Seeded coal process

The basic seed processing plant design is based on 70% removal of the sulfur contained in the coal used (Montana Rosebud), which satisfies NSPS requirements. Virtually complete sulfur removal appears to be feasible and can be considered as a design alternative to minimize potential corrosion problems related to sulfur in the gas. The estimated reduction in plant performance for complete removal is on the order of 1/4 percentage point. The size of the seed processing plant would have to be increased by roughly 40% but the corresponding additional cost appears tolerable. The constmction time for the 500 MW plant is estimated to be ca five years. 

MHD programs in the United States are concentrated in two major facilities. A Component Development and Integration Facility is located in Butte, Montana, and a Coal Fired Flow Facility at the University of Tennessee to studies coal fired MHD, slag processing, seed handling and downstream systems. 

Supercritical extraction has been used increasingly in recent years for specialized processes. These processes include separation of drugs from plants, oils from vegetable seeds, impurities from labile materials, and chemical feedstocks from coal and petroleum residual. The utility of supercritical extraction processes stems principally from the enhanced solubility characteristics of CO2 near its critical point and the ease with which the solvent can be recovered for recycle. 

Wood ashes.—The ash of wood, not coal, contains about 30 per cent, of potassium carbonate. Prior to the exploitation of the Stassfurt salts about the middle of the nineteenth century, the chief source of potash was wood ashes, and the process is still used in certain localities where wood-fuel is employed and where much waste wood is available—e.g. in some parts of Canada, United States, Russia, Spain, etc. The ash of trees, hedge-cuttings, sawdust, etc., can be made to yield potash.5 In the Caucasus, the sunflower is grown on waste land for the sake of its seed. The stalks, leaves, etc., are a by-product and are burnt the ash is used as a source of potash. Nearly 7000 tons per annum of crude potash from this source were exported from Novorossik in Russia. The residues in the manufacture of olive oil and almond shells are also stated by G. l Abate to be exceptionally rich in potash salts F. W. F. Day claims that the roots of the water hyacinth (eiehornia crassipes) have... 

The total U.S. annual anthropogenic release of silver to the atmosphere from production processes and consumptive uses in 1978 was estimated at 77,700 kg (Scow et al. 1981). Of this amount, an estimated 30,000 kg were released from metals production, 22.000 kg from use in electrical contacts and conductors, 9,000 kg from coal and petroleum combustion, 7,000 kg from iron and steel production, 2,000 kg from cement manufacture, and the remainder from miscellaneous uses. Urban refuse was the source of an additional 10,000 kg. Smith and Carson (1977) estimated that cloud seeding with silver iodide contributed 3,100 kg annually (based on data from the early 1970s). 

Extract production, if valuable substances are separated from a raw product and the feed carrier is a valueless raffinate phase (for example, hop and spices extraction, oil seed extraction, valuable substance extraction from coal or from residues of carbon processing)... 

The rice husk-based bioelectricity hfe cycle starts with the production of agricultural inputs such as rice seed, fertihzer, and pesticide, which then are used for rice farming. After the rough rice grains are harvested, rice husk is separated from brown rice [44]. While the brown rice is normally processed to obtain white rice for commercial purpose, the rice husk is directly transported to the power plant for generating electricity. The operation of rice husk-based power plants is similar to that of coal-based power plants. Nevertheless, as rice husk tends to contain less sulfur than coal, limestone consumption is omitted when considering the rice residue-based power plant. 

Carbonization and activation of coal resources for modem usage complete the process of coalification initiated anything from 300 X 10 to 15 X 10 years ago. It is somewhat unfortunate that the scientific worlds of coal and activated carbon have developed rather independently of each other. They have so much in common, both starting from the organic materials which constitute wood, grass, seeds, etc. Resultant coals, from an adsorption point of view, are not straightforward materials to study and exhibit many of the deep-seated problems which beset the adsorption chemists of today who work with microporous-activated carbon. 

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