| 摘要 |
<p>644,004. Gasifying carbonaceous materials. IMPERIAL CHEMICAL INDUSTRIES, Ltd. February 28, 1947, No. 5800. [Classes 55(i) and 55(ii)] Water gas or coal gas is produced by passing steam through particulate carbonaceous material as a fluid bed at high temperature, the material then passing to a thermal treatment step in which it is fluidized by a convenient gas and atomized or vaporized oil, the gaseous or vaporous hydrocarbons produced being added to the water gas or coal gas to give a carburetted gas. Particulate coal is maintained as a fluid bed in a carbonization vessel 2 by superheated steam introduced through a pipe 4. The material at about 800‹C descends to a cracking vessel 7 in which it forms a fluid bed by passage through it of a steam and atomized oil mixture. The water gas, coal gas and hydrocarbons from both vessels after removal of steam constitutes a gas equivalent to town's gas. The material is conveyed by preheated inert gas, e.g. nitrogen into a combustion vessel 12 and maintained as a fluid bed by combustion air supplied through pipe 14 passing over a weir 17 having reached a temperature of about 1100‹C and descending through a pipe 18 into the carbonization vessel. A controlled portion is caused to mingle with fresh coal fed through a pipe 1. In an example employing smallscale apparatus, a gas mixture from the carbonization vessel comprised H2 56, CO 20.6, CO2 12.2, CH4 8.2, C2H2n 1.9, O2 0.1 per cent. Oil gas from the cracking vessel comprised CH4 50, CnH2n 42, C2H6 8 per cent and the mixed gases from both vessels after condensation of steam comprised H2 46.6, CO 17.2, CH4 15.1, C02 10.2, CnH2n 7.9, N, 1.6, C2H6 1.3, 02 0.1 per cent. Carbonized material from a separate carbonizing stage in which a fluid bed of coal is maintained by carbonization gases from a prevous operation with or without steam may be gasified in a further stage to which they are fed at a temperature sufficient for the production of carburetted gas.</p> |
