【作者】 邵本东；

【导师】 卓兴家； 李军；

【作者基本信息】 大庆石油学院 ， 石油与天然气工程， 2009， 硕士

【摘要】 辽河油田原油属典型的特高蜡原油,含蜡量变化在8—53%之间,其中含蜡量大于30%的高蜡原油占储量的77%以上。在原油采出过程中,原油在近井地带向井筒运移的过程中温度不断下降,造成原油蜡的析出,析出的蜡聚集在近井地带造成井筒堵塞或蜡卡管柱,油井结蜡问题十分严重,油井产量逐渐下降,洗井费用很大。对结蜡井实施清、防蜡措施,是保证高含蜡井正常生产的重要手段之一。油井清防蜡方法主要有机械清蜡、油管内衬和涂层防蜡、强磁防蜡、化学剂清防蜡,微生物清蜡,其中,微生物清蜡具有施工简单,操作费用低,作用周期长,不影响油的品质,对地层无任何伤害等优点。目前,辽河油田通常采用的清蜡方式是热清蜡和化学清蜡。前者作用周期短,后者注入的化学剂会造成地层污染。相比较而言,微生物清防蜡技术成为首选技术。微生物清防蜡技术是利用解烃菌降解石蜡等长链烷烃的作用,或利用微生物表面活性剂清洗井筒原油,从而达到清蜡的目的。本文简要介绍油井结蜡的成因与微生物清防蜡技术的机理与优点,以欧31块油藏特征(地质特征、原油物性、地层水特征与地层温度压力)为基础,研究辽河油田钻采院获得的一株解烃菌(红球菌Lj1-3),得出该解烃菌具有很好的清防蜡效果,并能降低欧利坨子油井原油的凝固点的结论;研究南开大学石油微生物室从大港油田污水中筛选得到一株产脂肽高表面活性剂的菌种(芽孢杆菌LHX3),得出该生物表面活性剂可耐高温、高盐、高钙离子,pH适应范围为4—12,对高粘原油有增溶、脱附、降粘作用,对高蜡原油有乳化分散作用的结论;将解烃的红与产脂肽类生物表面活性剂的芽孢杆菌LHX3按照7:3的比例复配,在室内研究并验证其解烃和降凝机理,以及其产生的表面活性剂的情况,培养并大量繁殖后配合一定的表面活性剂等诱导因子一起注入地层,利用微生物的代谢作用,达到控制油井结蜡速度、提高油井产量、最终提高采收率的目的。在欧31块开展的20口油井的微生物控制油井结蜡的现场应用中,成功率100%,可将原热洗周期延长至少三倍以上,并且取得了2389吨的增油效果。由此可以看出,微生物清防蜡技术不但可以降低其它清防蜡措施带来的繁重作业和管理难度,还可以减少成本,并有增油效果,直接增加产值,提高经济效益。更多还原

【Abstract】 The crude oil in Liaohe Oilfield is a typical kind of high wax crude oil, the wax content ranges from 8% to 53%, and the high wax crude oil of which the wax content is more than 30% accounts for more than 77% of the reserves. In the process of crude oil recovery, the temperature declines in the process of crude oil moving from the near wellbore area to the well shaft, resulting in the wax precipitation in crude oil , the wax precipitation gathers in the near wellbore area, cause the well shaft blocked or the tube pillar jammed, the problem that the wax precipitat in oil well is serious, oil production declines gradually, and the cost of washing well is much. The implementation of wax-proofing and deparaffining in wax precipitation well is a improtant mean to ensure high wax well normal production.The means of paraffine prevention and removal in oil well include mechanical method, oil pipe lining and coating paraffin method,wax anti-magnetic method, chemical agents method and micro-organisms method, in which micro-organisms methods has the advantages of simple construction, low operating costs, long fuction cycle, disaffect the quality of oil, without any harm to the formation, and so on. At present, the Liaohe Oilfield usually use hot treatment and chemical method. The former has a short function cycle, the latter which inject the chemical agents may cause pollution. Comparatively speaking, micro-organisms methods become the preferred technology.The microorganism paraffine prevention and removal technology makes use of the fuction of the hydrocarbon degradation bacteria degrading long-chain alkanes such as paraffin, or uses microbial surfactants washing the crude oil sticking to well shaft, so as to deparaffin. This paper introduces the causes of paraffin deposit in oil well, the mechanism and advantages of microbial paraffine prevention and removal technology, on the basis of the characteristics of Ou 31 reservoirs (geological features, physical properties of crude oil, formation water characteristics and formation temperature and pressure), research on a hydrocarbon degradation bacteria (Rhodococcus Lj1-3)obtained from Liaohe Oilfield Drilling Institute, the result of the research is that the bacteria has good paraffine prevention and removal effect, and it can decline the freezing point; study the bacteria(Bacillus LHX3) which produce lipopeptide biosurfactant screening from Dagang Oilfield sewage in Nankai University Petroleum microbiology laboratory, it can resist high temperature, high salt, high calcium ion, pH rangs from 4 to 12, and it has the capacity of solution,desorption,viscosity break of high viscosity crude oil and dispersed emulsion of high wax crude oil;The compound experiment was processed in proportion with 7:3 of the two strains, to study and verify the mechanism of hydrocarbon degrading and pour point depressing, to confirm the characteristic of the surfactant. The strains after culture and induction factor, such as surfactant, were injected into formation, with the mechanism of the strains; we can achieve the purpose of controlling the speed of wax deposit in oil well, improving the oil output, and enhancing oil recovery finally.The two strains were applied in 20 oil wells of Ou31 field test for controlling the speed of wax deposit in oil well, the success was 100%. The hot-washing cycle had been prolonged for more than 3 times, and the output of oil well increased by 2389t. it can be seen that micro-organisms wax-proofing and deparaffining technology can not only reduce the difficult of other technologys with heavy operation and management , but also can reduce costs and increase oil production, increase output and economic efficiency dircetly.更多还原