RU2548459C1 - Method of cluster drain and disposal of associated water - Google Patents

Abstract

FIELD: oil-and-gas industry.SUBSTANCE: this process comprises measurement of injection well capacity, feed of products of one or several production wells for preliminary water disposal. Measured are density of green oil and gas, green oil water content are measured in the well. Here said products are divided into partially dewatered oil, gas and water. Partially dewatered oil and gas are fed in gathering main. Disposed water is fed into injection well. Compatibility of disposed water with water of seam wherefrom pumping from injection well is made is defined. If threes are compatible, injection well is equipped with the device to create water pressure sufficient for water injection into seam, for example, with electrically-driven rotary pump. Said device allows varying of feed capacity by frequency-controlled drive for said pump. It is set to minimum feed to define the compliance of disposed water quality with the seam geological properties. At poor water quality, it is directed to gathering main or, at sufficient quality, it is forced into injection well. Disposed water amount is defined. Then, device feed capacity is increased either continuously or in stepwise manner to create water pressure. It is increased unless disposed water quality satisfied the seam geological properties.EFFECT: higher process efficiency.3 cl, 1 dwg, 1 ex

Description

The claimed invention relates to the field of equipment for the oil industry, and in particular to methods of cluster discharge and utilization of produced water in oil fields of a late stage of development, and may find application in sealed systems for the production and collection of oil wells.

A known method of cluster discharge and disposal of produced water, including supplying the products of one or more producing wells to a well for preliminary water discharge, measuring the amount of crude oil and gas, as well as the water cut of crude oil, oil and water densities entering the well for preliminary water discharge , dividing the products therein into partially dehydrated oil, gas and water, sending partially dehydrated oil and gas to a collection manifold, supplying discharged water to an injection well or water conduit described in the operation of the device according to the patent for utility model No. 96176, IPC ЕВВ 43/38, Publ. 07/20/2010.

The disadvantage of this method is the lack of efficiency, due to the fact that the quality of the water supplied to the injection well or water conduit is poorly controlled, and its quantity is constant.

The closest technical solution for the combination of essential features to the claimed invention and selected as a prototype is a method of cluster discharge and utilization of produced water, including measuring the injectivity of an injection well, supplying one or more production wells to a well for preliminary water discharge, measuring the density of the amount of crude oil and gas, as well as water cut of crude oil, oil and water densities entering the well for preliminary water discharge, division in it products for partially dehydrated oil, gas and water, the direction of partially dehydrated oil and gas to the collection manifold, the supply of discharged water to the injection well, in which the pressure of the water pumped into the injection well can change / utility model patent No. 102056, IPC Е21В 43/20 ; Publ. 02/10/2011 /.

The disadvantage of this method is the lack of efficiency, due to the fact that the quality of the water supplied to the injection well is poorly controlled, and its quantity is constant.

The aim of the invention is to increase efficiency.

This goal is achieved by the fact that in the inventive method of cluster discharge and disposal of produced water, including measuring the injectivity of the injection well, supplying the production of one or more producing wells to the well for preliminary water discharge, measuring the amount of crude oil and gas, as well as the water cut of crude oil, the density of oil and water entering the well for preliminary water discharge, dividing the products into partially dehydrated oil, gas and water, sending partially dehydrated oil and gas to the teams the collector, the discharge of discharged water into the injection well, according to the invention, the compatibility of the discharged water with the water of the formation to be injected from the injection well is determined; when the water is compatible, the injection well is equipped with a device to create sufficient water pressure to pump water into the formation, configured to change supply and installed at the minimum supply, determine the compliance of the quality of the discharged water with the geological conditions of the reservoir, with unsatisfactory quality of the discharge When it is supplied with water, it is sent to a collection collector, with satisfactory quality of the water discharged, it is sent to the injection well, the amount of water discharged from the injection well is measured, then, with a selected constant or variable step, the flow rate of the device for creating water pressure is increased, and this increase is made until as long as the quality of the discharged water satisfies the geological conditions of the reservoir. In addition, in cases of periodic shutdown and / or inclusion of oil wells in the cluster, the pressure of the discharged water at the outlet of the well can be created for preliminary discharge of water higher than in the collection manifold. In addition, in cases of a high gas content in crude oil or the possibility of gas plugs getting caught, degassing of the discharged water can be carried out, for example, by oscillations.

As a device for creating a water pressure sufficient for injection into the reservoir, a change-over pump, or a horizontal pumping unit, or a pit with an electric centrifugal pump suspended in it, can be used.

As a device for creating a water pressure, made with the possibility of changing the supply, either a variable frequency drive or a replacement of the pump with a pump with a different supply, or the removal of part of the incoming liquid into the collection manifold, can be used.

Determining the compatibility of the discharged water with the water of the formation into which it is injected from the injection well allows excluding the injection of incompatible water into the formation and avoiding its clogging, which improves efficiency.

Equipping, when the water of the injection well is compatible, a device to create sufficient water pressure to pump water into the formation, for example, an electric reversing pump, allows water to be injected into the formation without using a reservoir pressure maintenance system, thereby increasing efficiency.

The implementation of the device to create a water pressure with the ability to change the flow, for example, a variable frequency drive for an electric centrifugal pump - "changeling", allows you to change the amount of water injected into the reservoir, which improves efficiency.

Determining the compliance of the quality of the discharged water with the geological conditions of the formation avoids the injection of low-quality water into the formation, which ensures increased efficiency.

Setting the minimum supply of the device to create water pressure allows you to conduct research in the entire supply range, which increases efficiency.

The direction with unsatisfactory quality of the discharged water into the collection header allows to avoid contamination of the reservoir, which ensures increased efficiency.

The direction with satisfactory quality of the discharged water into the injection well allows the injection of high-quality water, which ensures increased efficiency.

Measurement of the amount of discharged water coming from the injection well allows the implementation of measures for rational subsoil use, which ensures increased efficiency.

The choice of a constant or variable step to increase the flow rate allows to increase the information content of the injection, which provides an increase in efficiency.

Increasing the supply of the device for creating water pressure at the selected step allows to reduce energy consumption, which provides increased efficiency.

Performing an increase in the supply of the device to create water pressure until the quality of the discharged water satisfies the geological conditions of the formation, allows to reduce energy consumption and increase the amount of injected water, which ensures increased efficiency.

The creation of the pressure of the discharged water at the exit from the well for preliminary discharge of water is higher than in the collection manifold, which in some cases reduces the possibility of emergencies, which ensures increased efficiency.

The degassing of discharged water, for example, by oscillating elements of a downhole water discharge installation (to create waves) to separate dissolved gas from water, improves water quality, which improves efficiency.

The inventive method of cluster discharge and disposal of produced water is carried out by the following sequence of operations;

1) metering injectivity wells;

2) determining the compatibility of discharged water with the water of the formation into which it is injected from the injection well;

3) when water is compatible, equipping the injection well with a device to create a water pressure sufficient to pump water into the formation, for example, with an electric reversing pump;

4) the implementation of the device to create a water pressure with the ability to change the flow, for example, a variable frequency drive for an electric centrifugal pump - "changeling";

5) setting the minimum supply to the device to create water pressure, which before the start of the flow of water to it works in the "idle" mode;

6) supplying the products of one or more producing wells to the well for preliminary discharge of water;

7) measuring the densities of the amount of crude oil and gas, as well as the water cut of crude oil, the densities of oil and water entering the well for preliminary discharge of water;

8) division in the well for preliminary discharge of water of the incoming products into partially dehydrated oil, gas and water;

9) direction from the well for the preliminary discharge of water of partially dehydrated oil and gas into the collection manifold;

10) determining the conformity of the quality of the discharged water at the exit from the well for preliminary discharging of water to the geological conditions of the formation into which it is planned to be injected;

11) supply with unsatisfactory quality of discharged water at the exit from the well for preliminary discharge of discharged water into a collection header;

12) supply with satisfactory quality of discharged water at the exit of the well for preliminary discharge of water into the injection well;

13) measuring the amount of discharged water coming from the injection well;

14) work in this mode for a certain period of time, for example a week, with periodic, for example 2 times a day, quality control of the discharged water;

15) the choice of a constant or variable step to increase the flow of the device to create water pressure;

16) increasing the supply of the device to create water pressure at the selected step;

17) repetition of operations 6) ... 14);

18) repetition of operations 16) and 17) until the quality of the discharged water satisfies the geological conditions of the formation.

19) the creation in cases of periodic shutdown and / or inclusion of oil wells of the bush of pressure of the discharged water at the exit from the well for preliminary discharge of water is higher than in the collection manifold (this operation is additionally included in operation 11)).

20) the implementation in cases of a high gas content in crude oil or the possibility of gas plugs entering the degassing of discharged water, for example, by vibrating elements of a downhole water discharge installation (to create waves) to separate dissolved gas (this operation is additionally included in operation 10)).

Example

One of the possible embodiments of the device for implementing the inventive method of cluster discharge and disposal of produced water is shown in figure 1.

A production supply pipe 2, a partially dehydrated oil and gas drain pipe 3 and a water drain pipe 4 are connected to the downstream water pre-discharge installation 1. The water drain pipe 4 includes a device for determining the quality of water 5 and a valve 6. A pipe for the drain of partially dehydrated oil and gas 3 connected to the drainage pipe 4 bypass line 7 with a valve 8. The drainage pipe 4 is connected to the injection well 9 through a string of tubing 10, On the column tubing 's suspended pipes 10 pump- "shifter" column 11. The outlet tubing 10 is located below the packer 12.

This device, carrying out the inventive method of cluster discharge and disposal of produced water, works as follows.

In the borehole installation of preliminary water discharge 1 through the pipeline supplying products 2 enters the production of oil wells - oil and gas mixture. At the pump “shifter” 11, the minimum flow rate is set (for example, 35 Hz with a frequency range of 35-60 Hz - the flow increases with increasing frequency) and it operates in the “idle” mode. In this case, the valve 6 is closed, and the valve 8 is open. In the downhole water pre-discharge unit 1, the incoming oil-gas mixture is divided into partially dehydrated oil, gas and water. Partially dehydrated oil and gas are discharged through the drain pipe 3. The discharged water through the drain pipe 4 enters through the bypass line 4 into the drain pipe for the partially dehydrated oil and gas 3. The quality of the discharge water is determined by a device for determining the quality of water 5. If the quality of the discharge water satisfies the geological conditions of the reservoir into which the injection is carried out, the valve 6 opens and the valve 8 closes. Water enters the pump-changer 11 in the injection well 9. The pump-pervert 11 creates sufficient water pressure for injection into the formation, and then it enters the well zone below the packer 12 through the tubing string 10 the operation of the device for implementing the inventive method of cluster discharge and utilization of produced water during a certain period of time, for example a week, the supply of the pump-changer 11 is increased (for example, up to 40 Hz with a frequency range of 35-60 Hz) and the operations are repeated.

Thus, the claimed method of cluster discharge and disposal of produced water is more efficient than the prototype due to the quality control of the water supplied to the injection well and the possibility of regulating its supply. The inventive method of cluster discharge and disposal of produced water eliminates the injection of incompatible water into the formation. The inventive method of cluster discharge and disposal of produced water eliminates the injection into the reservoir of low-quality water.

Claims (3)

1. The method of cluster discharge and utilization of produced water, including measuring the injectivity of the injection well, supplying the products of one or more producing wells to the well for preliminary water discharge, measuring the amount of crude oil and gas, as well as the water cut of crude oil, oil and water densities entering into the well for preliminary water discharge, dividing the products into partially dehydrated oil, gas and water, sending partially dehydrated oil and gas to the collection manifold, discharged water to the supercharger well, characterized in that the compatibility of the discharged water with the water of the formation into which it is injected from the injection well is determined, with the compatibility of the water, the injection well is equipped with a device to create sufficient water pressure to pump water into the formation, configured to change the flow and installed on minimum supply, determine the conformity of the quality of the discharged water to the geological conditions of the reservoir, if the quality of the discharged water is unsatisfactory, it is sent to the collection header , with satisfactory quality of the discharged water, it is sent to the injection well, the amount of discharged water entering the injection well is measured, then, with a selected constant or variable step, the supply of the device for creating water pressure is increased, and this increase is made until the quality of the discharged water satisfies geological conditions of the reservoir. 2. The method according to claim 1, characterized in that the pressure of the discharged water at the outlet of the well is created for preliminary discharge of water higher than in the collection header. 3. The method according to claim 1, characterized in that the degassing of the discharged water is carried out, for example, by oscillation.