| China is classified as one of 13 countries which the water resources is shortage by the UN, insufficient freshwater resources is one of the most serious problems in China. Our country is a water-poor country, accompanied by increased pollution of surface water, groundwater exploitation, such as situation. According to incomplete statistics, the country currently has a lot of regional groundwater "landed funnel," and even some cities there have been land subsidence. Daqing City is faced with these same questions. Therefore, the research, development and application of sustainable use of water resources and water reuse technology has been greatly attention.In China, the main means of mining in oilfield is water flooding oil. At present, the majority of our oilfield is now at the late of development, water content of produced liquid is more than 90%,more than 500 million tons oil field produced water is generated every year. At the same time, as the oil field exploitation, moisture content of oil recovery is also more and more high, produced water will be much more and more. If this portion of oily wastewater treatment without a qualified emissions surrounding environment will be enormous harm, but also waste a lot of water. The purpose of this research lies in after the treatment of oilfield produced water realizing injection, the balance of injecting water and mining water and sustainable development. In order to avoid damage oil and water injection system, clogging of suspended solids and oil in the produced water which is used to inject must reach the injected water quality standards and the external drainage must meet the requirements of local environmental discharge standards.Oil resources in Daqing is exploited for 60 years, with the water-content in old oil fields of placanticline rising, the output gradually declined, increasing development of low permeability and ultra-low permeable oil field is one of the important measures to delay declining rate of the Daqing oilfield production and safeguard national strategic oil safety. With the constant deepening of field development and ultra-low permeable oil field development Rethink, In order to ensure sustainable development of oil fields, oil companies set forth new requirements about injection water quality standards of extra low permeability reservoirs. ultra-low permeable reservoir water quality must meet the "5.1.1" standard, that is, oil content≤5mg/L,suspended particles of solid content of≤1mg/L,suspended matter particle size in the value of≤1μm.At present, oily wastewater treatment process can only achieve "8.3.2" standard, can not satisfy the "5.1.1" water quality requirements, therefore required to select water treatment technology which is economic, efficient and easy to manage for production to carry out pilot studies, finally determine oily wastewater treatment process which fit special characteristics of low permeability oilfield, provide the experience to draw on for resolving the problem that is water-drive ultra-low permeable oil oily wastewater treatment can not reach the standards.This thesis aims to treated wastewater, through the test, new technology and water treatment to process parameters of produced water was determined, and it can provide technical support for recycling and using. To this end, this thesis has undertaken the following work:(A) Injection and production water in yushulin oil field were investigated, and know of its produced water treatment situation, consider whether it is from the perspective of handling capacity or from the water quality after treatment start, is very necessary to have its sewage treatment process for the wastewater treatment process.(B) Selecting Dong 16 in yushulin oil field for testing: doing the structure of Aeration tank and process parameter optimization studies; doing the treatment effect of CAF and process parameters studies; doing a stream of sand filters and filter media Glauconite dual filter structure and water treatment on the principle of respect and, through field trials of the filtering effect of both a comparative analysis; conducted a study on the mechanism of ultrafiltration membrane filter, and through on-site testing on the membrane before the vote add the concentration of pharmaceutical, filtration cycle selection, the selection of hydraulic cleaning time and membrane chemical cleaning, etc. have been studied. Through the "oxidation of aeration+ CAF+ sand filter+ PVC ultrafiltration membranes" Produced water treatment technology pilot study conducted to optimize the process parameters so that the process of the indicators of the stability of the water to membrane separation Technology influent water quality requirements; to carry out ultra-low permeable oil field produced water separation efficiency of membrane separation technology and field application of the stability test, to determine the optimum operating parameters. Through" Doing 16 pilot areas in Yushulin oilfield "of the pilot study, eventually identified as technically feasible, and fit the characteristics of ultra-low permeability oil fields of oily wastewater treatment process.(C) To carry out economic evaluation analysis; through identified technically feasible, and fit the characteristics of ultra-low permeability oil fields of oily wastewater treatment technology for economic evaluation analysis, and ultimately determine "Oxidation Aerated+ CAF+ sand filter+ PVC hollow fiber ultrafiltration membrane "technology in the economy also is feasible.(D) Doing the analysis process about the production operation of oily wastewater treatment technology and making the necessary adjustments about adding to the amount of drugs, etc. thereby improving the oily wastewater treatment process.Through the above research, this thesis has been made aware of the following aspects:1. Oxidative desulfurization techniques: silicone rubber membrane aeration tube in aeration tank can uniform cloth gas, make the air and oily wastewater react fully, remove oily wastewater reducing, reduce the influence of follow-up equipments and pipeline corrosion. Aeration can remove all of the basic sulfur, and can remove some oil, so that to restore divalent sulfur, suspended solids contentis higher than the water.2. Water, solid-liquid separation technology: CAF can be highly effective degreasing, air bubbles produced by small diameter, at between 5-100μm,can effectively remove small-diameter particles. Flotation and has the following advantages: low noise, no pump, no air compressor and pressure vessels, non-underground pipeline, running low-cost, small footprint, management and so on. For oily wastewater water quality in Yushulin oilfield, air-flotation before the vote add 230ppm concentration of PAC and concentration of 3ppm of PAM, the effluent water quality meets the required standard.3. Rough filtration technology: Glauconite has not easily broken, filter effect is good. Glauconite media abrasion, broken performance, filter effects, renewable backwashing filter is better than quartz sand.4. Precision filter technology: the layer of thick filter in flow sand filter guarantees the stability of water quality, non-stop delivery to enable the anti-laundering operations management more convenient. In addition, it can be round-the-clock continuous operation without periodic backwashing outage; the use of uniform media, filter effects stability; and low consumption, high degree of automation; easy maintenance operations, the basic need people to operate.5. Hollow ultrafiltration membrane separation technology: PVC hollow fiber ultrafiltration membrane with a filter pore size small and uniform pore characteristics, so that the membrane filtration and high precision, membrane less susceptible to pollution, easy to clean.6.To "Oxidation Aerated+ CAF+ sand filter+ PVC hollow fiber ultrafiltration membrane," as the core of oily wastewater treatment technology, to meet ultra-low permeable oil field deal with the requirements of oily wastewater, treated water to achieve "5 -1-1 "water quality standards.
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