METHOD OF PROCESSING SOLID CARBON-CONTAINING FUEL Russian patent published in 1998 - IPC

FIELD: solid fuels technology. SUBSTANCE: method includes thermal purification of initial fuel to remove sulfur and nitrogen compounds by way of feeding oxygen and combustible gas from the furnace gas-assisted fuel gasification stage in amounts ensuring full sulfur and nitrogen oxidation and stabilization of desired temperature purification conditions. Effluent gas from the thermal purification stage is withdrawn to be further processed into sulfuric and nitric acids. Purified fuel is divided into three streams: x, y, and z. The x stream is directed into gasification stage, wherein furnace gas (α) from fuel-combustion stage as gasification agent and oxygen as temperature stabilizing agent are used. The y stream is directed into combustion stage, wherein oxygen as oxidant is used, and z stream is additionally introduced into steam-oxygen gasification stage. Ratio of heat amounts produced in different stages is controlled by distributing fuel between processing stage and furnace gas withdrawal stage in accordance with following formulas: x=α Ky and z=1-(1+α K)y where K=(4q1+3q2)/3q2 is constant, q1 and q2 are heat effects of carbon dioxide conversion and carbon-to-carbon monoxide oxidation, respectively, kJ/mol, provided that 0 < y < 1/(1+α•K) and 0 < α ≤ 1.. Fuel gasification stages are performed while observing specified fuel and oxygen feed conditions with regard to unit weight of furnace gas being processed and weight ratio of steam, oxygen, and fuel in the stem-oxygen gasification stage. Combustion of fuel residues in gasification stage and processing of effluent gases in thermal purification stage are preferably accomplished by contact-nitrose technique. EFFECT: improved method allows not only producing heat but also chemical products: combustible gas, synthesis gas, effluent gases appropriate to produce sulfuric and nitric acids. 5 cl, 1 dwg, 4 tbl