【作者】 张志东；

【导师】 刘喜林； 刘永建；

【作者基本信息】 东北石油大学 ， 油气田开发工程， 2011， 博士

【摘要】 辽河油田以开采稠油为主,稠油污水油水密度差小、乳化严重,污水处理非常困难且耗资巨大,是油田生产急需解决的主要问题之一。本文对辽河油田稠油污水回用于热采锅炉的处理技术进行了研究,经过室内实验、现场小试、中试及工程应用实验,证明处理后水质达到设计指标要求,能够回用于热采锅炉。充分利用了稠油污水的水源和水温,回收热能,防止对水体污染,实现污水资源化。所研究的稠油污水处理技术具有推广应用价值。除油系统是整个稠油污水处理流程中的基础和关键。而除油效果的好坏取决于高效净水化学药剂,通过室内实验,筛选出了适用于辽河欢四联、杜84块及兴一联污水处理的破乳剂TJ-1和絮凝剂P-3,确定了最佳投药量。在辽河油田欢四联进行了稠油污水处理现场小试,强化了调节池的除油效果,再通过斜板隔油池和气浮池进一步除油和除悬浮物,最后用高效生物反应器降低污水COD。小试实验表明：高效生物反应器内生物膜量大,对于稠油污水COD的去除起到重要的作用；浮选剂TF-1可起到良好的水质调节作用,当浮选剂浓度为12.5-15mg/L时,油的去除率可达到98%以上,对悬浮物及COD的去除率也可超过96%,水质清澈；破乳剂的投加量为75-100mg/L,絮凝剂的投加量为2-4mg/L,GT值控制在104-105范围内,经过斜板隔油和气浮处理后,水质清亮透明,油含量为1-2mg/L左右,悬浮物为2mg/L左右；气浮池和高效生物反应器出水COD比较稳定,气浮池出水COD基本上在200-300mg/L之间,平均值为261mg/L,而生物出水COD均低于100mg/L,平均为77.6mg/L,达到了国家排放标准,形成了一项适用于稠油污水COD处理的新工艺。对欢四联稠油污水深度处理进行了中试实验,形成了完备的稠油污水深度处理工艺技术,实现了污水回用和排放。前段除油系统中试,确定了最佳运行参数,形成了先除油后除悬浮物技术和高效气浮选技术,研究表明：破乳剂TJ-1和絮凝剂P-3的最佳投药量分别为50-65mg/L和0.5-1.0mg/L时,油、悬浮物和COD的平均去除率可分别达到96.8%、89.6%和93.3%;一般来水含油量每增加100mg/L,破乳剂TJ-1的投加量要相应增加10mg/L,才能达到相同的处理效果；在TJ-1和P-3两者之间,对稠油污水处理效果影响最大的是TJ-1；高效气浮分离器的回流比控制在60%左右最好,产生的溶气水为牛奶状,气泡直径非常细小；浮选剂TF-1的最佳投药量为10-15mg/L时,高效气浮分离器对油、悬浮物和COD的去除率可分别达到97.7%、83.7%和37.1%,其出水中油、悬浮物和COD含量分别为0.65mg/L,32.0mg/L和302.6mg/L,满足后段生物处理系统和软化系统的进水要求。软化系统中试,研究了对硬度、二氧化硅、总铁以及油和悬浮物的去除,确定了主要设备的运行技术参数,形成了一套化学除硅技术、精细过滤技术及弱酸阳离子软化技术。研究表明：石灰和MgCl2投加量的最佳范围分别是300-600mg/L和200mg/L,最佳的pH范围为8.5-9.5；NaOH软化也可有效的去除硬度和二氧化硅,与石灰软化相近,随着NaOH投加量的增加并不会导致混凝沉降罐出水硬度的上升,NaOH软化产生的污泥量仅为石灰软化的1/5,石灰软化产生的污泥量占总处理水量的5%-7%；双滤料过滤器对气浮出水及混凝沉降出水过滤实验表明,处理气浮出水滤料过滤周期为24h,处理混凝沉降出水滤料过滤周期可达32h；气浮出水采用石灰软化、镁剂除硅以及强酸钠离子交换树脂的处理后,可达到进热采锅炉的水质指标。本文研究的稠油污水处理技术在辽河油田欢喜岭采油厂进行了工程应用,处理后污水水质达到设计指标,能够回用于热采注汽锅炉。更多还原

【Abstract】 Liaohe Oilfield is mainly in the production of high-viscosity oil. The treatment of high-viscosity oil wastewater, one main problem to be resolved in oil production, is difficult and costly, due to characteristics of wastewater, such as small density difference between water and oil, and severe emulsification. In this paper, a lot of research on the technology of wastewater reuse in thermal recovery boiler was done from laboratory experiment to small-scale, pilot-scale and engineering tests. Results showed that the treated water can be reused in thermal recovery boiler because its quality has reached design requirements of thermal recovery boiler. This technology can make good use of source and temperature of the high-viscosity oil wastewater, recover energy, prevent the pollution to water bodies, and eventually realize the reclamation of wastewater. Consequently, this new technology has high application value.Oil-removal system is basic and key in the whole treatment process of high-viscosity oil wastewater. Oil-removal effect depends on efficient water-purification chemicals. Through laboratory experiments, demulsifying agent TJ-1 and flocculants P-3, which are efficient in wastewater treatment of Huansilian, Du 84, Xingyilian of Liaohe Oil Field, were successfully developed. Moreover, their dosages were optimized.Small-scale tests were carried out at Huansilian, Liaohe Oil Field. The oil-removal effect of regulation tank was strengthened, after the inclined-plane oil separation and floatation pretreatment to further remove oil and suspended matter, wastewater was treated by the efficient bioreactor to reduce COD. The results indicated that:A lot of biological film in efficient bioreactor plays an important role in the removal of COD in high-viscosity oil wastewater. Floatation agent TF-1 serves as a good regulator of influent quality. When the dosage of TF-1 was 12.5～15 mg/L, the removal rate of oil was above 98%, and that of suspended matter and COD were both above 96%. After the treatment, the water appeared clear and transparent. When the dosages of demulsifying agent and flocculants were 75～100mg/L and 2～4mg/L respectively, the value of GT was in the range of 104～105. After the treatment of inclined-plane oil separation and floatation, the water became clear and transparent; the content of oil was 1～2 mg/L, and that of suspended matter was about 2mg/L. The COD in treated water from floatation pool and efficient bioreactor was relatively stable. Besides, the COD in treated water from floatation pool was basically in the range of 200～300mg/L, and its average value was 261mg/L, while the COD in treated water from efficient bioreactor was less than 100mg/L, and its average value was 77.6mg/L. Both of them had met the national emission standards. And this COD treatment process is a new one in wastewater treatment of high-viscosity oil.During pilot-scale tests at Huansilian in advanced treatment of high-viscosity oil wastewater, a complete series of process technology gradually took shape, reaching the recovery and discharge standards. The optimum running parameters were fixed during preceding pilot-scale tests in oil-removal system, forming suspended-matter removal technology and efficient flotation technology after oil-removal. The results showed that when the optimal dosages of demulsifying agent TJ-1 and flocculants P-3 were 50～65mg/L and 0.5～1.0mg/L separately, the average removal rates of oil, suspended matter and COD reached 96.8%,89.6% and 93.3% respectively. In general, when the content of oil in source water increases by 100mg/L, in order to reach the same effect, the dosage of demulsifying agent TJ-1 must increase correspondingly by 10mg/L. Compared with P-3, TJ-1 has greater impact on the treatment effect. The most preferable reflux ratio of efficient flotation separator was 60% approximately; the generated gas-soluble water was milky liquid, and the diameter of bubble was very small. When the dosage of flotation agent TF-1 was the optimal value 10-15mg/L, the removal rates of oil, suspended matter and COD reached 97.7%,83.7% and 37.1% separately in efficient flotation separator. Besides, the oil, suspended matter contents and COD in its treated water were 0.65mg/L,32.0mg/L and 302.6mg/L respectively. The results had met the requirements of supplying water for late biological treatment system and softening system.The removal of hardness, silica, total iron, oil and suspended matter was studied in pilot-scale tests of softening system. The running technical parameters of major equipments were fixed in the tests, forming a set of silica-removal, fine filtration, weak-acidic cation softening technologies. The results indicated that the optimum dosages of lime and magnesium chloride were 300～600mg/L and 200mg/L respectively; the best pH range was 8.5～9.5. The sodium hydroxide softening removed hardness and silica effectively, having similar effects with lime softening. Besides, dosage increase of sodium hydroxide didn’t lead to hardness increase of effluent water from coagulation tank. What’s more, sludge in sodium hydroxide softening treatment was only one-fifth of that which accounted for 5%-7% of total wastewater in lime softening treatment. Effluent water from floatation pool and coagulation tank was filtrated respectively in dual-media filter, and the results showed that the filtration cycle of water from floatation was 24h, while that of water from coagulation was 32h. After the treatment by lime softening, silica removal with magnesium compound and the strong-acid sodium ion exchange resin, the effluent water from floatation pool had come up to standards of water supply to thermal recovery boiler.This technology of wastewater treatment has been in engineering application at Hanxiling Oil Plant of Liaohe Oil Field. The quality of treated wastewater has met the recovery standards of thermal recovery boiler.更多还原