生物强化技术及其在污水处理中应用研究评述

Bioaugmentation Technology and Its Application in Wastewater Treatment

在传统废水生物处理过程中,难降解有机污染物的存在和外界环境的变化会抑制土著微生物的活性,从而影响废水处理效果。生物强化技术是向生物处理系统中引入特定的高效降解功能微生物,通过微生物自身所具备的降解机制对污染物质进行降解,达到有效处理废水的目的。相较于传统生物处理法,生物强化技术能更好地提高难降解污染物处理效果,维持系统的稳定性,减少污泥的产生,缩短系统的启动时间,并可以使系统表现出良好的抗冲击负荷能力。目前生物强化技术研究主要集中在高效菌群对难降解有机污染物的高效降解作用和优势菌种对于极端环境的耐受能力等方面。文章综述了生物强化技术的作用机理,主要有高效菌通过自身携带的降解基因或分泌的降解酶对污染物质的直接降解作用、微生物的共代谢作用和群体感应作用;介绍了生物强化技术中优势菌种的3种获取方式,分别是从自然界中直接进行驯化筛选、构造基因工程菌以及通过水平基因转移获取的方式;论述了生物强化技术的作用形式,包括直接将微生物投加到目标水体中、应用微生物固定化技术和研制生物强化菌剂进行投加的3种方式;另外还总结了近几年来生物强化技术在景观水体、土壤修复、产能和水处理等方面的应用,最后阐述了生物强化技术研究存在问题和新路径。

In the traditional wastewater biological treatment process,the presence of refractory organic pollutants and changes in the external environment will inhibit the activity of indigenous microorganisms,thereby affecting the wastewater treatment effect.Bioaugmentation technology is to introduce specific high-efficiency degradation functional microorganisms into biological treatment systems,to degrade pollutants through the degradation mechanism of the microorganisms themselves,and to achieve the purpose of effective wastewater treatment.Compared with traditional biological treatment methods,bioaugmentation technology can better improve the treatment effect of refractory pollutants,maintain the stability of the system,reduce the generation of sludge,shorten the startup time of the system,and make the system show good shock load resistance.At present,the research on bioaugmentation technology is mainly focused on the efficient degradation of refractory organic pollutants by high-efficiency bacteria and the tolerance of dominant bacteria to extreme environments.This article reviews the mechanism of bioaugmentation technology.It mainly includes the direct degradation of polluting substances by high-efficiency bacteria through their own degradation genes or secreted degrading enzymes,microbial co-metabolism and quorum sensing effects;Introduces three ways to obtain dominant strains in bioaugmentation technology,namely domestication and screening directly from nature,construction of genetically engineered bacteria,and horizontal genes ways to transfer and acquire;Discusses the action forms of bioaugmentation technology,including three methods of directly adding microorganisms to the target water body,applying microbial immobilization technology and developing biofortified bacteria agents;In addition,it also summarizes the application of bioaugmentation technology in landscape water bodies,soil restoration,productivity and water treatment in recent years.Finally,the problems and new paths of bioaugmentation technology research are described.