活性污泥合成聚羟基烷酸酯中单体组分的调控

Process regulation for monomer composition of polyhydroxyalkanoates produced by activated sludge

聚羟基烷酸酯(PHAs)是一类生物合成的环境友好高分子塑料,具有广泛应用前景。活性污泥合成PHAs可降低PHAs生产成本,实现废物资源化。PHAs的物化性质取决于其单体组分的结构和含量。基于优化PHAs产量的工艺研究,总结了调控活性污泥合成的聚羟基丁酸-羟基戊酸(PHBV)中羟基戊酰含量的工艺措施和生化原理。已有研究表明,好氧时,碳源类型决定PHBV中的单体组分;一般地,溶解氧浓度(DO)降低,PHBV中HV含量会增加;污泥来源、pH值以及碳源与氮磷浓度比的变化都会影响HV含量;各参数对PHAs组分的影响存在关联性。展望了调控活性污泥合成PHAs中单体组分的进一步研究方向。

Polyhydroxyalkanoates （ PHAs ） are environmental-friendly bio-thermoplastics with the potential of wide application. PHAs synthesis by activated sludge is cost-saving and beneficial for waste recycle. The monomer composition and content of PHAs determine the physicochemical characteristics of the polymer. Based on the technology of optimizing PHAs production, the process manipulation and biochemical metabolism for regulating the hydroxyvaleryl content in poly （3 hydroxybutyrate-co-3- hydroxyvalerate） （PHBV） by activated sludge were summarized. Literature review indicated that under aerobic condition the nature of carbon substrate was crucial to the final composition of PHBV. Generally, decrease of dissolved oxygen concentration （DO） led to hydroxyvaleryl content enhancement, and variation of sludge source, pH and carbon to nitrogen and/or phosphorus ratio all tended to alter hydroxyvaleryl content. The effects of the above parameters on hydroxyvaleryl content were inter-related with each other. Further research to regulate the composition of PHAs from activated sludge was forecasted.