Proper Production Allocating Study On Commingling Production For Sand Production Gas Well

When commingling production gas wells produced in unconsolidated sandstone gas reservoir, the difference of producing pressure drop among each layer would cause problems such as sand production and interlayer development imbalance. It has been proposed that five factors should be considered in commingling production gas well production allocation in unconsolidated sandstone gas reservoir, which are production layer capacity, production layer sand production, pipeline erosion, shaft sand settling and liquid loading. The Mohr-Coulomb rule has been chosen as the failure criterion to calculate the sand production pressure drop of unconsolidated sandstone reservoir and on this basis the mathematic model of critical sand producing pressure drop has been build. The affection of shale content and water saturation for sand production has been considered in the modification of critical sand producing model. The modified model has improved the accuracy of13.9%. Using the binomial productivity calculate model as the theoretical foundation, the mathematical formula to calculate each layer’s productivity and production has been deduced and on this basis the production allocating model of multiple completion gas wells has been build. After comprehensive analysis of the five factors that limit the production, an allocating production method to determine the multiple completion gas wells’production has been proposed. Practice has proved this method to be simple and efficient. The research contents of this paper can provide theoretical foundation and applied method for production allocating of multiple completion gas wells in unconsolidated sandstone reservoir. The method can also be used as a reference for production allocating of wells of other kinds. It brings the research of production allocating of multiple completion and sand-producing wells into a new level.