The determination of the injection-production well spacing with the consideration of the start-up pressure gradient

It is one of the main research contents for the effective development of the low permeability reservoir how to determine the reasonable injection-production well spacing owing to the start-up pressure gradient in the process of the flowing through porous media, According to the theory of flowing through porous media for the production-one source-one convergence point, the calculation formula for the maximum start-up pressure gradient in the midpoint of the channel line in the flooding unit is acquired. Integrating the relation between the start-up pressure gradient and the permeability, the determination method of the reasonable injection-production well spacing for the low permeability reservoir is established and the theoretical plate for the reasonable injection-production well spacing on the condition of different permeability and injection-production pressure drawdown is obtained. The case application reveals that this method is simple and practical, the analytical results are basically identical with the actual situation in oil field.