微生物降解稠油及提高采收率实验研究

EXPERIMENTS ON HEAVING OIL DEGRADATION AND ENHANCING OIL RECOVERY BY MICROBIAL TREATMENTS

微生物采油技术以其成本低、无污染、经济效益好的优势 ,日渐成为一项重要的三次采油技术。该技术的主要机理就是利用微生物降解原油的重质组分 ,降低原油粘度和凝固点 ,以达到改善原油物化性质的目的。笔者从原油、油田污水和海水中共分离、选育出能降解沥青质 ,能耐温达 80℃、矿化度 30 0 0 0 0 mg/ L的微生物菌种及组合。并以其对青海、胜利、辽河等油田原油进行了实验研究 ,讨论了能有效降解原油中沥青质的兼性菌的选育、降解效果以及采油过程中的现场应用。根据实验 ,所选育的兼性菌组合对青海原油处理 2 4h后 ,其沥青质可降低 2 0 %。现场试验显示 ,生产井注入菌液 2 0 d后 ,3个月内的日均产量提高了 9% ,油井的热洗周期延长了 2 .

MEOR,with the advantage of low cost, no pollution and good economic benefit,is going to be one of the important techniques for enhancing oil recovery. The authors have selected and cultured a series of bacteria from crude oil, oil polluted water and sea water which they can decompose gum & asphaitenes of oil,increase light hydrocarbon components,endurance 80℃ and 300000mg/L salinity. The microbial cultures and selection methods were discussed and the bacteria treatments were made on the crude oil from Shengli, Liaohe and Qinghai in the laboratories and in the Qinghai Oil Field. After 24 hours treatments by bacteria group,the asphaltenes in Qinghai oil decreased 20%. Results from field tests indicated that after 20 days treatments by the bacteria group,the average daily output increased about 9% and well hot wash period extended 21 times.