Characterization and optimization of sorbents utilized for emission control during coal gasification. 1997 Fourth quarter research report, October 1, 1997--December 31, 1997

Advanced integrated gasification combined cycle and pressurized fluidized bed combustion power system requires both hot gas desulfurization and particulate filtration to improve system thermal efficiency and overall performance. Few metal oxides were evaluated to be the sorbent candidate for hot gas desulfurization process. The use of waste iron oxide as a disposable metal oxide sorbent will alleviate the constraints imposed on iron oxides including the degradation of sulfur capacity and its physical attrition required for a regenerable sorbent. The very low cost of waste iron oxides and the elimination of the investment associated with sorbent regeneration make it attractive to replace currently developed sorbent candidates. However, the use of waste iron oxides indicates a significant increase of dust loading for particulate filtration. The slower the reaction rate the iron oxide and coal ash mixture is, the longer residence time and higher iron oxide to coal ratio are required. One of the key issue of the use of waste iron oxides as a disposable sorbent material relies on the capability of particulate filtration efficiency. The current back pulse cleaning of the dust cake had been evaluated; and the preliminary test results indicated that the simultaneous operation of hot gas desulfurization and particulate filtration is feasible. A parametric testing will be performed on hot gas desulfurization and particulate independently first. The independent test results will help optimize the test design and evaluation of the integration of hot gas desulfurization testing and particulate filtration testing to be completed in the first two quarters 1998