Quality lignites

Laboratory experiments have been conducted with a chromium lignite-chromium lignosulfonate mud system both without and with solid lubricants. These studies include filtration loss, cake quality, and their impact on the formation. A comparative evaluation has led to the conclusion that Gilsonite is a better additive compared with sulfonated asphalt as it results in less filtration... 

In absolute terms, the quantities of reactor solids found in various processes do vary considerably. The rate of accumulation is related to several factors, such as coal characteristics, recycle solvent quality and reactor design. However, it can be stated in general terms that liquefaction of low rank coals (sub-bituminous C and lignites) does result in higher rates of accumulation of solids than do similar operations with bituminous coals. For example, during normal operations of the SRC-I pilot plant at Wilsonville, Ala., it has been found that the amount of solids retained varies from about 0.2-0.5 wt.% (moisture-free) for bituminous coals to 1.0-1.9 wt.% (moisture free) for a subbituminous C coal (Wyodak) (72). Exxon also reports much larger accumulations for lignites and subbituminous coals than those found for bituminous coals (73). 

Bouska, V. and PeSek, J. (1999) Quality parameters of lignite of the North Bohemian Basin in the Czech Republic in comparison with the world average lignite. International Journal of Coal Geology, 40(2-3), 211-35. 

Crowley, S.S., Warwick, P.D., SanFilipo, J.R. et al. (1998) Quality of lignites in three areas of the Gulf Coast province. Abstracts with Programs. The Geological Society of America, 30(7), 175. 

Bituminous coal baked in an oven yields a solid carbonaceous material called coke, which is used as a reducing agent in the smelting of iron. Jet is a term applied to high-quality specimens of lignite that have been used to make decorative objects and jewelry. Jet and peat, which is compressed, partially decayed plant matter, will be discussed in Chapter 4 Plants. Cannel coal is another term for hard, compact lignite. This name has been applied to material from Whitby, where most commercial jet comes from, and from Scotland. Objects made of this material date back at least to the Bronze age in Britain (2100-1700 BC). 

Jet is the common name given to black, high-quality, homogeneous specimens of lignite coal. Fossilized plant material, coal consists of a complex mixture of hydrocarbon compounds, water, and small amounts of other elements, usually sulfur. It is very soft and has a very low density. As it is coal, it is also flammable. 

Mei, J. S, Grimm, U. Halow, J. S. "Fluidized-Bed Combustion Test of Low Quality Fuels - Texas Lignite and Lignite Refuse" MERC/RI-78/3, 1978. 

As can be seen from the curve for PSOC coal 93 in Figure 2, the scattering data from lignites can also be fitted quite well with Equation (3) The quality of the fits of the two equations is nearly the same The fact that both equations can be employed in the fits is a result, we believe, of the fact that both Equations (3) and (6) correspond in this case to similar pore-dimension distributions ... 

The objectives of this work were (a) to investigate the operation of an industrial scale boiler during co-combustion of waste wood and lignite of low quality, (b) to determine the CO, SO2, NO, PCDD/F and heavy metal emissions, (c) to compare them with emissions from co-combustion with uncontaminated wood, and (d) to correlate gas emissions with the fuel blend properties. 

Steel Authority India Ltd. (SAIL) has been producing approximately 100-125 tpa mixed cresols in their coke oven plant at Rourkela, Orissa State. Similarly, Dankuni Coal Complex (near Calcutta) of Coal India Ltd. (CIL) have been producing mixed cresols and xylenols to the tune of 200 tpa. Quality of cresols produced by SAIL and CIL is more or less similar to that produced by Neyvelli Lignite. 

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