油田污水生物处理系统生物强化与节能减排应用基础研究

Given the heavy oil wastewater treatment technology upgrade efflux compliance issues of Henan heavy oilfield, the distribution of the main organic pollutants in the influent of biological treatment system was firstly analyzed to determine the chemical composition of the main residual refractory organics. Then, the luminescent bacteria were used to determine the biological toxicity of sewage to establish the relationship between biological toxicity and biodegradability in oilfield wastewater. The functional flora was constructed by the breeding of high efficient hydrocarbon degrading bacteria and nitrifying bacteria. Through the determination of respiratory rate between anaerobic bacteria and aerobic bacteria, the addition of high efficient bacteria and other measures, the increment of biodegradability and the dosage of functional bacteria was determined, the effect of bioaugmentation was improved, and the theory of bioaugmentation was enriched and improved. In energy saving and emission reductions, bioreactor with internal circulation draft-tube will be used to enhance turbulent mass transfer in this study. The theory of turbulent mass transfer in internal circulation draft-tube will be formed, and new equipments of O/A system for oilfield wastewater treatment will be configurated. Finally, oilfield wastewater discharge will meet the standards through the research. The purpose of this study is to minimise the organic emission, save energy and improve efficiency. The research achievements can be applied to oil and petrochemical industry, coal to gas and oil industry and the treatment of non-degradable organic wastewater, having an important theoretical and practical significance.

针对油田稠油开采污水处理技术升级外排达标问题，首先分析生物处理系统进水主要有机污染物的分布规律，确定主要残余难降解有机物的化学组成。利用发光细菌，测定污水的生物毒性，建立油田污水生物毒性与生物可降解性间的关系。选育高效石油烃高效降解功能菌与高效硝化菌，构建高效处理油田污水的功能菌群。通过测定厌氧菌与好氧菌的呼吸速率、投加高效菌群等措施，测定生物降解能力提高的幅度及高效功能菌用量，提高生物强化的效果，丰富与完善生物强化的理论。应用内循环导流筒生物反应器强化湍流传质，同时建立内循环导流筒强化湍流传质新理论，形成油田污水生物O/A处理工艺新装备，最终实现油田污水升级外排达标。本课题的研究成果可最大限度地减少有机污染物的排放，节能减排、降耗增效，可推广到整个石油、石化含油污水处理领域乃至新兴的煤制气、煤制油及其难降解有机废水的相关行业应用，具有重要的理论与现实意义。

稠油采出水是稠油开采过程中产生的大量含油污水。稠油采出水组成复杂、生物毒性高、可生化性差、高温、高盐等特性，其达标处理成为困扰油田发展的难题。现有的生物膜A/O工艺已不能满足国家不断提高的水质排放要求。因此，开发新型生物膜反应器，结合生物强化方法，解决关键科学问题，提高采出水的处理效率，实现外排水的升级达标、节能减排，具有重要的意义与推广价值。. 本项目研究内容与取得的重要成果如下：(1) 通过研究现有油田污水生物处理系统各功能单元的的主要有机污染物的分布规律，筛选高效降解聚丙烯酰胺及难降解有机污染物的功能菌与表面活性剂高耐性的功能菌。筛选的3株石油烃降解菌(I、K、W)对石油烃有较强的降解能力，培养6d后，降油率可达60.0%以上。2株高效降解HPAM的功能菌为XL-1菌和XL-2菌。其中，XL-1菌使B/C值提高0.1以上，COD去除率最高达到20.5%。2株高耐受化学表活剂的菌为B-3菌和B-4菌，B/C值提高了0.2。建立了生物需氧量（BOD）评价生物膜活性的方法。通过投加菌体（高效菌），提高油田污水的可生化性。(2) 解析了A/O2生物膜工艺各功能单元有机污染物组成变化规律。石油类去除率达90%以上，但COD去除率达70%以上，仍有约30%COD残留于外排水中。(3) 研究了改进型A/O生物膜工艺中试装置的启动与运行，并对各工艺参数（水力停留时间、气水比、COD、BOD、SS、NH3-N、TN-N等）进行了考察与优化。(4) 基于二氯甲烷液液萃取和多壁碳纳米管固相萃取，结合GC-MS和ESI FT-ICR MS分析，建立了一套针对稠油采出水中溶解性有机物组成的综合分析方法。厌氧和好氧单元对烷烃总的去除率分别为43.52%和50.91%，对芳香烃的降解率为68.11%和25.94%，对油田所使用化学药剂的去除率46.5%和41.74%。(5) 掌握了A/O2生物膜工艺微生物群落与丰度在各反应单元的变化规律，厌氧生物膜优势菌为黄杆菌属和红螺菌科，一级好氧生物膜优势菌硝化螺旋菌、苯基杆菌属、柠檬酸杆菌，二级好氧生物膜为黄杆菌属、红螺菌科、黄色杆菌属以及硝基还原假单胞菌，不同的优势微生物决定了各功能单元对污染物降解能力的不同。