Coal-oil mixtures

Includes light oil, methane, coal—oil mixture, propane gas, blast furnace gas, wood, and refuse. 

Coal, energy Coal-oil mixtures Coal-water slurry Gas turbine coal fuel Diesel coal fuel Fuel heneficiation, desulfurization... 

We will be managing the 20 MW MHD combustor competitive prototype projects that are currently under way. One of these three contractors will be selected to develop and produce the combustor for a 50 MW MHD component development and integration facility scheduled for operation in Montana in FY 82. We will also be managing two coal/oil mixture demonstration projects. One will involve a utility steam generator and one is a blast-furnace operation. 

MHD Coal/oil mixture (COM) Industrial heat/steam Pulverized Fluidized-bed Stoker COM Domestic/commercial Combustion energy capture by magnetic fields Burning coal/oil mixtures in oil furnaces Industrial plant power Hand-stoked space heating 8-11 1 Laboratory Demonstration Small Pilot Common Demonstration 800-4000 1-100 1-100 1-100 1-100 0.005-0.05 Same as above Noncaking 3-10 cm... 

The use of coal slurries, either coal-oil mixtures (COM) or coal-water mixtures (CWM), has been the subject of considerable research because of the potential to replace fuel oil in boilers. Recent work has shifted in favor of CWM over COM, as the cost savings for the latter were not enough to offset conversion costs. CWM is typically composed of 60-75 percent coal, 24-39 percent water, and 1 percent chemical additives. The advantages of CWM compared with dry pulverized fuel are the ease and safety of handling,... 

The adsorption of surfactants in fuel oil onto pulverized coal has been studied in connection with the development of coal-oil mixtures (COM), i.e., stable dispersions of finely pulverized coal in fuel oil. The stabilization of such dispersions by a cationic surfactant has been shown (Kosman, 1982) to involve adsorption of the cationic via its postively charged head group onto nucleophilic sites on the coal, with its hydrocarbon group oriented toward the oil phase. The adsorption of alkylaromatics on carbon black from w-heptane indicates adsorption in an orientation parallel to the interface, with the alkyl chains remaining mobile on the surface (van der Waarden, 1951). Increased length of the alkyl chains increases the degree of dispersion of the carbon. 

Methods for burning mixtures of pulverized coal in oil (variously called colloidal fuel, coal-in-oil slurry, or coal-oil suspension) have been studied for nearly a century and require the production of coal-in-oil suspensions. Stable short-term suspensions of coal in residual fuel oil are easily attained if the coal is pulverized to 200 mesh (75 am) and, by adding surfactants, long-term stability can be obtained so that the coal will not settle out of the mixture even over periods as long as a few months. The interaction between the coal and the hydrocarbon allows the apparent viscosity of the coal-oil mixture (COM) to be 10 times greater than the fuel oil base and special precautions may be taken to provide adequate pump capacity, heating systems for the slurry, and properly sized burner nozzles. 

Properties of Bituminous Coals Suitable for Use in Coal-Oil Mixtures... 

For heterogeneous fuels such as coal-oil mixtures, control of the oil s potential for coating the coal particles requires treatment of its interaction energy [1.21]. 

J.C. Blake, A.J. Sabadell (eds.) Proceedings of the First International Symposium on Coal-Oil Mixture Combustion (Mitre Corporation, Mi trek Division, McLean, Va. 1978)... 

During the heating of the coal-oil mixture, decomposition of the coal occurs, as evidenced by an increase in the proportion of quinoline-insoluble material. 

Coal Oil Mixture (COM) Pulverized coal can be mixed with oil and kept in suspension by agitation, recirculation, or by use of additives. Transportation by pipeline is possible, but truck, train, or barge shipment may be more economical. COM is burned with equipment similar to that used for oil firing. 

FIGURE 11-4 Viscosity as a function of temperature for coal-oil mixture. (From Kreusing and Franke, 1979. Reprinted with permission of BHR Group.)... 

Kreusing, H., and F. H. Franke. 1979. Investigations on the Flow and Pumping Behavior of Coal-Oil Mixtures with Particular Reference to the Injection of Coal-Oil Slurry in the Blast Furnace. Working paper C-2, BHRA Group, Hydrotransport 6, BHRA. 

Adams-Viola, M., Botsaris, G.D., Filymer, W.G., Jr., Glazman, Yu.M. and King, K.D. (1982) The effect of coal particle aggregation on the sedimentation and rheology of coal-oil mixtures. Colloids Surfaces, 4,255-69. 

CWS technology has been under development for well over a century, with the blending of pulverized coal with both water and oil. The first patents for coal-oil mixtures (COM) were issued to Smith and Munsell in 1879, as a means for extending the oil resource and reducing the costs of liquid fuels [11]. Relatively low costs of crude oil over time, however, suppressed interest in this technology. COM interest again arose in the 1970 s due to the oil price shocks, and several types of slurry fuels were developed including COM, with <10 percent water in the fuel slurry, coal-oil-water (COW) suspensions of coal in fuel oil and >10 percent water, coal-methanol fuel (CMS) where fine coal particles are slurried in methanol, and various CWS formulations [11]. 

Coal/oil mixture Burning coal/oil mixtures Demonstration ... 

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