Commingled producing well production split method and its application in Daniudi Gasfield

The historical production profile testing data of commingled gas producing wells in the Daniudi Gasfield varies greatly, so the conventional production split method is not applicable. In addition, a great number of untested wells are in urgent need of production split. The cumulative production profile method was put forward based on the production performance data of the commingled producing wells in the Daniudi Gasfield to deal with the production split of commingled producing wells. Then, the production split model for commingled gas producing wells was established according to the catastrophe theory. Finally, the production split coefficient of each layer in a commingled producing well was calculated. It is indicated that compared with the production profile testing data, the cumulative production profile method can provide more stable production profile and the calculation variance can be reduced by over 70%. And compared with KH production split method, the catastrophe method is over 50% lower in average error, so it is closer to the stable production profile split result. To sum up, the cumulative production profile method can weaken the influence of production profile testing abnormal on the production split result, and the catastrophe theory is more applicable to the production split calculation of commingled gas producing wells in the Daniudi Gasfield. The research results are conducive to improve the calculation accuracy of dynamic reserves, gas drainage radius and other parameters of each layer in the commingled producing wells of the Daniudi Gasfield, providing technical support for gas field development.