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Clean energy from municipal solid waste. Technical progress report number 3

Description: Development of the computer models for slurry carbonization have begun and were based upon the collected data (mass balances, yield, temperatures, and pressures) from the previous pilot plant campaigns. All computer models are being developed with Aspen`s SpeedUp{trademark} software. The primary flow sheet with major alternatives has been developed and the majority of equipment descriptions and models, cost algorithms, and baseline parameters have been input to SpeedUp. The remaining modeling parameters will be input in the next reporting period and the initial flow sheet skeleton and model will be completed. The computer models will focus on optimizing capital and operating costs, and evaluating alternative waste water recycling technologies. The weaknesses of the previous pilot plant data and the data required for design of the commercial demonstration facility were identified. The identified weaknesses of the existing data included mass balance precision and accuracy, reactor residence time control (i.e. reactor level control), reactor temperature variations, and air entrainment in the feed RDF slurry. To improve mass balance precision and accuracy, an alternative carbonization gas flow meter will be designed and installed on the pilot plant. EnerTech`s carbonization gas flow meter design has been submitted to the EERC for final approval. In addition, an appropriate number of feed RDF samples will be characterized for moisture content just prior to the next pilot plant run to estimate incoming moisture variation. A pumping test also will be performed with the feed RDF slurry to determine the amount of air entrainment with the feed slurry.
Date: January 5, 1996
Creator: Klosky, M.
Partner: UNT Libraries Government Documents Department

Effect of coal beneficiation process on rheology/atomization of coal water slurries. Quarterly progress report, November 1, 1994--January 31, 1995

Description: The overall objective of this project is to perform experiments to understand the effect of coal beneficiation processes and high shear rheological properties on the atomization of coal-water slurries (CWS). In the atomization studies, the mean drop size of the CWS sprays will be determined at various air to CWS. A correlation between the high shear rheological properties, particle size distributions and the atomization will be made in order to determine the influence of these parameters on the atomization of CWS. During this past quarter, the atomization data obtained from the previous quarters were analyzed using a model equation that had previously been developed during the course of this work. The analysis demonstrates that there are two possible mechanisms for the breakup of the CWS. The first term of the equation is due to competition between surface tension forces and aerodynamic shearing force and the second term is due the competition between viscosity forces and surface tension force.
Date: October 1, 1995
Creator: Ohene, F.
Partner: UNT Libraries Government Documents Department

Design of atomizers and burners for coal water slurry combustion. Quarterly report, January 1, 1996--March 31, 1996

Description: A novel extensional rheotester was developed to measure the extensional properties of aqueous solutions of Polyacrilamide {number_sign}10 and coal water slurries (CWS). When a drop of viscoelastic liquid or CWS containing additives is allowed to form at the end of a capillary tube, it starts to fall once its weight exceeds the retaining force exerted by surface tension. In experiments with aqueous solutions of Polyacrilamide it was observed that a long filament of fluid connected the droplet to the end of the capillary tube. The filament partially supported the droplet slowing its rate of fall. In order to evaluate the transient elongational stresses an elongational viscosity that are developed in the long threads of liquid before breakup, the mass (m), the diameter (D), the velocity (V) and the acceleration (a) of the suspended droplet along with the diameter of the filament (d) are measured. The length of the trailing filament is also measured as a function of time in order to determine the filament stretch rate {dot {epsilon}}. The time dependent behavior of the filament diameter was also measured using a laser attenuation technique. The strain rate of the filament was determined from the experimental values of {dot L}/L and {minus}2{dot d}/d, where the dot refers to differentiation with respect to time. Seven different aqueous solutions of Polyacrilamide E10 were prepared spanning a wide range of polymer concentration (0.5{percent}, 0.25{percent}, 0. 125{percent}, 0.0625{percent}, 0.03125{percent}, 0.015625{percent}, 0. 0078125{percent}). The data gave a single relaxation time for each solution. This relaxation time for uniaxial extension is found to increase with E10 concentration. 4 refs., 10 figs., 2 tabs.
Date: September 1, 1996
Creator: Mansour, A. & Chigier, N.
Partner: UNT Libraries Government Documents Department

An investigation of computational modeling on phase distribution phenomena in vertical pipes

Description: A phase distribution phenomenon is observed in many gas/solid flows. An analysis of this phenomenon indicates that particle turbulence has a significant impact on the dispersion of particles in a vertical pipe flow. A new particle turbulent model has been developed to describe the phenomenon based on the inclusion of particle turbulence dynamics in transport equations. The main features of the model include an new transport equation of particle turbulent kinetic energy, a new expression of radial particle diffusion flux replacing Fick`s Law, and new turbulent viscosity correlation. The particle turbulent model was incorporated into a computational fluid dynamic code to predict particle dispersion in a vertical pipe flow. Preliminary results show the expected trend of particle accumulation near the wall.
Date: July 1, 1995
Creator: Bangxian Wu; Chang, S.L. & Lottes, S.A.
Partner: UNT Libraries Government Documents Department

Development of a coal fired pulse combustor for residential space heating. Technical progress report, April--June 1987

Description: During this period, advanced chambers were fabricated and tested in both single and tandem configurations. A scrubber was designed, constructed, installed in the facility, and checked-out. The dry pulverized coal and micronized coal water mixtures have been supplied by Energy International. Optimization of the configuration continued with respect to fuel phasing, slag handling characteristics, and tailpipe coupling.
Date: December 31, 1987
Partner: UNT Libraries Government Documents Department

Development of a coal fired pulse combustor for residential space heating: Phase 1-A. Technical progress report, June--August 1988

Description: The systematic development of the residential combustion system is divided into three phases. Only Phases I and IA are detailed here. Phase I constitutes the design, fabrication, testing, and evaluation of a pulse combustor sized for residential space heating. Phase IA includes additional testing with coal-water slurries and the design and evaluation of integrated systems using dry micronized coal and slurry. Phase II is an optional phase to develop an integrated system including a heat exchanger. Phase III is projected as a field test of the integrated coal-fired residential space heater. During this period, a combustor test bed was designed and fabricated to provide experimental resolution for the primary technical issues necessary to design and fabricate a fully integrated and optimized unit. A preliminary integrated design was also prepared and analytic models developed to simulate both steady-state performance and transient response during start-up and periodic cycling. The combustor test bed, ancillary facility components (including the wet cyclone scrubber), and sampling train were installed. Shakedown tests of the test bed were also initiated and a test plan is being prepared.
Date: October 1, 1988
Partner: UNT Libraries Government Documents Department

Task 4 -- Conversion to a coal-fueled advanced turbine system (CFATS)

Description: Solar is developing the technologies for a highly efficient, recuperated, Advanced Turbine System (ATS) that is aimed at the dispersed power generation market. With ultra-low-emissions in mind the primary fuel selected for this engine system is natural gas. Although this gas fired ATS (GFATS) will primarily employ natural gas the use of other fuels particular those derived from coal and renewable resources cannot be overlooked. The enabling technologies necessary to direct fire coal in gas turbines were developed during the 1980`s. This Solar development co-sponsored by the US Department of Energy (DOE) resulted in the testing of a full size coal-water-slurry fired combustion system. In parallel with this program the DOE funded the development of integrated gasification combined cycle systems (IGCC). This report describes the limitations of the Solar ATs (recuperated engine) and how these lead to a recommended series of modifications that will allow the use of these alternate fuels. Three approaches have been considered: direct-fired combustion using either a slagging combustor, or a pressurized fluidized bed (PFBC), externally or indirectly fired approaches using pulverized fuel, and external gasification of the fuel with subsequent direct combustion of the secondary fuel. Each of these approaches requires substantial hardware and system modifications for efficient fuel utilization. The integration issues are discussed in the sections below and a recommended approach for gasification is presented.
Date: April 15, 1996
Partner: UNT Libraries Government Documents Department

Advanced atomization concept for CWF burning in small combustors, Phase 2

Description: The program describes a concept referred to as opposed-jet atomization, which is particularly applicable to coal-water fuel (CWF). In the present atomizer design, two opposed jets of CWF are directed at each other and externally encounter a perpendicular blast of air at the collision point to create a spray of much finer droplets. The present Phase 2 program involved further evaluation of the opposed-jet atomizer performance and related tasks.
Date: December 1, 1991
Creator: McHale, E.T. & Heaton, H.L.
Partner: UNT Libraries Government Documents Department

Confirmation test for gas/slurry flow in SRC-I coal liquefaction process. Internal R and D final report

Description: The overall objective of program 12.11.1 was to provide data needed to confirm the design of the transport system, slurry heat exchangers, and slurry feed manifolds for the SRC-I Demonstration Plant. Because of lack of funds, the program was terminated before most of the work was completed. Two studies related to distribution of two-phase flow in the heat exchanger tubes were finished. A special system was designed to measure slurry concentration and flow rate in different tubes. Results showed that withdrawing slurry samples from the sides of the tubes gives a reasonably accurate measure of the concentration. Flow rate was measured indirectly with a photodiode/digital counter arrangement that measured velocity of a gas slug injected in the tube. A simple linear correlation was found to exist between the average slurry velocity and the gas-slug velocity. 1 reference, 25 figures.
Date: September 1, 1983
Creator: Moujaes, S.F.
Partner: UNT Libraries Government Documents Department

NEUTRON FLUX AND Cd RATIO MEASUREMENTS IN THE HN-1 BEAM HOLE FOR THREE FUEL LOADINGS OF THE OAK RIDGE RESEARCH REACTOR

Description: Neutron flux measurements were made in the Oak Ridge Research Reactor beam hole HN-l shield plug. at low reactor power (N/sub L/) with three fuel configurations. The purpose of these tests was to determine the most favorable fuel arrangement in the region of the experimental hole in order to permit minimization of exposure time of an in-pile slurry loop experiment using pure thoria. It was found that the perturbed thermal neutron flux decreased by factors of 2, each 1.4 in., at the forward end of the beam hole. Maximum and average fluxes observed for three fuel configurations were: high, 9.7 x l0/sup 13/ , 5.6 x 10/sup 13/; intermediate, 8.0 x 10/sup 13/, 4.7 x l0/sup 13/; and present operating, 7.4 x l0/sup 13/, 3.8 x 10/sup 13/. In the high and intermediate configurations fuel elements were located in the outer row of the lattice adjacent to the beam hole. Cadmium ratios were generally high (22 to 111) implying low available epi-cadmium flux under any of these configurations. (auth)
Date: October 10, 1961
Creator: Shor, A.J.f Mauney, T.H.
Partner: UNT Libraries Government Documents Department

A novel method of atomizing coal-water slurry fuels

Description: Despite the body of work describing the performance of effervescent atomizers, its potential for use with coal water slurries (CWS) had not been evaluated prior to this study. This program was therefore undertaken: to demonstrate that effervescent atomization can produce CWS sprays with mean drop sizes below 50{mu}m; to determine a lower size limit for effervescent atomizer produced CWS sprays; to determine the mechanism(s) responsible for the formation of effervescent atomizer produced sprays. An analysis of the effects of slurry rheological properties (as indicated by the consistency index and the flow behavior index) and formulation (in terms of loading and coal particle top size) on the spray formation process was performed. The experimental data reported were then analyzed to explain the physical processes responsible for spray formation. The analysis began by considering an energy balance across a control volume that extended from the nozzle exit plant to the line of spray measurement. The inlet conditions were calculated using two-phase flow techniques and the outlet conditions were calculated by using conservation of momentum and assuming that the final velocities of the air and liquid were equal. Entrainment was considered negligible and losses were accounted for by realizing that only a small fraction of the atomizing air participated in the spray formation process with the remainder passing through the control volume unperturbed. Results are discussed. 41 figs., 4 tabs.
Date: May 1, 1990
Creator: Sojka, P.E. & Lefebvre, A.H.
Partner: UNT Libraries Government Documents Department

Correlation of stability/rheology relationship with coal properties and chemical additives

Description: The overall objective of this project is to perform experiments to evaluate the necessary boundary conditions in the preparation and utilization of Coal Water Slurries (CWS) and also develop a data base for the conceptual analysis of a prescription to predict slurry quality for a given coal candidate. This quarter, zeta potential and static stability measurements of three coal slurries have been made using poly naphthalene ammonium sulphonate, A-23, A-23S MCG-32A-LS and Igepal 990 as dispersants and at a pH of 10. A preliminary study of the static stability measurements were made in a column having two outlet ports separated by a distance of 1 ft. Samples were withdrawn periodically from these ports and the solid content profile was determined for an initial period of one week. Based on the results obtained from this preliminary study, larger samples were prepared and the stability measurements made in a 6 ft column having three outlet ports with a water jacket surrounding it. Zeta Potential measurements were made prior to the stability studies. 1 tab.
Date: January 1, 1990
Creator: Ohene, F.
Partner: UNT Libraries Government Documents Department

Correlation of stability/rheology relationship with coal properties and chemical additives

Description: A methodology has been developed in order to determine the influence of individual particle size fractions on coal water slurry rheology. This involves the determination of the packaging concentrations and rheology of the separate particle size fractions; {minus}400 mesh, {minus}400/325, {minus}325/270, {minus}270/200 mesh, {minus}200/140 mesh, {minus}140/100 mesh and {minus}100/80 mesh as a function of solids loading. The packaging concentrations of the separate particle size fractions and that of several blends of these sizes have been determined. The packaging concentrations were determined from particle size distribution measurements and a program based on truncated log-normal distribution which has been developed at the Adelphi Center for Energy Studies. 5 refs., 7 figs., 10 tabs.
Date: January 1, 1990
Creator: Ohene, F.
Partner: UNT Libraries Government Documents Department

Correlation of stability/rheology relationship with coal properties and chemical additives

Description: Four coal samples are being used to test the fundamental relationship between coal properties and slurryability that has been established in this work. Rheological properties have been performed on these samples. Several chemical additives were tested for their effect on slurryability. 1 ref., 1 tab.
Date: January 1, 1991
Creator: Ohene, F.
Partner: UNT Libraries Government Documents Department

Coal diesel combined-cycle project. Annual report, January 1996--January 1997

Description: The Clean Coal Diesel project will demonstrate a new Clean Coal Technology that has technical, economic and environmental advantages over conventional power generating methods. This innovative technology enables utilization of coal-based fuel in large-bore, medium-speed, diesel engines. Modular power generating applications in the 10 to 100 megawatt size range are the target applications. The University of Alaska campus in Fairbanks, Alaska, is the project`s host site. At this location, the University will construct and operate the Clean Coal Diesel System, which will serve as a 6.2 MW diesel powerplant addition. The University will also assemble and operate a 5-ton per hour coal-water fuel processing plant. The plant will utilize local coal, brought by truck from Usibelli`s mine in Healey, AK. The estimated performance characteristics of the mature commercial embodiment of the Clean Coal Diesel, if achieved, will make this technology quite competitive: 48% efficiency; $1,300/kW installed cost; and emission levels controlled to 50--70% below New Source Performance Standards. Specific objectives are to demonstrate that the Coal Diesel Technology: is durable and can operate 6,000 hours in a realistic commercial setting; will meet efficiency targets; can effectively control criteria pollutants to levels that are well below anticipated standards, as well as reduce greenhouse gas emissions; and can accommodate substantial power demand swings.
Date: December 31, 1997
Partner: UNT Libraries Government Documents Department

Engineering development of advanced physical fine coal cleaning for premium fuel applications

Description: This project is a step in the Department of Energy's program to show that ultra-clean fuel can be produced from selected coals and that the fuel will be a cost-effective replacement for oil and natural gas now fueling boilers in this country. The replacement of premium fossil fuels with coal can only be realized if retrofit costs are kept to a minimum and retrofit boiler emissions meet national goals for clean air. These concerns establish the specifications for maximum ash and sulfur levels and combustion properties of the ultra-clean coal. The primary objective is to develop the design base for prototype commercial advanced fine coal cleaning facilities capable of producing ultra-clean coals suitable for conversion to coal-water slurry fuel. The fine coal cleaning technologies are advanced column flotation and selective agglomeration. A secondary objective is to develop the design base for near-term commercial integration of advanced fine coal cleaning technologies in new or existing coal preparation plants for economically and efficiently processing minus 28-mesh coal fines. A third objective is to determine the distribution of toxic trace elements between clean coal and refuse when applying the advance column flotation and selective agglomeration technologies. The project team consists of Amax Research Development Center (Amax R D), Amax Coal industries, Bechtel Corporation, Center for Applied Energy Research (CAER) at the University of Kentucky, and Arcanum Corporation.
Date: January 18, 1993
Creator: Smit, F.J. & Jha, M.C.
Partner: UNT Libraries Government Documents Department

Data review and operating experience evaluation of the SRC II process

Description: Scientific Design Company (SD) has reviewed the Ft. Lewis pilot plant operation and data gathered in the SRC II Solvent Refined Coal (liquid fuel production) program, which tested Kentucky, Illinois, and Pittsburgh Seam coals. The aim of this review is to further the understanding of the process, help to evaluate its potential and assist the Department of Energy (DOE) in future development decisions. The major conclusions that SD has reached are summarized: Extensive and varied operating experience gained in the program has demonstrated the basic feasibility and stability of the process. A high on-stream factor was achieved throughout the program and the reaction section showed no tendency to plug or coke. The total data base, including all of the data which Gulf obtained at its Harmarville laboratory in conjunction with published information obtained at Ft. Lewis, could be used to design a commercial plant with reasonable confidence, within the range of variables explored. The equipment, procedures and programs of Ft. Lewis to date have not been appropriate to the gathering of complete process development data. This multi-functional plant is better suited to its other tasks of demonstrating the basic operability of the process, testing components, and accumulating large product and residue samples for combustion and gasification tests. This report points out the types of necessary additional process development data, obtainable in pilot plants, which would be needed for a commercial plant design. It is essential that all future data analysis and pilot plant operation in the SRC II development effort should be directed toward what is needed for a commercial plant design.
Date: September 1, 1978
Creator: Beskind, M.M. & Cascone, R.F.
Partner: UNT Libraries Government Documents Department

[Roles of additives and surface control in slurry atomization]

Description: As reported in the quarterly report of March of 1992, the relative viscosity of a Newtonian Coal Water Slurry (CWS) in the presence of an anionic polymeric dispersant is an order of magnitude higher than the prediction of the well established Krieger-Dougherty Equation which describes the relative viscosity of a non-aggregated Newtonian suspension as a function of particle volume fraction. Note that the anionic dispersant is used in such a quantity that the resulting interparticle electrostatic repulsion counter-balances the interparticle van der Waals attraction. Investigation continues to determine the mechanisms of such excess energy dissipation under shear. New experimental results are presented in this report to verify the role of the anionic polymeric dispersant in such excess energy dissipation of CWS.
Date: June 1, 1992
Creator: Tsai, S.C.
Partner: UNT Libraries Government Documents Department

Roles of additives and surface control in slurry atomization

Description: This project studies the rheology and airblast atomization of micronized coal slurries. Its major objectives are (1) to promote further understanding of the mechanisms and the roles of additives in airblast atomization of coal water slurry (CWS), and (2) to investigate the impacts of coal particle surface properties and interparticle forces on CWS rheology. We have found that the flow behavior index (n) of a suspension (or slurry) is determined by the relative importance of the interparticle van der Waals attraction and the interparticle electrostatic repulsion. The interparticle attraction, measured by the Hamaker constant scaled to the thermal energy at 25[degrees]C (A/kT), causes particle aggregation, which breaks down at high shear rates, and thus leads to slurry pseudoplastic behavior (n< 1). At a constant particle volume fraction and surface charge density (qualitatively measured by the zeta potential in deionized water), n decreases linearly as A/kT increases. The relative viscosity of the pseudoplastic suspension with respect to that of the suspending liquid is found to be independent of particle density and correlate well with the particle Peclet number which equals the particle diffusional relaxation time multiplied by shear rate. Specifically, the relative viscosities of the pseudoplastic glycerol/water coal slurry and the ethylene glycol/glycerol sand slurry, at same volume fractions as well as similar particle size distributions and liquid viscosities, as functions of the particle Peclet number fall along the same line.
Date: January 1, 1992
Creator: Tsai, S.C.
Partner: UNT Libraries Government Documents Department

Roles of additives and surface control in slurry atomization

Description: This quarterly report describes a quantitative correlation between the flow behavior index of a micronized coal slurry and the interparticular van der Waals attraction force as measured by the Hamaker constant. Preliminary results on the effects of interparticular electrostatic repulsion and the liquid viscosity on both the flow behavior and the relative viscosity are also presented.
Date: March 1, 1990
Creator: Tsai, S.C.
Partner: UNT Libraries Government Documents Department

Gasifier feed: Tailor-made from Illinois coals. Technical report, September 1, 1991--November 30, 1991

Description: The purpose of this research is to develop a coal slurry from waste streams using Illinois coal that is ideally suited for a gasification feed. The principle items to be studied are (1) methods of concentrating pyrite and decreasing other ash forming minerals into a high grade gasification feed using froth flotation and gravity separation techniques; (2) chemical and particle size analyses of coal slurries; (3) determination of how that slurry can be densified and to what degree of densification is optimum from the pumpability and combustibility analyses; and (4) reactivity studies.
Date: December 31, 1991
Creator: Ehrlinger, H. P. III
Partner: UNT Libraries Government Documents Department

Testing of a coal-fired diesel power plant

Description: The POC coal-fired power plant consists of a Cooper-Bessemer LSC-6 engine (15.5 inch bore, 22 inch stroke) rated at 400 rev/min and 208 psi bmep producing approximately 1.8 MW of power. The power plant is fueled with `engine grade` coal slurry which has been physically cleaned to an ash level of approximately 1.5 to 2% (dry basis) and has a mean particle size of approximately 12 micron. CWS is injected directly into the combustion chamber through a fuel injector (one per cylinder) which was designed and developed to be compatible with the fuel. Each injector is fitted with a 19 orifice nozzle tip made with sapphire inserts in each orifice. The combustion chambers are fitted with twin diesel pilot injectors which provide a positive ignition source and substantially shorten the ignition delay period of the CWS fuel. Durable coatings (typically tungsten carbide) are used for the piston rings and cylinder liners to reduce wear rates. The emission control system consists of SCR for NO{sub x} control, sodium sorbent injection for SO{sub x} control, and a cyclone plus baghouse for particulate capture. The cyclone is installed upstream of the engine turbocharger which helps protect the turbine blades.
Date: January 1, 1993
Creator: Wilson, R. P.; Balles, E. N.; Benedek, K. R.; Benson, C. E.; Rao, K.; Schaub, F. et al.
Partner: UNT Libraries Government Documents Department

CFBC evaluation of fuels processed from Illinois coals. Technical report, September 1, 1991--November 30, 1991

Description: The overall objectives for this one-year project are: (1) to demonstrate that new fuels derived from Illinois high sulfur coal, namely (a) coal-sorbent pellets and (b) coal-water slurry produced from froth flotation feed can be effectively utilized in a circulating fluidized bed combustor, (2) to compare the carbon conversion efficiencies, SO{sub 2} and NO{sub x} emission levels and Ca/S ratios needed to meet EPA regulations from the above fuels with those measured under similar operating conditions with a standard IBCSP coal, and (3) to analyze ash and spent limestone residues with a view to proposing waste disposal strategies for the combustion residues resulting from these new fuel forms.
Date: December 31, 1991
Creator: Rajan, S.
Partner: UNT Libraries Government Documents Department