Preparation of Black Liquid Coal Water Slurry Based on Weak Black Liquor for Removing the Evaporation Section

In order to reduce energy consumption of weak black liquor concentration and reduce the emission of sulfur oxide and carbon dioxide, black liquor coal water slurry (BLCWS) prepared aiming to consume weak black liquor directly is studied in this paper. The study found that BLCWS prepared with 66.5% solid content based on coal with low oxygen content and low oxygen carbon ratio presents good fluidity and static stability. BLCWS prepared under the condition of 66.5% solid content, 10 min grinding time, and 1% additive amount achieved the best slurry forming performance. The water-liberating rates of BLCWS are as low as 0.75% after standing for 25 days. The apparent viscosity presented the change curve of descending first and then ascending with the increase of grinding time. BLCWS shows better performance than industrial CWS by evaluating the fluidity and the stability. The research will be helpful in reducing the emission of pollutants and achieving the goal of “ carbon peaking and carbon neutrality” in the pulping and papermaking industry.