On Sorbent Activation in Coolside Desulfurization

Abstract

In a coolside desulfurization process, partly unreacted sorbent from the boiler injection, or fresh sorbent injected into the flue-gas duct, is activated by a water spray. Primarily as a result of Inertial impactions between the sorbent particles and the water droplets, highly active slurry droplets are formed. In this paper, a theoretical model for the calculation of the sorbent activation efficiency is derived. The influence of design and operating parameters on the activation has been calculated with a simulation program. The initial mean value and standard deviation of the droplet diameter and the difference in Initial velocity between the droplets and the flue-gas are shown to be the most important parameters in addition to the water/gas ratio. The sorbent particles are activated primarily in the vicinity of the atomizing nozzles.