Browse Topic: Coal

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Low-Order Prediction of Mineral Dust Sticking Probability in Turboshaft EnginesF-0076-2020-1633810/5/2020
ABSTRACT Rotorcraft operations in arid environments can result in the ingestion of large quantities of dust particles into turboshaft engines, where they can melt and deposit on high pressure turbine nozzle guide vanes. This can result in reduced engine life-span and in worst case scenarios, in-flight engine failure. Predicting the extent and rate at which this damage occurs has proven difficult owing to the wide range of variables relating to the dust cloud, engine and most importantly, the properties of the particulate encountered. Whilst significant work has been carried out to model the particle deposition process for both volcanic ash and coal fly-ash, there is scarce similar work for the different types of mineral dusts rotorcraft encounter. In this contribution, we assess the suitability of two opposing numerical approaches for use in a generalised, reduced-order deposition model of individual mineral particles depositing on a vane. Both models are seen to be heavily reliant upon empirical inputs, be this the thermo-mechanical properties of the particles such as their yield strength, or currently unknown experimentally determined constants. An alternative approach is therefore proposed whereby the particle yield strength is correlated using existing relationships to the Vickers hardness of the grain, a property more amenable to empirical determination. The results obtained represent the current applicability limits of the two models based upon existing empirical data and thus highlight the need for further experimentation relating to both the thermo-mechanical properties and probabilities of adhesion for both individual mineral grains and mineral dust blends.
Ellis, Matthew, Bojdo, Nicholas, Filippone, Antonio, Jones, Merren, Pawley, Alison
History and Prospects for Electric Vehicles and Electric Bikes: Pathway to Sustainable Carbon Free Energy and Transportation2020-01-09744/14/2020
The Electric Transportation Revolution (ETR) began with the General Motors USA EV1 project and Yamaha Japan Pedal Assist System (PAS) electric bike, both in 1993. Worldwide EB annual sales are 40 million with 300 million on the road, mostly in China. Mandates and government incentives influence the EV market, customer demand drives EB growth. The EPA CO2 endangerment finding is forcing the auto industry to invest in EVs to help limit Mankind Made Carbon Dioxide Climate Change, MMCDCC, which is based on theoretical computer models that calculate global temperature. Measured temperature data, revised by modelers, used to validate these models has been challenged and so reported. Historical climatology data shows that Natural Climate Change, NCC, is more likely the CC cause. Known periodic variations of the sun’s orbit changes solar radiance and causes NCC. More CO2 in the atmosphere produces more plant growth, more food, thus CO2 is a beneficial gas. We propose a long term pathway to eliminate CO2 as an issue for energy and transportation. Fossil fuels may be depleted in 200 years. During this period, transition worldwide to nuclear power and hydrogen for electricity and transportation is necessary. Nuclear fuels will be used forever as uranium extraction from seawater is now possible and is replenished by runoff from land. Nuclear electricity will produce hydrogen from electrolysis of water for vehicle use. Power plants and vehicles will thus not produce CO2. With this prospect of sustainable carbon free electricity and vehicle fuel, the humanitarian thing to do today is to continue to use fossil fuels for both domains, in order to provide affordable heat in cold winters and cooling in hot summers which occurs in some regions of the world today until nuclear options are developed. This all is likely NCC as it has been for hundreds of millions of years on planet earth, and not MMCDCC.
Jamerson, Frank E.
The Nozzle Flows and Atomization Characteristics of the Two-Component Surrogate Fuel of Diesel from Indirect Coal Liquefaction at Engine Conditions2018-01-16919/10/2018
Recently, all world countries facing the stringent emission regulations have been encouraged to explore the clean fuel. The diesel from indirect coal liquefaction (DICL) has been verified that can reduce the soot and NOx emissions of compression-ignition engine. However, the atomization characteristics of DICL are rarely studied. The aim of this work is to numerically analyze the inner nozzle flow and the atomization characteristics of the DICL and compare the global and local flow characteristics of the DICL with the NO.2 diesel (D2) at engine conditions. A surrogate fuel of the DICL (a mixture of 72.4% n-dodecane and 27.6% methylcyclohexane by mass) was built according to its components to simulate the atomization characteristics of the DICL under the high-temperature and high-pressure environment (non-reacting) by the Large Eddy Simulation (LES). The simulation results show that the DICL is more likely to form cavitation compared with D2, and the turbulence level at the orifice exit is larger for DICL. The liquid penetration of DICL is shorter than that of D2, while the vapor penetrations between DICL and D2 have no obvious difference. The spray cone angle of DICL is larger than that of D2. In addition, the gas-phase axial velocity of the DICL along the spray center line is slightly larger than that of D2 in the upstream of the spray. Moreover, the SMD of the DICL is larger than that of D2. Generally, this study is helpful to understand the differences in the inner nozzle flow features and the atomization characteristics between DICL and D2.
Huang, Zhong, Zhang, Wenzheng, Xia, Jin, Ju, Dehao, Han, Dong, Lu, Xing-Cai
Chemical Kinetics and Computational Fluid-Dynamics Analysis of H 2 /CO/CO 2 /CH 4 Syngas Combustion and NOx Formation in a Micro-Pilot-Ignited Supercharged Dual Fuel Engine2017-24-00279/4/2017
A chemical kinetics and computational fluid-dynamics (CFD) analysis was performed to evaluate the combustion of syngas derived from biomass and coke-oven solid feedstock in a micro-pilot ignited supercharged dual-fuel engine under lean conditions. For this analysis, a reduced syngas chemical kinetics mechanism was constructed and validated by comparing the ignition delay and laminar flame speed data with those obtained from experiments and other detail chemical kinetics mechanisms available in the literature. The reaction sensitivity analysis was conducted for ignition delay at elevated pressures in order to identify important chemical reactions that govern the combustion process. We have confirmed the statements of other authors that HO2+OH=H2O+O2, H2O2+M=OH+OH+M and H2O2+H=H2+HO2 reactions showed very high sensitivity during high-pressure ignition delay times and had considerable uncertainty. The chemical kinetics of NOx formation was analyzed for H2/CO/CO2/CH4 syngas mixtures by using counter flow burner and premixed laminar flame speed reactor. The new mechanism showed a very good agreement with experimental measurements and accurately reproduced the effect of pressure, temperature and equivalence ratio on NOx formation. In order to identify the species important for NOx formation, a sensitivity analysis was conducted for pressures 4 bar, 10 bar and 16 bar and preheat temperature 300 K. The results show that the NOx formation is driven mostly by hydrogen based species while other species, such as N2, CO2 and CH4, have also important effects on combustion. Finally, the new mechanism was used in a multidimensional CFD simulation to predict the combustion of syngas in a micro-pilot-ignited supercharged dual-fuel engine and results were compared with experiments. The mechanism showed the closest prediction of the in-cylinder pressure and the rate of heat release (ROHR).
Stylianidis, Nearchos, Azimov, Ulugbek, Kawahara, Nobuyuki, Tomita, Eiji
Nick Krotkov, Atmospheric Scientist, Goddard Space Flight Center, Greenbelt, MDTBMG-269345/22/2017
Using data from NASA’s Earth Observing System Aura satellite, launched in 2004, a team led by Michigan Technological University created a global map of volcanic emissions. Scientist Nick Krotkov will use the information to refine climate models and better understand the human and environmental health risks of erupted gases like sulfur dioxide.
Development of a Surrogate for SASOL IPK and Its Validation in Ignition Quality Tester2017-01-02633/28/2017
SASOL IPK is a low cetane number synthetic fuel formed from coal by the Fischer-Tropsch process which can be used as an extender to JP8, currently used in military ground vehicles. This paper presents two surrogates developed considering the following criteria: (a) availability of kinetic combustion models for each component, (b) smallest number of components to reduce computation time and cost, (c) matching the following properties of target fuel DCN, distillation curve, density, LHV, MW and H/C ratio. The autoignition and combustion characteristics of the surrogates were validated in IQT according to ASTM D6890-10a. Surrogate formulation strategy involves an equation to calculate DCN of the surrogate mixture from the DCN of each component. The linear equation commonly used for such calculations was modified to include a multiplier, based on regression analysis, for each component to produces DCN values that agree well with the measured DCN in the IQT.
Udayachalam, Krishnaraj, Trivedi, Manan, Zheng, Ziliang, Shrestha, Amit, Henein, Naeim
Advanced Supported Liquid Membranes for CO‚2 Control in EVA ApplicationsTBMG-238652/1/2016
This sorbent can be used in the capture of CO2 from coal-fired power plants and other power generation facilities.
Information on the Aromatic Structure of Internal Diesel Injector Deposits From Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS)2014-01-13874/1/2014
The nature of internal diesel injector deposits (IDID) continues to be of importance to the industry, with field problems such as injector sticking, loss of power, increased emissions and fuel consumption being found. The deposits have their origins in the changes in emission regulations that have seen increasingly severe conditions experienced by fuels because of high temperatures and high pressures of modern common rail systems and the introduction of low sulphur fuels. Furthermore, the effect of these deposits is amplified by the tight engineering tolerances of the moving parts of such systems. The nature and thus understanding of such deposits is necessary to both minimising their formation and the development of effective diesel deposit control additives (DCA). The focused ion beam technique coupled with time of flight secondary -ion mass spectrometry (ToF-SIMS) has the ability to provide information on diesel engine injector deposits as a function of depth for both organic and inorganic constituents. Our previous work with this novel technique is unique in that it has shown layering effects in deposits which may be due to the residual fuel either evaporating and leaving residues or being unable to keep insoluble residues in solution during the injection process. As part of our on-going work to understand the nature of field deposits, the aromatic compounds present have been investigated. To help interpret the results for the aromatic structures present, spectra of a model polycyclic aromatic hydrocarbon (PAH), coronene (C24H12), and coal tar pitch (CTP) have been used as a basis to determine the ring structure of internal diesel; deposits. This work confirms the presence of aromatic ring structures of greater than six rings in composition in injector needle carbonaceous deposits.
Barker, Jim, Snape, Colin, Scurr, David
The Future Adoption and Benefit of Electric Vehicles: A Parametric Assessment2013-01-05024/8/2013
We present a parametric analysis of electric vehicle (EV) adoption rates and the corresponding contribution to greenhouse gas (GHG) reduction in the US light-duty vehicle (LDV) fleet through 2050. The analysis is performed with a system dynamics based model of the supply-demand interactions among the fleet, its fuels, and the corresponding primary energy sources. The differentiating feature of the model is the ability to conduct global sensitivity and parametric trade-space analyses. We find that many factors impact the adoption rates of EVs. These include, in particular, policy initiatives that encourage consumers to consider lifetime ownership costs, the price of oil, battery performance, as well as the pace of technological development for all powertrains (conventional internal combustion engines included). Widespread EV adoption can have noticeable impact on petroleum consumption and GHG emissions by the LDV fleet. However, EVs alone cannot drive compliance with the most aggressive GHG emission reduction targets, even as the electricity source mix shifts away from coal and towards natural gas. Since vehicles with traditional internal combustion engines (ICEs) will comprise the majority of the LDV fleet for up to forty years, conventional vehicle efficiency improvements have the greatest potential for reductions in LDV GHG emissions over this time.
Barter, Garrett E., Reichmuth, David, West, Todd H., Manley, Dawn K.
Regenerable Sorbent for CO2 RemovalTBMG-161254/1/2013
A durable, high-capacity regenerable sorbent can remove CO2 from the breathing loop under a Martian atmosphere. The system design allows nearambient temperature operation, needs only a small temperature swing, and sorbent regeneration takes place at or above 8 torr, eliminating the potential for Martian atmosphere to leak into the regeneration bed and into the breathing loop. The physical adsorbent can be used in a metabolic, heat-driven TSA system to remove CO2 from the breathing loop of the astronaut and reject it to the Martian atmosphere. Two (or more) alternating sorbent beds continuously scrub and reject CO2 from the spacesuit ventilation loop. The sorbent beds are cycled, alternately absorbing CO2 from the vent loop and rejecting the adsorbed material into the environment at a high CO2 partial pressure (above 8 torr). The system does not need to run the adsorber at cryogenic temperatures, and uses a much smaller temperature swing.
Selection of the Most Promising Alternative Fuels for Aircraft Development: ALFA-BIRD Proposal2011-01-279110/18/2011
Air traffic has been steadily increasing for the last years. Moreover, fuel availability at a reasonable cost seems more and more uncertain. Climate change implies that greenhouse gases emissions should be reduced. In this context, the search for new alternative fuels for aircraft seems to be a promising solution. Nevertheless, aeronautic represents a very specific transportation mode, due to its usage (short range, middle range, long range with the same fuel, worldwide distribution of the fuel…) and its compulsory security constraints. In the first part of the European project ALFA-BIRD (Alternative Fuels and Biofuels for Aircraft development - FP7), a selection of the best candidates to become the fuels for the future of aircraft has been done. The selection process was very complex, due to multiple criteria (physical properties, economical issued, environmental issues…). A first matrix of 12 blends has been defined including: FSJF (Fully Synthetic Jet Fuel), FT-SPK (Fischer-Tropsch Synthetic Paraffinic Kerosene), Naphthenic cut, HVO (Hydrotreated Vegetable Oils), hexanol, furane and FAE (Fatty Acid Esters) in different amounts. The FSJF consists of 50% FT-SPK and 50% of severely hydrogenated coal tar kerosene. FT-SPK and HVO are paraffinic compounds. FT-SPK fuels are well known products and a huge work has already been done to certify this product, leading to ASTM D7566. Moreover, there is a strong potential in term of availability due to multiple sources (Biomass, Coal, Gas, Waste). HVO displays chemical composition and physical properties close to FT-SPK ones, but their certification for aircraft use is still under discussion in May 2011 and could lead to a standardization before the end of the year. The naphthenic compounds represent products that come from direct liquefaction/pyrolysis of coal or biomass. Concerning the oxygenated compounds, the study of their potential use in aeronautics is very original and can be considered as a long-term view. This first fuel matrix of 12 blends were evaluated following the standard jet fuel characterization. Thanks to this first study, 4 fuels were pointed out : FSJF, FT-SPK, a blend of FT-SPK and 50% naphthenic cut, and a blend of FT-SPK and 20% hexanol. This fuel matrix allows evaluating the potential of several chemical families: paraffinic, naphthenic and oxygenated compounds. This is also representative of a short, middle, and long term views. These 4 fuels will be deeply evaluated in term of combustion, material compatibility, stability during the second part of the ALFA-BIRD project.
Pidol, Ludivine, Starck, Laurie, Jeuland, Nicolas, Allouche, Yohan
Reducing Aerodynamic Drag on Empty Open Cargo VehiclesTBMG-55178/1/2009
Some simple structural modifications have been demonstrated to be effective in reducing aerodynamic drag on vehicles that have empty open cargo bays. The modifications were originally intended to be made in railroad coal cars because the amounts of coal and the distances over which they are transported by railroad in the United States are so large that the resulting reduction in drag could, potentially, result in an annual saving of millions of gallons of diesel fuel.
Advancing Technologies Harness the Power of Wind, Water, and the SunTBMG-54517/1/2009
Renewable energy will be the world’s fastest-growing source of electricity generation over the next two decades, although it will still make up a relatively minor portion of the global energy supply, according to the Energy Information Administration. The majority of that increase will come from the use of wind power and water power, or hydropower. The Obama Administration advocates a policy that would require 25% of United States electricity demand be met by renewable energy by 2025.
Advancing Technologies Harness the Power of Wind, Water, and the SunTBMG-54647/1/2009
Renewable energy will be the world’s fastest-growing source of electricity generation over the next two decades, although it will still make up a relatively minor portion of the global energy supply, according to the Energy Information Administration. The majority of that increase will come from the use of wind power and water power, or hydropower.
Declarable Substances Recommended PracticeARP9536 (Historical)3/28/2008
This standard applies to the aerospace and defense industries and their supply chain.
E-1 Environmental Committee
SiO2/TiO2 Composite for Removing Hg From Combustion ExhaustTBMG-25541/1/2008
Pellets made of a high-surface-area composite of silica and titania have shown promise as means of removing elemental mercury from flue gases. With further technical development and commercialization, this material could become economically attractive as a more-effective, less-expensive alternative to activated carbons for removing mercury from exhaust streams of coal-burning power plants, which are the sources of more than 90 percent of all anthropogenic airborne mercury.
Making Activated Carbon by Wet Pressurized PyrolysisTBMG-115711/1/2006
A wet pressurized pyrolysis (wet carbonization) process has been invented as a means of producing activated carbon from a wide variety of inedible biomass consisting principally of plant wastes. The principal intended use of this activated carbon is room-temperature adsorption of pollutant gases from cooled incinerator exhaust streams.
Commercialization of Silica-Titania Composites, a NASA Gray Water Post-Processor Technology, for Terrestrial Applications2006-01-20097/17/2006
Silica-titania composites have been engineered and proven to be a plausible post-processor technology for water recovery. The premise behind this technology is the adsorption and subsequent mineralization of organic compounds. Concurrent with this NASA-based research, faculty at the University of Florida have explored the efficacy of this technology for additional applications. Those that have shown the most promise include greater than 98% removal of volatile organic compounds (VOCs) and Hazardous Air Pollutants (HAPs) from pulp and paper mills and greater than 99% removal of mercury from coal-fired power plant flue gas. Both of these industries are facing pressing regulations that may be implemented as early as 2006. As a result of these initial successes, faculty at the University of Florida have initiated a start-up company, Sol-Gel Solutions, LLC to commercialize the silica-titania composite technology for the aforementioned applications and others that are currently being investigated.
Mazyck, David W.
Hydrogen Peroxide Enhances Removal of NOx From Flue GasesTBMG-1671/1/2005
Pilot scale experiments have demonstrated a method of reducing the amounts of oxides of nitrogen (NOx) emitted by industrial boilers and powerplant combustors that involves (1) injection of H2O2 into flue gases and (2) treatment of the flue gases by caustic wet scrubbing like that commonly used to remove SO2 from combustion flue gases. Heretofore, the method most commonly used for removing NOx from flue gases has been selective catalytic reduction (SCR), in which the costs of both installation and operation are very high. After further development, the present method may prove to be an economically attractive alternative to SCR.
Acoustic Navigation Aid for Autonomous MinersTBMG-295058/1/2000
Miners today use externally powered machines designed to be used by a single operator, the autonomous miner. Many companies offer computer-operated mining equipment that can be used for both high wall and underground applications. Programmable logic controls with ring laser gyroscopes and inclinometers are utilized to enable miners to follow prescribed paths in a coal seam with accuracy. Because of this technology, miners may be positioned in nonhazardous locations as they steer the mining equipment.
Effect of Propene on the Remediation of NOx from Engine Exhausts1999-01-368310/25/1999
Plasma treatment of diesel exhausts has been investigated in recent years due to its potential for remediating NOx in emissions. Hydrocarbons in the exhausts have been found to play an important role in the reaction chemistry during remediation. In this paper, we report on a computational study of the plasma treatment of simulated exhausts containing propene to investigate the effects of hydrocarbons on the conversion pathways for NOx.
Dorai, Rajesh, Kushner, Mark J.
NOx Destruction in Air and Nitrogen by Dielectric Barrier Corona Discharge98251010/19/1998
Destruction of NOx (200 ppm - 1%) by dielectric barrier corona discharge in zero air and nitrogen was studied at 298 K and pressure 1 atm. Effects of adding of hexane or ammonia were also evaluated. The kinetics and the products of the destruction were determined as functions of the specific discharge energy, contact time and NOx concentration. Two ranges of the specific energy deposition which reflect the competition between the destruction and production of NOx in discharge were found. At low specific energies (< 500 J/L) an efficient removal of NOx both in air and nitrogen is observed.
Krishtopa, Larisa G., Krasnoperov, Lev N.
Navigation and Control of Continuous Mining SystemsTBMG-322006/1/1998
Research conducted at the Pittsburgh Research Center (formerly U.S. Bureau of Mines) developed technology that will allow computer-assisted operation of mechanized equipment normally used in underground room-and-pillar coal mining, while permitting workers to be located away from the hazardous coal extraction area (the face). Advanced navigation and control technologies developed for underground room-and-pillar and highwall coal mining can be applied to commercially available mining equipment. The technology being developed uses off-the-shelf components, minimizing the effort required to adapt it to mining equipment. Because the new developments are completely modular, only the modules required in a particular application need be used on the system.
Methanol synthesis from CO 2 and H 297846910/27/1997
RITE and three national institutes of Ministry of International Trade and Industry (MITI) have been jointly developing a CO2 mitigation system in “Project of Chemical CO2 Fixation and Utilization Using Catalytic Hydrogenation” since 1990. A conceptual total system of the project is composed of the separation/recovery via membrane separation of a large amounts of CO2 emitted from stationary sources such as power plant, iron-making plants, chemical plans and so on, H2 production by water electrolysis, methanol synthesis from CO2 and H2, and of the transportation of the methanol produced to the sites for energy consumption and/or chemical production. An application of the system to a 1,000 MW coal fired power plant could recover 470 ton/h of CO2 and produce 323 ton/h of methanol. If the methanol produced is used for a power plant in Japan, the energy efficiency and the CO2 reduction rate of the system could be estimated to be around 30%, 36% respectively. RITE and NIRE previously developed Cu/ZnO-based multicomponent catalysts containing two or three metal oxides for methanol synthesis from CO2 and H2 1,2,3). In the present study, our group has examined the long term stability of the catalyst in methanol synthesis. Furthermore, we have investigated the methanol synthesis over the multicomponent catalysts by using a reactor with a recycling equipment for unreacted gases. The present investigations made clear that the catalyst developed are highly active (>600 g-MeOH/kg-cat h) and selective (> 99.9%) and that the purity of the refined methanol is 99.9% or more. The methanol produced has been used tentatively for a methanol fuel test car.
Takeuchi, Masami, Watanabe, Taiki
MHD Repowering of a 250 MWe Unit of the TVA Allen Steam Plant9292868/3/1992
Coal fired MHD repowering is considered for the TVA Allen Steam Plant. The performance of the repowered plant is presented. Cost comparisons are made of the cost of repowering with MHD versus the cost of meeting similar standards by installing scrubbers and selective catalytic NOx reduction (SCNR). For repowering of a single 250 MWe unit, the costs favor scrubbing and SCNR. If one considers a single repowering of all three 250 MWe units by a single MHD topping cycle and boiler, MHD repowering is more economical. Environmental emissions from the repowered plant are estimated.
Chapman, J. N., Attig, R. C.
Combustion of Minimally Processed Coal Liquids in a Diesel Engine9003992/1/1990
A modified CFR Cetane engine was used to analyze combustion characteristics and emissions of minimally processed coal liquids (MPCLs). To aid in combustion of the coal liquids, the ability to heat the fuel and inlet air was added. The MPCLs are derived from atmospheric distillation of coal liquids. The coal liquids are byproducts of coal gasification of Elkhorn bituminous and North Dakota lignite using the atmospheric, air blown Wellman-Galusha and pressurized, oxygen blown Lurgi gasifiers, respectively. The MPCLs were compared with three reference fuels: diesel No. 2, U12 (21 cetane number) and #-methyl napthalene (0 cetane number). The inlet air was heated from 340 to 535 K and the compression ratio was varied from 13 to 31 to provide sufficient range in temperature and pressure necessary for the combustion of low cetane number fuels. At each operating condition, fuel consumption, cylinder pressure, ignition delay, and emisions were measured. By monitoring the exhaust CO2 levels, the overall equivalence ratio was held at 0.60. The engine operated successfully on 100% MPCLs. By comparing to the ignition characteristics of the reference fuels, the cetane number rating on the MPCLs is estimated at about 21. A three dimensional nonlinear regression program was used to fit the parameters of an Arrhenius type equation to the engine's ignition performance. Activation energy was found to correlate with apparent cetane number for the full boiling range fuels. Under similar engine operating conditions, maximum cylinder pressure, maximum rate of heat release, thermal efficiency, and NOx of the MPCLs were similar to those of diesel fuel. Exhaust soot concentrations of MPCLs, however, were substantially higher than levels found burning diesel fuel.
Kittelson, D. B., Brehob, D. D.
Hydroprocessing of Direct Coal Liquefaction Product for Diesel Engine Fuel8921319/1/1989
A contemporary coal liquefaction product from the Wilsonville pilot plant was processed to make two diesel test fuels for engine research. A naphtha fraction was separated by distillation, and the diesel fraction was upgraded by hydrogenation. Processing objective was to make two stable products with acceptable ignition quality. A trial run was made over a range of pressures and residence times to establish minimum severity to meet the objective. About 85 gallons of product was made at minimum severity and 81 gallons at slightly higher severity. The products resembled petroleum diesel fuels except for marginally high viscosity and low accelerated stability. Product characterizations included 30.1 and 35.4 cetane number.
Sefer, Norman R., Erwin, Jimell
Structure of Middle Distillate Fuels: On the Atomic Carbon and Hydrogen to Carbon Ratio at Alpha Position to Aromatic Rings88165410/1/1988
The alkyl, naphthenic, or total carbon atoms of the functional groups at alpha position to aromatic rings and their hydrogen to carbon ratio are some of the important parameters for structural analysis of fossil fuel products. The Brown-Ladner concept for the atomic hydrogen to carbon ratios at alpha, and beta and gamma positions is over twenty-five years old and, in spite of its very approximate nature, is still being used by both Proton and Carbon-13 Nuclear Magnetic Resonance analysts. In this paper, we present a number of novel formula-structure relationships for precise determination of different carbon atom types at alpha position to aromatic rings and the average number of hydrogens per alpha-carbon.
Glavinčevski, Boris, Gülder, Ömer L., Gardner, Leslie
Production Technology in Japan During Ten Years of War (1938 - 45)88160810/1/1988
During the Ten-Year War 1935-1945, the Japanese Navy played a leading role in the R&D and production of domestic aviation fuels and high-grade lubricants, by means of technological imports from abroad (mainly from the U.S.A.) at the beginning and of self-development in the latter part of the period. One of the features is a hydrogenation process, which was started with catalyst development and successfully achieved production in large-scale plants. The efforts also achieved certain self-sufficiency in high-grade lubricants that had been dependent on imports.
Katoh, Fusanosuke
Comparative Economics of Methanol and Gasoline87206111/1/1987
The world has large reserves of crude oil and gas; but they are concentrated mainly in the Middle East. Eventually, economic and political factors will force the U.S. to use new domestic feedstocks for manufacturing liquid motor fuels. Among the possible alternatives are synthesizing methanol from natural gas or coal or making gasoline from coal by direct liquefaction. Methanol synthesized from domestic natural gas in a new, plant at current gas prices using demonstrated technology would cost 30% more than gasoline for equal vehicle miles. However, a program to make large amounts of methanol would likely raise gas prices. The higher feedstock cost would make the methanol even more expensive and possibly cause the methanol industry to move overseas where gas is cheaper. Because the U.S. has large reserves of coal, making methanol from coal is not likely to disturb existing supply arrangements nor raise the cost of coal significantly. However, processing to make methanol from coal is complicated and thermodynamically inefficient, and making methanol from coal would cost almost three times as much as gasoline for equal vehicle miles. Although research on direct coal liquefaction has been modest during recent years, it has yielded major technology improvements. Manufacturing gasoline from coal using demonstrated technology would use available domestic resources effectively and would be much more economical than manufacturing methanol from coal. Nonetheless, gasoline made from coal would be nearly twice as expensive as gasoline made from crude oil at current prices. We believe that government money being made available for promotion of alternative vehicle fuels would be better spent on improving processes for manufacturing alternative fuels--such as coal liquefaction--than on “demonstrating” vehicle performance on methanol-based fuels.
Wagner, T.O., Tatterson, D.F.
Synthetic Gasolines and Diesel Fuels from Processing of Shale Oils and Coal Liquids86154210/1/1986
Seven test fuels were provided to research projects in the Department of Energy Alternative Fuels Utilization Program. Currrent refining technology was applied for conversion of shale- and coal-derived feedstocks to gasolines, diesel fuel, and turbine fuel. Hydrogenation was used in all four processing sequences, supplemented by catalytic reforming, distillation, and blending as needed to meet the product objectives. Major operating conditions are described for each process step. Laboratory analyses are provided for feedstocks, intermediates, and final products.
Sefer, Norman R., Erwin, Jimell
An Overview of the Methods for Structural Analysis: Proton NMR and GC-MS of Middle Distillate Aromatic Fractions85207910/1/1985
An overall comparative view of the analytical methods for hydrocarbon type and structural group (CHn n = 0-3) analysis of middle distillate fuels is presented. The inadequacy of traditional ASTM methods (e.g. n-d-M D3238, FIA D1319, MS D3239 and D2425) associated with the inability to relate the fuel composition to combustion performance has provided an incentive to use alternative techniques. This incentive will increase as conventional crude quality decreases and synthetic crudes become more widely used, HPLC. GC-MS and NMR techniques have emerged not only as essential tools for research but also in routine use for an excellent characterization of fuel composition-ignition quality relationships. The characterization of diesel fuel aromatic fractions by 1H NMR and GC-MS is discussed in detail.
Glavinčevski, Boris, Gardner, Leslie
Single-Cylinder Diesel Engine Study of Several Shale and Coal-Derived Fuels84133310/1/1984
Several synthetic fuels derived from shale and coal were evaluated with respect to a reference petroleum-based Diesel fuel. Tests conducted using a single-cylinder DI Diesel engine were designed to quantitatively compare the fuels on the basis of performance, combustion characteristics, gas-phase emissions, particulate emissions, and biological activity of the solid phase soluble organic fraction. The biological activity was assessed using the Ames Salmonella typhimurium test. The shale fuels studied were a Paraho marine Diesel fuel and a light shale oil condensate from the Logan Wash in situ retorting operation. The coal liquids, Solvent Refined Coal-II and Exxon Donor Solvent, could not be run neat; therefore, they were blended 20% and 40% by volume with the certified DF-2 baseline fuel. Of the synthetic fuels tested, only the Paraho marine Diesel fuel exhibited the qualities of a good finished Diesel fuel.
Trevitz, S. S., Lestz, S. S., Taylor, W. D.
Screening Tests of Coal Pyrolysis Liquids as Diesel Fuel Extenders8410028/1/1984
Raw oils generated by low-temperature coal pyrolysis were chemically characterized and subjected to tests in three diesel engines of different configuration. The coal liquids were tested as blends with conventional No. 2 diesel fuels, the coal liquids being 20-25% by volume. These tests were performed in support of a broader set of studies on the feasibility of using low-temperature pyrolysis to obtain liquid fuel materials from coal that do not require extensive, costly upgrading. Determination of physical and chemical properties of the pyrolysis liquids indicated a higher hydrogen/carbon ratio and lower aromaticity than typical SRC II and EDS middle distillates. Combustion tests were performed in both direct- and indirect-injection engines at three sites. The results were highly variable, the addition of the oil showing no effect on emissions and performance in some cases, reduced emissions on one engine, and increased emissions in other cases. The results are discussed with reference to prior related work.
Lestz, S. S., Trevitz, S. S.
A Review and Comparison of Reciprocating Engine Operation Using Solid Fuels8313629/12/1983
Future fuels for internal-combustion engines will be derived increasingly from solids such as coal. An alternative to processing coal into liquid fuels is the direct use of solid coal by reciprocating, internal -combustion engines. Specific applications which would be especially suitable for solid fueled engines consist of stationary power plants, marine propulsion systems, and railroad locomotives. Agricultural, construction and mining equipment are examples of other possible applications. The objectives of this study were to review past research on the development of solid coal fueled engines and, from this review, to identify major technical problems and current research needs. The objectives also included comparing the energy usage of several fuels. This comparison indicated a possible 25% energy advantage by directly using solid coal fuels as opposed to using synfuels. The literature review indicated that operation of solid reciprocating engine has been attempted for nearly a hundred years. Problems which have been encountered continuously have involved the fuel delivery system, solid-particle combustion, and engine component wear. Recent investigations (1979-1982) using coal/oil, carbon-black/oil, and coal/water slurries in a variety of reciprocating engines have yielded encouraging results. The use of coal/water slurries is an attractive approach to using solid coal in engines, since fuel handling problems are simpler than using dry-powder fuels, and the slurry is petroleum independent.
Caton, J. A., Rosegay, K. H.
The Production of Alternative Fuels8215722/1/1982
Since man first began to use energy intensively, he has been aware of the need for alternative fuels to the ones he depended on. Today, that search is to find an alternative to crude oil based fuels. This paper outlines the available resources of energy other than crude oil, describes the methods of producing these energy resources and discusses how and when some may find increased useage. The paper concludes that for some years to come, we shall continue to depend on crude oil, but that by the beginning of the next century we shall begin to make use of some of the alternatives, particularly coal and uranium.
Jackson, Robert G.
Crude Sources and Refining Trends and Their Impact on Future Jet Fuel Properties81105610/1/1981
Forecasts of heavier, higher sulfur crudes show the need for more hydrotreat-ing for sulfur removal. Increasing demands for middle distillate products will require more conversion of heavy fractions and more hydrogen processing. JP-5 jet fuel, normally a straight run product, is likely to be made by hydrogenation and hydrocracking with resulting changes in properties. Synthetic crudes from oil shale and coal have special processing needs and will introduce other changes in chemical and physical properties. The study identified properties of future JP-5 production for use in an alternate test procedure to qualify new Navy jet fuels.
Sefer, Norman R., Moses, Clifford A.
Experience with the Testing and Application of Fire-Resistant Fluids in the National Coal Board8109629/1/1981
Knight, G. C.
Industrial Fixed-Bed Coal Gasification: An Economic Alternative to Deregulated Natural Gas8109959/1/1981
The role of coal in the United States energy future will definitely increase due to the higher cost of oil and natural gas. This paper reviews the projected role which coal will play in this country within the next twenty years. Specifically, the generation of coal derived industrial fuel gas using fixed bed gasifiers is reviewed. The fixed bed gasifier technology presented includes the single-stage “galusha” gasifier and the two-stage gasifier design offered by Black, Sivalls & Bryson, Incorporated. The paper reviews the use of various U.S. coals in these industrial gasifiers and presents operational data from a variety of coals. The use of coal derived industrial fuel gas by companies within the U.S. is reviewed including the economic criteria which lead to these industries investing in coal gasification systems. Projected fuel costs are presented. These data suggest a cross-over between coal derived IFG and natural gas costs in the 1985 time frame.
Maurer, Rolf E.
Regional Refining Models for Transportation Fuels from Shale Oil and Coal Syncrudes8104422/1/1981
Refinery linear programming models were developed for Rocky Mountain, Mid-Continent, and Great Lakes regions to make future product volumes and qualities that were forecast for 1995. Shale oil and coal oil syncrudes were introduced as part of the raw materials slate. Cases were run to evaluate conventional products, maximum diesel fuel, and broadcut fuel in-all regions. Methanol, ethanol, MTBE, or synthetic naphtha were evaluated at 10 percent each in gasoline blends along with syncrude components. Composition and qualities of the fuels were determined. Effects on raw materials, energy consumption, and investment costs indicate some what more benefits for broadcut fuel than for maximizing diesel fuel. Gasoline supplements also show advantages in raw materials and energy consumption.
Sefer, Norman R.
Methyl Aryl Ethers from Coal Liquids as Gasoline Extenders and Octane Improvers8104432/1/1981
A mixture of methyl aryl ethers derived from the phenols present in direct liquefaction coal liquids shows considerable promise as a gasoline blending agent and octane improver. The mixture of methyl aryl ethers was blended at five volume per cent with a commercial, unleaded gasoline. The properties and performance of the blend in a variety of laboratory and automotive tests is reported. The tests show that the mixture of methyl aryl ethers improves gasoline octane without degrading other gasoline properties.
Singerman, Gary M.
Energy Reduction — Business and Industry Challenge8010149/1/1980
A discussion of energy reduction considerations includes distinguishing between energy resources (potential supplies of energy) and energy stocks (available supplies of energy). The potential of coal, nuclear fusion, and other forms of energy can result in abundant national energy stocks in the future. In many cases, however, today's needs cannot be deferred into tomorrow. With this in mind, it is evident that energy reduction practices are vital on both a long and short term basis to ensure the economic health of America and the world.
Cannon, Francis V., Ungrodt, Richard J.
Alternate Transportation Fuels8008908/1/1980
Oil shale, tar sands, and coal are very plentiful in North America. They are potential sources of transportation fuels to supplement or ultimately replace petroleum until renewable sources of energy can be developed. Synthetic fuels from oil shale, tar sands, and coal will phase into the supplies of transportation fuels during the rest of this century. The emerging nature of the technologies, the magnitude of petroleum use today, and the costs of building commercial plants all limit the rate at which synthetic fuels can be assimilated. One million barrels a day of synthetic fuels production by 1990 is ambitious but achievable if the governmental bodies cooperate in expediting the permitting and resolving the inevitable obstacles. Synthetic fuels can be refined to high quality transportation fuels using modern refining technology, and they can serve as substitutes for crude oil in refineries with modern hydroprocessing capability.
Handel, Gene M., Newhall, Henry K., Reed, Echol M.
Worldwide Energy Situation-Impact on Commercial Vehicles7904812/1/1979
The world consumption rate of oil is increasing so fast that the supply will not keep pace. During 1977, the world energy consumption exceeded 265 quadrillion BTU s--the equivalent of over 130 million barrels of oil per day. By the year 2000, world energy consumption is expected to more than double. Some time between 1980 and the turn of the century, world oil production will stop growing and slowly begin to shrink. The inescapable conclusion is that petroleum will not be able to maintain its share of the rapidly growing demand for energy. Recognizing that there is a close relationship between energy consumption and the performance of national economies, especially in industrialized nations, other fuels will be needed to meet growth demands. The world must shift from a predominantly petroleum-based economy to one which will phase in other energy sources, with increased emphasis on coal and nuclear power. This transition will require some complex decisions. Nations will have to choose more sparingly among alternative uses of the limited supplies of petroleum. One of the uses will be for commercial vehicles. However, the limited supplies and continuing higher prices will necessarily result in more fuel-efficient vehicles, more sophisticated bulk quantity delivery systems, and more consolidated production-delivery-marketing networks.
McReynolds, L. A.
Alternate Fuels and Alternate Prime Movers in Non - Highway Transportation7909572/1/1979
At some point in the future, the transportation system will have to start to use non-petroleum fuels. One area of the transportation system that is critical is the non-highway (marine, railroad, pipeline and aircraft) since it accounts for about 80% of the freight-ton miles moved in the U.S. With the long-life times of the engines used in this area, and the time it takes to introduce a new prime mover or new fuel, it is important to consider the use of alternate fuels now. This paper covers the factors considered in evaluating alternate fuels and prime movers for non-highway transportation and presents a future outlook on possible fuels and prime movers.
Cart, Eldred N., Percival, James
Tunnel Boring a Mine Slope7804812/1/1978
Tunneling with a boring machine has been used extensively in the construction industry but has been virtually ignored by the mining industry. Looking for a faster and more economical way of constructing a mine slope, the Rochester & Pittsburgh Coal Company turned to a tunnel boring machine to replace the former drilling and shooting method. The results of this decision and the construction of two coal mine slopes are discussed in this paper.
Bullers, Walter E.
Underspoil Coal Haulage7804682/1/1978
To evaluate the feasibility of an alternative to the costly construction and reclamation of haulage roads in surface coal mines, the Bureau of Mines contracted with the Dravo Corp., Denver, Colo., to conduct an engineering and economic evaluation of the haulage of coal out of the strip pit via conveyors running in culverts laid under the advancing spoil. The results of this study, which are presented in this paper, discuss the cost savings, plus the more subtle advantages and disadvantages of this novel haulage system in a number of alternative strip coal mine designs. The Bureau's plans for a demonstration of a prototype underspoil coal haulage system are also outlined.
Johnson, Guy A.
Alternate Fuels for Power Generation7706722/1/1977
The potential for electric utility utilization in an environmentally acceptable manner of various fossil fuels is discussed. Fuels and fuel processes considered include Alaskan oil with either desulfurization of the fuel, or stack gas treatment of the combustion products, shale oil, and coal and coal derived synthetic fuels. The latter category includes solvent refined coal, low and medium Btu gas. methanol from coal as well as “true” liquid fuel from coal and the direct utilization of coal either with stack gas scrubbing and a conventional boiler, or in a fluidized bed boiler.
Weir, Alexander
Another Look at Alternative Fuel Options7707592/1/1977
Alternatives to petroleum-derived transportation fuels can be produced from oil shale, coal, and from a variety of carbonaceous materials including both cultivated biomass and waste materials. In the long-term, hydrogen, often mentioned as an alternative fuel, may be used as an energy carrier or transfer agent; it should not, however, be considered as an energy resource. Among the alternatives, coal-derived or shale-derived fuels could become significant in the national supply within the century. The other alternatives are long-term (post-2000), or, at least without extensive resource development, they are resource-limited. Any identifiable shale-derived fuel probably will appear as conventional finished fuel--either gasoline or distillate. More likely, however, the shale-derived component of fuels will not be identifiable because any shale oil available for the manufacture of transportation fuels within the foreseeable future will be blended with natural crude and used as refinery feedstock. Coal-derived fuels may be methanol, gasoline from methanol, or conventional gasolines or distillate-type fuels either synthesized from coal or refined from coal syncrude, i.e., a “liquefied” coal. Methanol or a methanol derivative would be produced using coal gasification as the primary conversion process. The technology for coal gasification is well established whereas that for coal liquefaction is not fully developed. For this reason methanol or methanol-derived gasoline are the alternative fuels most likely of production if non-petroleum fuels were to be required in the immediate future. The next most likely would be conventional fuels from coal synthesis by the SASOL process. The evidence available to date indicates that should gasoline or distillate be made from either coal or shale oil those fuels will not differ markedly from traditional fuels.
Hurn, R. W.
The Manufacture of Hydrogen From Coal7510952/1/1975
As part of a study for the conversion of coal to fluid fuels, we have developed three process designs for the conversion of Montana subbituminous coal to hydrogen based on three different gasifier technologies. 1. Koppers-Totzek suspension gasification 2. U-GAS™ fluidized-bed gasification 3. Fluidized Steam-Iron Process For comparison with methane from coal, a fourth design, based on the HYGAS® Process has been prepared. Nominal plant capacities are 250 billion Btu/day of product gas. Overall plant efficiencies for conversion of coal to major gaseous products plus by-products are: Product liquefaction requirements are presented. Capital and operating costs (mid-1974) are presented for U-GAS and HYGAS. With coal at $0.30/million Btu, prices for hydrogen and methane are $2.17 and $1.77/million Btu. Methane is more attractive in both efficiency and cost.
Tsaros, C. L., Arora, J. L., Burnham, K. B.
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