提高原油微生物气化技术反应效率实验研究

Experimental Study on Improving Reaction Efficiency of Microbial Gasification of Crude Oil

我国内陆油田经水驱、化学驱和三次采油等开发阶段后,仍有40%以上的原油地质储量滞留在地下,将这些剩余油通过微生物厌氧降解转化为甲烷,以天然气形式进行开采的新开发思路受到关注。影响原油微生物气化反应效率的关键是微生物对原油组分的摄取利用和降解能力。通过添加调控剂的方式促进C_(12)~C_(30)长链烷烃和多环芳烃在水相中的含量,促使微生物优先降解原油中原本较难利用的组分。添加调控剂后原油流动性和亲水性增强,发酵液中出现含水油膜,微生物与含水油膜的广泛接触增加了原油烃组分的摄取效率。通过控制培养体系中电子受体浓度和配比的方法,保持了原油组分厌氧降解的持续性。经过12个月的连续培养,原油的主碳峰向轻组分移动,由空白对照的C_(23)降低为C_(15)~C_(17),原油ΣC_(21)/ΣC_(22)值平均增加15.2%;微生物降解后芳烃含量平均减少28.6%,沥青质含量平均减少49.2%,12个月累计产气275m L,甲烷含量为72.731%,原油微生物气化产气效率显著提升。

After inland oilfields in China experienced development stage of water flooding,chemical flooding and tertiary oil recovery,more than 40% of original oil in place is still underground.New development method was proposed： the remaining oil may be transformed to methane by microbial anaerobic degradation,and be developed as natural gas.The key problems affecting reaction efficiency of microbial gasification of crude oil are the capability of intake of components of the crude oil and the biodegradation of the microbe.Adding regulat-ing substance may make the content of C12~C30 alkanes and polyaromatic hydrocarbon in the water increase,which promotes the degradation of the component of crude oil being more difficult to use by the microbe first.After adding the regulating substance,liquidity and hydrophilicity of the crude oil were enhanced,water-bearing oil film appears in the fermentation broth,and intake efficiency of the hydrocarbon component of the crude oil may be improved by extensive contact between the microbe and water-bearing oil film.Anaerobic biodegradation of the crude oil component may be continued by controlling the ratio and concentration of electron acceptor in the culture system.After 12 months of continuous culture,main carbon peak of the crude oil moved towards the light carbon and reduced to C15~C17 from C23,and ΣC21/ΣC22 of the crude oil increased by 15.2% on average.The content of aromatic hydrocarbons and asphaltene decreased by 28.6% and 49.2%respectively on average after the microbial degradation.Cumulative gas production in 12 months was 275 m L,and methane content was 72.731%.The reaction efficiency of the microbial gasification of crude oil significant-ly increased.