The Research On Adaptability Of Well Pattern About Water Injection In Low Permeability Reservoir

Though low-permeability reservoirs have abundant reserves, the development is difficult and the degree of exploitation is low because of its poor natural property. Reasonable well spacing pattern and well network configuration parameters and fracture parameters can be effective in improving the development of low-permeability reservoir effect, therefore, study adaptive form of a well network, choose a reasonable well spacing pattern and the wells network parameters, is one of the key issues of cost-effective development of low permeability reservoir.In this paper based on extensive research to study the identification of well spacing about vertical well network of the water flooding development of low-permeability reservoir, including the critical technological well spacing, critical economic well spacing, the economic optimum well spacing and reasonable well spacing. Adaptive study of five different kinds of well network has been done by numerical simulation method, including the inverted nine-spot rhombus well pattern, a five-point rectangular well pattern, non-linear isometric well pattern, the five-spot well pattern, staggered row of well pattern, the inverted nine-spot well pattern. Using numerical simulation, the reasonable ratio of space between wells and rows in anisotropic low permeability reservoirs were studied as well as the relationship between well network configuration parameters and the fracture parameters. Adaptability about pairs of horizontal wells were studied, including the corresponding wells of parallel networks, parallel staggered wells network and two kinds of "L"-type wells network, then compared development effect of different well patterns and studied effect of fracture parameters on pairs of horizontal well pattern development. Study of adaptability of horizontal-vertical well pattern first of all carried out in combination modes of horizontal-vertical well pattern, and then the relationship between well network configuration parameters and fracture parameters were studied, including the research about the relationship between the direction of the well row , the horizontal well bore and the fracture configuration parameters, at the same time compared development effect of different well patterns for choosing a reasonable form of well pattern and the well pattern parameters.