Combustion and Sulfur-fixing Performance of Pulping Black Liquor Coal-water Slurry

keywords:pulping black liquor  coal-water slurry  combustion performance  sulfur-fixing performance

Abstract:The effects of adding pulping black liquor and other additives to coal-water slurry (CWS) on the sulfur-fixing performance of the resultant mixture (pulping black liquor coal-water slurry) were evaluated. The experimental results demonstrated that the ash content of the black liquor coal-water slurry decreased as the addition of pulping black liquor in the mixture increased. Nevertheless, the addition amount should be appropriately selected to ensure that the black liquor coal-water slurry had a moderate calorific value. Addition of black liquor improved the combustion performance of CWS by lowering the ignition point and stabilizing the combustion process; moreover, the sulfur-fixation ratio after combustion increased by 12 to 16 percentage points than that of CWS, and the content of high-melting-point salt in the ash from CWS after adding black liquor was low. The sulfur-fixing ratio of CWS after adding a sulfur-fixing agent was effectively increased by 25 to 30 percenatge points, but with compromise of the fluidity and stability of the CWS; thus, the addition amount of a sulfur-fixing agent should be optimized.