SO2 SCRUBBING BY ULTRAFINE CA(OH)(2) AEROSOL

The objective of the present study was to generate submicrometer calci um hydroxide aerosols and to investigate the effectiveness of such aer osols in sulfur capture. The effectiveness of SO2 removal by Ca(OH)(2) aerosol has been investigated in an isothermal reactor. Ca(OH)(2) aer osol was generated by a novel fluidizer system in which submicrometer- sized powders were entrained in gases. SO2 was added to this aerosol t o a concentration of 2000 ppm. The aerosol-SO2 mixture was heated to 5 50 degrees C-750 degrees C in an isothermal tube reactor. The SO2 remo val efficiency, which varied from 20 % to 70 %, was determined to be a function of the aerosol concentration, reactor temperature and reside nce time. The fraction of aerosol reacted was not affected strongly by the aerosol concentration. The reaction kinetics were determined from the experimental data using a simple analytical model in which the ra te is first order in both SO2 and calcium hydroxide aerosol concentrat ions.