Hot low Btu producer gas desulfurization in fixed bed of iron oxide-fly ash. Annual report No. 1, July 1, 1975--June 30, 1976

Abstract

This is the annual progress report of the APCI support program to assist ERDA in the development of their hot producer gas desulfurization process. An iron oxide-fly ash sorbent will be used in a fixed-bed cyclic operation. Specific objectives of APCI support are sorbent development, definition of process scale-up criteria, and commercial process design. Major emphasis this period has been in the following areas: 1. Development of a Suitable Commercial Sorbent. Twenty different experimental sorbents were prepared. These sorbents were tested in the laboratory-scale ERDA sorber to determine which sorbent can desulfurize the greatest amount of producer gas prior to 10 percent breakthrough. The optimum sorbent using this criteria contains 42 percent iron oxide on fly ash at 20 psig and more than 60 percent iron oxide on fly ash at 400 psig. The effect of iron oxide source, iron oxide content, sorbent support, and sorbent binder on sorbent performance were investigated. 2. Definition of Process Scale-Up Criteria. An isothermal sorption model was developed that correlates sorbent performance at 10 percent breakthrough with good accuracy for ranges of process variables. The sorption model was derived from experimental dynamic data using U.S. Steel iron oxide source on fly ash with bentonite binder.