微生物絮凝剂及与壳聚糖复配处理亚甲基蓝废水

摘要

A bioflocculant was produced from slaughter wastewater, and the performances in methylene blue wastewater treatment were investigated by using the bioflocculant alone or combined with chitosan. Furthermore, response surface methodology (RSM) was employed to optimize the treatment process by the composite of this bioflocculant and chitosan. Results showed that the optimal culture conditions for bioflocculant production were 2g urea, 2g glucose, 2g K2HPO4, and 1g KH2PO4 dissolved in 1L slaughter wastewater. The corresponding bioflocculant yield reached 2.92g/L after fermentation for 60h at 35°C and 150r/min. For the methylene blue wastewater with a concentration of 20mg/L, when the bioflocculant was adjusted to 15mg/L and the solution pH was 7, removal efficiency of methylene blue reached 64.9%. Optimal conditions for methylene blue removal by the composite of bioflocculant and chitosan were bioflocculant dose of 12.9mg/L, chitosan dose of 0.07g/L, and pH=6. Under this optimal condition, removal efficiency of methylene blue appeared as 94.7%, indicated that it is a feasible way to significantly promoted methylene blue wastewater treatment by using the composite of bioflocculant and chitosan, and the effluent quality was meeting to the 1A discharge standard of the discharge standard of pollutants for municipal wastewater treatment plant (GB 18918-2002).%利用屠宰废水为原料制备了微生物絮凝剂,考察了微生物絮凝剂单独使用或与壳聚糖复配使用处理亚甲基蓝废水的性能,并通过响应面分析法优化了复配处理条件.实验结果显示,制备微生物絮凝剂的最佳培养基组分为1L屠宰废水、2g尿素、2g葡萄糖、2g K2HPO4、1g KH2PO4,在发酵温度35℃、摇床速度150r/min条件下发酵60h后,微生物絮凝剂产量达2.92g/L.对于浓度为20mg/L的亚甲基蓝废水,单独使用微生物絮凝剂处理时,在微生物絮凝剂投加量为15mg/L、废水pH=7的条件下,亚甲基蓝的去除率可达64.9%.响应面分析结果表明,在微生物絮凝剂12.9mg/L,壳聚糖0.07g/L,pH=6的最优复配条件下,亚甲基蓝的去除率达到94.7%,说明微生物絮凝剂与壳聚糖的复配使用显著提高了亚甲基蓝废水的处理效果,达到城镇污水处理厂污染物排放标准(GB18918-2002)一级A标准.