FLUID BED DESULFURIZATION

摘要

A method and apparatus for desulfurizing a gas and regenerating a sorbent is disclosed. The sulfurcontaining feed gas which can be an effluent gas from a coal gasification reactor, for example, is desulfurized with a particulated metallic oxide sorbent in a transport riser. The sulfided sorbent is than separated from a desulfurized effluent gas and regenerated by contact with an oxygen-containing gas in a transport riser. The regenerated sorbent is separated from an SO2 containing offgas and recycled to the desulfurization step. The degree of sorbent conversion in the desulfurization step is held at a low level and the sorbent regeneration rate is increased to avoid excessive temperature rise in the regeneration step . In such manner, sorbent cooling can be substantially eliminated. The regeneration riser preferably comprises a once-through lift riser to minimize the riser transport gas requirements to just oxidant gas or oxidant gas mixed with a reduced amount of diluent gas. A reduction in use of diluent gas give a relatively high offgas SO2 concentration of as much as 15 mole percent, suitable for sulfuric acid manufacture and/or reduction to sulfur.