提高生态浮床系统脱氮除磷效率研究进展

Advance in Improving the Removal Efficiency of Nitrogen and Phosphorus of Ecological Floating Bed System

生态浮床系统处理技术因具有投资少、易操作、无二次污染兼具良好景观性等优点而被广泛应用于各种类型污染水体的治理。生态浮床系统是一个复合生态工程系统,其对污染的去除机理是一个错综复杂的过程,填料、水生植物、水生动物和微生物共同发挥着重要作用。主要概述生态浮床系统的发展状况、脱氮除磷机理、限制因素及存在问题;重点概述以细菌固定化技术和曝气等方式的外在法和以改进生态浮床系统构造形式、筛选优势浮床植物等方式的内在法,来提高生态浮床系统脱氮除磷效率;展望了生态浮床污水处理系统未来的研究与应用前景。

Nitrogen and phosphorus contained in agricultural effluents and industrial wastewaters were mainly responsible for water eutrophication.At present,there were many approaches can be used to remove nitrogen and phosphorus,such as the constructed wetland,the ecological floating bed,etc.Ecological floating bed processing technology,as a kind of wastewater treatment technology with high efficiency,low costs,easy-operation,no secondary pollution and excellent landscape,was widely used for the restoration of eutrophic water bodies such as lakes,streams,reservoirs and ponds.Some floating bed can provide economic returns and generate valuable products,e.g.,biogas,bio-fertilizer,biomaterial,and even animal food.Ecological floating bed was an integrated eco- engineering system.The pollutants removal functioning were also a complex processes, in which substrate,aquatic plants,aquatic animal,microorganism play the important role together.On one hand,the floating bed plants can absorb the nitrogen,phosphorus and other elements as nutrition on their growth processing,remove the nitrogen and phosphorus from the water by harvesting aquatic plant.The floating bed plant roots also adsorb the suspended particles;on the other hand,the microorganisms which attached on the plant roots and substrate played the major role in removing pollutants;some plants can secrete chemical grams of biomass to inhibit the growth of phytoplankton;some plants can improve water conditions by secrete oxygen for aerobic microorganisms.This paper illustrated the floating bed development progress,efficiency and functioning of nitrogen and phosphorus removal,limited factors and existing problems,mainly illustrated the external methods such as bacteria immobilized technology,aeration and the inherent methods such as improving the structural form of ecological floating bed,screening advantage aquatic plants to enhance the efficiency of nitrogen and phosphorus removal in the floating bed system.Prospect the further research and application on ecological floating bed processing technology in wastewater treatment.