Mercury Control with Activated Carbon: Results from Plants with High SO_3

摘要

The presence of SO_3 in the flue gas, whether as the result of high-sulfur coal, the presence of an upstream SCR, or an SO_3 injection system for flue gas conditioning, can impair the effectiveness of activated carbon for mercury removal. Full-scale evaluations of sorbent injection for mercury removal have been conducted over the past two years to characterize and assess alternatives to enhance mercury removal. These tests have been funded by DOE/NETL, EPRI, and electric generating plant industry partners. This paper will present results from testing including the testing of traditional and alternative sorbents on mercury emissions, the influence of SO_3 concentration and flue gas temperature on mercury removal efficiency, and the effectiveness and economics of dual injection for SO_3 and mercury control.