复杂工业废水生物降解浓度趋零的抑制因素与动力学

Biological treatment of complex industrial wastewaters such as fine chemical wastewater, dyeing wastewater, coking wastewater and landfill leachate can not lead to a complete removal of organic wastes due to their high chemical stability and low biodegradability. The feature of incompleteness requires the combination of biological treatment with other technologies like coagulation, adsorption and advanced oxidation process, which however induces the second contamination due to the addition of chemicals. Based on these considerations, this research proposal will first focus on investigating the adsorbability, hydrophobicity and conductivity of the effluents of biologically treated industrial wastewaters because these characteristics are believed to be closely related with their biodegradability. Then, special emphasis will be placed on cultivation of functional microorganisms formed on the sludge particles or floc under oligotrophic conditions; analysis of their colony characteristics, evaluation of the abundance changes of the uncultured microorganisms; and correlation of them with the inhibitory factors like adsorbability and hydrophobicity. Furthermore, a biochemical reactor equipped with suspended and loaded functional microorganisms will be designed and constructed. Experiments will be conducted to study the effects of solution property on the biodegradation of pollutants when the conditions of concentration, loading, dissolved oxygen, nutritional composition are stable. Based on the analysis of the mechanism, the model of inhibition kinetics will be established. This study will show insights into the development and application of bioreactors for advanced wastewater treatment.

工业园区精细化工废水、染料化工与印染废水、焦化废水、垃圾渗滤液等均表现出成分复杂以及生物抑制的特征，生物降解过程很难实现彻底的污染物去除。生物处理的不彻底性要求追加深度处理工艺如混凝、吸附、氧化等，药剂的投加不可避免，给水体带来二次污染。基于此，在对生物处理尾水以及达标浓度附近代表性工业废水进行水质成分统计分析基础上，归纳溶液特性，尝试废水可吸附性、疏水性、电导性等指标约束的生物降解规律性的研究，培养基于寡营养条件下污泥颗粒（或菌胶团）形成的功能微生物，分析菌落特征，对功能性未培养微生物丰度的变化进行考察，关联可吸附性、疏水性等因素可能的抑制作用；通过设计基于功能微生物悬浮与负载结合生长的生化反应器，在浓度、负荷、DO、营养组成等因素稳定条件下考察溶液性质变化对污染物浓度趋零降解的影响，分析机理，建立抑制动力学方面的归纳。上述工作可以指导废水深度处理生物技术反应器的开发与应用。

复杂工业废水成分复杂，难生物降解，不利于资源回用，排放对生态环境构成威胁。研究废水溶液性质特征与水质指标间的关联性，建立指示性质的特征光谱参数，从官能团、分子结构等角度解析性质与指标间相对应的科学依据。分析微生物菌群结构特征，结合胞外聚合物、活性特征，证明污泥系统异质化的存在。构建高效生物流化床系统，研究反应器处理废水的效率和最佳条件，探索同步除碳脱氮技术。分析废水难生物降解的抑制因素，从有机物极性和特征污染物角度考察抑制因素的作用原理，深入剖析水质和生物难降解性之间的内在关系。应用纳米吸附、臭氧氧化、催化氧化等深度处理技术，研究去除复杂工业废水污染物的过程机制和可行性，建立反应动力学模型。研究发现，焦化废水溶解性有机物中疏水性酸性组分和亲水性组分占主要。无机氮化合物是总氮主要部分，全过程占比均超过75%。UV270与废水COD和DOC 值呈强线性相关，能够指示酚类、杂环类和多环芳烃等物质。活性污泥异质性源于离散型污泥中胞外聚合物含量高，亲水性强，比重小。聚结型污泥的基质利用率、比好氧速率更好，微生物菌落结构分布也存在优势。在微电流和Cu2+强化作用下，构建自养反硝化和异养反硝化协同体系，实现同步脱氮除碳目标。疏水性组分和氰类化合物，是抑制生物可降解性的因素。水热合成铁锌氧体比非催化氧化加速苯酚降解1.5倍。催化剂作用下，焦化废水臭氧氧化有更高矿化率，芳香族和共轭结构物质被去除。项目从水质特征、微生物群落、反应器到抑制因素、深度处理技术、反应动力学等方面，全方位研究了复杂工业废水污染物和水质参数趋零的抑制因素和技术可行性。具体开展了水质结构分析、微生物菌群分布、高效生物流化床反应、组分和化合物对微生物活性的抑制、臭氧催化氧化机制等科学和技术方面的探索，为工业废水浓度趋零、新型环境材料、水质实时监测、水资源回用、污染物毒性和生态风险评价等工作，提供了理论指导和基础数据。