混凝-生物强化联合处理环氧树脂高盐废水

环氧树脂高盐废水是目前较难处理的工业废水之一.采用混凝联合生物强化工艺:通过混凝过程进行预处理后,投加嗜盐菌进行生物强化考察盐度变化对系统降解有机物的影响以及污泥性状的变化情况.结果表明,当废水中氯离子浓度达到驯化目标10 g/L时,系统对COD的去除率仍稳定在85%左右;以没有投加嗜盐菌的反应器为对照组,在进水COD平均浓度为550 mg/L左右,氯离子浓度由12 g/L增至21 g/L时,对照组COD平均去除率由82%降至60%以下,而投加了嗜盐菌的反应器(投加组)则仍保持在85%以上;此外,盐度的变化同时影响污泥的活性及其沉降性能,随着盐度增大,两组中的污泥活性均有所降低,但投加组的污泥活性相对较高,其污泥的沉降时间和污泥体积指数(sludge volume index, SVI)值也较低.采用本工艺处理环氧树脂高盐废水,使得生物处理过程能够长期稳定运行,且能够保持较高的耐盐度和COD去除率.

Coagulation-bioaugmentation combined treatment of high-salty epoxy resin wastewater

Currently the high salinity wastewater generated in the epoxy resin manufacture process is one of the typical wastewaters that are difficult to be treated. In this study, a combined coagulation and biological process was developed to treat such high salinity wastewater. Coagulation process was performed as the pretreatment step and the wastewater was further treated by the halophilic bacteria enriched sludge supplemented biological reactor. The effects of salinity on the degradation efficiency of organic matters in the wastewater and the sludge characteristic were investigated. Results indicated that when the Cl- in the wastewater increased to the target value of 10 g/L, the chemical oxygen demand (COD) removal efficiency was around 85% which was pretty stable. When the influent COD was 550 mg/L and the Cl- further increased to 21 g/L, the COD removal efficiency in the halophilic bacteria enriched sludge supplemented system was still remained at more than 85%. However, the COD removal efficiency in the control reactor decreased from 82% to 60%. Variation of the water salinity influenced the activity and settable capacity of the activated sludge in the two systems. Sludge activity in both systems decreased with the increasing of salinity, but it was relatively higher in the halophilic bacteria enriched sludge supplemented system. Similar results were achieved for the settling time and sludge volume index (SVI) of the sludge. When this developed process was utilized, the biological treatment unit can be operated at stable state for a long term and simultaneously high salinity and COD removal efficiency were kept.