Fixed bed testing of durable, steam resistant zinc oxide containing sorbents

摘要

The US Department of Energy is currently developing Integrated Gasification combined Cycle (IGCC) systems for electrical power generation. It has been predicted that IGCC plants with hot gas cleanup will be superior to conventional pulverized coal-fired power plants in overall plant efficiency and environmental performance. Development of a suitable regenerable sorbent is a major barrier issue in the hot gas cleanup program for IGCC systems. This has been a challenging problem during the last 20 years, since many of the sorbents developed in the program could not retain their reactivity and physical integrity during repeated cycles of sulfidation and regeneration reactions. Two promising sorbents and (METC6), which were capable of sustaining their reactivity and physical integrity during repeated sulfidation/regeneration cycles, have been developed at the Morgantown Energy Technology Center (METC) during the past year. These sorbents were tested (sulfided) both in low-pressure (260 kPa/37.7 psia) and high-pressure (1034 kPa/150 psia) fixed-bed reactors at 538(degrees)C (1000(degrees)F) with simulated KRW coal gas. High-pressure testing was continued for 20 cycles with steam regeneration. There were no appreciable changes in sulfidation capacity of the sorbents during the 20-cycle testing. The crush strength of the sorbent actually improved after 20 cycles and there were no indications of spalling or any other physical deterioration of the sorbents. In testing to date, these sorbents exhibit better overall sulfur capture performance than the conventional sorbents.