多层合采气井产量劈分方法及在延长气田的应用OA

Multilayer commingled production is a common development method for multi-layer gas reservoirs.Reasonable splitting of gas production in each layer is a key factor for fine description of gas reservoirs and single-layer productivity evaluation of gas wells.The existing production splitting methods have some shortcomings and defects.The KH method and the mutation theory are of large errors and poor applicability.The numerical simulation method is complicated and takes a long time.The direct measurement method has high cost and cannot reflect the change of the yield contribution rate of each layer in the production process.In order to improve the accuracy of the production splitting results of multi-layer commingled gas wells,a new production splitting method based on node analysis is established by using the dynamic and static data of gas wells.Considering the constraints of reservoir properties of each layer on production,the grey correlation analysis method and analytic hierarchy process are used to quantitatively evaluate the reservoir properties of each layer.Based on the analysis method of multi-layer commingled production nodes in gas wells,the measured gas production is fitted by modifying the productivity coefficient of each layer and the constrained particle swarm optimization algorithm,and then the gas production and yield contribution rate of each layer are obtained.This method is applied to the Yanchang Gas Field.The results show that the error between the yield contribution rate fitted by this method and the production profile test is smaller,and it can reflect the change of the yield contribution rate of each layer with the production time.This method is suitable for commingled gas wells with abundant production data and no production profile test data,and provides more accurate data for single-layer productivity evaluation of gas wells.