Research Of Water Control Stable Yield To Multi-layer Water Flooding Reservoir

The structural position of wellblock T belongs to east China sea shelf basin depression, south of the central inversion structionbetween Zhedong depression and xihu depression sag of south central, it’s structure is compression anticline.The whole structure is a north north east big composite anticline, with the characteristics of the east slowly west steep. The region is located in the rise of the main thrust plate.The reservoir has poor continuity. There is mudstone interbed between adjacent reservoir. Ithas strong heterogeneity and the characteristicsof low porosity, low permeability, and high reserves abundance. It belongs to the multilayer commingled production of condensate gas reservoir and a large number of edge water distributed gas reservoir boundary. It has eight production Wells in this gas reservoir block with stable production for two yearsup to December,2013.Because of using depletion development, the production of 8 production Wells have appeared different degree of decline in output,the phenomenon ofbottom hole liquid loading, and because of the lack of bottom well pressure, part of the production wells has seen water.Thesephenomenon caused serious harm to normal production of gas well.But due to the lack of profile test data, because of the unknown dividing coefficient of each small layer in the layer, it can’t make sure that which layer may see the water. From the gas liquid two phase flow theory we can know that, with the decrease of liquid saturation and gas well produced fluid volume, the gas production may greatly reduce. In different small layers,because of the different change of liquid saturation due to physical differences, gas production of each small layer are greatly influenced by small layer fluid saturation.That the gas-liquid permeability and liquid saturation of different small layers at the same time is the important factor of the contribution value to all small effect layer gas production. Because of only considering single factor, traditional stratigraphic coefficient method for calculating the split coefficient absolutely depends on the static reservoir physical parameters (formation absolute permeability and effective thickness of layer), and result in the big error and greatly deviate from the actual situation. In this paper, through the analysis about the present situation of the T gas field production, from production split, it establishesa new production split method which based on gas water phase and gas oil permeability, and on this basis a calculation software is making to calculate the KHK production split coefficient. It makes it more accurate and simple tocalculate the production split coefficient.Using KHK production split method and combining with dynamic data of T gas field production, it can make sure which layer can see the water of every well, predict the time when it can see the waterin danger well layer, calculate the critical production of every well which has bottom water layer, and combined with productivity,critical liquid-carrying flow ratea reasonable production was given.On the basis of the enough understanding of gas reservoir, divide the layer series of development. According to the split coefficient of gas well reservoir, each production layer of the hierarchical system has carried on the fine proration and formulate the stable solution.Combined with reservoir engineering and numerical simulation of the Eclipse software system stable solution are verified. The results show that the layered system development which has certain feasibilityimproves the stable time and field recovery.