Enhanced use of "specialties" for enhanced oil recovery Microbial oil recovery is expected to dominate the later development of oil fields

The scientific and technical personnel of the Exploration and Development Research Institute of Daqing Oilfield selected several “special special forces” from more than 100 strains cultivated in the past 10 years, and from the end of last year, 10 wells used in the No. 7 plant of the oil extraction plant in the north of the oilfield were used for microbial oil recovery. test. In mid-June this year, only six months later, these "special forces" could easily drive out more than 1,600 tons of crude oil in kilometers underground. What is even more amazing is that two of these dead wells actually returned to "dead" and normal production resumed.

Microbial oil recovery technology is characterized by "short, flat, fast", low cost, no pollution and damage to the environment and strata, simple injection equipment, high input-to-output ratio. In addition, the effect of microbial single-well stimulation test is generally better than measures such as fracturing, acidification and plugging, and hydraulic high-pressure deblocking, and it also has the effect of slowing the waxing speed and prolonging the wax removal cycle. It is very suitable for “three lows”. The exploitation of the oil field.

Once on the achievements, explore for several years. In 2002, the Daqing Oilfield Exploration and Development Research Institute conducted a total of 13 well tests in the Chaoyanggou oil field of the No. 10 Oil Production Plant. After injection of microorganisms, the average water content decreased by 16%, cumulative oil increase was 2138 tons, and the input-output ratio was 1:9. By the end of 2003, the research team conducted a total of 60 wells of microbial throughput in the Chaoyanggou oil field, accumulating 9175 tons of oil. The success of the microbial throughput test showed that the selected strains could grow well under the conditions of the formation and increase the crude oil flow capacity. At the same time, the test also broke the standard that the US Department of Energy's microbiological oil production penetration rate should be more than 50 millidarcy, and expanded the scope of application of this technology.

Later, the Daqing Oilfield Exploration and Development Research Institute implemented a second round of microbiological throughput in 4 wells that were effective in 2002, and also achieved substantially the same oil increase effect as in the first round, indicating that microbiological single-well stimulation can be used as a measure many times. construction.

Based on the success of the microbiological throughput test, researchers have successively completed the microbiological drive field test and achieved good results. The most exciting gains from the trials conducted in the Pubei oilfield were that the microbial drive not only restored the two wells that had been shut down for three years and restored normal production, but also announced that microbial oil recovery technology reduced the flow during waterflooding. Resistance, the extent of oil use increased.

Microbial oil recovery technology has broad application prospects. At present, the research group is conducting research on peripheral oil fields, transitional zones in old areas, and chemically driven reservoirs that are not suitable for chemical flooding technology, so as to make this technology an effective replacement technology for oilfields in the later stages of development.