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Sample records for cement production process

  1. Characteristics of mercury cycling in the cement production process.

    PubMed

    Wang, Fengyang; Wang, Shuxiao; Zhang, Lei; Yang, Hai; Wu, Qingru; Hao, Jiming

    2016-01-25

    The mercury cycling caused by dust shuttling significantly increases the atmospheric emissions from cement production. A comprehensive understanding of this mercury cycling can promote the development of mercury emission control technologies. In this study, the characteristics of mercury cycling in the cement production process were first investigated. Furthermore, the mercury enrichment and effects of dust treatment were evaluated based on the field tests conducted in two Chinese cement plants. The mercury cycling between the kiln system and the raw mill system was the most important aspect and contributed 57-73% to the total amount of mercury emitted from the kiln system. Mercury emitted from the kiln system with flue gas was enriched as high as 3.4-8.8 times in the two tested plants compared to the amount of mercury in the raw materials and coal due to mercury cycling. The mercury enrichment can be significantly affected by the proportion of mercury cycled back to the kiln system. The effects of dust treatment were evaluated, and dust treatment can efficiently reduce approximately 31-70% of atmospheric mercury emissions in the two plants. The reduction proportion approximately linearly decreased with the proportion of mercury removed from the collected dust. PMID:26448491

  2. Sulfur cement production using by products of the perchloroethylene coal cleaning process and the FC4-1 cleaned soil

    SciTech Connect

    Bassam Masri, K.L.; Fullerton, S.L.

    1995-12-31

    An introductory set of experiments to show the feasibility of making sulfur cement were carried out at the University of Akron according to Parrett and Currett`s patent which requires the use of sulfur, a filler, a plasticizer, and a vulcanization accelerator. Small blocks of cement were made using byproducts of the perchloroethylene coal cleaning process. Extracted elemental and organic sulfur, ash and mineral matters from the float sink portion of the PCE process, and FC4-1 cleaned soil were used as substitutes for sulfur and filler needed for the production of sulfur cement. Leaching tests in different solutions and under different conditions were conducted on the sulfur blocks. Other tests such as strength, durability, resistance to high or low temperatures will be conducted in the future. Sulfur cement can be used as a sealing agent at a joint, roofing purposes, forming ornamental figures, and coating of exposed surfaces of iron or steel. When mixed with an aggregate, sulfur concrete is formed. This concrete can be used for structural members, curbings, guthers, slabs, and can be precast or cast at the job site. An advantage of sulfur cement over Portland cement is that it reaches its design strength in two to three hours after processing and it can be remelted and recast.

  3. Process for cementing a well

    SciTech Connect

    Cowan, K.M.; Hale, A.H.

    1991-06-04

    This paper describes a process for cementing a casing in a borehole of a well. It comprises: preparing an aqueous cement slurry containing a sufficient amount of a selected water soluble polyalcohol having from 2 to 18 carbon atoms and 2 to 13 hydroxyl groups, the concentration of polyalcohol in the water used to prepare and set the slurry being about 0.01 to about 5% by volume, the selection of the polyalcohol being restricted to a polyalcohol which functions to promote a more fluid-tight seal and better mechanical shear bond between the cement and surfaces contacting the cement; and injecting the cement slurry into the well between the casing and the borehole.

  4. Alternative Fuel for Portland Cement Processing

    SciTech Connect

    Anton K. Schindler; Steve R. Duke; Thomas E. Burch; Edward W. Davis; Ralph H. Zee; David I. Bransby; Carla Hopkins; Rutherford L. Thompson; Jingran Duan; Vignesh Venkatasubramanian; Stephen Giles.

    2012-06-30

    The production of cement involves a combination of numerous raw materials, strictly monitored system processes, and temperatures on the order of 1500 °C. Immense quantities of fuel are required for the production of cement. Traditionally, energy from fossil fuels was solely relied upon for the production of cement. The overarching project objective is to evaluate the use of alternative fuels to lessen the dependence on non-renewable resources to produce portland cement. The key objective of using alternative fuels is to continue to produce high-quality cement while decreasing the use of non-renewable fuels and minimizing the impact on the environment. Burn characteristics and thermodynamic parameters were evaluated with a laboratory burn simulator under conditions that mimic those in the preheater where the fuels are brought into a cement plant. A drop-tube furnace and visualization method were developed that show potential for evaluating time- and space-resolved temperature distributions for fuel solid particles and liquid droplets undergoing combustion in various combustion atmospheres. Downdraft gasification has been explored as a means to extract chemical energy from poultry litter while limiting the throughput of potentially deleterious components with regards to use in firing a cement kiln. Results have shown that the clinkering is temperature independent, at least within the controllable temperature range. Limestone also had only a slight effect on the fusion when used to coat the pellets. However, limestone addition did display some promise in regards to chlorine capture, as ash analyses showed chlorine concentrations of more than four times greater in the limestone infused ash as compared to raw poultry litter. A reliable and convenient sampling procedure was developed to estimate the combustion quality of broiler litter that is the best compromise between convenience and reliability by means of statistical analysis. Multi-day trial burns were conducted at a full-scale cement plant with alternative fuels to examine their compatibility with the cement production process. Construction and demolition waste, woodchips, and soybean seeds were used as alternative fuels at a full-scale cement production facility. These fuels were co-fired with coal and waste plastics. The alternative fuels used in this trial accounted for 5 to 16 % of the total energy consumed during these burns. The overall performance of the portland cement produced during the various trial burns performed for practical purposes very similar to the cement produced during the control burn. The cement plant was successful in implementing alternative fuels to produce a consistent, high-quality product that increased cement performance while reducing the environmental footprint of the plant. The utilization of construction and demolition waste, woodchips and soybean seeds proved to be viable replacements for traditional fuels. The future use of these fuels depends on local availability, associated costs, and compatibility with a facilityâ??s production process.

  5. Principles of technological design of wasteless chemical processes based on the use of wastes for production of alkaline slag cements and concretes

    SciTech Connect

    Glukhovskii, V.D.; Chernobaev, I.P.; Emel'yanov, B.M.; Semenyuk, A.P.

    1985-05-20

    The strength characteristics of alkaline slag-cement made with the use of waste from alkaline sealing of metals are presented. The cement was prepared from granulated blast-furnance slag with average component contents in the following ranges (mass %): SiO/sub 2/ 36.0-40.2, Al/sub 2/O/sub 3/ 4-18.2, FeO 0.1-3.7, MnO 0.4-5.2, CaO 33.1-48.8, MgO 2.2-9.8. With the use of wastes from the descaling process in alkali melts for production of alkaline slag cements it is possible to obtain highly effective cements of type 700-900, which is 2 to 3 times the value for portland cements. Therefore, the use of wastes from alkaline descaling for production of alkaline slag cements is of great economic and conservational significance. It is possible to devise a wasteless process of scale removal from metals; this is an important advantage of the alkaline scaling method over acid pickling.

  6. Identifying improvement potentials in cement production with life cycle assessment.

    PubMed

    Boesch, Michael Elias; Hellweg, Stefanie

    2010-12-01

    Cement production is an environmentally relevant process responsible for 5% of total anthropogenic carbon dioxide emissions and 7% of industrial fuel use. In this study, life cycle assessment is used to evaluate improvement potentials in the cement production process in Europe and the USA. With a current fuel substitution rate of 18% in Europe and 11% in the USA, both regions have a substantial potential to reduce greenhouse gas emissions and save virgin resources by further increasing the coprocessing of waste fuels. Upgrading production technology would be particularly effective in the USA where many kiln systems with very low energy efficiency are still in operation. Using best available technology and a thermal substitution rate of 50% for fuels, greenhouse gas emissions could be reduced by 9% for Europe and 18% for the USA per tonne of cement. Since clinker production is the dominant pollution producing step in cement production, the substitution of clinker with mineral components such as ground granulated blast furnace slag or fly ash is an efficient measure to reduce the environmental impact. Blended cements exhibit substantially lower environmental footprints than Portland cement, even if the substitutes feature lower grindability and require additional drying and large transport distances. The highest savings in CO(2) emissions and resource consumption are achieved with a combination of measures in clinker production and cement blending. PMID:21047057

  7. Process for cementing geothermal wells

    DOEpatents

    Eilers, Louis H. (Inola, OK)

    1985-01-01

    A pumpable slurry of coal-filled furfuryl alcohol, furfural, and/or a low molecular weight mono- or copolymer thereof containing, preferably, a catalytic amount of a soluble acid catalyst is used to cement a casing in a geothermal well.

  8. Characterization of cement minerals, cements and their reaction products at the atomic and nano scale 

    E-print Network

    Skibsted, Joergen; Hall, Christopher

    Recent advances and highlights in characterization methods are reviewed for cement minerals, cements and their reaction products. The emphasis is on X-ray and neutron diffraction, and on nuclear magnetic resonance methods, although X-ray absorption...

  9. Evaluation of a lime-mediated sewage sludge stabilisation process. Product characterisation and technological validation for its use in the cement industry.

    PubMed

    Rodríguez, N Husillos; Granados, R J; Blanco-Varela, M T; Cortina, J L; Martínez-Ramírez, S; Marsal, M; Guillem, M; Puig, J; Fos, C; Larrotcha, E; Flores, J

    2012-03-01

    This paper describes an industrial process for stabilising sewage sludge (SS) with lime and evaluates the viability of the stabilised product, denominated Neutral, as a raw material for the cement industry. Lime not only stabilised the sludge, raised the temperature of the mix to 80-100°C, furthering water evaporation, portlandite formation and the partial oxidation of the organic matter present in the sludge. Process mass and energy balances were determined. Neutral, a white powder consisting of portlandite (49.8%), calcite (16.6%), inorganic oxides (13.4%) and organic matter and moisture (20.2%), proved to be technologically apt for inclusion as a component in cement raw mixes. In this study, it was used instead of limestone in raw mixes clinkerised at 1400, 1450 and 1500°C. These raw meals exhibited greater reactivity at high temperatures than the limestone product and their calcination at 1500°C yielded clinker containing over 75% calcium silicates, the key phases in Portland clinker. Finally, the two types of raw meal (Neutral and limestone) were observed to exhibit similar mineralogy and crystal size and distribution. PMID:22119052

  10. Microscale investigation of arsenic distribution and species in cement product from cement kiln coprocessing wastes.

    PubMed

    Yang, Yufei; Xue, Jingchuan; Huang, Qifei

    2013-01-01

    To improve the understanding of the immobilization mechanism and the leaching risk of Arsenic (As) in the cement product from coprocessing wastes using cement kiln, distribution and species of As in cement product were determined by microscale investigation methods, including electron probe microanalysis (EPMA) and X-ray absorption spectroscopy. In this study, sodium arsenate crystals (Na3AsO412H2O) were mixed with cement production raw materials and calcined to produce cement clinker. Then, clinker was mixed water to prepare cement paste. EPMA results showed that As was generally distributed throughout the cement paste. As content in calcium silicate hydrates gel (C-S-H) was in low level, but higher than that in other cement mineral phases. This means that most of As is expected to form some compounds that disperse on the surfaces of cement mineral phases. Linear combination fitting (LCF) of the X-ray absorption near edge structure spectra revealed that As in the cement paste was predominantly As(V) and mainly existed as Mg3(AsO4)2, Ca3(AsO4)2, and Na2HAsO4. PMID:24223030

  11. Microscale Investigation of Arsenic Distribution and Species in Cement Product from Cement Kiln Coprocessing Wastes

    PubMed Central

    Yang, Yufei; Xue, Jingchuan; Huang, Qifei

    2013-01-01

    To improve the understanding of the immobilization mechanism and the leaching risk of Arsenic (As) in the cement product from coprocessing wastes using cement kiln, distribution and species of As in cement product were determined by microscale investigation methods, including electron probe microanalysis (EPMA) and X-ray absorption spectroscopy. In this study, sodium arsenate crystals (Na3AsO412H2O) were mixed with cement production raw materials and calcined to produce cement clinker. Then, clinker was mixed water to prepare cement paste. EPMA results showed that As was generally distributed throughout the cement paste. As content in calcium silicate hydrates gel (C-S-H) was in low level, but higher than that in other cement mineral phases. This means that most of As is expected to form some compounds that disperse on the surfaces of cement mineral phases. Linear combination fitting (LCF) of the X-ray absorption near edge structure spectra revealed that As in the cement paste was predominantly As(V) and mainly existed as Mg3(AsO4)2, Ca3(AsO4)2, and Na2HAsO4. PMID:24223030

  12. Hydration products and thermokinetic properties of cement-bentonite and cement-chalk mortars

    SciTech Connect

    Klyusov, A.A.

    1988-08-20

    Bentonite and chalk are the most popular auxiliary additives to portland cement for borehole cementation. The authors studied by physicochemical analysis methods (x-ray phase, derivatographic, and scanning and electron microscopy in combination with microdiffraction) the newly formed solid-phase composition of cement-bentonite and cement-chalk mortars (binder-additive ratio 9:1) prepared from portland cement for cold boreholes and 8% calcium chloride solution at a water-mixing ratio of 0.9. The mechanism of the influence of Ca-bentonite and chalk additives on the portland cement hydration rate was ascertained from the heat evolution rate curves. It was found that the phase compositions of the hydration products are represented in the studied systems by newly formed substances typical for portland cement. It has been noted that Ca-bentonite interacts with the calcium hydroxide of hydrated cement with the formation of hexagonal and cubic calcium hydroaluminates. Unlike Ca-bentonite, chalk does not react with portland cement at normal and reduced temperatures, does not block hydrated cement particles, which, in turn, ensures all other conditions remaining equal, a higher initial rate of hydration of cement-chalk mortar.

  13. A NONLINEAR LEARNING CONTROL APPROACH FOR A CEMENT MILLING PROCESS

    E-print Network

    Efe, Mehmet Önder

    A NONLINEAR LEARNING CONTROL APPROACH FOR A CEMENT MILLING PROCESS 1 OGUZ H. DAGCI, 2 M. ÖNDER EFE, control of a cement milling circuit is studied with time-varying set values, time-varying plant parameters popularity since the field of nonlinear control still does not offer systematized procedures. Cement mill

  14. Characterization of cement minerals, cements and their reaction products at the atomic and nano scale

    SciTech Connect

    Skibsted, Jorgen Hall, Christopher

    2008-02-15

    Recent advances and highlights in characterization methods are reviewed for cement minerals, cements and their reaction products. The emphasis is on X-ray and neutron diffraction, and on nuclear magnetic resonance methods, although X-ray absorption and Raman spectroscopies are discussed briefly.

  15. STUDY OF AMMONIA SOURCE AT A PORTLAND CEMENT PRODUCTION PLANT (JOURNAL VERSION)

    EPA Science Inventory

    A source and process sampling study was conducted at a dry process Portland Cement production plant. One aspect of the study focused on the source or point of NH3 within the production process. An extensive number of process solids from raw feeds to baghouse solids were collected...

  16. Sustainable cement production-present and future

    SciTech Connect

    Schneider, M.; Romer, M.; Tschudin, M.; Bolio, H.

    2011-07-15

    Cement will remain the key material to satisfy global housing and modern infrastructure needs. As a consequence, the cement industry worldwide is facing growing challenges in conserving material and energy resources, as well as reducing its CO{sub 2} emissions. According to the International Energy Agency, the main levers for cement producers are the increase in energy efficiency and the use of alternative materials, be it as fuel or raw materials. Accordingly, the use of alternative fuels has already increased significantly in recent years, but potential for further increases still exists. In cement, the reduction of the clinker factor remains a key priority: tremendous progress has already been made. Nevertheless, appropriate materials are limited in their regional availability. New materials might be able to play a role as cement constituents in the future. It remains to be seen to what extent they could substitute Portland cement clinker to a significant degree.

  17. Use of MRF residue as alternative fuel in cement production.

    PubMed

    Fyffe, John R; Breckel, Alex C; Townsend, Aaron K; Webber, Michael E

    2016-01-01

    Single-stream recycling has helped divert millions of metric tons of waste from landfills in the U.S., where recycling rates for municipal solid waste are currently over 30%. However, material recovery facilities (MRFs) that sort the municipal recycled streams do not recover 100% of the incoming material. Consequently, they landfill between 5% and 15% of total processed material as residue. This residue is primarily composed of high-energy-content non-recycled plastics and fiber. One possible end-of-life solution for these energy-dense materials is to process the residue into Solid Recovered Fuel (SRF) that can be used as an alternative energy resource capable of replacing or supplementing fuel resources such as coal, natural gas, petroleum coke, or biomass in many industrial and power production processes. This report addresses the energetic and environmental benefits and trade-offs of converting non-recycled post-consumer plastics and fiber derived from MRF residue streams into SRF for use in a cement kiln. An experimental test burn of 118Mg of SRF in the precalciner portion of the cement kiln was conducted. The SRF was a blend of 60% MRF residue and 40% post-industrial waste products producing an estimated 60% plastic and 40% fibrous material mixture. The SRF was fed into the kiln at 0.9Mg/h for 24h and then 1.8Mg/h for the following 48h. The emissions data recorded in the experimental test burn were used to perform the life-cycle analysis portion of this study. The analysis included the following steps: transportation, landfill, processing and fuel combustion at the cement kiln. The energy use and emissions at each step is tracked for the two cases: (1) The Reference Case, where MRF residue is disposed of in a landfill and the cement kiln uses coal as its fuel source, and (2) The SRF Case, in which MRF residue is processed into SRF and used to offset some portion of coal use at the cement kiln. The experimental test burn and accompanying analysis indicate that using MRF residue to produce SRF for use in cement kilns is likely an advantageous alternative to disposal of the residue in landfills. The use of SRF can offset fossil fuel use, reduce CO2 emissions, and divert energy-dense materials away from landfills. For this test-case, the use of SRF offset between 7700 and 8700Mg of coal use, reduced CO2 emissions by at least 1.4%, and diverted over 7950Mg of energy-dense materials away from landfills. In addition, emissions were reduced by at least 19% for SO2, while NOX emissions increased by between 16% and 24%. Changes in emissions of particulate matter, mercury, hydrogen chloride, and total-hydrocarbons were all less than plus or minus 2.2%, however these emissions were not measured at the cement kiln. Co-location of MRFs, SRF production facilities, and landfills can increase the benefits of SRF use even further by reducing transportation requirements. PMID:26187294

  18. [Atmospheric emission of PCDD/Fs from modern dry processing cement kilns with preheating in the southwest area, China].

    PubMed

    Zhang, Xiao-Ling; Lu, Yi; Jian, Chuan; Guo, Zhi-Shun; Zhu, Ming-Ji; Deng, Li; Sun, Jing; Zhang, Qin

    2014-01-01

    Six cement kilns were measured for emissions of PCDD/Fs in the Southwest Area, China. The results indicated that the emission levels of PCDD/Fs were 0.0029-0.0062 ng-m(-3) (Average, 0.0043 ng X m(-3)) from cement kilns which did not burn solid waste, and 0.028 ng X m(-3) from co-processing sewage sludge in cement kiln. The levels of PCDD/Fs emissions from cement manufacturing in the Southwest Area were significantly below the national emissions standard (0.1 ng x m(-3)). Emission factors of PCDD/Fs from the six cement kilns varied between 0.0089 and 0.084 microg x t(-1) cement, which were near or below the lowest emission factor reported by UNEP in 2005. Moreover, the emission factor of PCDD/Fs from co-processing sewage sludge in cement kiln was 7.6 times of the average factors from the other five cement kilns. Moreover,congener distribution of PCDD/F in stack gas from the two types of cement kilns was very different. The results showed that modern dry process cement kilns with preheating have lower emissions of PCDD/Fs. This suggested that the product of co-processing solid waste in cement kilns should be largely enhanced in China in future. PMID:24720182

  19. Cementing: A systematic approach

    SciTech Connect

    Sauer, C.W.; Landrum, W.R.

    1983-10-01

    A step-by-step approach in the form of a cementing process design chart, has been developed for use in Conoco's operating divisions worldwide. The design chart described in this paper includes cement and additive selection and associated hardware for casing and liner cementing operations. Each type of cementing operation is designed to insure the compatibility of hardware and cement slurry components. The process design chart is separated into two major categories: primary cementing; and liner cementing. These categories are separated further into design criteria for cementing each casing string in a well, conductor pipe through production string and each type of liner that is set. Conoco has realized reduced primary cementing costs, up to $35,000.00 per well in some cases, and fewer remedial cement jobs as a result of using practices included in this process design chart. These cost savings can be attributed to the proper cementing practices from many geographic regions which are consolidated into this easy to use cementing design chart. One example of how cement costs can be reduced is by limiting the amount of expensive synthetic cement additives that have been added to less critical pipe strings. These expensive cement additives have been replaced by less expensive natural cement additives that perform just as well, and have resulted in a reduction in the cost per cubic foot of cement slurry.

  20. Analysis on micro cracking process of cement mixed soil

    NASA Astrophysics Data System (ADS)

    Ning, Bao-Kuan; Chen, Si-Li; Huang, Jie

    2008-11-01

    Using the rock meso-mechanics experimental system provided by Key Laboratory of Rock and Soil Mechanics, Institute of Rock and Soil Mechanics, China Academy of Sciences, Wuhan, A series of uniaxial compression tests were performed to analyze the fracturing process and deformation characteristics of cement mixed soil. The meso-fracturing process of cement mixed soil was real-time observed using the microscope and the digital color camera. The stress-strain curves and the corresponding micro-images of specimens in failure process were obtained at the same time. The results are of great scientific references to setting up the mechanical model of the cement mixed soil effectively.

  1. Utilization of flotation wastes of copper slag as raw material in cement production.

    PubMed

    Alp, I; Deveci, H; Süngün, H

    2008-11-30

    Copper slag wastes, even if treated via processes such as flotation for metal recovery, still contain heavy metals with hazardous properties posing environmental risks for disposal. This study reports the potential use of flotation waste of a copper slag (FWCS) as iron source in the production of Portland cement clinker. The FWCS appears a suitable raw material as iron source containing >59% Fe(2)O(3) mainly in the form of fayalite (Fe(2)SiO(4)) and magnetite (Fe(3)O(4)). The clinker products obtained using the FWCS from the industrial scale trial operations over a 4-month period were characterised for the conformity of its chemical composition and the physico-mechanical performance of the resultant cement products was evaluated. The data collected for the clinker products produced using an iron ore, which is currently used as the cement raw material were also included for comparison. The results have shown that the chemical compositions of all the clinker products including those of FWCS are typical of a Portland cement clinker. The mechanical performance of the standard mortars prepared from the FWCS clinkers were found to be similar to those from the iron ore clinkers with the desired specifications for the industrial cements e.g. CEM I type cements. Furthermore, the leachability tests (TCLP and SPLP) have revealed that the mortar samples obtained from the FWCS clinkers present no environmental problems while the FWCS could act as the potential source of heavy metal contamination. These findings suggest that flotation wastes of copper slag (FWCS) can be readily utilised as cement raw material due to its availability in large quantities at low cost with the further significant benefits for waste management/environmental practices of the FWCS and the reduced production and processing costs for cement raw materials. PMID:18384950

  2. The Impact of Mathematical Modeling on the Production of Special Purpose Cement

    E-print Network

    Vuik, Kees

    The Impact of Mathematical Modeling on the Production of Special Purpose Cement Domenico Lahaye in the production industry? Our partnership with Almatis B.V., a special purpose cement manufacturer, resulted with experts in various engineering disciplines. Production of Special Purpose Cement Commonly used cement

  3. Follow up study of workers manufacturing chrysotile asbestos cement products.

    PubMed Central

    Gardner, M J; Winter, P D; Pannett, B; Powell, C A

    1986-01-01

    A cohort study has been carried out of 2167 subjects employed between 1941 and 1983 at an asbestos cement factory in England. The production process incorporated the use of chrysotile asbestos fibre only, except for a small amount of amosite during four months in 1976. Measured airborne fibre concentrations available since 1970 from personal samplers showed mean levels below 1 fibre/ml, although higher levels had probably occurred previously in certain areas of the factory. No excess of lung cancer was observed in the mortality follow up by comparison with either national or local death rates, and analyses of subgroups of the workforce by job, exposure level, duration of employment, duration since entry, or calendar years of employment gave no real suggestion of an asbestos related excess for this cause of death. There was one death from pleural mesothelioma and one with asbestosis mentioned as an associated cause on the death certificate, but neither is thought to be linked to asbestos exposure at this factory. Other suggested asbestos related cancers, such as laryngeal and gastrointestinal, did not show raised risks. Although the durations of exposure were short in this study, the findings are consistent with two other studies of workers exposed to low concentrations of chrysotile fibre in the manufacture of asbestos cement products which reported no excess mortality. PMID:3024695

  4. Characterization of vapor phase mercury released from concrete processing with baghouse filter dust added cement.

    PubMed

    Wang, Jun; Hayes, Josh; Wu, Chang-Yu; Townsend, Timothy; Schert, John; Vinson, Tim; Deliz, Katherine; Bonzongo, Jean-Claude

    2014-02-18

    The fate of mercury (Hg) in cement processing and products has drawn intense attention due to its contribution to the ambient emission inventory. Feeding Hg-loaded coal fly ash to the cement kiln introduces additional Hg into the kiln's baghouse filter dust (BFD), and the practice of replacing 5% of cement with the Hg-loaded BFD by cement plants has recently raised environmental and occupational health concerns. The objective of this study was to determine Hg concentration and speciation in BFD as well as to investigate the release of vapor phase Hg from storing and processing BFD-added cement. The results showed that Hg content in the BFD from different seasons ranged from 0.91-1.44 mg/kg (ppm), with 62-73% as soluble inorganic Hg, while Hg in the other concrete constituents were 1-3 orders of magnitude lower than the BFD. Up to 21% of Hg loss was observed in the time-series study while storing the BFD in the open environment by the end of the seventh day. Real-time monitoring in the bench system indicated that high temperature and moisture can facilitate Hg release at the early stage. Ontario Hydro (OH) traps showed that total Hg emission from BFD is dictated by the air exchange surface area. In the bench simulation of concrete processing, only 0.4-0.5% of Hg escaped from mixing and curing BFD-added cement. A follow-up headspace study did not detect Hg release in the following 7 days. In summary, replacing 5% of cement with the BFD investigated in this study has minimal occupational health concerns for concrete workers, and proper storing and mixing of BFD with cement can minimize Hg emission burden for the cement plant. PMID:24444016

  5. Carbon dioxide capture from a cement manufacturing process

    DOEpatents

    Blount, Gerald C. (North Augusta, SC); Falta, Ronald W. (Seneca, SC); Siddall, Alvin A. (Aiken, SC)

    2011-07-12

    A process of manufacturing cement clinker is provided in which a clean supply of CO.sub.2 gas may be captured. The process also involves using an open loop conversion of CaO/MgO from a calciner to capture CO.sub.2 from combustion flue gases thereby forming CaCO.sub.3/CaMg(CO.sub.3).sub.2. The CaCO.sub.3/CaMg(CO.sub.3).sub.2 is then returned to the calciner where CO.sub.2 gas is evolved. The evolved CO.sub.2 gas, along with other evolved CO.sub.2 gases from the calciner are removed from the calciner. The reactants (CaO/MgO) are feed to a high temperature calciner for control of the clinker production composition.

  6. Cementation process for minerals recovery from Salton Sea geothermal brines

    SciTech Connect

    Maimoni, A.

    1982-01-26

    The potential for minerals recovery from a 1000-MWe combined geothermal power and minerals recovery plant in the Salton Sea is examined. While the possible value of minerals recovered would substantially exceed the revenue from power production, information is insufficient to carry out a detailed economic analysis. The recovery of precious metals - silver, gold, and platinum - is the most important factor in determining the economics of a minerals recovery plant; however, the precious metals content of the brines is not certain. Such a power plant could recover 14 to 31% of the US demand for manganese and substantial amounts of zinc and lead. Previous work on minerals extraction from Salton Sea brines is also reviewed and a new process, based on a fluidized-bed cementation reaction with metallic iron, is proposed. This process would recover the precious metals, lead, and tin present in the brines.

  7. 77 FR 5573 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Portland Cement...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-03

    ...and Production Act of 1993--Portland Cement Association Notice is hereby given that...et seq. (``the Act''), Portland Cement Association (``PCA'') has filed...to this venture. Also, Texas-Lehigh Cement Company, Buda, TX; Arizona Cement...

  8. Production of cements from Illinois coal ash. Technical report, September 1, 1995--November 30, 1995

    SciTech Connect

    Wagner, J.C.; Bhatty, J.I.; Mishulovich, A.

    1995-12-31

    The objective of this program is to convert Illinois coal combustion residues, such as fly ash, bottom ash, and boiler slag, into novel cementitious materials for use in the construction industry. Currently only about 30% of the 5 million tons of these coal combustion residues generated in Illinois each year are utilized, mainly as aggregate. These residues are composed largely Of SiO{sub 2}, Al{sub 2}O{sub 3}, Fe{sub 2}O{sub 3}, MgO, and CaO, which are also the major components of cement. The process being developed in this program will use the residues directly in the manufacture of cement products. Therefore, a much larger amount of residues can be utilized. To achieve the above objective, in the first phase (current year) samples of coal combustion residues will be blended and mixed, as needed, with a lime or cement kiln dust (CKD) to adjust the CaO composition. Six mixtures will be melted in a laboratory-scale furnace at CTL. The resulting products will then be tested for cementitious properties. Two preliminary blends have been tested. One blend used fly ash with limestone, while the other used fly ash with CKD. Each blend was melted and then quenched, and the resulting product samples were ground to a specific surface area similar to portland cement. Cementitious properties of these product samples were evaluated by compression testing of 1-inch cube specimens. The specimens were formed out of cement paste where a certain percentage of the cement paste is displaced by one of the sample products. The specimens were cured for 24 hours at 55{degrees}C and 100% relative humidity. The specimens made with the product samples obtained 84 and 89% of the strength of a pure portland cement control cube. For comparison, similar (pozzolanic) materials in standard concrete practice are required to have a compressive strength of at least 75% of that of the control.

  9. Energy, environmental and greenhouse gas effects of using alternative fuels in cement production

    E-print Network

    Columbia University

    1 Energy, environmental and greenhouse gas effects of using alternative fuels in cement to an increase of AF use from 8.7% to 20.9% of the total energy consumption. 2. One of the alternative fuels used cement industry produces about 3.3 billion tonnes of cement annually. Cement production is energy

  10. 75 FR 453 - FLSMidth, Inc., Cement Division, Product Engineering, Including On-Site Leased Workers of Aerotek...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-05

    ... and Training Administration FLSMidth, Inc., Cement Division, Product Engineering, Including On-Site... Assistance on November 3, 2009, applicable to workers of FLSmidth, Inc., Cement Division, Product Engineering...-site at FLSmidth, Inc., Cement Division, Product Engineering, Bethlehem, Pennsylvania. The...

  11. Functionally-graded fiber-reinforced cement composite: Processing, microstructure, and properties

    E-print Network

    Paulino, Glaucio H.

    Functionally-graded fiber-reinforced cement composite: Processing, microstructure, and properties-graded fiber-reinforced cement composite (FGFRCC). Fiber volume fractions were increased linearly from 0: Fiber-reinforced cement composite (FRCC); Functionally-graded fiber-reinforced cement composite (FGFRCC

  12. India's cement industry: Productivity, energy efficiency and carbon emissions

    SciTech Connect

    Schumacher, Katja; Sathaye, Jayant

    1999-07-01

    Historical estimates of productivity growth in India's cement sector vary from indicating an improvement to a decline in the sector's productivity. The variance may be traced to the time period of study, source of data for analysis, and type of indices and econometric specifications used for reporting productivity growth. Analysis shows that in the twenty year period, 1973 to 1993, productivity in the aluminum sector increased by 0.8% per annum. An econometric analysis reveals that technical progress in India's cement sector has been biased towards the use of energy and capital, while it has been material and labor saving. The increase in productivity was mainly driven by a period of progress between 1983 and 1991 following partial decontrol of the cement sector in 1982. The authors examine the current changes in structure and energy efficiency in the sector. Their analysis shows that the Indian cement sector is moving towards world-best technology, which will result in fewer carbon emissions and more efficient energy use. However, substantial further energy savings and carbon reduction potentials still exist.

  13. Influence of the processed sunflower oil on the cement properties

    NASA Astrophysics Data System (ADS)

    Fleysher, A. U.; Tokarchuk, V. V.; Sviderskiy, V. A.

    2015-01-01

    Used oils (vegetable oil, animal oil, engine oil, etc.), which are essentially industrial wastes, have found application as secondary raw materials in some braches of industry. In particular, the only well-known and commonly-used way of utilizing wastes of vegetable oils is to apply them as raw materials in the production of biodiesel. The goal of the present study is to develop a conceptually new way of vegetable oil wastes utilization in the building industry. The test admixture D-148 was obtained from the processing of wastes of sunflower oil and it mainly consists of fatty acid diethanolamide. The test admixture was added to the cement system for the purpose of studying its influence on water demand, flowability, setting times, compressive strength and moisture adsorption. The test admixture D-148 at the optimal content 0. 2 weight % causes 10% decrease in water demand, 1.7 time increase in flowability (namely spread diameter), 23% increase in grade strength and 34% decrease in moisture adsorption. The results of the present investigation make it possible to consider the final product of the waste sunflower oil processing as multifunctional plasticizing-waterproofing admixture.

  14. Evaluation of cement production using a pressurized fluidized-bed combustor

    SciTech Connect

    DeLallo, M.; Eshbach, R.

    1994-01-01

    There are several primary conclusions which can be reached and used to define research required in establishing the feasibility of using PFBC-derived materials as cement feedstock. 1. With appropriate blending almost any material containing the required cement-making materials can be utilized to manufacture cement. However, extensive blending with multiple materials or the use of ash in relatively small quantities would compromise the worth of this concept. 2. The composition of a potential feedstock must be considered not only with respect to the presence of required materials, but just as significantly, with respect to the presence and concentration of known deleterious materials. 3. The processing costs for rendering the feedstock into an acceptable composition and the energy costs associated with both processing and burning must be considered. It should be noted that the cost of energy to produce cement, expressed as a percentage of the price of the product is higher than for any other major industrial product. Energy consumption is, therefore, a major issue. 4. The need for conformance to environmental regulations has a profound effect on the cement industry since waste materials can neither be discharged to the atmosphere or be shipped to a landfill. 5. Fifth, the need for achieving uniformity in the composition of the cement is critical to controlling its quality. Unfortunately, certain materials in very small concentrations have the capability to affect the rate and extent to which the cementitious compound in portland cement are able to form. Particularly critical are variations in the ash, the sulfur content of the coal or the amount and composition of the stack dust returned to the kiln.

  15. Elemental metals for environmental remediation: learning from cementation process.

    PubMed

    Noubactep, C

    2010-09-15

    The further development of Fe(0)-based remediation technology depends on the profound understanding of the mechanisms involved in the process of aqueous contaminant removal. The view that adsorption and co-precipitation are the fundamental contaminant removal mechanisms is currently facing a harsh scepticism. Results from electrochemical cementation are used to bring new insights in the process of contaminant removal in Fe(0)/H(2)O systems. The common feature of hydrometallurgical cementation and metal-based remediation is the heterogeneous nature of the processes which inevitably occurs in the presence of a surface scale. The major difference between both processes is that the surface of remediation metals is covered by layers of own oxide(s) while the surface of the reducing metal in covered by porous layers of the cemented metal. The porous cemented metal is necessarily electronic conductive and favours further dissolution of the reducing metal. For the remediation metal, neither a porous layer nor a conductive layer could be warrant. Therefore, the continuation of the remediation process depends on the long-term porosity of oxide scales on the metal surfaces. These considerations rationalized the superiority of Fe(0) as remediation agent compared to thermodynamically more favourable Al(0) and Zn(0). The validity of the adsorption/co-precipitation concept is corroborated. PMID:20554389

  16. 76 FR 12370 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Portland Cement...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-07

    ...and Production Act of 1993--Portland Cement Association Notice is hereby given that...et seq. (``the Act''), Portland Cement Association (``PCA'') has filed...Metso Minerals, York, PA; Lehigh Cement Company LLC, Allentown, PA;...

  17. 76 FR 34252 - Notice Pursuant to the National Cooperative Research and Production Act of 1993; Portland Cement...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-13

    ...and Production Act of 1993; Portland Cement Association Notice is hereby given that...et seq. (``the Act''), Portland Cement Association (``PCA'') has filed...specified circumstances. Specifically, Drake Cement, LLC, Scottsdale, AZ; Argos USA...

  18. 75 FR 4423 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Portland Cement...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-27

    ...and Production Act of 1993--Portland Cement Association Notice is hereby given that...et seq. (``the Act''), Portland Cement Association (``PCA'') has filed...circumstances. Specifically, Continental Cement, Hannibal, MO has been added as a...

  19. Reduced carbon emission estimates from fossil fuel combustion and cement production in China

    E-print Network

    2015-01-01

    values. The new, lower estimated cement emissions areand cement emissions in 2013 is 2.49 GtC (2s 5 67.3%); the newand cement production during the period 1950–2013 using independently assessed activity data and two sets of comprehensive new

  20. Cement production is estimated to be responsible for approximately 6 per cent

    E-print Network

    Roe, Paul

    Cement production is estimated to be responsible for approximately 6 per cent of total global greenhouse gas emissions. One of the most promising alternatives to common Portland cement is geopolymer cement, and Australian company Zeobond is a bone fide leader in its manufacture. Geopolymers are formed

  1. Potential use of pyrite cinders as raw material in cement production: results of industrial scale trial operations.

    PubMed

    Alp, I; Deveci, H; Yazici, E Y; Türk, T; Süngün, Y H

    2009-07-15

    Pyrite cinders, which are the waste products of sulphuric acid manufacturing plants, contain hazardous heavy metals with potential environmental risks for disposal. In this study, the potential use of pyrite cinders (PyCs) as iron source in the production of Portland cement clinker was demonstrated at the industrial scale. The chemical and mineralogical analyses of the PyC sample used in this study have revealed that it is essentially a suitable raw material for use as iron source since it contains >87% Fe(2)O(3) mainly in the form of hematite (Fe(2)O(3)) and magnetite (Fe(3)O(4)). The samples of the clinkers produced from PyC in the industrial scale trial operation of 6 months were tested for the conformity of their chemical composition and the physico-mechanical performance of the resultant cement products. The data were compared with the clinker products of the iron ore, which is used as the raw material for the production Portland cement clinker in the plant. The chemical compositions of all the clinker products of PyC appeared to conform to those of the iron ore clinker, and hence, a Portland cement clinker. The mechanical performance of the mortars prepared from the PyC clinker was found to be consistent with those of the industrial cements e.g. CEM I type cements. It can be inferred from the leachability tests (TCLP and SPLP) that PyC could be a potential source of heavy metal pollution while the mortar samples obtained from the PyC clinkers present no environmental problems. These findings suggest that the waste pyrite cinders can be readily used as iron source for the production of Portland cement. The availability of PyC in large quantities at low cost provides further significant benefits for the management/environmental practices of these wastes and for the reduction of mining and processing costs of cement raw materials. PMID:19100685

  2. System for radioactive waste cementation

    SciTech Connect

    Dmitriev, S.A.; Barinov, A.S.; Varlakov, A.P.; Volkov, A.S.; Karlin, S.V.

    1995-12-31

    NPP, research reactors and radiochemical enterprises produce a great amount of liquid radioactive waste (LRW). One of the methods of LRW solidification is cementation. The recent investigations demonstrated possible inclusion of sufficient amount of waste in the cement matrix (up to 20--30 mass% on dry residue). In this case the cementation process becomes competitive with bituminization process, where the matrix can include 40--50 mass% and the solidified product volume is equal to the volume, obtained by cementation. Additionally, the cement matrix in contrast with the bituminous one is unburnable. Many countries are investigating the cementation process. The main idea governing technological process is the waste and cement mixing method and type of mixer. In world practice some principal types of cementation systems are used. The paper describes the SIA Radon industrial plant in Moscow.

  3. Emerging Energy-efficiency and CO{sub 2} Emission-reduction Technologies for Cement and Concrete Production

    SciTech Connect

    Hasanbeigi, Ali; Price, Lynn; Lin, Elina

    2012-04-06

    Globally, the cement industry accounts for approximately 5 percent of current anthropogenic carbon dioxide (CO{sub 2}) emissions. World cement demand and production are increasing significantly, leading to an increase in this industry's absolute energy use and CO{sub 2} emissions. Development of new energy-efficiency and CO{sub 2} emission-reduction technologies and their deployment in the market will be key for the cement industry's mid- and long-term climate change mitigation strategies. This report is an initial effort to compile available information on process description, energy savings, environmental and other benefits, costs, commercialization status, and references for emerging technologies to reduce the cement industry's energy use and CO{sub 2} emissions. Although studies from around the world identify a variety of sector-specific and cross-cutting energy-efficiency technologies for the cement industry that have already been commercialized, information is scarce and/or scattered regarding emerging or advanced energy-efficiency and low-carbon technologies that are not yet commercialized. This report consolidates available information on nineteen emerging technologies for the cement industry, with the goal of providing engineers, researchers, investors, cement companies, policy makers, and other interested parties with easy access to a well-structured database of information on these technologies.

  4. Feasibility of using reject fly ash in cement-based stabilization/solidification processes

    SciTech Connect

    Poon, C.S.; Qiao, X.C.; Cheeseman, C.R.; Lin, Z.S.

    2006-01-15

    Stabilization/solidification (s/s) has been routinely used for the final treatment of hazardous wastes prior to land disposal. These processes involve adding one or more solidifying reagents into the waste to transform it into a monolithic solid with improved structural integrity. Cement-based systems with partial replacement by pulverized fuel ash (PFA) have been widely used to minimize leaching of contaminants from hazardous wastes. The finer fraction of PFA ({lt}45 {mu} m, fine fly ash, MA), produced by passing the raw ash through a classifying process is commonly used in s/s processes. Low-grade fly ash is rejected (rFA) from the ash classifying process, and is largely unused due to high carbon content and large particle size but represents a significant proportion of PFA. This paper presents experimental results of a study that has assessed the feasibility of using rFA in the cement-based s/s of a synthetic heavy metal waste. Results were compared to mixes containing fFA. The strength results show that cement-based waste forms with rFA replacement are suitable for disposal at landfill and that the addition of heavy metal sludge can increase the degree of hydration of fly ash and decrease the porosity of samples. Adding Ca(OH){sub 2} and flue gas desulphurization sludge reduces the retarding effect of heavy metals on strength development. The results of the Toxicity Characteristic Leaching Procedure and Dynamic Leach Test show that rFA can be used in cement-based s/s wastes without compromising performance of the product.

  5. DEVELOPMENT OF A POLYMERIC CEMENTING AND ENCAPSULATING PROCESS FOR MANAGING HAZARDOUS WASTES

    EPA Science Inventory

    A process using polymeric materials to cement and encapsulate dry hazardous waste was researched, developed, and evaluated. The process involves cementing particulates of waste into 500 to 1000 pound agglomerates, and then fusing a plastic jacket onto the agglomerate surfaces, th...

  6. ASBESTOS-CEMENT PRODUCTS IN CONTACT WITH DRINKING WATER: SEM OBSERVATIONS

    EPA Science Inventory

    In studying the health effects of asbestos fibers ingested in drinking water it is important to know whether water can corrode the surface of asbestos-cement products to facilitate the release of the fibers to the water. Also, in the case of asbestos-cement pipe, it is important ...

  7. Emerging Energy-efficiency and CO2 Emission-reduction Technologies for Cement and Concrete Production

    E-print Network

    Hasanbeigi, Ali

    2013-01-01

    and hydration products to achieve cements and concretes withhydration, the paste hardens and gains strength to form the rock-like mass known as concrete (concrete performance through incorporation of nanoparticles and chemical admixtures Better understanding of cementitious materials through nanoscale investigations of cement hydration

  8. Production of cements from Illinois coal ash. Final technical report, September 1, 1995--August 31, 1996

    SciTech Connect

    Wagner, J.C.; Bhatty, J.L.; Mishulovich, A.

    1997-05-01

    The objective of this program is to convert Illinois coal combustion residues, such as fly ash, bottom ash, and boiler slag, into novel cementitious materials for use in the construction industry. These residues are composed largely of SiO{sub 2}, Al{sub 2}O{sub 3}, Fe{sub 2}O{sub 3}, MgO, and CaO, which are also the major components of cement. Since the residues are used as an integral component of the cement and not just as additives to concrete, larger amounts of the residues can be utilized. The process uses submerged combustion to melt blends of coal combustion residues with lime, clay, and/or sand. The submerged combustion melter utilizes natural gas-oxidant firing directly into a molten bath to provide efficient melting of mineral-like materials. Use of this melter for cement production has many advantages over rotary kilns including very little, if any, grinding of the feed material, very low emissions, and compact size. During the first year of the program, samples of coal combustion residues were blended and mixed, as needed; with lime, clay, and/or sand to adjust the composition. Six mixtures, three with fly ash and three with bottom ash, were melted in a laboratory-scale furnace. The resultant products were used in mortar cubes and bars which were subjected to ASTM standard tests of cementitious properties. In the hydraulic activity test, mortar cubes were found to have a strength comparable to standard mortar cements. In the compressive strength test, mortar cubes were found to have strengths that exceeded ASTM blended cement performance specifications. In the ASR expansion test, mortar bars were subjected to alkali-silica reaction-induced expansion, which is a problem for siliceous aggregate-based concretes that are exposed to moisture. The mortar bars made with the products inhibited 85 to 97% of this expansion. These results show that residue-based products have an excellent potential as ASR-preventing additions in concretes.

  9. Improved control of the finish grinding process in cement manufacture

    SciTech Connect

    Menacho, J.M.; Austin, L.G.; Cuhadaroglu, M.S. . Dept. of Mineral Processing)

    1985-01-01

    Activities developed on Task 6 of the Cement Clinker Project from July 1, 1985 to September 30, 1985 are described in this progress report. Results on eight continuous ball mill tests are included. Experimentation was performed in a 0.99 m diameter air-swept mill at the Kennedy Van Saun facilities in Danville. In the first four runs, the effect of production rate on size distribution of product was tested for the powder filling level around 0.83. In the other tests, the powder filling was changed between 0.7 and 1.25. A preliminary analysis of the results indicates that the internal classification curve is moving in a narrow band even when the product size distribution is strongly affected by the different experimented condition. Also the direct scale-up results from the 8 inch diameter batch mill to the 0.99 mill diameter in batch mode is reported. Predictions overestimate capacity for short times of grinding but they are in good agreement for long times. The presence of components having large and small rate of breakage and occurrence of abnormal breakage are discussed. Future work includes detailed analysis of the data and simulation of continuous test results.

  10. Heuristic economic assessment of the Afghanistan construction materials sector: cement and dimension stone production

    USGS Publications Warehouse

    Mossotti, Victor G.

    2014-01-01

    Over the past decade, the U.S. Government has invested more than $106 billion for physical, societal, and governmental reconstruction assistance to Afghanistan (Special Inspector General for Afghanistan Reconstruction, 2012a). This funding, along with private investment, has stimulated a growing demand for particular industrial minerals and construction materials. In support of this effort, the U.S. Geological Survey released a preliminary mineral assessment in 2007 on selected Afghan nonfuel minerals (Peters and others, 2007). More recently, the 2007 mineral assessment was updated with the inclusion of a more extensive array of Afghan nonfuel minerals (Peters and others, 2011). As a follow-up on the 2011 assessment, this report provides an analysis of the current use and prospects of the following Afghan industrial minerals required to manufacture construction materials: clays of various types, bauxite, gypsum, cement-grade limestone, aggregate (sand and gravel), and dimension stone (sandstone, quartzite, granite, slate, limestone, travertine, marble). The intention of this paper is to assess the: Use of Afghan industrial minerals to manufacture construction materials, Prospects for growth in domestic construction materials production sectors, Factors controlling the competitiveness of domestic production relative to foreign imports of construction materials, and Feasibility of using natural gas as the prime source of thermal energy and for generating electrical energy for cement production. The discussion here is based on classical principles of supply and demand. Imbedded in these principles is an understanding that the attributes of supply and demand are highly variable. For construction materials, demand for a given product may depend on seasons of the year, location of construction sites, product delivery time, political factors, governmental regulations, cultural issues, price, and how essential a given product might be to the buyer. Moreover, failure on the supply side to mirror such attributes can be deal-breakers in a transaction. For qualitative interpretation of the findings in this report, the value chain was used to conceptualize the relation between supply and demand. Although quantitative data on the Afghan construction materials sector have been hard to come by, the premise herein was that qualitative aspects of supply and demand are revealed by following the flow of funding through projects of varying sizes. It was found that the spectrum of attributes on the demand side of large multimillion dollar reconstruction projects is generally high dimensional, distributed over a broad line of construction materials at diverse locations, and in varying quantities. As interpreted herein, project funds dispensed at the higher hierarchical levels of a project are often concentrated on procurement of construction materials and services at the upper end of the value chain. In contrast, project funds dispensed at the lower hierarchical levels are disseminated across a multiplicity of subprojects, thus restricting project acquisitions to the lower end of the value chain. Evidence suggests that under the current conditions in Afghanistan producers of construction materials at the lower end of the value chain (adobe brick, aggregate, low-end marble products) can successfully compete in local markets and turn a profit. In contrast, producers of energy-intensive products such as cement will continue to face intense competition from imports, at least in the near-term. In the long-term, as infrastructure issues are resolved, and as business conditions in Afghanistan improve, domestic producers will have a locational advantage in establishing a solid niche in their respective home markets. In the process of tendering properties for cement production, the pivotal issues of abundant, reliable, and cost-effective thermal and electrical energy sources for cement production have become prominent. Over the past 50 years, powdered coal and natural gas have been proven to be excellent fuels for firing kilns at cement plants, and bot

  11. Electrical conductivity is a parameter that can be used to monitor the entire hardening process of oilwell cement slurries. The theo-

    E-print Network

    Backe, Knut

    process of oilwell cement slurries. The theo- retical relationship among conductivity, porosity, cement and that rapid hydration will reduce the risk of gas migration. Introduction The main purposes of oilwell cements hardening process of oilwell cement slurries is important for successful cementing operations. Several

  12. Manufacture and properties of fluoride cement

    NASA Astrophysics Data System (ADS)

    Malata-Chirwa, Charles David

    This research work aimed at characterising composition, hydration and physical properties of fluoride cement, by studying samples of the cement obtained from Malawi, and comparing them to ordinary Portland cement. By confirming the suitable characteristics of fluoride cement through this work, the results of the research work provide a good basis for the wider adoption of fluoride cement as an alternative to ordinary Portland cement, especially in developing economies. Numerous accounts have been cited regarding the production and use of fluoride cement. Since there have not been conclusive agreement as to its properties, this study was limited to the theories of successful incorporation of fluoride compounds in the manufacture of fluoride cement. Hence, the properties and characteristics reported in this study relate to the cement currently manufactured in Malawi, and, on a comparative basis only, to that manufactured in other parts of the world. Samples of the fluoride cement used in the study were obtained by synthetic manufacture of the cement using common raw materials for the manufacture of fluoride cement that is limestone, silica sand, and fluorspar. These samples were subjected to several comparative tests used to characterise cements including examination under x-ray diffractometer, scanning electron microscopy and tests for setting time and compressive strength. Under similar laboratory conditions, it was possible to prove that fluoride cement hardens more rapidly than ordinary Portland cement. Also observed during the experimental work is that fluoride cement develops higher compressive strengths than ordinary Portland cement. The hardening and setting times are significantly different between the two cements. Also the nature of the hydration products, that is the microstructural development is significantly different in the two cements. The differences brought about between the two cements are because of the presence of fluorine during the clinkering process. It was observed in the laboratory simulated production of fluoride cement, that the clinkering temperature is much lower (around 1 170 °C) compared to that for the production of ordinary Portland cement. The other observed differences were attributed to the different mineralogical composition as a result of fluoride incorporation into the cement. While fluorine content is very minimal in fluoride cement, not more than 2 %, the resulting cementitious products are altered significantly as was observed from the study. Part of the experimental results has been used as reference material in the preparation of a draft Malawi Standard on fluoride cement. This draft standard will be submitted to the Malawi Bureau of Standards for further processing before it can be officially endorsed as a Malawi Standard.

  13. In situ monitoring of the hydration process of K-PS geopolymer cement with ESEM

    SciTech Connect

    Sun Wei; Zhang Yunsheng; Lin Wei; Liu Zhiyong

    2004-06-01

    Environmental scanning electron microscope (ESEM) was used to in situ quantitatively study the hydration process of K-PS geopolymer cement under an 80% RH environment. An energy dispersion X-ray analysis (EDXA) was also employed to distinguish the chemical composition of hydration product. The ESEM micrographs showed that metakaolin particles pack loosely at 10 min after mixing, resulting in the existence of many large voids. As hydration proceeds, a lot of gels were seen and gradually precipitated on the surfaces of these particles. At later stage, these particles were wrapped by thick gel layers and their interspaces were almost completely filled. The corresponding EDXA results illustrated that the molar ratios of K/Al increase while Si/Al decrease with the development of hydration. As a result, the molar ratios of K/Al and Si/Al of hydration products at an age of 4 h amounted to 0.99 and 1.49, respectively, which were close to the theoretical values (K/Al=1.0, Si/Al=1.0 for K-PS geopolymer cement paste). In addition, well-developed crystals could not been found at any ages; instead, spongelike amorphous gels were always been observed.

  14. PIXE characterization of by-products resulting from the zinc recycling of industrial cemented carbides

    NASA Astrophysics Data System (ADS)

    Freemantle, C. S.; Sacks, N.; Topic, M.; Pineda-Vargas, C. A.

    2015-11-01

    By-product materials of the widely used zinc recycling process of cemented carbides have been studied. Scanning electron microscopy and micro-PIXE techniques have identified elemental concentrations, distributions and purity of by-product materials from an industrial zinc recycling plant. Cobalt surface enrichment, lamellar microstructures of varying composition, including alternating tungsten carbide (WC) grains and globular cobalt, and regions of excess zinc contamination were found in materials with incomplete zinc penetration. Liquid Co-Zn formation occurred above 72 wt.% Zn at the furnace temperature of 930 °C, and was extracted towards the surface of poorly zinc infiltrated material, primarily by the vacuum used for zinc distillation. Surface enrichment was not observed in material that was zinc infiltrated to the sample center, which was more friable and exhibited more homogeneous porosity and elemental concentrations. The result of incomplete zinc infiltration was an enriched surface zone of up to 60 wt.% Co, compared to an original sample composition of ?10-15 wt.% Co. The impact on resulting powders could be higher or inhomogeneous cobalt content, as well as unacceptably high zinc concentrations. PIXE has proven it can be a powerful technique for solving industrial problems in the cemented carbide cutting tool industry, by identifying trace elements and their locations (such as Zn to 0.1 wt.% accuracy), as well as the distribution of major elements within WC-Co materials.

  15. Minerals recovery from Salton Sea geothermal brines: a literature review and proposed cementation process

    SciTech Connect

    Maimoni, A.

    1982-01-01

    The potential for minerals recovery from a 1000-MWe combined geothermal power and minerals recovery plant in the Salton Sea is examined. While the possible value of minerals recovered would substantially exceed the revenue from power production, information is insufficient to carry out a detailed economic analysis. The recovery of precious metals - silver, gold and platinum - is the most important factor in determining the economics of a minerals recovery plant. However, the precious metal content of the brines is not certain. Such a power plant could recover 14 to 31% of the US demand for manganese and substantial amounts of zinc and lead. Previous work on minerals extraction from Salton Sea brines is reviewed and a new process, based on a fluidized-bed cementation reaction with metallic iron, is proposed. This process would recover the precious metals, lead and tin present in the brines.

  16. Effect of carbon dioxide injection on production of wood cement composites from waste medium density fiberboard (MDF).

    PubMed

    Qi, H; Cooper, P A; Wan, H

    2006-01-01

    The possibility of recycling waste medium density fiberboard (MDF) into wood-cement composites was evaluated. Both new fibers and recycled steam exploded MDF fibers had poor compatibility with cement if no treatment was applied, due to interference of the hydration process by the water soluble components of the fiber. However, this issue was resolved when a rapid hardening process with carbon dioxide injection was adopted. It appears that the rapid carbonation allowed the board to develop considerable strength before the adverse effects of the wood extractives could take effect. After 3-5 min of carbon dioxide injection, the composites reached 22-27% of total carbonation and developed 50-70% of their final (28-day) strength. Composites containing recycled MDF fibers had slightly lower splitting tensile strength and lower tensile toughness properties than those containing new fibers especially at a high fiber/cement ratio. Composites containing recycled MDF fibers also showed lower values of water absorption. Unlike composites cured conventionally, composites cured under CO(2) injection developed higher strength and toughness with increased fiber content. Incorporation of recycled MDF fibers into wood cement composites with CO(2) injection during the production stage presents a viable option for recycling of this difficult to manage waste material. PMID:16046114

  17. Cement and concrete

    NASA Technical Reports Server (NTRS)

    Corley, Gene; Haskin, Larry A.

    1992-01-01

    To produce lunar cement, high-temperature processing will be required. It may be possible to make calcium-rich silicate and aluminate for cement by solar heating of lunar pyroxene and feldspar, or chemical treatment may be required to enrich the calcium and aluminum in lunar soil. The effects of magnesium and ferrous iron present in the starting materials and products would need to be evaluated. So would the problems of grinding to produce cement, mixing, forming in vacuo and low gravity, and minimizing water loss.

  18. Processing of Sugarcane Bagasse ash and Reactivity of Ash-blended Cement Mortar

    NASA Astrophysics Data System (ADS)

    Ajay, Goyal; Hattori, Kunio; Ogata, Hidehiko; Ashraf, Muhammad

    Sugarcane bagasse ash (SCBA), a sugar-mill waste, has the potential of a partial cement replacement material if processed and obtained under controlled conditions. This paper discusses the reactivity of SCBA obtained by control burning of sugarcane bagasse procured from Punjab province of India. X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques were employed to ascertain the amorphousness and morphology of the minerals ash particles. Destructive and non-destructive tests were conducted on SCBA-blended mortar specimens. Ash-blended cement paste specimens were analyzed by XRD, thermal analysis, and SEM methods to evaluate the hydration reaction of SCBA with cement. Results showed that the SCBA processed at 600°C for 5 hours was reactive as ash-blended mortar specimens with up to 15% substitution of cement gave better strength than control specimens.

  19. HAZARDOUS WASTE COMBUSTION IN INDUSTRIAL PROCESSES: CEMENT AND LIME KILNS

    EPA Science Inventory

    The report summarizes the results of several studies relating to hazardous waste combustion in cement and lime kilns. The tests included in the study are four kilns tested by the U.S. Environmental Protection Agency, four kilns tested by State agencies or the kiln operator, two C...

  20. Sculpting with Cement.

    ERIC Educational Resources Information Center

    Olson, Lynn

    1983-01-01

    Cement offers many creative possibilities for school art programs. Instructions are given for sculpting with fiber-cement and sand-cement, as well as for finishing processes and the addition of color. Safety is stressed. (IS)

  1. Assessing the relative importance of compaction processes and cementation to reduction of porosity in sandstones

    SciTech Connect

    Houseknecht, D.W.

    1987-06-01

    At the depositional surface, well-sorted sand has approximately 40% porosity. During burial diagenesis, that porosity is reduced by mechanical compaction, intergranular pressure solution, and cementation. Mechanical compaction and intergranular pressure solution can both be considered compactional processes because they irreversibly reduce the intergranular volume of sand. In contrast, cementation occludes, but does not reduce, intergranular volume. The relative importance of compactional processes and cementation to porosity reduction can be quantified using a graph of intergranular volume vs. cement. This diagram can be used to evaluate which diagenetic processes have been most influential to intergranular porosity reduction and to determine why some sandstones retain better reservoir quality than others. The diagram can also be used to reconstruct pathways taken by sandstones during burial diagenesis. Results of applying this technique to data from the Nugget Sandstone and Bromide sandstone (Simpson Group) indicate that mechanical compaction and intergranular pressure solution were much more important than cementation in determining ultimate porosity. Moreover, the best porosity is preserved in samples that have undergone the least intergranular pressure solution. These conclusions emphasize the importance of integrating an evaluation of these compactional processes into analyses of reservoir sandstones and into models of burial diagenesis. 6 figures.

  2. Using the low-temperature plasma in cement production

    NASA Astrophysics Data System (ADS)

    Sazonova, N. A.; Skripnikova, N. K.

    2015-11-01

    The calculation of the raw-material mixtures and mineralogical composition of the cement clinkers which are synthezed on their base taking into account the disbalanced crystallization of the melting and glassing under conditions of the low-temperature plasma was performed. The difference of the actual values from the calculated ones is 0.69-3.73%. The composition which is characterized as the saturation coefficient 0,88; the silicate module - 3.34, the alumina module - 2.52 in melting of which the alite in amount 78.7%; 3CaO·SiO2 - 4%; 3CaO·Al2O3 - 9.8%; 12CaO·7Al2O3 -2.9%; CaOfree - 1% formed using the lime-stone from the quarry «Pereval» in the town of Slyudyanka and the clay from the deposit «Maximovski» in Irkutsk Region is considered as the optimal one. The structure of the melted clinker is represented as the metastable minerals of alite in the lamellar form with the dimensions up to (3-20)×(80-400) ?m and the ratio of length to width 26.6-133. The elongated crystal form may stipulate the high cement activity based on the melted clinkers, which is 82.7-84.2 MPa. Valid- ing the revealed high activity of the viscous substance was confirmed by the results of the scanning electronic microscopy, X-ray phase analysis, with using of which the quantitative and qualitative analyses of the clinker minerals having the deformed crystalic lattice; were performed the morphology of the minerals in the clinker and cement stone, received on its ground, was studied.

  3. Dolomite magnesium oxychloride cement properties control method during its production

    NASA Astrophysics Data System (ADS)

    Chernykh, T. N.; Nosov, A. V.; Kramar, L. Ya

    2015-01-01

    The work considers the possibility of reducing the decomposition temperature of MgCO3 in dolomite rock, provides the results of studies of the effect of various additives and enhancers on the decomposition of magnesium and calcium components of dolomite. Chlorides additives are the most promising for dolomite rocks roast intensification. They allow shifting the MgCO3 decomposition to lower temperatures, without exerting a significant influence on the decomposition of CaCO3. Introduction of additives-enhancers is found to be an effective method of controlling the properties of dolomite MOC during roasting, producing high-strength dolomite magnesium oxychloride cements with change in volume during solidification.

  4. Towards optimization of the silanization process of hydroxyapatite for its use in bone cement formulations.

    PubMed

    Cisneros-Pineda, Olga G; Herrera Kao, Wilberth; Loría-Bastarrachea, María I; Veranes-Pantoja, Yaymarilis; Cauich-Rodríguez, Juan V; Cervantes-Uc, José M

    2014-07-01

    The aim of this work was to provide some fundamental information for optimization of silanization of hydroxyapatite intended for bone cement formulations. The effect of 3-(trimethoxysilyl) propyl methacrylate (MPS) concentration and solvent system (acetone/water or methanol/water mixtures) during HA silanization was monitored by X-ray diffraction (XRD), FTIR spectroscopy and EDX analysis. The effect of silanized HA on the mechanical properties of acrylic bone cements is also reported. It was found that the silanization process rendered hydroxyapatite with lower crystallinity compared to untreated HA. Through EDX, it was observed that the silicon concentration in the HA particles was higher for acetone-water than that obtained for methanol-water system, although the mechanical performance of cements prepared with these particles exhibited the opposite behavior. Taking all these results together, it is concluded that methanol-water system containing MPS at 3wt.% provides the better results during silanization process of HA. PMID:24857478

  5. ELIMINATION OF WATER POLLUTION BY RECYCLING CEMENT PLANT KILN DUST

    EPA Science Inventory

    Excessive amounts of alkalies can have deleterious effects upon the process of cement manufacture and the product. Normally much of the alkali present in cement raw materials is volatilized in the cement kiln and condenses on the particles of kiln dust which are carried out of th...

  6. Cementation of Colloidal Particles on Electrodes in a Galvanic Microreactor

    E-print Network

    Aksay, Ilhan A.

    processing, galvanic corrosion, cementation, reaction products INTRODUCTION Colloidal crystals have16,17 have been well-understood, the effect of the reaction parameters on the cementationCementation of Colloidal Particles on Electrodes in a Galvanic Microreactor Linda Jan, Christian

  7. Technological features of cementation of liquid organic wastes from radiochemical production and NPP

    SciTech Connect

    Belyaeva, T.B.; Kiselev-Dmitriev, A.L.; Masanov, O.L.

    1993-12-31

    One method to manage liquid radioactive wastes is to incorporate them into inorganic materials. At VNINM, work was performed to cement spent oils and extractants and to determine final product properties. Attention was paid to a choice of emulsifiers. Parameters investigated included emulsifier availability, stability, and incorporability into a matrix material.

  8. Use of Ceramic Material (cement Clinker) for the Production of Biodiesel

    NASA Astrophysics Data System (ADS)

    Soni, Sunny; Agarwal, Madhu

    Biodiesel is a renewable liquid fuel made from natural, renewable biological sources such as edible and non edible oils. Over the last years, biodiesel has gained more market due to its benefits and because it appears as the natural substitute for diesel. Reasons for growing interest in biodiesel include its potential for reducing noxious emissions, potential contributions to rural economic development, as an additional demand center for agricultural commodities, and as a way to reduce reliance on foreign oil. Biodiesel was prepared from soybean oil by transesterification with methanol in the presence of cement clinker. Cement clinker was examined as a catalyst for a conversion of soybean oil to fatty acid methyl esters (FAMEs). It can be a promising heterogeneous catalyst for the production of biodiesel fuels from soybean oil because of high activity in the conversion and no leaching in the transesterification reaction. The reaction conditions were optimized. A study for optimizing the reaction parameters such as the reaction temperature, and reaction time, was carried out. The catalyst cement clinker composition was characterized by XRF. The results demonstrate that the cement clinker shows high catalytic performance & it was found that the yield of biodiesel can reach as high as 84.52% after 1 h reaction at 65°C, with a 6:1 molar ratio of methanol to oil, 21 wt% KOH/cement clinker as catalyst.

  9. Capture of green-house carbon dioxide in Portland cement

    SciTech Connect

    Wagh, A.S.; Singh, D.; Pullockaran, J.; Knox, L.

    1993-12-31

    A novel process has been developed to sequester green-house carbon dioxide produced by the cement industry in precast cement products. Typically, 10--24 wt % of CO{sub 2} produced by calcination of calcium carbonate during clinkering of the cement may be captured. The carbonation process also cures the cement paste within minutes into hard bodies. The process maintains high pH conditions during curing, to allow conventional steel reinforcement of concrete. The process will save time and money to the cement industry, and at the same time, help them to comply with the Clean Air Act by sequestering the green-house carbon dioxide.

  10. ENVIRONMENTAL CONSIDERATIONS OF SELECTED ENERGY CONSERVING MANUFACTURING PROCESS OPTIONS: VOLUME X. CEMENT INDUSTRY REPORT

    EPA Science Inventory

    This study assesses the likelihood of new process technology and new practices being introduced by energy intensive industries and explores the environmental impacts of such changes. Volume 10 deals with the cement industry and examines four options: (1) suspension preheater, (2)...

  11. INDUSTRIAL PROCESS PROFILES FOR ENVIRONMENTAL USE: CHAPTER 21. THE CEMENT INDUSTRY

    EPA Science Inventory

    The catalog of Industrial Process Profiles for Environmental Use was developed as an aid in defining the environmental impacts of industrial activity in the United States. Entries for each industry are in consistent format and form separate chapters of the study. The cement indus...

  12. Effect of operating parameters on the removal of bone cement by a sawing process.

    PubMed

    James, Thomas P; Sheehan, Brian; Sagar, Amrit

    2014-03-01

    The number of total knee arthroplasty revision surgeries is increasing each year, driven by the wide availability and general acceptance of the procedure accompanied by an aging population of implants. Metal implants are often secured to the tibial plateau by a mantle of poly(methyl methacrylate) bone cement. During revision surgery, a power oscillating saw is used to remove bone cement while preparing the boney bed. Presently, there are no published studies on the mechanics of bone cement removal by a sawing process. The aim of this research was to quantify the effect of blade speed and applied thrust force on the volumetric cutting rate of bone cement. A custom reciprocating saw with variable stroke length was used to conduct a three-factor design of experiments. Two levels, without center-points, were sufficient to model the effect of stroke length (6.75, 10.13 mm), thrust force (11, 19 N), and reciprocating speed in strokes per minute (6000, 8000 SPM) on cutting rate. The results indicate that each of the three parameters had a significant impact on cutting rate (p < 0.001), with a linear relationship between both force and cutting rate (r = 0.98) and blade speed and cutting rate (r = 0.98). For the parameters considered, increasing the reciprocating speed had the most significant effect on cutting rate. For example, while holding force and stroke length constant (11 N, 10.13 mm), an increase in speed from 6000 to 8000 SPM nearly doubled the cutting rate of bone cement. A cutting rate model was developed by regression analysis of the experimental data and validated through additional experiments. The model has applications in haptic feedback for surgical simulators to differentiate between the cutting rates of bone and bone cement during virtual training of resident surgeons. PMID:24562099

  13. Recycling of the product of thermal inertization of cement-asbestos for various industrial applications

    SciTech Connect

    Gualtieri, Alessandro F.; Giacobbe, Carlotta; Sardisco, Lorenza; Saraceno, Michele; Lassinantti Gualtieri, Magdalena; Cavenati, Cinzia; Zanatto, Ivano

    2011-01-15

    Recycling of secondary raw materials is a priority of waste handling in the countries of the European community. A potentially important secondary raw material is the product of the thermal transformation of cement-asbestos, produced by prolonged annealing at 1200-1300 {sup o}C. The product is chemically comparable to a Mg-rich clinker. Previous work has assured the reliability of the transformation process. The current challenge is to find potential applications as secondary raw material. Recycling of thermally treated asbestos-containing material (named KRY.AS) in traditional ceramics has already been studied with successful results. The results presented here are the outcome of a long termed project started in 2005 and devoted to the recycling of this secondary raw materials in various industrial applications. KRY.AS can be added in medium-high percentages (10-40 wt%) to commercial mixtures for the production of clay bricks, rock-wool glasses for insulation as well as Ca-based frits and glass-ceramics for the production of ceramic tiles. The secondary raw material was also used for the synthesis of two ceramic pigments; a green uvarovite-based pigment [Ca{sub 3}Cr{sub 2}(SiO{sub 4}){sub 3}] and a pink malayaite-based pigment [Ca(Sn,Cr)SiO{sub 5}]. The latter is especially interesting as a substitute for cadmium-based pigments. This work also shows that KRY.AS can replace standard fillers in polypropylene plastics without altering the properties of the final product. For each application, a description and relevant results are presented and discussed.

  14. Recycling of the product of thermal inertization of cement-asbestos for various industrial applications.

    PubMed

    Gualtieri, Alessandro F; Giacobbe, Carlotta; Sardisco, Lorenza; Saraceno, Michele; Gualtieri, Magdalena Lassinantti; Lusvardi, Gigliola; Cavenati, Cinzia; Zanatto, Ivano

    2011-01-01

    Recycling of secondary raw materials is a priority of waste handling in the countries of the European community. A potentially important secondary raw material is the product of the thermal transformation of cement-asbestos, produced by prolonged annealing at 1200-1300 °C. The product is chemically comparable to a Mg-rich clinker. Previous work has assured the reliability of the transformation process. The current challenge is to find potential applications as secondary raw material. Recycling of thermally treated asbestos-containing material (named KRY·AS) in traditional ceramics has already been studied with successful results. The results presented here are the outcome of a long termed project started in 2005 and devoted to the recycling of this secondary raw materials in various industrial applications. KRY·AS can be added in medium-high percentages (10-40 wt%) to commercial mixtures for the production of clay bricks, rock-wool glasses for insulation as well as Ca-based frits and glass-ceramics for the production of ceramic tiles. The secondary raw material was also used for the synthesis of two ceramic pigments; a green uvarovite-based pigment [Ca(3)Cr(2)(SiO(4))(3)] and a pink malayaite-based pigment [Ca(Sn,Cr)SiO(5)]. The latter is especially interesting as a substitute for cadmium-based pigments. This work also shows that KRY·AS can replace standard fillers in polypropylene plastics without altering the properties of the final product. For each application, a description and relevant results are presented and discussed. PMID:20708915

  15. 75 FR 453 - FLSMidth, Inc., Cement Division, Product Engineering, Including On-Site Leased Workers of Aerotek...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-05

    ...TA-W-72,048] FLSMidth, Inc., Cement Division, Product Engineering, Including On-Site Leased Workers of Aerotek Contract Engineering, Allied Personnel Services, Eastern Engineering, Hobbie Professional Services, Mccallion Staffing...

  16. Silicon production process evaluations

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Chemical engineering analyses involving the preliminary process design of a plant (1,000 metric tons/year capacity) to produce silicon via the technology under consideration were accomplished. Major activities in the chemical engineering analyses included base case conditions, reaction chemistry, process flowsheet, material balance, energy balance, property data, equipment design, major equipment list, production labor and forward for economic analysis. The process design package provided detailed data for raw materials, utilities, major process equipment and production labor requirements necessary for polysilicon production in each process.

  17. Calcination of kaolinite clay particles for cement production: A modeling study

    SciTech Connect

    Teklay, Abraham; Yin, Chungen; Rosendahl, Lasse; Bøjer, Martin

    2014-07-01

    Kaolinite rich clay particles calcined under certain conditions can attain favorable pozzolanic properties and can be used to substitute part of the CO{sub 2} intensive clinker in cement production. To better guide calcination of a clay material, a transient one-dimensional single particle model is developed, which fully addresses the conversion process of raw kaolinite particles suspended in hot gas. Particles are discretized into a number of spherical cells, on each of which mass, momentum, energy and species conservation equations are numerically solved by using the finite volume method. Reactions considered in the model include dehydration, dehydroxylation and various phase transformations. Thermogravimetric analysis is used to determine reaction kinetic data required as inputs in the model and to validate the model. Finally, model-based sensitivity analysis is performed, from which quantitative guidelines for calcination condition optimization are derived. - Highlights: • A general 1D mathematical model for single clay particle calcination is developed. • The model fully addresses momentum, heat and mass transfer and all the reactions. • Experiments are performed to determine kinetic data of the key reactions. • The model is verified by different means, including experimental results. • Sensitivity study is done to address key assumptions and derive useful guidelines.

  18. Process, Product, and Playmaking

    ERIC Educational Resources Information Center

    Fisher, Maisha T.; Purcell, Susie Spear; May, Rachel

    2009-01-01

    This article examines relationships among process, product, and playmaking in a southeastern playwriting and performance program for teen girls, Playmaking for Girls (PFG). The authors have chosen to focus on tensions between process and product. Such tensions are present in the challenges teachers experience when privileging student-centered…

  19. Cement sealing

    SciTech Connect

    Cowan, K.M.

    1991-05-21

    This patent describes a process for cementing a selected part of a well. It comprises: determining a surfactant capable of reducing the volumetric shrinkage of an aqueous cement slurry from about 10% to about 75% during setting and hardening, ascertaining the amount of the surfactant necessary to accomplish the reduction in volumetric shrinkage, and injecting the slurry with the necessary amount of surfactant into the selected part of the well.

  20. Techno-economic study of the calcium looping process for CO2 capture from cement and biomass power plants 

    E-print Network

    Ozcan, Dursun Can

    2014-11-27

    The first detailed systematic investigation of a cement plant with various carbon capture technologies has been performed. The calcium looping (Ca-looping) process has emerged as a leading option for this purpose, since ...

  1. Energy Efficient Microwave Hybrid Processing of Lime for Cement, Steel, and Glass Industries

    SciTech Connect

    Fall, Morgana L; Yakovlev, Vadim; Sahi, Catherine; Baranova, Inessa; Bowers, Johnney G; Esquenazi , Gibran L

    2012-02-10

    In this study, the microwave materials interactions were studied through dielectric property measurements, process modeling, and lab scale microwave hybrid calcination tests. Characterization and analysis were performed to evaluate material reactions and energy usage. Processing parameters for laboratory scale and larger scale calcining experiments were developed for MAT limestone calcination. Early stage equipment design concepts were developed, with a focus on microwave post heating treatment. The retrofitting of existing rotary calcine equipment in the lime industry was assessed and found to be feasible. Ceralink sought to address some of the major barriers to the uptake of MAT identified as the need for (1) team approach with end users, technology partners, and equipment manufacturers, (2) modeling that incorporates kiln materials and variations to the design of industrial microwave equipment. This project has furthered the commercialization effort of MAT by working closely with an industrial lime manufacturer to educate them regarding MAT, identifying equipment manufacturer to supply microwave equipment, and developing a sophisticated MAT modeling with WPI, the university partner. MAT was shown to enhance calcining through lower energy consumption and faster reaction rates compared to conventional processing. Laboratory testing concluded that a 23% reduction in energy was possible for calcining small batches (5kg). Scale-up testing indicated that the energy savings increased as a function of load size and 36% energy savings was demonstrated (22 kg). A sophisticated model was developed which combines simultaneous microwave and conventional heating. Continued development of this modeling software could be used for larger scale calcining simulations, which would be a beneficial low-cost tool for exploring equipment design prior to actual building. Based on these findings, estimates for production scale MAT calcining benefits were calculated, assuming uptake of MAT in the US lime industry. This estimate showed that 7.3 TBTU/year could be saved, with reduction of 270 MMlbs of CO2 emissions, and $29 MM/year in economic savings. Taking into account estimates for MAT implementation in the US cement industry, an additional 39 TBTU/year, 3 Blbs of CO2 and $155 MM/year could be saved. One of the main remaining barriers to commercialization of MAT for the lime and cement industries is the sheer size of production. Through this project, it was realized that a production size MAT rotary calciner was not feasible, and a different approach was adapted. The concept of a microwave post heat section located in the upper portion of the cooler was devised and appears to be a more realistic approach for MAT implementation. Commercialization of this technology will require (1) continued pilot scale calcining demonstrations, (2) involvement of lime kiln companies, and (3) involvement of an industrial microwave equipment provider. An initial design concept for a MAT post-heat treatment section was conceived as a retrofit into the cooler sections of existing lime rotary calciners with a 1.4 year payback. Retrofitting will help spur implementation of this technology, as the capital investment will be minimal for enhancing the efficiency of current rotary lime kilns. Retrofits would likely be attractive to lime manufacturers, as the purchase of a new lime kiln is on the order of a $30 million dollar investment, where as a MAT retrofit is estimated on the order of $1 million. The path for commercialization lies in partnering with existing lime kiln companies, who will be able to implement the microwave post heat sections in existing and new build kilns. A microwave equipment provider has been identified, who would make up part of the continued development and commercialization team.

  2. Production of a calcium silicate cement material from alginate impression material.

    PubMed

    Washizawa, Norimasa; Narusawa, Hideaki; Tamaki, Yukimichi; Miyazaki, Takashi

    2012-01-01

    The purpose of this study was to synthesize biomaterials from daily dental waste. Since alginate impression material contains silica and calcium salts, we aimed to synthesize calcium silicate cement from alginate impression material. Gypsum-based investment material was also investigated as control. X-ray diffraction analyses revealed that although firing the set gypsum-based and modified investment materials at 1,200°C produced calcium silicates, firing the set alginate impression material did not. However, we succeeded when firing the set blend of pre-fired set alginate impression material and gypsum at 1,200°C. SEM observations of the powder revealed that the featured porous structures of diatomite as an alginate impression material component appeared useful for synthesizing calcium silicates. Experimentally fabricated calcium silicate powder was successfully mixed with phosphoric acid solution and set by depositing the brushite. Therefore, we conclude that the production of calcium silicate cement material is possible from waste alginate impression material. PMID:22864217

  3. Reduced carbon emission estimates from fossil fuel combustion and cement production in China.

    PubMed

    Liu, Zhu; Guan, Dabo; Wei, Wei; Davis, Steven J; Ciais, Philippe; Bai, Jin; Peng, Shushi; Zhang, Qiang; Hubacek, Klaus; Marland, Gregg; Andres, Robert J; Crawford-Brown, Douglas; Lin, Jintai; Zhao, Hongyan; Hong, Chaopeng; Boden, Thomas A; Feng, Kuishuang; Peters, Glen P; Xi, Fengming; Liu, Junguo; Li, Yuan; Zhao, Yu; Zeng, Ning; He, Kebin

    2015-08-20

    Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China's total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China's carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000-2012 than the value reported by China's national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China's cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China's CO2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = ±7.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China's cumulative carbon emissions. Our findings suggest that overestimation of China's emissions in 2000-2013 may be larger than China's estimated total forest sink in 1990-2007 (2.66 gigatonnes of carbon) or China's land carbon sink in 2000-2009 (2.6 gigatonnes of carbon). PMID:26289204

  4. Reduced carbon emission estimates from fossil fuel combustion and cement production in China

    NASA Astrophysics Data System (ADS)

    Liu, Zhu; Guan, Dabo; Wei, Wei; Davis, Steven J.; Ciais, Philippe; Bai, Jin; Peng, Shushi; Zhang, Qiang; Hubacek, Klaus; Marland, Gregg; Andres, Robert J.; Crawford-Brown, Douglas; Lin, Jintai; Zhao, Hongyan; Hong, Chaopeng; Boden, Thomas A.; Feng, Kuishuang; Peters, Glen P.; Xi, Fengming; Liu, Junguo; Li, Yuan; Zhao, Yu; Zeng, Ning; He, Kebin

    2015-08-01

    Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China's total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China's carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000-2012 than the value reported by China's national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China's cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China's CO2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = +/-7.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China's cumulative carbon emissions. Our findings suggest that overestimation of China's emissions in 2000-2013 may be larger than China's estimated total forest sink in 1990-2007 (2.66 gigatonnes of carbon) or China's land carbon sink in 2000-2009 (2.6 gigatonnes of carbon).

  5. Modeling of a self-healing process in blast furnace slag cement exposed to accelerated carbonation

    NASA Astrophysics Data System (ADS)

    Zemskov, Serguey V.; Ahmad, Bilal; Copuroglu, Oguzhan; Vermolen, Fred J.

    2013-02-01

    In the current research, a mathematical model for the post-damage improvement of the carbonated blast furnace slag cement (BFSC) exposed to accelerated carbonation is constructed. The study is embedded within the framework of investigating the effect of using lightweight expanded clay aggregate, which is incorporated into the impregnation of the sodium mono-fluorophosphate (Na-MFP) solution. The model of the self-healing process is built under the assumption that the position of the carbonation front changes in time where the rate of diffusion of Na-MFP into the carbonated cement matrix and the reaction rates of the free phosphate and fluorophosphate with the components of the cement are comparable to the speed of the carbonation front under accelerated carbonation conditions. The model is based on an initial-boundary value problem for a system of partial differential equations which is solved using a Galerkin finite element method. The results obtained are discussed and generalized to a three-dimensional case.

  6. Recent developments in the lime-fly ash process for alumina and cement

    SciTech Connect

    Murtha, M.J.; Burnet, G.

    1981-01-01

    Recent developments from research of the limestone-fly ash sinter process for the extraction of alumina from coal fly ash and use of the residue in the manufacture of portland cement may result in substantial reductions in processing costs. It has been found that cement kiln dust can be used in place of limestone, and that the addition of coal refuse to the sinter mixture will increase alumina recovery and reduce kiln temperatures required. The soluble compound formed in the sintering reactions has been identified through use of XRD methods. Compound formation conditions have been determined for a range of sinter compositions. A systematic investigation of minor additives to sinter compositions has resulted in the determination of a group of ions which, when present in sintered material, will prevent the auto-disintegration (dusting) of the clinker formed. Several ions, even at very low concentrations, can enter the lattice of the major sinter compound, calcium orthosilicate (C/sub 2/S) and inhibit the phase transformation of ..beta..-C/sub 2/S to ..gamma..-C/sub 2/S and the accompanying lattice expansion that causes clinker disintegration. The understanding gained about clinker disintegration, conditions for formation of specific soluble compounds in the clinker, and the roles of coal refuse-derived iron and sulfur in sinter reactions can lead to improvements in the sinter process and enhanced profitability. Use in the process of other wastes provides further incentive for coal ash processing to meet our nation's requirements for alumina and cement, and provide an alternative form of coal combustion waste disposal.

  7. Fjords: Processes and products

    SciTech Connect

    Syvitski, J.P.M.; Burrell, D.C.; Skei, J.M.

    1987-01-01

    Fjords are a major feature of coasts and provide geologists and oceanographers with an excellent environment for studying and modeling coastal processes and products. This book brings together and integrates an enormous amount of information on fjords and provides the reader with a thorough, interdisciplinary account of current research with emphasis on sedimentary processes. The processes demonstrated in fjords are often relevant to the estuarine or open ocean environment.

  8. ALARA Design Review for the Resumption of the Plutonium Finishing Plant (PFP) Cementation Process Project Activities

    SciTech Connect

    DAYLEY, L.

    2000-06-14

    The requirements for the performance of radiological design reviews are codified in 10CFR835, Occupational Radiation Protection. The basic requirements for the performance of ALARA design reviews are presented in the Hanford Site Radiological Control Manual (HSRCM). The HSRCM has established trigger levels requiring radiological reviews of non-routine or complex work activities. These requirements are implemented in site procedures HNF-PRO-1622 and 1623. HNF-PRO-1622 Radiological Design Review Process requires that ''radiological design reviews [be performed] of new facilities and equipment and modifications of existing facilities and equipment''. In addition, HNF-PRO-1623 Radiological Work Planning Process requires a formal ALARA Review for planned activities that are estimated to exceed 1 person-rem total Dose Equivalent (DE). The purpose of this review is to validate that the original design for the PFP Cementation Process ensures that the principles of ALARA (As Low As Reasonably Achievable) were included in the original project design. That is, that the design and operation of existing Cementation Process equipment and processes allows for the minimization of personnel exposure in its operation, maintenance and decommissioning and that the generation of radioactive waste is kept to a minimum.

  9. Borehole cementing over water

    SciTech Connect

    Perkins, T.K.

    1984-05-01

    A borehole cementing process is disclosed in which a quantity of water-like fluid is pumped into a borehole above drilling mud and the cement slurry is pumped into the borehole above at least a portion of the water-like fluid. Turbulent mixing of cement slurry and water at the interface creates an isolation zone preventing degradation of the bulk of the cement slug.

  10. Cement plant CKD recovery system

    SciTech Connect

    Cohen, S.M.; Prokesch, M.E.

    1996-12-31

    A fluid bed system has been developed to produce a low alkali cement clinker from cement plant kiln ducts (CKD). The system is comprised of three main components: feed preparation system, fluid bed reactor and process gas handling system. Cement kiln dust is first pelletized and dried, then processed at 1,300--1,320 C in the fluid bed reactor. The combination of excellent thermal transfer and extended retention time at reaction temperatures provides typical volatilization rates on the order of 90% K{sub 2}O, 70% Na{sub 2}O, 90% SO{sub 3}, and 95% Cl. High concentrations of volatilized alkali compounds in the process off gas stream are cooled and condensed in a specially designed heat exchange system while providing preheated process air for the fluid bed reactor. Condensed alkali compounds are collected at the dust collector in the form of a fine, white powder. This co-product may offer marketable value due to its high concentration of potassium sulfates. The system offers the potential for a 100% recovery of cement kiln dusts to produce cement clinker and an alkali co-product.

  11. The hydration products of Portland cement in the presence of tin(II) chloride

    SciTech Connect

    Hill, J.; Sharp, J.H

    2003-01-01

    The hydration products of Portland cement pastes cured using water containing tin(II) chloride have been compared with those using distilled water. In the latter case, the expected products - portlandite, ettringite and calcite - were observed. The X-ray diffraction patterns of the cement pastes cured in the presence of tin(II) chloride showed several additional peaks that have been attributed to the formation of calcium hydroxo-stannate, CaSn(OH){sub 6}, and Friedel's salt (tetracalcium aluminate dichloride-10-hydrate), Ca{sub 3}Al{sub 2}O{sub 6}{center_dot}CaCl{sub 2}{center_dot}10H{sub 2}O. The amount of portlandite formed was reduced in the presence of tin(II) chloride. Calcium hydroxo-stannate contains tin in the +IV oxidation state and equations are presented to account for the oxidation of Sn(II) to Sn(IV) preceding the formation of CaSn(OH){sub 6} and Friedel's salt.

  12. Cement As a Waste Form for Nuclear Fission Products: The Case of (90)Sr and Its Daughters.

    PubMed

    Dezerald, Lucile; Kohanoff, Jorge J; Correa, Alfredo A; Caro, Alfredo; Pellenq, Roland J-M; Ulm, Franz J; Saúl, Andrés

    2015-11-17

    One of the main challenges faced by the nuclear industry is the long-term confinement of nuclear waste. Because it is inexpensive and easy to manufacture, cement is the material of choice to store large volumes of radioactive materials, in particular the low-level medium-lived fission products. It is therefore of utmost importance to assess the chemical and structural stability of cement containing radioactive species. Here, we use ab initio calculations based on density functional theory (DFT) to study the effects of (90)Sr insertion and decay in C-S-H (calcium-silicate-hydrate) in order to test the ability of cement to trap and hold this radioactive fission product and to investigate the consequences of its ?-decay on the cement paste structure. We show that (90)Sr is stable when it substitutes the Ca(2+) ions in C-S-H, and so is its daughter nucleus (90)Y after ?-decay. Interestingly, (90)Zr, daughter of (90)Y and final product in the decay sequence, is found to be unstable compared to the bulk phase of the element at zero K but stable when compared to the solvated ion in water. Therefore, cement appears as a suitable waste form for (90)Sr storage. PMID:26513644

  13. Addition of mechanically processed cellulosic fibers to ionomer cement: mechanical properties.

    PubMed

    Silva, Rafael Menezes; Carvalho, Vinícius Xavier Mattar de; Dumont, Vitor César; Santos, Maria Helena; Carvalho, Ana Márcia Macedo Ladeira

    2015-01-01

    In this study, conventional restorative glass ionomer cement (GIC) was modified by embedding it with mechanically processed cellulose fibers. Two concentrations of fibers were weighed and agglutinated into the GIC during manipulation, yielding Experimental Groups 2 (G2; 3.62 wt% of fibers) and 3 (G3; 7.24 wt% of fibers), which were compared against a control group containing no fibers (G1). The compressive strengths and elastic modulus of the three groups, and their diametral tensile strengths and stiffness, were evaluated on a universal test machine. The compressive and diametral tensile strengths were significantly higher in G3 than in G1. Statistically significant differences in elastic modulus were also found between G2 and G1 and between G2 and G3, whereas the stiffness significantly differed between G1 and G2. The materials were then characterized by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Heterogeneously shaped particles were found on the G2 and G3 surfaces, and the cement matrices were randomly interspersed with long intermingled fibers. The EDS spectra of the composites revealed the elemental compositions of the precursor materials. The physically processed cellulosic fibers (especially at the higher concentration) increased the compressive and diametral tensile strengths of the GIC, and demonstrated acceptable elastic modulus and stiffness. PMID:25627882

  14. ALARA Design Review for the Resumption of the Plutonium Finishing Plant (PFP) Cementation Process Project Activities

    E-print Network

    Dayley, L

    2000-01-01

    The requirements for the performance of radiological design reviews are codified in 10CFR835, Occupational Radiation Protection. The basic requirements for the performance of ALARA design reviews are presented in the Hanford Site Radiological Control Manual (HSRCM). The HSRCM has established trigger levels requiring radiological reviews of non-routine or complex work activities. These requirements are implemented in site procedures HNF-PRO-1622 and 1623. HNF-PRO-1622 Radiological Design Review Process requires that ''radiological design reviews [be performed] of new facilities and equipment and modifications of existing facilities and equipment''. In addition, HNF-PRO-1623 Radiological Work Planning Process requires a formal ALARA Review for planned activities that are estimated to exceed 1 person-rem total Dose Equivalent (DE). The purpose of this review is to validate that the original design for the PFP Cementation Process ensures that the principles of ALARA (As Low As Reasonably Achievable) were included...

  15. Microstructural and bulk property changes in hardened cement paste during the first drying process

    SciTech Connect

    Maruyama, Ippei; Nishioka, Yukiko; Igarashi, Go; Matsui, Kunio

    2014-04-01

    This paper reports the microstructural changes and resultant bulk physical property changes in hardened cement paste (hcp) during the first desorption process. The microstructural changes and solid-phase changes were evaluated by water vapor sorption, nitrogen sorption, ultrasonic velocity, and {sup 29}Si and {sup 27}Al nuclear magnetic resonance. Strength, Young's modulus, and drying shrinkage were also examined. The first drying process increased the volume of macropores and decreased the volume of mesopores and interlayer spaces. Furthermore, in the first drying process globule clusters were interconnected. During the first desorption, the strength increased for samples cured at 100% to 90% RH, decreased for 90% to 40% RH, and increased again for 40% to 11% RH. This behavior is explained by both microstructural changes in hcp and C–S–H globule densification. The drying shrinkage strains during rapid drying and slow drying were compared and the effects of the microstructural changes and evaporation were separated.

  16. Principles of squeeze cementing

    SciTech Connect

    Goodwin, K.J.

    1984-03-01

    Squeeze cementing is, by historical definition, the application of differential pressure across a cement slurry to accomplish the process of cement dehydration. The primary purpose of the dehydration is to create immobility of the cement slurry until some compressive strength can be developed. Current cementing technology and additives have improved the process sufficiently that the term ''squeeze'' may no longer be applicable. It is felt that ''Remedial Cement Placement'' may be more appropriate, and may more accurately define the process. The success of a remedial cementing operation depends on a finite definition of the existing problem and the results expected from the operation. If the purpose of the squeeze is not definable, a squeeze job may not be necessary. Significant completion dollars are wasted annually on unnecessary squeezes, poorly designed squeeze slurries, and/or improper slurry placement.

  17. Recent technologies and processes for enhanced safety in bitumen or cement solidification of Li/ml radwaste

    SciTech Connect

    Tchemitcheff, F.

    1993-12-31

    SGN has more than 20 years of experience in the treatment of low and medium level radioactive wastes. SGN industrialized two major types of radwaste processes: bituminization and cement solidification. The R&D work on these two processes is discussed.

  18. Utilization of lime-sinter process residue for the manufacture of a low-alumina portland cement

    SciTech Connect

    Chesley, J.A.; Murtha, M.J.; Burnet, G.

    1984-01-01

    The lime-sinter process for recovery of alumina from coal conversion solid wastes produces a residue that is largely dicalcium silicate (C/sub 2/S) and that contains only 3 to 5% Al/sub 2/O/sub 3/. Use of this residue will eliminate the need for its disposal and will make the lime-sinter process more attractive financially. The unique composition of the residue makes it an attractive raw material for the manufacture of ASTM Type V (sulfate resistant) portland cement. There is a substantial demand for this type of cement in the western states. The feasibility of thus using the residue is examined and a cost analysis for a combined alumina-portland cement plant capable of using the fly ash from a 1000 MWe coal-fired power station is presented. 12 references, 1 figure, 6 tables.

  19. Silicon production process evaluations

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Engineering design of the third distillation column in the process was accomplished. The initial design is based on a 94.35% recovery of dichlorosilane in the distillate and a 99.9% recovery of trichlorosilane in the bottoms. The specified separation is achieved at a reflux ratio of 15 with 20 trays (equilibrium stages). Additional specifications and results are reported including equipment size, temperatures and pressure. Specific raw material requirements necessary to produce the silicon in the process are presented. The primary raw materials include metallurgical grade silicon, silicon tetrachloride, hydrogen, copper (catalyst) and lime (waste treatment). Hydrogen chloride is produced as by product in the silicon deposition. Cost analysis of the process was initiated during this reporting period.

  20. Effects of test sample shape and surface production method on the fatigue behaviour of PMMA bone cement.

    PubMed

    Sheafi, E M; Tanner, K E

    2014-01-01

    There is no consensus over the optimal criterion to define the fatigue life of bone cement in vitro. Fatigue testing samples have been made into various shapes using different surface preparation techniques with little attention being paid to the importance of these variations on the fatigue results. The present study focuses on the effect of test sample shape and surface production method on the fatigue results. The samples were manufactured with two cross sectional shapes: rectangular according to ISO 527 and circular according to ASTM F2118. Each shape was produced using two methods: direct moulding of the cement dough and machining from oversized rods. Testing was performed using two different bone cements: SmartSet GHV and DePuy CMW1. At least 10 samples of each category were tested, under fully reversed tension-compression fatigue stress at ±20MPa, to allow for Weibull analysis to compare results. The growth of fatigue cracks was observed by means of the changes in the absorbed energy and apparent modulus. It was found that fatigue crack growth can be altered by the sample shape and production method; however it is also dependent on the chemical composition of the cement. The results revealed that moulded samples, particularly those based on the ASTM F2118 standard, can lead to up to 5.5 times greater fatigue lives compared to the machined samples of the same cement. It is thus essential, when comparing the fatigue results of bone cement, to consider the effect of production method along with the shape of the test sample. PMID:24070780

  1. SEM/EDX characterization of the hydration products of belite cements from class C coal fly ash

    SciTech Connect

    Goni, S.; Guerrero, A.

    2007-12-15

    This paper presents the microscopic characterization of two types of fly ash belite cements and their hydration products by means of scanning electron microscopy, energy-dispersive X-ray microanalysis, and X-ray diffraction analysis. The cements were obtained from ASTM class C coal fly ash by the hydrothermal-calcination route in water (FABC-2-W) and NaOH 1M solution (FABC-2-N). The hydration was studied during a period of 180 days at 21{sup o}C and >95% RH. The results showed significant incorporation of aluminum (Al) into the C-S-H gel and other minor elements, with a presumable composition close to that of aluminum-tobermorite. The C-S-H composition of the FABC-2-W is more stable over the hydration time than that of the FABC-2-N cement. Portlandite is scarcely formed during hydration.

  2. EVALUATION OF PRIMARY AIR VITIATION FOR NITRIC OXIDE REDUCTION IN A ROTARY CEMENT KILN. VOLUME 1. TECHNICAL REPORT

    EPA Science Inventory

    The report gives results of tests to evaluate combustion modifications for nitric oxide (NO) reduction and cement product quality in a pilot-scale long-dry-process cement kiln firing pulverized coal. The kiln is rated at 11.35 kg/s (1080 tons/day) of cement with a thermal input r...

  3. EVALUATION OF PRIMARY AIR VITIATION FOR NITRIC OXIDE REDUCTION IN A ROTARY CEMENT KILN. VOLUME 2. DATA SUPPLEMENT A

    EPA Science Inventory

    The report gives results of tests to evaluate combustion modifications for nitric oxide (NO) reduction and cement product quality in a pilot-scale long-dry-process cement kiln firing pulverized coal. The kiln is rated at 11.35 kg/s (1080 tons/day) of cement with a thermal input r...

  4. Assessment of ferrous chloride and Portland cement for the remediation of chromite ore processing residue.

    PubMed

    Jagupilla, Santhi C; Wazne, Mahmoud; Moon, Deok Hyun

    2015-10-01

    Chromite Ore Processing Residue (COPR) is an industrial waste containing up to 7% chromium (Cr) including up to 5% hexavalent chromium [Cr(VI)]. The remediation of COPR has been challenging due to the slow release of Cr(VI) from a clinker like material and thereby the incomplete detoxification of Cr(VI) by chemical reagents. The use of sulfur based reagents such as ferrous sulfate and calcium polysulfide to detoxify Cr(VI) has exasperated the swell potential of COPR upon treatment. This study investigated the use of ferrous chloride alone and in combination with Portland cement to address the detoxification of Cr(VI) in COPR and the potential swell of COPR. Chromium regulatory tests, X-ray powder diffraction (XRPD) analyses and X-ray absorption near edge structure (XANES) analyses were used to assess the treatment results. The treatment results indicated that Cr(VI) concentrations for the acid pretreated micronized COPR as measured by XANES analyses were below the New Jersey Department of Environmental Protection (NJDEP) standard of 20 mg kg(-1). The Toxicity characteristic leaching procedure (TCLP) Cr concentrations for all acid pretreated samples also were reduced below the TCLP regulatory limit of 5 mg L(-1). Moreover, the TCLP Cr concentration for the acid pretreated COPR with particle size ?0.010 mm were less than the universal treatment standard (UTS) of 0.6 mg L(-1). The treatment appears to have destabilized all COPR potential swell causing minerals. The unconfined compressive strength (UCS) for the treated samples increased significantly upon treatment with Portland cement. PMID:25966327

  5. Performance of lime-soda sinter process residue in the manufacture of sulfate-resistant portland cement

    SciTech Connect

    Chesley, J.A.; Burnet, G.

    1986-04-25

    The residue from the Ames Lime-Soda Sinter Process for recovering alumina from power plant fly ash consists largely of dicalcium silicate and shows promise as a raw material for the manufacture of a low-alumina, sulfate-resistant portland cement. A laboratory burnability study has been conducted to determine the best way to utilize this raw material from both clinker quality and economic perspectives. These tests are essential when a new material, such as the lime-sinter process residue, it to be considered as a possible cement raw material. The amount of unreacted lime can be used as a measure of the reactivity of a raw mix by indicating the extent to which the cement reactions have progressed. Conditions of residence time and temperature used for the burnability tests were chosen to simulate actual kiln operation. A factorial experimental design made of the parameters of burning temperature, lime content, and lumina (flux) content. Preliminary results from this study indicate that a raw mix made from the sinter residue yields a satisfactory cement.

  6. Lunar cement

    NASA Technical Reports Server (NTRS)

    Agosto, William N.

    1992-01-01

    With the exception of water, the major oxide constituents of terrestrial cements are present at all nine lunar sites from which samples have been returned. However, with the exception of relatively rare cristobalite, the lunar oxides are not present as individual phases but are combined in silicates and in mixed oxides. Lime (CaO) is most abundant on the Moon in the plagioclase (CaAl2Si2O8) of highland anorthosites. It may be possible to enrich the lime content of anorthite to levels like those of Portland cement by pyrolyzing it with lunar-derived phosphate. The phosphate consumed in such a reaction can be regenerated by reacting the phosphorus product with lunar augite pyroxenes at elevated temperatures. Other possible sources of lunar phosphate and other oxides are discussed.

  7. Event cementation in sandstones

    SciTech Connect

    Robinson, A. ); Gluyas, J. )

    1991-08-01

    Precipitation of quartz overgrowths on sand grains is a common cause of porosity reduction in sandstones. The amount of quartz overgrowths (cement) often increases with depth so that the process of cementation is generally considered to be a direct response to burial and to proceed throughout the burial history of a sandstone. The authors show that some Mesozoic and Cenozoic sandstones are cemented during events 1-10 m.y. in length, periods one to two orders of magnitude less than their burial histories. Burial alone is unlikely to be the cause of quartz cementation. This new knowledge should markedly change our perception of porosity evolution in sandstones.

  8. Evaluation of Life-Cycle Assessment Studies of Chinese Cement Production: Challenges and Opportunities

    SciTech Connect

    Lu, Hongyou; Masanet, Eric; Price, Lynn

    2009-05-29

    The use of life-cycle assessment (LCA) to understand the embodied energy, environmental impacts, and potential energy-savings of manufactured products has become more widespread among researchers in recent years. This paper reviews recent LCA studies in the cement industry in China and in other countries and provides an assessment of the methodology used by the researchers compared to ISO LCA standards (ISO 14040:2006, ISO 14044:2006, and ISO/TR 14048:2002). We evaluate whether the authors provide information on the intended application, targeted audience, functional unit, system boundary, data sources, data quality assessment, data disaggregation and other elements, and draw conclusions regarding the level of adherence to ISO standards for the papers reviewed. We found that China researchers have gained much experience during last decade, but still have room for improvement in establishing boundaries, assessing data quality, identifying data sources, and explaining limitations. The paper concludes with a discussion of directions for future LCA research in China.

  9. Fan System Optimization Improves Production and Saves Energy at Ash Grove Cement Plant

    SciTech Connect

    2002-05-01

    This case study describes an optimization project implemented on a fan system at Ash Grove Cement Company, which led to annual energy and maintenance savings of $16,000 and 175,000 kilowatt-hours (kWh).

  10. Pore-filling cements in turbidites; Southern California: Products of early diagenesis and dewatering of shale

    NASA Astrophysics Data System (ADS)

    Krystinik, L. F.

    Cementation of deep sea fan deposits which begins at the sediment water interface and continues progressively to the maximum depths was studied. The type and intensity of cementation is determined, in part, by the labile components within the system. Authigenic iron-rich smectite (AIRS) is the earliest cement in deep sea sediment. Formation of AIRS begins with the dissolution of biogenic silica. The Stevens sand provides insight into the early stages of graywacke formation. A significant volume of nondetrital, nonpseudomatrix clay is generated by precipitation of dissolved species carried into a sandstone body by waters expelled from adjacent shale. The Stevens also provides insight into turbidite sedimentation within a restricted basin supplied by several sediment sources. Most Cenozoic turbidities from southern California contain either calcite cement which occludes porosity and preserves the initial character of the sediment, or a silica clay cement which reduces porosity slightly, but occludes permeability. Cementation of sandstones by clays precipitated from pore fluids generated in adjacent shales may be a first step toward the genesis of graywacke.

  11. Comparison of modified sulfur cement and hydraulic cement for encapsulation of radioactive and mixed wastes

    SciTech Connect

    Kalb, P.D.; Heiser, J.H. III; Colombo, P.

    1990-01-01

    The majority of solidification/stabilization systems for low-level radioactive waste (LLW) and mixed waste, both in the commercial sector and at Department of Energy (DOE) facilities, utilize hydraulic cement (such as portland cement) to encapsulate waste materials and yield a monolithic solid waste form for disposal. A new and innovative process utilizing modified sulfur cement developed by the US Bureau of Mines has been applied at Brookhaven National Laboratory (BNL) for the encapsulation of many of these problem'' wastes. Modified sulfur cement is a thermoplastic material, and as such, it can be heated above it's melting point (120{degree}C), combined with dry waste products to form a homogeneous mixture, and cooled to form a monolithic solid product. Under sponsorship of the DOE, research and development efforts at BNL have successfully applied the modified sulfur cement process for treatment of a range of LLWs including sodium sulfate salts, boric acid salts, and incinerator bottom ash and for mixed waste contaminated incinerator fly ash. Process development studies were conducted to determine optimal waste loadings for each waste type. Property evaluation studies were conducted to test waste form behavior under disposal conditions by applying relevant performance testing criteria established by the Nuclear Regulatory Commission (for LLW) and the Environmental Protection Agency (for hazardous wastes). Based on both processing and performance considerations, significantly greater waste loadings were achieved using modified sulfur cement when compared with hydraulic cement. Technology demonstration of the modified sulfur cement encapsulation system using production-scale equipment is scheduled for FY 1991. 12 refs., 8 figs., 3 tabs.

  12. Utilization of municipal solid waste incineration fly ash for sulfoaluminate cement clinker production

    SciTech Connect

    Wu Kai; Shi Huisheng; Guo Xiaolu

    2011-09-15

    Highlights: > The replacement can be taken up to 30% of MSWI fly ash in the raw mix. > The novelty compositional parameters were defined, their optimum values were determined. > Expansive property of SAC is strongly depended on gypsum content. > Three leaching test methods are used to assess the environmental impact. - Abstract: The feasibility of partially substituting raw materials with municipal solid waste incineration (MSWI) fly ash in sulfoaluminate cement (SAC) clinker production was investigated by X-ray diffraction (XRD), compressive strength and free expansion ratio testing. Three different leaching tests were used to assess the environmental impact of the produced material. Experimental results show that the replacement of MSWI fly ash could be taken up to 30% in the raw mixes. The good quality SAC clinkers are obtained by controlling the compositional parameters at alkalinity modulus (C{sub m}) around 1.05, alumina-sulfur ratio (P) around 2.5, alumina-silica ratio (N) around 2.0{approx}3.0 and firing the raw mixes at 1250 deg. C for 2 h. The compressive strengths of SAC are high in early age while that develop slowly in later age. Results also show that the expansive properties of SAC are strongly depended on the gypsum content. Leaching studies of toxic elements in the hydrated SAC-based system reveal that all the investigated elements are well bounded in the clinker minerals or immobilized by the hydration products. Although some limited positive results indicate that the SAC prepared from MSWI fly ash would present no immediate thread to the environment, the long-term toxicity leaching behavior needs to be further studied.

  13. The processing, mechanical properties and bioactivity of strontium based glass polyalkenoate cements.

    PubMed

    Wren, Anthony; Boyd, Daniel; Towler, M R

    2008-04-01

    The suitability of zinc-based glass polyalkenoate cements (GPCs) for use in orthopaedics can be improved by the substitution of strontium into the glass phase which should impart improved radiopacity and bone forming properties to the cements without retarding strength. The purpose of this research was to produce novel GPCs based on calcium-strontium-zinc-silicate glasses and to evaluate their mechanical properties and biocompatibility with the ultimate objective of developing a new range of cements for skeletal applications. Three glass compositions, based on incremental substitutions of strontium for calcium, were synthesized; BT100 (0.16CaO, 0.36ZnO, 0.48SiO2), BT101 (0.04SrO, 0.12CaO, 0.36ZnO, 0.48SiO2) and BT102 (0.08SrO 0.08CaO, 0.36ZnO, 0.48SiO2). Each glass was then mixed with varying concentrations and molecular weights of polyacrylic acids in order to determine the working times, setting times, compressive strengths and biaxial flexural strengths of the novel cements. The maximum working time and setting time achieved was 29 and 110 s respectively; which, at present is inadequate for current clinical procedures. However, the optimum compressive and biaxial flexural strengths were up to 75 and 34 MPa respectively indicating that these formulations have potential in load bearing applications. Importantly, the substitution of Ca with Sr in the glasses did not have a deleterious effect on strengths or working times. Finally, the bioactivity of the best performing cements was determined in vitro using simulated body fluid. It was found that all cements facilitate the formation of an amorphous calcium phosphate at their surface which increases in density and coverage with time, indicating that these cement will bond directly to bone in vivo. PMID:17943414

  14. Reducing cement's CO2 footprint

    USGS Publications Warehouse

    van Oss, Hendrik G.

    2011-01-01

    The manufacturing process for Portland cement causes high levels of greenhouse gas emissions. However, environmental impacts can be reduced by using more energy-efficient kilns and replacing fossil energy with alternative fuels. Although carbon capture and new cements with less CO2 emission are still in the experimental phase, all these innovations can help develop a cleaner cement industry.

  15. High temperature lightweight foamed cements

    DOEpatents

    Sugama, Toshifumi.

    1989-10-03

    Cement slurries are disclosed which are suitable for use in geothermal wells since they can withstand high temperatures and high pressures. The formulation consists of cement, silica flour, water, a retarder, a foaming agent, a foam stabilizer, and a reinforcing agent. A process for producing these cements is also disclosed. 3 figs.

  16. High temperature lightweight foamed cements

    DOEpatents

    Sugama, Toshifumi (Mastic Beach, NY)

    1989-01-01

    Cement slurries are disclosed which are suitable for use in geothermal wells since they can withstand high temperatures and high pressures. The formulation consists of cement, silica flour, water, a retarder, a foaming agent, a foam stabilizer, and a reinforcing agent. A process for producing these cements is also disclosed.

  17. Silicon production process evaluations

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The chemical engineering analysis of the preliminary process design of a process for producing solar cell grade silicon from dichlorosilane is presented. A plant to produce 1,000 MT/yr of silicon is analyzed. Progress and status for the plant design are reported for the primary activities of base case conditions (60 percent), reaction chemistry (50 percent), process flow diagram (35 percent), energy balance (10 percent), property data (10 percent) and equipment design (5 percent).

  18. The use of electrical impedance spectroscopy for monitoring the hydration products of Portland cement mortars with high percentage of pozzolans

    SciTech Connect

    Cruz, J.M.; Fita, I.C.; Soriano, L.; Payá, J.; Borrachero, M.V.

    2013-08-15

    In this paper, mortars and pastes containing large replacement of pozzolan were studied by mechanical strength, thermogravimetric analysis (TGA), scanning electronic microscopy (SEM), mercury intrusion porosimetry (MIP) and electrical impedance spectroscopy (EIS). The effect of metakaolin (35%) and fly ash (60%) was evaluated and compared with an inert mineral addition (andalusite). The portlandite content was measured, finding that the pozzolanic reaction produced cementing systems with all portlandite fixed. The EIS measurements were analyzed by the equivalent electrical circuit (EEC) method. An EEC with three branches in parallel was applied. The dc resistance was related to the degree of hydration and allowed us to characterize plain and blended mortars. A constant phase element (CPE) quantified the electrical properties of the hydration products located in the solid–solution interface and was useful to distinguish the role of inert and pozzolanic admixtures present in the cement matrix.

  19. Copper-promoted cementation of antimony in hydrochloric acid system: A green protocol.

    PubMed

    Wu, Lian-Kui; Li, Ying-Ying; Cao, Hua-Zhen; Zheng, Guo-Qu

    2015-12-15

    A new method of recovering antimony in hydrochloric acid system by cementation with copper powder was proposed and carried out at laboratory scale. Thermodynamic analysis and cyclic voltammetry test were conducted to study the cementation process. This is a novel antimony removal technology and quite meets the requirements of green chemistry. The main cement product Cu2Sb is a promising anodic material for lithium and sodium ion battery. And nearly all consumed copper powder are transformed into CuCl which is an important industrial material. The effect of reaction temperature, stoichiometric ratio of Cu to Sb(III), stirring rate and concentration of HCl on the cementation efficiency of antimony were investigated in detail. Optimized cementation condition is obtained at 60°C for 120min and stirring rate of 600rpm with Cu/Sb(III) stoichiometric ratio of 6 in 3molL(-1) HCl. At this time, nearly all antimony can be removed by copper powder and the cementation efficiency is over 99%. The structure and morphologies of the cement products were characterized by X-ray diffraction and scanning electron microscopy, respectively. Results show that the reaction temperature has little influence on the morphology of the cement products which consist of particles with various sizes. The activation energy of the cementation antimony on copper is 37.75kJmol(-1), indicating a chemically controlled step. Inductively coupled plasma mass spectrometry results show that no stibine generates during the cementation process. PMID:26252996

  20. NASA Product Peer Review Process

    NASA Technical Reports Server (NTRS)

    Jenks, Ken

    2009-01-01

    This viewgraph presentation describes NASA's product peer review process. The contents include: 1) Inspection/Peer Review at NASA; 2) Reasons for product peer reviews; 3) Different types of peer reviews; and 4) NASA requirements for peer reviews. This presentation also includes a demonstration of an actual product peer review.

  1. The Product Development Process.

    ERIC Educational Resources Information Center

    Bowman, Harry L.

    Product development has emerged very recently as an area of specialization within the field of education, having received its greatest impetus with the establishment of the federally funded educational research and development centers in 1964 and the regional educational laboratories in 1965. The first part of this three-part document defines…

  2. Asphalt cement

    MedlinePLUS

    ... petroleum material that hardens when it cools. Asphalt cement poisoning occurs when someone swallows asphalt. This is ... Road paving materials Roofing materials Tile cements Note: This list may not include all uses of asphalt.

  3. Metallic aluminum in MSWI fly ash: quantification and influence on the properties of cement-based products.

    PubMed

    Aubert, J E; Husson, B; Vaquier, A

    2004-01-01

    This article focuses on the effects of metallic aluminum contained in municipal solid waste incineration (MSWI) fly ashes on cement-based materials in which they are added. The ash under study was treated by an industrial physicochemical process of neutralization. The paper also presents a method to quantify the metallic aluminum content of ash: it consists in measuring the amount of hydrogen gas produced by the oxidation reaction of metallic aluminum. This method is simple and fast. Results show that studied ash contains an appreciable amount of metallic aluminum. Investigations were carried out to study the incorporation of the ash in concrete: in this case, the presence of metallic aluminum is worrying because it could be responsible for disorders in concrete. In fact, swellings are observed on cement pastes and mortars containing ash during the first 24 h of hydration. A test based on hydrostatic weighing permits to quantify the swelling of fresh cement paste and to study the evolution of this swelling. Causes of swelling are analyzed. Results show that ettringite formation occurs after the end of the expansion reaction. So it can be concluded that metallic aluminum is the sole responsible for the observed swelling. Consequences of swelling are also analyzed by measuring compressive strength of ash-containing mortars: this swelling leads to cracks in the mortars and significant decrease of their compressive strength. PMID:15219917

  4. Cement-based electronics

    NASA Astrophysics Data System (ADS)

    Konesky, Gregory A.

    2004-03-01

    The term Intelligent Highway is usually intended to mean external systems that are added to pre-existing highways. However, the ability to construct basic passive electronic elements is demonstrated employing electrically dissimilar Portland cement pastes. These electronic elements include resistors, rectifying pn-junctions, piezoelectric and piezoresistive sensors, and thermocouple junctions. It may therefore be possible to build intelligence into the highway itself utilizing cement-based electronic devices. As compared to semiconductor-based electronic components, those derived from cement have minimal materials and processing costs, do not require clean rooms, and are mechanically more rugged. Results and characterizations are presented for resistive elements and rectifying pn-junctions derived from admixtures of stainless steel fiber (n-type) and carbon fiber (p-type) in Portland cement. These elements are then combined to produce a monolithic cement-based digital logic 2-input AND gate.

  5. International Best Practices for Pre-Processing and Co-Processing Municipal Solid Waste and Sewage Sludge in the Cement Industry

    SciTech Connect

    Hasanbeigi, Ali; Lu, Hongyou; Williams, Christopher; Price, Lynn

    2012-07-01

    The purpose of this report is to describe international best practices for pre-processing and coprocessing of MSW and sewage sludge in cement plants, for the benefit of countries that wish to develop co-processing capacity. The report is divided into three main sections. Section 2 describes the fundamentals of co-processing, Section 3 describes exemplary international regulatory and institutional frameworks for co-processing, and Section 4 describes international best practices related to the technological aspects of co-processing.

  6. Recovery Act Production of Algal BioCrude Oil from Cement Plant Carbon Dioxide

    SciTech Connect

    Robert Weber; Norman Whitton

    2010-09-30

    The consortium, led by Sunrise Ridge Algae Inc, completed financial, legal, siting, engineering and environmental permitting preparations for a proposed demonstration project that would capture stack gas from an operating cement plant and convert the carbon dioxide to beneficial use as a liquid crude petroleum substitute and a coal substitute, using algae grown in a closed system, then harvested and converted using catalyzed pyrolysis.

  7. Opportunities for Energy Efficiency and Demand Response in the California Cement Industry

    SciTech Connect

    Olsen, Daniel; Goli, Sasank; Faulkner, David; McKane, Aimee

    2010-12-22

    This study examines the characteristics of cement plants and their ability to shed or shift load to participate in demand response (DR). Relevant factors investigated include the various equipment and processes used to make cement, the operational limitations cement plants are subject to, and the quantities and sources of energy used in the cement-making process. Opportunities for energy efficiency improvements are also reviewed. The results suggest that cement plants are good candidates for DR participation. The cement industry consumes over 400 trillion Btu of energy annually in the United States, and consumes over 150 MW of electricity in California alone. The chemical reactions required to make cement occur only in the cement kiln, and intermediate products are routinely stored between processing stages without negative effects. Cement plants also operate continuously for months at a time between shutdowns, allowing flexibility in operational scheduling. In addition, several examples of cement plants altering their electricity consumption based on utility incentives are discussed. Further study is needed to determine the practical potential for automated demand response (Auto-DR) and to investigate the magnitude and shape of achievable sheds and shifts.

  8. Products and Processes: Synergistic Relationships

    ERIC Educational Resources Information Center

    Wallace, Virginia; Husid, Whitney

    2013-01-01

    Most people agree that products are the culmination of what students have studied. For this article, "product" will refer to students' abilities to create outcomes and design artifacts. Those abilities are guided by four processes: inquiry-based learning, use of a research model, use of Web 2.0 tools, and appropriate assessments.…

  9. Energy Efficiency Improvement Opportunities for the Cement Industry

    SciTech Connect

    Price, Lynn; Worrell, Ernst; Galitsky, Christina; Price, Lynn

    2008-01-31

    This report provides information on the energy savings, costs, and carbon dioxide emissions reductions associated with implementation of a number of technologies and measures applicable to the cement industry. The technologies and measures include both state-of-the-art measures that are currently in use in cement enterprises worldwide as well as advanced measures that are either only in limited use or are near commercialization. This report focuses mainly on retrofit measures using commercially available technologies, but many of these technologies are applicable for new plants as well. Where possible, for each technology or measure, costs and energy savings per tonne of cement produced are estimated and then carbon dioxide emissions reductions are calculated based on the fuels used at the process step to which the technology or measure is applied. The analysis of cement kiln energy-efficiency opportunities is divided into technologies and measures that are applicable to the different stages of production and various kiln types used in China: raw materials (and fuel) preparation; clinker making (applicable to all kilns, rotary kilns only, vertical shaft kilns only); and finish grinding; as well as plant wide measures and product and feedstock changes that will reduce energy consumption for clinker making. Table 1 lists all measures in this report by process to which they apply, including plant wide measures and product or feedstock changes. Tables 2 through 8 provide the following information for each technology: fuel and electricity savings per tonne of cement; annual operating and capital costs per tonne of cement or estimated payback period; and, carbon dioxide emissions reductions for each measure applied to the production of cement. This information was originally collected for a report on the U.S. cement industry (Worrell and Galitsky, 2004) and a report on opportunities for China's cement kilns (Price and Galitsky, in press). The information provided in this report is based on publicly-available reports, journal articles, and case studies from applications of technologies around the world.

  10. Performance of Concrete Made With Slag Cement and

    E-print Network

    Performance of Concrete Made With Slag Cement and Portland-Limestone Blended Cement Philadelphia;Today's Discussion ! The materials ! Slag cement ! Portland-limestone cement ! Use in concrete is slag cement? #12;! Non-metallic product of an iron blast furnace ! Granulated ! Ground ! Cementitious

  11. Product List Substructure -Foundations -Slab on Grade

    E-print Network

    Lafarge Silica Fume Cement Anonymous IP Cement Product Lafarge NewCem Slag Cement (20%) Lafarge NewCem Slag Cement (35%) Lafarge NewCem Slag Cement (50%) Generic 35% Fly Ash Cement Lafarge Portland Type I Lafarge Silica Fume Cement Anonymous IP Cement Product Lafarge NewCem Slag Cement (20 %) Lafarge New

  12. Energy savings by improved control of the finish grinding process in cement manufacture: Final report, January 1, 1985-December 31, 1986

    SciTech Connect

    Weiss, S.J.; Tresouthick, S.W.

    1987-03-01

    Conventional closed-circuit ball mill systems for the finish grinding of portland cement produces product particle size distributions (PSDs) which indicate poor reduction of topsize and excessive production of fines. Optimization of ball mill systems should improve energy efficiency while meeting or exceeding typical cement performance requirements. Pilot scale continuous grinding systems, including a closed-circuit ball mill with a conventional classifier, a high-efficiency classifier, or a vertical roller mill were used to determine operating conditions and configurations which would lead to narrowing of the cement PSD. Closed-circuit ball mill results suggest that several opportunities exist to increase particle breakage efficiencies while minimizing unnecessary fines generation by means such as: modification of mill recirculation rates, optimal selection of ball size distribution, and use of highly efficient particle size classifiers. Mill system design philosophies common worldwide which favor long mill lengths, fine ball charges, and low circulating loads are called into question. In order to produce cements with acceptable early mortar strengths by sole use of a roller mill, products must be ground to finenesses similar to those of conventional cements.

  13. Predicting the Impact of Multiwalled Carbon Nanotubes on the Cement Hydration Products and Durability of Cementitious Matrix Using Artificial Neural Network Modeling Technique

    PubMed Central

    Fakhim, Babak; Hassani, Abolfazl; Rashidi, Alimorad; Ghodousi, Parviz

    2013-01-01

    In this study the feasibility of using the artificial neural networks modeling in predicting the effect of MWCNT on amount of cement hydration products and improving the quality of cement hydration products microstructures of cement paste was investigated. To determine the amount of cement hydration products thermogravimetric analysis was used. Two critical parameters of TGA test are PHPloss and CHloss. In order to model the TGA test results, the ANN modeling was performed on these parameters separately. In this study, 60% of data are used for model calibration and the remaining 40% are used for model verification. Based on the highest efficiency coefficient and the lowest root mean square error, the best ANN model was chosen. The results of TGA test implied that the cement hydration is enhanced in the presence of the optimum percentage (0.3?wt%) of MWCNT. Moreover, since the efficiency coefficient of the modeling results of CH and PHP loss in both the calibration and verification stages was more than 0.96, it was concluded that the ANN could be used as an accurate tool for modeling the TGA results. Another finding of this study was that the ANN prediction in higher ages was more precise. PMID:24489487

  14. Environmentally compatible spray cement

    SciTech Connect

    Loeschnig, P.

    1995-12-31

    Within the framework of a European research project, Heidelberger Zement developed a quickly setting and hardening binder for shotcrete, called Chronolith S, which avoids the application of setting accelerators. Density and strength of the shotcrete produced with this spray cement correspond to those of an unaccelerated shotcrete. An increased hazard for the heading team and for the environment, which may occur when applying setting accelerators, can be excluded here. Owing to the special setting properties of a spray cement, the process engineering for its manufacturing is of great importance. The treatment of a spray cement as a dry concrete with kiln-dried aggregates is possible without any problems. The use of a naturally damp pre-batched mixture is possible with Chronolith S but requires special process engineering; spray cement and damp aggregate are mixed with one another immediately before entering the spraying machinery.

  15. Process Flow Chart for Immobilizing of Radioactive High Concentration Sodium Hydroxide Product from the Sodium Processing Facility at the BN-350 Nuclear power plant in Aktau, Kazakhstan

    SciTech Connect

    Burkitbayev, M.; Omarova, K.; Tolebayev, T.; Galkin, A.; Bachilova, N.; Blynskiy, A.; Maev, V.; Wells, D.; Herrick, A.; Michelbacher, J.

    2008-07-01

    This paper describes the results of a joint research investigations carried out by the group of Kazakhstan, British and American specialists in development of a new material for immobilization of radioactive 35% sodium hydroxide solutions from the sodium coolant processing facility of the BN-350 nuclear power plant. The resulting solid matrix product, termed geo-cement stone, is capable of isolating long lived radionuclides from the environment. The physico-mechanical properties of geo-cement stone have been investigated and the flow chart for its production verified in a full scale experiments. (author)

  16. The FGM Concept in the Development of Fiber Cement Components

    SciTech Connect

    Dias, C. M. R.; John, V. M.; Savastano, H. Jr.

    2008-02-15

    The FGM concept appears promising in improving the mechanical performance and reducing production costs of fiber cement building components. However, it has not yet been broadly applied to fiber cement technology. In this study we analyze the functionally graded fiber cement concept and its potential for industrial application in Hatschek machines. The conventional Hatschek process is summarized as well as the proposed modifications to allow FGM fiber cement production. The feasibility of producing functionally graded fiber cement by grading PVA fiber content was experimentally evaluated. Thermogravimetric (TG) and Scanning Electron Microscope (SEM) analysis were used to evaluate fiber distribution profiles. Four-point bending tests were applied to evaluate the mechanical performance of both conventional and functionally graded composites. The results shows that grading PVA fiber content is an effective way to produce functionally graded fiber cement, allowing the reduction of the total fiber volume without significant reduction on composite MOR. TG tests were found adequate to assess fiber content at different positions in functionally graded fiber cements.

  17. Thermodynamics and cement science

    SciTech Connect

    Damidot, D.; Lothenbach, B.; Herfort, D.; Glasser, F.P.

    2011-07-15

    Thermodynamics applied to cement science has proved to be very valuable. One of the most striking findings has been the extent to which the hydrate phases, with one conspicuous exception, achieve equilibrium. The important exception is the persistence of amorphous C-S-H which is metastable with respect to crystalline calcium silicate hydrates. Nevertheless C-S-H can be included in the scope of calculations. As a consequence, from comparison of calculation and experiment, it appears that kinetics is not necessarily an insuperable barrier to engineering the phase composition of a hydrated Portland cement. Also the sensitivity of the mineralogy of the AFm and AFt phase compositions to the presence of calcite and to temperature has been reported. This knowledge gives a powerful incentive to develop links between the mineralogy and engineering properties of hydrated cement paste and, of course, anticipates improvements in its performance leading to decreasing the environmental impacts of cement production.

  18. Discovery Reconceived: Product before Process

    ERIC Educational Resources Information Center

    Abrahamson, Dor

    2012-01-01

    Motivated by the question, "What exactly about a mathematical concept should students discover, when they study it via discovery learning?", I present and demonstrate an interpretation of discovery pedagogy that attempts to address its criticism. My approach hinges on decoupling the solution process from its resultant product. Whereas theories of…

  19. Revised 08-2014 TASK FORCE ARTICLES OF AGREEMENT FOR PORTLAND CEMENT

    E-print Network

    Revised 08-2014 TASK FORCE ARTICLES OF AGREEMENT FOR PORTLAND CEMENT AND BLENDED CEMENTS CEMENT OF CEMENT COMPANY: FACILITY LOCATED AT CEMENT TYPE & ASSOCIATED PRODUCT NAME 1. The host state agency that performs testing for acceptance of hydraulic cement plants within its boundaries shall have a laboratory

  20. Utilization of industrial waste products as pozzolanic material in cemented paste backfill of high sulphide mill tailings.

    PubMed

    Ercikdi, Bayram; Cihangir, Ferdi; Kesimal, Ayhan; Deveci, Haci; Alp, Ibrahim

    2009-09-15

    In this study, the potential use of the industrial waste products including waste glass (WG), fly ash (FA), granulated blast furnace slag (GBFS) and silica fume (SF) as pozzolanic additive for the partial replacement of ordinary Portland cement (OPC) in cemented paste backfill (CPB) of sulphide-rich mill tailings was investigated. The influence of these industrial waste products on the short- and long-term mechanical performance of CPB was demonstrated. The rate of development of strength of CPB samples tended to slow down when the pozzolanic wastes were incorporated or increased in dosage in the binder phase. Severe losses (by 26%) in the strength of CPB samples produced from exclusively OPC occurred after an initial curing period of 56 days. The addition of WG (10-30 wt%) as a partial replacement of OPC was observed to aggravate further the strength losses of CPB samples. GBFS, FA and SF appeared to improve the long-term performance of CPB samples; albeit, only GBFS and SF could be incorporated into the binder phase only at certain levels i.e. up to 20 wt% GBFS and 15wt% SF in order to maintain a threshold strength level of 0.7MPa over 360 days. SEM studies have provided further insight into the microstucture of CPB and confirmed the formation of deleterious gypsum as the expansive phase. These findings have demonstrated that the industrial waste products including GBFS and SF can be suitably used as mineral additives to improve the long-term mechanical performance of CPB produced from sulphide-rich tailings as well as to reduce the binder costs in a CPB plant. PMID:19299080

  1. Modern production process for magnesium

    SciTech Connect

    Wilson, C.B.

    1996-10-01

    There are currently two major routes practiced industrially for the production of primary magnesium metal. The first of these is the electrolysis of magnesium chloride and the second is the thermal reduction of magnesium oxide. Within these two major categories, there are many variations of the technologies in the industry. The dominant production method is the electrolysis of magnesium chloride and this is carried out by The Dow Chemical Company, Norsk Hydro, Magcorp, and the plants in the Former Soviet Union. Each of the processes at these facilities uses a different means of feed preparation and this in turn causes the electrolytic cell end of the processes to be different also. The second technology is the thermal reduction of magnesium oxide, and there are at least three different variations which are practiced industrially. The first of these is the Pidgeon process which reacts dolime (MgO{center_dot}CaO) with ferro-silicon (FeSi) to form a di-calcium silicate and magnesium metal at an elevated (about 1,200 C) temperature and reduced pressure in an externally heated retort. Timminco uses this process to produce a very high purity magnesium. The second process reacts the same starting raw materials at similar (about 1,250 C) temperatures in an internally heated reactor under reduced pressure. This is done by Brasmag in Brazil. The final variation of the ferro-silicon process is the Magnetherm{reg_sign} process developed by Pechiney and practiced by pechiney and Alcoa. This system uses slag resistance heating and very high (about 1,550 C) temperatures. This paper will examine each of these production methods and discuss both their merits and their weaknesses.

  2. Research of magnesium phosphosilicate cement

    NASA Astrophysics Data System (ADS)

    Ding, Zhu

    Magnesium phosphosilicate cement (MPSC) is a novel phosphate bonded cement, which consists mainly of magnesia, phosphate and silicate minerals. The traditional magnesium phosphate cements (MPCs) usually composed by ammonium phosphate, and gaseous ammonia will emit during mixing and in service. There is no noxious ammonia released from MPSC, furthermore, it can recycle a large volume of the non-hazardous waste. The goal of this research is to investigate the composition, reaction products, reaction mechanism, microstructure, properties, durability and applications of the MPSC. MPSC sets rapidly and has high early strength. It reacts better with solid industrial waste when compared to Portland cement. Many solid industrial wastes, such as fly ash, steel slag, coal gangue, red coal gangue, red mud, barium-bearing slag, copper slag, silica fume, and ground granulated blast furnace slag, have been used as the main component (40% by weight) in MPSC. The research has found that these aluminosilicate (or ironsilicate, or calciumsilicate) minerals with an amorphous or glass structure can enhance the performance of MPSC. The disorganized internal structure of amorphous materials may make it possess higher reactivity compared to the crystalline phases. Chemical reaction between phosphate and these minerals may form an amorphous gel, which is favorable to the cementing. Borax, boric acid and sodium tripolyphosphate have been used as retardants in the MPSC system. It is found that boric acid has a higher retarding effect on the setting of cement, than borax does. However, sodium polyphosphate accelerates the reaction of MPSC. The hydration of MPSC is exothermic reaction. The heat evolution may prompt hydrates formation, and shorten the setting process. Modern materials characterization techniques, XRD, DSC, TG-DTA FTIR, XPS, MAS-NMR, SEM, TEM, MIP, etc. were used to analyze the phase composition, micro morphology, and microstructure of hardened MPSC. The main hydration product in MPSC is MgKPO4·6H2O (MKP), which has both crystalline and amorphous phases. There are many unreacted magnesia grains in the hardened MPSC paste. They act as nucleus of the hardened framework. The hydrates grow around the magnesia grains rims, fill in the voids among the magnesia grains and bond unreacted magnesia part into a solid continuum. (Abstract shortened by UMI.)

  3. Thermal Shock-resistant Cement

    SciTech Connect

    Sugama T.; Pyatina, T.; Gill, S.

    2012-02-01

    We studied the effectiveness of sodium silicate-activated Class F fly ash in improving the thermal shock resistance and in extending the onset of hydration of Secar #80 refractory cement. When the dry mix cement, consisting of Secar #80, Class F fly ash, and sodium silicate, came in contact with water, NaOH derived from the dissolution of sodium silicate preferentially reacted with Class F fly ash, rather than the #80, to dissociate silicate anions from Class F fly ash. Then, these dissociated silicate ions delayed significantly the hydration of #80 possessing a rapid setting behavior. We undertook a multiple heating -water cooling quenching-cycle test to evaluate the cement’s resistance to thermal shock. In one cycle, we heated the 200 and #61616;C-autoclaved cement at 500 and #61616;C for 24 hours, and then the heated cement was rapidly immersed in water at 25 and #61616;C. This cycle was repeated five times. The phase composition of the autoclaved #80/Class F fly ash blend cements comprised four crystalline hydration products, boehmite, katoite, hydrogrossular, and hydroxysodalite, responsible for strengthening cement. After a test of 5-cycle heat-water quenching, we observed three crystalline phase-transformations in this autoclaved cement: boehmite and #61614; and #61543;-Al2O3, katoite and #61614; calcite, and hydroxysodalite and #61614; carbonated sodalite. Among those, the hydroxysodalite and #61614; carbonated sodalite transformation not only played a pivotal role in densifying the cementitious structure and in sustaining the original compressive strength developed after autoclaving, but also offered an improved resistance of the #80 cement to thermal shock. In contrast, autoclaved Class G well cement with and without Class F fly ash and quartz flour failed this cycle test, generating multiple cracks in the cement. The major reason for such impairment was the hydration of lime derived from the dehydroxylation of portlandite formed in the autoclaved cement, causing its volume to expand.

  4. Climate change: The impact of the third conference of the parties at Kyoto on the U.S. Portland cement industry

    SciTech Connect

    Cahn, D.; Nisbet, M.; O`Hare, A.

    1998-12-31

    The paper provides, as background, a brief review of the structure of the US cement industry. It outlines the growth trends of the industry over the last 20 years. It describes the sources and significance of cement imports in the US market, and the importance of exports to Canadian cement producers. The sources of CO{sub 2}, the primary greenhouse gas emitted in the cement manufacturing process, are explained and the impact of improved energy efficiency and fuel switching on CO{sub 2} emissions per ton of product are discussed. The aspects of the Kyoto Protocol relevant to the US cement industry are analyzed as are the types of impacts they can be expected to have on: cement trade, domestic cement production, long term growth of the US cement industry, and US cement industry CO{sub 2} emissions. The paper projects the US cement industry CO{sub 2} emissions to 2010, taking into account anticipated improvements in energy efficiency. It discusses manufacturing process and changes that could be made to reduce CO{sub 2} emissions. The paper also covers the types of product modifications that might be made to reduce the embodied CO{sub 2} content. Where possible the potential reductions in CO{sub 2} emissions from process and product changes are quantified.

  5. Fluid loss control in oil field cements

    SciTech Connect

    Newlove, J. C.; Kitano, K.; Portnoy, R. C.; Schulz, D. N.

    1984-11-06

    The present invention relates to materials which reduce the filtration of fluid into permeable earth formations during cementing processes in the drilling and completing of subterranean wells, particularly wells for the recovery of petroleum resources. Petroleum well cementing is the process of mixing a slurry of cement, water, and other additives and pumping it down through steel casing to critical points in the oil well annulus around the casing or in the open hole below the casing string. The primary functions of the cementing process are to restrict fluid movement between geological formations and to bond and support the casing. In addition the cement aids in protecting the casing from corrosion, preventing blowouts by quickly sealing formations, protecting the casing from shock loads in drilling deeper wells, and sealing off lost circulation or thief zones. A common problem in petroleum well cementing is the flow of liquid from the cement slurry into porous earth formations in contact with the cement. This fluid loss is undesirable since it can result in dehydration of the cement slurry, and it causes thick filter cakes of cement solids which can plug the well bore. The fluid lost can damage sensitive formations. Cement fluid loss is particularly a problem in the process known as squeeze cementing. There is a requirement, therefore, for materials which, when added to the cement formulation, reduce the loss of fluid from the slurry to porous formations.

  6. Synthesis: Intertwining product and process

    NASA Technical Reports Server (NTRS)

    Weiss, David M.

    1990-01-01

    Synthesis is a proposed systematic process for rapidly creating different members of a program family. Family members are described by variations in their requirements. Requirements variations are mapped to variations on a standard design to generate production quality code and documentation. The approach is made feasible by using principles underlying design for change. Synthesis incorporates ideas from rapid prototyping, application generators, and domain analysis. The goals of Synthesis and the Synthesis process are discussed. The technology needed and the feasibility of the approach are also briefly discussed. The status of current efforts to implement Synthesis methodologies is presented.

  7. Automation of IRFPA production processes

    NASA Astrophysics Data System (ADS)

    Egerton, J.; Dieselman, N.; Higgins, W.; Zimmermann, P.; Sood, A.

    1990-11-01

    This paper examines three applications of automation technology in the manufacture of Infrared Focal Plane arrays. Areas to be examined are wafer handling during array fabrication up through dicing, automation of Liquid Phase Epitaxy, and automation of bump bonding. The collection of factory data and its use in control of the manufacturing process will also be discussed. Specifics related to the production of Z-module architecture will be emphasized.

  8. Development of nanosilica bonded monetite cement from egg shells.

    PubMed

    Zhou, Huan; Luchini, Timothy J F; Boroujeni, Nariman Mansouri; Agarwal, Anand K; Goel, Vijay K; Bhaduri, Sarit B

    2015-05-01

    This work represents further effort from our group in developing monetite based calcium phosphate cements (CPC). These cements start with a calcium phosphate powder (MW-CPC) that is manufactured using microwave irradiation. Due to the robustness of the cement production process, we report that the starting materials can be derived from egg shells, a waste product from the poultry industry. The CPC were prepared with MW-CPC and aqueous setting solution. Results showed that the CPC hardened after mixing powdered cement with water for about 12.5±1 min. The compressive strength after 24h of incubation was approximately 8.45±1.29 MPa. In addition, adding colloidal nanosilica to CPC can accelerate the cement hardening (10±1 min) process by about 2.5 min and improve compressive strength (20.16±4.39 MPa), which is more than double the original strength. The interaction between nanosilica and CPC was monitored using an environmental scanning electron microscope (ESEM). While hardening, nanosilica can bond to the CPC crystal network for stabilization. The physical and biological studies performed on both cements suggest that they can potentially be used in orthopedics. PMID:25746244

  9. Simultaneous chromizing-aluminizing coating of low alloy steels by a halide-activated pack cementation process

    SciTech Connect

    Geib, F.D.; Rapp, R.A. . Dept. of Materials Science and Engineering)

    1992-11-01

    The simultaneous chromizing-aluminizing of low-alloy steels has achieved Kanthal-like surface compositions of 16--2lCr and 5--8 wt%Al by the use of cementation packs with a Cr-Al masteralloy and an NH[sub 4]Cl activator salt. An initial preferential deposition of Al into the alloy induces the phase transformation from austenite to ferrite at the 1150[degrees]C process temperature. The low solubility of carbon in ferrite results in the rejection of solute C into the core of the austenitic substrate, thereby preventing the formation of an external Cr-carbide layer, which would otherwise block aluminizing and chromizing. The deposition and rapid diffusion of Cr and Al into the external bcc ferrite layer follows. Parabolic cyclic oxidation kinetics for alumina growth in air were observed over a wide range of relatively low temperatures (637--923[degrees]C).

  10. Simultaneous chromizing-aluminizing coating of low alloy steels by a halide-activated pack cementation process

    SciTech Connect

    Geib, F.D.; Rapp, R.A.

    1992-11-01

    The simultaneous chromizing-aluminizing of low-alloy steels has achieved Kanthal-like surface compositions of 16--2lCr and 5--8 wt%Al by the use of cementation packs with a Cr-Al masteralloy and an NH{sub 4}Cl activator salt. An initial preferential deposition of Al into the alloy induces the phase transformation from austenite to ferrite at the 1150{degrees}C process temperature. The low solubility of carbon in ferrite results in the rejection of solute C into the core of the austenitic substrate, thereby preventing the formation of an external Cr-carbide layer, which would otherwise block aluminizing and chromizing. The deposition and rapid diffusion of Cr and Al into the external bcc ferrite layer follows. Parabolic cyclic oxidation kinetics for alumina growth in air were observed over a wide range of relatively low temperatures (637--923{degrees}C).

  11. Influence of ferrite phase in alite-calcium sulfoaluminate cements

    NASA Astrophysics Data System (ADS)

    Duvallet, Tristana Yvonne Francoise

    Since the energy crisis in 1970's, research on low energy cements with low CO2- emissions has been increasing. Numerous solutions have been investigated, and the goal of this original research is to create a viable hybrid cement with the components of both Ordinary Portland cement (OPC) and calcium sulfoaluminate cement (CSAC), by forming a material that contains both alite and calcium sulfoaluminate clinker phases. Furthermore, this research focuses on keeping the cost of this material reasonable by reducing aluminum requirements through its substitution with iron. The aim of this work would produce a cement that can use large amounts of red mud, which is a plentiful waste material, in place of bauxite known as an expensive raw material. Modified Bogue equations were established and tested to formulate this novel cement with different amounts of ferrite, from 5% to 45% by weight. This was followed by the production of cement from reagent chemicals, and from industrial by-products as feedstocks (fly ash, red mud and slag). Hydration processes, as well as the mechanical properties, of these clinker compositions were studied, along with the addition of gypsum and the impact of a ferric iron complexing additive triisopropanolamine (TIPA). To summarize this research, the influence of the addition of 5-45% by weight of ferrite phase, was examined with the goal of introducing as much red mud as possible in the process without negatively attenuate the cement properties. Based on this PhD dissertation, the production of high-iron alite-calcium sulfoaluminateferrite cements was proven possible from the two sources of raw materials. The hydration processes and the mechanical properties seemed negatively affected by the addition of ferrite, as this phase was not hydrated entirely, even after 6 months of curing. The usage of TIPA counteracted this decline in strength by improving the ferrite hydration and increasing the optimum amount of gypsum required in each composition. The mechanical data were equivalent to OPC strengths for some compositions with 25% ferrite. This preliminary work constitutes the first research phase of this novel cement and requires additional research for its improvement. Topics for additional research are identified in this dissertation. KEYWORDS: alite, calcium sulfoaluminate, ferrite, low-energy cement, triisopropanolamine.

  12. Comparing Product Development Processes and Managing Risk

    E-print Network

    Unger, Darian W.

    Product Development Processes (PDPs) require careful design to reduce development time, create better products and manage the risks of bringing new products to market. This paper investigates the relationship between product ...

  13. A feasibility study to use coal tar contaminated soil in asphalt cement mixture production

    SciTech Connect

    Dulam, C.S.; Hoag, G.E.; Dahmani, A.; Nadim, F.

    1996-11-01

    Coal tars are the residues produced during the gasification of coal. Traditionally, coal tars were buried onsite at the power plants or left as residuals in the bottom of gas holders. Currently, there are more than 1,500 such historic sites which will undergo site assessment in the near future. The use of coal tar residuals in asphalt-based products could result in greatly reduced disposal costs, in comparison to current methods of disposal. Present disposal practice of coal tar contaminated residuals includes disposal in hazardous waste landfills or incineration. Treatment and disposal costs are reported to be as much as $1,000/ton for current coal tar contaminated residuals disposal options. This feasibility study was performed to determine the use of coal tar contaminated soil (CTCS) in bituminous materials to produce hot asphalt mix. Mixtures of varying composition of CTCS and bituminous material were produced to perform TCLP. The air emissions during the mixing process were captured and analyzed. In this study, a bench scale investigation was performed to identify and quantify the emissions from heating the CTCS at the mixer temperature. The pilot scale investigations were performed by replacing reclaimable asphalt pavement (RAP) with CTCS during the hot asphalt mix production. The investigations were performed on two types of mixtures; using CTCS as the direct additive in the first type, and using SS-1 (slow setting asphalt emulsion) stabilized CTCS as an additive in the second type.

  14. Squeeze cementing

    SciTech Connect

    Ewert, D.P.; Kundert, D.P.; Dahl, J.A.; Dalrymple, E.D.; Gerke, R.R.

    1992-06-16

    This patent describes a method for terminating the flow of fluid from a portion of a subterranean formation into a wellbore. It comprises: placing within the wellbore adjacent the portion a volume of a slurry of hydraulic cement, permitting the volume to penetrate into the portion; and maintaining the slurry in the portion for a time sufficient to enable the slurry to form a rigid mass of cement in the portion.

  15. Productivity enhancement through process integration 

    E-print Network

    Alotaibi, Meteab Aujian

    2006-10-30

    stream_source_info etd-tamu-2005B-CHEN-Alotaibi.pdf.txt stream_content_type text/plain stream_size 205911 Content-Encoding ISO-8859-1 stream_name etd-tamu-2005B-CHEN-Alotaibi.pdf.txt Content-Type text/plain; charset=ISO-8859...-1 PRODUCTIVITY ENHANCEMENT THROUGH PROCESS INTEGRATION A Dissertation by METEAB AUJIAN ALOTAIBI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR...

  16. Cement advanced furnace component and system optimization. Volume 1. Final report, August 1989-April 1993

    SciTech Connect

    Keane, K.; Chatwani, A.; Litka, A.

    1994-10-01

    Research and development of the Cement Advanced Furnace (CAF) vertical shaft kiln has been performed under the sponsorship of the Gas Research Institute and Southern California Gas Co. by Textron Defense Systems and Fuller Co. The CAF represents a low cost, energy efficient, very low polluting alternative to traditional rotary kilns for the production of Portland and specialty cements. The testing program has resulted in the development of an integrated shaft furnace that has produced clinker in a pilot plant at rates up to 2200 lb/hr. The unit can be scaled to commercial sizes with the aid of a mathematical model of the equipment and process developed as part of this effort. Cement produced in this program is as strong as, but easier to grind than, cement produced in conventional rotary kilns. Polluting emissions from the CAF are lower than from conventional cement processing equipment by virtue of the use of natural gas as fuel and a low combustion temperature.

  17. Synthesis of aluminum-rich coatings on new high-temperature cast austenitic steel CF8C-Plus by a pack cementation process

    NASA Astrophysics Data System (ADS)

    Hall, Alex Keith

    2011-12-01

    In this research, a pack cementation process is developed for coating the newly developed cast austenitic steel CF8C-Plus. The developed coating process is capable of producing pack particle free coatings on large fatigue test specimens in a horizontal laboratory tube furnace as well as smaller oxidation and creep test samples. Several methods for the production of the pack powder free Al-rich coating are presented and evaluated for samples of both sizes. The developed coating is intended to compete with coatings of a similar quality produced with chemical vapor deposition and slurry coating methods. Additionally, because CF8C-Plus has only recently become available there is currently no available data on the effect of the fabrication of an Al-rich coating on the substrates properties. This research used advanced characterization methods to evaluate the coating surface and cross-sectional features. These methods include scanning electron microscopy, X-ray diffraction, electron probe microanalysis and energy dispersive spectroscopy analysis. This is the first time that this information has been made available to the scientific community. Also, the oxidation performance of the coating will be tested and compared to other coatings developed with CVD and slurry coating methods and the preliminary results of the effect of the coating on the alloys fatigue performance will be presented.

  18. Characterization of spatial impact of particles emitted from a cement material production facility on outdoor particle deposition in the surrounding community.

    PubMed

    Yu, Chang Ho; Fan, Zhihua; McCandlish, Elizabeth; Stern, Alan H; Lioy, Paul J

    2011-10-01

    The objective of this study was to estimate the contribution of a facility that processes steel production slag into raw material for cement production to local outdoor particle deposition in Camden, NJ. A dry deposition sampler that can house four 37-mm quartz fiber filters was developed and used for the collection of atmospheric particle deposits. Two rounds of particle collection (3-4 weeks each) were conducted in 8-11 locations 200-800 m downwind of the facility. Background samples were concurrently collected in a remote area located -2 km upwind from the facility. In addition, duplicate surface wipe samples were collected side-by-side from each of the 13 locations within the same sampling area during the first deposition sampling period. One composite source material sample was also collected from a pile stored in the facility. Both the bulk of the source material and the < 38 microm fraction subsample were analyzed to obtain the elemental source profile. The particle deposition flux in the study area was higher (24-83 mg/m2 x day) than at the background sites (13-17 mg/m2day). The concentration of Ca, a major element in the cement source production material, was found to exponentially decrease with increasing downwind distance from the facility (P < 0.05). The ratio of Ca/Al, an indicator of Ca enrichment due to anthropogenic sources in a given sample, showed a similar trend. These observations suggest a significant contribution of the facility to the local particle deposition. The contribution of the facility to outdoor deposited particle mass was further estimated by three independent models using the measurements obtained from this study. The estimated contributions to particle deposition in the study area were 1.8-7.4% from the regression analysis of the Ca concentration in particle deposition samples against the distance from the facility, 0-11% from the U.S. Environmental Protection Agency (EPA) Chemical Mass Balance (CMB) source-receptor model, and 7.6-13% from the EPA Industrial Source Complex Short Term (ISCST3) dispersion model using the particle-size-adjusted permit-based emissions estimates. PMID:22070034

  19. Characterization of Spatial Impact of Particles Emitted from a Cement Material Production Facility on Outdoor Particle Deposition in the Surrounding Community

    PubMed Central

    Yu, Chang Ho; Fan, Zhihua (Tina); McCandlish, Elizabeth; Stern, Alan H.; Lioy, Paul J.

    2014-01-01

    The objective of this study was to estimate the contribution of a facility that processes steel production slag into raw material for cement production to local outdoor particle deposition in Camden, NJ. A dry deposition sampler that can house four 37-mm quartz fiber filters was developed and used for the collection of atmospheric particle deposits. Two rounds of particle collection (3–4 weeks each) were conducted in 8–11 locations 200–800 m downwind of the facility. Background samples were concurrently collected in a remote area located ~2 km upwind from the facility. In addition, duplicate surface wipe samples were collected side-by-side from each of the 13 locations within the same sampling area during the first deposition sampling period. One composite source material sample was also collected from a pile stored in the facility. Both the bulk of the source material and the <38 ?m fraction subsample were analyzed to obtain the elemental source profile. The particle deposition flux in the study area was higher (24–83 mg/m2 day) than at the background sites (13–17 mg/m2·day). The concentration of Ca, a major element in the cement source production material, was found to exponentially decrease with increasing downwind distance from the facility (P < 0.05). The ratio of Ca/Al, an indicator of Ca enrichment due to anthropogenic sources in a given sample, showed a similar trend. These observations suggest a significant contribution of the facility to the local particle deposition. The contribution of the facility to outdoor deposited particle mass was further estimated by three independent models using the measurements obtained from this study. The estimated contributions to particle deposition in the study area were 1.8–7.4% from the regression analysis of the Ca concentration in particle deposition samples against the distance from the facility, 0–11% from the U.S. Environmental Protection Agency (EPA) Chemical Mass Balance (CMB) source-receptor model, and 7.6–13% from the EPA Industrial Source Complex Short Term (ISCST3) dispersion model using the particle-size-adjusted permit-based emissions estimates. PMID:22070034

  20. Durability of pulp fiber-cement composites

    NASA Astrophysics Data System (ADS)

    Mohr, Benjamin J.

    Wood pulp fibers are a unique reinforcing material as they are non-hazardous, renewable, and readily available at relatively low cost compared to other commercially available fibers. Today, pulp fiber-cement composites can be found in products such as extruded non-pressure pipes and non-structural building materials, mainly thin-sheet products. Although natural fibers have been used historically to reinforce various building materials, little scientific effort has been devoted to the examination of natural fibers to reinforce engineering materials until recently. The need for this type of fundamental research has been emphasized by widespread awareness of moisture-related failures of some engineered materials; these failures have led to the filing of national- and state-level class action lawsuits against several manufacturers. Thus, if pulp fiber-cement composites are to be used for exterior structural applications, the effects of cyclical wet/dry (rain/heat) exposure on performance must be known. Pulp fiber-cement composites have been tested in flexure to examine the progression of strength and toughness degradation. Based on scanning electron microscopy (SEM), environmental scanning electron microscopy (ESEM), energy dispersive spectroscopy (EDS), a three-part model describing the mechanisms of progressive degradation has been proposed: (1) initial fiber-cement/fiber interlayer debonding, (2) reprecipitation of crystalline and amorphous ettringite within the void space at the former fiber-cement interface, and (3) fiber embrittlement due to reprecipitation of calcium hydroxide filling the spaces within the fiber cell wall structure. Finally, as a means to mitigate kraft pulp fiber-cement composite degradation, the effects of partial portland cement replacement with various supplementary cementitious materials (SCMs) has been investigated for their effect on mitigating kraft pulp fiber-cement composite mechanical property degradation (i.e., strength and toughness losses) during wet/dry cycling. SCMs have been found to be effective in mitigating composite degradation through several processes, including a reduction in the calcium hydroxide content, stabilization of monosulfate by maintaining pore solution pH, and a decrease in ettringite reprecipitation accomplished by increased binding of aluminum in calcium aluminate phases and calcium in the calcium silicate hydrate (C-S-H) phase.

  1. Passamaquoddy Technology Recovery Scrubber{trademark} at the Dragon Products, Inc. Cement Plant located in Thomaston, Maine. 1990 Annual technical report

    SciTech Connect

    Not Available

    1990-12-31

    The background and process of the Passamaquoddy Technology Recovery Scrubber{trademark} are described. The Scrubber was developed for Dragon Cement Plant in Thomaston, Maine and facilitates a number of process improvements. The exhaust gas is scrubbed of SO{sub 2} with better than 90% efficiency. The kiln dust is cleaned of alkalines and so can be returned to kiln feed instead of dumped to landfill. Potassium sulfate in commercial quantity and purity can be recovered. Distilled water is recovered which also has commercial potential. Thus, various benefits are accrued and no waste streams remain for disposal. The process is applicable to both wet and dry process cement kilns and appears to have potential in any industry which generates acidic gaseous exhausts and/or basic solid or liquid wastes.

  2. Effect of resin cement, aging process and root level on the bond strength of the resin-fiber posts

    NASA Astrophysics Data System (ADS)

    Almuhim, Khalid Salman

    Background. Little is known about the long-term clinical bonding effectiveness of the Fiber-reinforced composite (FRC) posts cemented with self-etch adhesive systems. Bond stability and longevity of the cemented post are adversely affected by physical and chemical factors over time, such as expansion and contraction stresses caused by thermal changes and occlusal load. This clinical condition can be simulated in vitro by thermocyclic loading; and bonding effectiveness can be evaluated by applying the micropush out test. Therefore, more in vitro studies are needed to evaluate the bond strength of the fiber posts cemented with different resin cement systems after simulating the artificial aging induced by thermocycling. The aim of this study was to compare the microtensile bond strength of two different resin cement systems (total etch, and self-etch resin cement system) used for cementation of fiber reinforced composite posts in three different aging periods using thermocycling. Methods. Following IRB approval, sixty freshly extracted bicuspid single rooted natural teeth were endodontically treated, and the post-spaces were prepared to receive a fiber-post cemented with either a total etch resin cement (Rely-X Ultimate) or with a self-etch resin cement (Rely-X Unicem). No thermocycling, 20,000 and 40,000 cycles was used to age the specimens. Teeth were randomly allocated into six different groups: G1 - Control: Rely-X Ultimate cement with no thermocycling. G2: Rely-X Ultimate cement with 20,000 thermocycling. G3: Rely-X Ultimate cement with 40,000 thermocycling. G4: Rely-X Unicem cement. G5: Rely-X Unicem cement. G6: Rely-X Unicem cement. Microtensile bond strength determined using a micropush out test on a universal testing machine (MTS). Additionally, the failure mode of each specimen was observed under a stereomicroscope (Olympus) at 40x magnification. Finally, one representative sample was randomly selected from each of the five failure modes for scanning electron microscope (SEM) examination of the surface morphology in order to obtain SEM images of the failure patterns at 29--70x magnifications. Statistical analysis: Nested general linear and generalized linear model was created to look for statistical significance. Level of significance was set at P < 0.05. Results. No significant differences were found on the bond strength between the two types of resin cement systems (total etch and self-etch). Regarding the thermocycling effect, the bond strengths of the group of 40,000 cycles was significantly lower than the 20,000 cycle group. In addition, the bond strengths of the specimens collected from the coronal third of the root were significantly lower than the specimens from the apical third. A Fisher's Exact test was applied to evaluate the failure mode differences, and showed statistically significant differences between the groups. Conclusions . The bond strength to the root canal dentin did not vary with the type of resin cement systems (total-etch vs self-etch). The microtensile bond strength values of FRC posts were significantly affected by increasing the thermocycling, and were significantly different among the different longitudinal levels of the root canal.

  3. Utilization of municipal solid waste incineration (MSWI) fly ash in blended cement Part 1: Processing and characterization of MSWI fly ash.

    PubMed

    Aubert, J E; Husson, B; Sarramone, N

    2006-08-25

    This paper is the first of a series of two articles dealing with the processes applied to MSWI fly ash with a view to reusing it safely in cement-based materials. Part 1 presents two stabilization processes and Part 2 deals with the use of the two treated fly ashes (TFA) in mortars. Two types of binder were used: an Ordinary Portland Cement (OPC) containing more than 95% clinker (CEM I 52.5R) and a binary blend cement composed of 70% ground granulated blast furnace slag and 30% clinker (CEM III-B 42.5N). In this first part, two stabilization processes are presented: the conventional process, called "A", based on the washing, phosphation and calcination of the ash, and a modified process, called "B", intended to eliminate metallic aluminum and sulfate contained in the ash. The physical, chemical and mineralogical characteristics of the two TFA were comparable. The main differences observed were those expected, i.e. TFA-B was free of metallic aluminum and sulfate. The mineralogical characterization of the two TFAs highlighted the presence of large amounts of a calcium aluminosilicate phase taking two forms, a crystalline form (gehlenite) and an amorphous form. Hydration studies on pastes containing mixed TFA and calcium hydroxide showed that this phase reacted with calcium hydroxide to form calcium aluminate hydrates. This formation of hydrates was accompanied by a hardening of the pastes. These results are very encouraging for the reuse of such TFA in cement-based materials because they can be considered as pozzolanic additions and could advantageously replace a part of the cement in cement-based materials. Finally, leaching tests were carried out to evaluate the environmental impact of the two TFAs. The elements which were less efficiently stabilized by process A were zinc, cadmium and antimony but, when the results of the leaching tests were compared with the thresholds of the European landfill directive, TFA-A could nevertheless be accepted at landfills for non-hazardous waste. The modifications of the process led to a significant reduction in the stabilization of chromium, selenium and antimony. PMID:16442718

  4. Effect of Eu-citrate complex composition on its cementation

    SciTech Connect

    Lebedev, V.M.; Kornilov, A.S.; Yadovin, A.A.

    1995-03-01

    The dependence of Eu cementation by sodium amalgam in a semicountercurrent regime from citrate solutions on the Eu complex composition is studied. The purity of the {sup 153}Gd product from radioactive Eu can be increased during cementation by introducing correcting solutions of citric acid and stable Eu. The selected conditions are verified by processing irradiated targets. The content of radioactive Eu in the {sup 153}Gd product is reduced from 0.01 to 0.0005% with respect to {gamma}-activity.

  5. Synthesis of Portland cement and calcium sulfoaluminate-belite cement for sustainable development and performance

    NASA Astrophysics Data System (ADS)

    Chen, Irvin Allen

    Portland cement concrete, the most widely used manufactured material in the world, is made primarily from water, mineral aggregates, and portland cement. The production of portland cement is energy intensive, accounting for 2% of primary energy consumption and 5% of industrial energy consumption globally. Moreover, portland cement manufacturing contributes significantly to greenhouse gases and accounts for 5% of the global CO2 emissions resulting from human activity. The primary objective of this research was to explore methods of reducing the environmental impact of cement production while maintaining or improving current performance standards. Two approaches were taken, (1) incorporation of waste materials in portland cement synthesis, and (2) optimization of an alternative environmental friendly binder, calcium sulfoaluminate-belite cement. These approaches can lead to less energy consumption, less emission of CO2, and more reuse of industrial waste materials for cement manufacturing. In the portland cement part of the research, portland cement clinkers conforming to the compositional specifications in ASTM C 150 for Type I cement were successfully synthesized from reagent-grade chemicals with 0% to 40% fly ash and 0% to 60% slag incorporation (with 10% intervals), 72.5% limestone with 27.5% fly ash, and 65% limestone with 35% slag. The synthesized portland cements had similar early-age hydration behavior to commercial portland cement. However, waste materials significantly affected cement phase formation. The C3S--C2S ratio decreased with increasing amounts of waste materials incorporated. These differences could have implications on proportioning of raw materials for cement production when using waste materials. In the calcium sulfoaluminate-belite cement part of the research, three calcium sulfoaluminate-belite cement clinkers with a range of phase compositions were successfully synthesized from reagent-grade chemicals. The synthesized calcium sulfoaluminate-belite cement that contained medium C4A3 S¯ and C2S contents showed good dimensional stability, sulfate resistance, and compressive strength development and was considered the optimum phase composition for calcium sulfoaluminate-belite cement in terms of comparable performance characteristics to portland cement. Furthermore, two calcium sulfoaluminate-belite cement clinkers were successfully synthesized from natural and waste materials such as limestone, bauxite, flue gas desulfurization sludge, Class C fly ash, and fluidized bed ash proportioned to the optimum calcium sulfoaluminate-belite cement synthesized from reagent-grade chemicals. Waste materials composed 30% and 41% of the raw ingredients. The two calcium sulfoaluminate-belite cements synthesized from natural and waste materials showed good dimensional stability, sulfate resistance, and compressive strength development, comparable to commercial portland cement.

  6. Chemical production processes and systems

    DOEpatents

    Holladay, Johnathan E; Muzatko, Danielle S; White, James F; Zacher, Alan H

    2015-04-21

    Hydrogenolysis systems are provided that can include a reactor housing an Ru-comprising hydrogenolysis catalyst and wherein the contents of the reactor is maintained at a neutral or acidic pH. Reactant reservoirs within the system can include a polyhydric alcohol compound and a base, wherein a weight ratio of the base to the compound is less than 0.05. Systems also include the product reservoir comprising a hydrogenolyzed polyhydric alcohol compound and salts of organic acids, and wherein the moles of base are substantially equivalent to the moles of salts or organic acids. Processes are provided that can include an Ru-comprising catalyst within a mixture having a neutral or acidic pH. A weight ratio of the base to the compound can be between 0.01 and 0.05 during exposing.

  7. Chemical production processes and systems

    SciTech Connect

    Holladay, Johnathan E.; Muzatko, Danielle S.; White, James F.; Zacher, Alan H.

    2014-06-17

    Hydrogenolysis systems are provided that can include a reactor housing an Ru-comprising hydrogenolysis catalyst and wherein the contents of the reactor is maintained at a neutral or acidic pH. Reactant reservoirs within the system can include a polyhydric alcohol compound and a base, wherein a weight ratio of the base to the compound is less than 0.05. Systems also include the product reservoir comprising a hydrogenolyzed polyhydric alcohol compound and salts of organic acids, and wherein the moles of base are substantially equivalent to the moles of salts or organic acids. Processes are provided that can include an Ru-comprising catalyst within a mixture having a neutral or acidic pH. A weight ratio of the base to the compound can be between 0.01 and 0.05 during exposing.

  8. Process for capturing CO2 arising from the calcination of the CaCO3 used in cement manufacture.

    PubMed

    Rodríguez, N; Alonso, M; Grasa, G; Abanades, J Carlos

    2008-09-15

    This paper outlines a new CaCO3 calcination method for producing a stream of CO2 (suitable for permanent geological storage after purification and compression). The process is based on the use of very hot CaO particles (T >1000 degrees C) to transfer heat from a circulating fluidized bed combustor (CFBC) to a calciner (fluidized with CO2 and/or steam). Since the fluidized bed combustor and calciner have separate atmospheres, the CO2 resulting from the decomposition of CaCO3 can be captured, while the CO2 generated in the combustion of the fuel in air is emitted to the atmosphere. We demonstrate that with this system it is possible to reduce the CO2 emissions of a cement plant by around 60%. Furthermore, since the key pieces of equipment are similar to the commercial CFBCs used in power generation plants, it is possible to establish the additional investment required for the system and to estimate the cost per ton of CO2 avoided for this process to be about 19 $/tCO2 avoided. PMID:18853819

  9. Rigless multizone recompletion using a cement packer placed with coiled tubing: A case history

    SciTech Connect

    Nowak, T.W.; Patout, T.S.

    1997-12-01

    Cement packers have been used for some time when reserve estimates have not justified the cost of major rig remedial work. They typically provide a means of zonal isolation of the last reserves in an existing wellbore. The success of these operations has historically been low. This is predominantly because of poor cement bonding in the annulus between the tubing and production casing. Because of the minimal amount of equipment on location and lack of upfront design work involved, most cement packers are doomed to failure before they are even placed. Cement packers have been placed using a large number of methods. In the Ship Shoal 181 field, Well B-4 would not economically justify a major rig workover, even though there were several uphole gas sands capable of producing in this well. With proper upfront planning and design, it would be economical; however, all these reserves could be produced in a through-tubing process using a cement packer. This case history presents a refined look at existing technology involving placement of a cement packer and reviews problems common to cement-packer completions, including a case history. Solutions are also discussed for successfully completing and recovering reserves from not one but several remaining gas intervals. This paper reviews the design considerations and precautions, along with the production results and economics, for placing what is believed to be the largest cement packer placed through coiled tubing.

  10. A Thermoelectric Waste-Heat-Recovery System for Portland Cement Rotary Kilns

    NASA Astrophysics Data System (ADS)

    Luo, Qi; Li, Peng; Cai, Lanlan; Zhou, Pingwang; Tang, Di; Zhai, Pengcheng; Zhang, Qingjie

    2015-06-01

    Portland cement is produced by one of the most energy-intensive industrial processes. Energy consumption in the manufacture of Portland cement is approximately 110-120 kWh ton-1. The cement rotary kiln is the crucial equipment used for cement production. Approximately 10-15% of the energy consumed in production of the cement clinker is directly dissipated into the atmosphere through the external surface of the rotary kiln. Innovative technology for energy conservation is urgently needed by the cement industry. In this paper we propose a novel thermoelectric waste-heat-recovery system to reduce heat losses from cement rotary kilns. This system is configured as an array of thermoelectric generation units arranged longitudinally on a secondary shell coaxial with the rotary kiln. A mathematical model was developed for estimation of the performance of waste heat recovery. Discussions mainly focus on electricity generation and energy saving, taking a ?4.8 × 72 m cement rotary kiln as an example. Results show that the Bi2Te3-PbTe hybrid thermoelectric waste-heat-recovery system can generate approximately 211 kW electrical power while saving 3283 kW energy. Compared with the kiln without the thermoelectric recovery system, the kiln with the system can recover more than 32.85% of the energy that used to be lost as waste heat through the kiln surface.

  11. Wood Technology: Techniques, Processes, and Products

    ERIC Educational Resources Information Center

    Oatman, Olan

    1975-01-01

    Seven areas of wood technology illustrates applicable techniques, processes, and products for an industrial arts woodworking curriculum. They are: wood lamination; PEG (polyethylene glycol) diffusion processes; wood flour and/or particle molding; production product of industry; WPC (wood-plastic-composition) process; residential construction; and…

  12. Effect of sepiolite on the flocculation of suspensions of fibre-reinforced cement

    SciTech Connect

    Jarabo, Rocio; Fuente, Elena; Moral, Ana; Blanco, Angeles; Negro, Carlos

    2010-10-15

    Sepiolite is used to increase thixotropy of cement slurries for easier processing, to prevent sagging and to provide a better final quality in the manufacture of fibre-reinforced cement products. However, the effect of sepiolite on flocculation and its interactions with the components of fibre cement are yet unknown. The aim of this research is to study the effects of sepiolite on the flocculation of different fibre-reinforced cement slurries induced by anionic polyacrylamides (A-PAMs). Flocculation and floc properties were studied by monitoring the chord size distribution in real time employing a focused beam reflectance measurement (FBRM) probe. The results show that sepiolite increases floc size and floc stability in fibre-cement suspensions. Sepiolite competes with fibres and clay for A-PAMs adsorption and its interaction with A-PAM improves flocculation of mineral particles.

  13. FORMATION OF A DETACHED PLUME FROM A CEMENT PLANT

    EPA Science Inventory

    A coordinated study of process, source emissions, and plume sampling was conducted at a coal-fired cement production plant. Both source and plume sampling consisted of particle and gas measurement and characterization. Particulate sampling of both the source and plume addressed p...

  14. Nanostructured TaxC interlayer synthesized via double glow plasma surface alloying process for diamond deposition on cemented carbide

    NASA Astrophysics Data System (ADS)

    Rong, Wolong; Hei, Hongjun; Zhong, Qiang; Shen, Yanyan; Liu, Xiaoping; Wang, Xin; Zhou, Bing; He, Zhiyong; Yu, Shengwang

    2015-12-01

    The aim in this work was to improve the adhesion of diamond coating with pre-deposition of a TaxC interlayer on cemented carbide (WC-Co) substrate by double glow plasma surface alloying technique. The following deposition of diamond coating on the interlayer was performed in a microwave plasma chemical vapor deposition (MPCVD) reactor. TaxC interlayer with an inner diffusion layer and an outer deposition layer was composed of Ta2C and TaC nanocrystalline, and it exhibited a special compact surface morphology formed of flower-shaped pits. As the gradual element distributions existed in the diffusion layer, the interlayer displayed a superior adherence to the substrate with significantly enhanced surface microhardness to the original substrate. After CVD process, the preferred orientation of TaC changed from (2 2 2) to (2 0 0) plane, and a uniform and tense diamond coating with adhesion referred to class HF 2 at least (Verein Deutscher Ingenieure 3198 norm) was obtained on the interlayered substrate. It indicated that the diffusion of Co was effectively inhibited by the formation of TaxC diffusion-deposition interlayer. The TaxC interlayer is most likely to improve the performance of diamond coatings used in cutting tools.

  15. Utilization of gold tailings as an additive in Portland cement.

    PubMed

    Celik, Ozlem; Elbeyli, Iffet Yakar; Piskin, Sabriye

    2006-06-01

    Mine tailings are formed as an industrial waste during coal and ore mining and processing. In the investigated process, following the extraction of gold from the ore, the remaining tailings are subjected to a two-stage chemical treatment in order to destroy the free cyanide and to stabilize and coagulate heavy metals prior to discharge into the tailings pond. The aim of this study was the investigation of the feasibility of utilization of the tailings as an additive material in Portland cement production. For this purpose, the effects of the tailings on the compressive strength properties of the ordinary Portland cement were investigated. Chemical and physical properties, mineralogical composition, particle size distribution and microstructure of the tailings were determined by Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), particle size analyzer (Mastersizer) and scanning electron microscope (SEM). Following the characterization of the tailings, cement mortars were prepared by intergrinding Portland cement with dried tailings. Composition of the cement clinkers were adjusted to contain 5, 15, 25% (wt/wt) dried tailings and also silica fume and fly ash samples (C and F type) were added to clinker in different ratios. The mortars produced with different amounts of tailings, silica fume, fly ashes and also mixtures of them were tested for compressive strength values after 2, 7, 28 and 56 days according to the European Standard (EN 196-1). The results indicated that gold tailings up to 25% in clinker could be beneficially used as an additive in Portland cement production. It is suggested that the gold tailings used in the cement are blended with silica fume and C-type fly ash to obtain higher compressive strength values. PMID:16784164

  16. Effects of supercritical carbon dioxide on well cements

    SciTech Connect

    Onan, D.D.

    1984-03-01

    Due to the widespread manifestation of large scale miscible CO/sub 2/ enhanced recovery projects, particularly in West Texas and Gulf Coast regions, considerable concern has developed regarding the performance and/or durability of hydrated cement located across producing and injection intervals in CO/sub 2/ related wells. It is known that carbonation affects the microstructure of cement affecting both porosity and compressive strength. The CO/sub 2/ reactivity of a cement is characterized not only by its chemical composition, but also by the properties of the CO/sub 2/ medium itself, that is, partial pressure, temperature and relative humidity. However, a clear understanding of this phenomenon and its effects on portland cement is still not completely substantiated, giving rise to contradictory opinions in this particular area of research. This led to the need and development of a laboratory program for examining the effects of supercritical CO/sub 2/ on preset cement, as well as the influence of carbonation on the early stages of the cement hydration process. This article presents the findings of a comprehensive study which show that after prolonged exposure to CO/sub 2/ under supercritical conditions, the hydration products formed in the hydration of common portland cement undergo decomposition into calcium carbonate and a siliceous residue. Cement samples exposed to the lower extremes (temperature and pressure) of a supercritical CO/sub 2/ environment exhibited greater reactivity under dynamic conditions as compared to static conditions, while increasing CO/sub 2/ pressure increased the degree of reaction regardless of the carbonation conditions employed.

  17. Cement manufacture and the environment - Part I: Chemistry and technology

    USGS Publications Warehouse

    Van Oss, H. G.; Padovani, A.C.

    2002-01-01

    Hydraulic (chiefly portland) cement is the binding agent in concrete and mortar and thus a key component of a country's construction sector. Concrete is arguably the most abundant of all manufactured solid materials. Portland cement is made primarily from finely ground clinker, which itself is composed dominantly of hydraulically active calcium silicate minerals formed through high-temperature burning of limestone and other materials in a kiln. This process requires approximately 1.7 tons of raw materials perton of clinker produced and yields about 1 ton of carbon dioxide (CO2) emissions, of which calcination of limestone and the combustion of fuels each contribute about half. The overall level of CO2 output makes the cement industry one of the top two manufacturing industry sources of greenhouse gases; however, in many countries, the cement industry's contribution is a small fraction of that from fossil fuel combustion by power plants and motor vehicles. The nature of clinker and the enormous heat requirements of its manufacture allow the cement industry to consume a wide variety of waste raw materials and fuels, thus providing the opportunity to apply key concepts of industrial ecology, most notably the closing of loops through the use of by-products of other industries (industrial symbiosis). In this article, the chemistry and technology of cement manufacture are summarized. In a forthcoming companion article (part II), some of the environmental challenges and opportunities facing the cement industry are described. Because of the size and scope of the U.S. cement industry, the analysis relies primarily on data and practices from the United States.

  18. The 3Rs and cement kiln dust: Opportunities for reduction, reuse and recycling

    SciTech Connect

    Nisbet, M.

    1997-12-31

    Cement kiln dust (CKD) is a by-product of the cement manufacturing process. This material which is captured in cement kiln dust control equipment consists primarily of raw and partly calcined kiln feed. Factors which contribute to the generation of CKD are described. Cases of successful reduction of CKD generation are presented. Technologies for treating CKD so that it can be reused as a raw material for cement production are discussed. Applications where CKD can be used alone or with other by-products are also presented. Opportunities for developing new uses for CKD are identified and discussed in terms of the drivers behind such applications as well as the economic, technical and regulatory barriers to their development.

  19. Field pilot study on emissions, formations and distributions of PCDD/Fs from cement kiln co-processing fly ash from municipal solid waste incinerations.

    PubMed

    Liu, Guorui; Zhan, Jiayu; Zheng, Minghui; Li, Li; Li, Chunping; Jiang, Xiaoxu; Wang, Mei; Zhao, Yuyang; Jin, Rong

    2015-12-15

    A pilot study was performed to evaluate formation, distribution and emission of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from cement kilns that co-process fly ash from municipal solid waste incineration (MSWI). Stack gas and particulate samples from multiple stages in the process were collected and analyzed for PCDD/Fs. Stack emissions of PCDD/Fs were below the European Union limit for cement kilns (0.1ngTEQm(-3)). PCDD/F concentrations in particulates from the cyclone preheater outlet, suspension preheater boiler, humidifier tower, and back-end bag filter were much higher than in other samples, which suggests that these areas are the major sites of PCDD/F formation. Comparison of PCDD/F homolog and congener profiles from different stages suggested that tetra- and penta-chlorinated furans were mainly formed during cement kiln co-processing of MSWI fly ash. Three lower chlorinated furan congeners, including 2,3,7,8-tetrachlorodibenzofuran, 1,2,3,7,8-pentachlorodibenzo-p-dioxin and 2,3,4,7,8-pentachlorodibenzofuran, were identified as dominant contributors to the toxic equivalents (TEQ) of the PCDD/Fs. The concentration of PCDD/Fs in particulates was correlated with chloride content, which is consistent with its positive effect on PCDD/F formation. This could be mitigated by pretreating the feedstock to remove chloride and metals. Mass balance indicated that cement kilns eliminated about 94% of the PCDD/F TEQ input from the feedstock. PMID:26241773

  20. Mechanical properties of WC10Co cemented carbides sintered from nanocrystalline spray conversion processed powders

    E-print Network

    Hong, Soon Hyung

    -tungstate (AMT) and cobalt nitrate. The WC powders were about 100 nm in diameter mixed homogeneously with Co in a diameter range of 0.57±4 lm were mixed with Co powders, and were sintered at the same conditions as those processed powders Seung I. Cha a , Soon H. Hong a,*, Gook H. Ha b , Byung K. Kim b a Department of Materials

  1. Processed .ishery Products .RESH AND .ROZEN

    E-print Network

    Processed .ishery Products 50 .RESH AND .ROZEN .ISH .ILLETS AND STEAKS. In 2001 the U.S. production. Alaskapollockfilletsandblocksledallspecieswith271.3 million pounds57 percent of the total. Production of groundfish fillets and steaks (see Glossary Section- Groundfish) was 336.8 million pounds. .ISH STICKS AND PORTIONS. The combined production

  2. PROCESSED FISHERY PRODUCTS FRESH AND FROZEN

    E-print Network

    PROCESSED FISHERY PRODUCTS FRESH AND FROZEN FISH FILLETS AND STEAKS. In 1998 the U.S. production. Production of groundfish fillets and steaks (see Glossary Section-Groundfish) was 269.0 million pounds. FISH STICKS AND PORTIONS. The combined production of fish sticks and portions was 243.4 million pounds valued

  3. Processed .ishery Products .RESH AND .ROZEN

    E-print Network

    Processed .ishery Products 50 .RESH AND .ROZEN .ISH .ILLETS AND STEAKS. In 2002 the U.S. production. Alaskapollockfilletsandblocksledallspecieswith304.1 million pounds59 percent of the total. Production of groundfish fillets and steaks (see Glossary Section- Groundfish) was 382.7 million pounds. .ISH STICKS AND PORTIONS. The combined production

  4. Processed Fishery Products FRESH AND FROZEN

    E-print Network

    Processed Fishery Products 47 FRESH AND FROZEN FISH FILLETS AND STEAKS. In 2004 the U.S. production pollockfilletsandblocksledallspecieswith384.4million pounds­65 percent of the total. Production of ground- fish fillets and steaks (see Glossary Section-Groundfish) was 477.3 million pounds. FISH STICKS AND PORTIONS. The combined production

  5. Processed Fishery Products FRESH AND FROZEN

    E-print Network

    Processed Fishery Products 42 FRESH AND FROZEN FISH FILLETS AND STEAKS. In 2007 the U.S. production pollockfilletsandblocksledallspecieswith396.1million pounds­64 percent of the total. Production of ground- fish fillets and steaks (see Glossary Section-Groundfish) was 477.3 million pounds. FISH STICKS AND PORTIONS. The combined production

  6. Processed Fishery Products FRESH AND FROZEN

    E-print Network

    Processed Fishery Products 42 FRESH AND FROZEN FISH FILLETS AND STEAKS. In 2008 the U.S. production. Production of ground- fish fillets and steaks (see Glossary Section-Groundfish) was 391.5 million pounds. FISH STICKS AND PORTIONS. The combined production of fish sticks and portions was 286.7 million pounds

  7. Processed Fishery Products FRESH AND FROZEN

    E-print Network

    Processed Fishery Products 42 FRESH AND FROZEN FISH FILLETS AND STEAKS. In 2006 the U.S. production pollockfilletsandblocksledallspecieswith398.0million pounds­63 percent of the total. Production of ground- fish fillets and steaks (see Glossary Section-Groundfish) was 498.8 million pounds. FISH STICKS AND PORTIONS. The combined production

  8. Processed Fishery Products FRESH AND FROZEN

    E-print Network

    Processed Fishery Products 53 FRESH AND FROZEN FISH FILLETS AND STEAKS. In 2003 the U.S. production pollockfilletsandblocksledallspecieswith366.5million pounds­60 percent of the total. Production of ground- fish fillets and steaks (see Glossary Section-Groundfish) was 465.6 million pounds. FISH STICKS AND PORTIONS. The combined production

  9. Processed Fishery Products FRESH AND FROZEN

    E-print Network

    Processed Fishery Products 42 FRESH AND FROZEN FISH FILLETS AND STEAKS. In 2005 the U.S. production pollockfilletsandblocksledallspecieswith383.3million pounds­63 percent of the total. Production of ground- fish fillets and steaks (see Glossary Section-Groundfish) was 484.5 million pounds. FISH STICKS AND PORTIONS. The combined production

  10. Process for impregnating a concrete or cement body with a polymeric material

    DOEpatents

    Mattus, A.J.; Spence, R.D.

    1988-05-04

    A process for impregnating cementitious solids with polymeric materials by blending polymeric materials in a grout, allowing the grout to cure, and contacting the resulting solidified grout containing the polymeric materials with an organic mixture containing a monomer, a cross-linking agent and a catalyst. The mixture dissolves the polymerized particles and forms a channel for distributing the monomer throughout the network formed by the polymeric particles. The organic components are then cured to form a substantially water-impermeable mass.

  11. Process for impregnating a concrete or cement body with a polymeric material

    DOEpatents

    Mattus, Alfred J. (Kingston, TN); Spence, Roger D. (Clinton, TN)

    1989-01-01

    A process for impregnating cementitious solids with polymeric materials by blending polymeric materials in a grout, allowing the grout to cure, and contacting the resulting solidified grout containing the polymeric materials with an organic mixture containing a monomer, a cross-linking agent and a catalyst. The mixture dissolves the polymerized particles and forms a channel for distributing the monomer throughout the network formed by the polymeric particles. The organic components are then cured to form a substantially water-impermeable mass.

  12. Natural cement as the precursor of Portland cement: Methodology for its identification

    SciTech Connect

    Varas, M.J. . E-mail: mjvaras@geo.ucm.es; Alvarez de Buergo, M.; Fort, R.

    2005-11-15

    When cements appeared in the 19th century, they took the place of traditional binding materials (lime, gypsum, and hydraulic lime) which had been used until that time. Early cements can be divided into two groups, natural and artificial (Portland) cements. Natural cements were introduced first, but their widespread usage was short-lived as they were quickly replaced by artificial cements (Portland), still the most important and predominant today. The main differences between natural and artificial cements arise during the manufacturing process. The final properties of the cements are greatly influenced by differences in the raw materials and burning temperatures employed. The aim of this paper is to assess the efficiency of traditional analytical techniques (petrographic microscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR)) used to differentiate natural and artificial cements.

  13. Micro- and nano-scale characterization to study the thermal degradation of cement-based materials

    SciTech Connect

    Lim, Seungmin Mondal, Paramita

    2014-06-01

    The degradation of hydration products of cement is known to cause changes in the micro- and nano-structure, which ultimately drive thermo-mechanical degradation of cement-based composite materials at elevated temperatures. However, a detailed characterization of these changes is still incomplete. This paper presents results of an extensive experimental study carried out to investigate micro- and nano-structural changes that occur due to exposure of cement paste to high temperatures. Following heat treatment of cement paste up to 1000 °C, damage states were studied by compressive strength test, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) atomic force microscopy (AFM) and AFM image analysis. Using experimental results and research from existing literature, new degradation processes that drive the loss of mechanical properties of cement paste are proposed. The development of micro-cracks at the interface between unhydrated cement particles and paste matrix, a change in C–S–H nano-structure and shrinkage of C–S–H, are considered as important factors that cause the thermal degradation of cement paste. - Highlights: • The thermal degradation of hydration products of cement is characterized at micro- and nano-scale using scanning electron microscopy (SEM) and atomic force microscopy (AFM). • The interface between unhydrated cement particles and the paste matrix is considered the origin of micro-cracks. • When cement paste is exposed to temperatures above 300 ºC, the nano-structure of C-S-H becomes a more loosely packed globular structure, which could be indicative of C-S-H shrinkage.

  14. Case study of an MBT plant producing SRF for cement kiln co-combustion, coupled with a bioreactor landfill for process residues.

    PubMed

    Grosso, Mario; Dellavedova, Stefano; Rigamonti, Lucia; Scotti, Sergio

    2016-01-01

    The paper describes the performances of the energy recovery pathway from the residual waste based on the production of a Solid Recovered Fuel (SRF) to be exploited via co-combustion in a cement kiln. The SRF is produced in a single stream Mechanical-Biological Treatment plant, where bio-drying of the waste is followed by mechanical refining in order to fulfil the quality requirements by the cement kilns. Peculiar of this MBT is the fact that sorting residues are disposed in a nearby landfill, managed according to a bioreactor approach, where landfill gas is collected for electric energy recovery. A detailed mass and energy balance of the system is presented based on one year operational data, followed by its Life Cycle Assessment. Results show that the system is energetically and environmentally effective, with most of the impacts being more than compensated by the savings of materials and energy. Major role in determining such outcome is the displacement of petcoke in the cement kiln, both in terms of its fossil CO2 emissions and of its life cycle impacts, including the trans-oceanic transport. To check the robustness of the results, two sensitivity analyses are performed on the landfill gas collection efficiency and on the avoided electric energy mix. PMID:26601731

  15. Shotcrete -- Understanding of the hydration process of mixes containing CAC and Portland cement and proposal for a simple rheological characterization

    SciTech Connect

    Bayoux, J.P.; Testud, M.; Guinot, D.; Willocq, J.; Capmas, A.

    1995-12-31

    In order to better understand the performances of CAC-slag cement and CAC--PC cement the hydration study of these mixes was undertaken. The hydrates which are responsible for the early stiffening/strengthening are identical in both mixes; it is only the time of appearance and amount which varies. Ettringite always forms first followed by the precipitation of C{sub 4}AH{sub 13}. They will both form faster then the temperature rises. As a complement, a simple laboratory equipment is proposed to characterize the stiffening behavior of the mixes straight after gauging.

  16. Biotechnology in Food Production and Processing

    NASA Astrophysics Data System (ADS)

    Knorr, Dietrich; Sinskey, Anthony J.

    1985-09-01

    The food processing industry is the oldest and largest industry using biotechnological processes. Further development of food products and processes based on biotechnology depends upon the improvement of existing processes, such as fermentation, immobilized biocatalyst technology, and production of additives and processing aids, as well as the development of new opportunities for food biotechnology. Improvements are needed in the characterization, safety, and quality control of food materials, in processing methods, in waste conversion and utilization processes, and in currently used food microorganism and tissue culture systems. Also needed are fundamental studies of the structure-function relationship of food materials and of the cell physiology and biochemistry of raw materials.

  17. Generative inspection process planner for integrated production

    SciTech Connect

    Brown, C.W. . Kansas City Div.); Gyorog, D.A. . Dept. of Mechanical Engineering)

    1990-04-01

    This work describes the design prototype development of a generative process planning system for dimensional inspection. The system, IPPEX (Inspection Process Planning EXpert), is a rule-based expert system for integrated production. Using as advanced product modeler, relational databases, and artificial intelligence techniques, IPPEX generates the process plan and part program for the dimensional inspection of products using CMMs. Through an application interface, the IPPEX system software accesses product definition from the product modeler. The modeler is a solid geometric modeler coupled with a dimension and tolerance modeler. Resource data regarding the machines, probes, and fixtures are queried from databases. IPPEX represents inspection process knowledge as production rules and incorporates an embedded inference engine to perform decision making. The IPPEX system, its functional architecture, system architecture, system approach, product modeling environment, inspection features, inspection knowledge, hierarchical planning strategy, user interface formats, and other fundamental issues related to inspection planning and part programming for CMMs are described. 27 refs., 16 figs., 4 tabs.

  18. Stromatolites, ooid dunes, hardgrounds, and crusted mud beds, all products of marine cementation and microbial mats in subtidal oceanic mixing zone on eastern margin of Great Bahama Bank

    SciTech Connect

    Dill, R.F.; Kendall, C.S.C.G.; Steinen, R.P.

    1989-03-01

    The interisland channels along the eastern margin of the Great Bahamas Bank contain lithified structures that owe their origin to recent marine cementation. This cementation appears to be commonly associated with a complex microbial community of plants and microorganisms living within a bank-margin oceanographic mixing zone. In this region, reversing tidal and wind-driven currents flow up to 3 knots (150 cm/sec) three hours out of each six-hour tidal period. Here, marine-cement crusted, carbonate mud beds are found interbedded within migrating ooid sand bars and dunes and are associated with growing, lithified stromatolites up to 2 m in height. These laminated mud beds are found with thicknesses of up to 1 m in subtidal depths of 4 to 8 m (12 to 25 ft). The muds appear to be homogeneous, but closer examination by SEM and under a microscope reveals they are composed of pelletoid aggregates of needle-shaped aragonite crystals with diameters of up to 50 ..mu... The size of these soft pellets is similar to the smaller grains of ooid sands that are abundant in the area. This size similarity could explain why both the mud beds are found in similar high-energy hydraulic regimes as the ooid sands, but does not suggest how or why the aggregates of pure aragonite needles form. A high production of ooid sand within this bank margin environment permits the formation of natural levees along the margins of tidal channels. The back sides of these levees are being lithified by marine cements to form hardgrounds. Skeletal and ooid sand dunes stabilized by Thallasia in channel bottoms also are becoming lithified. Grapestones form at the distributaries of flood tidal deltas of ooid sand. All of these features have a common attribute: they are continually in contact with the turbulent mixing-zone waters.

  19. Meat Products, Hydrodynamic Pressure Processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The hydrodynamic pressure process (HDP) has been shown to be very effective at improving meat tenderness in a variety of meat cuts. When compared to conventional aging for tenderization, HDP was more effective. The HDP process may offer the meat industry a new alternative for tenderizing meat in add...

  20. Guidebook for Using the Tool BEST Cement: Benchmarking and Energy Savings Tool for the Cement Industry

    SciTech Connect

    Galitsky, Christina; Price, Lynn; Zhou, Nan; Fuqiu , Zhou; Huawen, Xiong; Xuemin, Zeng; Lan, Wang

    2008-07-30

    The Benchmarking and Energy Savings Tool (BEST) Cement is a process-based tool based on commercially available efficiency technologies used anywhere in the world applicable to the cement industry. This version has been designed for use in China. No actual cement facility with every single efficiency measure included in the benchmark will likely exist; however, the benchmark sets a reasonable standard by which to compare for plants striving to be the best. The energy consumption of the benchmark facility differs due to differences in processing at a given cement facility. The tool accounts for most of these variables and allows the user to adapt the model to operational variables specific for his/her cement facility. Figure 1 shows the boundaries included in a plant modeled by BEST Cement. In order to model the benchmark, i.e., the most energy efficient cement facility, so that it represents a facility similar to the user's cement facility, the user is first required to input production variables in the input sheet (see Section 6 for more information on how to input variables). These variables allow the tool to estimate a benchmark facility that is similar to the user's cement plant, giving a better picture of the potential for that particular facility, rather than benchmarking against a generic one. The input variables required include the following: (1) the amount of raw materials used in tonnes per year (limestone, gypsum, clay minerals, iron ore, blast furnace slag, fly ash, slag from other industries, natural pozzolans, limestone powder (used post-clinker stage), municipal wastes and others); the amount of raw materials that are preblended (prehomogenized and proportioned) and crushed (in tonnes per year); (2) the amount of additives that are dried and ground (in tonnes per year); (3) the production of clinker (in tonnes per year) from each kiln by kiln type; (4) the amount of raw materials, coal and clinker that is ground by mill type (in tonnes per year); (5) the amount of production of cement by type and grade (in tonnes per year); (6) the electricity generated onsite; and, (7) the energy used by fuel type; and, the amount (in RMB per year) spent on energy. The tool offers the user the opportunity to do a quick assessment or a more detailed assessment--this choice will determine the level of detail of the energy input. The detailed assessment will require energy data for each stage of production while the quick assessment will require only total energy used at the entire facility (see Section 6 for more details on quick versus detailed assessments). The benchmarking tool provides two benchmarks--one for Chinese best practices and one for international best practices. Section 2 describes the differences between these two and how each benchmark was calculated. The tool also asks for a target input by the user for the user to set goals for the facility.

  1. Cement Kiln Flue Gas Recovery Scrubber Project

    SciTech Connect

    National Energy Technology Laboratory

    2001-11-30

    The Cement Kiln Flue Gas Recovery Scrubber Project was a technical success and demonstrated the following: CKD can be used successfully as the sole reagent for removing SO2 from cement kiln flue gas, with removal efficiencies of 90 percent or greater; Removal efficiencies for HCl and VOCs were approximately 98 percent and 70 percent, respectively; Particulate emissions were low, in the range of 0.005 to 0.007 grains/standard cubic foot; The treated CKD sorbent can be recycled to the kiln after its potassium content has been reduced in the scrubber, thereby avoiding the need for landfilling; The process can yield fertilizer-grade K2SO4, a saleable by-product; and Waste heat in the flue gas can provide the energy required for evaporation and crystallization in the by-product recovery operation. The demonstration program established the feasibility of using the Recovery Scrubber{trademark} for desulfurization of flue gas from cement kilns, with generally favorable economics, assuming tipping fees are available for disposal of ash from biomass combustion. The process appears to be suitable for commercial use on any type of cement kiln. EPA has ruled that CKD is a nonhazardous waste, provided the facility meets Performance Standards for the Management of CKD (U.S. Environmental Protection Agency 1999d). Therefore, regulatory drivers for the technology focus more on reduction of air pollutants and pollution prevention, rather than on treating CKD as a hazardous waste. Application of the Recovery Scrubbe{trademark} concept to other waste-disposal operations, where pollution and waste reductions are needed, appears promising.

  2. 76 FR 34252 - Notice Pursuant to the National Cooperative Research and Production Act of 1993; Portland Cement...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-13

    ... published a notice in the Federal Register pursuant to Section 6(b) of the Act on February 5, 1985 (50 FR... in the Federal Register pursuant to Section 6(b) of the Act on March 7, 2011 (76 FR 12370). Patricia... Cement Association Notice is hereby given that, on May 12, 2011, pursuant to Section 6(a) of the...

  3. 75 FR 4423 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Portland Cement...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-27

    ... February 5, 1985 (50 FR 5015). The last notification was filed with the Department on May 18, 2009. A notice was published in the Federal Register pursuant to Section 6(b) of the Act on August 9, 2009 (74 FR... Cement Association Notice is hereby given that, on December 14, 2009, pursuant to Section 6(a) of...

  4. A Review of Emerging Energy-efficiency and CO2 Emission-reduction Technologies for Cement and Concrete Production 

    E-print Network

    Hasanbeigi, A.; Price, L.; Lin, E.

    2012-01-01

    Globally, the cement industry accounts for approximately 5 percent of current man-made carbon dioxide (CO2) emissions. Development of new energy-efficiency and CO2 emission-reduction technologies and their deployment in the market will be key...

  5. 76 FR 12370 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Portland Cement...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-07

    ... pursuant to Section 6(b) of the Act on February 5, 1985 (50 FR 5015). The last notification was filed with... Section 6(b) of the Act January 27, 2010 (75 FR 4423). Patricia A. Brink, Director of Civil Enforcement... Cement Association Notice is hereby given that, on February 02, 2011, pursuant to Section 6(a) of...

  6. Process for improving metal production in steelmaking processes

    DOEpatents

    Pal, U.B.; Gazula, G.K.M.; Hasham, A.

    1996-06-18

    A process and apparatus for improving metal production in ironmaking and steelmaking processes is disclosed. The use of an inert metallic conductor in the slag containing crucible and the addition of a transition metal oxide to the slag are the disclosed process improvements. 6 figs.

  7. Immobilisation of heavy metal in cement-based solidification/stabilisation: A review

    SciTech Connect

    Chen, Q.Y. Tyrer, M.; Hills, C.D.; Yang, X.M.; Carey, P.

    2009-01-15

    Heavy metal-bearing waste usually needs solidification/stabilization (s/s) prior to landfill to lower the leaching rate. Cement is the most adaptable binder currently available for the immobilisation of heavy metals. The selection of cements and operating parameters depends upon an understanding of chemistry of the system. This paper discusses interactions of heavy metals and cement phases in the solidification/stabilisation process. It provides a clarification of heavy metal effects on cement hydration. According to the decomposition rate of minerals, heavy metals accelerate the hydration of tricalcium silicate (C{sub 3}S) and Portland cement, although they retard the precipitation of portlandite due to the reduction of pH resulted from hydrolyses of heavy metal ions. The chemical mechanism relevant to the accelerating effect of heavy metals is considered to be H{sup +} attacks on cement phases and the precipitation of calcium heavy metal double hydroxides, which consumes calcium ions and then promotes the decomposition of C{sub 3}S. In this work, molecular models of calcium silicate hydrate gel are presented based on the examination of {sup 29}Si solid-state magic angle spinning/nuclear magnetic resonance (MAS/NMR). This paper also reviews immobilisation mechanisms of heavy metals in hydrated cement matrices, focusing on the sorption, precipitation and chemical incorporation of cement hydration products. It is concluded that further research on the phase development during cement hydration in the presence of heavy metals and thermodynamic modelling is needed to improve effectiveness of cement-based s/s and extend this waste management technique.

  8. The effects of the mechanical–chemical stabilization process for municipal solid waste incinerator fly ash on the chemical reactions in cement paste

    SciTech Connect

    Chen, Cheng-Gang; Sun, Chang-Jung; Gau, Sue-Huai; Wu, Ching-Wei; Chen, Yu-Lun

    2013-04-15

    Highlights: ? Milling extracted MSWI fly ash. ? Increasing specific surface area, destruction of the crystalline texture, and increasing the amount of amorphous materials. ? Increasing heavy metal stability. ? Inducing pozzolanic reactions and increasing the early and later strength of the cement paste. - Abstract: A water extraction process can remove the soluble salts present in municipal solid waste incinerator (MSWI) fly ash, which will help to increase the stability of the synthetic materials produced from the MSWI fly ash. A milling process can be used to stabilize the heavy metals found in the extracted MSWI fly ash (EA) leading to the formation of a non-hazardous material. This milled extracted MSWI fly ash (MEA) was added to an ordinary Portland cement (OPC) paste to induce pozzolanic reactions. The experimental parameters included the milling time (96 h), water to binder ratios (0.38, 0.45, and 0.55), and curing time (1, 3, 7 and 28 days). The analysis procedures included inductively coupled plasma atomic emission spectroscopy (ICP/AES), BET, mercury intrusion porosimetry (MIP), X-ray diffraction (XRD), and nuclear magnetic resonance (NMR) imaging. The results of the analyses indicate that the milling process helped to stabilize the heavy metals in the MEA, with an increase in the specific surface area of about 50 times over that of OPC. The addition of the MEA to the OPC paste decreased the amount of Ca(OH){sub 2} and led to the generation of calcium–silicate–hydrates (C–S–H) which in turned increased the amount of gel pores and middle sized pores in the cement. Furthermore, a comparison shows an increase in the early and later strength over that of OPC paste without the addition of the milled extracted ash. In other words, the milling process could stabilize the heavy metals in the MEA and had an activating effect on the MEA, allowing it to partly substitute OPC in OPC paste.

  9. Fluid loss control in well cement slurries

    SciTech Connect

    Roark, D.N.; Nugent, A. Jr.; Bandlish, B.K.

    1987-11-17

    In a process of cementing subterranean well formations employing an aqueous well cement slurry, this patent describes the improvement characterized in that the slurry contains a gelatinous material that tends to plug porous zones and minimize premature water loss from the well cement slurry when present in the subterranean well formation. The gelatinous material is formed by interaction in the presence of water between (i) a sulfonated polymer and (ii) a polymer of monoallylamine.

  10. Advanced Multi-Product Coal Utilization By-Product Processing Plant

    SciTech Connect

    Thomas Robl; John Groppo

    2009-06-30

    The overall objective of this project is to design, construct, and operate an ash beneficiation facility that will generate several products from coal combustion ash stored in a utility ash pond. The site selected is LG&E's Ghent Station located in Carroll County, Kentucky. The specific site under consideration is the lower ash pond at Ghent, a closed landfill encompassing over 100 acres. Coring activities revealed that the pond contains over 7 million tons of ash, including over 1.5 million tons of coarse carbon and 1.8 million tons of fine (<10 {micro}m) glassy pozzolanic material. These potential products are primarily concentrated in the lower end of the pond adjacent to the outlet. A representative bulk sample was excavated for conducting laboratory-scale process testing while a composite 150 ton sample was also excavated for demonstration-scale testing at the Ghent site. A mobile demonstration plant with a design feed rate of 2.5 tph was constructed and hauled to the Ghent site to evaluate unit processes (i.e. primary classification, froth flotation, spiral concentration, secondary classification, etc.) on a continuous basis to determine appropriate scale-up data. Unit processes were configured into four different flowsheets and operated at a feed rate of 2.5 tph to verify continuous operating performance and generate bulk (1 to 2 tons) products for product testing. Cementitious products were evaluated for performance in mortar and concrete as well as cement manufacture process addition. All relevant data from the four flowsheets was compiled to compare product yields and quality while preliminary flowsheet designs were generated to determine throughputs, equipment size specifications and capital cost summaries. A detailed market study was completed to evaluate the potential markets for cementitious products. Results of the study revealed that the Ghent local fly ash market is currently oversupplied by more than 500,000 tpy and distant markets (i.e. Florida) are oversupplied as well. While the total US demand for ultrafine pozzolan is currently equal to demand, there is no reason to expect a significant increase in demand. Despite the technical merits identified in the pilot plant work with regard to beneficiating the entire pond ash stream, market developments in the Ohio River Valley area during 2006-2007 were not conducive to demonstrating the project at the scale proposed in the Cooperative Agreement. As a result, Cemex withdrew from the project in 2006 citing unfavorable local market conditions in the foreseeable future at the demonstration site. During the Budget Period 1 extensions provided by the DOE, CAER has contacted several other companies, including cement producers and ash marketing concerns for private cost share. Based on the prevailing demand-supply situation, these companies had expressed interest only in limited product lines, rather than the entire ash beneficiation product stream. Although CAER had generated interest in the technology, a financial commitment to proceed to Budget Period 2 could not be obtained from private companies. Furthermore, the prospects of any decisions being reached within a reasonable time frame were dim. Thus, CAER concurred with the DOE to conclude the project at the end of Budget Period 1, March 31, 2007. The activities presented in this report were carried out during the Cooperative Agreement period 08 November 2004 through 31 March 2007.

  11. PRODUCTION OF CARBON PRODUCTS USING A COAL EXTRACTION PROCESS

    SciTech Connect

    Dady Dadyburjor; Philip R. Biedler; Chong Chen; L. Mitchell Clendenin; Manoj Katakdaunde; Elliot B. Kennel; Nathan D. King; Liviu Magean; Peter G. Stansberry; Alfred H. Stiller; John W. Zondlo

    2004-08-31

    This Department of Energy National Energy Technology Laboratory sponsored project developed carbon products, using mildly hydrogenated solvents to extract the organic portion of coal to create synthetic pitches, cokes, carbon foam and carbon fibers. The focus of this effort was on development of lower cost solvents, milder hydrogenation conditions and improved yield in order to enable practical production of these products. This technology is needed because of the long-term decline in production of domestic feedstocks such as petroleum pitch and coal tar pitch. Currently, carbon products represents a market of roughly 5 million tons domestically, and 19 million tons worldwide. Carbon products are mainly derived from feedstocks such as petroleum pitch and coal tar pitch. The domestic supply of petroleum pitch is declining because of the rising price of liquid fuels, which has caused US refineries to maximize liquid fuel production. As a consequence, the long term trend has a decline in production of petroleum pitch over the past 20 years. The production of coal tar pitch, as in the case of petroleum pitch, has likewise declined significantly over the past two decades. Coal tar pitch is a byproduct of metallurgical grade coke (metcoke) production. In this industry, modern metcoke facilities are recycling coal tar as fuel in order to enhance energy efficiency and minimize environmental emissions. Metcoke production itself is dependent upon the production requirements for domestic steel. Hence, several metcoke ovens have been decommissioned over the past two decades and have not been replaced. As a consequence sources of coal tar are being taken off line and are not being replaced. The long-term trend is a reduction in coal tar pitch production. Thus import of feedstocks, mainly from Eastern Europe and China, is on the rise despite the relatively large transportation cost. To reverse this trend, a new process for producing carbon products is needed. The process must be economically competitive with current processes, and yet be environmentally friendly as well. The solvent extraction process developed uses mild hydrogenation of low cost oils to create powerful solvents that can dissolve the organic portion of coal. The insoluble portion, consisting mainly of mineral matter and fixed carbon, is removed via centrifugation or filtration, leaving a liquid solution of coal chemicals and solvent. This solution can be further refined via distillation to meet specifications for products such as synthetic pitches, cokes, carbon foam and fibers. The most economical process recycles 85% of the solvent, which itself is obtained as a low-cost byproduct from industrial processes such as coal tar or petroleum refining. Alternatively, processes have been developed that can recycle 100% of the solvent, avoiding any need for products derived from petroleum or coal tar.

  12. Early diagenetic alunite group mineral cements and alteration products of the Camp Rice Formation (Plio-Pleistocene) southern Rio Grande Rift

    SciTech Connect

    Harris, M.J.; James, W.C. ); Mack, G.H. . Dept. of Earth Sciences)

    1992-01-01

    Early diagenetic alunite group mineral cements and grain alteration products have been identified within the Camp Rice axial-fluvial facies west of Las Cruces, New Mexico. These constituents are pervasive and occur as pore occluding aggregates of euhedral crystals 5--15 [mu]m in diameter or as a finely disseminated mix with other authigenic minerals and alteration products. Approximately 19% of the total alunite is intragranular and replaces primarily volcanic rock fragments and feldspars. The diagenetic event was highly destructive to the original detrital constituents. An inferred initial average composition of Q[sub 47]F[sub 21]I[sub 32] from well indurated adjacent, calcite cemented strata of similar grain size has been altered to a composition of Q[sub 59]F[sub 20]L[sub 21]. Individual sandstone bodies exhibit a vertical zonation of cements from a lower alunite-natroalunite-gypsum assemblage to an overlying jarosite-kaolinite-silica assemblage. Jarosite-dominated strata are distinctly better indurated along the foresets and bases of individual cross-bed sets than alunite-dominated strata suggesting preferential precipitation of the former within initially higher permeability zones. The alunite group mineral constituents are believed to have developed under acidic and oxidizing conditions in a nearsurface environment. Jarosite likely formed under more acidic and oxidizing conditions than the alunite. Ascending hydrothermal waters rich in H[sub 2]S provided the necessary sulfate. The hydrothermal waters may have already been acidic or were acidified by the oxidation of H[sub 2]S. Descending oxidized meteoric waters flowing along permeable conduits and mixing with the hydrothermal waters likely controlled Eh and therefore pH of the diagenetic environment. Many of the necessary cations for alunite and jarosite genesis probably resulted from local hydrolysis of feldspars and volcanic rock fragments.

  13. Mass balance of dioxins over a cement kiln in China.

    PubMed

    Li, Yeqing; Chen, Tong; Zhang, Jiang; Meng, Weijie; Yan, Mi; Wang, Huanzhong; Li, Xiaodong

    2015-02-01

    The cement production process may be a potential source of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs, "dioxins"), due to the widespread distribution of dioxins and potential precursors in raw materials and to conditions favorable to de novo formation in the heat exchangers. The emission, gas/particle distribution, and mass balance of PCDD/Fs were investigated at a typical state-of-the-art Chinese cement kiln. Input and output inventories were established for three campaigns, including two in normal operation and one while co-processing refuse derived fuel (RDF). Sample analysis from stack gas, cement kiln dust, raw meal, fly dust and clinker for the analysis of PCDD/Fs were reported in this study. Dioxins were also analyzed at various positions in the pre-heater, presenting an adsorption-desorption circulation process of PCDD/Fs. The over-all dioxin mass balance was negative, indicating that this cement kiln is not a source but a sink process of dioxins. PMID:25532674

  14. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2002-07-30

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report includes results from laboratory testing of ULHS systems along with other lightweight cement systems, including foamed and sodium silicate slurries. During this project quarter, a comparison study of the three cement systems examined the effect that cement drillout has on the three cement systems. Testing to determine the effect of pressure cycling on the shear bond properties of the cement systems was also conducted. This report discusses testing that was performed to analyze the alkali-silica reactivity of ULHS in cement slurries.

  15. CEMENT RELATED RESEARCH HYDROGEOCHEMISTRY GROUP

    E-print Network

    Politècnica de Catalunya, Universitat

    CEMENT RELATED RESEARCH HYDROGEOCHEMISTRY GROUP Josep M. Soler Jordi Cama Carles Ayora Ana Trapote.soler@idaea.csic.es #12;NOMECLATURE cement + water = hardened cement paste cement + water + sand = mortar cement + waterC) clinker + gypsum portland cement PORTLAND CEMENT #12;GTS-HPF Core Infiltration Experiment Experimental

  16. Benchmarking Peer Production Mechanisms, Processes & Practices

    ERIC Educational Resources Information Center

    Fischer, Thomas; Kretschmer, Thomas

    2008-01-01

    This deliverable identifies key approaches for quality management in peer production by benchmarking peer production practices and processes in other areas. (Contains 29 footnotes, 13 figures and 2 tables.)[This report has been authored with contributions of: Kaisa Honkonen-Ratinen, Matti Auvinen, David Riley, Jose Pinzon, Thomas Fischer, Thomas…

  17. Cell culture processes for monoclonal antibody production

    PubMed Central

    Li, Feng; Vijayasankaran, Natarajan; Shen, Amy (Yijuan); Kiss, Robert

    2010-01-01

    Animal cell culture technology has advanced significantly over the last few decades and is now generally considered a reliable, robust and relatively mature technology. A range of biotherapeutics are currently synthesized using cell culture methods in large scale manufacturing facilities that produce products for both commercial use and clinical studies. The robust implementation of this technology requires optimization of a number of variables, including (1) cell lines capable of synthesizing the required molecules at high productivities that ensure low operating cost; (2) culture media and bioreactor culture conditions that achieve both the requisite productivity and meet product quality specifications; (3) appropriate on-line and off-line sensors capable of providing information that enhances process control; and (4) good understanding of culture performance at different scales to ensure smooth scale-up. Successful implementation also requires appropriate strategies for process development, scale-up and process characterization and validation that enable robust operation and ensure compliance with current regulations. This review provides an overview of the state-of-the art technology in key aspects of cell culture, e.g., generation of highly productive cell lines and optimization of cell culture process conditions. We also summarize the current thinking on appropriate process development strategies and process advances that might affect process development. PMID:20622510

  18. A corporate product integrity assurance process.

    PubMed

    Weiler, E D; Keener, R

    1991-10-01

    One of the more difficult challenges that confronts the chemical industry throughout the industrialized world is how to effectively manage the various and often diverse regulatory requirements. What follows is a description of a process designed to help with new product introductions. The process is generic and is applicable to almost any corporate environment and structure. PMID:1669968

  19. Dentin bonding agents and resin cements--current status.

    PubMed

    Woolsey, G; O'Mahony, A; Hansen, P A

    2000-01-01

    Contemporary restorative dentistry is a rapidly evolving science which challenges the progressive clinician with a plethora of "new and improved" products. Sound product choices should be couched in the prudent consideration of well conducted in vitro and in vivo product research. This review shall list the most recent product developments in dentin bonding agents (fifth generation agents), resin-containing dental cements and the newest generation of dental cements i.e., resin-ionomer dental cements. PMID:11326526

  20. CITRIC ACID AS A SET RETARDER FOR CALCIUM ALUMINATE PHOSPHATE CEMENTS.

    SciTech Connect

    SUGAMA,T.; BROTHERS, L.E.

    2005-01-01

    Citric acid added as set retarder significantly contributed to enhancing the setting temperature and to extending the thickening time of a calcium aluminate phosphate (CaP) geothermal cement slurry consisting of calcium aluminate cement (CAC) as the base reactant and sodium polyphosphate (NaP) solution as the acid reactant. The set-retarding activity of citric acid was due to the uptake of Ca{sup 2+} ions from the CAC by carboxylic acid groups within the citric acid. This uptake led to the precipitation of a Ca-complexed carboxylate compound as a set-retarding barrier layer on the CAC grains' surfaces. However, this barrier layer was vulnerable to disintegration by the attack of free Ca{sup 2+} ions from CAC, and also to degradation at elevated temperature, thereby promoting the generation of exothermic energy from acid-base reactions between the CAC and NaP after the barrier was broken. The exothermic reaction energy that was promoted in this way minimized the loss in strength of the citric acid-retarded cement. The phase composition assembled in both retarded and non-retarded cements after autoclaving at 180 C encompassed three reaction products, hydroxyapatite (HOAp), hydrogrossular and boehmite, which are responsible for strengthening the autoclaved cement. The first two reaction products were susceptible to reactions with sulfuric acid and sodium sulfate to form crystalline bassanite scale as the corrosion product. The boehmite phase possessed a great resistance to acid and sulfate. Although the bassanite scales clinging to the cement's surfaces were the major factor governing the loss in weight, they served in protecting the cement from further acid- and sulfate-corrosion until their spallation eventually occurred. Nevertheless, the repetitive processes of HOAp and hydrogrossular {yields} bassanite {yields} spallation played an important role in extending the useful lifetime of CaP cement in a low pH environment at 180 C.

  1. Primary Cementing of a Highly Deviated Oil Well

    E-print Network

    Fournier, John J.F.

    Primary Cementing of a Highly Deviated Oil Well by Mariana Carrasco-Teja B.Sc., Instituto Tecnol. The study comes from the primary cementing of highly deviated oil and gas wells. Highly deviated wells are those in which part of the wellbore is nearly horizontal. Primary cementing is a critical process

  2. MULTIMEDIA ASSESSMENT AND ENVIRONMENTAL RESEARCH NEEDS OF THE CEMENT INDUSTRY

    EPA Science Inventory

    This project was initiated to obtain a comprehensive assessment of the cement industry and its environmental research needs. This report contains a profile of the U.S. cement industry; an analysis of the cement manufacturing processes; a discussion of waste stream characteristics...

  3. Early age hydration and pozzolanic reaction in natural zeolite blended cements: Reaction kinetics and products by in situ synchrotron X-ray powder diffraction

    SciTech Connect

    Snellings, R.; Mertens, G.; Cizer, O.; Elsen, J.

    2010-12-15

    The in situ early-age hydration and pozzolanic reaction in cements blended with natural zeolites were investigated by time-resolved synchrotron X-ray powder diffraction with Rietveld quantitative phase analysis. Chabazite and Na-, K-, and Ca-exchanged clinoptilolite materials were mixed with Portland cement in a 3:7 weight ratio and hydrated in situ at 40 {sup o}C. The evolution of phase contents showed that the addition of natural zeolites accelerates the onset of C{sub 3}S hydration and precipitation of CH and AFt. Kinetic analysis of the consumption of C{sub 3}S indicates that the enveloping C-S-H layer is thinner and/or less dense in the presence of alkali-exchanged clinoptilolite pozzolans. The zeolite pozzolanic activity is interpreted to depend on the zeolite exchangeable cation content and on the crystallinity. The addition of natural zeolites alters the structural evolution of the C-S-H product. Longer silicate chains and a lower C/S ratio are deduced from the evolution of the C-S-H b-cell parameter.

  4. Carbon nanotube mass production: principles and processes.

    PubMed

    Zhang, Qiang; Huang, Jia-Qi; Zhao, Meng-Qiang; Qian, Wei-Zhong; Wei, Fei

    2011-07-18

    Our society requires new materials for a sustainable future, and carbon nanotubes (CNTs) are among the most important advanced materials. This Review describes the state-of-the-art of CNT synthesis, with a focus on their mass-production in industry. At the nanoscale, the production of CNTs involves the self-assembly of carbon atoms into a one-dimensional tubular structure. We describe how this synthesis can be achieved on the macroscopic scale in processes akin to the continuous tonne-scale mass production of chemical products in the modern chemical industry. Our overview includes discussions on processing methods for high-purity CNTs, and the handling of heat and mass transfer problems. Manufacturing strategies for agglomerated and aligned single-/multiwalled CNTs are used as examples of the engineering science of CNT production, which includes an understanding of their growth mechanism, agglomeration mechanism, reactor design, and process intensification. We aim to provide guidelines for the production and commercialization of CNTs. Although CNTs can now be produced on the tonne scale, knowledge of the growth mechanism at the atomic scale, the relationship between CNT structure and application, and scale-up of the production of CNTs with specific chirality are still inadequate. A multidisciplinary approach is a prerequisite for the sustainable development of the CNT industry. PMID:21732544

  5. Bottom-up Representation of Industrial Energy Efficiency Technologies in Integrated Assessment Models for the Cement Sector

    E-print Network

    Sathaye, J.

    2011-01-01

    New Generation of Process Optimisation Systems, International Cements New 2200 tpd Seattle Plant Comes on Line. World Cement,Cement Industry Technical Conference XXXIX Conference Record, Institute of Electrical and Electronics Engineers: New

  6. Leach studies on cement-solidified ion exchange resins from decontamination processes at operating nuclear power stations

    SciTech Connect

    McIsaac, C.V.; Akers, D.W.; McConnell, J.W.; Morcos, N.

    1992-08-01

    The effects of varying pH and leachant compositions on the physical stability and leachability of radionuclides and chelating agents were determined for cement-solidified decontamination ion-exchange resin wastes collected from two operating commercial light water reactors. Small scale waste-form specimens were collected during waste solidifications performed at the Brunswick Steam Electric Plant Unit 1 and at the James A. FitzPatrick Nuclear Power Station. The collected specimens were leach tested, and their compressive strength was measured in accordance with the Nuclear Regulatory Commission`s ``Technical Position on Waste Form`` (Revision 1), from the Low-Level Waste Management Branch. Leachates from these studies were analyzed for radionuclides, selected transition metals, and chelating agents to assess the leachability of these waste form constituents. Leachants used for the study were deionized water, simulated seawater, and groundwater compositions similar to those found at Barnwell, South Carolina and Hanford, Washington. Results of this study indicate that initial leachant pH does not affect leachate pH or releases from cement-solidified decontamination ion-exchange resin waste forms. However, differences in leachant composition and the presence of chelating agents may affect the releases of radionuclides and chelating agents. In addition, results from this study indicate that the cumulative releases of radionuclides and chelating agents observed for forms that disintegrated were similar to those for forms that maintained their general physical integrity.

  7. Leach studies on cement-solidified ion exchange resins from decontamination processes at operating nuclear power stations

    SciTech Connect

    McIsaac, C.V.; Akers, D.W.; McConnell, J.W.; Morcos, N.

    1992-01-01

    The effects of varying pH and leachant compositions on the physical stability and leachability of radionuclides and chelating agents were determined for cement-solidified decontamination ion-exchange resin wastes collected from two operating commercial light water reactors. Small scale waste-form specimens were collected during waste solidifications performed at the Brunswick Steam Electric Plant Unit 1 and at the James A. FitzPatrick Nuclear Power Station. The collected specimens were leach tested, and their compressive strength was measured in accordance with the Nuclear Regulatory Commission's Technical Position on Waste Form'' (Revision 1), from the Low-Level Waste Management Branch. Leachates from these studies were analyzed for radionuclides, selected transition metals, and chelating agents to assess the leachability of these waste form constituents. Leachants used for the study were deionized water, simulated seawater, and groundwater compositions similar to those found at Barnwell, South Carolina and Hanford, Washington. Results of this study indicate that initial leachant pH does not affect leachate pH or releases from cement-solidified decontamination ion-exchange resin waste forms. However, differences in leachant composition and the presence of chelating agents may affect the releases of radionuclides and chelating agents. In addition, results from this study indicate that the cumulative releases of radionuclides and chelating agents observed for forms that disintegrated were similar to those for forms that maintained their general physical integrity.

  8. Cement mixing with vibrator

    SciTech Connect

    Allen, T.E.

    1991-07-09

    This patent describes a method of cementing a casing string in a bore hole of a well. It comprises introducing water and dry cement material into a mixing vessel; mixing the water and dry cement material in the mixing vessel to form a cement slurry, the slurry including lumps of the dry cement material, the mixing including steps of: agitating the slurry; and while agitating the slurry, transmitting vibrational energy into the slurry and thereby aiding disintegration and subsequent wetting of the lumps of the dry cement material in the slurry; and pumping the slurry into an annulus between the casing string and the bore hole.

  9. Heterogeneous Glasses and Sustainable Cement

    NASA Astrophysics Data System (ADS)

    Del Gado, Emanuela

    2015-03-01

    Calcium-silicate hydrate (C-S-H) is the main binding agent in cement and concrete. It forms at the beginning of cement hydration, it progressively densifies as cement hardens and is ultimately responsible for the performances of concrete. This hydration product is a cohesive nano-scale heterogeneous glass, whose structure and mechanics are still poorly understood, in spite of its practical importance. I will review some of the open questions for this fascinating material and discuss a statistical physics approach recently developed, which allows us to investigate the structural arrest and solidification under the out-of-equilibrium conditions typical of cement hydration and the role of the nano-scale structure in C-S-H mechanics upon hardening. Our approach unveils how some distinctive features of the kinetics of cement hydration can be related to changes in the morphology of this glassy material and elucidates the role of nano-scale mechanical heterogeneities in the hardened C-S-H.

  10. Cemented implant restoration: A technique for minimizing adverse biologic consequences.

    PubMed

    Galván, Guillermo; Kois, John C; Chaiyabutr, Yada; Kois, Dean

    2015-10-01

    The purpose of this technique was to eliminate excess cement from the implant restoration by using a 2-step cementation process. A custom acrylic resin abutment, a duplicate of the titanium abutment, is fabricated before the restoration is cemented. At cementation, cement is placed inside the restoration, which is placed onto the acrylic resin abutment outside the mouth. The majority of the excess cement from inside the restoration is expressed onto the acrylic resin abutment. The restoration is then placed on the titanium abutment inside the mouth. The result is a minimum amount of excess cement expressed intraorally. This technique minimizes the adverse biological consequences of leaving excess cement beneath implant-supported restorations. PMID:26119018

  11. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Frozen processed food products. 870.111-5...PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a...

  12. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Frozen processed food products. 870.111-5...PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a...

  13. Incinerators and cement kilns face off

    SciTech Connect

    Kim, I.

    1994-04-01

    For the past few years, US incinerators have been at odds with thermal waste processors such as cement kilns. Originally, there was enough room in the industrial waste treatment market for both types of treatment. As waste generators turned to pollution prevention and onsite treatment, however, the volume of waste decreased and its composition changed. Now, each sees the other crowding it out of a tightening market, and the fight between them is growing increasingly bitter. At the center of this battle are the products of alternative thermal processes--for cement kilns, the dust formed after processing, and for other processes, a variety of materials, many of which can be used for construction. Currently, these materials are exempted from regulation under the US Resource Conservation and Recovery Act (RCRA). In addition, the alternative processes offer generators a significant cost advantage over incineration. The question that US regulators are now grappling with is whether these materials are safe enough to justify this preferential treatment. So far, the answer seems to be a qualified yes. The paper discusses these issues.

  14. Policy Options for Encouraging Energy Efficiency Best Practices in Shandong Province's Cement Industry

    E-print Network

    Price, Lynn

    2013-01-01

    for a ball mill, depending on the fineness of the cement. AShandong cement production in 2009 Replacing a ball millcement production capacity 10,000 tonne/year High pressure roller press as pre-grinding to ball mill

  15. Estimates of global, regional, and national annual CO{sub 2} emissions from fossil-fuel burning, hydraulic cement production, and gas flaring: 1950--1992

    SciTech Connect

    Boden, T.A.; Marland, G.; Andres, R.J.

    1995-12-01

    This document describes the compilation, content, and format of the most comprehensive C0{sub 2}-emissions database currently available. The database includes global, regional, and national annual estimates of C0{sub 2} emissions resulting from fossil-fuel burning, cement manufacturing, and gas flaring in oil fields for 1950--92 as well as the energy production, consumption, and trade data used for these estimates. The methods of Marland and Rotty (1983) are used to calculate these emission estimates. For the first time, the methods and data used to calculate CO, emissions from gas flaring are presented. This C0{sub 2}-emissions database is useful for carbon-cycle research, provides estimates of the rate at which fossil-fuel combustion has released C0{sub 2} to the atmosphere, and offers baseline estimates for those countries compiling 1990 C0{sub 2}-emissions inventories.

  16. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2003-10-31

    The objective of this project is to develop an improved ultra- lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report discusses testing that was performed for analyzing the alkali-silica reactivity of ULHS in cement slurries.

  17. Sustainability Analysis for Products and Processes

    EPA Science Inventory

    Sustainability Analysis for Products and Processes Subhas K. Sikdar National Risk Management Research Laboratory United States Environmental protection Agency 26 W. M.L. King Dr. Cincinnati, OH 45237 Sikdar.subhas@epa.gov ABSTRACT Claims of both sustainable and unsu...

  18. Syllables as Processing Units in Handwriting Production

    ERIC Educational Resources Information Center

    Kandel, Sonia; Alvarez, Carlos J.; Vallee, Nathalie

    2006-01-01

    This research focused on the syllable as a processing unit in handwriting. Participants wrote, in uppercase letters, words that had been visually presented. The interletter intervals provide information on the timing of motor production. In Experiment 1, French participants wrote words that shared the initial letters but had different syllable…

  19. Understanding the Term Gifted: Process? Product? Performance?

    ERIC Educational Resources Information Center

    Sloat, Robert S.

    1990-01-01

    A model is presented that views gifted individuals as being process oriented, creative individuals as product oriented, and talented individuals as performance oriented. Approaches to acting that differ based on elements of giftedness, creativity, talent, and combinations thereof are explored. (JDD)

  20. Optimal Control of Raw Timber Production Processes

    E-print Network

    Optimal Control of Raw Timber Production Processes Ivan Kolenka Abstract: This paper demonstrates the possibility of optimal planning and control of timber harvesting activ- ities with mathematical optimization in planning (e.g., optimal control of timber hauling); others have been theoretically validated

  1. Science Is Process, Product, and Perseverance.

    ERIC Educational Resources Information Center

    Jaus, Harold H.

    2002-01-01

    Answers the question, "What is science? with two components: body of knowledge and doing procedure. Points out the pitfalls scientists experience and how these pitfalls are not presented in textbooks, thereby affecting students' understanding and appreciation of science. Explains science as process, product, and perseverance. (YDS)

  2. [Augmentation with PMMA cement].

    PubMed

    Kühn, K-D; Höntzsch, D

    2015-09-01

    Cements based on polymethyl methacrylate (PMMA) can be used without any problem in a variety of clinical augmentations. Cement-related complications in surgical procedures involving PMMA cements, such as embolism, thermal necrosis, toxicity and hypersensitivity, are often due to other causes. Knowledge about the properties of the cement helps the user to safely employ PMMA cements in augmentations. High radio-opacity is required in vertebral body augmentations and this is provided in particular by zirconium dioxide. In vertebral body augmentations, a low benzoyl peroxide (BPO) content can considerably prolong the liquid dough phase. In augmentations with cement fillings in the region of a tumor, a high BPO content can specifically increase the peak temperature of the PMMA cement. In osteosynthetic augmentations with PMMA, necrosis is rare because heat development in the presence of metallic implants is low due to heat conduction via the implant. Larger cement fillings where there is no heat conduction via metal implants can exhibit substantially higher peak temperatures. The flow properties of PMMA cements are of particular importance for the user to allow optimum handling of PMMA cements. In patients with hypersensitivity to antibiotics, there is no need to avoid the use of PMMA as there are sufficient PMMA-based alternatives. The PMMA cements are local drug delivery systems and antibiotics, antiseptics, antimycotics and also cytostatics can be mixed with the cement. Attention must be paid to antagonistic and synergistic effects. PMID:26315391

  3. Process for biodiesel production from Cryptococcus curvatus.

    PubMed

    Thiru, Meikandhan; Sankh, Santosh; Rangaswamy, Vidhya

    2011-11-01

    The objective of the current report is process optimization for economical production of lipids by the well known oleaginous yeast Cryptococcus curvatus and conversion of the lipids to biodiesel. A high cell density fed-batch cultivation on low cost substrate viz. crude glycerol resulted in a dry biomass and oil yield of up to 69 g/L and 48% (w/w), respectively. The process was scaled up easily to 26 L. The oil extraction process was also optimized using environmentally safe solvents. The oil profile indicated a high oleic acid content followed by palmitic acid, stearic acid and linoleic acid. The oil was trans-esterified to biodiesel and thoroughly characterized. This is the first end to end report on production of biodiesel from the C. curvatus oil. PMID:21930373

  4. Distribution of Hg, As and Se in material and flue gas streams from preheater-precalciner cement kilns and vertical shaft cement kilns in China.

    PubMed

    Yan, Dahai; Peng, Zheng; Ding, Qiong; Karstensen, Kåre Helge; Engelsen, Christian J; Li, Li; Ren, Yong; Jiang, Chen

    2015-08-01

    The aim of this study was to evaluate the behavior of Hg, As, and Se in cement production. Two types of cement plants were studied, including the vertical shaft kiln (VSK) and preheater-precalciner kiln (PPK) processes. Determination of Hg, As, and Se in the main material and gas streams were performed. It was found that recycling of particulate matter captured by an air pollution control device caused a significant enrichment of Hg and As inside both processes. The total quantity of Hg entering the process and the quantity emitted to the atmosphere were found to be 10-109 and 6.3-38 mg, respectively, per ton of clinker produced. The average Hg emission was calculated to be around 41% of the total mercury input. The emissions found complied with the European Union (EU) limit and exceeded partly the U.S. limit. Furthermore, it was found that oxidized mercury was the dominant species in the PPK process, whereas the reduced form was dominant in the VSK process, due to the oxidizing and reducing gas conditions, respectively. Regarding the distribution of As and Se, the major amounts were bound to the solid materials, that is, cement clinker and particulate matter. Based on cement production data in China in 2013, the annual emissions of Hg and As were estimated to be in the range of 8.6-52 and 4.1-9.5 tons, respectively. PMID:26037967

  5. The effects of process gas type on the surface condition of high-power diode laser-treated ordinary Portland cement

    NASA Astrophysics Data System (ADS)

    Lawrence, J.; Li, L.

    2001-12-01

    This paper examines the effects of using O 2, Ar and He process gasses during the treatment of the ordinary Portland cement (OPC) surface of concrete with a high-power diode laser (HPDL). The study revealed that, depending on the shield gas used, distinct difference existed in the surface condition of the concrete after HPDL treatment. In particular, the use of O 2 as the shield gas was seen to result in glazes with far fewer microcracks and porosities than those generated with either Ar or He shield gases. Such differences were found to be due to the smaller O 2 gas molecules dissolving molecularly into the open structure of the HPDL-generated glaze on the OPC surface of concrete and react with the glass network to increase the fluidity of the melt. This in turn was also seen to affect the cooling rate and therefore the tendency to generate microcracks.

  6. Principles and applications of cement slurries

    SciTech Connect

    Guillot, D.; Baret, J.F.

    1996-12-31

    The basic principles of oil well cementing are first described together with the main critical engineering constraints encountered during a primary cementing operation, that is, wellbore control, mud displacement, fluid loss control, and gas migration. Then cement slurry properties that are relevant to the process are reviewed and the procedures used to measure these properties are discussed. Particular attention is given to rheological measurements that call be affected by wall slip when losing coaxial cylinder or pipe flow viscometers. This is followed by an overview of the additives that are used to obtained the required cement slurry or set cement properties, like weighting agents/extenders, retarders, dispersants, fluid loss agents, and antisettling agents. Some typical mechanisms of action of these additives are briefly discussed. 30 refs., 23 figs., 2 tabs.

  7. Current Status of Geothermal Well Cement Development

    SciTech Connect

    Kukacka, L. E.

    1981-01-01

    The results of a study made in 1976 indicated that the cements used for well completion deteriorate in the geothermal environments and that the life expectancy of a well, and therefore the economics of geothermal processes, could be improved significantly if better materials were developed. On the basis of this assessment, Brookhaven National Laboratory (BNL) helped the Department of Energy, Division of Geothermal Energy to organize a program to develop materials that meet the estimated design criteria for geothermal well cements. The BNL work involves research on polymer cements and full management of an integrated program involving contract research and industrial participation. The program consists of the following phases: (1) problem definition, (2) cement research and development, (3) property verification, (4) downhole testing, and (5) cementing of demonstration wells.

  8. INVESTIGATION OF THE FORMATION OF A PORTLAND CEMENT PLANT DETACHED PLUME

    EPA Science Inventory

    A gaseous and particulate source emissions sampling program has been conducted at a Portland Cement production plant in Rapid City South Dakota. The study was conducted to determine the cause of the formation of an opaque detached plume from the plants' dry process kiln. The inst...

  9. Literature survey on cements for remediation of deformed casing in geothermal wells

    SciTech Connect

    Allan, M.L.; Philippacopoulos, A.J.

    1998-12-31

    Brookhaven National Laboratory was requested to conduct a literature survey for the best available cement to use in the proposed casing patch as part of the Geothermal Drilling Organization (GDO) project on remediation of deformed casings. A total of 50 wells have been identified with deformed production casing in Unocal`s portion of The Geysers geothermal field. A procedure to address the casing deformation and avoid abandonment of these wells has been developed as described in the Geysers Deformed Casing Remediation Proposal. The proposed remediation procedure involves isolation of the zone of interest with an inflatable packer, milling the deformed casing and cementing a 7 inch diameter liner to extend approximately 100 ft above and 100 ft below the milled zone. During the milling operation it is possible that the original cement and surrounding formation may slough away. In order to specify a suitable cement formulation for the casing patch it is first necessary to identify and understand the deformation mechanism/s operating in The Geysers field. Subsequently, the required cement mechanical properties to withstand further deformation of the repaired system must be defined. From this information it can be determined whether available cement formulations meet these requirements. In addition to The Geysers, other geothermal fields are at possible risk of casing deformation due to subsidence, seismic activity, lateral and vertical formation movement or other processes. Therefore, the proposed remediation procedure may have applications in other fields.

  10. The suitability of a supersulfated cement for nuclear waste immobilisation

    NASA Astrophysics Data System (ADS)

    Collier, N. C.; Milestone, N. B.; Gordon, L. E.; Ko, S.-C.

    2014-09-01

    Composite cements based on ordinary Portland cement are used in the UK as immobilisation matrices for low and intermediate level nuclear wastes. However, the high pore solution pH causes corrosion of some metallic wastes and undesirable expansive reactions, which has led to alternative cementing systems being examined. We have investigated the physical, chemical and microstructural properties of a supersulfated cement in order to determine its applicability for use in nuclear waste encapsulation. The hardened supersulfated cement paste appeared to have properties desirable for use in producing encapsulation matrices, but the high powder specific surface resulted in a matrix with high porosity. Ettringite and calcium silicate hydrate were the main phases formed in the hardened cement paste and anhydrite was present in excess. The maximum rate of heat output during hydration of the supersulfated cement paste was slightly higher than that of a 9:1 blastfurnace slag:ordinary Portland cement paste commonly used by the UK nuclear waste processing industry, although the total heat output of the supersulfated cement paste was lower. The pH was also significantly lower in the supersulfated cement paste. Aluminium hydroxide was formed on the surface of aluminium metal encapsulated in the cement paste and ettringite was detected between the aluminium hydroxide and the hardened cement paste.

  11. Comparative assessment of TRU waste forms and processes. Volume I. Waste form and process evaluations

    SciTech Connect

    Ross, W.A.; Lokken, R.O.; May, R.P.; Roberts, F.P.; Timmerman, C.L.; Treat, R.L.; Westsik, J.H. Jr.

    1982-09-01

    This study provides an assesses seven waste forms and eight processes for immobilizing transuranic (TRU) wastes. The waste forms considered are cast cement, cold-pressed cement, FUETAP (formed under elevated temperature and pressure) cement, borosilicate glass, aluminosilicate glass, basalt glass-ceramic, and cold-pressed and sintered silicate ceramic. The waste-immobilization processes considered are in-can glass melting, joule-heated glass melting, glass marble forming, cement casting, cement cold-pressing, FUETAP cement processing, ceramic cold-pressing and sintering, basalt glass-ceramic processing. Properties considered included gas generation, chemical durability, mechanical strength, thermal stability, and radiation stability. The ceramic products demonstrated the best properties, except for plutonium release during leaching. The glass and ceramic products had similar properties. The cement products generally had poorer properties than the other forms, except for plutonium release during leaching. Calculations of the Pu release indicated that the waste forms met the proposed NRC release rate limit of 1 part in 10/sup 5/ per year in most test conditions. The cast-cement process had the lowest processing cost, followed closely by the cold-pressed and FUETAP cement processes. Joule-heated glass melting had the lower cost of the glass processes. In-can melting in a high-quality canister had the highest cost, and cold-pressed and sintered ceramic the second highest. Labor and canister costs for in-can melting were identified. The major contributor to costs of disposing of TRU wastes in a defense waste repository is waste processing costs. Repository costs could become the dominant cost for disposing of TRU wastes in a commercial repository. It is recommended that cast and FUETAP cement and borosilicate glass waste-form systems be considered. 13 figures, 16 tables.

  12. INVESTIGATIONS ON HYDRAULIC CEMENTS FROM SPENT OIL SHALE

    SciTech Connect

    Mehta, P.K.; Persoff, P.

    1980-04-01

    A process for making hydraulic cements from spent oil shale is described in this paper. Inexpensive cement is needed to grout abandoned in-situ retorts of spent shale for subsidence control, mitigation of leaching, and strengthening the retorted mass in order to recover oil from adjacent pillars of raw shale. A hydraulic cement was produced by heating a 1:1 mixture of Lurgi spent shale and CaCO{sub 3} at 1000 C for one hour. This cement would be less expensive than ordinary portland cement and is expected to fulfill the above requirements.

  13. Power plant fly ash as a resource for alumina and cement

    SciTech Connect

    Murtha, M.J.; Burnet, G.

    1980-01-01

    A sinter process has been developed to form soluble aluminate compounds from mixtures of fly ash, limestone, and soda ash. The aluminates are extracted, treated to remove silicates, and precipitated; the precipitate is calcined to metallurgical grade alumina. The extract residue shows promise as a raw material for the production of Portland cement. Process economics are presented, and the effects of alumina and silica contents of the fly ash, sintering temperatures and time, and sales credits for by-products are discussed.

  14. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2001-04-15

    The objective of this project is to develop an improved ultra-lightweight cement using ultralight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Problems and Task 3: Test Ultra-Lightweight Cements. Results reported this quarter include a review and summary of Halliburton Energy Services (HES) and BJ Services historical performance data for lightweight cement applications. These data are analyzed and compared to ULHS cement and foamed cement performances. Similar data is expected from Schlumberger, and an analysis of this data will be completed in the following phases of the project. Quality control testing of materials used to formulate ULHS cements in the laboratory was completed to establish baseline material performance standards. A testing protocol was developed employing standard procedures as well as procedures tailored to evaluate ULHS and foamed cement. This protocol is presented and discussed. Results of further testing of ULHS cements are presented along with an analysis to establish cement performance design criteria to be used during the remainder of the project. Finally, a list of relevant literature on lightweight cement performance is compiled for review during the next quarter.

  15. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2002-04-29

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report includes results from laboratory testing of ULHS systems along with other lightweight cement systems, including foamed and sodium silicate slurries. During this project quarter, comparison studies of the three cement systems examined several properties: tensile strength, Young's modulus, and shear bond. Testing to determine the effect of temperature cycling on the shear bond properties of the cement systems was also conducted. In addition, the stress-strain behavior of the cement types was studied. This report discusses a software program that is being developed to help design ULHS cements and foamed cements.

  16. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2002-10-31

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report includes results from laboratory testing of ULHS systems along with other lightweight cement systems, including foamed and sodium silicate slurries. During this project quarter, a comparison study of the three cement systems examined the effect that cement drillout has on the three cement systems. Testing to determine the effect of pressure cycling on the shear bond properties of the cement systems was also conducted. This report discusses testing that will be performed for analyzing the alkali-silica reactivity of ULHS in cement slurries, as well as the results of Field Tests 1 and 2.

  17. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2001-07-18

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Issues, Task 2: Review Russian Ultra-Lightweight Cement Literature, Task 3: Test Ultra-Lightweight Cements, and Task 8: Develop Field ULHS Cement Blending and Mixing Techniques. Results reported this quarter include: preliminary findings from a literature review focusing on problems associated with ultra-lightweight cements; summary of pertinent information from Russian ultra-lightweight cement literature review; laboratory tests comparing ULHS slurries to foamed slurries and sodium silicate slurries for two different applications; and initial laboratory studies with ULHS in preparation for a field job.

  18. Mineral of the month: cement

    USGS Publications Warehouse

    van Oss, Hendrik G.

    2006-01-01

    Hydraulic cement is a virtually ubiquitous construction material that, when mixed with water, serves as the binder in concrete and most mortars. Only about 13 percent of concrete by weight is cement (the rest being water and aggregates), but the cement contributes all of the concrete’s compressional strength. The term “hydraulic” refers to the cement’s ability to set and harden underwater through the hydration of the cement’s components.

  19. Multiphase Flow Modeling of Biofuel Production Processes

    SciTech Connect

    D. Gaston; D. P. Guillen; J. Tester

    2011-06-01

    As part of the Idaho National Laboratory's (INL's) Secure Energy Initiative, the INL is performing research in areas that are vital to ensuring clean, secure energy supplies for the future. The INL Hybrid Energy Systems Testing (HYTEST) Laboratory is being established to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. HYTEST involves producing liquid fuels in a Hybrid Energy System (HES) by integrating carbon-based (i.e., bio-mass, oil-shale, etc.) with non-carbon based energy sources (i.e., wind energy, hydro, geothermal, nuclear, etc.). Advances in process development, control and modeling are the unifying vision for HES. This paper describes new modeling tools and methodologies to simulate advanced energy processes. Needs are emerging that require advanced computational modeling of multiphase reacting systems in the energy arena, driven by the 2007 Energy Independence and Security Act, which requires production of 36 billion gal/yr of biofuels by 2022, with 21 billion gal of this as advanced biofuels. Advanced biofuels derived from microalgal biomass have the potential to help achieve the 21 billion gal mandate, as well as reduce greenhouse gas emissions. Production of biofuels from microalgae is receiving considerable interest due to their potentially high oil yields (around 600 gal/acre). Microalgae have a high lipid content (up to 50%) and grow 10 to 100 times faster than terrestrial plants. The use of environmentally friendly alternatives to solvents and reagents commonly employed in reaction and phase separation processes is being explored. This is accomplished through the use of hydrothermal technologies, which are chemical and physical transformations in high-temperature (200-600 C), high-pressure (5-40 MPa) liquid or supercritical water. Figure 1 shows a simplified diagram of the production of biofuels from algae. Hydrothermal processing has significant advantages over other biomass processing methods with respect to separations. These 'green' alternatives employ a hybrid medium that, when operated supercritically, offers the prospect of tunable physicochemical properties. Solubility can be rapidly altered and phases partitioned selectively to precipitate or dissolve certain components by altering temperature or pressure in the near-critical region. The ability to tune the solvation properties of water in the highly compressible near-critical region facilitates partitioning of products or by-products into separate phases to separate and purify products. Since most challenges related to lipid extraction are associated with the industrial scale-up of integrated extraction systems, the new modeling capability offers the prospect of addressing previously untenable scaling issues.

  20. Phosphate-bonded calcium aluminate cements

    DOEpatents

    Sugama, T.

    1993-09-21

    A method is described for making a rapid-setting phosphate-bonded cementitious material. A powdered aluminous cement is mixed with an aqueous solution of ammonium phosphate. The mixture is allowed to set to form an amorphous cementitious material which also may be hydrothermally treated at a temperature of from about 120 C to about 300 C to form a crystal-containing phosphate-bonded material. Also described are the cementitious products of this method and the cement composition which includes aluminous cement and ammonium polyphosphate. 10 figures.

  1. Phosphate-bonded calcium aluminate cements

    DOEpatents

    Sugama, Toshifumi (Mastic Beach, NY)

    1993-01-01

    A method is described for making a rapid-setting phosphate-bonded cementitious material. A powdered aluminous cement is mixed with an aqueous solution of ammonium phosphate. The mixture is allowed to set to form an amorphous cementitious material which also may be hydrothermally treated at a temperature of from about 120.degree. C. to about 300.degree. C. to form a crystal-containing phosphate-bonded material. Also described are the cementitious products of this method and the cement composition which includes aluminous cement and ammonium polyphosphate.

  2. Processes controlling precipitation of carbonate cement and dissolution of silica in reef and near-reef settings

    NASA Astrophysics Data System (ADS)

    Epstein, Samuel A.; Friedman, Gerald M.

    1982-11-01

    Carbonate cementation in the surface layer of reefs and beachrock eliminates porosity and partially replaces detrital quartz grains. The uptake and release of CO 2 by photosynthesis and respiration in reef communities cause a shift in the carbonate buffer system of seawater. Field studies and experimentation simulating the natural settings show minimum values of CO 2 (1.9 mmoles 1 -1) and HCO 3- (2.4 meq 1 -1) in association with maximum values of pH (9.8) and O 2 (> 100% oxygen saturation) in waters covering corals and algae prior to sunset. The converse is true for these variables prior to sunrise, when minimum values of pH (7.6) and O 2 (<66% oxygen saturation) occur with maximum values of CO 2 (2.7 mmoles 1 -1) and HCO 3- (2.7 meq 1 -1). Experimental tanks containing plain seawater showed almost no diurnal variability in pH (a constant 7.5-7.6) or O 2 (80-90% oxygen saturation) measurements. Seawater adjacent to reef biomass, with elevated pH and supersaturated with calcium carbonate, is periodically pumped into the underlying reef and beach sediments due to pressure-buildups between the reef framework or algal zones and open waters. Carbonate precipitation and quartz dissolution follow. As the system equilibrates, pH values progressively decrease.

  3. Optical evaluation on the setting of cement paste

    NASA Astrophysics Data System (ADS)

    De León Martínez, H. A.; Bernal, J. J. Soto; González Mota, R.; Rosales-Candelas, I.

    2015-01-01

    In the construction area, one of the most widely used cement is the CPC 30R, it is a hydraulic binder consisting of CaO, SiO2, Al2O3 and Fe2O3, when mixed with water forms cement pastes and its four crystallographic phases start to hydrate. The diffuse reflection on cement paste can give an indication of the behaviour on optical properties on the hydration of the cement and early formation products. In this study, Portland cement (CPC) pastes were prepared with 0.45 a water to cement ratio (w/c). This work is aimed to evaluate the optical properties of cement pastes on the hydration reaction during the first 24 hours by measuring the intensity of diffuse reflection changes.

  4. Development of an Improved Cement for Geothermal Wells

    SciTech Connect

    Trabits, George

    2015-04-20

    After an oil, gas, or geothermal production well has been drilled, the well must be stabilized with a casing (sections of steel pipe that are joined together) in order to prevent the walls of the well from collapsing. The gap between the casing and the walls of the well is filled with cement, which locks the casing into place. The casing and cementing of geothermal wells is complicated by the harsh conditions of high temperature, high pressure, and a chemical environment (brines with high concentrations of carbon dioxide and sulfuric acid) that degrades conventional Portland cement. During the 1990s and early 2000s, the U.S. Department of Energy’s Geothermal Technologies Office (GTO) provided support for the development of fly-ash-modified calcium aluminate phosphate (CaP) cement, which offers improved resistance to degradation compared with conventional cement. However, the use of CaP cements involves some operational constraints that can increase the cost and complexity of well cementing. In some cases, CaP cements are incompatible with chemical additives that are commonly used to adjust cement setting time. Care must also be taken to ensure that CaP cements do not become contaminated with leftover conventional cement in pumping equipment used in conventional well cementing. With assistance from GTO, Trabits Group, LLC has developed a zeolite-containing cement that performs well in harsh geothermal conditions (thermal stability at temperatures of up to 300°C and resistance to carbonation) and is easy to use (can be easily adjusted with additives and eliminates the need to “sterilize” pumping equipment as with CaP cements). This combination of properties reduces the complexity/cost of well cementing, which will help enable the widespread development of geothermal energy in the United States.

  5. The contemporary cement cycle of the United States

    USGS Publications Warehouse

    Kapur, A.; Van Oss, H. G.; Keoleian, G.; Kesler, S.E.; Kendall, A.

    2009-01-01

    A country-level stock and flow model for cement, an important construction material, was developed based on a material flow analysis framework. Using this model, the contemporary cement cycle of the United States was constructed by analyzing production, import, and export data for different stages of the cement cycle. The United States currently supplies approximately 80% of its cement consumption through domestic production and the rest is imported. The average annual net addition of in-use new cement stock over the period 2000-2004 was approximately 83 million metric tons and amounts to 2.3 tons per capita of concrete. Nonfuel carbon dioxide emissions (42 million metric tons per year) from the calcination phase of cement manufacture account for 62% of the total 68 million tons per year of cement production residues. The end-of-life cement discards are estimated to be 33 million metric tons per year, of which between 30% and 80% is recycled. A significant portion of the infrastructure in the United States is reaching the end of its useful life and will need to be replaced or rehabilitated; this could require far more cement than might be expected from economic forecasts of demand for cement. ?? 2009 Springer Japan.

  6. Beta-Product Poisson-Dirichlet Processes

    E-print Network

    Bassetti, Federico; Leisen, Fabrizio

    2011-01-01

    Time series data may exhibit clustering over time and, in a multiple time series context, the clustering behavior may differ across the series. This paper is motivated by the Bayesian non--parametric modeling of the dependence between the clustering structures and the distributions of different time series. We follow a Dirichlet process mixture approach and introduce a new class of multivariate dependent Dirichlet processes (DDP). The proposed DDP are represented in terms of vector of stick-breaking processes with dependent weights. The weights are beta random vectors that determine different and dependent clustering effects along the dimension of the DDP vector. We discuss some theoretical properties and provide an efficient Monte Carlo Markov Chain algorithm for posterior computation. The effectiveness of the method is illustrated with a simulation study and an application to the United States and the European Union industrial production indexes.

  7. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2001-01-15

    The objective of this project is to develop an improved ultra-lightweigh cement using ultralight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Problems, Task 2: Review Russian Ultra-Lightweight Cement Literature, and Task 3: Test Ultra-Lightweight Cements. Results reported this quarter include a review and summary surface pipe and intermediate casing cementing conditions historically encountered in the US and establishment of average design conditions for ULHS cements. Russian literature concerning development and use of ultra-lightweight cements employing either nitrogen or ULHS was reviewed, and a summary is presented. Quality control testing of materials used to formulate ULHS cements in the laboratory was conducted to establish baseline material performance standards. A testing protocol was developed employing standard procedures as well as procedures tailored to evaluate ULHS. This protocol is presented and discussed. finally, results of initial testing of ULHS cements is presented along with analysis to establish cement performance design criteria to be used during the remainder of the project.

  8. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 false Approval of labeling for egg products processed in exempted egg products processing plants. 590.680 Section...AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND...

  9. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 false Approval of labeling for egg products processed in exempted egg products processing plants. 590.680 Section...AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND...

  10. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 false Approval of labeling for egg products processed in exempted egg products processing plants. 590.680 Section...AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND...

  11. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 false Approval of labeling for egg products processed in exempted egg products processing plants. 590.680 Section...AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND...

  12. Evaluation of a new 2-paste glass ionomer cement.

    PubMed

    Komori, Akira; Kojima, Iori

    2003-06-01

    A new 2-paste resin-reinforced glass ionomer cement, Fuji Ortho Band Paste Pak (GC Corporation, Tokyo, Japan), for the placement of orthodontic bands, has been developed for easier handling. The aim of this study was to compare the fluoride release and uptake characteristics of this cement with that of 3 others commonly used to cement orthodontic bands: a conventional resin-reinforced glass ionomer cement, a polyacid-modified composite resin, and a conventional glass ionomer cement. Fluoride release was measured during a 28-day period. After the measurement on day 28, experimental samples were exposed to 1000 ppm sodium fluoride solution for 5 minutes, and fluoride release was then measured for 7 days. Initially, the new 2-paste resin-reinforced glass ionomer cement released the greatest amount of fluoride; the polyacid-modified composite resin released the least initially, and it continued to show the lowest values throughout the study. The fluoride uptake and release values of the new 2-paste resin-reinforced glass ionomer cement were statistically significantly higher than those of the conventional resin-reinforced glass ionomer cement or the conventional glass ionomer cement. The new 2-paste resin-reinforced glass ionomer cement might be a good alternative to conventional products for cementing orthodontic bands. PMID:12806344

  13. Horizontal wells pose cementing challenges

    SciTech Connect

    1996-07-01

    Successful cementing of horizontal wells depends on many factors such as drilling fluid properties, casing centralization, displacement mechanics, cement-mud spacer design and cement slurry properties. Finally, proper evaluation is essential to determine the success or failure of a horizontal casing cement job. The paper discusses displacement mechanics of the drilling fluid and cuttings and cement rheology.

  14. In situ vitrification: Process and products

    SciTech Connect

    Kindle, C.; Koegler, S.

    1991-06-01

    In situ vitrification (ISV) is an electrically powered thermal treatment process that converts soil into a chemically inert and stable glass and crystalline product. It is similar in concept to bringing a simplified glass manufacturing process to a site and operating it in the ground, using the soil as a glass feed stock. Gaseous emissions are contained, scrubbed, and filtered. When the process is completed, the molten volume cools producing a block of glass and crystalline material that resembles natural obsidian commingled with crystalline phases. The product passes US Environmental Protection Agency (EPA) leach resistance tests, and it can be classified as nonhazardous from a chemical hazard perspective. ISV was developed by the Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE) for application to contaminated soils. It is also being adapted for applications to buried waste, underground tanks, and liquid seepage sites. ISV's then-year development period has included tests on many different site conditions. As of January 1991 there have been 74 tests using PNL's ISV equipment; these tests have ranged from technology development tests using nonhazardous conditions to hazardous and radioactive tests. 2 refs., 6 figs., 7 tabs.

  15. Determining the water-cement ratio, cement content, water content and degree of hydration of hardened cement paste: Method development and validation on paste samples

    SciTech Connect

    Wong, H.S. Buenfeld, N.R.

    2009-10-15

    We propose a new method to estimate the initial cement content, water content and free water/cement ratio (w/c) of hardened cement-based materials made with Portland cements that have unknown mixture proportions and degree of hydration. This method first quantifies the composition of the hardened cement paste, i.e. the volumetric fractions of capillary pores, hydration products and unreacted cement, using high-resolution field emission scanning electron microscopy (FE-SEM) in the backscattered electron (BSE) mode and image analysis. From the obtained data and the volumetric increase of solids during cement hydration, we compute the initial free water content and cement content, hence the free w/c ratio. The same method can also be used to calculate the degree of hydration. The proposed method has the advantage that it is quantitative and does not require comparison with calibration graphs or reference samples made with the same materials and cured to the same degree of hydration as the tested sample. This paper reports the development, assumptions and limitations of the proposed method, and preliminary results from Portland cement pastes with a range of w/c ratios (0.25-0.50) and curing ages (3-90 days). We also discuss the extension of the technique to mortars and concretes, and samples made with blended cements.

  16. Aluminum-rich belite sulfoaluminate cements: Clinkering and early age hydration

    SciTech Connect

    Martin-Sedeno, M. Carmen; Cuberos, Antonio J.M.; De la Torre, Angeles G.; Alvarez-Pinazo, Gema; Ordonez, Luis M.; Gateshki, Milen; Aranda, Miguel A.G.

    2010-03-15

    Belite sulfoaluminate (BSA) cements have been proposed as environmentally friendly building materials, as their production may release up to 35% less CO{sub 2} into the atmosphere when compared to ordinary Portland cements. Here, we discuss the laboratory production of three aluminum-rich BSA clinkers with nominal mineralogical compositions in the range C{sub 2}S (50-60%), C{sub 4}A{sub 3}$ (20-30%), CA (10%) and C{sub 12}A{sub 7} (10%). Using thermogravimetry, differential thermal analysis, high temperature microscopy, and X-ray powder diffraction with Rietveld quantitative phase analysis, we found that burning for 15 min at 1350 deg. C was the optimal procedure, in these experimental conditions, for obtaining the highest amount of C{sub 4}A{sub 3}$, i.e. a value as close as possible to the nominal composition. Under these experimental conditions, three different BSA clinkers, nominally with 20, 30 and 30 wt.% of C{sub 4}A{sub 3}$, had 19.6, 27.1 and 27.7 wt.%, C{sub 4}A{sub 3}$ respectively, as determined by Rietveld analysis. We also studied the complex hydration process of BSA cements prepared by mixing BSA clinkers and gypsum. We present a methodology to establish the phase assemblage evolution of BSA cement pastes with time, including amorphous phases and free water. The methodology is based on Rietveld quantitative phase analysis of synchrotron and laboratory X-ray powder diffraction data coupled with chemical constraints. A parallel calorimetric study is also reported. It is shown that the beta-C{sub 2}S phase is more reactive in aluminum-rich BSA cements than in standard belite cements. On the other hand, C{sub 4}A{sub 3}$ reacts faster than the belite phases. The gypsum ratio in the cement is also shown to be an important factor in the phase evolution.

  17. Crushed cement concrete substitution for construction aggregates; a materials flow analysis

    USGS Publications Warehouse

    Kelly, Thomas

    1998-01-01

    An analysis of the substitution of crushed cement concrete for natural construction aggregates is performed by using a materials flow diagram that tracks all material flows into and out of the cement concrete portion of the products made with cement concrete: highways, roads, and buildings. Crushed cement concrete is only one of the materials flowing into these products, and the amount of crushed cement concrete substituted influences the amount of other materials in the flow. Factors such as availability and transportation costs, as well as physical properties, that can affect stability and finishability, influence whether crushed cement concrete or construction aggregates should be used or predominate for a particular end use.

  18. Reducing CO2-Emission by using Eco-Cements

    NASA Astrophysics Data System (ADS)

    Voit, K.; Bergmeister, K.; Janotka, I.

    2012-04-01

    CO2 concentration in the air is rising constantly. Globally, cement companies are emitting nearly two billion tonnes/year of CO2 (or around 6 to 7 % of the planet's total CO2 emissions) by producing portland cement clinker. At this pace, by 2025 the cement industry will be emitting CO2 at a rate of 3.5 billion tones/year causing enormous environmental damage (Shi et al., 2011; Janotka et al., 2012). At the dawn of the industrial revolution in the mid-eighteenth century the concentration of CO2 was at a level of ca. 280 ppm. 200 years later at the time of World War II the CO2 level had risen to 310 ppm what results in a rate of increase of 0,15 ppm per year for that period (Shi et al., 2011). In November 2011 the CO2 concentration reached a value of 391 ppm (NOAA Earth System Research Laboratory, 2011), a rise of ca. 81 ppm in 66 years and an increased rate of around 1,2 ppm/year respectively. In the same period cement production in tons of cement has multiplied by a factor of ca. 62 (Kelly & Oss, US Geological Survey, 2010). Thus new CO2-saving eco-cement types are gaining in importance. In these cement types the energy-consuming portland cement clinker is partially replaced by latent hydraulic additives such as blast furnace slag, fly ash or zeolite. These hydraulic additives do not need to be fired in the rotary furnace. They ony need to be pulverized to the required grain size and added to the ground portland cement clinker. Hence energy is saved by skipping the engery-consuming firing process, in addition there is no CO2-degassing as there is in the case of lime burning. Therefore a research project between Austria and Slovakia, funded by the EU (Project ENVIZEO), was initiated in 2010. The main goal of this project is to develop new CEM V eco-types of cements and certificate them for common usage. CEM V is a portland clinker saving cement kind that allows the reduction of clinker to a proportion of 40-64% for CEM V/A and 20-39% for CEM V/B respectively by the input of slag sands, puzzolanes and fly ash (according to standard EN 197-1). In this context four new CEM V kinds have been created, two Austrian types based on slag and fly ash, and two Slovak types, one based on slag and fly ash, the other on slag and natural pozzolana. The pozzolana consist of zeolite of clinoptilolite type that is gained from a Slovak deposit.

  19. Power Ultrasound to Process Dairy Products

    NASA Astrophysics Data System (ADS)

    Bermúdez-Aguirre, Daniela; Barbosa-Cánovas, Gustavo V.

    Conventional methods of pasteurizing milk involve the use of heat regardless of treatment (batch, high temperature short time - HTST or ultra high temperature - UHT sterilization), and the quality of the milk is affected because of the use of high temperatures. Consequences of thermal treatment are a decrease in nutritional properties through the destruction of vitamins or denaturation of proteins, and sometimes the flavor of milk is undesirably changed. These changes are produced at the same time that the goal of the pasteurization process is achieved, which is to have a microbiological safe product, free of pathogenic bacteria, and to reduce the load of deteriorative microorganisms and enzymes, resulting in a product with a longer storage life.

  20. Hydrometallurgical process for the production of beryllium

    SciTech Connect

    Copenhafer, W.C.

    1988-03-08

    A hydrometallurgical process for producing solid beryllium hydroxide from an ore containing a beryllium silicate mineral is described which comprises: (a) leaching the ore by simultaneously contacting with effective amounts of a concentrated caustic solution and lime or lime hydrate, with agitation in a closed reactor at elevated temperature and autogenous pressure, until a slurry is formed containing dissolved beryllium hydroxide and by-product solids comprising waste gangue and calcium-sodium silicates; (b) reducing the pressure to about one atmosphere and maintaining the temperature below the boiling point of the caustic solution; (c) separating the by-product solids from the slurry to leave a pregnant leach liquor; (d) diluting and heating the pregnant leach liquor to precipitate the beryllium hydroxide and to leave a mother liquor containing caustic; and (e) separating the beryllium hydroxide.

  1. Processing of Spent Ion Exchange Resins in a Rotary Calciner - 12212

    SciTech Connect

    Kascheev, Vladimir; Musatov, Nikolay

    2012-07-01

    Processing Russian nuclear ion exchange resin KU-2 using a 'Rotary' calciner was conducted. The resulting product is a dry free flowing powder (moisture content 3 wt.%, Angle of repose of ? 20 deg.). Compared with the original exchange resin the volume of the final product is about 3 times less.. Rotary calciner product can be stored in metal drums or in special reinforced concrete cubicles. After thermal treatment in a rotary calciner, the spent resin product can be solidified in cement yielding the following attributes: - The cemented waste is only a 35% increase over the volume of powder product; - The volume of cement calciner product is almost 9 times less (8.7) than the volume of cement solidified resin; - The mechanical strength of cemented calciner product meets the radioactive waste regulations in Russia. (authors)

  2. Soft X-ray Microscopy of Green Cements

    SciTech Connect

    Monteiro, P. J. M.; Mancio, M.; Chae, R.; Ha, J.; Kirchheim, A. P.; Fischer, P.; Tyliszczak, T.

    2011-09-09

    The present status of the cement and concrete industry is not sustainable. The production of Portland cement is responsible for 7% of the CO{sub 2} emissions in the world and existing reinforced concrete infrastructure is deteriorating at a fast pace. The change in the existing technology requires new developments in our understanding of the nanostructure of hydration products and the complex deterioration reactions. We have been developing an elaborate research program to advance the existing cement and concrete science by characterizing its nanostructure by synchrotron radiation. A new generation of green cements is being studied using high-resolution soft x-ray microscopy at the nano-level.

  3. Soft X-ray Microscopy of Green Cements

    NASA Astrophysics Data System (ADS)

    Monteiro, P. J. M.; Mancio, M.; Kirchheim, A. P.; Chae, R.; Ha, J.; Fischer, P.; Tyliszczak, T.

    2011-09-01

    The present status of the cement and concrete industry is not sustainable. The production of Portland cement is responsible for 7% of the CO2 emissions in the world and existing reinforced concrete infrastructure is deteriorating at a fast pace. The change in the existing technology requires new developments in our understanding of the nanostructure of hydration products and the complex deterioration reactions. We have been developing an elaborate research program to advance the existing cement and concrete science by characterizing its nanostructure by synchrotron radiation. A new generation of green cements is being studied using high-resolution soft x-ray microscopy at the nano-level.

  4. Improvement of casing cementation of deep and ultradeep wells. Part 2: Oilfield cements and cement additives

    NASA Astrophysics Data System (ADS)

    Arens, K. H.; Akstinat, M.

    1982-07-01

    Oilfield cements and cement additives were investigated in order to improve the casing cementation of deep and ultradeep wells. Characterization and evaluation of the main oil field cements commercially available were studied. The testing was carried out according to American Petroleum Institute API standards and nonstandardized test methods (dynamic modulus of elasticity, expansion/shrinkage), especially the rheology, thickening time and the influence of pressure, temperature and water-cement ratio, were considered. The main emphasis in the field of cement additives was on the evaluation of cement retarders for high temperatures, accelerators, and additives for cement expansion. Furthermore oil field cements were tested, and their properties are described.

  5. Effect of Mineral Trioxide Aggregate, Calcium-Enriched Mixture Cement and Mineral Trioxide Aggregate with Disodium Hydrogen Phosphate on BMP-2 Production

    PubMed Central

    Ghasemi, Negin; Rahimi, Saeed; Lotfi, Mehrdad; Solaimanirad, Jafar; Shahi, Shahriar; Shafaie, Hajar; Salem Milani, Amin; Shakuie, Sahar; Zand, Vahid; Abdolrahimi, Majid

    2014-01-01

    Introduction: One of the hypotheses regarding the calcification induction by mineral trioxide aggregate (MTA) is the involvement of transforming growth factor-Beta (TGF-?) super family. Calcium-enriched mixture (CEM) cement is one of the endodontic biomaterials with clinical applications similar to MTA. The aim of the present in vitro study was to compare the induction of bone morphogenic protein-2 (BMP-2) by a combination of disodium hydrogen phosphate (DSHP) and tooth colored ProRoot MTA (WMTA), to that of CEM cement and WMTA. Methods and Materials: Human gingival fibroblasts (HGFs) were obtained from the attached gingiva of human premolars. HGFs were cultured in Dulbecco’s Modified Eagle’s medium, supplemented with 10% fetal calf serum, penicillin, and streptomycin. Cells in groups 1, 2 and 3 were exposed to WMTA, CEM and WMTA+DSHP discs, respectively. The fourth group served as the control. After 72 h of exposure, HGF viability was determined by Mosmann’s tetrazolium toxicity (MTT) assay. BMP-2 levels in cell-free culture media were determined by enzyme-linked immunosorbent assay (ELISA). Statistical analysis was performed using the one-way ANOVA, followed by the post hoc Games-Howell test for BMP-2 and post hoc Tukey’s test for the results of MTT assay. Results: Cellular viability was significantly higher in group 3 compared to the other groups (P<0.05); however, CEM and WMTA did not exhibit significant differences (P=0.08). The control group exhibited significantly higher cellular viability in comparison to the other groups of the study (P<0.05). The highest and lowest protein production rates were observed in the WMTA (3167±274.46 pg/mL) and WMTA+DSHP (1796±839.49 pg/mL) groups, respectively. There were no significant differences between the control, WMTA and CEM groups (P>0.05). Conclusion: WMTA and CEM did not exhibit any significant differences in terms of inducing BMP-2 production; however, incorporation of DSHP into WMTA resulted in a decrease in the induction of this protein. PMID:25031598

  6. Cyclic thermodynamic processes and entropy production

    E-print Network

    Walid K. Abou Salem; Juerg Froehlich

    2006-04-23

    We study the time evolution of a periodically driven quantum-mechanical system coupled to several reserviors of free fermions at different temperatures. This is a paradigm of a cyclic thermodynamic process. We introduce the notion of a Floquet Liouvillean as the generator of the dynamics on an extended Hilbert space. We show that the time-periodic state to which the true state of the coupled system converges after very many periods corresponds to a zero-energy resonance of the Floquet Liouvillean. We then show that the entropy production per cycle is (strictly) positive, a property that implies Carnot's formulation of the second law of thermodynamics.

  7. Process for production of a metal hydride

    DOEpatents

    Allen, Nathan Tait; Butterick, III, Robert; Chin, Arthur Achhing; Millar, Dean Michael; Molzahn, David Craig

    2014-08-12

    A process for production of a metal hydride compound MH.sub.x, wherein x is one or two and M is an alkali metal, Be or Mg. The process comprises combining a compound of formula (R.sup.1O).sub.xM with aluminum, hydrogen and at least one metal selected from among titanium, zirconium, hafnium, niobium, vanadium, tantalum and iron to produce a compound of formula MH.sub.x. R.sup.1 is phenyl or phenyl substituted by at least one alkyl or alkoxy group. A mole ratio of aluminum to (R.sup.1O).sub.xM is from 0.1:1 to 1:1. The catalyst is present at a level of at least 200 ppm based on weight of aluminum.

  8. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2003-01-31

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report discusses testing that was performed for analyzing the alkali-silica reactivity of ULHS in cement slurries. DOE joined the Materials Management Service (MMS)-sponsored joint industry project ''Long-Term Integrity of Deepwater Cement under Stress/Compaction Conditions.'' Results of the project contained in two progress reports are also presented in this report.

  9. Nano-ChemoMechanical assessment of Rice Husk Ash cement by wavelength dispersive spectroscopy and nanoindentation

    E-print Network

    Abuhaikal, Muhannad (Muhannad A. R.)

    2011-01-01

    Cement global production stands at 3 Giga tons making concrete the most consumed structural mateial worldwide. This massively produced material comes with a heavy environmental footprint rendering the cement industry ...

  10. 76 FR 76760 - Gray Portland Cement and Cement Clinker From Japan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-08

    ...No. 731-TA-461 (Third Review)] Gray Portland Cement and Cement Clinker From...revocation of the antidumping duty order on gray Portland cement and cement clinker from...Publication 4281 (December 2011), entitled Gray Portland Cement and Cement Clinker...

  11. Sequential processing during noun phrase production.

    PubMed

    Bürki, Audrey; Sadat, Jasmin; Dubarry, Anne-Sophie; Alario, F-Xavier

    2016-01-01

    This study examined whether the brain operations involved during the processing of successive words in multi word noun phrase production take place sequentially or simultaneously. German speakers named pictures while ignoring a written distractor superimposed on the picture (picture-word interference paradigm) using the definite determiner and corresponding German noun. The gender congruency and the phonological congruency (i.e., overlap in first phonemes) between target and distractor were manipulated. Naming responses and EEG were recorded. The behavioural performance replicated both the phonology and the gender congruency effects (i.e., shorter naming latencies for gender congruent than incongruent and for phonologically congruent than incongruent trials). The phonological and gender manipulations also influenced the EEG data. Crucially, the two effects occurred in different time windows and over different sets of electrodes. The phonological effect was observed substantially earlier than the gender congruency effect. This finding suggests that the processing of determiners and nouns during determiner noun phrase production occurs at least partly sequentially. PMID:26407338

  12. Microbial production of scleroglucan and downstream processing

    PubMed Central

    Castillo, Natalia A.; Valdez, Alejandra L.; Fariña, Julia I.

    2015-01-01

    Synthetic petroleum-based polymers and natural plant polymers have the disadvantage of restricted sources, in addition to the non-biodegradability of the former ones. In contrast, eco-sustainable microbial polysaccharides, of low-cost and standardized production, represent an alternative to address this situation. With a strong global market, they attracted worldwide attention because of their novel and unique physico-chemical properties as well as varied industrial applications, and many of them are promptly becoming economically competitive. Scleroglucan, a ?-1,3-?-1,6-glucan secreted by Sclerotium fungi, exhibits high potential for commercialization and may show different branching frequency, side-chain length, and/or molecular weight depending on the producing strain or culture conditions. Water-solubility, viscosifying ability and wide stability over temperature, pH and salinity make scleroglucan useful for different biotechnological (enhanced oil recovery, food additives, drug delivery, cosmetic and pharmaceutical products, biocompatible materials, etc.), and biomedical (immunoceutical, antitumor, etc.) applications. It can be copiously produced at bioreactor scale under standardized conditions, where a high exopolysaccharide concentration normally governs the process optimization. Operative and nutritional conditions, as well as the incidence of scleroglucan downstream processing will be discussed in this chapter. The relevance of using standardized inocula from selected strains and experiences concerning the intricate scleroglucan scaling-up will be also herein outlined. PMID:26528259

  13. Microbial production of scleroglucan and downstream processing.

    PubMed

    Castillo, Natalia A; Valdez, Alejandra L; Fariña, Julia I

    2015-01-01

    Synthetic petroleum-based polymers and natural plant polymers have the disadvantage of restricted sources, in addition to the non-biodegradability of the former ones. In contrast, eco-sustainable microbial polysaccharides, of low-cost and standardized production, represent an alternative to address this situation. With a strong global market, they attracted worldwide attention because of their novel and unique physico-chemical properties as well as varied industrial applications, and many of them are promptly becoming economically competitive. Scleroglucan, a ?-1,3-?-1,6-glucan secreted by Sclerotium fungi, exhibits high potential for commercialization and may show different branching frequency, side-chain length, and/or molecular weight depending on the producing strain or culture conditions. Water-solubility, viscosifying ability and wide stability over temperature, pH and salinity make scleroglucan useful for different biotechnological (enhanced oil recovery, food additives, drug delivery, cosmetic and pharmaceutical products, biocompatible materials, etc.), and biomedical (immunoceutical, antitumor, etc.) applications. It can be copiously produced at bioreactor scale under standardized conditions, where a high exopolysaccharide concentration normally governs the process optimization. Operative and nutritional conditions, as well as the incidence of scleroglucan downstream processing will be discussed in this chapter. The relevance of using standardized inocula from selected strains and experiences concerning the intricate scleroglucan scaling-up will be also herein outlined. PMID:26528259

  14. Fractional exhaled nitric oxide among cement factory workers: a cross sectional study

    PubMed Central

    Tungu, Alexander Mtemi; Bråtveit, Magne; Mamuya, Simon D; Moen, Bente E

    2013-01-01

    Background It has been suggested that dust exposure causes airway inflammation among cement factory workers. However, there is limited information on the mechanisms of this effect. We explored any associations between total dust exposure and fractional exhaled nitric oxide (FENO) as a marker of airway eosinophilic inflammation among cement production workers in Tanzania. We also examined possible differences in FENO concentration between workers in different parts of the production line. Methodology We examined 127 cement workers and 28 controls from a mineral water factory. An electrochemistry-based NIOX MINO device was used to examine FENO concentration. Personal total dust was collected from the breathing zone of the study participants using 37?mm cellulose acetate filters placed in three-piece plastic cassettes. Interviews on workers’ background information were conducted in the Swahili language. Results We found equal concentrations of FENO among exposed workers and controls (geometric mean (GM)=16?ppb). The GM for total dust among the exposed workers and controls was 5.0 and 0.6?mg/m3, respectively. The FENO concentrations did not differ between the exposed workers with high (GM?5?mg/m3) and low (GM<5?mg/m3) total dust exposure. There was no significant difference in FENO concentration between workers in the two main stages of the cement production process. Conclusions We did not find any difference in FENO concentration between dust-exposed cement workers and controls, and there were similar FENO concentrations among workers in the two main stages of cement production. PMID:23243102

  15. Parallel-processing techniques for production systems

    SciTech Connect

    da Mota Tenorio, M.F.

    1987-01-01

    Production systems static and dynamic characteristics are modeled with the use of graph grammar, in order to create means to increase the processing efficiency and the use of parallel computation through compile-time analysis. The model is used to explicate rule interaction, so that proofs of equivalence between knowledge bases can be attempted. Solely relying on program static characteristics shown by the model, a series of observations are made to determine the system dynamic characteristics and modifications to the original knowledge base are suggested as a means of increasing efficiency and decreasing overall search and computational effort. Dependencies between the rules are analyzed and different approaches for automatic detection are presented. From rule dependences, tools for programming environments,logical evaluation of search spaces and Petri net models of production systems are shown. An algorithm for the allocation and partitioning of a production system into a multiprocessor system is also shown, and addresses the problems of communication and execution of these systems in parallel. Finally, the results of a simulator constructed to test several strategies, networks, and algorithms are presented.

  16. Pinellas Plant facts. [Products, processes, laboratory facilities

    SciTech Connect

    Not Available

    1986-09-01

    This plant was built in 1956 in response to a need for the manufacture of neutron generators, a principal component in nuclear weapons. The neutron generators consist of a miniaturized linear ion accelerator assembled with the pulsed electrical power supplies required for its operation. The ion accelerator, or neutron tube, requires ultra clean, high vacuum technology: hermetic seals between glass, ceramic, glass-ceramic, and metal materials: plus high voltage generation and measurement technology. The existence of these capabilities at the Pinellas Plant has led directly to the assignment of the lightning arrester connector, specialty capacitor, vacuum switch, and crystal resonator. Active and reserve batteries and the radioisotopically-powered thermoelectric generator draw on the materials measurement and controls technologies which are required to ensure neutron generator life. A product development and production capability in alumina ceramics, cermet (electrical) feedthroughs, and glass ceramics has become a specialty of the plant; the laboratories monitor the materials and processes used by the plant's commercial suppliers of ferroelectric ceramics. In addition to the manufacturing facility, a production development capability is maintained at the Pinellas Plant.

  17. Downstream Processing of Synechocystis for Biofuel Production

    NASA Astrophysics Data System (ADS)

    Sheng, Jie

    Lipids and free fatty acids (FFA) from cyanobacterium Synechocystis can be used for biofuel (e.g. biodiesel or renewable diesel) production. In order to utilize and scale up this technique, downstream processes including culturing and harvest, cell disruption, and extraction were studied. Several solvents/solvent systems were screened for lipid extraction from Synechocystis. Chloroform + methanol-based Folch and Bligh & Dyer methods were proved to be "gold standard" for small-scale analysis due to their highest lipid recoveries that were confirmed by their penetration of the cell membranes, higher polarity, and stronger interaction with hydrogen bonds. Less toxic solvents, such as methanol and MTBE, or direct transesterification of biomass (without preextraction step) gave only slightly lower lipid-extraction yields and can be considered for large-scale application. Sustained exposure to high and low temperature extremes severely lowered the biomass and lipid productivity. Temperature stress also triggered changes of lipid quality such as the degree of unsaturation; thus, it affected the productivities and quality of Synechocystis-derived biofuel. Pulsed electric field (PEF) was evaluated for cell disruption prior to lipid extraction. A treatment intensity > 35 kWh/m3 caused significant damage to the plasma membrane, cell wall, and thylakoid membrane, and it even led to complete disruption of some cells into fragments. Treatment by PEF enhanced the potential for the low-toxicity solvent isopropanol to access lipid molecules during subsequent solvent extraction, leading to lower usage of isopropanol for the same extraction efficiency. Other cell-disruption methods also were tested. Distinct disruption effects to the cell envelope, plasma membrane, and thylakoid membranes were observed that were related to extraction efficiency. Microwave and ultrasound had significant enhancement of lipid extraction. Autoclaving, ultrasound, and French press caused significant release of lipid into the medium, which may increase solvent usage and make medium recycling difficult. Production of excreted FFA by mutant Synechocystis has the potential of reducing the complexity of downstream processing. Major problems, such as FFA precipitation and biodegradation by scavengers, account for FFA loss in operation. Even a low concentration of FFA scavengers could consume FFA at a high rate that outpaced FFA production rate. Potential strategies to overcome FFA loss include high pH, adsorptive resin, and sterilization techniques.

  18. Excessive exposure to dust among cleaners in the Ethiopian cement industry.

    PubMed

    Zeleke, Zeyede K; Moen, Bente E; Bråtveit, Magne

    2011-09-01

    Personal exposure to dust in cement factories occurs at all stages of the production process and is likely to vary between different stages of the process. Previous studies on cement production have focused on dust exposure among process operators and machine attendants. This study characterizes personal exposure to total and respirable dust among production workers in two cement factories in Ethiopia, with particular focus on cleaners. In Ethiopian cement plants, flow lines are partly open, and cleaning workers use brooms and shovels to remove dust that has settled on floors and machines. Personal full-shift samples of total (n = 150) and respirable dust (n = 36) were taken in the breathing zones of 105 cement workers. Samples of total and respirable dust were collected on 37-mm cellulose acetate filters of closed-face cassettes and in plastic respirable cyclones, respectively. In both factories, cleaners had significantly higher exposures to total and respirable dust than other production workers. Among cleaners, the geometric means for total and respirable dust exposure were 549 and 6.8 mg/m(3) in Factory A, and 153 and 2.8 mg/m(3) in Factory B. Temporal variability (within-worker) dominated the variability in the cleaners' total dust exposures. The distance from machines while performing cleaning tasks and the fraction of working hours spent on cleaning explained about 73% of the temporal variability in total dust exposure among cleaners. Only 7% of the production workers used respiratory protective devices. Preventive measures are needed to reduce dust exposure. PMID:21830870

  19. Low fluid leakoff cementing compositions and filtration control additive for cement

    SciTech Connect

    Forrest, G.T.

    1993-07-20

    A cementing composition is described, for cementing oil or gas wells penetrating subterranean formations, capable of forming a fluid slurry when mixed with water comprising: dry hydraulic cement; and a filtration control additive of from about 0.2 to 5.0 percent by weight, based upon dry hydraulic cement, of finely ground peanut hulls, wherein 10 percent or more of the finely ground peanut hulls is in the particle size range of less than 20 standard sieve mesh and greater than 500 standard sieve mesh. In a process for cementing a casing in an oil or gas well penetrating a subterranean formation wherein a cement slurry, formed by mixing water and hydraulic cement, is pumped down the well to flow upwardly between the casing and the subterranean formation, the improvement is described comprising: utilizing as a filtration control additive of from about 0.2 to 5.0 percent by weight, based upon dry hydraulic cement, of finely ground peanut hulls, and utilizing finely ground peanut hulls wherein 10 percent or more of the finely ground peanut hulls is in the particle size range of less than 20 standard sieve mesh and greater than 500 standard sieve mesh.

  20. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Approval of labeling for egg products processed in exempted egg products processing plants. 590.680 Section 590.680 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION...

  1. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Approval of labeling for egg products processed in exempted egg products processing plants. 590.680 Section 590.680 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION...

  2. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Approval of labeling for egg products processed in exempted egg products processing plants. 590.680 Section 590.680 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION...

  3. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Approval of labeling for egg products processed in exempted egg products processing plants. 590.680 Section 590.680 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION...

  4. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Approval of labeling for egg products processed in exempted egg products processing plants. 590.680 Section 590.680 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION...

  5. Lunar cement and lunar concrete

    NASA Technical Reports Server (NTRS)

    Lin, T. D.

    1991-01-01

    Results of a study to investigate methods of producing cements from lunar materials are presented. A chemical process and a differential volatilization process to enrich lime content in selected lunar materials were identified. One new cement made from lime and anorthite developed compressive strengths of 39 Mpa (5500 psi) for 1 inch paste cubes. The second, a hypothetical composition based on differential volatilization of basalt, formed a mineral glass which was activated with an alkaline additive. The 1 inch paste cubes, cured at 100C and 100 percent humidity, developed compressive strengths in excess of 49 Mpa (7100 psi). Also discussed are tests made with Apollo 16 lunar soil and an ongoing investigation of a proposed dry mix/steam injection procedure for casting concrete on the Moon.

  6. Cascaded processing in written compound word production

    PubMed Central

    Bertram, Raymond; Tønnessen, Finn Egil; Strömqvist, Sven; Hyönä, Jukka; Niemi, Pekka

    2015-01-01

    In this study we investigated the intricate interplay between central linguistic processing and peripheral motor processes during typewriting. Participants had to typewrite two-constituent (noun-noun) Finnish compounds in response to picture presentation while their typing behavior was registered. As dependent measures we used writing onset time to assess what processes were completed before writing and inter-key intervals to assess what processes were going on during writing. It was found that writing onset time was determined by whole word frequency rather than constituent frequencies, indicating that compound words are retrieved as whole orthographic units before writing is initiated. In addition, we found that the length of the first syllable also affects writing onset time, indicating that the first syllable is fully prepared before writing commences. The inter-key interval results showed that linguistic planning is not fully ready before writing, but cascades into the motor execution phase. More specifically, inter-key intervals were largest at syllable and morpheme boundaries, supporting the view that additional linguistic planning takes place at these boundaries. Bigram and trigram frequency also affected inter-key intervals with shorter intervals corresponding to higher frequencies. This can be explained by stronger memory traces for frequently co-occurring letter sequences in the motor memory for typewriting. These frequency effects were even larger in the second than in the first constituent, indicating that low-level motor memory starts to become more important during the course of writing compound words. We discuss our results in the light of current models of morphological processing and written word production. PMID:25954182

  7. 9 CFR 590.680 - Approval of labeling for egg products processed in exempted egg products processing plants.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...processed in exempted egg products processing plants. 590.680 Section 590.680 Animals...INSPECTION ACT) Exempted Egg Products Plants § 590.680 Approval of labeling...processed in exempted egg products processing plants. (a) The labels for egg...

  8. Hydration kinetics of cement composites with varying water-cement ratio using terahertz spectroscopy

    NASA Astrophysics Data System (ADS)

    Ray, Shaumik; Dash, Jyotirmayee; Devi, Nirmala; Sasmal, Saptarshi; Pesala, Bala

    2015-03-01

    Cement is mixed with water in an optimum ratio to form concrete with desirable mechanical strength and durability. The ability to track the consumption of major cement constituents, viz., Tri- and Dicalcium Silicates (C3S, C2S) reacting with water along with the formation of key hydration products, viz., Calcium-Silicate-Hydrate (C-S-H) which gives the overall strength to the concrete and Calcium Hydroxide (Ca(OH)2), a hydration product which reduces the strength and durability, using an efficient technique is highly desirable. Optimizing the amount of water to be mixed with cement is one of the main parameters which determine the strength of concrete. In this work, THz spectroscopy has been employed to track the variation in hydration kinetics for concrete samples with different water-cement ratios, viz., 0.3, 0.4, 0.5 and 0.6. Results show that for the sample with water-cement ratio of 0.3, significant amount of the C3S and C2S remain unreacted even after the initial hydration period of 28 days while for the cement with water-cement ratio of 0.6, most of the constituents get consumed during this stage. Analysis of the formation of Ca(OH)2 has been done which shows that the concrete sample with water-cement ratio of 0.6 produces the highest amount of Ca(OH)2 due to higher consumption of C3S/C2S in presence of excess water which is not desirable. Samples with water-cement ratio of 0.4 and 0.5 show more controlled reaction during the hydration which can imply formation of an optimized level of desired hydration products resulting in a more mechanically strong and durable concrete.

  9. Emissions testing of a wet-cement kiln at Hannibal, Missouri. Draft report

    SciTech Connect

    Garg, S.; Klamm, S.; March, D.; Onstot, J.; Romeu, A.

    1990-12-01

    The EPA is developing regulations to control emissions of products of incomplete combustion (PICs) from cement kilns. The emission parameters planned for use in this regulation are total hydrocarbons and carbon monoxide. To investigate the use of these parameters as surrogates for PICs, more information from full-scale testing of wet cement kilns is needed. Data are also needed for development of regulations to control emissions of hydrogen chloride. As part of this data-gathering effort, a test was conducted at the Continental Cement Company in Hannibal, MO. One reason that Continental was selected by EPA for the test is that the facility uses a wet process kiln and also burns both liquid and solid (powdered) hazardous waste as supplementary fuels in the kiln. All test activities were conducted for and under the direction of EPA/OSW, Waste Treatment Branch.

  10. Reaction of CO2 and brine at the interface between Portland cement and casing steel: Application to CO2 sequestration

    NASA Astrophysics Data System (ADS)

    Carey, J. W.; Zhang, J.; Lichtner, P. C.; Grigg, R.; Svec, B.; Pawar, R.

    2008-12-01

    Prediction of CO2 leakage through wellbore systems is a multiscale problem in geologic sequestration. In order for wellbore leakage to occur, km-scale processes must deliver CO2 from the point of injection to the wellbore. But, in order for the wellbore to actually leak, ?m-scale processes must operate to allow CO2 to flow up the wellbore. In this study, we describe experiments and modeling of microscale processes accompanying CO2 leakage along the cement-casing interface. This work fits within a broader predictive study of CO2 sequestration performance (Viswanathan et al. 2008, Env Sci and Tech, in press) that includes calculation of CO2-migration times to wellbores. Experiments carried out in this report consisted of synthetic wellbore systems constructed of Portland cement and casing-grade steel in which a mixture of CO2 and brine were forced along the cement-casing interface at in situ sequestration conditions (40 °C and 14 MPa). The CO2-brine mixture was pre- equilibrated by flow through limestone before encountering the cement-casing composite. (The limestone- equilibrated fluid was calculated to be strongly out of equilibrium with both cement and the casing.) We used a high CO2-brine flux (10-20 ml/hour along the interface) and hypothesized that the interface would widen with time due to dissolution of either or both cement and steel. In addition to experiments, we conducted reactive transport modeling of cement reactivity using FLOTRAN, which was modified to allow representation of solid solution in the dominant cement phase, calcium-silicate-hydrate. We also developed a corrosion model for the steel. The experimental results showed that the steel was more reactive than the Portland cement. Extensive deposits or oxidation products of FeCO3-rich material developed at the interface and in some places led to an apparent closure of the interface despite the large flux through the system. In contrast, alteration of the cement appeared to be limited by diffusion of CO2 into the cement matrix and carbonation of the cement to CaCO3. The cement interface did not appear to have been significantly eroded. The experiment was used to calibrate numerical models for corrosion rates and for cement carbonation. These results were applied to interpret samples recovered from a CO2-enhanced oil recovery field (SACROC in West Texas; Carey et al. 2007, Int J. Greenhouse Gas Control, 1: 75-85). The results suggest that CO2-brine flux must have been limited along the cement-casing interface because the casing showed very little corrosion. They also suggest that CO2 penetration along the cement-formation interface was limited in volume because the depth of carbonation at SACROC was limited. These microscale models suggest that cement-casing flow has the potential to be self-limiting due to precipitation of CO2 and that standard logging measurements of casing integrity can be used to assess whether significant flow of CO2-brine has occurred at the casing interface.

  11. Wellbore cement fracture evolution at the cement–basalt caprock interface during geologic carbon sequestration

    SciTech Connect

    Jung, Hun Bok; Kabilan, Senthil; Carson, James P.; Kuprat, Andrew P.; Um, Wooyong; Martin, Paul F.; Dahl, Michael E.; Kafentzis, Tyler A.; Varga, Tamas; Stephens, Sean A.; Arey, Bruce W.; Carroll, KC; Bonneville, Alain; Fernandez, Carlos A.

    2014-08-01

    Composite Portland cement-basalt caprock cores with fractures, as well as neat Portland cement columns, were prepared to understand the geochemical and geomechanical effects on the integrity of wellbores with defects during geologic carbon sequestration. The samples were reacted with CO2-saturated groundwater at 50 ºC and 10 MPa for 3 months under static conditions, while one cement-basalt core was subjected to mechanical stress at 2.7 MPa before the CO2 reaction. Micro-XRD and SEM-EDS data collected along the cement-basalt interface after 3-month reaction with CO2-saturated groundwater indicate that carbonation of cement matrix was extensive with the precipitation of calcite, aragonite, and vaterite, whereas the alteration of basalt caprock was minor. X-ray microtomography (XMT) provided three-dimensional (3-D) visualization of the opening and interconnection of cement fractures due to mechanical stress. Computational fluid dynamics (CFD) modeling further revealed that this stress led to the increase in fluid flow and hence permeability. After the CO2-reaction, XMT images displayed that calcium carbonate precipitation occurred extensively within the fractures in the cement matrix, but only partially along the fracture located at the cement-basalt interface. The 3-D visualization and CFD modeling also showed that the precipitation of calcium carbonate within the cement fractures after the CO2-reaction resulted in the disconnection of cement fractures and permeability decrease. The permeability calculated based on CFD modeling was in agreement with the experimentally determined permeability. This study demonstrates that XMT imaging coupled with CFD modeling represent a powerful tool to visualize and quantify fracture evolution and permeability change in geologic materials and to predict their behavior during geologic carbon sequestration or hydraulic fracturing for shale gas production and enhanced geothermal systems.

  12. Product development processes and their importance to organizational capabilities

    E-print Network

    Liu, Bing, 1968 Oct. 25-

    2003-01-01

    Product development is a creative and interdisciplinary activity that transforms a market opportunity and technological innovation into successful products. It is a set of activity-based processes in a product-oriented ...

  13. Product-level bill of material development process : managing complexity

    E-print Network

    Lester, Ryan John

    2009-01-01

    Cisco's current process for developing and maintaining product-level bills of materials (BOMs) has resulted in inconsistencies in BOM structure leading to product launch delays, increased product support costs, and lower ...

  14. Alignment strategies for drug product process development and manufacturing

    E-print Network

    Garvin, Christopher John

    2012-01-01

    The transfer of information between the drug product development and manufacturing organizations is fundamental to drug product commercialization. This information is used to characterize the product-process interaction ...

  15. Paleoenvironmental Controls on Early Cementation of Organic-Rich Shales in the Eagle Ford Group

    NASA Astrophysics Data System (ADS)

    Kruse, K.; Tice, M. M.

    2013-12-01

    Early carbonate cements have the potential to alter fracture toughness, and carbonate can be either promoted or inhibited by microbial processes in different redox zones. It is therefore possible that basin redox evolution could indirectly control early diagenesis and modify reservoir properties of corresponding shale units. The goals of this study are to analyze geochemical characteristics of the Late Cretaceous Eagle Ford Group in McMullen County, Texas in order to test the hypotheses that (1) the redox state of the water column controlled carbonate cement abundance and (2) carbonate cement lowered organic matter content by volumetric dilution. An X-ray analytical microscope was used to map elemental compositions of fresh core samples spanning the Eagle Ford Group. Resultant maps were used to characterize carbonate cements and to estimate the redox state of the overlying water column during deposition as proxied by the relative abundances of the trace metals Mo, V, Cr, and Zn. Preliminary results indicate that cementation occurred early relative to compaction. Ti-K?1-normalized Mo K?1 and Ca K?1 fluorescence intensities are positively correlated throughout the unit, suggesting that carbonate cementation was promoted by basin euxinia. Total organic carbon is negatively correlated with (Ca K?1)/(Ti K?1) fluorescence ratio in the upper Eagle Ford Group, consistent with volumetric dilution of sedimentary organic matter by diagenetic cementation prior to compaction. In contrast, there is no significant correlation between total organic carbon and carbonate content in the more organic-rich lower Eagle Ford Group, suggesting that variations in organic matter production, preservation, or dilution by siliciclastic input were also important in controlling final organic content.

  16. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2004-01-30

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report discusses testing that was performed for analyzing the alkali-silica reactivity of ULHS in cement slurries.

  17. Atmospheric Processing Module for Mars Propellant Production

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony; Gibson, Tracy; Captain, James; Athman, Robert; Nugent, Matthew; Parks, Steven; Devor, Robert

    2013-01-01

    The multi-NASA center Mars Atmosphere and Regolith COllector/PrOcessor for Lander Operations (MARCO POLO) project was established to build and demonstrate a methane/oxygen propellant production system in a Mars analog environment. Work at the Kennedy Space Center (KSC) Applied Chemistry Laboratory is focused on the Atmospheric Processing Module (APM). The purpose of the APM is to freeze carbon dioxide from a simulated Martian atmosphere containing the minor components nitrogen, argon, carbon monoxide, and water vapor at Martian pressures (approx.8 torr) by using dual cryocoolers with alternating cycles of freezing and sublimation. The resulting pressurized CO2 is fed to a methanation subsystem where it is catalytically combined with hydrogen in a Sabatier reactor supplied by the Johnson Space Center (JSC) to make methane and water vapor. We first used a simplified once-through setup and later employed a HiCO2 recycling system to improve process efficiency. This presentation and paper will cover (1) the design and selection of major hardware items, such as the cryocoolers, pumps, tanks, chillers, and membrane separators, (2) the determination of the optimal cold head design and flow rates needed to meet the collection requirement of 88 g CO2/hr for 14 hr, (3) the testing of the CO2 freezer subsystem, and (4) the integration and testing of the two subsystems to verify the desired production rate of 31.7 g CH4/hr and 71.3 g H2O/hr along with verification of their purity. The resulting 2.22 kg of CH4/O2 propellant per 14 hr day (including O2 from electrolysis of water recovered from regolith, which also supplies the H2 for methanation) is of the scale needed for a Mars Sample Return mission. In addition, the significance of the project to NASA's new Mars exploration plans will be discussed.

  18. Atmospheric Processing Module for Mars Propellant Production

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony; Gibson, Tracy; Captain, James; Athman, Robert; Nugent, Matthew; Parks, Steven; Devor, Robert

    2013-01-01

    The multi-NASA center Mars Atmosphere and Regolith COllector/PrOcessor for Lander Operations (MARCO POLO) project was established to build and demonstrate a methane/oxygen propellant production system in a Mars analog environment. Work at the Kennedy Space Center (KSC) Applied Chemistry Laboratory is focused on the Atmospheric Processing Module (APM). The purpose of the APM is to freeze carbon dioxide from a simulated Martian atmosphere containing the minor components nitrogen, argon, carbon monoxide, and water vapor at Martian pressures (8 torr) by using dual cryocoolers with alternating cycles of freezing and sublimation. The resulting pressurized CO2 is fed to a methanation subsystem where it is catalytically combined with hydrogen in a Sabatier reactor supplied by the Johnson Space Center (JSC) to make methane and water vapor. We first used a simplified once-through setup and later employed a HiCO2 recycling system to improve process efficiency. This presentation and paper will cover (1) the design and selection of major hardware items, such as the cryocoolers, pumps, tanks, chillers, and membrane separators, (2) the determination of the optimal cold head design and flow rates needed to meet the collection requirement of 88 g CO2/hr for 14 hr, (3) the testing of the CO2 freezer subsystem, and (4) the integration and testing of the two subsystems to verify the desired production rate of 31.7 g CH4/hr and 71.3 g H20/hr along with verification of their purity. The resulting 2.22 kg of CH4/O2 propellant per 14 hr day (including O2 from electrolysis of water recovered from regolith, which also supplies the H2 for methanation) is of the scale needed for a Mars Sample Return mission. In addition, the significance of the project to NASA's new Mars exploration plans will be discussed.

  19. High-productivity automatic GTAW process

    SciTech Connect

    Imaizumi, H.; Kato, T.; Murakami, Y.

    1994-12-31

    Gas tungsten arc welding (GTAW) has, since developed by AIRCO, spread globally as a weld process which assures a quality weld. However, the only drawback with GTAW is low productivity and we have challenged the subject in how we could improve that. To that end, we set the target of 3 times deposition rate as compared to conventional TIG. With conventional TIG arc, arc spread angle ranges 130{degrees} to 140{degrees}; to improve energy density, we have employed double flux TIG of SAF, France to converge the arc down to 80{degrees}. Consequently, energy density was upped to 4 times of conventional TIG, thus penetration depth and filler wire feed rated increased up to 2 to 4 times. We have succeeded in controlling cool-down in the molten pool, enabling the utilization of highly-converged TIG arc and preventing deposited metals burn-through for cleaner weld process, high-productivity GTAW. We find that: (1) The TIG arc spread angle is convergeable from 140{degrees} down to 80{degrees}; heat energy to be 3.5 times of that obtainable conventionally. (2) 65{emdash}80 g/min attained with 500A and C.S. in flat position, and 35{emdash}40 g/min., with all-position pipe weld. (3) 2{emdash}3 times efficiency improvement, obtained with work in C.S., S.S., and Inconel. (4) Excellent impact value obtainable despite heat-input increase. (5) Fume-less, spatterless, gouging-less and grindingless weld is obtainable; we were successful in improving the operational environment.

  20. Matrix control cementing slurry

    SciTech Connect

    Arpenter, R.B.

    1986-02-11

    This patent describes a method of cementing a well bore. The method consists of 1.) mixing together at ambient temperatures at the well surface a hydraulic cement, water, in an effective amount to produce a pumpable slurry, and a polyvinyl acetate-polyvinyl alcohol polymer, which is insoluble in the slurry at ambient temperatures. The polymer has a greater than about 95 percent acetate groups converted to hydroxyl groups. The polymer is heated to actuable solubilization in the cement slurry at temperatures above about 120/sup 0/F. The solubilizing of the polyvinyl acetate-polyvinyl alcohol polymer in the slurry prior to the setting of the slurry by pumping the cement slurry to a desired location in the well bore. This action increases the temperature of the slurry; and 2.) allows the cement slurry to harden to a solid mass.

  1. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2002-01-23

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report includes results from laboratory testing of ULHS systems along with other lightweight cement systems: foamed and sodium silicate slurries. Comparison studies of the three cement systems examined several properties: tensile strength, Young's modulus, water permeability, and shear bond. Testing was also done to determine the effect that temperature cycling has on the shear bond properties of the cement systems. In addition, analysis was carried out to examine alkali silica reactivity of slurries containing ULHS. Data is also presented from a study investigating the effects of mixing and pump circulation on breakage of ULHS. Information is also presented about the field application of ULHS in cementing a 7-in. intermediate casing in south Texas.

  2. Technology Transfer and the Product Development Process

    SciTech Connect

    Mock, John E.

    1989-03-21

    It is my pleasure this morning to address a topic that is much talked about in passing but rarely examined from a first person point of view. That topic is Technology Transfer. Over the next 30 minutes I'd like to approach Technology Transfer within the context of the Product Development Process looking at it from the perspectives of the federal government researcher and the industry manufacturer/user. Fist let us recognize that we are living in an ''Information Age'', where global economic and military competition is determined as much by technology as it is by natural resource assets. It is estimated that technical/scientific information is presently growing at a rate of l3 percent per year; this is expected to increase to 30 percent per year by the turn of the century. In fact, something like 90 percent of all scientific knowledge has been generated in the last 30 years; this pool will double again in the next 10-15 years (Exhibit 1). Of all the scientists and engineers throughout history, 90% live and work in the present time. Successfully managing this technical information/knowledge--i.e., transforming the results of R&D to practical applications--will be an important measure of national strength. A little over a dozen years ago, the United States with only 5 percent of the world's population was generating approximately 75 percent of the world's technology. The US. share is now 50 percent and may decline to 30 percent by the turn of the century. This decline won't be because of downturn in U.S. technological advances but because the other 95 percent of the world's population will be increasing its contribution. Economic and military strength then, will be determined by how quickly and successfully companies, industries, and nations can apply new technological information to practical applications--i.e., how they manage technology transfer within the context of the product development process. Much discussion and pronouncements are ongoing in public forums today over the apparent decline in global competitiveness of U.S. industry. The question is why does U.S. industry not succeed in the development and marketing of competitive products when they lead in the generation of new technology.

  3. Natural products and the aging process.

    PubMed

    Ergin, Volkan; Bali, Elif Burcu; Hariry, Reza Ebrahimi; Karasu, Cimen

    2013-12-01

    Abstract Literature surveys show that the most of the research that have been conducted on the effect of herbal remedies on many tissue pathologies, including metabolic disturbances, cardiovascular decline, neurodegeneration, cataract, diabetic retinopathy and skin inflammation, all lead to an accelerated aging process. The increased carbonylation of proteins (carbonyl stress) disturbing their function has been indicated as an underlying mechanism of cellular senescence and age-related diseases. Because it is also linked to the carbonyl stress, aging chronic disease and inflammation plays an important role in understanding the clinical implications of cellular stress response and relevant markers. Greater knowledge of the molecular and cellular mechanisms involved in several pathologies associated with aging would provide a better understanding to help us to develop suitable strategies, use specific targets to mitigate the effect of human aging, prevent particularly chronic degenerative diseases and improve quality of life. However, research is lacking on the herbal compounds affecting cellular aging signaling as well as studies regarding the action mechanism(s) of natural products in prevention of the age-related disease. This review provides leads for identifying new medicinal agents or potential phytochemical drugs from plant sources for the prevention or delaying cellular aging processes and the treatment of some disorders related with accelerated body aging. PMID:25436747

  4. Process for production of a borohydride compound

    DOEpatents

    Allen, Nathan Tait; Butterick, III, Robert; Chin, Arthur Achhing; Millar, Dean Michael; Molzahn, David Craig

    2014-08-19

    A process for production of a borohydride compound M(BH.sub.4).sub.y. The process has three steps. The first step combines a compound of formula (R.sup.1O).sub.yM with aluminum, hydrogen and a metallic catalyst containing at least one metal selected from the group consisting of titanium, zirconium, hafnium, niobium, vanadium, tantalum and iron to produce a compound of formula M(AlH.sub.3OR.sup.1).sub.y, wherein R.sup.1 is phenyl or phenyl substituted by at least one alkyl or alkoxy group; M is an alkali metal, Be or Mg; and y is one or two; wherein the catalyst is present at a level of at least 200 ppm based on weight of aluminum. The second step combines the compound of formula M(AlH.sub.3OR.sup.1).sub.y with a borate, boroxine or borazine compound to produce M(BH.sub.4).sub.y and a byproduct mixture containing alkali metal and aluminum aryloxides. The third step separates M(BH.sub.4).sub.y from the byproduct mixture.

  5. Integrated Product and Process Data for B2B Collaboration

    SciTech Connect

    Kulvatunyou, Boonserm; Ivezic, Nenad; Jones, Albert; Wysk, Richard A.

    2003-09-01

    Collaborative development of engineered products in a business-to-business (B2B) environment will require more than just the selection of components from an on-line catalogue. It will involve the electronic exchange of product, process, and production engineering information during both design and manufacturing. While the state-of-the-practice does include a variety of ways to exchange product data electronically, it does not extend to the exchange of manufacturing process data. The reason is simple; process data is usually tied to specific manufacturing resources. These resources are not known typically at product development time. This paper proposes an approach, called an Integrated Product and Process Data (IPPD), where manufacturing process data is considered during product development. This approach replaces traditional process plans, which are resource specific, with a resource-independent process representation. Such a representation will allow a much wider collaboration among business partners and provide the necessary base for collaborative product development.

  6. Cogrinding significance for calcium carbonate-calcium phosphate mixed cement. II. Effect on cement properties.

    PubMed

    Tadier, Solène; Bolay, Nadine Le; Fullana, Sophie Girod; Cazalbou, Sophie; Charvillat, Cédric; Labarrère, Michel; Boitel, Daniel; Rey, Christian; Combes, Christèle

    2011-11-01

    In the present study, we aim to evaluate the contribution of the cogrinding process in controlling calcium carbonate-dicalcium phosphate dihydrate cement properties. We set a method designed to evaluate phase separation, usually occurring during paste extrusion, which is quantitative, reliable, and discriminating and points out the determining role of cogrinding to limit filter-pressing. We show that solid-phase cogrinding leads to synergistic positive effects on cement injectability, mechanical properties, and radio-opacity. It allows maintaining a low (<0.4 kg) and constant load during the extrusion of paste, and the paste's composition remains constant and close to that of the initial paste. Analogous behavior was observed when adding a third component into the solid phase, especially SrCO(3) as a contrasting agent. Moreover, the cement's mechanical properties can be enhanced by lowering the L/S ratio because of the lower plastic limit. Finally, unloaded or Sr-loaded cements show uniform and increased optical density because of the enhanced homogeneity of dry component distribution. Interestingly, this study reveals that cogrinding improves and controls essential cement properties and involves processing parameters that could be easily scaled up. This constitutes a decisive advantage for the development of calcium carbonate-calcium phosphate mixed cements and, more generally, of injectable multicomponent bone cements that meet a surgeon's requirements. PMID:21953727

  7. A literature review of mixed waste components: Sensitivities and effects upon solidification/stabilization in cement-based matrices

    SciTech Connect

    Mattus, C.H.; Gilliam, T.M.

    1994-03-01

    The US DOE Oak Ridge Field Office has signed a Federal Facility Compliance Agreement (FFCA) regarding Oak Ridge Reservation (ORR) mixed wastes subject to the land disposal restriction (LDR) provisions of the Resource conservation and Recovery Act. The LDR FFCA establishes an aggressive schedule for conducting treatability studies and developing treatment methods for those ORR mixed (radioactive and hazardous) wastes listed in Appendix B to the Agreement. A development, demonstration, testing, and evaluation program has been initiated to provide those efforts necessary to identify treatment methods for all of the wastes that meet Appendix B criteria. The program has assembled project teams to address treatment development needs in a variety of areas, including that of final waste forms (i.e., stabilization/solidification processes). A literature research has been performed, with the objective of determining waste characterization needs to support cement-based waste-form development. The goal was to determine which waste species are problematic in terms of consistent production of an acceptable cement-based waste form and at what concentrations these species become intolerable. The report discusses the following: hydration mechanisms of Portland cement; mechanisms of retardation and acceleration of cement set-factors affecting the durability of waste forms; regulatory limits as they apply to mixed wastes; review of inorganic species that interfere with the development of cement-based waste forms; review of radioactive species that can be immobilized in cement-based waste forms; and review of organic species that may interfere with various waste-form properties.

  8. The density of cement phases

    SciTech Connect

    Balonis, M. Glasser, F.P.

    2009-09-15

    The densities of principal crystalline phases occurring in Portland cement are critically assessed and tabulated, in some cases with addition of new data. A reliable and self-consistent density set for crystalline phases was obtained by calculating densities from crystallographic data and unit cell contents. Independent laboratory work was undertaken to synthesize major AFm and AFt cement phases, determine their unit cell parameters and compare the results with those recorded in the literature. Parameters were refined from powder diffraction patterns using CELREF 2 software. A density value is presented for each phase, showing literature sources, in some cases describing limitations on the data, and the weighting attached to numerical values where an averaging process was used for accepted data. A brief discussion is made of the consequences of the packing of water to density changes in AFm and AFt structures.

  9. Performance Cements Focus on Sustainability

    E-print Network

    allowed in the US ASTM C 150 in 2004 AASHTO M 85 in 2007 Negligible effects Some slight performance) Inc. Concrete data ­ ASTM vs. CSA cements, 3 days #12;7 High Limestone Cements 5/21/08 Cost Holcim (US) Inc. Concrete data ­ ASTM vs. CSA cements, 7 days #12;8 High Limestone Cements 5/21/08 Cost Holcim (US

  10. Process for Converting Waste Glass Fiber into Value Added Products, Final Report

    SciTech Connect

    Hemmings, Raymond T.

    2005-12-31

    Nature of the Event: Technology demonstration. The project successfully met all of its technical objectives. Albacem has signed an exclusive licensing agreement with Vitro Minerals Inc., a specialty minerals company, to commercialize the Albacem technology (website: www.vitrominerals.com). Location: The basic research for the project was conducted in Peoria, Illinois, and Atlanta, Georgia, with third-party laboratory verification carried out in Ontario, Canada. Pilot-scale trials (multi-ton) were conducted at a facility in South Carolina. Full-scale manufacturing facilities have been designed and are scheduled for construction by Vitro Minerals during 2006 at a location in the Georgia, North Carolina, and South Carolina tri-state area. The Technology: This technology consists of a process to eliminate solid wastes generated at glass fiber manufacturing facilities by converting them to value-added materials (VCAS Pozzolans) suitable for use in cement and concrete applications. This technology will help divert up to 250,000 tpy of discarded glass fiber manufacturing wastes into beneficial use applications in the concrete construction industry. This technology can also be used for processing glass fiber waste materials reclaimed from monofills at manufacturing facilities. The addition of take-back materials and reclamation from landfills can help supply over 500,000 tpy of glass fiber waste for processing into value added products. In the Albacem process, waste glass fiber is ground to a fine powder that effectively functions as a reactive pozzolanic admixture for use in portland ce¬ment-based building materials and products, such as concrete, mortars, terrazzo, tile, and grouts. Because the waste fiber from the glass manufacturing industry is vitreous, clean, and low in iron and alkalis, the resulting pozzolan is white in color and highly consistent in chemical composition. This white pozzolan, termed VCAS Pozzolan (for Vitreous Calcium-Alumino-Silicate). is especially suited for white concrete applications where it imparts desirable benefits such as increased long-term strength and improved long-term durability of concrete products. Two U.S. patents entitled have been issued to Albacem covering the technology. Third-party validation testing has confirmed that the pozzolanic product is an excellent, high performance material that conforms to a ASTM standards and improves the strength and durability of concrete. Currently, there are no known significant competing technologies to process glass fiber manufacturing by-products and con¬vert them into value-added products. Most glass fiber-forming and fabrication wastes continue to be disposed in landfills at significant costs and with associated negative environmental impact. It is estimated that in a typical glass fiber manufactur¬ing facility, 10-20% by weight of the processed glass material is sent for dis¬posal to a landfill. Today, supplementary ce¬menting materials or mineral admixtures are key to achieving strong and durable concrete. Recovered materials such as coal fly ash, ground granulated blast furnace slag and silica fume are widely accepted and used in concrete all over the world, espe¬cially in the construction of “high performance” structures such as massive dams, bridges, subway tunnels, etc. These min¬eral admixtures are not suitable for white concrete and light-colored architectural concrete applications. Converting waste glass fibers into a high performance white pozzolan would allow white concrete producers to gain from the same durability benefits currently realized by gray concrete producers. Description of the Benefit: Albacem’s technology will enable the glass fiber industry to eliminate nearly 100% of its glass fiber produc¬tion waste streams by converting them into viable value-added products. With this technology, the glass industry can prevent the landfilling of about 250,000 tons of waste glass fiber annually. Glass manufacturers will realize improved production efficiency by reducing process costs through the elimination of solid was

  11. Conversion of historic waste treatment process for production of an LDR and WIPP/WAC compliant TRU wasteform

    SciTech Connect

    Dunn, R.P.; Wagner, R.A.

    1997-03-01

    In support of the historic weapons production mission at the, Rocky Flats Environmental Technology Site (RFETS), several liquid waste treatment processes were designed, built and operated for treatment of plutonium-contaminated aqueous waste. Most of these @ processes ultimately resulted in the production of a cemented wasteform. One of these treatment processes was the Miscellaneous Aqueous Waste Handling and Solidification Process, commonly referred to as the Bottlebox process. Due to a lack of processing demand, Bottlebox operations were curtailed in late 1989. Starting in 1992, a treatment capability for stabilization of miscellaneous, Resource Conservation and Recovery Act (RCRA) hazardous, plutonium-nitrate solutions was identified. This treatment was required to address potentially unsafe storage conditions for these liquids. The treatment would produce a TRU wasteform. It thus became necessary to restart the Bottlebox process, but under vastly different conditions and constraints than existed prior to its curtailment. This paper provides a description of the historical Bottlebox process and process controls; and then describes, in detail, all of the process and process control changes that were implemented to convert the treatment system such that a Waste Isolation Pilot Plant (WIPP) and a Land Disposal Requirements (LDR) compliant wasteform would be produced. The rationale for imposition of LDRs on a TRU wasteform is discussed. In addition, this paper discusses the program changes implemented to meet modem criticality safety, Conduct of Operations, and Department of Energy Nuclear Facility restart requirements.

  12. Atmospheric Processing Module for Mars Propellant Production

    NASA Technical Reports Server (NTRS)

    Muscatello, A.; Devor, R.; Captain, J.

    2014-01-01

    The multi-NASA center Mars Atmosphere and Regolith COllector/PrOcessor for Lander Operations (MARCO POLO) project was established to build and demonstrate a methaneoxygen propellant production system in a Mars analog environment. Work at the Kennedy Space Center (KSC) Applied Chemistry Laboratory is focused on the Atmospheric Processing Module (APM). The purpose of the APM is to freeze carbon dioxide from a simulated Martian atmosphere containing the minor components nitrogen, argon, carbon monoxide, and water vapor at Martian pressures (approx. 8 torr) by using dual cryocoolers with alternating cycles of freezing and sublimation. The resulting pressurized CO(sub 2) is fed to a methanation subsystem where it is catalytically combined with hydrogen in a Sabatier reactor supplied by the Johnson Space Center (JSC) to make methane and water vapor. We first used a simplified once-through setup and later employed a H(sub 2)CO(sub 2) recycling system to improve process efficiency. This presentation and paper will cover (1) the design and selection of major hardware items, such as the cryocoolers, pumps, tanks, chillers, and membrane separators, (2) the determination of the optimal cold head design and flow rates needed to meet the collection requirement of 88 g CO(sub 2) hr for 14 hr, (3) the testing of the CO(sub 2) freezer subsystem, and (4) the integration and testing of the two subsystems to verify the desired production rate of 31.7 g CH(sub 4) hr and 71.3 g H(sub 2)O hr along with verification of their purity. The resulting 2.22 kg of CH(sub 2)O(sub 2) propellant per 14 hr day (including O(sub 2) from electrolysis of water recovered from regolith, which also supplies the H(sub 2) for methanation) is of the scale needed for a Mars Sample Return mission. In addition, the significance of the project to NASAs new Mars exploration plans will be discussed.

  13. Atmospheric Processing Module for Mars Propellant Production

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony C.

    2014-01-01

    The multi-NASA center Mars Atmosphere and Regolith COllectorPrOcessor for Lander Operations (MARCO POLO) project was established to build and demonstrate a methaneoxygen propellant production system in a Mars analog environment. Work at the Kennedy Space Center (KSC) Applied Chemistry Laboratory is focused on the Atmospheric Processing Module (APM). The purpose of the APM is to freeze carbon dioxide from a simulated Martian atmosphere containing the minor components nitrogen, argon, carbon monoxide, and water vapor at Martian pressures (8 torr) by using dual cryocoolers with alternating cycles of freezing and sublimation. The resulting pressurized CO(sub 2) is fed to a methanation subsystem where it is catalytically combined with hydrogen in a Sabatier reactor supplied by the Johnson Space Center (JSC) to make methane and water vapor. We first used a simplified once-through setup and later employed a H(sub 2)CO(sub 2) recycling system to improve process efficiency. This presentation and paper will cover (1) the design and selection of major hardware items, such as the cryocoolers, pumps, tanks, chillers, and membrane separators, (2) the determination of the optimal cold head design and flow rates needed to meet the collection requirement of 88 g CO(sub 2) hr for 14 hr, (3) the testing of the CO(sub 2) freezer subsystem, and (4) the integration and testing of the two subsystems to verify the desired production rate of 31.7 g CH(sub 4) hr and 71.3 g H(sub 2)O hr along with verification of their purity. The resulting 2.22 kg of CH(sub 2)O(sub 2) propellant per 14 hr day (including O(sub 2) from electrolysis of water recovered from regolith, which also supplies the H(sub 2) for methanation) is of the scale needed for a Mars Sample Return mission. In addition, the significance of the project to NASAs new Mars exploration plans will be discussed.

  14. Liquid cement premix for improved abandonment and workover operations

    SciTech Connect

    Rae, P.; Johnston, N.

    1996-12-31

    Many cementing operations, such as well abandonment, work-over, etc., incur logistical, personnel and operational problems, and costs, disproportionate to the size of the cementing operation. A typical example being offshore well abandonment on a platform which has limited accommodation, no conventional cementing equipment, and where access, space or weight restrictions preclude its installation. This paper outlines the problems of abandonment and remote locations; it describes the concept, laboratory development, pilot testing, introduction and field use of a liquid cement premix. This novel approach helps reduce waste and minimize the environmental impact of the cementing operation and may be particularly suitable where small volumes of accurately mixed slurry are required, for example in coil tubing applications. It is, however, equally applicable for large volumes since the process lends itself to automation. The technique offers radical changes to cementing operations and equipment requirements, and direct savings to the operator through reduction in the costs of personnel, equipment mobilization, transport, installation, and material wastage.

  15. Coupled X-ray Microtomography Imaging and Computational Fluid Dynamics Modeling for Evaluation of Wellbore Cement Fracture Evolution

    NASA Astrophysics Data System (ADS)

    Jung, H.; Kabilan, S.; Carson, J.; Kuprat, A.; Um, W.; Carroll, K. C.; Bonneville, A.; Fernandez, C.

    2013-12-01

    Composite Portland cement-basalt caprock cores with fractures, as well as neat Portland cement columns, were prepared to understand the geochemical and geomechanical effects on the integrity of wellbores with defects during geologic carbon sequestration. The samples were reacted with CO2-saturated groundwater at 50 degrees Celsius and 10 MPa for 3 months under static conditions, while one cement-basalt core was subjected to mechanical stress at 2.7 MPa before the CO2 reaction. X-ray microtomography (XMT) provided three-dimensional (3-D) visualization of the opening and interconnection of cement fractures due to mechanical stress. Computational fluid dynamics (CFD) modeling further revealed that this stress led to the increase in fluid flow and hence permeability. After the CO2-reaction, XMT images displayed that calcium carbonate precipitation occurred extensively within the fractures in the cement matrix, but only partially along the fracture located at the cement-basalt interface. The 3-D visualization and CFD modeling also showed that the precipitation of calcium carbonate within the cement fractures after the CO2-reaction resulted in the opening of fractures due to crystallization-induced pressure, as well as disconnection of cement fractures and permeability decrease. The permeability calculated based on CFD modeling was in agreement with the experimentally determined permeability. The study also suggests that in deep geological reservoirs the geochemical and geomechanical processes have coupled effects on the fracture evolution and fluid flow. Finally, it is important to emphasize that XMT imaging coupled with CFD modeling represents a powerful tool to visualize and quantify fracture evolution and permeability in geologic materials and predict their behavior during geologic carbon sequestration or hydraulic fracturing for shale gas production and enhanced geothermal system.

  16. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2003-07-31

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report discusses testing that was performed for analyzing the alkali-silica reactivity of ULHS in cement slurries. Laboratory testing during the eleventh quarter focused on evaluation of the alkali-silica reaction of eight different cement compositions, four of which contain ULHS. This report provides a progress summary of ASR testing. The original laboratory procedure for measuring set cement expansion resulted in unacceptable erosion of the test specimens. In subsequent tests, a different expansion procedure was implemented and an alternate curing method for cements formulated with TXI Lightweight cement was employed to prevent sample failure caused by thermal shock. The results obtained with the modified procedure showed improvement over data obtained with the original procedure, but data for some compositions were still questionable. Additional modification of test procedures for compositions containing TXI Lightweight cement were implemented and testing is ongoing.

  17. PRODUCTION OF CARBON PRODUCTS USING A COAL EXTRACTION PROCESS

    SciTech Connect

    Dady Dadyburjor; Chong Chen; Elliot B. Kennel; Liviu Magean; Peter G. Stansberry; Alfred H. Stiller; John W. Zondlo

    2005-12-12

    The purpose of this DOE-funded effort is to develop technologies for carbon products from coal-derived feed-stocks. Carbon products can include precursor materials such as solvent extracted carbon ore (SECO) and synthetic pitch (Synpitch). In addition, derived products include carbon composites, fibers, foams and others.

  18. Feasibility of disposing waste glyphosate neutralization liquor with cement rotary kiln.

    PubMed

    Bai, Y; Bao, Y B; Cai, X L; Chen, C H; Ye, X C

    2014-08-15

    The waste neutralization liquor generated during the glyphosate production using glycine-dimethylphosphit process is a severe pollution problem due to its high salinity and organic components. The cement rotary kiln was proposed as a zero discharge strategy of disposal. In this work, the waste liquor was calcinated and the mineralogical phases of residue were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The mineralogical phases and the strength of cement clinker were characterized to evaluate the influence to the products. The burnability of cement raw meal added with waste liquor and the calorific value of waste liquor were tested to evaluate the influence to the thermal state of the kiln system. The results showed that after the addition of this liquor, the differences of the main phases and the strength of cement clinker were negligible, the burnability of raw meal was improved; and the calorific value of this liquor was 6140 J/g, which made it could be considered as an alternative fuel during the actual production. PMID:25010454

  19. Process management applications in biopharmaceutical drug production

    E-print Network

    Smith, Stephen E

    2011-01-01

    Genzyme's manufacturing and supply chain organization is responsible for the production and delivery of medically necessary medicines for patients with rare diseases around the world. Because of the nature of the products ...

  20. Development of an advanced continuous mild gasification process for the production of co-products. Quarterly report, January--March, 1996

    SciTech Connect

    O`Neal, G.W.

    1996-04-01

    Determination of the best furnace for a commercial coke plant is underway. A shuttle or tunnel kiln has economic advantage over a rotary hearth design. Production of 20 tons of coke in a small shuttle kiln is near completion which will provide experience for this design. Twenty tons of CTC continuous coke are being produced for testing at a General Motors` foundry. The production is approximately 75 percent complete. During this production, variables of the process are being studied to aid in design of a commercial coke plant. Raw material composition, blending, briquetting variables, and calcining heat profile are the major areas of interest. Western SynCoal Company produces a dried coal product from sub-bituminous coal. This upgraded product was evaluated for producing coke products by blending char from this coal product with the coal product along with suitable binders. The green briquettes were then calcined to produce coke. The resulting coke was judged to be usable as part of a cupola coke charge or as a fuel in cement kilns and sugar beet furnaces.

  1. Optimizing the Product Derivation Process School of EECS

    E-print Network

    Erwig, Martin

    is widely used in software product-line engineering to capture the commonalities and variabilities within. INTRODUCTION Software product lines (SPLs) are increasingly employed in the software development process since shows the feature model for a simple mobile phone product line. The second process involves

  2. 40 CFR 158.330 - Description of production process.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Description of production process. 158.330 Section 158.330 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.330 Description of production process....

  3. 40 CFR 158.330 - Description of production process.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Description of production process. 158.330 Section 158.330 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.330 Description of production process....

  4. 40 CFR 158.330 - Description of production process.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Description of production process. 158.330 Section 158.330 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.330 Description of production process....

  5. A Prevalidation of the Product-Process Matrix

    ERIC Educational Resources Information Center

    Ashenbaum, Bryan

    2013-01-01

    A major challenge for instructors of supply chain and operations management (SCOM) courses is to help students who have never seen a production floor visualize concepts, such as the product-process matrix from standard introductory SCOM texts. This article presents a classroom exercise, which "prevalidates" the product-process matrix.…

  6. 40 CFR 158.330 - Description of production process.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Description of production process. 158.330 Section 158.330 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.330 Description of production process....

  7. Enamel corrosion produced by zinc phosphate dental cement.

    PubMed

    Abramovich, A; Macchi, R L; Ribas, L M

    1976-01-01

    The application of a phosphoric acid solution or of a zinc phosphate cement mix on enamel surface causes alteration of its structure. The lesions of the enamel are cavities of irregular shapes that might retain debris. In view of the high solubility of disintegration of the cement, those cavities can be considered potential sites of plaque installation and initiation of carious processes. PMID:1060643

  8. Process reengineering for the product development process at an analytical instrument manufacturer

    E-print Network

    Tandon, Shubhang

    2014-01-01

    In an analytical instrument manufacturing company, the new product development process was analyzed with the objective of reducing time to market, to full scale production of new products and to improve project management ...

  9. Multi-Spectral Analysis Of Frying Processes For Meat Products

    E-print Network

    Multi-Spectral Analysis Of Frying Processes For Meat Products Søren Blond Daugaard Kongens Lyngby properties in relation to the frying process of various meat products, using multi-spectral imaging process for meat using multi-spectral vision technology. The project examines the possibility of creating

  10. Work Structuring to Achieve Integrated ProductProcess Design

    E-print Network

    Tommelein, Iris D.

    Work Structuring to Achieve Integrated Product­Process Design Cynthia C. Y. Tsao, A.M.ASCE1 ; Iris presents "work structuring," a term used to describe the effort of integrating product and process design throughout the project development process. To illustrate current work structuring practice, we describe

  11. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Frozen processed food... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the...

  12. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Frozen processed food... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the...

  13. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Frozen processed food... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the...

  14. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Frozen processed food... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the...

  15. 48 CFR 870.111-5 - Frozen processed food products.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Frozen processed food... DEPARTMENT SUPPLEMENTARY REGULATIONS SPECIAL PROCUREMENT CONTROLS Controls 870.111-5 Frozen processed food products. (a) The following frozen processed food products must have a label complying with the...

  16. From Sentence Production to Text Production: Investigating Fundamental Processes.

    ERIC Educational Resources Information Center

    Fayol, Michel

    1991-01-01

    Presents a review of cognitive psychology research dealing with the organization and functioning of oral and written language production mechanisms. Discusses works dealing with the microstructural aspects of language, primarily oral production. Describes how the research perspective has evolved from modular to connectionist models. Examines the…

  17. Next generation enhancement of cements by the addition of industrial wastes and subsequent treatment with supercritical CO{sub 2}

    SciTech Connect

    Taylor, C.M.V.; Rubin, J.B.; Carey, J.W.; Jones, R.; Baglin, F.G.

    1997-09-01

    The natural curing reactions which occur in a standard portland cement involve the formation of portlandite, Ca(OH){sub 2}, and calcium silicate hydrates, CSH. Over time, the cured cement abstracts carbon dioxide, CO{sub 2}, from the air, converting the portlandite and CSH to calcium carbonate, CaCO{sub 3}. It turns out, however, that this secondary conversion results in the blockage and/or closure of pores, drastically slowing the reaction rate with time. By exposing a portland cement to supercritical CO{sub 2} (SCCO{sub 2}), it is found that the carbonation reaction can be greatly accelerated. This acceleration is due to (1) the ability of the supercritical fluid to penetrate into the pores of the cement, providing continuous availability of fresh reactant, in hyper-stoichiometric concentrations; and (2) the solubility of the reaction product in the supercritical fluid, facilitating its removal. By accelerating the natural aging reactions, a chemically stable product is formed having reduced porosity, permeability and pH, while at the same time significantly enhancing the mechanical strength. The supercritical CO{sub 2} treatment process also removes a majority of the hydrogenous material from the cement, and sequesters large amounts of carbon dioxide, permanently removing it from the environment. The authors describe the general features of supercritical fluids, as well as the application of these fluids to the treatment of cements containing industrial waste. Some of the issues concerning the economic feasibility of industrial scale-up will be addressed. Finally, some initial results of physical property measurements made on portland cements before and after supercritical fluid CO{sub 2} treatment will be presented.

  18. From Rocks to Cement. What We Make. Science and Technology Education in Philippine Society.

    ERIC Educational Resources Information Center

    Philippines Univ., Quezon City. Science Education Center.

    This module deals with the materials used in making concrete hollow blocks. Topics discussed include: (1) igneous, metamorphic, and sedimentary rocks; (2) weathering (the process of breaking down rocks) and its effects on rocks; (3) cement; (4) stages in the manufacturing of Portland cement; and (5) the transformation of cement into concrete…

  19. Materials of Cement Science Primer Principal Investigators: Professors Hamlin Jennings and Jeffery

    E-print Network

    Materials of Cement Science Primer Principal Investigators: Professors Hamlin Jennings and Jeffery Chapter 3. The Concrete Construction Process 19 Chapter 4. Manufacture and composition of Portland cement 24 Chapter 5. Hydration and microstructure of Portland cement paste 45 Chapter 6. The pore structure

  20. Electric polarization and depolarization in cement-based materials, studied by apparent electrical resistance measurement

    E-print Network

    Chung, Deborah D.L.

    in carbon fiber cement, due to the fast hole response. Sand addition slowed down polarization saturation of polarization reversal in carbon-fiber-reinforced cement [1]. Subsequent to polarization, reversal addressed these processes in carbon-fiber- reinforced cement only [1]. The subject pertains to the movement

  1. Method for cementing a well

    SciTech Connect

    Allen, T.E.

    1992-04-14

    This patent describes a method of performing a cement job on a well so that a cement slurry is made and placed in the well, it comprises: flowing cement and water through a mixer into a tub to provide a first body of cement slurry; flowing a portion of the first body of cement slurry into a displacement tank to provide a second body of cement slurry; flowing the second body of cement slurry from the displacement tank into the well; flowing displacement fluid into the displacement tank; and flowing displacement fluid from the displacement tank into the well behind the cement slurry to place the cement slurry at a desired location in the well.

  2. PRODUCTION OF CARBON PRODUCTS USING A COAL EXTRACTION PROCESS

    SciTech Connect

    Dady Dadyburjor; Chong Chen; Elliot B. Kennel; Liviu Magean; Peter G. Stansberry; Alfred H. Stiller; John W. Zondlo

    2006-02-23

    The purpose of this DOE-funded effort is to develop technologies for carbon products from coal-derived feedstocks. Carbon products can include precursor materials such as solvent extracted carbon ore (SECO) and synthetic pitch (Synpitch). In addition, derived products include carbon composites, fibers, foams and others. Key milestones included producing hydrogenated coal in the Hydrotreating Facility for the first time. The facility is now operational, although digital controls have not yet been completely wired. In addition, ultrasound is being used to investigate enhanced dissolution of coal. Experiments have been carried out.

  3. Process for the production of phthalic anhydride

    SciTech Connect

    Miserlis, C. D.

    1984-03-06

    A system for producing phthalic anhydride by the catalytic oxidation of nathphalene, wherein without creating a significant pressure drop in the system substantially aff of the catalyst particles are removed from the product stream before the product stream is sent to a battery of switch condensers for recovery of the phthalic anhydride.

  4. Hydrogen in the Methanol Production Process

    ERIC Educational Resources Information Center

    Kralj, Anita Kovac; Glavic, Peter

    2006-01-01

    Hydrogen is a very important industrial gas in chemical processes. It is very volatile; therefore, it can escape from the process units and its mass balance is not always correct. In many industrial processes where hydrogen is reacted, kinetics are often related to hydrogen pressure. The right thermodynamic properties of hydrogen can be found for…

  5. Materials Processing and Product Fabrication Course Description

    E-print Network

    Processes 4.1 VP (CVD/PVD) 4.2 P/M 4.3 3D Printing 4. Process Kinetics 3.1 Nature of Materials 3.2 Phase, September 14 Welding/P/M/VP Process Demo. 5 Wednesday, September 16 Machining/3D Printing Demo. 6 Monday

  6. Productive Skills for Process Operatives. Skills Review.

    ERIC Educational Resources Information Center

    Giles, L.; Kodz, J.; Evans, C.

    A study of process operatives examined the developments in processing work in 20 organizations within the chemical and food and drink processing industries. Seven exploratory interviews were followed by 20 employer interviews. Technological innovations caused job losses and layoffs. Organizational responses adopted to meet increasing competitive…

  7. Powder-Metallurgy Process And Product

    NASA Technical Reports Server (NTRS)

    Paris, Henry G.

    1988-01-01

    Rapid-solidification processing yields alloys with improved properties. Study undertaken to extend favorable property combinations of I/M 2XXX alloys through recently developed technique of rapid-solidification processing using powder metallurgy(P/M). Rapid-solidification processing involves impingement of molten metal stream onto rapidly-spinning chill block or through gas medium using gas atomization technique.

  8. Novel cationic-modified salep as an efficient flocculating agent for settling of cement slurries.

    PubMed

    Pourjavadi, Ali; Fakoorpoor, Seyed Mahmoud; Hosseini, Seyed Hassan

    2013-04-01

    A new cationic flocculant was synthesized by graft copolymerization of acrylamide (AM) and 3-(methacryloylamino)propyl]trimethylammonium chloride (MAPTAC) onto salep using free radical polymerization initiated by ammonium persulfate (APS) to produce cationic salep [S-g-P(AM-co-MAPTAC)]. Reaction parameters (monomers/salep ratio, concentration of reactants, MAPTAC/AM ratio, and APS) were optimized using a full factorial experimental design to obtain the highest settling rate for cement suspensions. The best performing product was characterized by gel permeation chromatography (GPC), FTIR, (1)H NMR spectroscopy, and thermogravimetric analysis (TGA). The resulted cationic flocculant may be introduced as a promising candidate for the green production of asbestos-free fiber cement products by Hatschek process. PMID:23499090

  9. MAINTAINING SOIL PROCESSES FOR PLANT PRODUCTIVITY AND COMMUNITY DYNAMICS

    EPA Science Inventory

    Rangeland soil biota affect soil properties and processes that control the availability of water and nutrients that are essential for the maintenance of productivity and vegetation composition. oil processes mediated by soil biota include decomposition, nutrient immobilization an...

  10. A process for improving long-term production planning

    E-print Network

    McIntosh, Timothy, Jr. (Timothy P.)

    2011-01-01

    This project presents improvements to the business process used to generate the Sikorsky five-year production scheduling plan that is a central coordinating process for company operations. Recommendations will improve the ...

  11. Development of a Laboratory Cement Quality Analysis Apparatus Based on Laser-Induced Breakdown Spectroscopy

    NASA Astrophysics Data System (ADS)

    Fan, Juanjuan; Zhang, Lei; Wang, Xin; Li, Yufang; Gong, Yao; Dong, Lei; Ma, Weiguang; Yin, Wangbao; Wang, Zhe; Li, Zheng; Zhang, Xiangjie; Li, Yi; Jia, Suotang

    2015-11-01

    Determination of the chemical composition of cement and ratio values of clinker plays an important role in cement plants as part of the optimal process control and product quality evaluation. In the present paper, a laboratory laser-induced breakdown spectroscopy (LIBS) apparatus mainly comprising a sealed optical module and an analysis chamber has been designed for possible application in cement plants for on-site quality analysis of cement. Emphasis is placed on the structure and operation of the LIBS apparatus, the sealed optical path, the temperature controlled spectrometer, the sample holder, the proper calibration model established for minimizing the matrix effects, and a correction method proposed for overcoming the ‘drift’ obstacle. Good agreement has been found between the laboratory measurement results from the LIBS method and those from the traditional method. The absolute measurement errors presented here for oxides analysis are within 0.5%, while those of ratio values are in the range of 0.02 to 0.05. According to the obtained results, this laboratory LIBS apparatus is capable of performing reliable and accurate, composition and proximate analysis of cement and is suitable for application in cement plants. supported by National Natural Science Foundation of China (Nos. 61127017, 61378047, 61205216, 61178009, 61108030, 61475093, and 61275213), the National Key Technology R&D Program of China (No. 2013BAC14B01), the 973 Program of China (No. 2012CB921603), the Shanxi Natural Science Foundation, China (Nos. 2013021004-1, 2012021022-1), and the Shanxi Scholarship Council of China (Nos. 2013-011 and 2013-01)

  12. Processing maize flour and corn meal food products

    PubMed Central

    Gwirtz, Jeffrey A; Garcia-Casal, Maria Nieves

    2014-01-01

    Corn is the cereal with the highest production worldwide and is used for human consumption, livestock feed, and fuel. Various food technologies are currently used for processing industrially produced maize flours and corn meals in different parts of the world to obtain precooked refined maize flour, dehydrated nixtamalized flour, fermented maize flours, and other maize products. These products have different intrinsic vitamin and mineral contents, and their processing follows different pathways from raw grain to the consumer final product, which entail changes in nutrient composition. Dry maize mechanical processing creates whole or fractionated products, separated by anatomical features such as bran, germ, and endosperm. Wet maize processing separates by chemical compound classification such as starch and protein. Various industrial processes, including whole grain, dry milling fractionation, and nixtamalization, are described. Vitamin and mineral losses during processing are identified and the nutritional impacts outlined. Also discussed are the vitamin and mineral contents of corn. PMID:24329576

  13. Importance of granulometry on phase evolution and phase-to-phase relationships of experimentally burned impure limestones intended for production of hydraulic lime and/or natural cement

    NASA Astrophysics Data System (ADS)

    Kozlovcev, Petr; P?ikryl, Richard; P?ikrylová, Ji?ina

    2015-04-01

    In contrast to modern ordinary Portland cement production from finely ground raw material blends, ancient burning of hydraulic lime was conducted by burning larger pieces of natural raw material. Due to natural variability of raw material composition, exploitation of different beds from even one formation can result the product with significantly different composition and/or properties. Prague basin (Neoproterozoic to pre-Variscan Palaeozoic of the central part of the Bohemian Massif - the so-called Barrandian area, Czech Republic) represents a classical example of the limestone-rich region with long-term history of limestone burning for quick lime and/or various types of hydraulic binders. Due to the fact that burning of natural hydraulic lime has been abandoned in this region at the turn of 19th/20th c., significant gap in knowledge on the behavior of various limestone types and on the influence of minor variance in composition on the quality of burned product is encountered. Moreover, the importance of employment of larger pieces of raw material for burning for the development of proper phase-to-phase relationships (i.e. development of hydraulic phases below sintering temperature at mutual contacts of minerals) has not been examined before. To fill this gap, a representative specimens of major limestone types from the Prague basin have been selected for experimental study: Upper Silurian limestone types (P?ídolí and Kopanina Lms.), and Lower Devonian limestones (Radotín, Kotýs, ?eporyje, Dvorce-Prokop, and Zlíchov Lms.). Petrographic character of the experimental material was examined by polarizing microscopy, cathodoluminescence, scanning electron microscopy with an energy dispersive spectrometer (SEM-EDS), and X-ray diffraction (XRD) of insoluble residue. Based on the data from wet silicate analyses, modal composition of studied impure limestones was computed. Experimental raw material was burned in laboratory electric furnace at 1000 and 1200°C for 3 and/or 6 hours. Burned samples were examined by XRD for phase composition and by SEM-EDS for phase-to-phase relationships due to the burning. Based on our data it is evident that larnite-belite (dicalcium-silicate) is dominant phase in burned silica-rich limestones (represented by e.g. Dvorce-Prokop, P?ídolí and/or Kopanina Lms.). In clay-rich limestones containing kaolinite and illite, gehlenite and other calcium aluminates and aluminosilicates were detected (represented by Koso?, ?eporyje, and/or a portion of Dvorce-Prokop Lms.). Due to higher proportion of Fe-oxihydroxides in the ?eporyje Lms., brownmillerite (calcium aluminoferrite) forms as a typical minor phases during burning. Free-lime (plus its hydrated form - portlandite) makes dominant phase in limestones exhibiting low non-carbonate admixture (Kotýs and/or a portion of Kopanina Lms.). These results clearly demonstrate that presence of certain non-carbonate minerals governs formation of certain hydraulic phases in burned product, whilst mutual proportions of individual minerals in raw materials influence amount of newly formed phases.

  14. Radon emanation from concrete and the influence of using flyash in cement.

    PubMed

    van der Lugt, G; Scholten, L C

    1985-10-01

    In the Netherlands both Portland cement and blast furnace cement (slags from blast furnaces with about 30% Portland cement) are used for concrete. Radon exhalation measurements were carried out on concrete blocks made with these two types of cement and blocks with 15, 25 and 35% of the cement substituted by three different types of flyash. The results show that substituting part of the cement by flyash has no drastic effect on the exhalation rate. For concrete with Portland cement the exhalation rate decreases using flyash with an average radium content. With blast furnace cement a slight increase may be expected. The exhalation of concrete is greater than the sum of the exhalation values of the constituting components. The water in the pores of the concrete plays an essential role in the emanation process. PMID:3853271

  15. Process Integration Issues in Biofuels Production

    E-print Network

    Ahrendt, Wolfgang

    of route - Low temperature fermentation of sugars - High temperature gasification followed by syngas it. 8 #12;Fermentation processes · It is instructive to look at the numbers for real processes. Let's look first at fermentation to produce ethanol. - C6H12O6 2 C2H5OH + 2 CO2 DH = -67.7 kJ/mol DG = -228

  16. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2003-06-16

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report discusses testing that was performed for analyzing the alkali-silica reactivity of ULHS in cement slurries. Laboratory testing during the tenth quarter focused on evaluation of the alkali-silica reaction of eight different cement compositions, four of which contain ULHS. The original laboratory procedure for measuring set cement expansion resulted in test specimen erosion that was unacceptable. A different expansion procedure is being evaluated. This report provides a progress summary of ASR testing. The testing program initiated in November produced questionable initial results so the procedure was modified slightly and the testing was reinitiated. The results obtained with the modified procedure showed improvement over data obtained with the original procedure, but questionable data were obtained from several of the compositions. Additional modification of test procedures for compositions containing TXI Lightweight cement are being implemented and testing is ongoing.

  17. ULTRA-LIGHTWEIGHT CEMENT

    SciTech Connect

    Fred Sabins

    2001-10-23

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). Work reported herein addresses tasks performed in the fourth quarter as well as the other three quarters of the past year. The subjects that were covered in previous reports and that are also discussed in this report include: Analysis of field laboratory data of active cement applications from three oil-well service companies; Preliminary findings from a literature review focusing on problems associated with ultra-lightweight cements; Summary of pertinent information from Russian ultra-lightweight cement literature review; and Comparison of compressive strengths of ULHS systems using ultrasonic and crush methods Results reported from the fourth quarter include laboratory testing of ULHS systems along with other lightweight cement systems--foamed and sodium silicate slurries. These comparison studies were completed for two different densities (10.0 and 11.5 lb/gal) and three different field application scenarios. Additional testing included the mechanical properties of ULHS systems and other lightweight systems. Studies were also performed to examine the effect that circulation by centrifugal pump during mixing has on breakage of ULHS.

  18. Lightweight cementing program increases profit from Kansas oil field

    SciTech Connect

    McCalmont, A.J. ); Matthews, B.; Crook, R. )

    1992-06-29

    This paper reports that single-stage, lightweight cementing in a Kansas operation improved the cement bond across a permeable oil/water sand. Additionally, pipe movement after pumping helped bond quality by preventing the slurry from beginning its transition time. This delay allowed continued transmission of hydrostatic pressure against the formation. In 1991, OXY USA Inc. completed 12 wells in the Ray field in Kansas. All wells were drilled to the Reagan sand. The sand has a distinct water/oil contact, strong water drive, and good permeability. Because of poor cement bonding across the Reagan, two-stage conventional cementing in the first eight wells did not effectively prevent excessive water production. Some of these wells had to have remedial cement squeezes and be reperforated. This work increased completion costs by about $15,000/well.

  19. Set retarded cement compositions and well cementing methods

    SciTech Connect

    Childs, J.D.; Sabins, F.L.

    1986-04-15

    This patent describes a method of cementing a subterranean zone penetrated by a well bore comprising: providing a set retarded aqueous hydraulic cement slurry; admixing with the cement slurry to enhance the compressive strength development thereof after placement, an effective amount of a delayed retarder neutralizer selected from the group consisting of: a triethanolamine titanium chelate.

  20. New technology eliminates bulking in cementing operations

    SciTech Connect

    Anderson, J.W.; Buchanan, A.I.; Susanto, A.

    1996-12-31

    For years the drilling industry has wrestled with the problems associated with well cementing. The introduction of pneumatic bulk systems increased cement slurry mixing rates but accurate density control still eluded the experts. Many companies have introduced process controlled mixing systems but these are both expensive and not totally reliable. A new cementing system, that does not rely on bulking, has become available to the industry a storable oilwell cement slurry that can be kept in a liquid state indefinitely and made to set as and when required. Operators in Indonesia are now benefiting from this new technology. Slurries are mixed and tested to ensure they meet design specifications well before they are required on site. The {open_quotes}Base Slurry{close_quotes} or {open_quotes}Liquid Cement Premix{close_quotes} (LCP), which typically has a density of 16.0 pounds per gallon (ppg), is transported to the rig, diluted to produce the required density and pumped, ensuring a homogeneous slurry from start to finish.

  1. Fe-containing phases in hydrated cements

    SciTech Connect

    Dilnesa, B.Z.; Wieland, E.; Lothenbach, B.; Dähn, R.; Scrivener, K.L.

    2014-04-01

    In this study synchrotron X-ray absorption spectroscopy (XAS) has been applied, an element specific technique which allows Fe-containing phases to be identified in the complex mineral mixture of hydrated cements. Several Fe species contributed to the overall Fe K-edge spectra recorded on the cement samples. In the early stage of cement hydration ferrite was the dominant Fe-containing mineral. Ferrihydrite was detected during the first hours of the hydration process. After 1 day the formation of Al- and Fe-siliceous hydrogarnet was observed, while the amount of ferrihydrite decreased. The latter finding agrees with thermodynamic modeling, which predicts the formation of Fe-siliceous hydrogarnet in Portland cement systems. The presence of Al- and Fe-containing siliceous hydrogarnet was further substantiated in the residue of hydrated cement by performing a selective dissolution procedure. - Highlights: • Fe bound to ferrihydrite at early age hydration • Fe found to be stable in siliceous hydrogarnet at longer term age hydration • Fe-containing AFt and AFm phases are less stable than siliceous hydrogarnet. • The study demonstrates EXAFS used to identify amorphous or poorly crystalline phases.

  2. Product-Process Distinctions in ELT Curriculum Theory and Practice

    ERIC Educational Resources Information Center

    Wette, Rosemary

    2011-01-01

    ELT theory classifies curricula as belonging to one of two contrasting approaches: either process or product. While foundation-level teacher education literature offers strongly product-oriented advice, research- and theory-oriented texts stress the need to negotiate with learners, and to take language-learning processes into account. This article…

  3. Collective effects in multiparticle production processes at the LHC

    E-print Network

    S. M. Troshin; N. E. Tyurin

    2011-06-27

    We discuss various aspects of the multiparticle production processes at the LHC energy range with emphasis on the collective effects associated with appearance of the new scattering mode, which corresponds to the reflective scattering and its impact on multiparticle production processes.

  4. The Interaction between Central and Peripheral Processes in Handwriting Production

    ERIC Educational Resources Information Center

    Roux, Sebastien; McKeeff, Thomas J.; Grosjacques, Geraldine; Afonso, Olivia; Kandel, Sonia

    2013-01-01

    Written production studies investigating central processing have ignored research on the peripheral components of movement execution, and vice versa. This study attempts to integrate both approaches and provide evidence that central and peripheral processes interact during word production. French participants wrote regular words (e.g. FORME),…

  5. "Key Moments" as Pedagogical Windows into the Video Production Process

    ERIC Educational Resources Information Center

    Halverson, Erica; Gibbons, Damiana

    2010-01-01

    In this article, we trace learning across the digital video production process through case studies with four youth media arts organizations (YMAOs) across the United States. We hypothesize that what these organizations share is a series of key moments throughout the production process in which youth must articulate the relationship between the…

  6. Nonperturbative multiphoton processes and electron-positron pair production

    SciTech Connect

    Hatsagortsyan, K. Z.; Mueller, C.; Keitel, C. H.

    2006-04-07

    Various regimes of pair production in laser fields are analyzed. Particularly, the question of the observability of pair production in a nonperturbative multiphoton regime is discussed. A simple heuristic method is employed which gives order-of-magnitude estimates for probabilities of multiphoton processes and allows to describe its main features. The method is initially probed upon the known process of pair production in a Coulomb and a strong laser field. Then it is applied to the nonperturbative multiphoton regime of the pair production process in a standing laser wave.

  7. Pharmaceutical tablet compaction : product and process design

    E-print Network

    Pore, Mridula

    2009-01-01

    This thesis explores how tablet performance is affected by microstructure, and how microstructure can be controlled by selection of excipients and compaction parameters. A systematic strategy for formulation and process ...

  8. Integrated coke, asphalt and jet fuel production process and apparatus

    DOEpatents

    Shang, Jer Y. (McLean, VA)

    1991-01-01

    A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale and tar sands.

  9. 9 CFR 318.306 - Processing and production records.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Processing and production records. 318.306 Section 318.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... retort operation. Container conveyor speed, and for agitating hydrostatic retorts, the rotative...

  10. 9 CFR 381.306 - Processing and production records.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Processing and production records. 381.306 Section 381.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF.... Container conveyor speed, and for agitating hydrostatic retorts, the rotative chain speed, shall...

  11. Ethanol and other products from citrus processing waste

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Greater than 80 percent of citrus produced in Florida is processed for juice production. The bulk of this waste material is dried as citrus pulp and sold as a cattle feed by-product, often at a price lower than the cost of production. While not profitable, this does solve the problem of waste dispos...

  12. 9 CFR 381.306 - Processing and production records.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Processing and production records. 381.306 Section 381.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF.... Container conveyor speed, and for agitating hydrostatic retorts, the rotative chain speed, shall...

  13. 9 CFR 381.306 - Processing and production records.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Processing and production records. 381.306 Section 381.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF.... Container conveyor speed, and for agitating hydrostatic retorts, the rotative chain speed, shall...

  14. 9 CFR 318.306 - Processing and production records.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Processing and production records. 318.306 Section 318.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... retort operation. Container conveyor speed, and for agitating hydrostatic retorts, the rotative...

  15. 9 CFR 318.306 - Processing and production records.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Processing and production records. 318.306 Section 318.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... retort operation. Container conveyor speed, and for agitating hydrostatic retorts, the rotative...

  16. 9 CFR 381.306 - Processing and production records.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Processing and production records. 381.306 Section 381.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF.... Container conveyor speed, and for agitating hydrostatic retorts, the rotative chain speed, shall...

  17. 9 CFR 318.306 - Processing and production records.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Processing and production records. 318.306 Section 318.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... retort operation. Container conveyor speed, and for agitating hydrostatic retorts, the rotative...

  18. 9 CFR 381.306 - Processing and production records.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Processing and production records. 381.306 Section 381.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF.... Container conveyor speed, and for agitating hydrostatic retorts, the rotative chain speed, shall...

  19. 9 CFR 318.306 - Processing and production records.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Processing and production records. 318.306 Section 318.306 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... retort operation. Container conveyor speed, and for agitating hydrostatic retorts, the rotative...

  20. Production Goals Process: Means and End

    ERIC Educational Resources Information Center

    Leske, Gary W.

    1974-01-01

    To remain educationally accountable, agriculture instructors must use production enterprises whenever they are available, exploiting their potential for facilitating the development of students' decision-making abilities through management practices, presented here in sequential development (student-set goals, standards, records, record analyses,…

  1. Development of fluidized bed cement sintering technology

    SciTech Connect

    Mukai, Katsuji

    1994-12-31

    In the new system presented in this paper, the cement clinker is sintered, not in a rotary kiln, but in two different furnaces: a spouted bed kiln and a fluidized bed kiln. The heat generated in the process of cooling the cement clinker is recovered by a fluidized bed cooler and a packed bed cooler, which are more efficient than the conventional coolers. Compared with the rotary kiln system, the new technology significantly reduces NO{sub x} emissions, appreciably cuts energy consumption, and reduces CO{sub 2} emissions as well. Thus, the new system is an efficient cement sintering system that is friendly to the global environment. In this paper, we describe this new technology as one of the applied technologies at an industrial level that is being developed in the Clean Coal Technology Project, and we present the results from test operations at our pilot plant.

  2. Use of iodized salt in processed Philippine food products.

    PubMed

    Azanza, P; Cariaso, K; Dela Cerna, M C; de Ocampo, C; Galvez, F; Moises, M; Pujanes, K

    1998-06-01

    The effects of iodized salt use on the quality of processed Philippine food products were evaluated. Samples for the study included dried-salted and smoked fish products, nitrite-cured pork, and fermented plain and flavored shrimp pastes. Generally, no significant differences were detected between the physicochemical, microbiological and sensory characteristics of the test products prepared with iodized and unfortified NaCl salts. The salting process in each food operation significantly increased the iodine content of the test products. However, subsequent losses in the absorbed iodine were recorded due to the boiling, smoking, drying, fermenting and heating processes in the different operations. It was recommended that studies be undertaken on the addition of iodine to semi-processed or completely processed food products to lessen iodine losses. PMID:24393638

  3. Recycling of ladle slag in cement composites: Environmental impacts.

    PubMed

    Serjun, Vesna Zalar; Mladenovi?, Ana; Mirti?, Breda; Meden, Anton; Š?an?ar, Janez; Mila?i?, Radmila

    2015-09-01

    In the present work compact and ground cement composites in which 30% of cement by mass was replaced by ladle slag were investigated for their chemical and physico-mechanical properties. To evaluate long-term environmental impacts, leachability test based on diffusion, which combined both, diffusion and dissolution of contaminants, was performed in water and saline water. Total element concentrations and Cr(VI) were determined in leachates over a time period of 180days. At the end of the experiment, the mineralogical composition and the physico-mechanical stability of cement composites was also assessed. The results revealed that Cr(III) and Cr(VI) were immobilized by the hydration products formed in the cement composites with the addition of ladle slag. Cr(VI) content originating from the cement was also appreciably reduced by Fe(II) from minerals present in the added ladle slag, which thus had significant positive environmental effects. Among metals, only Mo and Ba were leached in elevated concentrations, but solely in ground cement composites with the addition of ladle slag. Lower V concentrations were observed in leachates of ground than compact composite. It was demonstrated that the presence of ladle slag in cement composites can even contribute to improved mortar resistance. The investigated ladle slag can be successfully implemented in cement composites as supplementary cementitious material. PMID:26008145

  4. Small-particle-size cement

    SciTech Connect

    Ewert, D.P.; Almond, S.W.; Blerhaus, W.M. II )

    1991-05-01

    Successful remedial cementing has historically been difficult in wells with large-interval, multizone, gravel-packed completions. The reason is the inability of conventional oilfield cements to penetrate gravel packs adequately. Small-particle-size cement (SPSC) was developed to penetrate gravel packs and to provide the zonal isolation required. This paper details the laboratory work, job design, and field implementation of this new cement.

  5. Production process for advanced space satellite system cables/interconnects.

    SciTech Connect

    Mendoza, Luis A.

    2007-12-01

    This production process was generated for the satellite system program cables/interconnects group, which in essences had no well defined production process. The driver for the development of a formalized process was based on the set backs, problem areas, challenges, and need improvements faced from within the program at Sandia National Laboratories. In addition, the formal production process was developed from the Master's program of Engineering Management for New Mexico Institute of Mining and Technology in Socorro New Mexico and submitted as a thesis to meet the institute's graduating requirements.

  6. Curing time effect on the fraction of {sup 137}Cs from cement-ion exchange resins-bentonite clay composition

    SciTech Connect

    Plecas, Ilija; Dimovic, Slavko

    2007-07-01

    To assess the safety of disposal of radioactive waste material in cement, curing conditions and time of leaching radionuclides {sup 137}Cs have been studied. Leaching tests in cement-ion exchange resins-bentonite matrix, were carried out in accordance with a method recommended by IAEA. Curing conditions and curing time prior to commencing the leaching test are critically important in leach studies since the extent of hydration of the cement materials determines how much hydration product develops and whether it is available to block the pore network, thereby reducing leaching. Incremental leaching rates R{sub n}(cm/d) of {sup 137}Cs from cement ion exchange resins-bentonite matrix after 180 days were measured. The results presented in this paper are examples of results obtained in a 20-year concrete testing project which will influence the design of the engineer trenches system for future central Serbian radioactive waste storing center. (authors)

  7. Product Binding Varies Dramatically between Processive and Nonprocessive Cellulase Enzymes

    SciTech Connect

    Bu, L.; Nimlos, M. R.; Shirts, M. R.; Stahlberg, J.; Himmel, M. E.; Crowley, M. F.; Beckham, G. T.

    2012-07-13

    Cellulases hydrolyze {beta}-1,4 glycosidic linkages in cellulose, which are among the most prevalent and stable bonds in Nature. Cellulases comprise many glycoside hydrolase families and exist as processive or nonprocessive enzymes. Product inhibition negatively impacts cellulase action, but experimental measurements of product-binding constants vary significantly, and there is little consensus on the importance of this phenomenon. To provide molecular level insights into cellulase product inhibition, we examine the impact of product binding on processive and nonprocessive cellulases by calculating the binding free energy of cellobiose to the product sites of catalytic domains of processive and nonprocessive enzymes from glycoside hydrolase families 6 and 7. The results suggest that cellobiose binds to processive cellulases much more strongly than nonprocessive cellulases. We also predict that the presence of a cellodextrin bound in the reactant site of the catalytic domain, which is present during enzymatic catalysis, has no effect on product binding in nonprocessive cellulases, whereas it significantly increases product binding to processive cellulases. This difference in product binding correlates with hydrogen bonding between the substrate-side ligand and the cellobiose product in processive cellulase tunnels and the additional stabilization from the longer tunnel-forming loops. The hydrogen bonds between the substrate- and product-side ligands are disrupted by water in nonprocessive cellulase clefts, and the lack of long tunnel-forming loops results in lower affinity of the product ligand. These findings provide new insights into the large discrepancies reported for binding constants for cellulases and suggest that product inhibition will vary significantly based on the amount of productive binding for processive cellulases on cellulose.

  8. Respiratory tract mortality in cement workers: a proportionate mortality study

    PubMed Central

    2012-01-01

    Background The evidence regarding the association between lung cancer and occupational exposure to cement is controversial. This study investigated causes of deaths from cancer of respiratory tract among cement workers. Methods The deaths of the Greek Cement Workers Compensation Scheme were analyzed covering the period 1969-1998. All respiratory, lung, laryngeal and urinary bladder cancer proportionate mortality were calculated for cement production, maintenance, and office workers in the cement industry. Mortality from urinary bladder cancer was used as an indirect indicator of the confounding effect of smoking. Results Mortality from all respiratory cancer was significantly increased in cement production workers (PMR?=?1.91; 95% CI 1.54 to 2.33). The proportionate mortality from lung cancer was significantly elevated (PMR?=?2.05; 95% CI 1.65 to 2.52). A statistically significant increase in proportionate mortality due to respiratory (PMR?=?1.7; 95% CI 1.2 to 2.34). and lung cancer (PMR?=?1.67;95% CI?=?1.15-2.34) among maintenance workers has been observed. The PMR among the three groups of workers (production, maintenance, office) did differ significantly for lung cancer (p?=?0.001), while the PMR for urinary bladder cancer found to be similar among the three groups of cement workers. Conclusion Cement production, and maintenance workers presented increased lung and respiratory cancer proportionate mortality, and this finding probably cannot be explained by the confounding effect of smoking alone. Further research including use of prospective cohort studies is needed in order to establish a causal association between occupational exposure to cement and risk of lung cancer. PMID:22738120

  9. Communication Cement-based thermocouples

    E-print Network

    Chung, Deborah D.L.

    Communication Cement-based thermocouples Sihai Wen, D.D.L. Chung* Composite Materials Research Received 31 May 2000; accepted 4 August 2000 Abstract A cement-based thermocouple in the form of a junction between dissimilar cement pastes and exhibiting thermocouple sensitivity 70 7 mV/°C is provided

  10. Cement Mason's Curriculum. Instructional Units.

    ERIC Educational Resources Information Center

    Hendirx, Laborn J.; Patton, Bob

    To assist cement mason instructors in providing comprehensive instruction to their students, this curriculum guide treats both the skills and information necessary for cement masons in commercial and industrial construction. Ten sections are included, as follow: related information, covering orientation, safety, the history of cement, and applying…

  11. Energy Efficiency Improvement and Cost Saving Opportunities for Cement Making. An ENERGY STAR Guide for Energy and Plant Managers

    SciTech Connect

    Galitsky, Christina; Worrell, Ernst; Galitsky, Christina

    2008-01-01

    The cost of energy as part of the total production costs in the cement industry is significant, warranting attention for energy efficiency to improve the bottom line. Historically, energy intensity has declined, although more recently energy intensity seems to have stabilized with the gains. Coal and coke are currently the primary fuels for the sector, supplanting the dominance of natural gas in the 1970s. Most recently, there is a slight increase in the use of waste fuels, including tires. Between 1970 and 1999, primary physical energy intensity for cement production dropped 1 percent/year from 7.3 MBtu/short ton to 5.3 MBtu/short ton. Carbon dioxide intensity due to fuel consumption and raw material calcination dropped 16 percent, from 609 lb. C/ton of cement (0.31 tC/tonne) to 510 lb. C/ton cement (0.26 tC/tonne). Despite the historic progress, there is ample room for energy efficiency improvement. The relatively high share of wet-process plants (25 percent of clinker production in 1999 in the U.S.) suggests the existence of a considerable potential, when compared to other industrialized countries. We examined over 40 energy efficient technologies and measures and estimated energy savings, carbon dioxide savings, investment costs, and operation and maintenance costs for each of the measures. The report describes the measures and experiences of cement plants around the wold with these practices and technologies. Substantial potential for energy efficiency improvement exists in the cement industry and in individual plants. A portion of this potential will be achieved as part of (natural) modernization and expansion of existing facilities, as well as construction of new plants in particular regions. Still, a relatively large potential for improved energy management practices exists.

  12. Low-cost process for hydrogen production

    DOEpatents

    Cha, C.H.; Bauer, H.F.; Grimes, R.W.

    1993-03-30

    A method is provided for producing hydrogen and carbon black from hydrocarbon gases comprising mixing the hydrocarbon gases with a source of carbon and applying radiofrequency energy to the mixture. The hydrocarbon gases and the carbon can both be the products of gasification of coal, particularly the mild gasification of coal. A method is also provided for producing hydrogen and carbon monoxide by treating a mixture of hydrocarbon gases and steam with radio-frequency energy.

  13. Low-cost process for hydrogen production

    DOEpatents

    Cha, Chang Y. (Golden, CO); Bauer, Hans F. (Morgantown, WV); Grimes, Robert W. (Laramie, WY)

    1993-01-01

    A method is provided for producing hydrogen and carbon black from hydrocarbon gases comprising mixing the hydrocarbon gases with a source of carbon and applying radiofrequency energy to the mixture. The hydrocarbon gases and the carbon can both be the products of gasification of coal, particularly the mild gasification of coal. A method is also provided for producing hydrogen an carbon monoxide by treating a mixture of hydrocarbon gases and steam with radio-frequency energy.

  14. From Process to Product: Your Risk Process at Work

    NASA Technical Reports Server (NTRS)

    Kundrot, Craig E.; Fogarty, Jenifer; Charles, John; Buquo, Lynn; Sibonga, Jean; Alexander, David; Horn, Wayne G.; Edwards, J. Michelle

    2010-01-01

    The Space Life Sciences Directorate (SLSD) and Human Research Program (HRP) at the NASA/Johnson Space Center work together to address and manage the human health and performance risks associated with human space flight. This includes all human system requirements before, during, and after space flight, providing for research, and managing the risk of adverse long-term health outcomes for the crew. We previously described the framework and processes developed for identifying and managing these human system risks. The focus of this panel is to demonstrate how the implementation of the framework and associated processes has provided guidance in the management and communication of human system risks. The risks of early onset osteoporosis, CO2 exposure, and intracranial hypertension in particular have all benefitted from the processes developed for human system risk management. Moreover, we are continuing to develop capabilities, particularly in the area of information architecture, which will also be described. We are working to create a system whereby all risks and associated actions can be tracked and related to one another electronically. Such a system will enhance the management and communication capabilities for the human system risks, thereby increasing the benefit to researchers and flight surgeons.

  15. Primary cementing improvement by casing vibration during cement curing time

    SciTech Connect

    Cooke, C.E. Jr.; Gonzalez, O.J.; Broussard, D.J.

    1988-08-01

    Vibration of casing to improve primary cementing was investigated in the laboratory and in a 200-ft (60-m) deep test well. The effect of vibration is to decrease or to eliminate gel strength of the cement slurry as it is curing. The slurry then flows downward to compensate for shrinkage and re-establishes the hydrostatic head of the cement. This method can prevent pore-fluid entry into the annulus before the cement cures and can increase the radial stress at the interface between the formation and the cured cement.

  16. Set retarded cement compositions and methods for well cementing

    SciTech Connect

    Brothers, L.E.; Lindsey, D.W.; Terry, D.T.

    1990-07-17

    This patent describes a method of cementing a zone in a subterranean formation penetrated by a wellbore; It comprises: forming a pumpable set retarded cement slurry comprising hydraulic cement, fresh water, particulate silica having a particle size in the range of from about 0.02 to about 0.5 micron and a set retarder comprising a copolymer consisting essentially of 2-acrylamido, 2-methylpropane sulfonic acid (AMPS) and acrylic acid having an average molecular weight below about 5000 and comprising from about 40 to about 60 mole percent AMPS; pumping the cement slurry into the zone by way of the wellbore, and allowing the cement slurry to set therein.

  17. Neutron powder diffraction studies of Portland cement and cement compounds

    SciTech Connect

    Berliner, R.; Ball, C.; West, P.B.

    1995-12-31

    Neutron powder diffraction data from phase-pure cement compounds has been used to develop structural models suitable for profile refinement of cements. These models were then applied to the determination of cement compound phase abundance in clinkers. This paper reports on the results of clinker phase analysis by powder neutron diffraction and summarizes the results of the refinements of neutron diffraction data from phase-pure cement compounds. The profile refinements provide generally good agreement with cement compound phase abundance measurements of NIST reference clinker specimens by chemical, optical and X-ray methods.

  18. Magnesium-phosphate-glass cements with ceramic-type properties

    DOEpatents

    Sugama, T.; Kukacka, L.E.

    1982-09-23

    Rapid setting magnesium phosphate (Mg glass) cementitious materials consisting of magnesium phosphate cement paste, polyborax and water-saturated aggregate, exhibits rapid setting and high early strength characteristics. The magnesium glass cement is prepared from a cation-leachable powder and a bivalent metallic ion-accepting liquid such as an aqueous solution of diammonium phosphate and ammonium polyphosphate. The cation-leachable powder includes a mixture of two different magnesium oxide powders processed and sized differently which when mixed with the bivalent metallic ion-accepting liquid provides the magnesium glass cement consisting primarily of magnesium ortho phosphate tetrahydrate, with magnesium hydroxide and magnesium ammonium phosphate hexahydrate also present. The polyborax serves as a set-retarder. The resulting magnesium mono- and polyphosphate cements are particularly suitable for use as a cementing matrix in rapid repair systems for deteriorated concrete structures as well as construction materials and surface coatings for fireproof structures.

  19. Magnesium phosphate glass cements with ceramic-type properties

    DOEpatents

    Sugama, Toshifumi (Mastic Beach, NY); Kukacka, Lawrence E. (Port Jefferson, NY)

    1984-03-13

    Rapid setting magnesium phosphate (Mg glass) cementitious materials consisting of magnesium phosphate cement paste, polyborax and water-saturated aggregate exhibiting rapid setting and high early strength characteristics. The magnesium glass cement is prepared from a cation-leachable powder and a bivalent metallic ion-accepting liquid such as an aqueous solution of diammonium phosphate and ammonium polyphosphate. The cation-leachable powder includes a mixture of two different magnesium oxide powders processed and sized differently which when mixed with the bivalent metallic ion-accepting liquid provides the magnesium glass cement consisting primarily of magnesium ortho phosphate tetrahydrate, with magnesium hydroxide and magnesium ammonium phosphate hexahydrate also present. The polyborax serves as a set-retarder. The resulting magnesium mono- and polyphosphate cements are particularly suitable for use as a cementing matrix in rapid repair systems for deteriorated concrete structures as well as construction materials and surface coatings for fireproof structures.

  20. Wet deposition of mercury within the vicinity of a cement plant before and during cement plant maintenance

    NASA Astrophysics Data System (ADS)

    Rothenberg, Sarah E.; McKee, Lester; Gilbreath, Alicia; Yee, Donald; Connor, Mike; Fu, Xuewu

    2010-03-01

    Hg species (total mercury, methylmercury, reactive mercury) in precipitation were investigated in the vicinity of the Lehigh Hanson Permanente Cement Plant in the San Francisco Bay Area, CA., USA. Precipitation was collected weekly between November 29, 2007 and March 20, 2008, which included the period in February and March 2008 when cement production was minimized during annual plant maintenance. When the cement plant was operational, the volume weighted mean (VWM) and wet depositional flux for total Hg (Hg T) were 6.7 and 5.8 times higher, respectively, compared to a control site located 3.5 km east of the cement plant. In February and March, when cement plant operations were minimized, levels were approximately equal at both sites (the ratio for both parameters was 1.1). Due to the close proximity between the two sites, meteorological conditions (e.g., precipitation levels, wind direction) were similar, and therefore higher VWM Hg T levels and Hg T deposition likely reflected increased Hg emissions from the cement plant. Methylmercury (MeHg) and reactive Hg (Hg(II)) were also measured; compared to the control site, the VWM for MeHg was lower at the cement plant (the ratio = 0.75) and the VWM for Hg(II) was slightly higher (ratio = 1.2), which indicated the cement plant was not likely a significant source of these Hg species to the watershed.

  1. Contact damage failure analyses of fretting wear behavior of the metal stem titanium alloy-bone cement interface.

    PubMed

    Zhang, Lanfeng; Ge, Shirong; Liu, Hongtao; Wang, Qingliang; Wang, Liping; Xian, Cory J

    2015-11-01

    Although cemented titanium alloy is not favored currently in the Western world for its poor clinical and radiography outcomes, its lower modulus of elasticity and good biocompatibility are instrumental for its ability supporting and transforming physical load, and it is more suitable for usage in Chinese and Japanese populations due to their lower body weights and unique femoral characteristics. Through various friction tests of different cycles, loads and conditions and by examining fretting hysteresis loops, fatigue process curves and wear surfaces, the current study investigated fretting wear characteristics and wear mechanism of titanium alloy stem-bone cement interface. It was found that the combination of loads and displacement affected the wear quantity. Friction coefficient, which was in an inverse relationship to load under the same amplitude, was proportional to amplitudes under the same load. Additionally, calf serum was found to both lubricate and erode the wear interface. Moreover, cement fatigue contact areas appeared black/oxidative in dry and gruel in 25% calf serum. Fatigue scratches were detected within contact areas, and wear scars were found on cement and titanium surfaces, which were concave-shaped and ring concave/ convex-shaped, respectively. The coupling of thermoplastic effect and minimal torque damage has been proposed to be the major reason of contact damage. These data will be important for further studies analyzing metal-cement interface failure performance and solving interface friction and wear debris production issues. PMID:26241891

  2. Process for the production of hydrogen peroxide

    DOEpatents

    Datta, R.; Randhava, S.S.; Tsai, S.P.

    1997-09-02

    An integrated membrane-based process method for producing hydrogen peroxide is provided comprising oxidizing hydrogenated anthraquinones with air bubbles which were created with a porous membrane, and then contacting the oxidized solution with a hydrophilic membrane to produce an organics free, H{sub 2}O{sub 2} laden permeate. 1 fig.

  3. Process for the production of hydrogen peroxide

    DOEpatents

    Datta, Rathin (Chicago, IL); Randhava, Sarabjit S. (Evanston, IL); Tsai, Shih-Perng (Naperville, IL)

    1997-01-01

    An integrated membrane-based process method for producing hydrogen peroxide is provided comprising oxidizing hydrogenated anthraquinones with air bubbles which were created with a porous membrane, and then contacting the oxidized solution with a hydrophilic membrane to produce an organics free, H.sub.2 O.sub.2 laden permeate.

  4. Process for the production of liquid hydrocarbons

    DOEpatents

    Bhatt, Bharat Lajjaram; Engel, Dirk Coenraad; Heydorn, Edward Clyde; Senden, Matthijis Maria Gerardus

    2006-06-27

    The present invention concerns a process for the preparation of liquid hydrocarbons which process comprises contacting synthesis gas with a slurry of solid catalyst particles and a liquid in a reactor vessel by introducing the synthesis gas at a low level into the slurry at conditions suitable for conversion of the synthesis gas into liquid hydrocarbons, the solid catalyst particles comprising a catalytic active metal selected from cobalt or iron on a porous refractory oxide carrier, preferably selected from silica, alumina, titania, zirconia or mixtures thereof, the catalyst being present in an amount between 10 and 40 vol. percent based on total slurry volume liquids and solids, and separating liquid material from the solid catalyst particles by using a filtration system comprising an asymmetric filtration medium (the selective side at the slurry side), in which filtration system the average pressure differential over the filtration medium is at least 0.1 bar, in which process the particle size distribution is such that at least a certain amount of the catalyst particles is smaller than the average pore size of the selective layer of the filtration medium. The invention also comprises an apparatus to carry out the process described above.

  5. Sweet sorghum processing for alcohol production

    SciTech Connect

    Schmulevich, I.; Coble, C.G.; Egg, R.P.

    1983-12-01

    Several processing techniques for producing ethanol from sweet sorghum were investigated. Fermentating chopped stalks yielded more ethanol than shredded sorghum or juice. Leaf removal prior to fermentation resulted in higher yields per unit feedstock. Removal of solids after fermentation yielded slightly more ethanol than solids removal before fermentation.

  6. Content, Process, and Product: Modeling Differentiated Instruction

    ERIC Educational Resources Information Center

    Taylor, Barbara Kline

    2015-01-01

    Modeling differentiated instruction is one way to demonstrate how educators can incorporate instructional strategies to address students' needs, interests, and learning styles. This article discusses how secondary teacher candidates learn to focus on content--the "what" of instruction; process--the "how" of instruction;…

  7. Separation processes during binary monotectic alloy production

    NASA Technical Reports Server (NTRS)

    Frazier, D. O.; Facemire, B. R.; Kaukler, W. F.; Witherow, W. K.; Fanning, U.

    1984-01-01

    Observation of microgravity solidification processes indicates that outside of sedimentation, at least two other important effects can separate the phases: critical-point wetting and spreading; and thermal migration of second-phase droplets due to interfacial tension gradients. It is difficult to study these surface tension effects while in a unit gravity field. In order to investigate the processes occurring over a temperature range, i.e., between a consolute point and the monotectic temperature, it is necessary to use a low-gravity environment. The MSFC drop tube (and tower), the ballistic trajectory KC-135 airplane, and the Space Shuttle are ideal facilities to aid formation and testing of hypotheses. Much of the early work in this area focuses on transparent materials so that process dynamics may be studied by optical techniques such as photography for viewing macro-processes; holography for studying diffusional growth; spinodal decomposition and coalescence; ellipsometry for surface wetting and spreading effects; and interferometry and spectroscopy for small-scale spatial resolution of concentration profiles.

  8. Study on Product Innovative Design Process Driven by Ideal Solution

    NASA Astrophysics Data System (ADS)

    Zhang, Fuying; Lu, Ximei; Wang, Ping; Liu, Hui

    Product innovative design in companies today relies heavily on individual members’ experience and creative ideation as well as their skills of integrating creativity and innovation tools with design methods agilely. Creative ideation and inventive ideas generation are two crucial stages in product innovative design process. Ideal solution is the desire final ideas for given problem, and the striving reaching target for product design. In this paper, a product innovative design process driven by ideal solution is proposed. This design process encourages designers to overcome their psychological inertia, to foster creativity in a systematic way for acquiring breakthrough creative and innovative solutions in a reducing sphere of solution-seeking, and results in effective product innovative design rapidly. A case study example is also presented to illustrate the effectiveness of the proposed design process.

  9. Nanofiber adsorbents for high productivity downstream processing.

    PubMed

    Hardick, Oliver; Dods, Stewart; Stevens, Bob; Bracewell, Daniel G

    2013-04-01

    Electrospun polymeric nanofiber adsorbents offer an alternative ligand support surface for bioseparations. Their non-woven fiber structure with diameters in the sub-micron range creates a remarkably high surface area. To improve the purification productivity of biological molecules by chromatography, cellulose nanofiber adsorbents were fabricated and assembled into a cartridge and filter holder format with a volume of 0.15 mL, a bed height of 0.3 mm and diameter of 25 mm. The present study investigated the performance of diethylaminoethyl (DEAE) derivatized regenerated cellulose nanofiber adsorbents based on criteria including mass transfer and flow properties, binding capacity, and fouling effects. Our results show that nanofibers offer higher flow and mass transfer properties. The non-optimized DEAE-nanofiber adsorbents indicate a binding capacity of 10% that of packed bed systems with BSA as a single component system. However, they operate reproducibly at flowrates of a hundred times that of packed beds, resulting in a potential productivity increase of 10-fold. Lifetime studies showed that this novel adsorbent material operated reproducibly with complex feed material (centrifuged and 0.45 µm filtered yeast homogenate) and harsh cleaning-in-place conditions over multiple cycles. DEAE nanofibers showed superior operating performance in permeability and fouling over conventional adsorbents indicating their potential for bioseparation applications. PMID:23097054

  10. Cements with low Clinker Content

    NASA Astrophysics Data System (ADS)

    García-Lodeiro, I.; Fernández-Jiménez, A.; Palomo, A.

    2015-11-01

    Hybrid alkaline cements are multi-component systems containing a high percentage of mineral additions (fly ash, blast furnace slag), low proportions (<30%) of Portland clinker and scarce amounts of alkaline activators. The substantially lower amount of clinker needed to manufacture these binders in comparison to ordinary Portland cement is both economically and ecologically beneficial. Their enormous versatility in terms of the raw materials used has made them the object of considerable interest. The present study explored the mechanical strength of binary blends mixes; B1= 20% clinker (CK) + 80% fly ash (FA) and B2=20% clinker + 80% blast furnace slag (BFS), both hydrated in the presence and absence of an alkaline activator specifically designed for this purpose. The use of the activator enhanced the development of early age strength considerably. All the hydrated matrices were characterised with XRD, SEM/EDX and (29Si and 27Al) NMR. The use of the alkaline activator generated reaction products consisting primarily of a mix of gels ((N,C)-A-S-H and C-A-S-H) whose respective proportions were found to depend upon system composition and initial reactivity.

  11. Method of reducing fluid loss in cement compositions

    SciTech Connect

    Brothers, L.E.

    1989-02-21

    A method is described for cementing a conduit in a borehole penetrating an earthen formation by introducing a cementing composition into the space between the conduit and the formation, the cementing composition comprising: hydraulic content, an aqueous fluid, and a fluid-loss additive consisting essentially of a polymer reaction product of styrene with 2-acrylamido-2-methylpropanesulfonic acid and their salts, the styrene being present in the polymer in an amount of from about 15 to about 60 mole percent of the polymer.

  12. Process for production desulfurized of synthesis gas

    DOEpatents

    Wolfenbarger, James K. (Torrance, CA); Najjar, Mitri S. (Wappingers Falls, NY)

    1993-01-01

    A process for the partial oxidation of a sulfur- and silicate-containing carbonaceous fuel to produce a synthesis gas with reduced sulfur content which comprises partially oxidizing said fuel at a temperature in the range of 1900.degree.-2600.degree. F. in the presence of a temperature moderator, an oxygen-containing gas and a sulfur capture additive which comprises a calcium-containing compound portion, a sodium-containing compound portion, and a fluoride-containing compound portion to produce a synthesis gas comprising H.sub.2 and CO with a reduced sulfur content and a molten slag which comprises (1) a sulfur-containing sodium-calcium-fluoride silicate phase; and (2) a sodium-calcium sulfide phase.

  13. Entropy production in oscillatory processes during photosynthesis.

    PubMed

    López-Agudelo, Víctor A; Barragán, Daniel

    2014-01-01

    The flow of matter and heat and the rate of enzymatic reactions are examined using two models of photosynthesis that exhibit sustained and damped oscillatory dynamics, with the objective of calculating the rate of entropy generation and studying the effects of temperature and kinetic constants on the thermodynamic efficiency of photosynthesis. The global coefficient of heat transfer and the direct and inverse constants of the formation reaction of the RuBisCO-CO2 complex were used as control parameters. Results show that when the system moves from isothermal to non-isothermal conditions, the transition from a steady state to oscillations facilitates an increase in the energy efficiency of the process. The simulations were carried out for two photosynthetic models in a system on a chloroplast reactor scale. PMID:24162177

  14. MCFC integrated system in a biodiesel production process

    NASA Astrophysics Data System (ADS)

    Urbani, F.; Freni, S.; Galvagno, A.; Chiodo, V.

    2011-03-01

    The continuous increasing in biodiesel production by transesterification process is leading to an excess of glycerol production as a byproduct. The utilization of this huge amount of glycerol appears as a not easy solvable problem and thus several authors have proposed alternative ways. The integration of the main production process with a glycerol feed molten carbonate fuel cells bottoming cycle, to satisfy plant energy requirements, seems to be one of the most promising one. The proposed paper reports the main results obtained by authors in the framework of an investigation on a possible use of glycerol as energy sources for a real pilot plant for biodiesel production. An overall evaluation of worldwide biodiesel production plants was made and especially about the production capacity in European Union in the last decade. To make a more detailed study, authors were taken into account a real production plant. After a preliminary step, purported to plant mass and energy flows determination, authors considered the integration of a bottoming cycle based on: (i) steam reforming of glycerol for syn-gas production; (ii) molten carbonate fuel cells (MCFC) system supplied by syn-gas for heat and electricity production. A mathematical model, based on experimental data, has been developed to calculate mass and energy balances for the proposed plant lay-out as well as plant energy efficiency enhancement has been determined. Results have evidenced the feasibility of this process and demonstrated that plant integrated with bottoming cycle can reach a very high level of energy self-production.

  15. Assessment of Energy Efficiency Improvement and CO2 Emission Reduction Potentials in the Cement Industry in China

    SciTech Connect

    Hasanbeigi, Ali; Morrow, William; Masanet, Eric; Sathaye, Jayant; Xu, Tengfang

    2012-06-15

    China’s annual cement production (i.e., 1,868 Mt) in 2010 accounted for nearly half of the world’s annual cement production in the same year. We identified and analyzed 23 energy efficiency technologies and measures applicable to the processes in the cement industry. The Conservation Supply Curve (CSC) used in this study is an analytical tool that captures both the engineering and the economic perspectives of energy conservation. Using a bottom-up electricity CSC model, the cumulative cost-effective electricity savings potential for the Chinese cement industry for 2010-2030 is estimated to be 251 TWh, and the total technical electricity saving potential is 279 TWh. The CO2 emissions reduction associated with cost-effective electricity savings is 144 Mt CO2 and the CO2 emission reduction associated with technical electricity saving potential is 161 Mt CO2. The fuel CSC model for the cement industry suggests cumulative cost-effective fuel savings potential of 4,326 PJ which is equivalent to the total technical potential with associated CO2 emission reductions of 406 Mt CO2. In addition, a sensitivity analysis with respect to the discount rate used is conducted to assess the effect of changes in this parameter on the results. We also developed a scenario in which instead of only implementing the international technologies in 2010-2030, we implement both international and Chinese domestic technologies during the analysis period and calculate the saving and cost of conserved energy accordingly. The result of this study gives a comprehensive and easy to understand perspective to the Chinese cement industry and policy makers about the energy efficiency potential and its associated cost.

  16. Kinetics of cobalt cementation on zinc powder

    SciTech Connect

    Polcaro, A.M.; Palmas, S.; Dernini, S.

    1995-09-01

    The cementation process may be considered an interesting method to treat dilute solutions containing metal ions. The aim of the process may be either the removal of pollutant metals or the recovery of economically valuable metals such as Ag from spent photographic liquors. The kinetics of cobalt cementation on Zn powder from zinc sulfate concentrated solutions in the presence of copper and antimony ions was investigated in stirred tank reactors. The composition of the solutions was in the range usually utilized in industrial zinc electrowinning plants. The results showed that the reaction occurs by means of the formation of crystallization nuclei of noble metals on the zinc powder, followed by the cementation of cobalt ions on these newly-formed nuclei. Mass transfer to the reaction surface is shown to be the controlling step in copper and antimony reduction, and an equation correlating mass transfer coefficients has been determined. A kinetic equation, which interprets the influence of stirring speed and solution composition on cobalt cementation, has also been proposed.

  17. New cement formulation helps solve deep cementing problems

    SciTech Connect

    Brothers, L.E.; DeBlanc, F.X.

    1989-06-01

    Invert-emulsion muds are used in most deep, hot wells. The internal aqueous phase of these muds frequently contains high concentrations of salts. It is desirable to complete these wells with a cement slurry containing salt concentrations up to and including saturation to minimize compatibility problems between cement slurry and mud. Above their effective temperature range, however, saturated salt cements - though still considered desirable for their other properties - pose design difficulties regarding thickening time, fluid loss, and rheology. High salt concentrations tend to decrease the effectiveness of most common cement additives - e.g., retarders, fluid-loss additives, and dispersants. At high temperatures, concentrations of these additives can become unacceptably large, while the additives themselves are not as effective under these conditions. Development of and field experience with a new cementing formulation for deep, high-temperature, saturated-salt applications have helped resolve the cement design problems encountered in south Texas and southern and offshore Louisiana. A single synthetic-polymer additive provides cement retardation, fluid-loss control, and dispersant properties with normal design considerations as opposed to the lengthy design requirements of other cement systems. A particular benefit derived from use of the new cement system involves cementing of long liners. Such liners frequently require squeeze cementing at the liner top because the cement is designed for conditions at the bottom of the liner and is thus frequently over-retarded for the cooler temperatures encountered at the top of the liner. This over-retardation tendency is alleviated greatly by use of the new saturated-salt cement additive.

  18. 7 CFR 926.11 - Processed cranberries or cranberry products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Processed cranberries or cranberry products. 926.11 Section 926.11 Agriculture...REPORTING AND RECORDKEEPING REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER...

  19. 7 CFR 926.11 - Processed cranberries or cranberry products.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Processed cranberries or cranberry products. 926.11 Section 926.11 Agriculture...REPORTING AND RECORDKEEPING REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER...

  20. 7 CFR 926.11 - Processed cranberries or cranberry products.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Processed cranberries or cranberry products. 926.11 Section 926.11 Agriculture...REPORTING AND RECORDKEEPING REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER...

  1. 7 CFR 926.11 - Processed cranberries or cranberry products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Processed cranberries or cranberry products. 926.11 Section 926.11 Agriculture...REPORTING AND RECORDKEEPING REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER...

  2. 7 CFR 926.11 - Processed cranberries or cranberry products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Processed cranberries or cranberry products. 926.11 Section 926.11 Agriculture...REPORTING AND RECORDKEEPING REQUIREMENTS APPLICABLE TO CRANBERRIES NOT SUBJECT TO THE CRANBERRY MARKETING ORDER...

  3. Recombinant protein production and insect cell culture and process

    NASA Technical Reports Server (NTRS)

    Spaulding, Glenn (inventor); Prewett, Tacey (inventor); Goodwin, Thomas (inventor); Francis, Karen (inventor); Andrews, Angela (inventor); Oconnor, Kim (inventor)

    1993-01-01

    A process has been developed for recombinant production of selected polypeptides using transformed insect cells cultured in a horizontally rotating culture vessel modulated to create low shear conditions. A metabolically transformed insect cell line is produced using the culture procedure regardless of genetic transformation. The recombinant polypeptide can be produced by an alternative process using the cultured insect cells as host for a virus encoding the described polypeptide such as baculovirus. The insect cells can also be a host for viral production.

  4. Exclusive processes of charmonium production and charmonium wave functions

    SciTech Connect

    Braguta, V. V. Likhoded, A. K. Luchinsky, A. V.

    2012-01-15

    Results obtained by studying the properties of the leading-twist wave functions for the S- and P-wave states of charmonia are presented. Wave-function models that can be used to calculate various processes involving the production of these mesons were constructed on the basis of these investigations. Calculations for some exclusive processes of charmonium production were performed within the models in question.

  5. Recombinant Protein Production and Insect Cell Culture and Process

    NASA Technical Reports Server (NTRS)

    Spaulding, Glenn F. (Inventor); Goodwin, Thomas J. (Inventor); OConnor, Kim C. (Inventor); Francis, Karen M. (Inventor); Andrews, Angela D. (Inventor); Prewett, Tracey L. (Inventor)

    1997-01-01

    A process has been developed for recombinant production of selected polypeptides using transformed insect cells cultured in a horizontally rotating culture vessel modulated to create low shear conditions. A metabolically transformed insect cell line is produced using the culture procedure regardless of genetic transformation. The recombinant polypeptide can be produced by an alternative process using virtually infected or stably transformed insect cells containing a gene encoding the described polypeptide. The insect cells can also be a host for viral production.

  6. Barnacle cement: a polymerization model based on evolutionary concepts

    PubMed Central

    Dickinson, Gary H.; Vega, Irving E.; Wahl, Kathryn J.; Orihuela, Beatriz; Beyley, Veronica; Rodriguez, Eva N.; Everett, Richard K.; Bonaventura, Joseph; Rittschof, Daniel

    2009-01-01

    Summary Enzymes and biochemical mechanisms essential to survival are under extreme selective pressure and are highly conserved through evolutionary time. We applied this evolutionary concept to barnacle cement polymerization, a process critical to barnacle fitness that involves aggregation and cross-linking of proteins. The biochemical mechanisms of cement polymerization remain largely unknown. We hypothesized that this process is biochemically similar to blood clotting, a critical physiological response that is also based on aggregation and cross-linking of proteins. Like key elements of vertebrate and invertebrate blood clotting, barnacle cement polymerization was shown to involve proteolytic activation of enzymes and structural precursors, transglutaminase cross-linking and assembly of fibrous proteins. Proteolytic activation of structural proteins maximizes the potential for bonding interactions with other proteins and with the surface. Transglutaminase cross-linking reinforces cement integrity. Remarkably, epitopes and sequences homologous to bovine trypsin and human transglutaminase were identified in barnacle cement with tandem mass spectrometry and/or western blotting. Akin to blood clotting, the peptides generated during proteolytic activation functioned as signal molecules, linking a molecular level event (protein aggregation) to a behavioral response (barnacle larval settlement). Our results draw attention to a highly conserved protein polymerization mechanism and shed light on a long-standing biochemical puzzle. We suggest that barnacle cement polymerization is a specialized form of wound healing. The polymerization mechanism common between barnacle cement and blood may be a theme for many marine animal glues. PMID:19837892

  7. Standardization of Components, Products and Processes with Data Mining

    E-print Network

    Kusiak, Andrew

    1 Standardization of Components, Products and Processes with Data Mining Bruno AGARD Département de - 1527, USA andrew-kusiak@uiowa.edu ABSTRACT Data mining offers tools for extracting knowledge from databases. This paper discusses applications of data mining in standardization of components, products

  8. PROCESSING OF FATS AND OILS INTO VALUE-ADDED PRODUCTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The modification of fats and oils and their co-products for added value is a major theme of lipid research. Biotechnological processes often are favored for their mild reaction conditions and low environmental impact; they sometimes are the only practical routes to desired products. Nevertheless, ...

  9. Assessing Process and Product with Young Children in School Settings.

    ERIC Educational Resources Information Center

    Stern, Carolyn

    What needs to be done with preschool programs is to define specifically their desired product (the behaviors we want in the children) and to determine the optimal process by which this product can be brought about. Using an instrument called the Observation of Substantive Curricular Input in 1967-68, a coding system based on a series of 3-minute…

  10. Natural fiber production, harvesting, and preliminary processing: options and opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The utilization of natural fibers and plant oils in bio-products introduces numerous logistical challenges not typically encountered with non-agricultural resources. Once it has been determined that a plant material is suitable for commercial development, the production, harvesting, and processing s...

  11. 40 CFR 161.162 - Description of production process.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Description of production process. 161.162 Section 161.162 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Product Chemistry Data...

  12. 40 CFR 161.162 - Description of production process.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Description of production process. 161.162 Section 161.162 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Product Chemistry Data...

  13. 40 CFR 161.162 - Description of production process.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Description of production process. 161.162 Section 161.162 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Product Chemistry Data...

  14. Vehicle and Heavy Equipment Integrated Product & Process Development (IPPD)

    E-print Network

    Beckermann, Christoph

    Vehicle and Heavy Equipment Integrated Product & Process Development (IPPD) Technology Development City, IA 52242 Beckermann, C., and Fischer, G.W., "Vehicle and Heavy Equipment Integrated Product, 1993. #12;Abstract An overview is presented of the recently proposed Vehicle and Heavy Equipment

  15. NIR spectroscopy for determining soy contents in processed meat products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soy products such as soy concentrate, soy protein and soy grits are used as a meat extender in processed meat products to improve meat texture. However, soy allergies are one of the common food allergies, especially in infants and young children, and can be mild to life-threatening. The United State...

  16. 76 FR 13973 - United States Warehouse Act; Processed Agricultural Products Licensing Agreement

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-15

    ...of a processed agricultural product is apple juice concentrate. In the past, USDA...processed agricultural products such as apple juice concentrate and other similar products...processed agricultural products such as apple juice concentrate? What types of...

  17. Reuse of cement-solidified municipal incinerator fly ash in cement mortars: physico-mechanical and leaching characteristics.

    PubMed

    Cinquepalmi, Maria Anna; Mangialardi, Teresa; Panei, Liliana; Paolini, Antonio Evangelista; Piga, Luigi

    2008-03-01

    The reuse of cement-solidified Municipal Solid Waste Incinerator (MSWI) fly ash (solidified/stabilised (S/S) product) as an artificial aggregate in Portland cement mortars was investigated. The S/S product consisted of a mixture of 48 wt.% washed MSWI fly ash, 20 wt.% Portland cement and 32 wt.% water, aged for 365 days at 20 degrees C and 100% RH. Cement mortars (water/cement weight ratio=0.62) were made with Portland cement, S/S product and natural sand at three replacement levels of sand with S/S product (0%, 10% and 50% by mass). After 28 days of curing at 20 degrees C and 100% RH, the mortar specimens were characterised for their physico-mechanical (porosity, compressive strength) and leaching behaviour. No retardation in strength development, relatively high compressive strengths (up to 36 N/mm2) and low leaching rates of heavy metals (Cr, Cu, Pb and Zn) were always recorded. The leaching data from sequential leach tests on monolithic specimens were successfully elaborated with a pseudo-diffusional model including a chemical retardation factor related to the partial dissolution of contaminant. PMID:17658684

  18. Processing, quality and safety of irradiation - and high pressure processed meat and seafood products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the past two decades, worldwide demands for meat and seafood products have increased dramatically due to the improved economical condition in many countries. To meet the demand, the producers have increased the production of meat and seafood products as well as applied new processing techniques t...

  19. Mineral resource of the month: hydraulic cement

    USGS Publications Warehouse

    van Oss, Hendrik G.

    2012-01-01

    Hydraulic cements are the binders in concrete and most mortars and stuccos. Concrete, particularly the reinforced variety, is the most versatile of all construction materials, and most of the hydraulic cement produced worldwide is portland cement or similar cements that have portland cement as a basis, such as blended cements and masonry cements. Cement typically makes up less than 15 percent of the concrete mix; most of the rest is aggregates. Not counting the weight of reinforcing media, 1 ton of cement will typically yield about 8 tons of concrete.

  20. A Knowledge-based Product Derivation Process and some Ideas how to Integrate Product Development

    E-print Network

    Hamburg,.Universität

    in the proposed knowledge-based derivation process. I. INTRODUCTION The product line approach makes the distinction between a domain engineering part, where a common platform for an arbitrary number of products is designed and realized, and an application specific engineering part, where a customer product is derived

  1. Study of laser molten welding of cemented carbides and steel

    SciTech Connect

    Tian Nailiang; Yang Yongqiang

    1996-12-31

    The laser molten welding of cemented carbides and steel is discussed in this paper. It presents the mechanism of dip soldering. The changes of material structure of welding seam, elements composition and the cause of fissures have been analyzed. The changes of tension of carbides and cobaltic phase in welding process are investigated. The effect of laser plasma on surface of specimen is discussed. The welding results of heterogeneous materials between L135 cemented carbides and 6542{number_sign} tool steel, YG15, YG12, YG8 cemented carbides and 45{number_sign} steel are also discussed.

  2. Product and process effectiveness using performance-based auditing techniques

    SciTech Connect

    Horseman, M.L.

    1995-12-01

    Focus is the backbone of genius. Focus is the lifeblood of adequate products and effective processes. Focus is the theme of Performance-Based Audits (PBA). The Civilian Radioactive Waste Management (CRWM) Program is using the PBA tool extensively to focus on the evaluation of product adequacy and process effectiveness. The term Performance-Based Audit has been around for several years. however, the approach presented here for the systematic end-product selection, planning, and measurement of adequacy and effectiveness is new and innovative.

  3. Top-quark processes at NLO in production and decay

    SciTech Connect

    Campbell, John M.; Ellis, R.Keith

    2012-04-01

    We describe the implementation of top production and decay processes in the parton-level Monte Carlo program MCFM. By treating the top quark as being on-shell, we can factorize the amplitudes for top-pair production, s-channel single-top production, and t-channel single-top production into the product of an amplitude for production and an amplitude for decay. In this way we can retain all spin correlations. Both the production and the decay amplitudes are calculated consistently at next-to-leading order in alpha_s. The full dependence on the b-quark mass is also kept. Phenomenological results are presented for various kinematic distributions at the LHC and for the top quark forward-backward asymmetry at the Tevatron.

  4. 40 CFR 161.162 - Description of production process.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... applicant must submit information on the production (reaction) processes used to produce the active... continuous (a single reaction process from starting materials to active ingredient), but is accomplished in...) A flow chart of the chemical equations of each intended reaction occurring at each step of...

  5. Image processing system performance prediction and product quality evaluation

    NASA Technical Reports Server (NTRS)

    Stein, E. K.; Hammill, H. B. (principal investigators)

    1976-01-01

    The author has identified the following significant results. A new technique for image processing system performance prediction and product quality evaluation was developed. It was entirely objective, quantitative, and general, and should prove useful in system design and quality control. The technique and its application to determination of quality control procedures for the Earth Resources Technology Satellite NASA Data Processing Facility are described.

  6. COBY PRODUCTS AND A PROCESS FOR THEIR MANUFACTURE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A novel method for the treatment of cotton byproducts to yield value-added products while reducing the wear on processing equipment is described. In this process, cotton byproducts, or waste, are ground and compacted and treated with a gellable polysaccharide. The polysaccharide is gelatinized, eith...

  7. Low energy production processes in manufacturing of silicon solar cells

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A. R.

    1976-01-01

    Ion implantation and pulsed energy techniques are being combined for fabrication of silicon solar cells totally under vacuum and at room temperature. Simplified sequences allow very short processing times with small process energy consumption. Economic projections for fully automated production are excellent.

  8. Self-tuning process monitoring system for process-based product

    SciTech Connect

    Hillaire, R.; Loucks, C.

    1998-02-01

    The hidden qualities of a product are often revealed in the process. Subsurface material damage, surface cracks, and unusual burr formation can occur during a poorly controlled machining process. Standard post process inspection is costly and may not reveal these conditions. However, by monitoring the proper process parameters, these conditions are readily detectable without incurring the cost of post process inspection. In addition, many unforeseen process anomalies may be detected using an advanced process monitoring system. This work created a process monitoring system for milling machines which mapped the forces, power, vibration, and acoustic emissions generated during a cutting cycle onto a 3D model of the part being machined. The hyperpoint overlay can be analyzed and visualized with VRML (Virtual Reality Modeling Language). Once the Process Monitoring System is deployed, detailed inspection may be significantly reduced or eliminated. The project deployed a Pro-Engineer to VRML model conversion routine, advanced visualization interface, tool path transformation with mesh generation routine, hyperpoint overlay routine, stable sensor array, sensor calibration routine, and machine calibration methodology. The technology created in this project can help validate production of WR (War Reserve) components by generating process signatures for products, processes, and lot runs. The signatures of each product can be compared across all products made within and across lot runs to determine if the processes that produced the product are consistently providing superior quality. Furthermore, the qualities of the processes are visibly apparent, since the part model is overlaid with process data. The system was evaluated on three different part productions.

  9. Ionic liquid-based green processes for energy production.

    PubMed

    Zhang, Suojiang; Sun, Jian; Zhang, Xiaochun; Xin, Jiayu; Miao, Qingqing; Wang, Jianji

    2014-11-21

    To mitigate the growing pressure on resource depletion and environment degradation, the development of green processes for the production of renewable energy is highly required. As a class of novel and promising media, ionic liquids (ILs) have shown infusive potential applications in energy production. Aiming to offer a critical overview regarding the new challenges and opportunities of ILs for developing green processes of renewable energy, this article emphasises the role of ILs as catalysts, solvents, or electrolytes in three broadly interesting energy production processes from renewable resources, such as CO2 conversion to fuels and fuel additives, biomass pretreatment and conversion to biofuels, as well as solar energy and energy storage. It is expected that this article will stimulate a generation of new ideas and new technologies in IL-based renewable energy production. PMID:24553494

  10. Fish Processed Production Planning Using Integer Stochastic Programming Model

    NASA Astrophysics Data System (ADS)

    Firmansyah, Mawengkang, Herman

    2011-06-01

    Fish and its processed products are the most affordable source of animal protein in the diet of most people in Indonesia. The goal in production planning is to meet customer demand over a fixed time horizon divided into planning periods by optimizing the trade-off between economic objectives such as production cost and customer satisfaction level. The major decisions are production and inventory levels for each product and the number of workforce in each planning period. In this paper we consider the management of small scale traditional business at North Sumatera Province which performs processing fish into several local seafood products. The inherent uncertainty of data (e.g. demand, fish availability), together with the sequential evolution of data over time leads the production planning problem to a nonlinear mixed-integer stochastic programming model. We use scenario generation based approach and feasible neighborhood search for solving the model. The results which show the amount of each fish processed product and the number of workforce needed in each horizon planning are presented.

  11. Virtual Collaborative Simulation Environment for Integrated Product and Process Development

    NASA Technical Reports Server (NTRS)

    Gulli, Michael A.

    1997-01-01

    Deneb Robotics is a leader in the development of commercially available, leading edge three- dimensional simulation software tools for virtual prototyping,, simulation-based design, manufacturing process simulation, and factory floor simulation and training applications. Deneb has developed and commercially released a preliminary Virtual Collaborative Engineering (VCE) capability for Integrated Product and Process Development (IPPD). This capability allows distributed, real-time visualization and evaluation of design concepts, manufacturing processes, and total factory and enterprises in one seamless simulation environment.

  12. A unique experience with foamed cement

    SciTech Connect

    Piot, B.; Ferriere, R.; Fraboulet, B.

    1994-12-31

    An extensive laboratory program showed that foamed cement was the only technically feasible solution to prepare a floating cement plug for solving severe lost circulation problems in big caverns. The technique had, however, to be adapted to fit well conditions that are relatively unusual in the oil field: the cement slurry should not become diluted and destabilized upon exiting the drill pipe and entering the 60-plus inches wellbore and the huge caves, several feet in radius, both filled with sea water. Moreover, the foam had to remain stable, even when surrounded by large volume of water, until cement setting. Therefore a technique of using protective fluids was devised. In addition, logistics dictated the use of compressed air rather than nitrogen to prepare the foamed slurry. Therefore special gas metering and regulation devices were used for the first time in the oil field in order to automate the process and get a perfect control of the slurry density whatever the slurry mixing and pumping rates. Before field implementation, the metering and regulation device was successfully yard tested, the gas phase being supplied by nitrogen bottles. The successful field implementation with air compressors, together with the protective fluid technique to combat lost circulation in loose coral reef and in highly fractured dolomitic formation, is described.

  13. Vibrational investigation of calcium-silicate cements for endodontics in simulated body fluids

    NASA Astrophysics Data System (ADS)

    Taddei, Paola; Modena, Enrico; Tinti, Anna; Siboni, Francesco; Prati, Carlo; Gandolfi, Maria Giovanna

    2011-05-01

    Calcium-silicate MTA (Mineral Trioxide Aggregate) cements have been recently developed for oral and endodontic surgery. This study was aimed at investigating commercial (White ProRoot MTA, White and Grey MTA-Angelus) and experimental (wTC-Bi) accelerated calcium-silicate cements with regards to composition, hydration products and bioactivity upon incubation for 1-28 days at 37 °C, in Dulbecco's Phosphate Buffered Saline (DPBS). Deposits on the surface of the cements and the composition changes during incubation were investigated by micro-Raman and ATR/FT-IR spectroscopy, and pH measurements. Vibrational techniques disclosed significant differences in composition among the unhydrated cements, which significantly affected the bioactivity as well as pH, and hydration products of the cements. After one day in DPBS, all the cements were covered by a more or less homogeneous layer of B-type carbonated apatite. The experimental cement maintained a high bioactivity, only slightly lower than the other cements and appears a valid alternative to commercial cements, in view of its adequate setting time properties. The bioactivity represents an essential property to favour bone healing and makes the calcium-silicate cements the gold standard materials for root-apical endodontic surgery.

  14. Salmonellae Associated with Further-processed Turkey Products1

    PubMed Central

    Bryan, Frank L.; Ayres, John C.; Kraft, Allen A.

    1968-01-01

    “Further-processed” turkey products, prepared from chilled, eviscerated, and thawed carcasses at two commercial turkey-processing plants, were evaluated, for the presence of salmonellae. These organisms were isolated from swab samples from 12% of chilled, eviscerated turkey carcasses, 27% of finished products, and 24% of processing equipment. The same serotypes as those found throughout a plant on any one visit were recovered from 31% of rinse-samples taken from hands and gloves of processing personnel. Salmonellae were found in samples taken on 37 of 48 visits; a greater number of recoveries were made on days when freshly killed turkeys were processed (87%) than when frozen-defrosted carcasses were processed (59%). The predominant serotype isolated from meat and environment usually changed from visit to visit. Salmonella sandiego and Salmonella anatum were the most frequent among 23 serotypes recovered. Most of the isolated serotypes are commonly associated with turkeys and have been incriminated as causative agents of human salmonellosis. The implication is that further-processed turkey products, if inadequately cooked by the consumer and if improperly refrigerated between the time of manufacture and consumption, could directly transmit salmonellae. These same products might also contaminate other foods by introducing salmonellae into food-preparation areas. PMID:5688832

  15. Process Intensification in Base-Catalyzed Biodiesel Production

    SciTech Connect

    McFarlane, Joanna; Birdwell Jr, Joseph F; Tsouris, Costas; Jennings, Hal L

    2008-01-01

    Biodiesel is considered a means to diversify our supply of transportation fuel, addressing the goal of reducing our dependence on oil. Recent interest has resulted in biodiesel manufacture becoming more widely undertaken by commercial enterprises that are interested in minimizing the cost of feedstock materials and waste production, as well as maximizing the efficiency of production. Various means to accelerate batch processing have been investigated. Oak Ridge National Laboratory has experience in developing process intensification methods for nuclear separations, and this paper will discuss how technologies developed for very different applications have been modified for continuous reaction/separation of biodiesel. In collaboration with an industrial partner, this work addresses the aspect of base-catalyzed biodiesel production that limits it to a slow batch process. In particular, we have found that interfacial mass transfer and phase separation control the transesterification process and have developed a continuous two-phase reactor for online production of a methyl ester and glycerol. Enhancing the mass transfer has additional benefits such as being able to use an alcohol-to-oil phase ratio closer to stoichiometric than in conventional processing, hence minimizing the amount of solvent that has to be recycled and reducing post-processing clean up costs. Various technical issues associated with the application of process intensification technology will be discussed, including scale-up from the laboratory to a pilot-scale undertaking.

  16. Parametric study of gas entry into cemented wellbores

    SciTech Connect

    Sabins, F.; Wiggins, M.L.

    1997-09-01

    A cement slurry is placed in a wellbore to harden into an impermeable mass that seals the annulus from fluid flow and protects the casing from corrosion for the life of the well. If fluid flow does occur in the form of gas migration, expensive remedial squeeze-cementing techniques are generally required. The objective of the work covered in this paper was to study the parameters that affect entry of gas into a cemented annulus. This research incorporated a detailed study of the factors that contribute to gas influx from the time of initial placement of the slurry, through the gelation or transition state of the slurry, to the set condition. On the basis of the understanding of the processes involved in gas entry, a simulator was developed that predicts the amount of gas that enters a cemented wellbore, and identifies the critical parameters that affect the gas entry. This study concerns itself with a portion of the gas flow problem: the entry of gas into a cemented annulus--and not with the flow of the gas up through the cement and the formation of a gas channel. This study will provide insight to the following questions. What cement properties are important to minimize gas entry? What role does fluid loss play in minimizing gas influx? What well parameters affect gas entry?

  17. Cementation of Upper Miocene reefs in western Mediterranean

    SciTech Connect

    Esteban, M.; Calvet, F.

    1983-03-01

    Coral reefs in the western Mediterranean (southeast Spain, Balearic Island, northern Morocco, Sicily, and Italy) show a wide variety of cement types, ranging from completely tight, well-cemented, to poorly cemented reefs with most of the primary porosity still preserved. Cementation processes in those coral reefs appear to be controlled to a great extent by repeated changes of relative sea levels and regional variations of seawater chemistry. Reef progradation occurred during four to six (or more) important sea level changes, resulting in complicated geometric relationships of reef complexes and their freshwater lenses. Progradation occurred during sea level rises and falls and is reflected in abrupt escarpments in some field localities, generally separated by important terraced erosional surfaces. Various types of aragonitic isopachous cement fringes of marine origin, 0.1 to 1.5 cm (.04 to .6 in.) thick, are well preserved in some localities. This is probably due to subsequent plugging by gypsum cement during the Messinian salinity crises. Another possible effect of salinity fluctuations is the abundance of thick crusts of peletoidal, micrite cement of marine origin, locally forming about three-fourths of the volume of the reef core.

  18. Influence of limestone on the hydration of Portland cements

    SciTech Connect

    Lothenbach, Barbara Le Saout, Gwenn; Gallucci, Emmanuel; Scrivener, Karen

    2008-06-15

    The influence of the presence of limestone on the hydration of Portland cement was investigated. Blending of Portland cement with limestone was found to influence the hydrate assemblage of the hydrated cement. Thermodynamic calculations as well as experimental observations indicated that in the presence of limestone, monocarbonate instead of monosulfate was stable. Thermodynamic modelling showed that the stabilisation of monocarbonate in the presence of limestone indirectly stabilised ettringite leading to a corresponding increase of the total volume of the hydrate phase and a decrease of porosity. The measured difference in porosity between the 'limestone-free' cement, which contained less than 0.3% CO{sub 2}, and a cement containing 4% limestone, however, was much smaller than calculated. Coupling of thermodynamic modelling with a set of kinetic equations which described the dissolution of the clinker, predicted quantitatively the amount of hydrates. The quantities of ettringite, portlandite and amorphous phase as determined by TGA and XRD agreed well with the calculated amounts of these phases after different periods of time. The findings in this paper show that changes in the bulk composition of hydrating cements can be followed by coupled thermodynamic models. Comparison between experimental and modelled data helps to understand in more detail the dominating processes during cement hydration.

  19. Plant-Wide Energy Efficiency Assessment at the Arizona Portland Cement Plant in Rillito, Arizona

    SciTech Connect

    Stephen J. Coppinger, P.E.; Bruce Colburn, Ph.D., P.E., CEM

    2007-05-17

    A Department of Energy Plant-wide Assessment was undertaken by Arizona Portland Cement (APC) beginning in May 2005. The assessment was performed at APC’s cement production facility in Rillito, Arizona. The assessment included a compressed air evaluation along with a detailed process audit of plant operations and equipment. The purpose of this Energy Survey was to identify a series of energy cost savings opportunities at the Plant, and provide preliminary cost and savings estimates for the work. The assessment was successful in identifying projects that could provide annual savings of over $2.7 million at an estimated capital cost of $4.3 million. If implemented, these projects could amount to a savings of over 4.9 million kWh/yr and 384,420 MMBtu/year.

  20. The effect of gyrolite additive on the hydration properties of Portland cement

    SciTech Connect

    Eisinas, A. Baltakys, K.; Siauciunas, R.

    2012-01-15

    The influence of gyrolite additive on the hydration properties of ordinary Portland cement was examined. It was found that the additive of synthetic gyrolite accelerates the early stage of hydration of OPC. This compound binds alkaline ions and serves as a nucleation site for the formation of hydration products (stage I). Later on, the crystal lattice of gyrolite becomes unstable and turns into C-S-H, with higher basicity (C/S {approx} 0.8). This recrystallization process is associated with the consumption of energy (the heat of reaction) and with a decrease in the rate of heat evolution of the second exothermic reaction (stage II). The experimental data and theoretical hypothesis were also confirmed by thermodynamic and the apparent kinetic parameters of the reaction rate of C{sub 3}S hydration calculations. The changes occur in the early stage of hydration of OPC samples and do not have a significant effect on the properties of cement stone.

  1. The influence of petroleum products on the methane fermentation process.

    PubMed

    Choroma?ski, Pawe?; Karwowska, Ewa; ?ebkowska, Maria

    2016-01-15

    In this study the influence of the petroleum products: diesel fuel and spent engine oil on the sewage sludge digestion process and biogas production efficiency was investigated. Microbiological, chemical and enzymatic analyses were applied in the survey. It was revealed that the influence of the petroleum derivatives on the effectiveness of the methane fermentation of sewage sludge depends on the type of the petroleum product. Diesel fuel did not limit the biogas production and the methane concentration in the biogas, while spent engine oil significantly reduced the process efficacy. The changes in physical-chemical parameters, excluding COD, did not reflect the effect of the tested substances. The negative influence of petroleum products on individual bacterial groups was observed after 7 days of the process, while after 14 days probably some adaptive mechanisms appeared. The dehydrogenase activity assessment was the most relevant parameter to evaluate the effect of petroleum products contamination. Diesel fuel was probably used as a source of carbon and energy in the process, while the toxic influence was observed in case of spent engine oil. PMID:26378365

  2. Evaluation of steel furnace slags as cement additives

    SciTech Connect

    Tuefekci, M.; Demirbas, A.; Genc, H.

    1997-11-01

    Chemical and physical properties and strength development have been studied for six granulated steel furnace slags from the normal steelmaking process. This paper reports results of research performed to develop cement mixture proportions using these slags. The influence of slag proportions, specific surface, and water demand on compressive strength and bulk density of cement blends are presented in this paper. The different test results, which were compared with the Turkish Standards, in general, were found to be within the limits.

  3. Laser processing of components for polymer mircofluidic and optoelectronic products

    NASA Astrophysics Data System (ADS)

    Gillner, Arnold; Bremus-Koebberling, Elke A.; Wehner, Martin; Russek, Ulrich A.; Berden, Thomas

    2001-06-01

    Miniaturization is one of the keywords for the production of customer oriented and highly integrated consumer products like mobile phones, portables and other products from the daily life and there are some first silicon made products like pressure sensors, acceleration sensors and micro fluidic components, which are built in automobiles, washing machines and medical products. However, not all applications can be covered with this material, because of the limitations in lateral and 3-dimensional structuring, the mechanical behavior, the functionality and the costs of silicon. Therefore other materials, like polymers have been selected as suitable candidates for cost effective mass products. This holds especially for medical and optical applications, where the properties of selected polymers, like biocompatibility, inert chemical behavior and high transparency can be used. For this material laser micro processing offers appropriate solutions for structuring as well as for packaging with high flexibility, material variety, structure size, processing speed and easy integration into existing fabrication plants. The paper presents recent results and industrial applications of laser micro processing for polymer micro fluidic devices, like micro analysis systems, micro reactors and medical micro implants, where excimer radiation is used for lateral structuring and diode lasers have used for joining and packaging. Similar technologies have been applied to polymer waveguides to produce passive optoelectronic components for high speed interconnection with surface roughness less than 20 nm and low attenuation. The paper also reviews the technical and economical limitations and the potential of the technology for other micro products.

  4. Operators tackle Anadarko cementing problems

    SciTech Connect

    Spradlin, W.N.

    1983-06-01

    Successful cementing in the deep Anadarko Basin, as in other deep producing provinces, requires meticulous attention to detail. Problems encountered during cementing operations include high temperature, high pressure, gas migration, and lost circulation. At times, these problems stretch the bounds of technology in rheological control of drilling mud and cement slurry. Although successful cementing techniques for Anadarko Basin deep wells present particular challenges, the principles involved also apply to other deep producing provinces. Deep well programs vary from one area of the Anadarko Basin to another. The variation is a function of the pressure encountered while drilling.

  5. Mapping asbestos-cement roofing with hyperspectral remote sensing over a large mountain region of the Italian Western Alps.

    PubMed

    Frassy, Federico; Candiani, Gabriele; Rusmini, Marco; Maianti, Pieralberto; Marchesi, Andrea; Rota Nodari, Francesco; Dalla Via, Giorgio; Albonico, Carlo; Gianinetto, Marco

    2014-01-01

    The World Health Organization estimates that 100 thousand people in the world die every year from asbestos-related cancers and more than 300 thousand European citizens are expected to die from asbestos-related mesothelioma by 2030. Both the European and the Italian legislations have banned the manufacture, importation, processing and distribution in commerce of asbestos-containing products and have recommended action plans for the safe removal of asbestos from public and private buildings. This paper describes the quantitative mapping of asbestos-cement covers over a large mountainous region of Italian Western Alps using the Multispectral Infrared and Visible Imaging Spectrometer sensor. A very large data set made up of 61 airborne transect strips covering 3263 km2 were processed to support the identification of buildings with asbestos-cement roofing, promoted by the Valle d'Aosta Autonomous Region with the support of the Regional Environmental Protection Agency. Results showed an overall mapping accuracy of 80%, in terms of asbestos-cement surface detected. The influence of topography on the classification's accuracy suggested that even in high relief landscapes, the spatial resolution of data is the major source of errors and the smaller asbestos-cement covers were not detected or misclassified. PMID:25166502

  6. Mapping Asbestos-Cement Roofing with Hyperspectral Remote Sensing over a Large Mountain Region of the Italian Western Alps

    PubMed Central

    Frassy, Federico; Candiani, Gabriele; Rusmini, Marco; Maianti, Pieralberto; Marchesi, Andrea; Nodari, Francesco Rota; Via, Giorgio Dalla; Albonico, Carlo; Gianinetto, Marco

    2014-01-01

    The World Health Organization estimates that 100 thousand people in the world die every year from asbestos-related cancers and more than 300 thousand European citizens are expected to die from asbestos-related mesothelioma by 2030. Both the European and the Italian legislations have banned the manufacture, importation, processing and distribution in commerce of asbestos-containing products and have recommended action plans for the safe removal of asbestos from public and private buildings. This paper describes the quantitative mapping of asbestos-cement covers over a large mountainous region of Italian Western Alps using the Multispectral Infrared and Visible Imaging Spectrometer sensor. A very large data set made up of 61 airborne transect strips covering 3263 km2 were processed to support the identification of buildings with asbestos-cement roofing, promoted by the Valle d'Aosta Autonomous Region with the support of the Regional Environmental Protection Agency. Results showed an overall mapping accuracy of 80%, in terms of asbestos-cement surface detected. The influence of topography on the classification's accuracy suggested that even in high relief landscapes, the spatial resolution of data is the major source of errors and the smaller asbestos-cement covers were not detected or misclassified. PMID:25166502

  7. Hierarchical production planning and energy modeling for food processing plants

    SciTech Connect

    Shah, S.A.

    1984-01-01

    The development of a generalized user-oriented multi-period, multi-resource production planning system for food processing plants is presented. The practical and computational aspects of the model for implementation are considered and some associated problems are solved. A distinguishing feature of this study is that the emphasis is given to the development of an operational and easy to implement framework as a managerial aid to production planning and scheduling. The procedure starts with an inter-active user-oriented program used to formulate the LP model and control food processing plant input data. This program is a link between the model formulation and plant data. Then the model is solved using a semi-commercial LP package MINOS. At this level, an optimal production plan is determined at an aggregate level. The production planning problem solution is very important and a necessary pre-requisite to the consideration of scheduling, design and/or energy modeling procedures. Examples are given in this study, using a fully integrated meat processing plant. Finally, the development of an energy utilization model for a food processing plant is described. The model is used to predict the time-of-day energy utilization of major processes in a meat processing plant.

  8. CO-PRODUCT ENHANCEMENT AND DEVELOPMENT FOR THE MASADA OXYNOL PROCESS PROCESS

    SciTech Connect

    Donald V. Watkins

    2010-06-14

    The focus of this project was an overall process improvement through the enhancement of the co-product streams. The enhancement of the process operations and co-products will increase both ethanol production and the value of other process outputs and reduces the amount of waste byproducts. This leads to a more economical and environmentally sound alternative to landfill disposal of municipal solid waste (MSW). These enhancements can greatly increase the commercial potential for the production of ethanol from MSW by the Masada CES OxyNol process. Both technological and economical issues were considered for steps throughout the conversion process. The research efforts of this project are varied but synergistic. The project investigated many of the operations involved in the Masada process with the overall goal of process improvements. The general goal of the testing was to improve co-product quality, improve conversions efficiencies, minimize process losses, increase energy efficiency, and mitigate process and commercialization risks. The project was divided into 16 subtasks as described in general terms below. All these tasks are interrelated but not necessarily interdependent.

  9. Process and reactor design for biophotolytic hydrogen production.

    PubMed

    Tamburic, Bojan; Dechatiwongse, Pongsathorn; Zemichael, Fessehaye W; Maitland, Geoffrey C; Hellgardt, Klaus

    2013-07-14

    The green alga Chlamydomonas reinhardtii has the ability to produce molecular hydrogen (H2), a clean and renewable fuel, through the biophotolysis of water under sulphur-deprived anaerobic conditions. The aim of this study was to advance the development of a practical and scalable biophotolytic H2 production process. Experiments were carried out using a purpose-built flat-plate photobioreactor, designed to facilitate green algal H2 production at the laboratory scale and equipped with a membrane-inlet mass spectrometry system to accurately measure H2 production rates in real time. The nutrient control method of sulphur deprivation was used to achieve spontaneous H2 production following algal growth. Sulphur dilution and sulphur feed techniques were used to extend algal lifetime in order to increase the duration of H2 production. The sulphur dilution technique proved effective at encouraging cyclic H2 production, resulting in alternating Chlamydomonas reinhardtii recovery and H2 production stages. The sulphur feed technique enabled photobioreactor operation in chemostat mode, resulting in a small improvement in H2 production duration. A conceptual design for a large-scale photobioreactor was proposed based on these experimental results. This photobioreactor has the capacity to enable continuous and economical H2 and biomass production using green algae. The success of these complementary approaches demonstrate that engineering advances can lead to improvements in the scalability and affordability of biophotolytic H2 production, giving increased confidence that H2 can fulfil its potential as a sustainable fuel of the future. PMID:23689756

  10. Modifying Yeast Tolerance to Inhibitory Conditions of Ethanol Production Processes

    PubMed Central

    Caspeta, Luis; Castillo, Tania; Nielsen, Jens

    2015-01-01

    Saccharomyces cerevisiae strains having a broad range of substrate utilization, rapid substrate consumption, and conversion to ethanol, as well as good tolerance to inhibitory conditions are ideal for cost-competitive ethanol production from lignocellulose. A major drawback to directly design S. cerevisiae tolerance to inhibitory conditions of lignocellulosic ethanol production processes is the lack of knowledge about basic aspects of its cellular signaling network in response to stress. Here, we highlight the inhibitory conditions found in ethanol production processes, the targeted cellular functions, the key contributions of integrated -omics analysis to reveal cellular stress responses according to these inhibitors, and current status on design-based engineering of tolerant and efficient S. cerevisiae strains for ethanol production from lignocellulose. PMID:26618154

  11. Quotation for the Value Added Assessment during Product Development and Production Processes

    E-print Network

    Alain Bernard; Nicolas Perry; Jean-Charles Delplace; Serge Gabriel

    2010-11-26

    This communication is based on an original approach linking economical factors to technical and methodological ones. This work is applied to the decision process for mix production. This approach is relevant for costing driving systems. The main interesting point is that the quotation factors (linked to time indicators for each step of the industrial process) allow the complete evaluation and control of, on the one hand, the global balance of the company for a six-month period and, on the other hand, the reference values for each step of the process cycle of the parts. This approach is based on a complete numerical traceability and control of the processes (design and manufacturing of the parts and tools, mass production). This is possible due to numerical models and to feedback loops for cost indicator analysis at design and production levels. Quotation is also the base for the design requirements and for the choice and the configuration of the production process. The reference values of the quotation generate the base reference parameters of the process steps and operations. The traceability of real values (real time consuming, real consumable) is mainly used for a statistic feedback to the quotation application. The industrial environment is a steel sand casting company with a wide mix product and the application concerns both design and manufacturing. The production system is fully automated and integrates different products at the same time.

  12. A novel method for immobilization of heavy metals from MSW incinerator fly ash via use of Sorel cement

    SciTech Connect

    Macakova, S.; Hepworth, M.H.

    1996-12-31

    Since fly ash contains a higher concentration of toxic elements than bottom ash, it is not usually possible to deposit it in ordinary landfills. The special landfill sites (ash monofills) for ash, which do not endanger ground water supplies are both temporary and an expensive solution and are not acceptable by people who live adjacent to them. According to the United States Supreme Court decision ruling on May 2, 1994, incinerator ash from municipal combustion facilities are subject to the Resource Conservation and Recovery Act as potentially hazardous waste. In the autumn of 1993, a research program was initiated by one of the authors to employ a novel method for stabilization of the fly ash from electrostatic precipitators. The novelty of this method is that it used by-products from magnesium processing plants to prepare magnesia cement, so called Sorel cement, to stabilize fly ash from MSWI. Sorel cement is a combination of magnesium oxide and magnesium chloride, currently by-products of a combination of magnesium oxide and magnesium chloride, currently by-products of magnesium processing operations. The main goal of this research program was to treat fly ash prior to its disposal and to investigate the possibility of utilizing a new ash-concrete product.

  13. Search for Polarization Effects in the Antiproton Production Process

    DOE PAGESBeta

    Grzonka, D.; Kilian, K.; Ritman, J.; Sefzick, T.; Oelert, W.; Diermaier, M.; Widmann, E.; Zmeskal, J.; G?owacz, B.; Moskal, P.; et al

    2015-01-01

    For the production of a polarized antiproton beam, various methods have been suggested including the possibility that antiprotons may be produced polarized which will be checked experimentally. The polarization of antiprotons produced under typical conditions for antiproton beam preparation will be measured at the CERN/PS. If the production process creates some polarization, a polarized antiproton beam could be prepared by a rather simple modification of the antiproton beam facility. The detection setup and the expected experimental conditions are described.

  14. Satellite Imagery Production and Processing Using Apache Hadoop

    NASA Astrophysics Data System (ADS)

    Hill, D. V.; Werpy, J.

    2011-12-01

    The United States Geological Survey's (USGS) Earth Resources Observation and Science (EROS) Center Land Science Research and Development (LSRD) project has devised a method to fulfill its processing needs for Essential Climate Variable (ECV) production from the Landsat archive using Apache Hadoop. Apache Hadoop is the distributed processing technology at the heart of many large-scale, processing solutions implemented at well-known companies such as Yahoo, Amazon, and Facebook. It is a proven framework and can be used to process petabytes of data on thousands of processors concurrently. It is a natural fit for producing satellite imagery and requires only a few simple modifications to serve the needs of science data processing. This presentation provides an invaluable learning opportunity and should be heard by anyone doing large scale image processing today. The session will cover a description of the problem space, evaluation of alternatives, feature set overview, configuration of Hadoop for satellite image processing, real-world performance results, tuning recommendations and finally challenges and ongoing activities. It will also present how the LSRD project built a 102 core processing cluster with no financial hardware investment and achieved ten times the initial daily throughput requirements with a full time staff of only one engineer. Satellite Imagery Production and Processing Using Apache Hadoop is presented by David V. Hill, Principal Software Architect for USGS LSRD.

  15. Study of two MTA cements

    PubMed Central

    Valmaseda-Castellón, Eduard; Faus, Vicente; Ballester, María-Luisa; Berini-Aytés, Leonardo

    2014-01-01

    Introduction: To determine and compare the pH, conductivity and calcium release of an experimental Portland cement (PE) consisting of trioxid mineral aggregate and a comercially available modified Portland cement (C.P.M.) after 1, 2, 3, 4, 8, 10, 15 and 30 days. Material and Methods: Cements were mixed following the manufacturer’s instructions, with a powder: liquid ratio of 3:1. Each cement was placed in 12 PVC tubes 1 mm in diameter and 10 mm in length and allowed to set. Four empty tubes were used as negative controls. Tubes were submerged in plastic flasks containing 10 ml deionized water and stored at 37ºC and 100% humidity. After 1, 2, 3, 4, 8, 10, 15 and 30 days tubes were removed from the flasks and these were refilled with deionized water. We measured pH, conductivity and calcium content of the recovered solution. Data were analyzed using repeated measures ANOVA. Results: pH was 0.3 units more alkaline with PE cement (p=0.023). pH experienced a slight decrease with time (p<0.001), independently of the cement type (p>0.05). Conductivity of PE and CPM cements diminished at 4 days and almost recovered at 30 days (p<0.001). PE cement had a higher conductivity (p<0.001). Calcium release diminished from the first day and recovered at 30 days (p<0.001) similarly for both cements (p>0.05). Conclusions: PE cement raised pH slightly more and had higher conductivity than CPM. Calcium release diminished after the first day and recovered at 30 days, similarly for both cements. Key words:Mineral trioxide aggregate, pH, electrical conductivity, periapical surgery. PMID:25350596

  16. Mechanics of aeolian processes: Soil erosion and dust production

    NASA Technical Reports Server (NTRS)

    Mehrabadi, M. M.

    1989-01-01

    Aeolian (wind) processes occur as a result of atmosphere/land-surface system interactions. A thorough understanding of these processes and their physical/mechanical characterization on a global scale is essential to monitoring global change and, hence, is imperative to the fundamental goal of the Earth observing system (Eos) program. Soil erosion and dust production by wind are of consequence mainly in arid and semi arid regions which cover 36 percent of the Earth's land surface. Some recent models of dust production due to wind erosion of agricultural soils and the mechanics of wind erosion in deserts are reviewed and the difficulties of modeling the aeolian transport are discussed.

  17. The Fractal Ratio as a Metric of Nanostructure Development in Hydrating Cement Paste

    NASA Astrophysics Data System (ADS)

    Livingston, R. A.; Bumrongjaroen, W.; Allen, A. J.

    It is necessary to have appropriate metrics to quantify the development of the nanostructure in Portland cement paste. The fractal ratio, calculated from Small Angle Neutron Scattering (SANS) data, serves as such a metric. It expresses the proportion of the volume-fractal surface area of calcium-silicate-hydrate gel (C-S-H) to the surface-fractal surface area. The volume fractal develops in the scale range from ? 5 nm to ? 100 nm, and it is associated with the formation of outer product in the capillary pore space by the through-solution mechanism. The surface fractal is attributed to the surface structure formed by colloidal particles on solid substrates such as the Portland cement grains and fly ash particles. The evolution of this ratio over time provides insight into which types of hydration processes are dominant. Applied to study of the hydration of fly ash/Portland cement mixes at later ages, the fractal ratio method showed that in every case, except two, there was a reduced hydration rate due to the dilution effect. The two exceptions involved fly ash fractions with sufficient CaO to generate significant C-S-H gel by the alkali-activated reaction. In all cases the fractal ratio increased with time, indicating the production of additional C-S-H through the topochemical reaction.

  18. A Review on Biomass Torrefaction Process and Product Properties

    SciTech Connect

    Jaya Shankar Tumuluru; Shahab Sokhansanj; Christopher T. Wright; J. Richard Hess; Richard D. Boardman

    2011-08-01

    Biomass Torrefaction is gaining attention as an important preprocessing step to improve the quality of biomass in terms of physical properties and chemical composition. Torrefaction is a slow heating of biomass in an inert or reduced environment to a maximum temperature of approximately 300 C. Torrefaction can also be defined as a group of products resulting from the partially controlled and isothermal pyrolysis of biomass occurring in a temperature range of 200-280 C. Thus, the process can be called a mild pyrolysis as it occurs at the lower temperature range of the pyrolysis process. At the end of the torrefaction process, a solid uniform product with lower moisture content and higher energy content than raw biomass is produced. Most of the smoke-producing compounds and other volatiles are removed during torrefaction, which produces a final product that will have a lower mass but a higher heating value. The present review work looks into (a) torrefaction process and different products produced during the process and (b) solid torrefied material properties which include: (i) physical properties like moisture content, density, grindability, particle size distribution and particle surface area and pelletability; (ii) chemical properties like proximate and ultimate composition; and (iii) storage properties like off-gassing and spontaneous combustion.

  19. Modeling the continuous lactic acid production process from wheat flour.

    PubMed

    Gonzalez, Karen; Tebbani, Sihem; Lopes, Filipa; Thorigné, Aurore; Givry, Sébastien; Dumur, Didier; Pareau, Dominique

    2016-01-01

    A kinetic model of the simultaneous saccharification, protein hydrolysis, and fermentation (SSPHF) process for lactic acid production from wheat flour has been developed. The model describes the bacterial growth, substrate consumption, lactic acid production, and maltose hydrolysis. The model was fitted and validated with data from SSPHF experiments obtained under different dilution rates. The results of the model are in good agreement with the experimental data. Steady state concentrations of biomass, lactic acid, glucose, and maltose as function of the dilution rate were predicted by the model. This steady state analysis is further useful to determine the operating conditions that maximize lactic acid productivity. PMID:26399412

  20. Mechanisms of Carbon Nanotube Production by Laser Ablation Process

    NASA Technical Reports Server (NTRS)

    Scott, Carl D.; Arepalli, Sivaram; Nikolaev, Pavel; Smalley, Richard E.; Nocholson, Leonard S. (Technical Monitor)

    2000-01-01

    We will present possible mechanisms for nanotube production by laser oven process. Spectral emission of excited species during laser ablation of a composite graphite target is compared with that of laser irradiated C60 vapor. The similarities in the transient and spectral data suggest that fullerenes are intermediate precursors for nanotube formation. The confinement of the ablation products by means of a 25-mm diameter tube placed upstream of the target seems to improve the production and purity of nanotubes. Repeated laser pulses vaporize the amorphous/graphitic carbon and possibly catalyst particles, and dissociate fullerenes yielding additional feedstock for SWNT growth.