Black liquor treating and using method for alkaline pulp plant

A process for treating the black liquid generated by alkali-process paper pulp factory features that the black liquid is fermented in multiple pools for 30-40 hr until its pH=7-8, the water is used for irrigation, the organic acid generated during fermentation is used to neutralize the alkali in black dliquid, and the fermented cellulose and lignin in black liquid can be used as organic fertilizer. 本发明的减法纸浆厂黑液治理及应用方法，其关键是：不用将纸浆厂排出的黑液进行处理，直接经管道排到设计好的池槽中，池槽多个并联设计，且都与黑液排出主管道相连，池槽3-5个为一组，多组连成灌溉网，用二氧化碳和黑液发酵过程中产生的有机酸中和黑液中的碱；黑液中的纤维素、木质素发酵后可变为很好的有机肥料，当黑液在池槽中发酵30-40天时，pH值达到7-8，这时即可用于农田灌溉。其优点是节省了黑液治理的大量资金，解决了黑液治理成本高难度大的问题，用于农田灌溉，不仅节省了地下水，又提高了土壤肥力。