a detailed analysis of their suitability for replacing double-pipe scraped-surface heat exchangers in lube oil plants are discussed. Development of the fluidized bed heat exchanger started in the early 70s and was totally dedicated to improvement of the multistage flash evaporator for sea water desalination. This resulted in a demonstration plant with a fluidized bed heat exchanger with a total heat transfer surface of over 1,000 m/sup 2/. Over an operating period of more than 15,000 hours untreated sea water was heated to more than 120{sup 0}C without any fouling in the tubes due to scale deposits.

Klaren, D.G.; Baiiie, R.E. (Scheffers of America, Inc., Indialantic, FL (US))

1989-07-01

262

Second-generation pressurized fluidized bed combustion  

SciTech Connect

Under the sponsorship of the United States Department of Energy, Foster Wheeler Corporation is developing second-generation pressurized fluidized bed combustion (PFBC) power plant technology that will enable this type of plant to operate with net plant efficiencies in the range of 43 to 46 percent (based on the higher heating value of the coal), with a reduction in the cost of electricity of at least 20 percent. A three-phase program is under way. Its scope encompasses the conceptual design of a commercial plant through the process of gathering needed experimental test data to obtain design parameters.

Wolowodiuk, W.; Robertson, A.

1992-05-01

263

Second-generation pressurized fluidized bed combustion  

SciTech Connect

Under the sponsorship of the United States Department of Energy, Foster Wheeler Corporation is developing second-generation pressurized fluidized bed combustion (PFBC) power plant technology that will enable this type of plant to operate with net plant efficiencies in the range of 43 to 46 percent (based on the higher heating value of the coal), with a reduction in the cost of electricity of at least 20 percent. A three-phase program is under way. Its scope encompasses the conceptual design of a commercial plant through the process of gathering needed experimental test data to obtain design parameters.

Wolowodiuk, W.; Robertson, A.

1992-01-01

264

Ninth annual fluidized bed conference  

SciTech Connect

Ten papers were presented at the Ninth Fluidized Bed Conference held in Bakersfield, CA on December 7-8, 1993. The papers covered such subjects as community relations, operational experience at the NISCO cogeneration facility, multiple stoker-field retrofit with fluidized bed combustion, influence of fuel properties, combustion of pulp and papermill sludges and biomass in bubbling fluidized boilers, diesel emissions control reactor power cycle, erosion-corrosion resistant coatings in CFBC systems, FBC's role in solid fuel firing, and the role for solid fuel firing in the Nation's energy future. A separate abstract was prepared for each paper for the Energy Data Base.

Not Available

1993-01-01

265

Effect of temperature on reduction of CaSO{sub 4} oxygen carrier in chemical-looping combustion of simulated coal gas in a fluidized bed reactor  

SciTech Connect

Chemical-looping combustion (CLC) is a promising combustion technology for gaseous and solid fuel with efficient use of energy and inherent separation of CO{sub 2}. The concept of a coal-fueled CLC system using, calcium sulfate (CaSO{sub 4}) as oxygen carrier is proposed in this study. Reduction tests of CaSO{sub 4} oxygen carrier with simulated coal gas were performed in a laboratory-scale fluidized bed reactor in the temperature range of 890-950{degree}C. A high concentration of CO{sub 2} was obtained at the initial reduction period. CaSO{sub 4} oxygen carrier exhibited high reactivity initially and decreased gradually at the late period of reduction. The sulfur release during the reduction of CaSO{sub 4} as oxygen carrier was also observed and analyzed. H{sub 2} and CO{sub 2} conversions were greatly influenced by reduction temperature. The oxygen carrier conversion and mass-based reaction rates during the reduction at typical temperatures were compared. Higher temperatures would enhance reaction rates and result in high conversion of oxygen carrier. An XRD patterns study indicated that CaS was the dominant product of reduction and the variation of relative intensity with temperature is in agreement with the solid conversion. ESEM analysis indicated that the surface structure of oxygen carrier particles changed significantly from impervious to porous after reduction. EDS analysis also demonstrated the transfer of oxygen from the oxygen carrier to the fuel gas and a certain amount of sulfur loss and CaO formation on the surface at higher temperatures. The reduction kinetics of CaSO{sub 4} oxygen carrier was explored with the shrinking unreacted-core model. The apparent kinetic parameters were obtained, and the kinetic equation well predicted the experimental data. Finally, some basic considerations on the use of CaSO{sub 4} oxygen carrier in a CLC system for solid fuels were discussed.

Song, Q.L.; Xiao, R.; Deng, Z.Y.; Shen, L.H.; Xiao, J.; Zhang, M.Y. [Southeast University, Nanjing (China)

2008-12-15

266

An investigation of the reactivity of chars formed in fluidized bed gasifiers: the effect of reaction conditions and particle size on coal char reactivity  

SciTech Connect

Coal-derived chars formed during air-blown gasification processes may rapidly lose reactivity, and this can limit the extent of their conversion. To study this effect, a laboratory-scale fluidized bed reactor has been modified to enable char samples to be prepared under strictly controlled conditions of temperature, pressure, particle size, gaseous environment, and residence time. This has been used to gain an insight into the deactivation of the chars as they form and during their subsequent residence time in the bed of the gasifier. The work shows that the char reactivity declines rapidly during its formation as part of the pyrolysis of the coal. This is thought to result from the rapid deposition of secondary, unreactive char within the pores of the material. In this work, it has been shown to occur within the initial 10 s in the reactor, but in reality, this effect probably occurred within 1 s. Temperature, pressure, and particle size have an impact on this process. Subsequently, and over a longer time scale, structural reorganization occurs in the solid char, and this anneals the structure by graphitization. This has been indicated by the identification of graphite, by X-ray diffraction in long-residence-time chars. The presence of steam in the fluidizing gas seemed to reduce the reactivity of small char particles, which could be due to the gasification of the more reactive parts. This effect does not seem to be present in data obtained with larger particles, and this is thought to be due to the greater influence of secondary char deposition in the larger particles. The reactivities of the largest particles formed over the longest time in this work are getting close to the reactivity values seen in char particles formed in a pilot-scale gasifier. 21 refs., 15 figs., 2 tabs.

A. Cousins; N. Paterson; D.R. Dugwell; R. Kandiyoti [Imperial College London, London (United Kingdom). Department of Chemical Engineering

2006-12-15

267

Application of pressurized circulating fluidized bed technology for combined cycle power generation  

Microsoft Academic Search

Ahlstrom Pyropower, Inc. (API) pioneered the development of atmospheric circulating fluidized bed (ACFB) technology. The sustained success with ACFB and continued research in ACFB systems has led Ahlstrom towards the development of pressurized circulating fluidized bed (PCFB) technology. Since the mid-1980s many components of the PCFB combined cycle power plant were developed. Based on the component development experience, a 10

Kumar M. Sellakumar; Thomas W. Lamar

1995-01-01

268

Comminution of limestone during batch fluidized-bed calcination and sulfation  

Microsoft Academic Search

Batchwise fluidized-bed calcination and sulfation of a limestone were done to investigate particle comminution phenomena and their relation with parallel occurrence of reactions. Operating conditions of the bed were those typical of atmospheric bubbling fluidized-bed combustors. A general framework of comminution phenomena is outlined, which includes different types of fragmentations as well as attrition by abrasion. Comminution processes were characterized

Fabrizio Scala; Antonio Cammarota; Riccardo Chirone; Piero Salatino

1997-01-01

269

Review of fluidized bed combustion technology in the United States  

SciTech Connect

The United States (US) initiated work in fluidized bed combustion (FBC) in the mid-1960s, with primary emphasis on industrial applications. With passage of the Clean Air Act in 1970, the environmental benefits of the technology soon attracted interest. This provided the impetus for expanded effort focused on the reduced NO/sub x/ emissions resulting from lower combustion temperature and SO/sub 2/ capture by means of chemical reaction with limestone or dolomite in the fluidized bed. The oil embargo in 1973 further stimulated interest in FBC technology. Several manufacturers presently offer atmospheric fluidized bed combustion (AFBC) and circulating fluidized bed combustion (CFBC) units for industrial application in the United States. However, FBC for electric power generation remains in the development and demonstration phase. The Tennessee Valley Authority (TVA) and Electric Power Research Institute (EPRI) are operating a 20-MW AFBC utility pilot plant and are proceeding with plans for a 160-MW(e) demonstration plant with other participants. Research has been under way on pressurized fluidized bed combustion (PFBC) at Grimethorpe in South Yorkshire, England, and within the United States at the Curtiss-Wright Pilot Plant, and at other smaller test facilities. An emerging turbocharged PFBC concept will likely stimulate more near-term interest in PFBC technology for both industrial and utility applications. The major US programs and test facilities are described; remaining technical uncertainties are discussed, and the future outlook for the technology is assessed.

Krishnan, R.P.; Daw, C.S.; Jones, J.E. Jr.

1984-01-01

270

Coal Pyrolysis by Hot Solids from a Fluidized Bed Computer. Quarterly Progress Report, March 1--May 31, 1978.  

National Technical Information Service (NTIS)

Experiments have been conducted using a mildly caking Texas lignite coal over a temperature range of 800 to 1600 exp 0 F, in the absence of dolomitic compounds and with a fluidizing gas velocity of 0.8 ft/sec. During these runs, the coal was fed continuou...

J. P. Longwell J. B. Howard W. A. Peters J. Y. Yeboah G. Alexander

1978-01-01

271

Co-combustion of coal and biomass in pulverized fuel and fluidized bed systems -- Activities and research in Europe  

Microsoft Academic Search

Biomass or sewage sludge utilized as additional fuel in coal combustion systems has consequences on combustion behavior, emissions, corrosion, and residual matter. Therefore, at the beginning of 1993 the European Union within the frame of the APAS program launched a project called ``Combined Combustion of Biomass\\/Sewage Sludge and Coal''. Within this project, the effects of burning sewage sludge and agricultural

K. R. G. Hein; H. Spliethoff

1999-01-01

272

Fluidized bed nuclear fission reactor  

Microsoft Academic Search

For the further development of nuclear fission reactors, the feasibility of a new concept is evaluated. It concerns a fluidized bed reactor in which carbon particles with a uranium core are fluidized and cooled by a high velocity pressurized helium flow. Nuclear reaction takes place if the bed is in fluidized conditions at a void fraction above 80% and it

T. H. J. J. Van Der Hagen; H. Van Dam

1996-01-01

273

Electrically Indirectly Heated Fluidized Beds  

Microsoft Academic Search

An important class of fluidized beds has been investigated, those that are indirectly heated by electrical elements inserted in the fluid flow before the bed. They are commonly used for drying, chemical synthesis, mixing, coating, and similar industrial processes. New models have been developed that are simple to manipulate and are determined by tests at only three flow rates. These

William K. Roots; Ersin Tulunay

1970-01-01

274

Atmospheric fluidized bed combustion advanced system concepts applicable to small industrial and commercial markets. Topical report, Level 2 extension.  

National Technical Information Service (NTIS)

Under a contract with the USDOE's Morgantown Energy Technology Center (METC), Riley Stoker Corporation (Riley) has developed an advanced industrial CFB combustion design utilizing eastern bituminous coals as fuel. A pilot plant based on this design has be...

T. R. Ake V. B. Dixit R. K. Mongeon

1993-01-01

275

APPLICATION OF FLUIDIZED-BED TECHNOLOGY TO INDUSTRIAL BOILERS  

EPA Science Inventory

The report gives results of a paper study of the application potential of coalfired fluidized-bed boilers (FBB's) in the industrial use sector. It considers: the ability of coal-fired FBB's to meet the requirements of industrial users, including cost, reliability, maintainability...

276

DMEC-1 Pressurized Circulating Fluidized-Bed Demonstration Project  

SciTech Connect

The DMEC-1 project will demonstrate the use of Pyropower`s PYROFLOW pressurized circulating fluidized bed technology to repower an existing coal fired generating station. This will be the first commercial application of this technology in the world. The project is now in budget period 1, the preliminary design phase.

Kruempel, G.E.; Ambrose, S.J. [Midwest Power, Des Moines, IA (United States); Provol, S.J. [Pyropower Corp., San Diego, CA (United States)

1992-12-01

277

Factors limiting limestone utilization efficiency in fluidized-bed combustors  

Microsoft Academic Search

The factors which determine the quantity of limestone needed to obtain acceptable SOâ emission levels in the flue gas from fluidized-bed combustors have been reviewed. The most important factors are the mole ratio of calcium (in the stone) to sulfur (in the coal) in the feed, the gas phase residence time, the temperature, and the type of limestone. Both calcitic

I. Johnson; J. Shearer; R. Snyder; G. J. Vogel

1978-01-01

278

Engineer, Design, Construct, Test and Evaluate a Pressurized Fluidized Bed Pilot Plant Using High Sulfur Coal for Production of Electric Power.  

National Technical Information Service (NTIS)

The fluidized bed heat transfer characteristics of vertical finned and unfinned tube heat exchangers were examined in a 12-inch FluoSolids Reactor. Four different heat exchanger tubes were used. The studies were conducted on an isolated U-tube immersed in...

1977-01-01

279

Use of modified enzymes for the solubilization\\/liquefaction of bituminous coal in a fluidized-bed reactor  

Microsoft Academic Search

Biocatalysts allow the solubilization\\/liquefaction of coal at nearambient temperatures. This research has focused on the chemical\\u000a modification of enzymes to enhance their solubility and activity in organic media, and on optimal reactor design for a biocatalyst\\u000a coal liquefaction process. Modification of hydrogenase and cytochrome c using dinitrofluorobenzene (DNFB) or methoxypolyethylene\\u000a glycolp-nitrophenyl carbonate (PEG-n) has effected increased solubilities up to 20

Eric N. Kaufman; Charles D. Scott; Charlene A. Woodward; Timothy C. Scott

1995-01-01

280

Materials problems in fluidized-bed combustion systems: review of the information on gas turbine materials in coal combustion environments  

Microsoft Academic Search

This report condenses into a single document the available information related to the performance of gas turbine materials operated in the effluent from the combustion of coal. The information summarized originated from three sources: work performed in the period 1940-1970 to establish the potential for a direct coal-fired gas turbine, actual operating experience of gas turbines in particulate-laden environments, and

R. L. McCarron; D. A. Grey

1980-01-01

281

Status of Westinghouse coal-fueled combustion turbine programs  

Microsoft Academic Search

Developing clean, efficient, cost effective coal utilization technologies for future power generation is an essential part of our National Energy Strategy. Westinghouse is actively developing power plants utilizing advanced gasification, atmospheric fluidized beds (AFB), pressurized fluidized beds (PFB), and direct firing technology through programs sponsored by the U.S. Dept. of Energy (DOE). The DOE Office of Fossil Energy is sponsoring

A. J. Scalzo; D. J. Amos; R. L. Bannister; R. V. Garland

1992-01-01

282

Pressurized fluidized bed combined cycle for electric power generation  

Microsoft Academic Search

The Pressurized Fluidized Bed Combined Cycle (PFB\\/CC) is an efficient, cost-effective and environmentally attractive utility power plant concept which will permit the near-term substitution of domestic coal for imported oil. The combustor\\/steam generator is based on an advanced coal combustion process which results in greater than 99% carbon utilization, adsorption of 95% or more of the coal's sulfur in the

D. Lessard; D. J. Najewicz; R. Roberts

1982-01-01

283

Parametric performance studies on fluidized-bed heat exchangers  

NASA Astrophysics Data System (ADS)

The performance of single and multistage shallow fluidized beds is investigated for possible application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. Tests are conducted to (1) investigate the effects of fouling due to liquid condensate in the gas stream on fluidized bed heat exchanger performance, (2) investigate the performance of fluidized beds which are staged using baffle plates, and (3) investigate the effects of different heat exchanger surface geometries. Work is progressing in selecting the conditions for that portion of the program involving fouling by a liquid condensate, and in modifying the fluidized bed heat exchanger facility for the fouling experiments. Preliminary tests were conducted with water vapor injection. Water vapor and glycerol vapor were chosen as the condensates. The results are summarized as follows: (1) heat exchanger performance is seriously degraded by condensation when the dew point temperature exceeds the heat exchanger wall temperature; and (2) the performance decrease occurs as a result of particle adherence to the heat exchanger surface and not as a result of particle agglomeration.

Stoeffler, R. C.

1982-01-01

284

Program plan for development of hot dirty-gas heat exchangers for coal-gasification systems. [Entrained-flow, moving bed, and fluidized-bed gasifiers  

Microsoft Academic Search

This report deals with the heat exchanger applications, and its scope includes a broad range of gasification systems, such as the generic models for entrained-flow, moving-bed, and fluidized-bed gasifiers. The major application of hot dirty-gas heat exchangers is in the area of heat recovery for improved gasifier efficiency. The inlet temperature requirements for these heat exchangers varies from approx. 650

Churnetski

1983-01-01

285

Development of a Simulation Model for Fluidized Bed Mild Gasifier  

Microsoft Academic Search

A mild gasification method has been developed to provide an innovative clean coal technology. The objective of this study is to developed a numerical model to investigate the thermal-flow and gasification process inside a specially designed fluidized-bed mild gasifier using the commercial CFD solver ANSYS\\/FLUENT. Eulerain-Eulerian method is employed to calculate both the primary phase (air) and secondary phase (coal

AKM Monayem Hossain Mazumder

2010-01-01

286

Fluidized bed incineration of solid wastes and sludges : Viable technology for energy and environment.  

National Technical Information Service (NTIS)

The results of experimental combustion tests carried out in a fluidized bed pilot plant burning different types of refuse (municipal solid wastes, refuse derived fuels, agro-industrial wastes) are presented. The reactor is an atmospheric-bubbling-fluidize...

N. Brunetti F. Ciampa C. De Cecco S. Zuccotti

1992-01-01

287

Regeneration of Calcium-Based SO2 Sorbents for Fluidized-Bed Combustion: Engineering Evaluation.  

National Technical Information Service (NTIS)

The report gives results of an engineering evaluation of regeneration of calcium-based SO2 sorbents (limestone and dolomite) for application in both atmospheric and pressurized fluidized-bed combustion (FBC) processes. Economics of FBC power plants, opera...

R. A. Newby S. Katta D. L. Keairns

1978-01-01

288

Materials for Coal Conversion and Use. Volume II, Part I and II. Final Report on Task 005.  

National Technical Information Service (NTIS)

ESCOE is reviewing the work done to date on behavior of materials in coal conversion and utilitization working environments. The complete report consists of three volumes. Volume I, Materials of Construction for Atmospheric Fluidized Bed Coal Combustion, ...

V. K. Nangia

1979-01-01

289

Fluidized bed deposition of diamond  

DOEpatents

A process for coating a substrate with diamond or diamond-like material including maintaining a substrate within a bed of particles capable of being fluidized, the particles having substantially uniform dimensions and the substrate characterized as having different dimensions than the bed particles, fluidizing the bed of particles, and depositing a coating of diamond or diamond-like material upon the substrate by chemical vapor deposition of a carbon-containing precursor gas mixture, the precursor gas mixture introduced into the fluidized bed under conditions resulting in excitation mechanisms sufficient to form the diamond coating.

Laia, Jr., Joseph R. (Los Alamos, NM); Carroll, David W. (Los Alamos, NM); Trkula, Mitchell (Los Alamos, NM); Anderson, Wallace E. (Los Alamos, NM); Valone, Steven M. (Santa Fe, NM)

1998-01-01

290

Staged cascade fluidized bed combustor  

DOEpatents

A fluid bed combustor comprising a plurality of fluidized bed stages interconnected by downcomers providing controlled solids transfer from stage to stage. Each stage is formed from a number of heat transfer tubes carried by a multiapertured web which passes fluidizing air to upper stages. The combustor cross section is tapered inwardly from the middle towards the top and bottom ends. Sorbent materials, as well as non-volatile solid fuels, are added to the top stages of the combustor, and volatile solid fuels are added at an intermediate stage.

Cannon, Joseph N. (4103 Farragut St., Hyattsville, MD 20781); De Lucia, David E. (58 Beacon St., Apt. No. 2, Boston, MA 02108); Jackson, William M. (5300 McArthur Blvd., NW., Washington, DC 20016); Porter, James H. (P.O. Box 1131, Daggett Ave., Vineyard Haven, MA 02568)

1984-01-01

291

Rivesville multicell fluidized-bed boiler. Quarterly technical progress report, October-December 1979  

SciTech Connect

The objective of this program is to design, construct and test a multicell fluidized-bed boiler as a pollution-free method of burning high-sulfur or highly corrosive coals without excessive maintenance problems. The fluidized-bed boiler will provide approximately 300,000 pounds of steam per hour. Steam pressure and temperature conditions were selected to meet requirements of the site at which the boiler was installed.

Not Available

1980-01-01

292

Constitutive laws in liquid-fluidized beds  

Microsoft Academic Search

The objective of the present work is to test experimentally the two-phase modelling approach which is widely used in fluidization. A difficulty of this way of modelling fluidized beds is the use of empirical relations in order to close the system of equations describing the fluidized bed as a two-phase continuum, especially concerning the description of the solid phase. We

Paul Duru; Maxime Nicolas; John Hinch; Élisabeth Guazzelli

2002-01-01

293

Modeling of wet jet in fluidized bed  

Microsoft Academic Search

A wet jet zone is established in many applications wherever feeding and dispersing a liquid, solution or slurry into fluidized bed by gases is needed. In the present study, a simple mathematical model has been developed to simulate the wet jet in fluidized bed. The different stages involved inside the jet zone have been estimated and analyzed.The evaporation stage of

F. Okasha; M. Miccio

2006-01-01

294

Review of fluidized bed combustion technology in the United States  

SciTech Connect

Work on fluidized bed combustion (FBC) began in the United States in the mid-1960's, with primary emphasis on industrial applications. With passage of the Clean Air Act in 1970, the environmental benefits of the technology soon attracted interest. This provided the impetus for expanded effort focused on the reduced NO/sub x/ emissions resulting from lower combustion temperature and SO/sub 2/ capture by means of chemical reaction with limestone or dolomite in the fluidized bed. The oil embargo in 1973 further stimulated interest in FBC technology. Recently interest in fuel flexibility has sustained the interest in FBC in the US. Several US manufacturers presently offer atmospheric fluidized bed combustion (AFBC) and circulating fluidized bed combustion (CFBC) units for industrial applications. However, FBC for electric power generation remains in the development and demonstration phase. The Tennessee Valley Authority (TVA) and Electric Power Research Institute (EPRI) are operating a 20-MW(e) AFBC utility pilot plant and are proceeding with plans for a 160-MW(e) demonstration plant with other participants. Research on pressurized fluidized bed combustion (PFBC) has been under way at Grimethorpe in South Yorkshire, England, at the Curtiss-Wright Pilot Plant in the US, and at other smaller test facilities. An emerging turbocharged PFBC concept will likely stimulate more near-term interest in PFBC technology for both industrial and utility applications. The major US programs and test facilities are described herein. The remaining technical uncertainties and the future outlook for the technology are also discussed. 39 refs.

Fox, E.C.; Krishnan, R.P.; Daw, C.S.; Jones, J.E. Jr.

1985-01-01

295

Holdup correlations in slurry-solid fluidized beds  

SciTech Connect

The use of slurry-solids fluid beds plays an important role in the development of synthetic fuels and the hydrogen processing of petroleum resids. In the H-Coal process in particular, coal oil slurries are processed over extrudates of hydrodesulfurization catalyst. The objective of this note is to present a model which describes the volume fraction occupied by the slurry phase. The accurate prediction of the liquid holdup is important not only for the calculation of the bed height in liquid solid fluidized beds, but also is required for the development of a model predicting the holdup in three-phase fluidized beds. In the present publication, the application of two different correlations is considered: (1) the Richardson and Zaki; and (2) Ramamurthy and Sabbaraju.

Vasalos, I.A.; Rundell, D.N.; Megiris, K.E.; Tjatjopoulos, G.J.

1980-01-01

296

Estimation of nonfuel operation and maintenance costs for advanced circulating fluidized-bed and advanced natural gas-fired combined cycle power plants  

Microsoft Academic Search

Operation and maintenance cost estimating methodologies for advanced coal-fired atmospheric circulating fluidized-bed and advanced natural gas-fired combined cycle electric power plants are presented. The purpose of these cost estimating relationships is for use in long range planning and evaluation of the economics of use of these technologies for electric power generation. Projected annual costs of reference plants at ten different

J. J. Coen; H. I. Bowers; M. L. Myers

1989-01-01

297

Four Rivers second generation Pressurized Circulating Fluidized Bed Combustion Project  

SciTech Connect

Air Products has been selected in the DOE Clean Coal Technology Round V program to build, own, and operate the first commercial power plant using second generation Pressurized Circulating Fluidized Bed (PCFB) combustion technology. The four Rivers Energy Project (Four Rivers) will produce up to 400,000 lb/hr steam, or an equivalent gross capacity of 95 MWe. The unit will be used to repower an Air Products chemicals manufacturing facility in Calvert City, Kentucky.

Holley, E.P.; Lewnard, J.J. [Air Products and Chemicals, Inc. (United States); von Wedel, G. [LLB Lurgi Lentjes Babcock Energietechnik (GmbH); Richardson, K.W. [Foster Wheeler Energy Corp. (United States); Morehead, H.T. [Westinghouse Electric Corp. (United States)

1995-04-01

298

Process for generating electricity in a pressurized fluidized-bed combustor system  

Microsoft Academic Search

This patent describes a method of generating electric power from coal using a pressurized fluidized-bed combustor system. It comprises: supplying coal in a feed slurry comprising water, coal and a sulfur sorbent to a combustor; combusting the coal with air in a pressurized combustor chamber in the combustor to produce a flue gas; controlling the combustor temperature by varying an

Kasper

1991-01-01

299

An overview of fluidized-bed combustion /FBC/ design practice  

NASA Astrophysics Data System (ADS)

A short history of fluidized bed coal combustion is provided, noting that addition of a limestone bed contributes to sulfur retention, and comparisons are made with stoker and pulverized bed boilers. Advantages to fluidized bed combustion (FBC) are given as the thermal inertia of the limestone bed, inherent vigorous mixing for turbulent, efficient combustion, and larger particle size than in a catalytic cracker. Major components of an FBC are described, including windbox, distributor, feeder system, combustion chamber, bed material drainage, and primary dust recovery system. Fundamental differences between FBC and conventional boiler technology are stressed and design considerations for an FBC are listed with explanations. Recirculation of fly ash is shown to be effective only with an in-combustor vortex, which returns the ash to the flame before it has time to cool. Finally, ongoing experiments to determine the relative usefulness of burning various alternate fuels such as shales, lignite, and shredded tires in an FBC are reported.

Shang, J.-Y.; Notestein, J. E.; Mei, J. S.

300

Optimization of heating with heat treatment in fluidized bed  

Microsoft Academic Search

1.Intensive movement of particles resulting from pseudoliquification increases the rate of heat transfer, making it possible to shorten heating times and also ensure even distribution of temperatures in the heating chamber. The heat-transfer coefficient is somewhat lower in a fluidized bed than in a salt bath but 2.5–4 times higher than in furnaces with a controlled atmosphere.2.The particles constituting the

L. Drugé; V. Pantya

1979-01-01

301

Fluidized-bed retrofit a practical alternative to FGD  

Microsoft Academic Search

When SOâ emissions from an existing utility boiler must be reduced, retrofitting for fluidized-bed combustion may be an attractive alternative. In addition to reducing atmospheric pollutants during combustion, FBC retrofits allow simultaneous burning of a wide range of low-cost fuels. Also, since new components are incorporated in the steam generator rather than added on as pollution-control equipment, they extend the

T. E. Stringfellow; F. S. Nolte; W. L. Sage

1984-01-01

302

Enhanced durability of desulfurization sorbents for fluidized-bed applications  

SciTech Connect

Advanced integrated gasification combined cycle (IGCC) power systems require the development of high-temperature desulfurization sorbents capable of removing hydrogen sulfide from coal gasifier down to very low levels. The objective of this investigation was to identify and demonstrate methods for enhancing the long-term chemical reactivity and mechanical strength of zinc ferrite, a leading regenerable sorbent, for fluidized-bed applications. Fluidized sorbent beds offer significant potential in IGCC systems because of their ability to control the highly exothermic regeneration involved. However, fluidized beds require a durable, attrition-resistant sorbent in the 100--300 {mu}m size range. A bench-scale high-temperature, high- pressure (HTHP) fluidized-bed reactor (7.6-cm I.D.) system capable of operating up to 24 atm and 800{degree}C was designed, built and tested. A total of 175 sulfidation-regeneration cycles were carried out using KRW-type coal gas with various zinc ferrite formulations. A number of sorbent manufacturing techniques including spray drying, impregnation, crushing and screening, and granulation were investigated. While fluidizable sorbents prepared by crushing durable pellets and screening had acceptable sulfur capacity, they underwent excessive attrition during multicycle testing. The sorbent formulations prepared by a proprietary technique were found to have excellent attrition resistance and acceptable chemical reactivity during multicycle testing. However, zinc ferrite was found to be limited to 550{degree}C, beyond which excessive sorbent weakening due to chemical transformations, e.g., iron oxide reduction, was observed.

Gupta, R.P.; Gangwal, S.K.

1991-06-01

303

Use of fluidized bed combustion by-products for liners and alkali substitutes. Technical report, December 1, 1994February 28, 1995  

Microsoft Academic Search

Fluidized Bed Combustion (FBC) of coal eliminates most emissions of sulfur and nitrogen oxides, but produces sizable volumes of a solid residue that EPA may require to be placed in capped and lined landfills. Fluidized Bed Combustors are one of the most promising growth markets for Illinois coal and imposing cap and liner requirements would render the technology economically inviable.

B. C. Paul; S. Esling; F. Pisani; T. Wells

1996-01-01

304

Technology Overview: Circulating Fluidized-Bed Combustion.  

National Technical Information Service (NTIS)

The report summarizes the current technical status of circulating fluidized-bed combustion (CFBC). Companies that are involved in investigating this technology and/or developing commercial systems are discussed, along with system descriptions and availabl...

D. R. Roeck

1982-01-01

305

TECHNOLOGY OVERVIEW: CIRCULATING FLUIDIZED-BED COMBUSTION  

EPA Science Inventory

The report summarizes the current technical status of circulating fluidized-bed combustion (CFBC). Companies that are involved in investigating this technology and/or developing commercial systems are discussed, along with system descriptions and available cost information. CFBC ...

306

Approximate Theory of Fluidized Bed Coating.  

National Technical Information Service (NTIS)

The fluidized-bed system for coating metals with plastics has developed from a laboratory curiosity barely thirteen years ago to a routine process in operation today in more than 360 major companies. Applications are increasing in the appliance, chemical ...

W. H. Chen C. Gutfinger

1968-01-01

307

Single-Stage Fluidized-Bed Gasification.  

National Technical Information Service (NTIS)

The single-stage fluidized-bed gasification process, in addition to being a simple system, maximizes gas production and allows the economic exploitation of small peat deposits. The objective of this gasification project is to conduct experiments in order ...

F. S. Lau D. M. Rue S. A. Weil D. V. Punwani

1982-01-01

308

Gasification in Fluidized Beds — Present Status & Design  

NASA Astrophysics Data System (ADS)

Biomass has made great in-roads in its use in energy and chemical industries. Gasification is one of the major means for its conversion. For thermo-chemical conversion of biomass three major gas-solid contacting processes, fixed bed, entrained bed and fluidized bed are used. Various versions of fixed bed gasifier (up-draft, down-draft, and side-draft) proved successful but primarily in small capacity units while entrained bed reactors found favour in very large capacity units. Fluidized bed gasifier fills the important intermediate size range. A review of the current commercial use of fluidized bed gasifier shows that it is yet to take the centre stage in the gasification market. This paper examines the issues preventing wider scale use of fluidized bed gasifier and what is the current state of research in those issues.

Basu, Prabir; Acharya, Bishnu; Dutra, Animesh

309

Simulation of a Circulating Fluidized Bed Combustor with Shrinking Core and Emission Models  

Microsoft Academic Search

A Circulating Fluidized Bed Combustor (CFBC) is a highly efficient combustor. It can handle various types of solid fuels such as coal, biomass or agricultural wastes. Coal and biomass have been used as fuel to generate heat for a boiler in many industries. To predict the proper amount of mixed fuel and to reduce the emission from coal burning, a

Natthapong Ngampradit; Pornpote Piumsomboon; Boonrod Sajjakulnukit

310

Hot corrosion/erosion testing of materials for applications for advanced power conversion systems using coal-derived fuels. Fireside II. Evaluation of turbine materials for use in a coal-fired fluidized bed combustion environment. Task II. Final report  

SciTech Connect

This report summarizes the results of the General Electric Fireside Corrosion Task II Program. This program was designed to evaluate the erosion/corrosion behavior of gas turbine nozzle guide vane and rotor blade materials in both simulated and actual pressurized fluidized bed combustor (PFBC) environments. Simulation testing included exposing disc-shaped specimens in atmospheric pressure small burner rig test stands operated at 1600/sup 0/F (871/sup 0/C) for periods up to 1300 hours. PFBC evaluation testing consisted of exposing airfoil shaped specimens to the efflux from a PFBC in a turbine test section installed in the Exxon PFBC Miniplant facility at Linden, N.J. Candidate gas turbine materials included three cast vane and blade base alloys, FSX-414, IN-738, and U-700, and one protective coating system, platinum-chromium-aluminide (RT-22). Small burner rig testing consistently showed the nickel-base alloys U-700 and IN-738 most susceptible to corrosion/sulfidation, followed by the cobalt-base alloy FSX-414; the RT-22 coating on IN-738 was most resistant to hot corrosion attack. Parts life estimates have been made for the nickel and cobalt-base alloys based on corrosion rates determined from the PFBC testing.

Not Available

1980-09-01

311

Bed material agglomeration during fluidized bed combustion. Technical progress report, January 1, 1995--March 31, 1995  

SciTech Connect

Experiments performed support the hypothesis that a reducing atmosphere during fluidized bed coal combustion contributes to the formation of agglomerates. Reducing conditions are imposed by controlling the amount of combustion air supplied to the combustor, 50% of theoretical in these experiments. These localized reducing conditions may arise from either poor lateral bed mixing or oxygen-starved conditions due to the coal feed locations. Deviations from steady-state operating conditions in bed pressure drop may be used to detect agglomerate formation. Interpretation of the bed pressure drop was made more straightforward by employing a moving average difference method. During steady-state operation, the difference between the moving point averages should be close to zero, within {plus_minus}0.03 inches of water. Instability within the combustor, experienced once agglomerates begin to form, can be recognized as larger deviations from zero, on the magnitude of {plus_minus}0.15 inches of water.

Brown, R.C.; Dawson, M.R.; Smeenk, J.L.

1995-04-01

312

Refractory experience in circulating fluidized bed combustors, Task 7. Final report  

SciTech Connect

This report describes the results of an investigation into the status of the design and selection of refractory materials for coal-fueled circulating fluidized-bed combustors. The survey concentrated on operating units in the United States manufactured by six different boiler vendors: Babcock and Wilcox, Combustion Engineering, Foster Wheeler, Keeler Dorr-Oliver, Pyropower, and Riley Stoker. Information was obtained from the boiler vendors, refractory suppliers and installers, and the owners/operators of over forty units. This work is in support of DOE`s Clean Coal Technology program, which includes circulating fluidized-bed technology as one of the selected concepts being evaluated.

Vincent, R.Q.

1989-11-01

313

Use of circulating-fluidized-bed combustors in compressed-air energy storage systems  

Microsoft Academic Search

This report presents the result of a study conducted by Energy Storage and Power Consultants (ESPC), with the objective to develop and analyze compressed air energy storage (CAES) power plant concepts which utilize coal-fired circulating fluidized bed combustors (CFBC) for heating air during generating periods. The use of a coal-fired CFBC unit for indirect heating of the compressed air, in

M. Nakhamkin; M. Patel

1990-01-01

314

Experimental development of a multi-solid fluidized bed reactor concept  

Microsoft Academic Search

Battelle's Columbus Division is developing a coal mild gasification process based upon the Multi-Solid Fluidized bed reactor system to produce high quality liquid and gaseous products. This process uses 2-stages to gasify coal at high throughputs to produce a range of products in compact reactors without requiring an oxygen plant. 8 refs., 14 figs., 12 tabs.

R. D. Litt; M. A. Paisley; T. L. Tewksbury

1990-01-01

315

Experimental development of a multi-solid fluidized bed reactor concept  

Microsoft Academic Search

The Multi-Solid Fluidized bed reactor system uses 2-stages to gasify coal at high throughputs to produce a range of products in compact reactors without requiring an oxygen plant. Data generated on the process has shown that approximately 20% by weight of the incoming coal can be converted to liquid products and an additional 20% to a fuel gas with a

R. D. Litt; M. A. Paisley; T. L. Tewksbury

1990-01-01

316

Process for generating electricity in a pressurized fluidized-bed combustor system  

Microsoft Academic Search

A process and apparatus for generating electricity using a gas turbine as part of a pressurized fluidized-bed combustor system wherein coal is fed as a fuel in a slurry in which other constituents, including a sulfur sorbent such as limestone, are added. The coal is combusted with air in a pressurized combustion chamber wherein most of the residual sulfur in

Kasper

1991-01-01

317

Process and apparatus for generating electricity in a pressurized fluidized-bed combustor system  

Microsoft Academic Search

A process and apparatus for generating electricity using a gas turbine as part of a pressurized fluidized-bed combustor system wherein coal is fed as a fuel in a slurry in which other constituents, including a sulfur sorbent such as limestone, are added. The coal is combusted with air in a pressurized combustion chamber wherein most of the residual sulfur in

Kasper

1990-01-01

318

Parametric performance studies on fluidized-bed heat exchangers. Task 1: Fouling characteristics  

NASA Astrophysics Data System (ADS)

Analyses and experiments are being performed to investigate the heat transfer performance of single and multistage shallow fluidized beds for application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. Tests were conducted to investigate the effects of liquid condensate fouling on fluidized bed heat exchanger performance. Liquid condensates used in these tests were water and glycerol (which is more viscous than water). The tests showed that fluidized bed heat exchanger performance is degraded by condensation within the bed and the degradation is caused by bed particles adhering to the heat exchanger surface, not by particle agglomeration. Liquid condensate did not continuously build up within the bed. After a period of dry out, heat transfer equal to that obtained prior to condensation was again obtained.

Stoeffler, R. C.

1982-09-01

319

Modelling of Sulphur Dioxide Capture in Fluidized Bed Combustion.  

National Technical Information Service (NTIS)

The paper discusses the relation between SO2 models and comprehensive fluidized bed models. By comprehensive models is here meant complex models treating the hydrodynamics and combustion reactions in a fluidized bed. SO2 models can be both independent mod...

A. Lyngfelt

1989-01-01

320

Pressurized circulating fluidized-bed combustion for power generation  

SciTech Connect

Second-generation Pressurized Circulating Fluidized Bed Combustion (PCFBC) is the culmination of years of effort in the development of a new generation of power plants which can operate on lower-quality fuels with substantially improved efficiencies, meet environmental requirements, and provide a lower cost of electricity. Air Products was selected in the DOE Clean Coal Technology Round V program to build, own, and operate the first commercial power plant using second-generation PCFBC technology, to be located at an Air Products chemicals manufacturing facility in Calvert City, Kentucky. This paper describes the second-generation PCFBC concept and its critical technology components.

Weimer, R.F.

1995-08-01

321

Fluidized bed combustion of alternate fuels. Final report  

SciTech Connect

Fluidized bed combustion (FBC) technology offers the opportunity combust a broader range of fuels than previously possible with other technologies. FBC boilers are currently being used throughout the world to dispose of a wide range of solid and semi-solid waste fuels, including municipal and industrial solid wastes and sludges, agricultural wastes, and coal mining or cleaning wastes. FBCs can also accommodate cofiring waste fuels in units designed for coal or other solid fuels with relative ease compared to conventional technology. The capacity and experience base for coal-fired FBCs has increased in recent years so that utility-scale reheat units of 200-300 MWe in size are now commercially available, and larger units are now being considered. As utilities install fluidized bed boilers to generate power, it is anticipated that many will at some point consider cofiring one or more waste fuels either together or with coal to reduce the quantity and cost of the primary fuel, and in many cases, help offset the environmental impact of other disposal options such as landfills. In order to assist the industry in their evaluations, this report summarizes the fuel characteristics, experience base, and technical issues associated with burning selected fuels using FBC technology, including: Municipal Solid Wastes; Biomass; Sewage Sludge; Paper Manufacturing and Recycling Wastes; Scrap Tires; and Automobile Wastes.

Howe, W.C.; Divilio, R.J. [Combustion Systems, Inc., Aptos, CA (United States)

1993-12-01

322

Fluidized bed reactor system and method having a heat exchanger  

Microsoft Academic Search

A fluidized bed reactor system is described comprising a reactor, means for supporting a fluidized bed of combustible particulate material in said reactor, heat exchange means disposed adjacent said reactor, separating means for receiving a mixture of flue gases and entrained particulate material from said fluidized bed and separating said particulate material from said flue gases, means for passing said

Garcia-Mallol

1993-01-01

323

Fluidized bed reactor having an integrated recycle heat exchanger  

Microsoft Academic Search

This patent describes a fluidized bed combustion system. It includes a furnace, a fluidized bed of combustible particulate material disposed in the furnace, a recycle heat exchanger disposed adjacent the furnace and sharing a common wall with the furnace separating means for receiving a mixture of flue gases and entrained particulate material from a fluidized bed in the furnace and

W. R. Campbell; M. G. Alliston; B. H. Sisson

1990-01-01

324

High-temperature erosion–oxidation of uncoated and FB-CVD aluminized and aluminized–siliconized 9Cr–1Mo steel under fluidized-bed conditions  

Microsoft Academic Search

Fluidized-bed combustion is one of the methods to generate energy in a clean and efficient way from a variety of fuels. However, conditions in fluidized-bed boilers: high temperature, oxidizing atmosphere and impacts by fluidized sand particles, can cause significant degradation of some boiler components, such as heat exchangers, by a combination of oxidation attack and erosion wear. Protective coatings, deposited

E. Huttunen-Saarivirta; S. Kalidakis; F. H. Stott; F. J. Perez; T. Lepistö

2009-01-01

325

ESTABLISHMENT OF AN ENVIRONMENTAL CONTROL TECHNOLOGY LABORATORY WITH A CIRCULATING FLUIDIZED-BED COMBUSTION SYSTEM  

SciTech Connect

This report is to present the progress made on the project ''Establishment of an Environmental Control Technology Laboratory (ECTL) with a Circulating Fluidized-Bed Combustion (CFBC) System'' during the period October 1, 2004 through December 31, 2004. The following tasks have been completed. First, the renovation of the new Combustion Laboratory and the construction of the Circulating Fluidized-Bed (CFB) Combustor Building have proceeded well. Second, the detailed design of supporting and hanging structures for the CFBC was completed. Third, the laboratory-scale simulated fluidized-bed facility was modified after completing a series of pretests. The two problems identified during the pretest were solved. Fourth, the carbonization of chicken waste and coal was investigated in a tube furnace and a Thermogravimetric Analyzer (TGA). The experimental results from this study are presented in this report. Finally, the proposed work for the next quarter has been outlined in this report.

Wei-Ping Pan; Andy Wu; John T. Riley

2005-01-30

326

FBC: Gaining acceptance. [Fluidized Bed Combustion  

SciTech Connect

This article addresses the growing acceptance of fluidized bed combustion as a technology appropriate for use in dual-purpose power plants. The article reviews projects for cogeneration in California, a demonstration plant sponsored by the US Department of Energy in Ohio (this plant also incorporates combined cycle operation), and an electric power/greenhouse project in Pennsylvania.

Gawlicki, S.M.

1991-04-01

327

Stability in a Denitrifying Fluidized Bed Reactor  

Microsoft Academic Search

This study evaluates changes in the microbial community structure and function of a pilot-scale denitrifying fluidized bed reactor during periods of constant operating conditions and periods of perturbation. The perturbations consisted of a shutdown period without feed, two disturbances in which biofilms were mechanically sheared from carrier particles, and a twofold step increase in feed nitrate concentration. In the absence

M. Gentile; T. Yan; S. M. Tiquia; M. W. Fields; J. Nyman; J. Zhou; C. S. Criddle

2006-01-01

328

Fluidized bed combustion - prospects and role.  

National Technical Information Service (NTIS)

Fluidized bed combustion (FBC) is a widespread commercial combustion technique with more than 700 units in operation and with a total thermal capacity of almost 30 000 MW. About 90 % of this capacity is in the following eight countries: U.S., FRG, France,...

M. Hupa S. Bostroem

1991-01-01

329

Heat exchange tube for fluidized bed reactor  

Microsoft Academic Search

Liquid containing heat transfer tube for use in a fluidized bed reactor is disclosed which is protected against erosive effects of the fluidized medium by having radially outwardly extending fins on its outer surface and by having the entire outer surface area between the fins covered by a layer of an abrasion resistant refractory which is supported by a metallic

Thompson

1978-01-01

330

Agglomeration in fluidized beds: detection and counteraction  

Microsoft Academic Search

Fluidized beds comprise a quantity of solid particles that is suspended by an upward flowing gas. They are used for a variety of processes in the chemical industry, such as catalytic reactions, drying, coating and energy conversion. A major problem in industrial practice is the occurrence of unwanted agglomeration, i.e. solid particles adhering to each other and forming larger agglomerates.

Bartels. M

2008-01-01

331

Sequential modeling of fluidized bed paddy dryer  

Microsoft Academic Search

A sequential method was developed to model a continuous plug flow fluidized bed dryer. The method is based on dividing the dryer into sections in series with ideal mixing for both solid and gas phases in each section. In order to determine the proper number of sections, drying experiments were carried out using paddy at different operating conditions. It was

Navid Bizmark; Navid Mostoufi; Rahmat Sotudeh-Gharebagh; Hossein Ehsani

2010-01-01

332

Fluidized bed combustion of alternative solid fuels  

Microsoft Academic Search

The fluidized bed combustion of a number of alternative fuels of practical interest has been analyzed by a combination of experimental and modeling techniques. Solid fuels of widely different origin (biomass, agricultural, civil and industrial wastes) have been considered in this work. A lab-scale experimental campaign was carried out to evaluate the comminution (fragmentation, attrition) behavior of the fuels. Experimental

Fabrizio Scala; Riccardo Chirone

2004-01-01

333

Particle pressures in fluidized beds. Final report  

SciTech Connect

This project studies the particle pressure, which may be thought of as the force exerted by the particulate phase of a multiphase mixture, independently of that exerted by other phases. The project is divided into two parts, one concerning gas and the other liquid fluidized beds. Previous work on gas fluidized beds had suggested that the particle pressures are generated by bubbling action. Thus, for these gas fluidized bed studies, the particle pressure is measured around single bubbles generated in 2-D fluidized beds, using special probes developed especially for this purpose. Liquid beds are immune from bubbling and the particle pressures proved too small to measure directly. However, the major interest in particle pressures in liquid beds lies in their stabilizing effect that arises from the effective elasticity (the derivative of the particle pressure with respect to the void fraction), they impart to the bed. So rather than directly measure the particle pressure, the authors inferred the values of the elasticity from measurements of instability growth in liquid beds; the inference was made by first developing a generic stability model (one with all the normally modeled coefficients left undetermined) and then working backwards to determine the unknown coefficients, including the elasticity.

Campbell, C.S.; Rahman, K.; Jin, C.

1996-09-01

334

Particle Pressures in Fluidized Beds. Final report  

SciTech Connect

This project studies the particle pressure, which may be thought of as the force exerted by the particulate phase of a multiphase mixture, independently of that exerted by other phases. The project is divided into two parts, one concerning gas and the other liquid fluidized beds. Previous work on gas fluidized beds had suggested that the particle pressures are generated by bubbling action. Thus, for these gas fluidized bed studies, the particle pressure is measured around single bubbles generated in 2-D fluidized beds, using special probes developed especially for this purpose. Liquid beds are immune from bubbling and the particle pressures proved too small to measure directly. However, the major interest in particle pressures in liquid beds lies in their stabilizing effect that arises from the effective elasticity (the derivative of the particle pressure with respect to the void fraction): they impart to the bed. So rather than directly measure the particle pressure, we inferred the values of the elasticity from measurements of instability growth in liquid beds the inference was made by first developing a generic stability model (one with all the normally modeled coefficients left undetermined)and then working backwards to determine the unknown coefficients, including the elasticity.

Campbell, C.S.; Rahman, K.; Jin, C.

1996-09-01

335

SOLIDS TRANSPORT BETWEEN ADJACENT CAFB FLUIDIZED BEDS  

EPA Science Inventory

The report gives results of an experimental investigation of a pulsed, dense-phase pneumatic transport system for controlled circulation between adjacent fluidized beds. A model was developed to predict performance. The program provides technical support for EPA's program to demo...

336

Extinction studies in fluidized-bed combustors  

Microsoft Academic Search

The problem of thermal extinction in Fluidized Bed Combustors (FBC) and its relevance to turn down ratio (TDR) are addressed in this paper. Unlike the suspension mode burners, particles in FBC has a longer residence time compared to residence time of volatiles. Thus char combustion is expected to be better than combustion of volatiles. First analysis is carried out by

Annamalai

1983-01-01

337

Reversed flow fluidized-bed combustion apparatus  

DOEpatents

The present invention is directed to a fluidized-bed combustion apparatus provided with a U-shaped combustion zone. A cyclone is disposed in the combustion zone for recycling solid particulate material. The combustion zone configuration and the recycling feature provide relatively long residence times and low freeboard heights to maximize combustion of combustible material, reduce nitrogen oxides, and enhance sulfur oxide reduction.

Shang, Jer-Yu (Fairfax, VA); Mei, Joseph S. (Morgantown, WV); Wilson, John S. (Morgantown, WV)

1984-01-01

338

Fluidized bed reactor for fluoride removal  

Microsoft Academic Search

The common methods for fluoride removal from industrial wastewater involve chemical precipitation. This process generates large amounts of a water rich sludge requiring disposal with increasing costs. Due to the high water content and the low quality of the sludge, reuse of fluoride is not an economical option. The crystallization in a fluidized bed reactor offers an alternative to the

R. Aldaco; A. Irabien; P. Luis

2005-01-01

339

Electrically enhanced fluidized bed heat exchanger  

Microsoft Academic Search

The experiments have shown that a high level of electrical charging can be achieved in a fluidized bed of two resistive particle types; that bed stabilization rather than increased sensible heat transport dominates low frequency electric field effects on heat transfer with most bed loadings; and, hence, that applying an oscillatory potential difference between tubes or rods in a fluidized

D. L. Lessor; R. J. Robertus; G. L. Roberts

1994-01-01

340

Food Freezing in the Intermediate Fluidized Bed.  

National Technical Information Service (NTIS)

A new food freezing method has been investigated using the so-called intermediate fluidized bed in which the food was fluidized together with small particles for aid of the fluidization and heat transfer of the food. Formed alumina and refined salt partic...

M. Yumiyama

1988-01-01

341

Fluidized bed electrowinning of copper. Final report  

SciTech Connect

The objectives of the study were to: design and construct a 10,000- amp fluidized bed electrowinning cell for the recovery of copper from acidic sulfate solutions; demonstrate the technical feasibility of continuous particle recirculation from the electrowinning cell with the ultimate goal of continuous particle removal; and measure cell efficiency as a function of operating conditions.

NONE

1997-07-01

342

Fluidized bed adsorption of Cephalosporin C  

Microsoft Academic Search

Fluidized bed adsorption can substantially simplify the recovery of products from fermentation. There are, however, several critical parameters, which have a significant influence on the performance of such systems. This paper presents experimental results on the adsorption of an antibiotic, Cephalosporin C, on macroporous adsorbents of the polystyrene type and on an ion exchanger. Internals (static mixers) were used to

M Hicketier; K Buchholz

2002-01-01

343

Fluidization quality analyzer for fluidized beds  

DOEpatents

A control loop and fluidization quality analyzer for a fluidized bed utilizes time varying pressure drop measurements. A fast-response pressure transducer measures the overall bed pressure drop, or over some segment of the bed, and the pressure drop signal is processed to produce an output voltage which changes with the degree of fluidization turbulence. 9 figs.

Daw, C.S.; Hawk, J.A.

1995-07-25

344

Fluidization quality analyzer for fluidized beds  

DOEpatents

A control loop and fluidization quality analyzer for a fluidized bed utilizes time varying pressure drop measurements. A fast-response pressure transducer measures the overall bed pressure drop, or over some segment of the bed, and the pressure drop signal is processed to produce an output voltage which changes with the degree of fluidization turbulence.

Daw, C. Stuart (Knoxville, TN); Hawk, James A. (Oak Ridge, TN)

1995-01-01

345

Characterizing and modeling combustion of mild-gasification chars in pressurized fluidized beds  

SciTech Connect

Oak Ridge National Laboratory (ORNL) is supported by the Morgantown Energy Technology Center (METC) of the Department of Energy (DOE) under FWP-FEAA310 to characterize the fuel properties of liquid and char coproducts from the mild gasification of coal, Because most of the energy content of coals subjected to mild gasification is retained in the byproduct char, efficient and cost-effective utilization of the char is essential in insuring that candidate gasification processes are commercially viable. One potential use for char of particular interest to DOE is pressurized fluidized bed combustion (PFBC). PFBC is of particular interest because it has the potential for 10 to 30 percent greater overall energy efficiency than atmospheric fluidized bed combustion (AFBC), While bench-scale tools and analytical procedures for characterizing fuels for AFBC have been recently demonstrated, no such tools have been reliably demonstrated for PFBC. This report summarizes the results of joint research collaboration between ORNL and B&W that has been directed at modifying the previously developed AFBC fuel characterization procedures to be applicable for mild-gasification chars and PFBC conditions. The specific objectives were to: (1) characterize the combustion reactivity of a selected set of candidate mild- gasification chars at PFB conditions; (2) compare the measured char characteristics with those of more conventional PFBC fuels; (3) modify an AFBC computer code previously developed by B&W and ORNL for the Electric Power Research Institute (EPRI) to predict PFBC performance; and (4) apply the modified code and measured char combustion characteristics to make performance predictions for the candidate chars relative to more conventional fuels.

Daw, C.S.

1995-10-01

346

Performance analysis of co-firing waste materials in an advanced pressurized fluidized-bed combustor  

SciTech Connect

The co-firing of waste materials with coal in utility scale power plants has emerged as an effective approach to produce energy and manage municipal wastes. Leading this approach is the atmospheric fluidized-bed combustor (AFBC). It has demonstrated its commercial acceptance in the utility market as a reliable source of power by burning a variety of waste and alternative fuels. The application of pressurized fluidized-bed combustor (PFBC) technology, although relatively new, can provide significant enhancements to the efficient production of electricity while maintaining the waste management benefits of AFBC. A study was undertaken to investigate the technical and economical feasibility of co-firing a PFBC with coal and municipal and industrial wastes. Focus was placed on the production of electricity and the efficient disposal of wastes for application in central power station and distributed locations. Issues concerning waste material preparation and feed, PFBC operation, plant emissions, and regulations are addressed. The results and conclusions developed are generally applicable to current and advanced PFBC design concepts. Wastes considered for co-firing include municipal solid waste (MSW), sewage sludge, and industrial de-inking sludge. Conceptual designs of two power plants rated at 250 MWe and 150 MWe were developed. Heat and material balances were completed for each plant along with environmental issues. With the PFBC`s operation at high temperature and pressure, efforts were centered on defining feeding systems capable of operating at these conditions. Air emissions and solid wastes were characterized to assess the environmental performance comparing them to state and Federal regulations. This paper describes the results of this investigation, presents conclusions on the key issues, and provides recommendations for further evaluation.

Bonk, D.L.; McDaniel, H.M. [USDOE Morgantown Energy Technology Center, WV (United States); DeLallo, M.R. Jr.; Zaharchuk, R. [Gilbert/Commonwealth, Inc., Reading, PA (United States)

1995-07-01

347

Engineering systems analysis of pressurized fluidized-bed-combustion power systems  

Microsoft Academic Search

This effort was conducted to provde supporting data for the research and development program on pressurized fluidized bed combustor (PFBC) systems being continued under the auspices of the Office of Coal Utilization of DOE. This report deals with the first phase of the effort, designated Task 1, which was scoped to be a somewhat broad review of PFBC technology and

R. L. Graves; F. P. Griffin; M. E. Lackey

1982-01-01

348

Heat transfer to a bayonet heat exchanger immersed in a gas-fluidized bed  

Microsoft Academic Search

Bayonet tubes are frequently used for heat removal in fluidized bed coal combustors and gasifiers. They consist of two coaxial tubes, through which the cooling fluid flows; first through the inner tube, and then back through the annulus, or vice versa. Such a flow arrangement creates obvious difficulties in defining a characteristic temperature difference to which the heat transfer rate

A. Mathur; Z. H. Qureshi; S. C. Saxena

1983-01-01

349

DESIGN AND CONSTRUCTION OF A FLUIDIZED-BED COMBUSTION SAMPLING AND ANALYTICAL TEST RIG  

EPA Science Inventory

The report describes the design, construction, and installation of a fluidized-bed coal combustion sampling and analytical test rig in the High Bay Area (Wing G) of EPA's Industrial Environmental Research Laboratory (IERL), Research Triangle Park, North Carolina. The rig, to be u...

350

Nucla Circulating Fluidized-Bed Demonstration Project: A U.S. DOE post-project assessment.  

National Technical Information Service (NTIS)

This report is a post-project assessment of the Nucla Circulating Fluidized-Bed (CFB) Demonstration Project, the second project to be completed in the DOE Clean Coal Technology Program. Nucla was the first successful utility repowering project in the US, ...

1995-01-01

351

Cost Estimate of Fluidized Bed Combustor Air Heater for Gas Turbines. Final Report.  

National Technical Information Service (NTIS)

This program consisted of a study of the performance, design concept and capital cost of an unconventional coal-burning, gas turbine, electric power generation system including an indirect-fired air heater in the form of a pressurized fluidized bed (PFB) ...

R. Schaefer

1979-01-01

352

Modeling carbonizing process in fluidized bed  

NASA Astrophysics Data System (ADS)

This paper presents possibility of using neural networks model for designing carbonizing process in fluidized bed. This process is very complicated and difficult as multi-parameters changes are non linear and car drive cross structure is non homogeneous. This fact and lack of mathematical algorithms describing this process makes modeling properties of drives elements by traditional numerical methods difficult or even impossible. In this case it is possible to try using artificial neural network. Using neural networks for modeling carbonizing in fluidized bed is caused by several nets' features: non linear character, ability to generalize the results of calculations for data out of training set, no need for mathematical algorithms describing influence changes input parameters on modeling materials properties. The neural network structure is designed and special prepared by choosing input and output parameters of process. The method of learning and testing neural network, the way of limiting nets structure and minimizing learning and testing error are discussed. Such prepared neural network model, after putting expected values of car cross driving properties in output layer, can give answers to a lot of questions about running carbonizing process in fluidized bed. The practical implications of the neural network models are possibility of using they to build control system capable of on-line controlling running process and supporting engineering decision in real time. The originality of this research is different conception to obtain foreseen materials properties after carbonizing in fluidized bed. The specially prepared neural networks model could be a help for engineering decisions and may be used in designing carbonizing process in fluidized bed as well as in controlling changes of this process.

Szota, M.; Jasinski, J.

2010-06-01

353

Flash Hydrogenation of Coal.  

National Technical Information Service (NTIS)

The patent application describes a process for the hydrogenation of coal comprising the contacting of powdered coal with hydrogen in a rotating fluidized bed reactor. A rotating fluidized bed reactor suitable for use in this process is also disclosed. The...

B. Manowitz M. Steinberg T. V. Sheehan W. E. Winsche C. J. Raseman

1974-01-01

354

Fluidized-Bed Combustion Development: Volume 1, Industrial Steam Generation: Final Report.  

National Technical Information Service (NTIS)

In 1986 Stearns Catalytic performed a study for the US Department of Energy to investigate methodology for improving the economics of atmospheric fluidized bed combustion (AFBC). This report is a result of Phase 1 of this program. The scope of this work i...

B. N. Gaglia R. L. Claussen

1986-01-01

355

ALTERNATIVES TO CALCIUM-BASED SO2 SORBENTS FOR FLUIDIZED-BED COMBUSTION: CONCEPTUAL EVALUATION  

EPA Science Inventory

The report gives results of a conceptual engineering evaluation to screen supported metal oxides as alternatives to natural calcium-based sorbents (limestones and dolomites) for SO2 control in atmospheric and pressurized fluidized-bed combustion (FBC) processes. Alternative sorbe...

356

REGENERATION OF CALCIUM-BASED SO2 SORBENTS FOR FLUIDIZED-BED COMBUSTION: ENGINEERING EVALUATION  

EPA Science Inventory

The report gives results of an engineering evaluation of regeneration of calcium-based SO2 sorbents (limestone and dolomite) for application in both atmospheric and pressurized fluidized-bed combustion (FBC) processes. Economics of FBC power plants, operated with regeneration, ar...

357

TECHNOLOGY ASSESSMENT REPORT FOR INDUSTRIAL BOILER APPLICATIONS: FLUIDIZED-BED COMBUSTION  

EPA Science Inventory

The report gives results of an assessment of the applicability of atmospheric fluidized-bed combustion (AFBC) to industrial boilers. It is one of a series of reports to aid in determining the technological basis for a New Source Performance Standard for air pollutant emissions fr...

358

Transitional behavior in gas-fluidized beds  

NASA Astrophysics Data System (ADS)

Examined at the macro-scale, fluidized beds may appear to behave like a solid, a liquid or a gas, depending on the magnitude of the applied superficial gas velocity. Using DEM simulations, the paper examines the different types of behavior as the gas velocity is increased to cover the complete range from fixed bed to homogeneous expansion, bubbling, turbulent and fast fluidization. The paper highlights the transitions between the various regimes.

Thornton, Colin; Yang, Fang; Seville, Jonathan

2013-06-01

359

Particle pressures in fluidized beds. Annual report  

SciTech Connect

Campbell and Wang (1991) showed that the particle pressures in gas-fluidized beds were largely generated by the passage of bubbles. In particular, they showed that the average particle pressure exerted on the side walls scaled with the average size of the bubble. This immediately brings to mind two questions: (1) what is it about bubbles that leads to particle pressure generation and (2) would there be measurable particle pressures in liquid-fluidized beds which, while unstable, do not bubble? This project is largely aimed at answering these two questions. To attack the first problem, the authors have built a two-dimensional gas-fluidized bed into which bubbles may be injected and the distribution of particle-pressure measured. For the latter, other experiments are being performed in liquid fluidized beds. However, it soon became apparent that the particle pressures generated in the liquid beds are extremely small. This has pointed that phase of the research in two directions. The first is the design and construction of a third, and more sensitive, from of the particle pressure transducer. The second approach arose from reflection on what ultimately was the utility of the current research. This led to the development of a generic stability model, in which all modeled terms are left unspecified. From analyzing this model, they have developed an experimental plan that, by measuring the characteristics of voidage disturbances and comparing with the theory, will allow them to back out appropriate values for the modeled terms. The results will not only yield insight into the particle pressure, but also of the fluid drag. The latter results may be used to evaluate common models for these terms.

Campbell, C.S.; Rahman, K.; Hu, X.; Jin, C.

1994-03-01

360

Cluster Dynamics in a Circulating Fluidized Bed  

SciTech Connect

A common hydrodynamic feature in industrial scale circulating fluidized beds is the presence of clusters. The continuous formation and destruction of clusters strongly influences particle hold-up, pressure drop, heat transfer at the wall, and mixing. In this paper fiber optic data is analyzed using discrete wavelet analysis to characterize the dynamic behavior of clusters. Five radial positions at three different axial locations under five different operating were analyzed using discrete wavelets. Results are summarized with respect to cluster size and frequency.

Guenther, C.P.; Breault, R.W.

2006-11-01

361

Single-stage fluidized-bed gasification  

NASA Astrophysics Data System (ADS)

The single-stage fluidized-bed gasification process, in addition to being a simple system, maximizes gas production and allows the economic exploitation of small peat deposits. The objective of this gasification project is to conduct experiments in order to obtain data for designing a single-stage fluidized-bed gasifier, and to evaluate the economics of converting peat to synthesis gas and to SNG by this process. An existing high-temperature and high-pressure process development unit (PDU) was modified to permit the direct feeding of peat to the fluidized bed. Peat flows by gravity from the feed hopper through a 6-inch line to the screw-feeder conveyor. From there, it is fed to the bottom tee section of the reactor and transported into the gasification zone. Oxygen and steam are fed through a distributing ring into the reactor. Gasification reactions occur in the annulus formed by the reactor tube and a central standpipe. Peat ash is discharged from the reactor by overflowing into the standpipe and is collected in a solids receiver.

Lau, F. S.; Rue, D. M.; Weil, S. A.; Punwani, D. V.

1982-04-01

362

Pressurized Fluidized Bed Combustion of Sewage Sludge  

NASA Astrophysics Data System (ADS)

A conceptual design of an energy recovering system from sewage sludge was proposed. This system consists of a pressurized fluidized bed combustor, a gas turbine, and a heat exchanger for preheating of combustion air. Thermal efficiency was estimated roughly as 10-25%. In order to know the combustion characteristics of the sewage sludge under the elevated pressure condition, combustion tests of the dry and wet sewage sludge were carried out by using laboratory scale pressurized fluidized bed combustors. Combustibility of the sewage sludge was good enough and almost complete combustion was achieved in the combustion of the actual wet sludge. CO emission and NOx emission were marvelously low especially during the combustion of wet sewage sludge regardless of high volatile and nitrogen content of the sewage sludge. However, nitrous oxide (N2O) emission was very high. Hence, almost all nitrogen oxides were emitted as the form of N2O. From these combustion tests, we judged combustion of the sewage sludge with the pressurized fluidized bed combustor is suitable, and the conceptual design of the power generation system is available.

Suzuki, Yoshizo; Nojima, Tomoyuki; Kakuta, Akihiko; Moritomi, Hiroshi

363

Hydrodynamics and erosion modeling of fluidized bed combustors  

SciTech Connect

Hydrodynamics and erosion of Fluidized Bed Combustors (FBCs) containing tubes have been analyzed through the use of the hydrodynamic model, which has been developed at New York University, utilizing a CRAY Y-MP/832 supercomputer and a CONVEX C210 minisupercomputer. Particle velocity fields and bed dynamics including bubble formation and motion and bed expansion and collapse were analyzed for high pressure cold and hot beds. The cold beds were studied by (a) optimizing tube models for simulating a circular tube, (b) varying the distance from distributor plate to the tubes, (c) changing tube size, and (d) using vertical tubes. Atmospheric and pressurized fluidized bed combustors were also simulated and compared to each other for bubble size, bubble frequencies, particle jets, and tube erosion. In particular, the computation revealed bubble coalescence which causes high particle jets. Threshold velocity has been analyzed utilizing Hertz contact theory and the maximum shear theory (Tresca). Tube erosion was predicted utilizing the Finnie erosion model and the modified Finnie model, which considers the threshold velocity and compared to each other. Computed results show that the distance from distributor to the tubes, tube size, tube orientation and operating pressure have significant effect on bed dynamics and tube erosion. The threshold velocity is found to significantly influence the prediction of erosion.

Li, C.; Zakkay, V. (New York Univ., New York, NY (United States). Dept. of Applied Science)

1994-12-01

364

Fluidized Bed Asbestos Sampler Design and Testing  

SciTech Connect

A large number of samples are required to characterize a site contaminated with asbestos from previous mine or other industrial operations. Current methods, such as EPA Region 10’s glovebox method, or the Berman Elutriator method are time consuming and costly primarily because the equipment is difficult to decontaminate between samples. EPA desires a shorter and less costly method for characterizing soil samples for asbestos. The objective of this was to design and test a qualitative asbestos sampler that operates as a fluidized bed. The proposed sampler employs a conical spouted bed to vigorously mix the soil and separate fine particulate including asbestos fibers on filters. The filters are then analyzed using transmission electron microscopy for presence of asbestos. During initial testing of a glass prototype using ASTM 20/30 sand and clay fines as asbestos surrogates, fine particulate adhered to the sides of the glass vessel and the tubing to the collection filter – presumably due to static charge on the fine particulate. This limited the fines recovery to ~5% of the amount added to the sand surrogate. A second prototype was constructed of stainless steel, which improved fines recovery to about 10%. Fines recovery was increased to 15% by either humidifying the inlet air or introducing a voltage probe in the air space above the sample. Since this was not a substantial improvement, testing using the steel prototype proceeded without using these techniques. Final testing of the second prototype using asbestos suggests that the fluidized bed is considerably more sensitive than the Berman elutriator method. Using a sand/tremolite mixture with 0.005% tremolite, the Berman elutriator did not segregate any asbestos structures while the fluidized bed segregated an average of 11.7. The fluidized bed was also able to segregate structures in samples containing asbestos at a 0.0001% concentration, while the Berman elutriator method did not detect any fibers at this concentration. Opportunities for improvement with the fluidized bed include improving reproducibility among replicates, increasing mass recovery, improving the lid gasket seal.

Karen E. Wright; Barry H. O'Brien

2007-12-01

365

Method of and apparatus for preheating pressurized fluidized bed combustor and clean-up subsystem of a gas turbine power plant  

DOEpatents

In a gas turbine power plant having a pressurized fluidized bed combustor, gas turbine-air compressor subsystem and a gas clean-up subsystem interconnected for fluid flow therethrough, a pipe communicating the outlet of the compressor of the gas turbine-air compressor subsystem with the interior of the pressurized fluidized bed combustor and the gas clean-up subsystem to provide for flow of compressed air, heated by the heat of compression, therethrough. The pressurized fluidized bed combustor and gas clean-up subsystem are vented to atmosphere so that the heated compressed air flows therethrough and loses heat to the interior of those components before passing to the atmosphere.

Cole, Rossa W. (E. Rutherford, NJ); Zoll, August H. (Cedar Grove, NJ)

1982-01-01

366

Erosion of heat exchanger tubes in fluidized beds  

Microsoft Academic Search

This final report describes the activities of the 3-year project entitled Erosion of Heat Exchanger Tubes In Fluidized Beds.'' which was completed at the end of 1990. Project accomplishments include the collection of a substantial body of wear data In a 24in. [times] 24in. fluidized bed, comparative wear results In a 6in. [times] 6in. fluidized bed, the development of a

E. K. Johnson; R. L. C. Flemmer

1991-01-01

367

Fluidized bed reactor having an integrated recycle heat exchanger  

SciTech Connect

This patent describes a fluidized bed combustion system. It includes a furnace, a fluidized bed of combustible particulate material disposed in the furnace, a recycle heat exchanger disposed adjacent the furnace and sharing a common wall with the furnace separating means for receiving a mixture of flue gases and entrained particulate material from a fluidized bed in the furnace and separating the particulate material from the flue gases, means for passing the separated partition disposed in the heat exchanger.

Campbell, W.R.; Alliston, M.G.; Sisson, B.H.

1990-01-30

368

Bed material agglomeration during fluidized bed combustion. Final report  

SciTech Connect

The purpose of this project is to determine the physical and chemical reactions which lead to the undesired agglomeration of bed material during fluidized bed combustion of coal and to relate these reactions to specific causes. A survey of agglomeration and deposit formation in industrial fluidized bed combustors (FBCs) indicate that at least five boilers were experiencing some form of bed material agglomeration. Deposit formation was reported at nine sites with deposits most commonly at coal feed locations and in cyclones. Other deposit locations included side walls and return loops. Three general types of mineralogic reactions were observed to occur in the agglomerates and deposits. Although alkalies may play a role with some {open_quotes}high alkali{close_quotes} lignites, we found agglomeration was initiated due to fluxing reactions between iron (II) from pyrites and aluminosilicates from clays. This is indicated by the high amounts of iron, silica, and alumina in the agglomerates and the mineralogy of the agglomerates. Agglomeration likely originated in the dense phase of the FBC bed within the volatile plume which forms when coal is introduced to the boiler. Secondary mineral reactions appear to occur after the agglomerates have formed and tend to strengthen the agglomerates. When calcium is present in high amounts, most of the minerals in the resulting deposits are in the melilite group (gehlenite, melilite, and akermanite) and pyroxene group (diopside and augite). During these solid-phase reactions, the temperature of formation of the melilite minerals can be lowered by a reduction of the partial pressure of CO{sub 2} (Diopside + Calcite {r_arrow}Akermanite).

Brown, R.C.; Dawson, M.R.; Smeenk, J.L.

1996-01-01

369

Formation and decomposition of N 2O in fluidized bed boilers  

Microsoft Academic Search

Emissions of N2O from various coal fired appliances have been measured. The results show that conventional appliances generally emit low levels of N2O [< 30 mg m?3 (STP)]. Fluidized beds usually emit considerably higher levels, due to the lower combustion temperatures prevailing in such plant. In order to study the mechanisms underlying N2O formation and destruction, emissions from coal combustion

Bernhard Bonn; Gudrun Pelz; Herbert Baumann

1995-01-01

370

Parametric performance studies on fluidized-bed heat exchangers. Quarterly technical progress report, 1 January31 March 1982  

Microsoft Academic Search

Analyses and experiments will be performed in this program to investigate the performance of single- and multi-stage shallow fluidized beds for possible application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. Tests will be conducted to (1) investigate the effects of fouling due to liquid condensate in the gas stream on

Stoeffler

1982-01-01

371

Development of second-generation pressurized fluidized bed combustion process  

SciTech Connect

Under the sponsorship of the United States Department of Energy, Foster Wheeler Development Corporation, and its team members, Westinghouse, Gilbert/Commonwealth, and the Institute of Gas Technology are developing second-generation pressurized fluidized bed combustion technology capable of achieving net plant efficiency in excess of 45 percent based on the higher heating value of the coal. A three-phase program entails design and costing of a 500 MWe power plant and identification of developments needed to commercialize this technology (Phase 1), testing of individual components (Phase 2), and finally testing these components in an integrated mode (Phase 3). This paper briefly describes the results of the first two phases as well as the progress on the third phase. Since other projects which use the same technology are in construction or in negotiation stages -- namely, the Power System Development Facility and the Four Rivers Energy Modernization Projects -- brief descriptions of these are also included.

Wolowodiuk, W.; Robertson, A. [Foster Wheeler Development Corp., Livingston, NJ (United States); Bonk, D. [USDOE Morgantown Energy Technology Center, WV (United States)

1994-10-01

372

Exergy method of power plant systems analysis and its application to a pressurized fluidized bed coal-fired combined-cycle power plant  

SciTech Connect

This thesis surveys the concepts of exergy and extends the exergy method of analysis from the standpoint of its applications to the power plant systems. After a brief historical review of exergy concepts, the general exergy equation is derived from the combined equation of First and Second Law, and it is shown that any special case of exergy equation is a simplified form of the general exergy equation. The mathematical method for the exergy analysis of a steady-state, steady-flow system, analogous to that of the First Law, is given. The exergy losses in a power plant are discussed. Then in order to examine these losses, the Second Law performance of major processes of combustion, compression, heat transfer, mixing and throttling have been analyzed analytically, and the exergy efficiencies are defined that accurately assess the thermodynamic performance of the corresponding processes. The methods for computation of exergy loss and exergy efficiency are given and simplified for practical cases of the corresponding processes. Analytical methods for evaluating the exergy of coal, pure substances (air and water), and combustion gases are presented and the energy-exergy tables for corresponding working substances are constructed. Finally, a comprehensive thermodynamic analysis, with emphasis on the Second Law (exergy) consideration, of an actual coal-fired, combined-cycle (CFCC) power plant, being designed by the General Electric Company, is carried out and suggestions are made as to what (and where), if any, improvement might be made in the design.

Ghamarian, A.

1981-01-01

373

Transients in a circulating fluidized bed boiler  

NASA Astrophysics Data System (ADS)

Transients in a circulating fluidized bed boiler firing biomass are considered. An attempt is made to describe transients with the use of concepts applied in the automatic control theory. The parameters calculated from an analysis of unsteady heat balance equations are compared with the experimental data obtained in the 12-MW boiler of the Chalmers University of Technology. It is demonstrated that these equations describe the transient modes of operation with good accuracy. Dependences for calculating the time constants of unsteady processes are obtained.

Baskakov, A. P.; Munts, V. A.; Pavlyuk, E. Yu.

2013-11-01

374

Gas fluidized-bed stirred media mill  

DOEpatents

A gas fluidized-bed stirred media mill is provided for comminuting solid ticles. The mill includes a housing enclosing a porous fluidizing gas diffuser plate, a baffled rotor and stator, a hollow drive shaft with lateral vents, and baffled gas exhaust exit ports. In operation, fluidizing gas is forced through the mill, fluidizing the raw material and milling media. The rotating rotor, stator and milling media comminute the raw material to be ground. Small entrained particles may be carried from the mill by the gas through the exit ports when the particles reach a very fine size.

Sadler, III, Leon Y. (Tuscaloosa, AL)

1997-01-01

375

Spatiotemporal dynamics of a shallow fluidized bed.  

SciTech Connect

An experimental and theoretical study of the dynamics of an air-fluidized thin granular layer is presented. Near the threshold of instability, the system exhibits critical behavior with remarkably long transient dynamics. Above the threshold of fluidization the system undergoes a Hopf bifurcation as the layer starts to oscillate at a certain frequency due to a feedback between the layer dilation and the airflow rate. Based on our experimental data, we formulate a the simple dynamical model which describes the transition in a shallow fluidized bed.

Aranson, I. S.; Tsimring, L. S.; Clark, D. K.

2000-12-05

376

The fluidized bed electrowinning of silver  

NASA Astrophysics Data System (ADS)

Fluidized bed electrowinning appears to be an alternative to the Zadra cell usually employed to deposit silver electrolytically from cyanide solutions. By using a bench scale cell it was found that when using either pure silver or silver coated copper particles such electrowinning could be carried out without operating problems and with reasonable current efficiency and cell voltage. Various anodes, for use in the cell, were examined and three found to be satisfactory. By electrolyte analysis and by EDAX analysis of the silver deposit, the silver was shown to be free of impurities down to the detection level of the analyses.

Huh, T.; Evans, J. W.; Carey, C. D.

1983-09-01

377

Fluidized bed adsorption of cephalosporin C.  

PubMed

Fluidized bed adsorption can substantially simplify the recovery of products from fermentation. There are, however, several critical parameters, which have a significant influence on the performance of such systems. This paper presents experimental results on the adsorption of an antibiotic, Cephalosporin C, on macroporous adsorbents of the polystyrene type and on an ion exchanger. Internals (static mixers) were used to control bed expansion and mixing, the range of flow rates could thus be extended significantly. An integrated mathematical model was developed comprising bed expansion, residence time distribution and mixing, adsorption kinetics and equilibria. PMID:11755989

Hicketier, M; Buchholz, K

2002-02-28

378

System design study to reduce capital and operating costs and bench-scale testing of a circulating-bed AFB [atmospheric pressure fluidized bed] advanced concept: Phase 1, Design, cost estimate, and cost comparison for MWK circulating fluid bed combustor and oil-fired boilers: Final report  

SciTech Connect

The Department of Energy (DOE) issued an RFP for a "System Design Study to Reduce Capital and Operating Cost and Bench Scale Testing of a Circulating-Bed AFB Advanced Concept." The design and cost study of a 150,000 pounds per hour steam boiler comprised Phase-I of the RFP. The objective was to produce a design with improved performance and reduced capital and operating costs compared with conventional atmospheric pressure fluidized bed (AFB) boilers. The final result was a significant reduction of capital cost - 36% below the lowest AFB plant cost. The steam cost was 24% below the corresponding cost for the AFB process. In June 1985, DOE issued a Change Order (C001) to the Phase-I study in order for MWK to design and estimate the cost for a scaled-down coal-fired (Illinois No. 6, 3% S) CFBC plant producing low pressure and low temperature steam (75,000lbs/hr, 200 psig, 387{degree}F), and to compare the costs -capital and steam costs -with those for a packaged high sulfur (3%) fuel oil-fired boiler, which is of the same capacity and requires SO{sub 2} removal. An additional objective was to estimate the cost for a No. 2 fuel oil-fired boiler that does not need any SO{sub 2} scrubber. An evaluation of the sensitivity of the steam cost to the oil-fired boiler capital cost and to fuel prices was also to be undertaken. The cost of steam produced by the No. 6 fuel oil boiler is 52% higher than the cost for CFBC, and the corresponding cost for the No. 2 fuel oil plant is 43% higher. Again, a large advantage for the CFBC comes from the low price of coal relative to that of oil. The large cost advantage of steam calculated for the MWK CFBC using coal as a fuel over the oil-fired boilers would remain even in the worst case scenario of a declining oil price accompanied by a steady coal price. 7 refs., 25 figs., 34 tabs.

Sadhukhan, P.; Lin, Y.Y.; Hsiao, K.H.; Richards, S.R.; Wagner, C.; Settle, W.H.; Bryant, J.; Gorman, W.A.; Newlin, T.; Shires, P.J.; James, J.L.

1986-06-01

379

Microwave-heated fluidized bed reactor having stages  

SciTech Connect

An improvement is claimed for introducing into the fluidized-bed heating reactor a water-containing substance to be treated such as an uranyl nitrate solution and subjecting the substance to heat treatment. The reactor of the invention is provided with a microwave-generating means for applying microwaves to the fluidized bed and thereby heating the same.

Nakamori, Y.; Kubota, T.; Matsumura, T.

1984-10-09

380

Fluidized bed combustion and desulfurization of a heavy liquid fuel  

Microsoft Academic Search

An experimental and theoretical study on the combustion and desulfurization of liquid fuels in fluidized beds is proposed in the paper.Tests with a high sulfur liquid fuel (Egyptian mazut) have been performed in a bubbling fluidized bed combustor equipped with a special fuel injector at different operating conditions. Limestone is used as sorbent at various Ca\\/S ratio. The experiments evidenced

Francesco Miccio; Farouk M. Okasha

2005-01-01

381

Theoretical study of fluidized-bed drying with microwave heating  

Microsoft Academic Search

A mathematical model of heat and mass transfer is developed for fluidized-bed drying with microwave heating. The numerical results show that the temperature is uniformly distributed within a particle and that the pressure distribution in the particle has a significant effect on microwave fluidized-bed drying. The electric field strength E is an important parameter affecting the magnitude and distribution of

Zhao Hui Wang; Guohua Chen

2000-01-01

382

PMB-Waste: An analysis of fluidized bed thermal treatment  

Microsoft Academic Search

A fluidized bed treatment process was evaluated for solid waste from plastic media blasting of aircraft protective coating. The treatment objective is to decompose and oxidize all organic components, and concentrate all the hazardous metals in the ash. The reduced volume and mass are expected to reduce disposal cost. A pilot test treatment was done in an existing fluidized bed

U. Gat; M. D. Kass; D. B. Lloyd

1995-01-01

383

Hydrodynamic Characterization of 3D Fluidized Beds Using Noninvasive Techniques  

Microsoft Academic Search

Fluidized beds are useful processing systems that are employed by many industries for their relatively unique operating properties. Low pressure drops, uniform temperature distributions, and high heat\\/mass transfer rates occur through the action of vertical gas injection into a column of solid particles. Although these properties give fluidized beds great advantages over other processing systems, the hydrodynamic characterization of fluidized

Joshua Drake

2011-01-01

384

Fluid dynamics of a fluidized bed packed with heat exchangers  

Microsoft Academic Search

Tests of two fluidized bed facilities are described. Bed dynamics of a one foot gas fired fluidized bed (GFFB) and its interrelation with the heat transfer characteristics of immersed heat exchangers of different configurations were studied. The GFFB, capable of achieving different gas velocity distributions in the bed with the help of a specially designed gas distributor, was operated to

V. Zakkay; G. Miller; A. Kolar; J. Franceschi; S. Panunzio; W. Skelley; C. C. Ho; A. Brentan; G. Kiviat; S. Rosen

1981-01-01

385

Fluidized bed heat exchanger utilizing angularly extending heat exchange tubes  

Microsoft Academic Search

A fluidized bed heat exchanger in which air is passed through a bed of particulate material containing fuel disposed in a housing. A steam\\/water natural circulation system is provided and includes a steam drum disposed adjacent the fluidized bed and a series of tubes connected at one end to the steam drum. A portion of the tubes are connected to

Fred M. Talmud; Juan-Antonio Garcia-Mallol

1980-01-01

386

Investigation of waste heat recovery utilizing fluidized bed heat exchangers  

Microsoft Academic Search

An experimental and analytical investigation was conducted to evaluate the economic potential of shallow fluidized bed heat exchangers to recover the waste heat in the exhaust gases from large diesel engines. The program involved: (1) experiments to measure the heat transfer, pressure loss, and fouling characteristics of a commercially available shallow fluidized bed heat exchanger, and (2) conceptual design of

1978-01-01

387

Continuous Cleaning of Heat Exchanger with Recirculating Fluidized Bed  

Microsoft Academic Search

Fluidized bed heat exchangers for liquids have been studied in the United States, the Netherlands, and the Federal Republic of Germany. Between 1965 and 1970, fluidized bed heat exchangers were developed in the United States as brine heaters in seawater desalination. Furthermore, their potential in the utilization of geothermal energy was tested between 1975 and 1980. In the Netherlands, fluidized

Jochen St. Kollbach; W. Dahm; R. Rautenbach

1987-01-01

388

Some problems of heat exchange in fluidized beds  

Microsoft Academic Search

The use of calorimeters with different degrees of surface blackness to delineate the convective-conductive and radiative components of complex heat exchange is discussed. The effect of surface particle cooling on radiative heat transfer is investigated by reviewing results of various experiments performed in fluidized-bed installations. Heat transfer from the underdense to the dense phase of a fluidized bed by means

A. P. Baskakov; B. V. Berg; Iu. M. Goltsobin; A. M. Dubinin; A. A. Zharkov; G. Ia. Zakharchenko; S. V. Zviagin; O. M. Panov

1976-01-01

389

Pressure Fluctuations as a Diagnostic Tool for Fluidized Beds  

SciTech Connect

The purpose of this project was to investigate the origin of pressure fluctuations in fluidized bed systems. The study assessed the potential for using pressure fluctuations as an indicator of fluidized bed hydrodynamics in both laboratory scale cold-models and industrial scale boilers. Both bubbling fluidized beds and circulating fluidized beds were evaluated. Testing including both cold-flow models and laboratory and industrial-scale combustors operating at elevated temperatures. The study yielded several conclusions on the relationship of pressure fluctuations and hydrodynamic behavior in fluidized beds. The study revealed the importance of collecting sufficiently long data sets to capture low frequency (on the order of 1 Hz) pressure phenomena in fluidized beds. Past research has tended toward truncated data sets collected with high frequency response transducers, which miss much of the spectral structure of fluidized bed hydrodynamics. As a result, many previous studies have drawn conclusions concerning hydrodynamic similitude between model and prototype fluidized beds that is insupportable from the low resolution data presented.

Ethan Bure; Joel R. Schroeder; Ramon De La Cruz; Robert C. Brown

1998-05-01

390

THE EXPERIMENTAL STUDY OF ROTARY-STREAM FLUIDIZED BED DRYING  

Microsoft Academic Search

Rotary-stream fluidized bed drying is the combination of fluidized bed drying and pneumatic drying. Both non-viscous and viscous materials and even sticky paste can be dried successfully with this technique. The material being processed is turned to powder or granular product of controlled homogeneous in one treatment and no further pulverization is necessary. Correlation of Eu vs Re and Nu

Quin Shu-De; Gu Fang-Zhen

1993-01-01

391

Phosphate removal in a fluidized bed—II. Process optimization  

Microsoft Academic Search

The aggregation of fine primarily formed calcium phosphate particles with sand grains in a fluidized bed for phosphate removal was studied experimentally by means of a set-up which isolated aggregation from other processes during calcium phosphate precipitation, as well as through experiments under normal operation of the fluidized bed. The net aggregation process was described by means of a mathematical

M. M. Seckler; M. L. J. van Leeuwen; O. S. L. Bruinsma; G. M. van Rosmalen

1996-01-01

392

Baffle effects on performance of catalytic circulating fluidized bed reactor  

Microsoft Academic Search

This paper reports on baffle effects on the performance of a catalytic circulating fluidized bed reactor which were examined experimentally. The circulating fluidized bed reactor or riser was 102 mm in diameter and 6.32 m in height. Reaction was the catalytic decomposition of ozone using FCC particles with a mean diameter of 89 [mu]m, impregnated with ferric oxide as catalysts.

Peijun Jiang; Hsiaotao Bi; Rong-Her Jean; Liang-Shih Fan

1991-01-01

393

Bubble size reduction in electric-field-enhanced fluidized beds  

Microsoft Academic Search

Fluidized beds are a common form of a chemical reactor, in which a deep layer of solid particles is set in motion by a stream of gas blowing upward. However, the appearance of gas bubbles can significantly limit the selectivity, conversion, and product properties of gas–solid fluidized beds. We present results on the application of low-intensity electric fields in fluidized

F. Kleijn van Willigen; J. R. van Ommen; J. van Turnhout; C. M. van den Bleek

2005-01-01

394

Fluidized bed air-to-air heat pump evaporator evaluation  

NASA Astrophysics Data System (ADS)

Frost formation of air-to-air heat pump evaporator surfaces reduces unit efficiency and restricts application. The use of a fluidized bed heat exchanger as an air-to-heat pump evaporator was investigated to determine if frost accumulation could be eliminated. Experimental investigations were conducted and the following results obtained: (1) frost accumulation was insignificant with fluidized bed temperatures below 32 F and (2) moisture accumulation from condensation resulted in unstable fluidized bed operation when the fluidized bed temperature was above 32 F. Several concepts - maintenance bed temperature below 32 F, reverse refrigerant flow, air-dry bed, nonadhering bed material, and ultrasonics - to solve the moist bed problem were evaluated, with no practical solution being developed. The use of a fluidized bed heat exchanger for air-to-air heat pump evaporators was determined not feasible.

Ashley, J. L.

1983-07-01

395

Fluidized bed gasification of select granular biomaterials.  

PubMed

Biomaterials can be converted into solid, liquid and gaseous fuels through thermochemical or biochemical conversion processes. Thermochemical conversion of granular biomaterials is difficult because of its physical nature and one of the suitable processes is fluidized bed gasification. In this study, coir pith, rice husk and saw dust were selected and synthetic gas was generated using a fluidized bed gasifier. Gas compositions of product gas were analyzed and the percentage of carbon monoxide and carbon dioxide was in the range of 8.24-19.55 and 10.21-17.14, respectively. The effect of equivalence ratio (0.3, 0.4 and 0.5) and reaction time (at 10 min interval) on gas constituents was studied. The gas yield for coir pith, rice husk and sawdust were found to be in the range of 1.98-3.24, 1.79-2.81 and 2.18-3.70 Nm3 kg(-1), respectively. Models were developed to study the influence of biomaterial properties and operating conditions on molar concentration of gas constituents and energy output. PMID:20817445

Subramanian, P; Sampathrajan, A; Venkatachalam, P

2010-08-11

396

Electrically enhanced fluidized bed heat exchanger  

SciTech Connect

The experiments have shown that a high level of electrical charging can be achieved in a fluidized bed of two resistive particle types; that bed stabilization rather than increased sensible heat transport dominates low frequency electric field effects on heat transfer with most bed loadings; and, hence, that applying an oscillatory potential difference between tubes or rods in a fluidized bed of two mutual contact-charging particle species gives reduced rather than improved heat transfer. Applying an oscillatory potential difference between rods in a bed of quartz particles fluidized alone did give improved heat transfer, however. With no electric field applied, most fluidized mixes were found to give higher heat transfer rates than the average of the values when each of the two species was fluidized alone. The high level of charging observed in some mixed beds may prove of interest for some air cleanup applications; the results show that simultaneous fluidization of pairs of bipolar charging materials of similar particle size is possible without excessive agglomeration. This would be important for air cleanup.

Lessor, D.L.; Robertus, R.J.; Roberts, G.L.

1994-05-01

397

Predictive models of circulating fluidized bed combustors  

SciTech Connect

Steady flows influenced by walls cannot be described by inviscid models. Flows in circulating fluidized beds have significant wall effects. Particles in the form of clusters or layers can be seen to run down the walls. Hence modeling of circulating fluidized beds (CFB) without a viscosity is not possible. However, in interpreting Equations (8-1) and (8-2) it must be kept in mind that CFB or most other two phase flows are never in a true steady state. Then the viscosity in Equations (8-1) and (8-2) may not be the true fluid viscosity to be discussed next, but an Eddy type viscosity caused by two phase flow oscillations usually referred to as turbulence. In view of the transient nature of two-phase flow, the drag and the boundary layer thickness may not be proportional to the square root of the intrinsic viscosity but depend upon it to a much smaller extent. As another example, liquid-solid flow and settling of colloidal particles in a lamella electrosettler the settling process is only moderately affected by viscosity. Inviscid flow with settling is a good first approximation to this electric field driven process. The physical meaning of the particulate phase viscosity is described in detail in the chapter on kinetic theory. Here the conventional derivation resented in single phase fluid mechanics is generalized to multiphase flow.

Gidaspow, D.

1992-07-01

398

Second-Generation Pressurized Fluidized Bed Combustion: Small gas turbine industrial plant study  

Microsoft Academic Search

Second-Generation Pressurized Fluidized Bed Combustion (PFBC) plants provide a coal-fired, high-efficiency, combined-cycle system for the generation of electricity and steam. The plants use lime-based sorbents in PFB combustors to meet environmental air standards without back-end gas desulfurization equipment. The second-generation system is an improvement over earlier PFBC concepts because it can achieve gas temperatures of 2100°F and higher for improved

J. Shenker; R. Garland; D. Horazak; F. Seifert; R. Wenglarz

1992-01-01

399

Air void system in concrete containing circulating fluidized bed combustion fly ash  

Microsoft Academic Search

The increased use of advanced coal-burning technologies for power generation, such as circulating fluidized bed combustion\\u000a (CFBC), results in new waste products. The potential for using CFBC fly ash in air-entrained concrete was investigated in\\u000a order to assess the influence of CFBC fly ash on the microstructure of air voids in hardened concrete. A special specimen\\u000a surface preparation technique for

Michal A. Glinicki; Marek Zielinski

2008-01-01

400

Second-generation pressurized fluidized bed combustion plant commercialization plan: Task 4 report  

Microsoft Academic Search

This report presents a plan for moving coal-fired second-generation pressurized fluidized bed (PFB) combustion plants from their present conceptual stage to and through the sale of the first commercial electric utility plant by 2000; market penetration analyses are also included. A second-generation PFB plant can operate with an efficiency of 45 percent (based on the higher heating value of the

J. H. Hirschenhofer; A. S. Robertson

1989-01-01

401

Steam hydration of sorbents from a dual fluidized bed CO 2 looping cycle reactor  

Microsoft Academic Search

Results are presented on steam hydration of spent residues obtained from a 75kWth dual fluidized bed combustion (FBC) pilot plant unit operating in a CO2 looping cycle mode. The samples were collected from the unit under various conditions, which included electrical heating of the reactor, as well as firing with coal, and biomass under oxy-fuel combustion conditions. In addition, different

Vasilije Manovic; Dennis Lu; Edward J. Anthony

2008-01-01

402

Industrial application of fluidized bed combustion. Progress report, January-September 1983  

SciTech Connect

Work accomplished during a shut-down of the industrial fluidized bed (IFB) plant is reported, including: coal receiving and preparation; fuel feed system work; progress on boiler and gas side equipment. After completion of construction work and acid cleaning, the boiler was restarted. The performance of specific plant equipment during shakedown operation is reported. The performance of specific plant equipment during shakedown operation is reported. Operator training classes were conducted, and the final revision of a test plan was completed. (LEW)

Not Available

1983-01-01

403

Cost estimate of fluidized bed combustor air heater for gas turbines. Final report  

Microsoft Academic Search

This program consisted of a study of the performance, design concept and capital cost of an unconventional coal-burning, gas turbine, electric power generation system including an indirect-fired air heater in the form of a pressurized fluidized bed (PFB) operating near stoichiometric fuel\\/air ratios. The system has two special features. One is the use in a turbine of clean air heated

1979-01-01

404

Heat transfer in freeboard region of fluidized beds  

SciTech Connect

This research involved the study of heat transfer and fluid mechanic characteristics around a horizontal tube in the freeboard region of fluidized beds. Heat transfer coefficients were experimetnally measured for different bed temperatures, particle sizes, gas flow rates, and tube elevations in the freeboard region of air fluidized beds at atmospheric pressure. Local heat transfer coefficients were found to vary significantly with angular position around the tube. Average heat transfer coefficients were found to decrease with increasing freeboard tube elevation and approach the values for gas convection plus radiation for any given gas velocity. For a fixed tube elevation, heat transfer coefficients generally increased with increasing gas velocity and with high particle entrainment they can approach the magnitudes found for immersed tubes. Heat transfer coefficients were also found to increase with increasing bed temperature. It was concluded that this increase is partly due to increase of radiative heat transfer and partly due to change of thermal properties of the fluidizing gas and particles. To investigate the fluid mechanic behavior of gas and particles around a freeboard tube, transient particle tube contacts were measured with a special capacitance probe in room temperature experiments. The results indicated that the tube surface experiences alternating dense and lean phase contacts. Quantitative information for local characteristics was obtained from the capacitance signals and used to develop a phenomenological model for prediction of the heat transfer coefficients around freeboard tubes. The packet renewal theory was modified to account for the dense phase heat transfer and a new model was suggested for the lean phase heat transfer. Finally, an empirical freeboard heat transfer correlation was developed from functional analysis of the freeboard heat transfer data using nondimensional groups representing gas velocity and tube elevation.

Biyikli, S.; Tuzla, K.; Chen, J.C.

1983-10-01

405

Advanced control strategies for fluidized bed dryers  

SciTech Connect

Generating the best possible control strategy comprises a necessity for industrial processes, by virtue of product quality, cost reduction and design simplicity. Three different control approaches, namely an Input-Output linearizing, a fuzzy logic and a PID controller, are evaluated for the control of a fluidized bed dryer, a typical non-linear drying process of wide applicability. Based on several closed loop characteristics such as settling times, maximum overshoots and dynamic performance criteria such as IAE, ISE and ITAE, it is shown that the Input-Output linearizing and the fuzzy logic controller exhibit a better performance compared to the PID controller tuned optimally with respect to IAE, for a wide range of disturbances; yet, the relevant advantage of the fuzzy logic over the conventional nonlinear controller issues upon its design simplicity. Typical load rejection and set-point tracking examples are given to illustrate the effectiveness of the proposed approach.

Siettos, C.I.; Kiranoudis, C.T.; Bafas, G.V.

1999-11-01

406

Fuzzy control of a fluidized bed dryer  

SciTech Connect

Fluidized bed dryers are utilized in almost every area of drying applications and therefore improved control strategies are always of great interest. The nonlinear character of the process, exhibited in the mathematical model and the open loop analysis, implies that a fuzzy logic controller is appropriate because, in contrast with conventional control schemes, fuzzy control inherently compensates for process nonlinearities and exhibits more robust behavior. In this study, a fuzzy logic controller is proposed; its design is based on a heuristic approach and its performance is compared against a conventional PI controller for a variety of responses. It is shown that the fuzzy controller exhibits a remarkable dynamic behavior, equivalent if not better than the PI controller, for a wide range of disturbances. In addition, the proposed fuzzy controller seems to be less sensitive to the nonlinearities of the process, achieves energy savings and enables MIMO control.

Taprantzis, A.V.; Siettos, C.I.; Bafas, G.V. [National Technical Univ., Athens (Greece). Dept. of Chemical Engineering

1997-05-01

407

Electromechanics of fluidized beds of nanoparticles.  

PubMed

The electromechanical behavior of a gas-fluidized bed of insulating silica nanoparticles is investigated. When fluidized by gas, these nanoparticles form highly porous agglomerates of size of the order of hundreds of microns, which gives rise to a nonbubbling fluidization regime. Bed expansion is enhanced by an imposed alternating electric field for oscillation frequencies in the range between tens and hundreds of hertzs and field strengths of about 1 kV/cm . Nanoparticle agglomerates are naturally charged and experience forced oscillations that cause an increase of the gas flow shear on their surface. As a consequence, the agglomerate size is expected to decrease, which can explain the observed behavior. A model based on the balance between attractive and flow shear forces is presented that accounts for agglomerate size reduction as the strength of the field is increased. PMID:19257027

Espin, M J; Valverde, J M; Quintanilla, M A S; Castellanos, A

2009-01-27

408

ESTABLISHMENT OF AN ENVIRONMENTAL CONTROL TECHNOLOGY LABORATORY WITH A CIRCULATING FLUIDIZED-BED COMBUSTION SYSTEM  

SciTech Connect

The purpose of this report is to summarize the progress made on the project ''Establishment of an Environmental Control Technology Laboratory with a Circulating Fluidized-Bed Combustion (CFBC) System'' in this quarter (September-December of 2003). The main tasks in this quarter consisted of the following four parts. First, all documents for managing this project have been prepared and sent to the Office of Project Management at the US Department of Energy's (DOE's) National Energy Technology Laboratory (NETL). Second, plans for the renovation of space for a new combustion laboratory for the CFBC system has progressed smoothly. Third, considerable progress in the design of the CFBC system has been made. Finally, a lab-scale simulated fluidized-bed combustion facility has been set up in order to make some fundamental investigations of the co-firing of coal with waste materials in the next quarter. Proposed work for the next quarter has been outlined in this report.

Wei-Ping Pan; Kunlei Liu; John T. Riley

2004-01-01

409

Hot gas heat exchanger fired from the fluidized bed wood combustor  

Microsoft Academic Search

An atmospheric fluidized-bed combustor hot gas heat exchanger system has operated in Green Bay, WI since the spring of 1983. The system burns 50% moisture wood residue, and provides nearly 100 MM BTU\\/hour of clean process air at 100 deg. F. for a paper dryer. The gas-to-air heat exchanger receives hot, dirty exhaust gas at 1800 deg. F. directly from

1985-01-01

410

Synthesis gas formation by catalytic oxidation of methane in fluidized bed reactors  

Microsoft Academic Search

The production of synthesis gas (CO + H[sub 2]) by the catalytic partial oxidation of CH[sub 4] in air or O[sub 2] in static fluidized beds at atmospheric pressure has been examined over Pt, Rh, and Ni catalysts coated on 100-[mu]m [alpha]-Al[sub 2]O[sub 3] beads. With CH[sub 4]\\/air feeds, CO and H[sub 2] selectivities as high as 95% with >90%

S. S. Bharadwaj; L. D. Schmidt

1994-01-01

411

Activation of olive-seed waste residue using CO 2 in a fluidized-bed reactor  

Microsoft Academic Search

Physical activation of olive-seed waste residue was carried out under N2\\/CO2 atmosphere in a fluidized-bed reactor system. The effects of activation temperature, activation time and particle size on both yield and quality of the prepared products were studied. The quality was measured in terms of iodine number and adsorptive capacity towards methylene blue dye. In general, it was found that

T. T. Al-Khalid; N. M. Haimour; S. A. Sayed; B. A. Akash

1998-01-01

412

Sulphation and carbonation properties of hydrated sorbents from a fluidized bed CO 2 looping cycle reactor  

Microsoft Academic Search

Sulphation and carbonation have been performed on hydrated spent residues from a 75kWth dual fluidized bed combustion (FBC) pilot plant operating as a CO2 looping cycle unit. The sulphation and carbonation tests were done in an atmospheric pressure thermogravimetric analyzer (TGA), with the sulphation performed using synthetic flue gas (0.45% SO2, 3% O2, 15% CO2 and N2 balance). Additional tests

Vasilije Manovic; Edward J. Anthony; Dennis Y. Lu

2008-01-01

413

Alexandria fluidized-bed process development unit: cold-mode testing  

SciTech Connect

The objectives of the current test program include: validation of predictions from the Massachusetts Institute of Technology (MIT) Coal Atmospheric Fluidized Bed Combustor System Model; experimental studies supporting AFBC process developments; and the collection of transient data for process control design. This topical report summarizes results from cold mode testing, i.e., experiments performed without combustion for MIT Model verification. During these tests, sulfated limestone (generated from normal AFBC operations) was fluidized with air at temperatures ranging from 80 to 500/sup 0/F in the 3' x 3' (nominal) size PDU at Alexandria, VA. The MIT Model predictions tested include: slumped bed height, minimum fluidization velocity, and expanded bed height. In all cases, there were large discrepancies between the Model predictions and corresponding experimental results. Other results obtained included solids size distribution and particle size profiles in the bed. Size distribution was adequately modeled by the Rosin-Rammler equation. No transient process data was collected due to hardware problems with the Data Acquisition System. Tests were also performed to determine the effect of maldistribution of air, caused by leaks in the air distributor, on experimental results. The data indicated that effects of these leaks seemed to be undetectable.

None

1981-02-01

414

AFBAH-a Coal Combustor for GT Cogeneration systems  

Microsoft Academic Search

An atmospheric fluidized bed air heater (AFBAH) system is a means of heating the air in a gas turbine cycle to use the energy for cogeneration. A study called the Coal Combustor for Cogeneration (CCC) indicates that coal-fired cogeneration is a viable concept. A hypothetical reference plant is set up and the major components and gas flow path of the

P. Berman; R. Gorrell; B. Maxwell

1983-01-01

415

Proceedings of the sixth international conference on fluidized bed combustion. Volume II. Technical sessions  

SciTech Connect

The Sixth International Conference on Fluidized Bed Combustion was held April 9-11, 1980, at the Atlanta Hilton, Atlanta, Georgia. It was sponsored by the US Department of Energy, the Electric Power Research Institute, the US Environmental Protection Agency, and the Tennessee Valley Authority. The papers covered recent developments in atmospheric and pressurized fluidized-bed combustion, especially the design, operation and control of pilot and demonstration plants. The cleanup of combustion products and the erosion, corrosion and fouling of gas turbines was emphasized also. Fifty-five papers from Volume 2 of the proceedings have been entered individually into EDB and ERA; five papers had been entered previously from other sources. (LTN)

none,

1980-08-01

416

Computational Fluid Dynamics Simulation of Fluidized Bed Polymerization Reactors.  

National Technical Information Service (NTIS)

Fluidized beds (FB) reactors are widely used in the polymerization industry due to their superior heat- and mass-transfer characteristics. Nevertheless, problems associated with local overheating of polymer particles and excessive agglomeration leading to...

R. Fan

2006-01-01

417

21 CFR 890.5160 - Air-fluidized bed.  

Code of Federal Regulations, 2013 CFR

...Identification. An air-fluidized bed is a device employing the circulation of filtered air through ceramic spherules (small, round ceramic objects) that is intended for medical purposes to treat or prevent bedsores, to treat severe or...

2013-04-01

418

Liquid-Fluidized-Bed Heat Exchanger Flow Distribution Models.  

National Technical Information Service (NTIS)

Allied Chemical Corporation at the Idaho National Engineering Laboratory is developing liquid-fluidized-bed shell-and-tube heat exchangers for geothermal applications. Sand fluidized by geothermal water on the shell side prevents scaling and increases hea...

L. T. Cole C. A. Allen

1979-01-01

419

Packet model of external heat transfer for a fluidized bed  

NASA Astrophysics Data System (ADS)

A modification is proposed for the packet model of external heat transfer of a fluidized bed. The modified model considers heat exchange between the particles and the gas flowing through the packet formed by the particles.

Borodulya, V. A.; Kovenskii, V. I.

1984-11-01

420

Interfhase pass transfer in a fluidized bed with a packing  

NASA Astrophysics Data System (ADS)

Measurements are made of interphase mass-transfer coefficients in a fluidized bed with small- and medium-volume packings. Our experimental data and material from other studies are generalized on the basis of a proposed model.

Tamarin, A. I.; Goryunov, K. E.

1985-06-01

421

Corrosion assessment in FBC (fluidized-bed combustion) systems.  

National Technical Information Service (NTIS)

Metallic materials selected for the construction of heat exchangers and tube support structure in fluidized-bed combustion (FBC) systems must withstand the dynamic corrosive conditions prevalent in these systems. Oxidation-sulfidation interactions leading...

K. Natesan

1990-01-01

422

Electrical resistance of a fluidized bed of graphite particles  

Microsoft Academic Search

Experimental data on the electrical resistivity of fluidized beds of graphite particles are given. The dependence of the resistivity on the filtration velocity, particle size, temperature of the bed, and position of the electrodes is determined.

A. P. Kozhan; K. E. Makhorin; S. P. Gorislavets

1968-01-01

423

SIMULTANEOUS CAPTURE OF METAL, SULFUR AND CHLORINE BY SORBENTS DURING FLUIDIZED BED INCINERATION. (R826694C697)  

EPA Science Inventory

Metal capture experiments were carried out in an atmospheric fluidized bed incinerator to investigate the effect of sulfur and chlorine on metal capture efficiency and the potential for simultaneous capture of metal, sulfur and chlorine by sorbents. In addition to experimental...

424

Fluidized-bed calciner with combustion nozzle and shroud  

DOEpatents

A nozzle employed as a burner within a fluidized bed is coaxially enclosed within a tubular shroud that extends beyond the nozzle length into the fluidized bed. The open-ended shroud portion beyond the nozzle end provides an antechamber for mixture and combustion of atomized fuel with an oxygen-containing gas. The arrangement provides improved combustion efficiency and excludes bed particles from the high-velocity, high-temperature portions of the flame to reduce particle attrition.

Wielang, Joseph A. (Idaho Falls, ID); Palmer, William B. (Shelley, ID); Kerr, William B. (Idaho Falls, ID)

1977-01-01

425

Flow characteristics in a bubbling fluidized bed at elevated temperature  

Microsoft Academic Search

A bubbling fluidized bed with 0.082 m in diameter and 1.5 m in height was employed to investigate the minimum fluidization velocity and flow dynamics at bed temperature up to 1000°C. Ashes of three sizes (Geldart B) from pressurized fluidized bed boiler were used as fluidization materials. Experiments show that the minimum fluidization velocity decreases with increasing bed temperature. Pressure

Qingjie Guo; Guangxi Yue; Toshiyuki Suda; Junichi Sato

2003-01-01

426

Continuous cleaning of heat exchanger with recirculating fluidized bed  

SciTech Connect

Fluidized bed heat exchangers for liquids have been studied in the United States, the Netherlands, and the Federal Republic of Germany. Between 1965 and 1970, fluidized bed heat exchangers were developed in the United States as brine heaters in seawater desalination. Furthermore, their potential in the utilization of geothermal energy was tested between 1975 and 1980. In the Netherlands, fluidized bed heat exchangers have been developed since 1973 for brine heating and heat recovery in multistage flash evaporators for seawater desalination and, since about 1980, for applications in the process industry. The authors became interested in fluidized bed heat exchangers first in 1978 in connection with wastewater evaporation. The authors emphasize that the results of all these groups were in basic agreement. They can be summarized as follows: 1. The fluidized bed will in many cases maintain totally clean surfaces and neither scaling nor fouling will occur. In cases where even a fluidized bed cannot completely prevent scaling or fouling, the thickness of the layer is controlled. In these cases stable operation maintaining acceptable overall heat transfer coefficients is possible without cleaning. 2. There are always excellent heat transfer coefficients as low superficial velocities of less than ..nu.. < 0.5 m/s. 3. The pressure losses are comparable with those in normal heat exchangers since fluidized bed heat exchangers are mostly operated at low superficial velocities. 4. Feed flow may be varied between 50 and 150% or more of the design feed flow. 5. Erosion is negligible. 6. Fluidized bed particles can be manufactured from all sorts of chemically and mechanically resistant materials, such as sand, glass, ceramics, and metals.

St. Kollbach, J.; Dahm, W.; Rautenbach, R.

1987-01-01

427

Liquid-fluidized-bed heat exchanger flow distribution models  

Microsoft Academic Search

Liquid-fluidized-bed shell-and-tube heat exchangers for geothermal applications are considered. Sand fluidized by geothermal water on the shell side prevents scaling and increases heat transfer coefficients over conventional heat exchangers. Tests conducted on two instrumented fluidized-bed heat exchanger models, constructed primarily of plexiglass, which differ in tube bundle orientation are described. Plexiglass construction allowed visual observation of flow patterns. The vertical

L. T. Cole; C. A. Allen

1979-01-01

428

Collecting aerosol in airflow with a magnetically stabilized fluidized bed.  

PubMed

A magnetically stabilized fluidized bed (MSB) is a highly efficient filter that takes the advantage of both fluidized beds and fixed beds. This paper presents the research to collect aerosol in airflow with a MSB. The filtering model of MSB is established with its parameters including magnetic field intensity, gas superficial velocity, average grain-size, and bed height on the collection efficiency of MSB. The model is verified by experiments. PMID:11723940

Gui, K T; Zhang, H; Shi, M H; Xu, Y Q

2001-10-01

429

Control of bed height in a fluidized bed gasification system  

DOEpatents

In a fluidized bed apparatus a method for controlling the height of the fdized bed, taking into account variations in the density of the bed. The method comprises taking simultaneous differential pressure measurements at different vertical elevations within the vessel, averaging the differential pressures, determining an average fluidized bed density, then periodically calculating a weighting factor. The weighting factor is used in the determination of the actual bed height which is used in controlling the fluidizing means.

Mehta, Gautam I. (Greensburg, PA); Rogers, Lynn M. (Export, PA)

1983-12-20

430

Heat treatment of tool steels in fluidized bed  

Microsoft Academic Search

1.Heating of the steels investigated in a fluidized bed at a temperature of 850° and holding 30 min induces negligible oxidation of the metal with an air input factor of 0.3–0.7.2.Steel 70SKhM isothermally hardened in a fluidized bed can be recommended for the production of farm machinery blades with higher quality than those made at the present time.

A. S. Zayarov; M. F. Rybakova; O. K. Vitt; A. P. Migachev

1977-01-01

431

A model of wood flash pyrolysis in fluidized bed reactor  

Microsoft Academic Search

With a view of exploiting renewable biomass energy as a highly efficient and clean energy, liquid fuel from biomass pyrolysis, called bio-oil, is expected to play a major role in future energy supply. At present, fluidized bed technology appears to have maximum potential in producing high-quality bio-oil. A model of wood pyrolysis in a fluidized bed reactor has been developed.

Zhongyang Luo; Shurong Wang; Kefa Cen

2005-01-01

432

Particle pressures in fluidized beds. First year annual report  

SciTech Connect

This is an experimental project to make detailed measurements of the particle pressures generated in fluidized beds. The focus lies in two principle areas: (1) the particle pressure distribution around single bubbles rising in a two-dimensional gas-fluidized bed and (2) the particle pressures measured in liquid-fluidized beds. This first year has largely been to constructing the experiments The design of the particle pressure probe has been improved and tested. A two-dimensional gas-fluidized bed has been constructed in order to measure the particle pressure generated around injected bubbles. The probe is also being adapted to work in a liquid fluidized bed. Finally, a two-dimensional liquid fluidized bed is also under construction. Preliminary measurements show that the majority of the particle pressures are generated in the wake of a bubble. However, the particle pressures generated in the liquid bed appear to be extremely small. Finally, while not directly associated with the particle pressure studies, some NERSC supercomputer time was granted alongside this project. This is being used to make large scale computer simulation of the flow of granular materials in hoppers.

Campbell, C.S.; Rahman, K.; Hu, X.; Jin, C.; Potapov, A.V.

1992-09-01

433

An in-bed tube bank for a fluidized-bed combustor  

DOEpatents

Fluidized-bed combustors have long been used to facilitate the combustion of low-quality fuels and more recently as a means for the clean burning of coal. In a fluidized-bed combustor fuel is fed into a bed of reactive or inert particulate material while air is injected into the bed and passed up through the bed, causing the bed material to act like a turbulent fluid. Where the combustor is utilized for steam generating one or more boiler tubes are positioned so as to span the bed while submerged in the bed, and as fuel is burned within the bed water is injected into the boiler tubes and heated, thereby generating steam. An in-bed tube bank is described for a fluidized bed combustor. The tube bank of the present invention comprises one or more fluid communicating boiler tubes which define a plurality of selectively spaced boiler tube sections. The tube sections are substantially parallel to one another and aligned in a common plane. The tube bank further comprises support members for joining adjacent tube sections, the support members engaging and extending along a selected length of the tube sections and spanning the preselected space there between 4 figs.

Hemenway, L.F. Jr.

1989-08-08

434

ESTABLISHMENT OF AN ENVIRONMENTAL CONTROL TECHNOLOGY LABORATORY WITH A CIRCULATING FLUIDIZED-BED COMBUSTION SYSTEM  

SciTech Connect

This purpose of this report is to present the progress made on the project ''Establishment of an Environmental Control Technology Laboratory (ECTL) with a Circulating Fluidized-Bed Combustion (CFBC) System'' during the period April 1, 2005 through June 30, 2005. The following tasks have been completed. First, the new Combustion Laboratory was occupied on June 15, 2005, and the construction of the Circulating Fluidized-Bed (CFB) Combustor Building is in the final painting stage. Second, the fabrication and manufacturing contract for the CFBC Facility was awarded to Sterling Boiler & Mechanical, Inc. of Evansville, Indiana. Sterling is manufacturing the assembly and component parts of the CFBC system. The erection of the CFBC system is expected to start September 1, 2005. Third, mercury emissions from the cofiring of coal and chicken waste was studied experimentally in the laboratory-scale simulated fluidized-bed combustion facility. The experimental results from this study are presented in this report. Finally, the proposed work for the next quarter is described.

Wei-Ping Pan; Andy Wu; John T. Riley

2005-07-30

435

ESTABLISHMENT OF AN ENVIRONMENTAL CONTROL TECHNOLOGY LABORATORY WITH A CIRCULATING FLUIDIZED-BED COMBUSTION SYSTEM  

SciTech Connect

This report is to present the progress made on the project ''Establishment of an Environmental Control Technology Laboratory (ECTL) with a Circulating Fluidized-Bed Combustion (CFBC) System'' during the period January 1, 2005 through March 31, 2005. The following tasks have been completed. First, the renovation of the new Combustion Laboratory is nearly complete, and the construction of the Circulating Fluidized-Bed (CFB) Combustor Building is in the final stages. Second, the fabrication and manufacture of the CFBC Facility is being discussed with a potential contractor. Discussions with potential contactor regarding the availability of materials and current machining capabilities have resulted in the modification of the original designs. The selection of the fabrication contractor for the CFBC Facility is expected during the next quarter. Third, co-firing experiments conducted with coal and chicken waste have been initiated in the laboratory-scale simulated fluidized-bed facility. The experimental results from this study are presented in this report. Finally, the proposed work for the next quarter is described in this report.

Wei-Ping Pan; Andy Wu; John T. Riley

2005-04-30

436

Abatement of N{sub 2}O emissions from circulating fluidized bed combustion through afterburning  

SciTech Connect

A method for the abatement of N{sub 2}O emission from fluidized bed combustion has been investigated. The method consists of burning a secondary fuel after the normal circulating fluidized bed combustor. Liquefied petroleum gas (LPG), fuel oil, pulverized coal, and wood, as well as sawdust, were used as the secondary fuel. Experiments showed that the N{sub 2}O emission can be reduced by 90% or more by this technique. The resulting N{sub 2}O emission was principally a function of the gas temperature achieved in the afterburner and independent of afterburning fuel, but the amount of air in the combustion gases from the primary combustion also influences the results. No negative effects on sulfur capture or on NO or CO emissions were recorded. In the experiments, the primary cyclone of the fluidized bed boiler was used for afterburning. If afterburning is implemented in a plant optimized for this purpose, an amount of secondary fuel corresponding to 10% of the total energy input should remove practically all N{sub 2}O. During the present experiments the secondary fuel consumption was greater than 10% of the total energy input due to various losses.

Gustavsson, L. [Swedish National Testing and Research Inst., Boraas (Sweden); Leckner, B. [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Energy Conversion

1995-04-01

437

Parametric performance studies on fluidized-bed heat exchangers. Quarterly technical progress report, 1 October-31 December 1981  

SciTech Connect

Analyses and experiments will be performed to investigate the performance of single- and multi-stage shallow fluidized beds for possible application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. This work is an extension of work done previously under Contracts EC-77-C-03-1433 and DE-AC03-79-ET11348. In the present contract (DE-AC22-81-PC04280), tests will be conducted to (1) investigate the effects of fouling due to liquid condensate in the gas stream on fluidized bed heat exchanger performance, (2) investigate the performance of fluidized beds which are staged using baffle plates, and (3) investigate the effects of different heat exchanger surface geometries. Work has progressed in selecting the conditions for that portion of the program involving fouling by a liquid condensate; and in modifying the Fluidized Bed Heat Exchanger Facility for the fouling experiments. Preliminary tests were conducted with water vapor injection. Water vapor and glycerol vapor have been chosen as the condensates. The results may be summarized as follows: (1) heat exchanger performance is seriously degraded by condensation when the dew point temperature exceeds the heat exchanger wall temperature; and (2) the performance decrease occurs as a result of particle adherence to the heat exchanger surface and not as a result of particle agglomeration. Further tests to substantiate this result and to obtain additional performance results are planned for the next quarter.

Stoeffler, R.C.

1982-01-01

438

Parametric performance studies on fluidized-bed heat exchangers. Quarterly technical progress report, 1 January-31 March 1982  

SciTech Connect

Analyses and experiments will be performed in this program to investigate the performance of single- and multi-stage shallow fluidized beds for possible application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. Tests will be conducted to (1) investigate the effects of fouling due to liquid condensate in the gas stream on fluidized bed heat exchanger performance, (2) investigate the performance of fluidized beds which are staged using baffle plates, and (3) investigate the effects of different heat exchanger surface geometries. During this quarter, work progressed in fouling experiments of the Fluidized Bed Heat Exchanger using water injection into the inlet plenum. Results may be summarized as follows: Heat exchanger performance is seriously degraded when the dew point temperature exceeds the heat exchanger surface temperature. The performance decrease occurs as a result of particle adherence to the heat exchanger surface and not as a result of particle agglomeration. Neither an increase nor a decrease in bed fluidization changes the manner in which condensation affects heat exchanger performance. Changing the bed material from spherical glass beads to irregularly shaped Al/sub 2/O/sub 3/ particles did not alter the manner in which condensation affects heat exchanger performance. Original heat exchanger performance can be re-attained after condensation has occurred by operating the bed in the dry state for 2 to 3 hours to allow the scrubbing action of the bed to abrade adhering bed particles.

Stoeffler, R.C.

1982-04-01

439

Multistage fluidized bed reactor performance characterization for adsorption of carbon dioxide  

SciTech Connect

Carbon dioxide and its different compounds are generated as primary greenhouse gases from the flue gases of coal-fired thermal power plants, boilers, and other stationary combustion processes. This greenhouse gas causes global warming after being emitted to the environment. To deal with this problem, a new dry scrubbing process was tested in this study. A three-stage countercurrent fluidized bed adsorber was developed, designed, and fabricated. It was used as a removal apparatus and operated in a continuous regime for the two-phase system. The height of each stage was 0.30 m, and the inner diameter was 0.10 m. The paper presents the removal of CO{sub 2} from gas mixtures by chemical sorption on porous granular calcium oxide particles in the reactor at ambient temperature. The advantages of a multistage fluidized bed reactor for high mass transfer and high gas-solid contact can enhance the removal of the gas when using a dry method. The effects of the operating parameters such as sorbent, superficial gas velocity, and the Weir height on CO{sub 2} removal efficiency in the multistage fluidized bed were investigated. The results indicate that the removal efficiency of the carbon dioxide was around 71% at a high solid flow rate corresponding to lower gas velocity at room temperature. In comparison with wet scrubbers, this dry process appears to have lower cost, less complicated configuration, and simpler disposal of used sorbent. The results in this study assume importance from the perspective of use of a multistage fluidized bed adsorber for control of gaseous pollutants at high temperature.

Roy, S.; Mohanty, C.R.; Meikap, B.C. [Indian Institute of Technology, Kharagpur (India). Dept. of Chemical Engineering

2009-12-15

440

DEVELOPMENT OF PRESSURIZED CIRCULATING FLUIDIZED BED PARTIAL GASIFICATION MODULE (PGM)  

SciTech Connect

Foster Wheeler Development Corporation is working under DOE contract No. DE-FC26-00NT40972 to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% while producing near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal-derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The unique aspect of the process is that it utilizes a pressurized circulating fluidized bed partial gasifier and does not attempt to consume the coal in a single step. To convert all the coal to syngas in a single step requires extremely high temperatures ({approx}2500 to 2800F) that melt and vaporize the coal and essentially drive all coal ash contaminants into the syngas. Since these contaminants can be corrosive to power generating equipment, the syngas must be cooled to near room temperature to enable a series of chemical processes to clean the syngas. Foster Wheeler's process operates at much lower temperatures that control/minimize the release of contaminants; this eliminates/minimizes the need for the expensive, complicated syngas heat exchangers and chemical cleanup systems typical of high temperature gasification. By performing the gasification in a circulating bed, a significant amount of syngas can still be produced despite the reduced temperature and the circulating bed allows easy scale up to large size plants. Rather than air, it can also operate with oxygen to facilitate sequestration of stack gas carbon dioxide gases for a 100% reduction in greenhouse gas emissions. The amount of syngas and char produced by the PGM can be tailored to fit the production objectives of the overall plant, i.e., power generation, clean liquid fuel production, chemicals production, etc. Hence, PGM is a robust building block that offers all the advantages of coal gasification but in a more user friendly form; it is also fuel flexible in that it can use alternative fuels such as biomass, sewerage sludge, etc. The PGM consists of a pressurized circulating fluidized bed (PCFB) reactor together with a recycle cyclone and a particulate removing barrier filter. Coal, air, steam, and possibly sand are fed to the bottom of the PCFB reactor and establish a relatively dense bed of coal/char in the bottom section. As these constituents react, a hot syngas is produced which conveys the solids residue vertically up through the reactor and into the recycle cyclone. Solids elutriated from the dense bed and contained in the syngas are collected in the cyclone and drain via a dipleg back to the dense bed at the bottom of the PCFB reactor. This recycle loop of hot solids acts as a thermal flywheel and promotes efficient solid-gas chemical reaction.

Unknown

2001-07-10

441

Monitoring fluidized bed drying of pharmaceutical granules.  

PubMed

Placebo granules consisting of lactose monohydrate, corn starch, and polyvinylpyrrolidone were prepared using de-ionized water in a high-shear mixer and dried in a conical fluidized bed dryer at various superficial gas velocities. Acoustic, vibration, and pressure data obtained over the course of drying was analyzed using various statistical, frequency, fractal, and chaos techniques. Traditional monitoring methods were also used for reference. Analysis of the vibration data showed that the acceleration levels decreased during drying and reached a plateau once the granules had reached a final moisture content of 1–2 wt.%; this plateau did not differ significantly between superficial gas velocities, indicating a potential criterion to support drying endpoint identification. Acoustic emissions could not reliably identify the drying endpoint. However, high kurtosis values of acoustic emissions measured in the filtered air exhaust corresponded to high entrainment rates. This could be used for process control to adjust the fluidization gas velocity to allow drying to continue rapidly while minimizing entrainment and possible product losses. PMID:21061102

Briens, Lauren; Bojarra, Megan

2010-12-01

442

FLUIDIZED BED STEAM REFORMING ENABLING ORGANIC HIGH LEVEL WASTE DISPOSAL  

SciTech Connect

Waste streams planned for generation by the Global Nuclear Energy Partnership (GNEP) and existing radioactive High Level Waste (HLW) streams containing organic compounds such as the Tank 48H waste stream at Savannah River Site have completed simulant and radioactive testing, respectfully, by Savannah River National Laboratory (SRNL). GNEP waste streams will include up to 53 wt% organic compounds and nitrates up to 56 wt%. Decomposition of high nitrate streams requires reducing conditions, e.g. provided by organic additives such as sugar or coal, to reduce NOX in the off-gas to N2 to meet Clean Air Act (CAA) standards during processing. Thus, organics will be present during the waste form stabilization process regardless of the GNEP processes utilized and exists in some of the high level radioactive waste tanks at Savannah River Site and Hanford Tank Farms, e.g. organics in the feed or organics used for nitrate destruction. Waste streams containing high organic concentrations cannot be stabilized with the existing HLW Best Developed Available Technology (BDAT) which is HLW vitrification (HLVIT) unless the organics are removed by pretreatment. The alternative waste stabilization pretreatment process of Fluidized Bed Steam Reforming (FBSR) operates at moderate temperatures (650-750 C) compared to vitrification (1150-1300 C). The FBSR process has been demonstrated on GNEP simulated waste and radioactive waste containing high organics from Tank 48H to convert organics to CAA compliant gases, create no secondary liquid waste streams and create a stable mineral waste form.

Williams, M

2008-05-09

443

Parametric performance studies on fluidized-bed heat exchangers. Quarterly technical progress report, 1 October31 December 1981  

Microsoft Academic Search

Analyses and experiments will be performed to investigate the performance of single- and multi-stage shallow fluidized beds for possible application to the recovery of heat from sources such as waste heat, and coal combustion or coal gasification. This work is an extension of work done previously under Contracts EC-77-C-03-1433 and DE-AC03-79-ET11348. In the present contract (DE-AC22-81-PC04280), tests will be conducted

Stoeffler

1982-01-01

444

Staged combustion of rice straw in a fluidized bed  

SciTech Connect

Staged combustion of rice straw has been investigated using an atmospheric bubbling fluidized bed combustor. The combustor has a 300 mm ID and a 3300 mm height. Secondary air was introduced in the freeboard at 1500 mm above the primary air distributor. Rice straw was fed as cylindrical pellets of a 12 mm diameter and 10-15 mm lengths. The obtained results indicate that staged combustion appears an effective technique to reduce NO{sub x} emissions, in particular, at higher operating temperatures. Typically, at 850 C bed temperature, NO{sub x} concentration is reduced by about 50% when 30% of fed air is introduced as secondary air. Staged operation has a slight, non-monotonic effect on SO{sub 2} emission. Combustion efficiency improves with increasing secondary air ratio reaching a maximum value that is mainly attributed to a reduction in fixed carbon loss. With further increase in secondary air ratio, combustion efficiency, however, decreases again since entrained fixed carbon and exhausted carbon monoxide tend to increase. The range of secondary air ratio, over which combustion efficiency improves, expands at higher operating temperatures. (author)

Okasha, F. [Department of Mechanical Engineering, Mansoura University (Egypt)

2007-10-15

445

Biomass co-firing in a pressurized fluidized bed combustion (PFBC) combined cycle power plant: A techno-environmental assessment based on computational simulations  

Microsoft Academic Search

The co-utilization of coal with biomass and biomass waste in a pressurized fluidized bed combustion (PFBC) system is a promising power generation option for addressing various areas of concern relating to the anthropogenic sources of harmful emissions, the global reliance on fossil fuel and the overall energy supply issues. In this study, coal with a wide range of biomass and

Y. Huang; D. McIlveen-Wright; S. Rezvani; Y. D. Wang; N. Hewitt; B. C. Williams

2006-01-01

446

Fluidized-bed energy technology for biomass conversion  

SciTech Connect

Fluidized-bed technology offers several unique features for use in small-scale biomass energy conversion. Results are reported in the use of a 61-cm fluidized-bed reactor for combustion and on the use of 61-, 30-, and 5-cm reactors for gasification. combustion trials using agricultural biomass feeds have identified several problem areas. Slagging and fouling can occur at bed temperatures as low as 760/sup 0/C. Moreover, metal coupons placed in the hot exhaust gas stream experienced high rates of corrosion and erosion. Gasification experiments have confirmed that a fluidized bed will accept a wide range of biomass feeds (rice hulls, corncobs, sorghum stalks, cottom gin trash) and convert them into a low-Btu combustible gas. Slagging and fouling were not as severe when operating the fluidized bed in the gasification mode. Gas cleanup requirements as well as technical needs in evaluating corrosion of reactor construction materials are identified. Coupling of the 61-cm reactor to a steam boiler is described. Finally, the nature of fluidized-bed technology suggests potentials for biomass pyrolysis, and such use is examined. 2 figures, 5 tables.

Soltes, E.J.; Lepori, W.A.; Pollock, T.C.

1982-01-01

447

FLUIDIZED BED STEAM REFORMER MONOLITH FORMATION  

SciTech Connect

Fluidized Bed Steam Reforming (FBSR) is being considered as an alternative technology for the immobilization of a wide variety of aqueous high sodium containing radioactive wastes at various DOE facilities in the United States. The addition of clay, charcoal, and a catalyst as co-reactants converts aqueous Low Activity Wastes (LAW) to a granular or ''mineralized'' waste form while converting organic components to CO{sub 2} and steam, and nitrate/nitrite components, if any, to N{sub 2}. The waste form produced is a multiphase mineral assemblage of Na-Al-Si (NAS) feldspathoid minerals with cage-like structures that atomically bond radionuclides like Tc-99 and anions such as SO{sub 4}, I, F, and Cl. The granular product has been shown to be as durable as LAW glass. Shallow land burial requires that the mineralized waste form be able to sustain the weight of soil overburden and potential intrusion by future generations. The strength requirement necessitates binding the granular product into a monolith. FBSR mineral products were formulated into a variety of monoliths including various cements, Ceramicrete, and hydroceramics. All but one of the nine monoliths tested met the <2g/m{sup 2} durability specification for Na and Re (simulant for Tc-99) when tested using the Product Consistency Test (PCT; ASTM C1285). Of the nine monoliths tested the cements produced with 80-87 wt% FBSR product, the Ceramicrete, and the hydroceramic produced with 83.3 wt% FBSR product, met the compressive strength and durability requirements for an LAW waste form.

Jantzen, C

2006-12-22

448

Waste tire fluidized bed combustion boiler project  

SciTech Connect

The objective was to commercially demonstrate a fluidized bed combustion (F.B.C.) system that could convert waste tires into steam energy at a convenience level approximately that of oil or gas-fired boilers. In order to burn tires in a F.B.C. unit, the tires must first be chopped into a maximum size of four inches by four inches. This was readily accomplished in a tire chopper modified for multi-pass operation. The chopper could be mounted on a truck or trailer and use gasoline or other fuels making it suitable for mobile operation. A test program was conducted to determine performance and design criteria, which were used to specify a commercial scale steam generation demonstration unit. It was found that 100% of the heat of combustion available in tires can be released in a F.B.C. unit. Tires must be combusted at 775 +- 25/sup 0/C to provide for fiberglass removal. Unburned carbon black along with fiberglass, zinc oxide, bed fines and scrap wire would have to be landfilled. Sulfur dioxide and nitrogen oxide emissions would be below the limits imposed by the Michigan Department of Natural Resources. Particulate emissions downstream of the cyclone would have to be limited by some system such as a bag house. A site was prepared for the pilot model site at National-Standard Lake Street Plant Building No. 6 in Niles, Michigan. The tire chopper and most of the auxiliary equipment was installed. Before contracts were awarded to construct the F.B.C. unit, a revised financial analysis showed that the investment required for the F.B.C. unit made the entire system uneconomical. Although the operating costs of the waste tire system was considerably less than that of gas or oil fired boilers, the large initial investment for the system made the payback period 12 to 18 years.

Not Available

1984-03-01

449

DEVELOPMENT OF PRESSURIZED CIRCULATING FLUIDIZED BED PARTIAL GASIFICATION MODULE (PGM)  

SciTech Connect

Foster Wheeler Development Corporation is working under DOE contract No. DE-FC26-00NT40972 to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% while producing near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal-derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The unique aspect of the process is that it utilizes a pressurized circulating fluidized bed partial gasifier and does not attempt to consume the coal in a single step. To convert all the coal to syngas in a single step requires extremely high temperatures ({approx}2500 to 2800 F) that melt and vaporize the coal and essentially drive all coal ash contaminants into the syngas. Since these contaminants can be corrosive to power generating equipment, the syngas must be cooled to near room temperature to enable a series of chemical processes to clean the syngas. Foster Wheeler's process operates at much lower temperatures that control/minimize the release of contaminants; this eliminates/minimizes the need for the expensive, complicated syngas heat exchangers and chemical cleanup systems typical of high temperature gasification. By performing the gasification in a circulating bed, a significant amount of syngas can still be produced despite the reduced temperature and the circulating bed allows easy scale up to large size plants. Rather than air, it can also operate with oxygen to facilitate sequestration of stack gas carbon dioxide gases for a 100% reduction in greenhouse gas emissions.

Unknown

2002-03-29

450

Methods of forming a fluidized bed of circulating particles  

SciTech Connect

There is disclosed an apparatus for forming a fluidized bed of circulating particles. In an embodiment, the apparatus includes a bottom portion having a sidewall, the sidewall defining a curvilinear profile, and the bottom portion configured to contain a bed of particles; and a gas inlet configured to produce a column of gas to carry entrained particles therein. There is disclosed a method of forming a fluidized bed of circulating particles. In an embodiment, the method includes positioning particles within a bottom portion having a sidewall, the sidewall defining a curvilinear profile; producing a column of gas directed upwardly through a gas inlet; carrying entrained particles in the column of gas to produce a fountain of particles over the fluidized bed of circulating particles and subside in the particle bed until being directed inwardly into the column of gas within the curvilinear profile.

Marshall, Douglas W. (Blackfoot, ID)

2011-05-24

451

Fluidized bed reactor system and method having a heat exchanger  

SciTech Connect

A fluidized bed reactor system is described comprising a reactor, means for supporting a fluidized bed of combustible particulate material in said reactor, heat exchange means disposed adjacent said reactor, separating means for receiving a mixture of flue gases and entrained particulate material from said fluidized bed and separating said particulate material from said flue gases, means for passing said separated particulate material to said heat exchange means, means for passing air through said separated particulate material in said heat exchange means to fluidize said separated material, means disposed in said heat exchange means for passing a coolant in a heat exchange relation to said separated material to transfer heat from said separated material to said coolant, and means for supplying additional heat to said separated material in said heat exchange means to control the temperature of said coolant.

Garcia-Mallol, J.A.

1993-08-31

452

Concept for a super-clean super-efficient pressurized fluidized-bed combustion system  

SciTech Connect

A paper study for a highly efficient, environmentally benign, coal-fired electric power generation system, is presented. This system falls in the category of pressurized fluidized-bed combustion (PFBC) systems which has been dubbed super-clean super-efficient PFBC`s. The system presented starts with the second-generation PFBC concept and adds on advanced gas turbine, a solid oxide fuel cell, a supercritical steam cycle, a second low-temperature rankine cycle which pulls energy from the steam condenser, and inlet air cooling. The thermodynamic efficiency of the system is calculated to be 61.8 percent based on higher heating value (HHV).

Mollott, D.J.; Reed, M.

1994-12-31

453

Conversion of solid carbonaceous fuels in a fluidized bed fuel cell  

SciTech Connect

A fluidized bed direct carbon fuel cell was employed to achieve direct conversion of solid fuels into electricity. Power was generated from pulverized Lower Kittanning (bituminous) coal, synthetic carbon, and biomass in a single process step. Current-voltage characteristics exhibited typical fuel cell behavior. Fluidization in flowing CO{sub 2} overcomes the difficulty of attaining solid fuel-to-anode contact and generates CO in situ via the Boudouard reaction. A mechanistic reaction pathway is proposed for anodic oxidation of the solid fuel. Conversion was verified by gas analysis of oxidation products in the flue stream and by oxygen mass balance.

Lee, A.C.; Li, S.; Mitchell, R.E.; Guer, T.M. [Stanford University, Stanford, CA (United States). Dept. of Mechanical Engineering

2008-07-01

454

Computational fluid dynamic modeling of fluidized-bed polymerization reactors  

SciTech Connect

Polyethylene is one of the most widely used plastics, and over 60 million tons are produced worldwide every year. Polyethylene is obtained by the catalytic polymerization of ethylene in gas and liquid phase reactors. The gas phase processes are more advantageous, and use fluidized-bed reactors for production of polyethylene. Since they operate so close to the melting point of the polymer, agglomeration is an operational concern in all slurry and gas polymerization processes. Electrostatics and hot spot formation are the main factors that contribute to agglomeration in gas-phase processes. Electrostatic charges in gas phase polymerization fluidized bed reactors are known to influence the bed hydrodynamics, particle elutriation, bubble size, bubble shape etc. Accumulation of electrostatic charges in the fluidized-bed can lead to operational issues. In this work a first-principles electrostatic model is developed and coupled with a multi-fluid computational fluid dynamic (CFD) model to understand the effect of electrostatics on the dynamics of a fluidized-bed. The multi-fluid CFD model for gas-particle flow is based on the kinetic theory of granular flows closures. The electrostatic model is developed based on a fixed, size-dependent charge for each type of particle (catalyst, polymer, polymer fines) phase. The combined CFD model is first verified using simple test cases, validated with experiments and applied to a pilot-scale polymerization fluidized-bed reactor. The CFD model reproduced qualitative trends in particle segregation and entrainment due to electrostatic charges observed in experiments. For the scale up of fluidized bed reactor, filtered models are developed and implemented on pilot scale reactor.

Rokkam, Ram [Ames Laboratory

2012-11-02

455

Two-stage dual fluidized bed gasification: Its conception and application to biomass  

Microsoft Academic Search

The quoted two-stage dual fluidized bed gasification (T-DFBG) devises the use of a two-stage fluidized bed (TFB) to replace the single-stage bubbling fluidized bed gasifier involved in the normally encountered dual fluidized bed gasification (N-DFBG) systems. By feeding fuel into the lower stage of the TFB, this lower stage functions as a fuel gasifier similar to that in the N-DFBG

Guangwen Xu; Takahiro Murakami; Toshiyuki Suda; Yoshiaki Matsuzaw; Hidehisa Tani

2009-01-01

456

Fluidized-bed energy technology for biomass conversion  

SciTech Connect

Fluidized bed technology was experimentally evaluated for the combustion and gasification of cotton gin waste. The isothermal bed temperatures in the reactors could be maintained below the ash fusion point of the waste. Raw stripper harvested cotton gin trash could be metered directly into the fluidized-bed reactors indicating that little feed preparation is required. H and CO were the primary products of gasification, and approximately 3200-400 Btu of gas were produced per lb of cotton gin waste. These techniques offer the potential of providing small-scale energy conversion systems for use on farms.

LePori, W.A.; Anthony, R.G.; Lalk, T.R.; Craig, J.; Groves, J.

1980-01-01

457

Pressurized fluidized-bed combustion technology exchange workshop  

SciTech Connect

The pressurized fluidized-bed combustion technology exchange workshop was held June 5 and 6, 1979, at The Meadowlands Hilton Hotel, Secaucus, New Jersey. Eleven papers have been entered individually into EDB and ERA. The papers include reviews of the US DOE and EPRI programs in this area and papers by Swedish, West German, British and American organizations. The British papers concern the joint program of the USA, UK and FRG at Leatherhead. The key factor in several papers is the use of fluidized bed combustors, gas turbines, and steam turbines in combined-cycle power plants. One paper examines several combined-cycle alternatives. (LTN)

,

1980-04-01

458

Calculational methods for performance of heat exchangers enhanced with fluidized bed  

Microsoft Academic Search

The characteristics of fluidized beds are such that the analytical procedures for calculating the performance of conventional heat exchangers are not applicable to heat exchangers using fluidized bed heat transfer enhancement. Analytical procedures applicable to two different design approaches to heat exchangers utilizing fluidized bed heat transfer enhancement are developed, and the results are presented in graphical form.

M Suo

1976-01-01

459

Drying of a Dilute Suspension in a Revolving Flow Fluidized Bed of Inert Particles  

Microsoft Academic Search

Revolving air flow was generated by oblique holes on air distribution board in a fluidized bed dryer. Such a revolving air flow shows a large scale velocity fluctuation in radial as well as tangential directions. This turbulent flow of air can fluidize the inert particles with superior performance than vibrated fluidized bed. The revolving fluidized bed is simpler in fabrication

Lijuan Zhao; Yongkang Pan; Jianguo Li; Guohua Chen; Arun S. Mujumdar

2004-01-01

460

Design of advanced fossil-fuel systems (DAFFS). A study of three developing technologies for coal-fired, base-load electric power generation. Air-cooled pressurized fluidized-bed power plant  

SciTech Connect

The objectives of this report are to present the facility description, plant layouts and additional information which define the conceptual engineering design, and to provide performance and cost estimates for the air-cooled pressurized fluidized bed (PFB) power plant. Following the introductory comments, the results of the study of the air-cooled PFB power plant are summarized in Section 2. In Section 3, a description of plant systems and facilities is provided. Section 4 includes pertinent performance information and assessments of availability, natural resource requirements and environmental impact. Estimates of capital costs, operating and maintenance (O and M) costs and cost of electricity are presented in Section 5. Bechtel comments regarding the plant configuration and performance are provided in Section 6. The design and cost estimate reports which were prepared by Westinghouse for items within their scope of responsibility are included as Appendices A and B, respectively. Appendix C is the power plant equipment list for systems within the BGI scope. The design and cost estimate classifications chart referenced in Section 5 is included as Appendix D. 7 references, 19 figures, 13 tables.

Not Available

1983-06-01

461

Design of advanced fossil-fuel systems (DAFFS). A study of three developing technologies for coal-fired, base-load electric power generation. Steam-cooled pressurized fluidized-bed power plant  

SciTech Connect

The objectives of this report are to present the facility description, plant layouts, and additional information which define the conceptal engineering design, and to provide performance and cost estimates for the steam-cooled pressurized fluidized-bed (PFB) power plant. Following the introductory comments, the results of the study of the steam-cooled PFB power plant are summarized in Section 2. In Section 3, a description of plant systems and facilities is provided. Section 4 includes pertinent performance informtion and assessments of availability, natural resource requirements and environmetal impact. Estimates of capital costs, operating and maintenance costs and cost of electricity are presented in Section 5. Bechtel comments regarding the plant configuration and performance are provided in Section 6. The design and cost estimate reports which were prepared by Westinghouse for items within their scope of responsibility are included as Appenices A and B, respectively. Appendix C is the power plant equipment list for systems within the BGI scope. The design and cost estimate classifications chart referenced in Section 5 is included as Appendix D. 6 references, 20 figures, 13 tables

Not Available

1983-06-01

462

Pressurized Fluidized Bed Combustion Second-Generation System Research and Development  

SciTech Connect

Research is being conducted under United States Department of Energy (DOE) Contract DE-AC21-86MC21023 to develop a new type of coal-fired plant for electric power generation. This new type of plant--called a Second-Generation or Advanced Pressurized Circulating Fluidized Bed Combustion (APCFB) plant--offers the promise of efficiencies greater than 45% (HHV), with both emissions and a cost of electricity that are significantly lower than conventional pulverized-coal-fired plants with scrubbers. The APCFB plant incorporates the partial gasification of coal in a carbonizer, the combustion of carbonizer char in a pressurized circulating fluidized bed boiler (PCFB), and the combustion of carbonizer syngas in a topping combustor to achieve gas turbine inlet temperatures of 2300 F and higher. A conceptual design was previously prepared for this new type of plant and an economic analysis presented, all based on the use of a Siemens Westinghouse W501F gas turbine with projected carbonizer, PCFB, and topping combustor performance data. Having tested these components at the pilot plant stage, the referenced conceptual design is being updated to reflect more accurate performance predictions together with the use of the more advanced Siemens Westinghouse W501G gas turbine and a conventional 2400 psig/1050 F/1050 F/2-1/2 in. steam turbine. This report describes the updated plant which is projected to have an HHV efficiency of 48% and identifies work completed for the October 2001 through September 2002 time period.

A. Robertson; D. Horazak; R. Newby; H. Goldstein

2002-11-01

463

Meat and bone meal as secondary fuel in fluidized bed combustion  

SciTech Connect

Meat and Bone Meal (MBM) was co-fired in a laboratory scale fluidized bed combustion (FBC) apparatus with two coals. Several fuel blends were combusted under different conditions to study how primary fuel substitution by MBM affects flue gas emissions as well as fluidized bed (FB) agglomeration tendency. MBM, being a highly volatile fuel, caused significant increase of CO emissions and secondary air should be used in industrial scale applications to conform to regulations. The high N-content of MBM is moderately reflected on the increase of nitrogen oxides emissions which are reduced by MBM derived volatiles. The MBM ash, mainly containing bone material rich in Ca, did not create any noteworthy desulphurization effect. The observed slight decrease in SO{sub 2} emissions is predominantly attributed to the lower sulphur content in the coal/MBM fuel mixtures. The SEM/EDS analysis of bed material samples from the coal/MBM tests revealed the formation of agglomerates of bed material debris and ash with sizes that do not greatly exceed the original bed inventory and thus not problematic. 37 refs., 9 figs., 3 tabs.

L. Fryda; K. Panopoulos; P. Vourliotis; E. Kakaras; E. Pavlidou [National Technical University of Athens, Athens (Greece). Laboratory of Steam Boilers and Thermal Plants, School of Mechanical Engineering

2007-07-01

464

Establishment of an Environmental Control Technology Laboratory with a Circulating Fluidized-Bed Combustion System  

SciTech Connect

This report is to present the progress made on the project entitled ''Establishment of an Environmental Control Technology Laboratory (ECTL) with a Circulating Fluidized-Bed Combustion (CFBC) System'' during the period January 1, 2007 through March 31, 2007. The effort in this quarter has concentrated on installing the CFBC Facility and for conducting cold fluidization operations tests in the CFBC facility. The assembly of the ash recirculation pipe duct from the cyclones back to the bed area of the combustor, including the upper and lower loop seals was completed. The electric bed pre-heater was installed to heat the fluidizing air as it enters the wind box. The induced draft fan along with its machine base and power supply was received and installed. The flue gas duct from secondary cyclone outlet to induced draft fan inlet was received and installed, as well as the induced fan flue gas discharge duct. Pressure testing from the forced draft fan to the outlet of the induced fan was completed. In related research a pilot-scale halogen addition test was conducted in the empty slipstream reactor (without (Selective Catalytic Reduction) SCR catalyst loading) and the SCR slipstream reactor with two commercial SCR catalysts. The greatest benefits of conducting slipstream tests can be flexible control and isolation of specific factors. This facility is currently used in full-scale utility and will be combined into 0.6MW CFBC in the future. This work attempts to first investigate performance of the SCR catalyst in the flue gas atmosphere when burning Powder River Basin (PRB), including the impact of PRB coal flue gas composition on the reduction of nitrogen oxides (NOx) and the oxidation of elemental mercury (Hg(0)) under SCR conditions. Secondly, the impacts of hydrogen halogens (Hydrogen fluoride (HF), Hydrogen chloride (HCl), Hydrogen Bromide (HBr) and Hydrogen Iodine (HI)) on Hg(0) oxidation and their mechanisms can be explored.

Wei-Ping Pan; Yan Cao; John Smith