关键词: 自生CO2, 表面活性剂, 复合吞吐, 操作工艺参数, 数值模拟

Abstract:

In-situ-generated CO2 huff-puff is a new technology to improve recovery in the low permeability fault-block reservoir.
It is not only able to take advantage of the mechanisms of miscible/immiscible CO2 flooding，but also is more suitable
for the reservoir without enough CO2 source and corrosion resistant pipe-string. This paper explores and investigates the optimization
method of the operating parameters by means of the chemical flooding and thermal numerical model. Taking a low
permeability fault-block reservoir as an example，the single-well radial model is set up. According to experiment results of the
autogenic CO2 and the surfactant flooding，based on the parameter calculation of the PVT，autogenic CO2，surfactant flooding
and history matching，the operating parameters are determined，including the volume and concentration of blowing agent，
injection rate，shut-in time，liquid withdrawal rate. The results show that the optimal value of the volume，concentration，and
liquid withdrawal rate are 200 t to 250 t，3%～5%，7 m3/d，respectively. The effect of the compound huff-puff will be improved
by increasing the inject rate and shut-in time. The study will be a great significance for the application and promotion of the
in-situ-generated CO2 compound surfactant huff-puff in the low permeability fault-block reservoir.

Key words: in-situ-generated CO2, surfactant, compound huff-puff, operating parameter, numerical simulation