Method for preparing flocculating agent by using papermaking sludge

• Main Authors: YUE QINYAN, ZHANG FEI, RONG HONGYAN, GAO BAOYU, SUN FANGFANG, ZHANG BEI, WANG YAN, LI QIAN
• Format: Patent
• Language: Chinese; English
• Published: 28.08.2013
• Subjects: CHEMISTRY; METALLURGY; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

The invention relates to a method for preparing a flocculating agent by using papermaking sludge. The method comprises the following steps of: with papermaking sludge generated in the process of papermaking by using an alkaline process as the raw material, dissolving lignin in the papermaking sludge by using an alkaline liquid; transferring the mixed solution into a reactor; heating the reactor to a certain temperature, and then, adding anhydrous sodium sulfite to react for a period of time; next, sequentially adding hydrogen peroxide and formaldehyde into the reactor, stirring and reacting for a period of time, and then, adding sodium sulfite to continue to react for a period of time; cooling the reactor and adding urea to react; and filtering floccules in a supernatant liquid to obtain the flocculating agent. When the flocculating agent product is used for pretreating the actual water sample of soy protein, the addition amount of effective products is 370-375mg/L, the removal rate of COD (Dissolved Organic