复合电解电化学法处理桉木化学机械浆制浆废液及其机理分析

针对化学机械浆废液有机物浓度高、色度深、处理难度大的问题,应用复合电解电化学法处理桉木化学机械浆制浆废液,探讨了各工艺条件对处理效果的影响,并对机理进行分析.结果表明:CODcr和色度去除效果受pH值、槽电流和通过量的影响,较低的pH值、较低的通过量和较高的槽电流有利于提高废液的处理效果;在pH为4、槽电流为0.5A、通过量为40ml/min的条件下,CODcr和色度去除率分别达到60%和92%.红外光谱分析表明,复合电解处理过程发生了羰基和木素结构的破坏,这可能是处理后废液色度大幅降低的重要原因;气相色谱-质谱联用(GC-MS)分析表明,废液经过复合电解电化学法处理,芳香族类化合物相对含量减少,非芳香族类化合物相对含量显著增加,表明部分芳香族化合物的结构在处理过程中发生断裂破坏,生成了非芳香族的有机物,有利于降低废液毒性,提高可生物降解性.该方法可用于化学机械浆制浆废液生物处理前的预处理.

Eucalyptus Chemimechanical Pulp Effluent Treatment with Composite Electrolysis Electrochemical Method and Mechanism Analysis

To solve problems of high concentration of organic compounds,deep color and high treatment difficulty for chemimechanical pulp effluent,composite electrolysis electrochemical(CEE)method was used to treat eucalyptus chemimechanical pulp effluent,and effect of technological conditions on treatment efficiency was discussed and the mechanism was analyzed.Results showed that CODcr and color removal efficiency was influenced by pH,cell current and flow rate,and the treatment efficiency increased at lower pH,lower flow rate and higher cell current,and that under conditions of pH of 4,cell current of 0.5A and flow rate of 40ml/min,CODcr and color removal rates were 60% and 92% respectively.IR analysis indicated that destruction of conjugate carbonyl and lignin structure happened during CEE treatment and was possibly the important reason of obvious color removal of the effluent after CEE treatment.GC-MS analysis showed that content of aromatic compounds decreased and non-aromatic compounds content obviously increased after CEE treatment,which indicated that structures of some aromatic compounds were destroyed and non-aromatic compounds produced during CEE treatment,and that toxicity of the effluent decreased and biodegradability enhanced after CEE treatment.The method could be used for pretreatment of chemimechanical pulp effluent before biological treatment.