TRIAL AND EFFECT ANALYSIS OF CO2 HUFF AND PUFF IN COMPLEX FAULT RESERVOIR

Between 1989-2001, CO2 huff and puff technology has been done in nine wells in Qintong Sag of Subei Oilfield. The effect and affect actors have been introduced to three kinds of reservoirs such as high permeability and high water cut pools, low permeability and low production pools, viscous oil reservoir. In the high permeability and high water cut pools, CO2 huff and puff can depress water cut and improve production, but the problem of corrosion must be take good care of. In the low permeability and low production pools, CO2 huff and puff can improve production but must be solved the problem of secondary pollution. In the viscous oil reservoir, CO2 huff and puff can improve production but must be solved the problem of oil degassing in the hole. Field testing indicate: this technology some characters with width using scope, smaller cost, smaller scale and quicker effect.