毛竹化学机械浆浓废液碱回收性能及混合废液处理技术的研究

Study on the Alkali Recovery Performance and Mixed Wastewater Treatment Technology of Effluent from Bamboo Chemical Mechanical Pulping Process

对毛竹化机浆制浆过程产生的浓废液进行物化分析,以评估其进行碱回收的可能性;并采用厌氧-好氧+Fenton深度氧化工艺对其混合废液(混合后续工段的废液包括纸机白水、洗涤水等,COD_(Cr)浓度2950 mg/L)进行处理,研究了其排放水质情况。结果表明,毛竹化机浆浓废液的流变性优于同浓度的竹化学浆黑液,氯含量(0.94%)与竹化学浆黑液接近;发热量(高位为11.91 MJ/kg固形物、低位为10.89 MJ/kg固形物)及膨胀体积(19.52 mL/g)均略低于竹化学浆黑液;竹化机浆废液固形物浓度与波美度成线性关系,关系式为Y=1.5196X-1.693,表明其可采用碱回收技术进行处理。混合废液经厌氧-好氧+Fenton深度氧化处理后,COD_(Cr)去除率为97.3%,最终出水达到《制浆造纸工业水污染物排放标准》(GB 3544—2008)的要求。

The physical and chemical characteristics of effluent from bamboo chemical mechanical pulping process were analyzed to evaluate its feasibility of alkali recovery,and the anaerobic-aerobic+Fenton deep oxidation process was used to treat its mixed wastewater(including white water and washing water of paper machine with COD_(Cr) concentration of 2950 mg/L)to study the discharge water quality in this study.The results showed that the rheological property of concentrated effluent from bamboo chemical mechanical pulping process was better than that of black liquor from bamboo chemical pulping process at the same concentration.The chlorine content of concentrated effluent(0.94%)was closed to that of bamboo chemical pulping black liquor.Both calorific value(high calorific value was 11.91 MJ/kg,low calorific value was 10.89 MJ/kg)and expansion volume(19.52 mL/g)were slightly lower than bamboo chemical pulping black liquor.There was a linear relationship between the solid concentration(Y)and Baume degree(X)in the concentrated effluent with the relationship equation of Y=1.5196 X-1.693,indicating that alkali recovery technology could be used for its treatment.After the mixed wastewater was treated by anaerobic-aerobic+Fenton deep oxidation,the removal rate of COD_(Cr) was 97.3%.The qualities of the treated effluent could meet the demand of Discharge Standard of Pulp and Paper Industry Water Pollutants(GB 3544—2008).