Boiler design criteria for dry sorbent SO/sub 2/ control with low-NOx burners: new unit applications. Final report, October 1985-March 1986

This report describes a study to define boiler modifications required to achieve 70% SO/sub 2/ removal with sorbent injection on a large tangentially fired utility boiler without supplemental spray drying. The study is a follow on to a recently completed broader evaluation of boiler-design criteria for sorbent SO/sub 2/ control technology. A new 500-MWe utility boiler burning low-sulfur coal was considered to be modified to increase sorbent residence time and decrease gas quench rate to achieve 70% SO/sub 2/ removal in the boiler with atmospheric calcium hydrate prepared on-site. A second case was considered where no change was made to gas quench rate or sorbent residence time. The effects of adding a pulverizer to the sorbent preparation/injection system to produce a finer sorbent were determined. Capital costs, cost of electricity, and cost effectiveness per ton of SO/sub 2/ removed were developed and compared with the results of the earlier study.