| 摘要 |
<p>804,432. Complete gasefication. WOODALLDUCKHAM CONSTRUCTION CO. Ltd. Nov. 3, 1955 [Nov. 3, 1954; Oct. 19, 1955], Nos. 31853/54 and 29887/55. Classes 55 (1) and 55 (2). In a cyclically operated complete gasefication process the calorific value of the coal water gas is increased to between 450-500 B.Th.U.'s by use of heavy oil and the potential heat of the blow gases of the process is used for preheating primary air for the blow periods, this primary air being also used to burn off carbon deposited from the heavy oil. The coals employed are weakly and non-swelling coals and the heavy oil may be used to carburet the coal water gas and/or it may be vaporized and the vapour passed through the gasefication zone during a run period. In the arrangement shown in Figs. 1a 1b, 1c and 1d the apparatus comprises a generator 1 having a distillation zone 3 and a gasefication zone 2 and two regenerators 4 and 5. The regenerators 4 and 5 have respectively two chequer-filled sections 6, 7 and 8, 9 separated by a carburetter 10 and 11 preferably chequerfilled. The generator is charged with weakly swelling coal and the distillation zone is preferably sub-divided into a number of sections. In the first stage of a cycle comprising a blow period lasting about 1 minute, primary air (Fig. 1a) is introduced into the section 9 of the regenerator 5 and burns off any carbon in the carburetter 11 before passing into the generator 1 preheated to about 700‹ C. The temperature of the air passing into the generator 1 may be controlled by adding cool air to the air preheated in the regenerator 5. Blow gases are led off at the top of the gasefication zone 2 and introduced together with preheated secondary air into the section 7 of the regenerator 4, waste gases leave section 6 and pass to a wasteheat boiler. In the second stage and a run period steam is introduced into section 6 (Fig. 16) and is superheated to about 700‹ C. before entering the generator 1, coal water gas is withdrawn from the top of the distillation zone 3 and passes first through section 8 of the regenerator 5, then through the carburetter 11 into which heavy oil is introduced and section 9 to air outlet 13. In the third stage comprising a second blow period, primary air is introduced into section 6 (Fig. 1c) of the regenerator 4 and waste gases are withdrawn from the top of section 9 of the regenerator 5 and pass to a waste heat boiler. In the fourth stage and second run period steam is introduced into section 9 of the regenerator 5 and carburetted coal water gas is withdrawn at an outlet 12 at the top of section 6 of the regenerator 4. In a modification during each run period steam is passed downwardly through the gasefication zone 2 for a portion of the run. In this modification and in the first embodiment heavy oil may be introduced during pass periods into the carburetter traversed by the super-heated steam so that a mixture of super-heated steam and vaporized oil enters the generator 1. In still further modifications sections 7 and 8 of the regenerators 4 and 5 may be omitted and all the heavy oil may be vaporized and admitted into the generator with the super-heated steam.</p> |
