摘要 |
Disclosed is a method and apparatus for producing synthetic gas by using a blast furnace as a gasifier. The furnace is charged in a conventional manner with particles of solid carbonaceous material such as normal, low grade or undersized coke together with slag-producing material, such as limestone, silica and/or basic oxygen furnace and/or open hearth furnace slag. Fluent fuel such as pulverized coal mixed with oxygen-containing gas and with lime if desired is injected into pre-ignition chambers near the hearth line of the furnace. The fluent fuel is ignited and partially gasified in the pre-ignition chambers, creating a hot reducing gas that enters the furnace raceway and passes upwardly into and through the body of charge material in the furnace stack. At the resulting high temperatures ash from the fluent fuel liguifies within the system to provide a liquid slag. Under a controlled high temperature reducing atmosphere, the liquid lime removes essentially all sulfur from the product gas. To reduce the high gas temperature, steam is injected above the pre-ignition chambers. The steam reacts with the hot solid carbonaceous material in the stack to disassociate and enrich the product gas with additional hydrogen and carbon monoxide. Liquid carbonaceous material such as oil, tar, or the like is injected into the furnace stack above the location at which steam is injected and is cracked by the sensible heat of the gas passing through the body of charge material in the furnace, thus further cooling the gas and enriching its calorific value.
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