Determination of reasonable test time of periodic injection well in Punan Oilfield

Geological Brigade, No.7 oil production plant, Daqing Oilfield Co., Ltd, Daqing, China

Abstract

There were 232 stratified injection Wells in Bunan Oilfield in 2020, including 69 year-round injection Wells and 163 periodic injection Wells. There are many periodic injection Wells and the pressure recovery is slow after injection. After the test, the pressure fluctuates greatly, and the data cannot be reported outside in time, which affects the water distribution. In 2020, according to our actual statistics, the water injection pressure of 38 Wells had a difference of more than 2MPa from the qualified pressure point of the test data before the test of stratified injection well. The reason of pressure discrepancy is mainly related to periodic water injection. In view of this situation, we conducted an investigation on the cycle injection Wells of the whole mine in 2020. The pressure recovery curve was plotted according to the daily injection volume and the length of periodic injection stop time. At the same time, the method of determining the reasonable testing time of periodic injection well is put forward, which provides scientific basis for determining the testing time of periodic injection well.