A 2-STAGE REACTOR FOR STUDYING SORBENT REACTIVITIES IN FLUE-GAS DESULFURIZATION SYSTEMS UTILIZING A FABRIC FILTER COLLECTOR

A two-stage reactor has proven superior in understanding the complex r eactions involved in dry gas-solid reactions responsible for flue gas desulfurization in the medium temperature range (425-650 degrees C). T raditionally, experimental approaches have concentrated on either the in-duct reactivity portion of these reactions, or the reaction in the particulate collector, usually a fabric filter (baghouse). From these current studies we have found that sorbent injection conditions upstre am of a fabric filter affect the continued reactivity of the sorbent o n the filter as well. Considering the sorbent reaction history in its upstream injection zone is therefore important. An integrated hue-stag e reactor system is described which was designed to simulate the seque ntial sorbent reactions from the injection zone to the filtration stag e. The experimental results for Ca(OH)(2) reacting with SO2 in a singl e-stage Fixed-bed reactor system are compared with our results for thi s reaction where sorbent conversions and surface area evolution in a b aghouse were simulated. The comparison shows that because of the disti nctive conditions in the injection and filtration stages, the sorbent reactions in the injection zone are very different from those in the f ixed-bed and they can seriously alter the subsequent sorbent reactions in the filtration stage. The results from the single-stage fixed-bed reactor misrepresent the sorbent reactivity and its physical structura l change during the reactions.