Bench-Scale Development of Fluidized-Bed Spray-Dried Sorbents

摘要

Successful development of regenerable mixed-metal oxide sorbents for removal of reduced sulfur species (such as H(sub 2)S and COS) from coal-derived fuel gas streams at high=temperature, high-pressure (HTHP) conditions is a key to commercialization of the integrated-gasification- combined-cycle (IGCC) power systems. Among the various available coal-to-electricity pathways, IGCC power plants have the most potential with high thermal efficiency, simple system configuration, low emissionsof SO(sub 2), NO(sub x) and other contaminants, modular design, and low capital cost. Due to these advantages, the power plants of the 21st century are projected to utilize IGCC technology worldwide. Sorbents developed for sulfur removal are primarily zinc oxide-based inorganic materials, because of their ability to reduce fuel gas sulfur level to afew parts-per-million (ppm). This project extends the prior work on the development of fluidizable zinc titanate particles using a spray-drying technique to impart high reactivity and attrition resistance. Specific objectives are to develop highly reactive and attrition-resistant zinc titanate sorbents in 40- to 150-(mu)m particle size range for transport reactor applications using semicommercial- to full commercial-scale spray dryers, to transfer sorbent production technology to private sector, and to provide technical support for Sierra Pacific's Clean CoalTechnology Demonstration plant and METC's hot-gas desulfurization process development unit (PDU), both employing a transport reactor system.