SU947400A1 - Oil deposit working method - Google Patents

Description

The invention relates to the oil industry, in particular to methods of developing oil fields.

There is a method of developing an oil reservoir by placing a system of production and injection wells on it. Oil is extracted from producing wells, a displacing agent is pumped into injection wells.

The disadvantage of the known method is the monomericity of the filtration flow, which in real heterogeneous, discontinuous formations leads to significant losses of oil in various dead ends, lenses, half-lenses of sandy and impermeable bodies. A well-known method is to develop an oil reservoir, which consists in injecting water through injection wells, extracting oil through exploratory wells followed by transferring the in-production well to the injection well when advancing water at a distance of not less than half the distance between the injection well and the displacement well. .

Not enough ;; lannogo spo, both is neg .. oil recovery

when it is used in a reservoir that is not uniform in permeability due to oil losses in stagnant zones.

The purpose of the invention is to enhance oil recovery of a reservoir that is not uniform in permeability.

This goal is achieved by the fact that in a well-known method of developing an oil reservoir, which consists in pressurizing water through injection wells, extracting oil through production wells and subsequently transferring water injection to the watering production well.

15, when water is propelled to a distance of not less than half the distance between the injection and the watering production wells, the movement of water is determined by the least permeable layer of the formation.

The method is carried out as follows.

The deposit is drilled in a triangular or square grid of wells. WITH

25, using selective or regular principles, dispersedly designate injection wells for injection. Oil is taken from producing wells, into oil pumps.

30 pump agent. According to the geological-physical information of wells, a layered reservoir model is constructed. The moment of achievement: the injected fluid half the distance along the least permeable layer between the production and injection well can be defined in two ways. In the first case, it is determined from the results of modeling the progress of the injected fluid along different layers. In the second case, it is determined by the water-cut of the production well. To do this, the water cut is pre-determined from the flooding state of the current tube stack, at which the least permeable layer is watered half the distance between the production and injection wells. After that, the production well is transferred to the injection agent. From a practical point of view, the transfer of production wells for injection should be discontinued at the moment when the maximum oil production capacity has been reached. Mi | i "Such a principle of transferring production ch1 wells for injection excludes losses of oil in low-permeable layers. Since in real layers filtration. . The flow of the fluids varies widely over speeds,,. .; h will be within wide limits,. jf- ,. the marginal fractions of the agent at which the production of a well is transferred to the injection. In relation to the conditions of oil reservoirs in Western Siberia, the agent's share can vary from 0.2 to 0.9, the bottomhole pressure in injection wells can vary from 250 to 450 cm and in producing wells - from 100 to 250 | g. the proposed development method, injection wells that are transferred under pressure, create additional pressure gradients in the filtration field, which increases the oil recovery rates over time, brings the extraction zone closer to the injection zone, which increases the waterflood coverage and oil recovery, turns filtration flows, in addition to the development of additional oil reserves, which also increases oil recovery and allows the most complete utilization of the drilled well stock, since the spent production wells remain in operation with another Functional purpose. The invention of the method of developing an oil reservoir, which consists in injecting water through injection wells, extracting oil through production wells with subsequent transfer to the watering production well for injecting water as the water moves no less than half the distance between the injection well and the watering production well, distinguished by the fact that, in order to increase the non-uniform permeability of the formation, oil recovery, the water flow is determined by the least permeable reservoir Sources of information taken into account during the examination 1. A. Krylov. and others. Designing the development of oil fields. M., Gostoptekhizdat, 1962, p. 430. 2. The patent of the USA 3120870, cl. 166-9, published. 1964.

Claims (1)

Claim 20 A method of developing an oil reservoir, which consists in pumping water through injection wells, taking oil through production wells, followed by 25 transferring water to the watering production well while pumping water at a distance of at least half the distance between the injection and watering production 3Q wells, which differs from the fact that, in order to increase oil recovery of a heterogeneous permeability of the formation, the progress of water ^g is determined by the least permeable 25 layer of the formation.