RU2418155C1 - Method of system cyclic development of oil deposit at late stage - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: method involves pumping of displacement agent via injection wells, oil extraction via production wells, cyclic measurement of pumping modes of displacement agent and oil extraction via wells, analysis of field-geologic data on operation of wells, address control of development in isolated zones. According to invention, wells with row drilling mesh is chosen. For the first operating cycle the zones of injection wells are defined, which are isolated from other zones with rows of injection wells located on both sides of injection wells. Middle row of production wells is taken, which are located approximately at equal distance from rows of injection wells. To rows of injection wells the agent is pumped at pumping pressure, and forced pumping-out is performed from middle row of production wells with volume which is by 10-15% higher than that during pumping-out in other rows. As per analysis results of geologic production data from production wells, quantity, rate and water blockage and/or gas-cutting of oil, the decision on transition to the second cycle is taken with change of development zones perpendicular and similar to initial zones. At that, pumping modes of displacement agent to injection wells and oil extraction from production wells are chosen similar to the first cycle. As per analysis results the decisions on transition to the first cycle are taken; after that, cycles alternate.

EFFECT: method is simplified and costs for implementation of method are reduced without decreasing the efficiency of system cyclic development of oil deposit at late stage.

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Description

The invention relates to the oil and gas industry and can be used in the development of oil deposits at a late stage.

The well-known "Method for the development of hydrocarbon deposits" (patent RU 2154158, IPC 8 E21B 43/20, published in Bulletin No. 22 of 08/10/2000), including determining the magnitude of the residual reserves of hydrocarbons, building maps of the distribution of residual reserves of hydrocarbons and depending on the distribution of the residual hydrocarbon reserves, measures to regulate the development system, characterized in that the determination of the residual hydrocarbon reserves is carried out using three-dimensional mathematical models, post Development of the maps for the distribution of residual hydrocarbon reserves is carried out at the end of development under the existing development system, and measures to regulate the development system are carried out by forming targeted foci of additional development in the areas where residual reserves are located, which cannot be extracted under the existing development system, as independent elements of the development system formed by additional drilling and / or input from idle and / or from other horizons of injection and / or production wells n, put into operation in the "self-titled" formation.

The disadvantage of this method is the low profitability of its application, due to the fact that the most significant development parameters are calculated conditionally using hydrodynamic mathematical models, while real parameters characterizing the behavior of the reservoir under various conditions of its hydrodynamic regime and really folding filtration fields during the development of the reservoir are not taken into account.

The closest in technical essence is the "Method of systematic cyclic development of an oil reservoir at a late stage" (patent RU 2209947, IPC 8 E21B 43/16, published in bulletin No. 22 of 08/10/2003), including injection of the displacing agent through one or several injection wells, oil recovery through one or several production wells, analysis of geological and production data on the operation of each of the wells, taking into account the entire history of the development of this reservoir, isolation from the development history of spontaneous - unplanned changes in the hydrodynamic regime the operation of all wells and the response of the reservoir to these spontaneous changes in the hydrodynamic regime by changes in the performance of producing wells, the allocation of zones of residual oil reserves by the response of the reservoir, and by the parameters of the response, namely the amount, rate and watering and / or aeration of oil recovered from the producing wells after a spontaneous change in the hydrodynamic regime, determining the amount of residual oil reserves, deciding on the profitability of the subsequent development of the reservoir and, in the case of profitability shoes of the reservoir as a whole or of its individual allocated response zones, targeted regulation of the development system in the allocated response zones, taking into account the obtained response results, while spontaneous shutdowns of injection and / or production wells due to their unforeseen repairs are referred to spontaneous - unplanned changes in the hydrodynamic mode of operation of the wells and / or accidents and / or flooding, and spontaneous - unplanned changes in the hydrodynamic regime include violations of periods of the planned cycle the well operating mode during the development of the reservoir, while additional injection and / or production wells are drilled in the allocated zones, and in the allocated zones, primary primary directions of the filtering flows of the displacing agent into the deposits are revealed, for example, using labeled liquids, after which the filtration flows are set new directions, while new directions for filtration flows are set, for example, normal with respect to the primary directions.

The disadvantages of this method are:

- firstly, the high cost of its implementation, due to the fact that in the selected areas drill additional injection and / or production wells;

- secondly, the complexity of the method, due to the fact that it is constantly necessary to vary the duration of the cycles with increasing this duration from cycle to cycle. The rate of injection of the displacing agent also varies. In addition, in neighboring areas, all variations of the cyclic mode are carried out in antiphase. For example, with an in-line development system, the cyclic mode is carried out by the "traveling" wave method, when this pressure wave is created in a series of injection wells with a length corresponding to 5-10 wells, and a pressure wave of the same length but with the opposite phase is propagated in the opposite row. The phases of the oscillations during one cycle make the phases of the discharge pressure opposite, and during the other cycle, coincide with them.

The objective of the invention is to simplify the implementation of the method and reduce the cost of implementing the method without reducing the effectiveness of the systemic cyclic development of oil deposits at a late stage.

The problem is solved by a method of systematic cyclic development of an oil reservoir at a late stage, including injection of a displacing agent through injection wells, oil recovery through production wells, a cyclic change in the modes of injection of a displacing agent and oil selection through wells, analysis of geological and field data on the operation of wells, address regulation development systems in dedicated areas.

The new one is that wells with a straight-line drilling grid are selected, zones of injection wells are distinguished for the first cycle of operation, cut off from other zones by rows of injection wells located on both sides of injection wells, an average row of production wells located at approximately the same distance from the rows of injection wells is distinguished , a displacing agent is pumped into the rows of injection wells, and forced selection with a volume of 10-15% higher volume is performed from the middle row of production wells than during selection in other rows, according to the results of the analysis of geological production data from production wells (the amount, pace and watering and / or aeration of oil), a decision is made to switch to the second cycle with changing the development zones perpendicular and similar to the initial zones, while the modes of pumping the displacing agent into injection wells and selection oil from producing wells is selected similarly to the first cycle, according to the results of the analysis, decisions are made to switch to the first cycle, after which the cycles alternate.

Figure 1 shows the first cycle of the method of systemic cyclic development of oil deposits at a late stage.

Figure 2 shows the second cycle of the method of systemic cyclic development of oil deposits at a late stage.

The essence of the method is as follows.

The displacing agent is injected through one or more injection wells. Oil recovery is carried out through one or more producing wells. At the same time, the analysis of geological and field data on the operation of each of the wells is carried out. The amount of residual oil reserves in the deposits is determined and the development system is regulated. Select wells with in-line mesh drilling (see figure 1 and 2).

First carry out the first cycle (see figure 1) of the cyclic development of an oil reservoir at a late stage. For this purpose, zones of injection wells 1 and 1 ′ are distinguished, cut off from other zones by rows of injection wells 2 and 2 ′ located on both sides of injection wells 1 and 1 ′, respectively. Then allocate the middle row of production wells 3 located at approximately equal distance a and b from the rows of injection wells 1 and 1 ′. A displacing agent (for example, wastewater) is pumped into the rows of injection wells 1 and 1 ′, while the displacing agent is not pumped into other rows of injection wells 2 and 2 ′. From the middle row of producing wells 3, where a contraction zone is formed, forced selection of oil is performed with a volume 10-15% higher than the volume taken during the other rows of producing wells 5 ... 5 ⁿ , of which the oil is extracted in the previous mode. According to the results of the analysis of geological data from the rows of producing wells 3; 5 ... 5 ⁿ (the amount, pace and watering and / or aeration of oil), for example, when the water cut of the produced oil exceeds the economically profitable value in any of the series of wells 5 ... 5 ⁿ , they decide to move to the second cycle with a change in the development zones perpendicular and similar to the original zones, while the modes of injection of the displacing agent into the injection wells and the selection of oil from the producing wells are chosen similarly to the first cycle, that is, as follows.

In the second cycle (see figure 2) of the cyclic development of an oil reservoir at a late stage, zones of injection wells are distinguished, cut off from other zones by rows of injection wells 2 and 2 ′ located on both sides of the injection wells. After that, the middle row of producing wells 3 ′, located at approximately equal distance c and d from the rows of injection wells 2 and 2 ′, is again distinguished.

A displacing agent (for example, wastewater) is pumped into the rows of injection wells 2 and 2 ′, while the displacing agent is not pumped into other rows of injection wells 1 and 1 ′. From the middle row of production wells 3 ′, where a contraction zone is formed, forced selection of oil is performed with a volume 10-15% higher than the volume taken during the other rows of production wells 5 ... 5 ⁿ , of which the oil is extracted in the previous mode. According to the results of the analysis of geological data from production wells 3 ′; 5 ... 5 ⁿ (the amount, rate and watering and / or carbonation of oil), for example, when the water cut of the produced oil exceeds the economically profitable value, they decide to switch to the first cycle, as described above, after which the cycles alternate.

The proposed method is simple to use, since the systematic cyclic development of an oil reservoir at a late stage is carried out in two cycles, each of which has its own contraction zone with their subsequent alternation, and the reduction in the cost of its implementation is that there is no need to drill additional injection and / or production wells and at the same time, the efficiency of the systematic cyclic development of an oil reservoir at a late stage does not decrease.

Claims (1)

A method for systematic cyclic development of an oil reservoir at a late stage, including pumping a displacing agent through injection wells, extracting oil through production wells, cyclic changing the modes of pumping a displacing agent and oil selection through wells, analysis of geological and field data on the operation of the wells, targeted regulation of the development system in selected zones, characterized in that wells with a straight-line grid of drilling are selected, for the first cycle of work, zones of injection wells are cut off from other of the middle zones of injection wells located on both sides of the injection wells, the middle row of production wells is located at approximately equal distance from the rows of injection wells, a displacing agent is pumped into the rows of injection wells, and forced selection is made from the middle row of production wells with a volume of 10 -15% higher volume than when selected in other rows, according to the analysis of geological production data from producing wells, the amount, rate and watering and / or aeration of oil, take p the decision to switch to the second cycle with changing the development zones perpendicular and similar to the initial zones, while the modes of pumping the displacing agent into the injection wells and the selection of oil from the producing wells are chosen similarly to the first cycle, according to the results of the analysis, decisions are made to switch to the first cycle, after which the cycles alternate.

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