Liquid fuels coal-derived

Reforming for producing hydrogen from high hydrogen-content, coal-derived liquid fuels. 

Alternative Fuel Includes methanol, denatured ethanol and other alcohols, separately or in mixtures of 85% by volume or more with gasoline or other fuels, CNG, LNG, LPG, hydrogen, coal derived liquid fuels, fuels other than alcohols derived from biological materials, electricity, neat biodiesel, or any other fuel determined to be substantially not petroleum and yielding substantial energy security benefits and substantial environmental benefits. It is defined pursuant to the EPACT (Energy Policy Act of 1992), alternative fuels. 

Emissions Sampling of Combustion Effluents from a Stationary Diesel Engine That Bums a Coal-Derived Liquid Fuel... 

Tabi, R. and Mesko, J. E., "Combined Gas-Steam Turbine Cycle Using Coal-Derived Liquid Fuel - A Viable Alternative to Direct Combustion of Coal," Proc. 2nd Intern. Conf. 

Muzio, L. J. and Arand, J. K., "Combustion and Emission Characteristics of Coal-Derived Liquid Fuels," EPRI Report AP-1878, 1981. 

Grumer, J., Cohn, A., and Stein, T. R., "Combustion of Coal Derived Liquid Fuels," Paper Presented to Symposium On New Fuels and Advances in Combustion Technologies sponsored by Institute of Gas Technology, 1979. 

Sharypov V.I., Kuznetsov B.N., Beregovtsova N.G., Reshetnikov O.L., Baryshnikov S.V. (1996) Modification of iron ore catalysts for lignite hydrogenation and hydrocracking of coal-derived liquids. Fuel, 75, No 1, 39-42. 

Herod, A.A., Lazaro, M.-J., Domin, M., Islas, C.A., Kandiyoti, R. (2000) Molecular mass distributions and structural characterisation of coal derived liquids. Fuel, 79, 323-337. 

The majority of today s turbines arc fueled wth natural gas or No. 2 distillate oil. Recently there has been increased interest in the burning of nonstandard liquid fuel oils or applications where fuel treatment is desirable. Gas turbines have been engineered to accommodate a wide spectrum of fuels. Over the years, units have been equipped to burn liquid fuels, including naphtha various grades of distillate, crude oils, and residual oils and blended, coal-derived liquids. Many of these nonstandard fuels require special provisions. For example, light fuels like naphtha require modifications Co the fuel handling system to address high volatility and poor lubricity properties. 

The transportation fuels produced and marketed (Table 18.9)40 met the South African fuel specifications of that time and included some coal-derived liquids (not shown in Figure 18.5). Although the refinery originally produced no jet fuel, it was demonstrated that the hydrogenated kerosene range oligomers from olefin oligomerization over a solid phosphoric acid catalyst met the requirements for jet fuel.38 (Semisynthetic jet fuel was approved in 1999 and fully synthetic jet fuel was approved in 2008 DEFSTAN 91-91/Issue 6). 

Figure 4.2 presents a simplified flow diagram of the ENCOAL Liquid from Coal (LFC) process. The process upgrades low-rank coals to two fuels, Process-Derived Coal (PDF ) and Coal-Derived Liquid (CDL ). Coal is first crushed and screened to about 50 mm by 3 mm and conveyed to a rotary grate dryer, where it is heated and dried by a hot gas stream under controlled conditions. The gas temperature and solids residence time are controlled so that the moisture content of the coal is reduced but pyrolysis reactions are not initiated. Under the drier operating conditions most of the coal moisture content is released however, releases of methane, carbon dioxide, and monoxide are minimal. The dried coal is then transferred to a pyrolysis reactor, where hot recycled gas heats the coal to about 540°C. The solids residence time... 

Proof of the existence of benzene in the light oil derived from coal tar (8) first established coal tar and coal as chemical raw materials (see Feedstocks, coal chemicals). Soon thereafter the separation of coal-tar light oil into substantially pure fractions produced a number of the aromatic components now known to be present in significant quantities in petroleum-derived liquid fuels. Indeed, these separation procedures were for the recovery of benzene—toluene—xylene (BTX) and related substances, ie, benzol or motor benzol, from coke-oven operations (8) (see BTX PROCESSING). 

Thomas, K.P., and Hunter, D.E. 1989. The Evaluation of a Coal-Derived Liquid as a Feedstock for the Production of High-Density Aviation Turbine Fuel. DOE Report DOE/MC/11076-2993. United States Department of Energy, Washington, DC. 

Describing the behavior of undefined mixtures, whether from natural or synthetic sources, often begins with the separation of these complex systems into effective pseudocomponents by distillation (1 ). Each pseudocomponent is then characterized as if it were a pure compound, and its characterization data are used in appropriate correlations. The presence of nonvolatile residuum poses a serious limitation to such methodology. For coal-derived liquids, heavy crude oils, tar sands, and shale oil, more than 50 percent of the fluid may not be distillable (JL). Since this nonvolatile residue cannot be separated using conventional techniques, new methods of separation and characterization must be developed to provide the necessary information for design and operation of plants utilizing the fossil fuels mentioned above (2). 

Evaluation of Coal-Derived Liquids as Utility Boiler Fuels... 

The synthetic fuels evaluation at Mississippi Power Company s Plant Sweatt 1s just one of a number of tests, sponsored by the Electric Power Research Institute (EPRI) under project RP 2112, to assess the potential of coal derived, liquid synthetic fuels as an alternative or substitute for liquid petroleum fuels. 

EPRI also contributed 27,700 barrels of synthetic fuel to the test effort. Due to funding constraints, the intensive testing of the coal derived liquids could not be maintained for the entire project. Therefore, the first phase of the testing on three of the fuels was considered the "Intensive Test Matrix", while the last three coal derived liquids were examined under normal plant operation and are referred to as the "Longevity Tests". 

Demonstrate the use of coal derived liquids as potential substitutes for petroleum fuel oil in a full scale, wall fired utility boiler. 

Nitrogen oxide emissions (quantitatively expressed as nitrogen oxide, NO) from unoptimized coal derived liquid combustion were higher than that of No. 6 fuel oil or natural gas (Figure 3). 

This was anticipated since the relative nitrogen content of the coal derived liquids 1s higher than either baseline fuel (0.44% versus 0.29% typically). However, the combination of burners out of service and low excess air reduced N0X emissions from the coal derived liquid as much as 50% in some cases (Figures 4 and 5). Table II lists some typical N0X reduction results for the Intensive test matrix. 

Blmodal size distributions of the H-Coals showed little change at reduce air conditions. Emissions of S0a from the coal derived liquids were also quite low (with correspondingly low acid dewpoints) as these chemically cleaned fuels contained only a fraction of the sulfur normally found 1n petroleum liquids (0.15% versus 2.29% typically). 

Overall, the consensus of the participants 1s that any of the six coal derived liquids could be considered as an acceptable replacement for liquid petroleum fuel 1n either Plant Sweatt boiler with no equipment modifications, equipment additions or environmental variances. The application or replacement usage of these coal derived liquids 1n other utility boilers would not seem to be any more difficult but should be prefaced by an extensive, Individual site assessment of candidate units. The few modifications required at Plant Sweatt Indicate that a limited number of design criteria would be affected 1f these six synthetic liquids were to be Included 1n the fuel specifications of future utility boilers. The handling and emission characteristics of coal derived liquids may even be preferable to certain petroleum liquids 1n some utility applications. 

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