The Application of Microbial Enhanced Oil Recovery in Daqing Oilfields

Abstract To seek an effective oil recovery approach, Brevibacillus brevis and Bacillus cereus were screened and applied in a Microbial Enhanced Oil Recovery (MEOR) process to recover oil from Daqing low permeability oilfield where have many disadvantageous conditions. Microbial huff and puff trials have been conducted in 93 wells with accumulative incremental oil amounting to 100878 barrels and average of 1081.9 barrels for one individual well. The effective ratio was 74.2%. Microbial flooding field test with 2 injectors and 10 producers was carried out.7 out of 10 wells showed effective results, with 105995 barrels of accumulative incremental oil. In October 2009, expanding field test with 9 injectors and 24 producers was carried out in this block. Now 15 wells have shown good effect with oil production increased by 41.6%. The analysis showed that wells with good injection-production relationship, differences of layers and well deliverability are main effects to the results of microbial huff and puff. The microbial flooding results showed that wells along the main channel sand and developed fracture zones had a better response.