一种采油微生物菌剂的制备研究

发布时间：2018-03-02 19:47

本文选题：微生物采油　切入点：表面活性剂　出处：《西北大学》2014年硕士论文　论文类型：学位论文

【摘要】：微生物采油技术(Microbial Enhanced Oil Recovery, MEOR)是利用微生物的代谢产物和代谢活动改变油藏开采条件,提升油井采收率的三次采油手段。MEOR技术因其低能耗、环保、可持续的优势在国外得到长期的发展,但由于其机制复杂,该领域的研究仍有广阔的空间。随着国内油田对提高采收率的需求日益迫切,发展自主知识产权的微生物采油技术对打破国外技术垄断、提高原油产量具有重要的战略意义。本文主要通过多轮筛选得到MEOR潜力较大的细菌和酵母,初步优化了其产表面活性剂的发酵条件和培养基,实施了工业化发酵试验生产出20m3的发酵液,最终进行了油井现场驱油的尝试。完成的主要工作有：从陕北油田某区块多个油井的油水样中富集、分离出细菌和酵母等微生物；通过形态观察和生理生化特点初步确定种类,针对不同类别菌株设计筛选培养基,筛选出能乳化原油并能大量产气的假单胞菌、产表面活性剂性能突出的芽孢杆菌和高效降解长链烷烃的酵母；通过平皿排油圈法、毛细管法衡量所得三类菌株生产表面活性剂相对产量,利用单因素单水平实验确定了产表活培养基最适的碳源、氮源和生长因子,再通过正交试验对发酵培养基配方进一步优化；使用5L发酵罐进行小试研究,确定各菌株发酵过程中菌体量、表活产量、pH等参数的动力曲线,为大规模发酵生产提供参考；利用容量10m3的发酵罐生产了20m3微生物趋油菌剂,随后将菌剂运送到采油现场进行趋油施工,对原油采收率进行观测以评估菌剂的实际效果。实验结果为：筛选出了一株假单胞菌P1、芽孢杆菌B1和酵母Y1；假单胞菌P1、芽孢杆菌B1和酵母菌Y1产生的不同表面活性剂均能显著降低水的表面张力,乳化试验和浸油试验证实了表活培养物从砂岩介质释放残余油的功效；P1和Y1降解长链烷烃的能力较强,固体石蜡的降解率分别为9.1%和25.4%；史氏发酵管培养表明P1以蔗糖为碳源产气迅速,具备增加油藏压力的潜力；优化后的假单胞产表活培养基使用植物油和蔗糖为碳源,缩减了发酵原料的成本；芽孢菌产表活培养基的优化,得到了以更廉价易得的碳源、氮源和生长因子为组分的配方,使大规模发酵生产的原料成本得以降低；通过小试和大规模发酵的实践,初步总结出一次投料发酵生产表活的工艺流程；油田试验中,混合微生物菌剂以水驱的方式作用油层,使8口井中的6口实现了不同程度的增产,累计增油303.46t。
[Abstract]:Microbial Enhanced Oil recovery (MEORO) is a kind of tertiary oil recovery technology, which uses microbial metabolites and metabolic activities to change reservoir production conditions and enhance oil recovery efficiency because of its low energy consumption and environmental protection. The sustainable advantage has been developed for a long time abroad, but because of its complex mechanism, there is still wide space for research in this field. The development of microbial oil recovery technology with independent intellectual property rights is of great strategic significance in breaking the foreign technological monopoly and increasing crude oil production. In this paper, bacteria and yeast with great potential of MEOR are obtained through multiple rounds of screening. The fermentation conditions and medium for surfactant production were preliminarily optimized, and 20 m3 fermentation broth was produced by industrial fermentation experiment. Finally, the oil well field oil displacement was attempted. The main works accomplished include: enriching and separating bacteria, yeast and other microbes from oil and water samples from many wells in a certain block of North Shaanxi Oilfield; preliminarily determining the types of microbes through morphological observation and physiological and biochemical characteristics. A screening medium was designed for different strains to screen out Pseudomonas that can emulsify crude oil and produce large amounts of gas, Bacillus sp. with outstanding surfactant production and yeast that can efficiently degrade long chain alkanes. The relative yield of surfactant was measured by capillary method. The optimum carbon source, nitrogen source and growth factor were determined by single factor and single level experiment. The fermentation medium formula was further optimized by orthogonal test, and the dynamic curves of the parameters such as biomass quantity, viable yield and pH were determined by using 5L fermenter to provide reference for large-scale fermentation. A 20m3 microbial oil-trap was produced in a fermenter with a capacity of 10m3, and then the microbial agent was transported to the oil recovery site for oil trap construction. The oil recovery was observed to evaluate the actual effect of the microbial agent. The results were as follows: a strain of Pseudomonas P1, Bacillus sp. B1 and yeast Y1 was screened, and the surface tension of water was significantly reduced by different surfactants produced by Pseudomonas P1, Bacillus sp. B1 and yeast Y1. The emulsification test and oil leaching test proved that the surface active culture could release residual oil from sandstone medium and the ability of P1 and Y1 to degrade long chain alkanes was stronger. The degradation rates of solid paraffin wax were 9.1% and 25.4, respectively. The results showed that P1 produced gas rapidly with sucrose as carbon source, which had the potential to increase reservoir pressure, and the optimized pseudomonas apparent living medium used vegetable oil and sucrose as carbon source. The cost of fermentation raw materials was reduced, and the optimum medium for the production of Bacillus sp. was optimized to obtain the formula with cheaper and easier carbon source, nitrogen source and growth factor, so that the cost of raw materials for large-scale fermentation production could be reduced. Through the practice of small scale test and large scale fermentation, the process flow of one feed fermentation production surface was preliminarily summed up, and the mixed microbial bacteria agent acted on the reservoir in the oil field test in the way of water drive. Six of the 8 wells have achieved different degree of production increase, and the accumulative oil increase is 303.46 t.
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TE357.9

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