Method for comprehensively utilizing alkaline pulping black liquor

The invention discloses a comprehensive utilization method of alkaline pulping black liquor, which comprises the following specific steps: S1, sulfonation: taking the black liquor as a main raw material, adding a sulfonating agent into the black liquor, and reacting to obtain a reaction product, namely sodium lignin sulfonate; s2, compounding: adding one or more of a dispersing agent, a stabilizing agent or an air entraining agent into the sodium lignin sulfonate; compared with the prior art, the papermaking black liquid is used as the basic raw material, different auxiliary materials are added according to different needs, the papermaking black liquid is comprehensively utilized and converted into various products in different fields, the problem that the papermaking black liquid is difficult to treat is solved, meanwhile, the production cost of downstream industries is reduced, and the environmental protection benefit and the economic benefit are remarkable. 本发明公开了一种碱法制浆黑液综合利用的方法，其中，其具体步骤为：S1、磺化，以黑液为主要原料，向黑