Novel papermaking black liquor treatment method and system

The invention discloses a novel papermaking black liquor treatment method and a system. The method includes adding an industrial waste acid into papermaking black liquor sewage to perform an acid eduction processing, after the acid eduction, generating numerous lignin flocs in the sewage, separating the lignin flocs through step by step filtering of a filter tank, feeding a filter liquor after the flocs are separated into a coagulation flotation device, adding chemicals into the device under the pneumatic stirring condition to perform a coagulation, depositing to form flocs, adjusting the potential of hydrogen (pH) value of the sewage which is subjected to the coagulation flotation, and then enabling the sewage to enter into a biochemical system to be subjected to a biochemical treatment. According to the novel papermaking black liquor treatment method and the system, a novel pre-treatment technology is utilized, a lignin acid eduction process is modified, a stable and efficient operation can be achieved, a method of treatment of wastes with processes of wastes against one another is utilized, the treatment cost is lowered, lignin of industrial chemicals can be extracted from the discharged flocs, the resource recovery utilization of a papermaking black liquor can be achieved, the sustainable development of economy can be facilitated, numerous pollutants can be removed in a front-end pretreatment, the follow-up biochemical treatment pressure can be greatly reduced, and thereby the entire process can stably and efficiently operate.