Technical Bulletin No. 0674: A Study of Kraft Recovery Furnace Hydrochloric Acid Emmisions

HCl emissions from 21 NDCE furnaces (10 tested by NCASI and 11 tested by individual mills) averaged 0.26 lb/ton BLS (range, 0.00 to 1.23). For ten DCE furnaces (four tested by NCASI and six tested by individual mills), the average HCl emission rate was 0.18 lb/ton BLS (range, 0.0 to 0.52). NDCE furnaces, the stack gas HCl concentration was found to correlate strongly with stack sulfur dioxide concentrations and was predicted fairly well by a Langmuir adsorption isotherm-type relationship viz: Y= 1.28 * X/(1 + 0.017 * X), where Y and X are the HCl and sulfide ion concentrations at dry stack conditions, respectively.