RU2343953C1 - Facility for preliminary discharge of water from oil well production - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: facility consists of pipelines of oil well production supply to distributing unit connected by means of steadying collector with preliminary separation unit, which by means of output sleeves of preliminary separated gas, oil and water is connected with oil-gas separator, equipped with pipelines of gas, oil and water output. The device for withdrawing and supply of part of dry oil is furnished with an itinerary oil heater and with a dozing and supplying block of chemical reagent.

EFFECT: upgraded efficiency of facility, increased quality of water purification, reduced consumption of demulsifier and increased oil gas utilisation.

5 cl, 1 dwg

Description

The invention relates to the field of equipment for the preparation of produced products and can be used in pressurized collection systems for preliminary discharge of water from oil well products.

A known installation for preliminary discharge of water from oil well products, involving the collection of well products at a distribution unit, the separation of the oil-gas mixture into oil gas, oil and water in an oil field separator and the subsequent removal of oil gas, oil and water / Development and operation of oil and gas fields. Muravyov I.M. and others. 3rd edition, revised and supplemented. - M .: Nedra, 1970. - P.345 /.

The disadvantages of the known installation are:

- insufficient oil dehydration, as the oil field water separator does not allow sufficient oil dehydration;

- insufficient quality of water treatment, since the oil field water separator is not intended for high-quality water treatment;

- increased consumption of the demulsifier, as it is introduced on the distribution node and therefore there is a loss of demulsifier (together with oil gas and water);

- the need to utilize oil gas, which can either be flared (which entails environmental penalties), or built a gas pipeline (which is expensive and not always economically feasible), or pumped out with oil through multiphase pumps (which cannot be done at medium and high gas factor);

- the impossibility of simultaneous destruction of direct, reverse and multiple emulsions, since this requires the sequential introduction of oil and water soluble demulsifiers;

- insufficient performance.

The technical solution closest in technical essence and the achieved result is the installation of a preliminary discharge of water from oil well products, involving the collection of well products at the distribution unit, the separation of the oil and gas mixture into oil gas, oil and water in a still reservoir, preliminary separation into oil gas, oil and water in the preliminary phase separation unit, separate input of pre-separated oil gas, oil and water into the oil and gas separator and removal of oil gas, oil and water from the oil and gas separator, while the demulsifier is introduced at the distribution unit / RD 39-004-90. Guidelines for the design and operation of separation units of oil fields, the selection and layout of separation equipment, - Ufa, VNIISPTneft, 1990. - P.31-44 /.

The disadvantages of the known installation are:

- insufficient dehydration of oil, since the oil and gas separator usually does not allow sufficient dehydration of oil;

- insufficient quality of water treatment, since the oil and gas separator is not intended for high-quality water treatment;

- increased consumption of the demulsifier, as it is introduced on the distribution node and therefore there is a loss of demulsifier (together with oil gas and water);

- the need to utilize oil gas, which can either be flared (which entails environmental penalties), or built a gas pipeline (which is expensive and not always economically feasible), or pumped out with oil through multiphase pumps (which cannot be done at medium and high gas factor);

- the impossibility of simultaneous destruction of direct, reverse and multiple emulsions, since this requires the sequential introduction of oil and water soluble demulsifiers.

The problem to be solved and the expected technical result are to increase the efficiency of the installation by ensuring sufficient oil dehydration, improving the quality of water treatment, reducing the consumption of demulsifier and utilization of oil gas.

The problem is solved in that the installation of a preliminary discharge of water from oil well products, including pipelines for supplying oil well products to a distribution unit, connected by a soothing collector to a preliminary separation unit, which is connected by pipes to exhaust pre-separated gas, oil and water with an oil and gas separator having pipelines drainage of gas, oil and water, characterized in that the pipeline for drainage of oil is connected to the apparatus for dehydration of oil; moreover, the oil dehydration apparatus is equipped with a device for taking part of the dehydrated oil and supplying it to the outlet pipe for pre-separated oil or to the pipe outlet for pre-divided oil and to the oil pipe.

The device for selecting a portion of dehydrated oil and supplying it is equipped with a track oil heater.

A device for the selection of a portion of dehydrated oil and its supply is equipped with a dosing and supply unit of a chemical reagent, for example a demulsifier.

The unit for dosing and supplying a chemical reagent is arranged to periodically change the supplied chemical reagents, for example, oil and water soluble demulsifiers.

The pipeline for draining water from the oil and gas separator is connected to a device for the purification of water.

The receipt and subsequent dehydration of oil in the dehydration apparatus allows to provide the required oil dehydration.

The removal of water from the oil and gas separator for aftertreatment in the installation for aftertreatment of water, from where it is pumped, for example, to the reservoir pressure maintenance system, ensures the required quality of water treatment.

The selection of a part of the oil drained from the dehydration apparatus and the subsequent introduction together with the pre-separated oil into the oil and gas separator and / or with the oil into the dehydration apparatus can improve the quality of the separation of the oil-water emulsion and the oil dehydration.

The addition of a demulsifier to the drained oil allows to reduce the consumption of the demulsifier, since its losses are excluded along with oil gas and water.

The alternation of oil- and water-soluble demulsifiers added to the withdrawn oil, for example, once every 12 hours or a day allows the destruction of direct, inverse and mixed emulsions.

Heated selected oil, for example, in a track oil heater with oil gas, can increase oil dehydration, reduce the consumption of demulsifier and utilize oil gas.

With a high content of oil gas in the production of oil wells, it is possible to divert part of the oil gas after the distribution unit, for example, from a separator installed after the distribution unit.

A variant of the installation of the preliminary discharge of water from oil production is shown in the drawing. Here:

1 - pipelines for the supply of oil wells

2 - distribution node

3 - soothing collector

4 - preliminary separation unit

5, 6, 7, - branch pipes for the removal of previously separated gas, oil and water

8 - oil and gas separator

9 - pipeline for the removal of oil from the oil and gas separator

10 - oil dehydration apparatus

11 - pipeline for the removal of gas from the oil and gas separator

12 - pipeline drainage of oil and gas separator

13 - device for water purification

14 - water drainage line

15 - a device for the selection of part of the dehydrated oil and its supply

16 - dehydrated oil supply line

17 - track oil heater

18 - heated oil supply line

19 - unit for dispensing and supplying a chemical reagent

20 - line input chemical reagent.

Installation works as follows.

Pipelines for supplying oil wells 1, leading from oil wells or oil well clusters, ensure the flow of oil wells to distribution unit 2. Then, the oil and gas mixture moves through the stilling reservoir 3 at a speed of not more than 1 m / s for 2-3 minutes. In the stilling reservoir 3, the oil-gas mixture is stratified into oil gas, oil and water. Next, the stratified water-oil and gas mixture enters the preliminary phase separation unit 4, where the separation of the stratified oil-gas mixture into pre-separated oil gas, oil and water, which through the corresponding nozzles 5, 6 and 7 enter the oil and gas separator 8, where the separation into oil gas occurs, oil and water.

Through the pipeline for oil drainage 9 from the oil and gas separator 8, oil enters the oil dehydration apparatus 10, where oil is dehydrated to the required parameters (for example, Rosneft requires oil dehydration up to 1%).

From the upper part of the oil and gas separator 8, petroleum gas is discharged through a gas exhaust pipe 11.

From the lower part of the oil and gas separator 8, through the water drainage pipe 12, water enters the device for the post-treatment of water 13, from where the purified water flows through the water drainage line 14 to the reservoir pressure maintenance system of the field.

From the oil dehydration apparatus 10, dehydrated oil is supplied to the oil preparation unit.

Part of the dehydrated oil from the oil dehydration apparatus 10 enters the device 15 for taking part of the dehydrated oil and supplying it through the dehydrated oil supply line 16 to the oil track heater 17, where it is heated with oil gas (for example, for Volga oils 70 ... 75 ° C) .

A demulsifier is introduced into the heated dehydrated oil moving along the heated oil supply line 18 using the dosing and supply unit of the chemical reagent 19. Since the direct and mixed or inverse and mixed emulsions can exist simultaneously, oil and water-soluble emulsions, for example, after 12 hours or a day.

Heated oil with a demulsifier through the input line of the chemical reagent 20 is fed to the input of the oil dehydration apparatus 10. Since the demulsifier is supplied directly to the heated oil and then to the oil-water emulsion, this reduces the consumption of the demulsifier (there is no loss of the demulsifier with water and oil gas); demulsification efficiency is also enhanced by heating the emulsion with oil.

Thus, the claimed invention allows for sufficient dehydration of oil, to improve the quality of water purification, to reduce the consumption of demulsifier and to utilize oil gas.

Claims (5)

1. Installation of a preliminary discharge of water from oil well products, including pipelines for supplying oil well products to a distribution unit connected by a soothing collector to a preliminary separation unit, which is connected by pipes of the previously separated gas, oil and water to an oil and gas separator having gas, oil and gas pipelines and water, characterized in that the oil drainage pipe is connected to the oil dehydration apparatus; moreover, the oil dehydration apparatus is equipped with a device for taking part of the dehydrated oil and supplying it to the outlet pipe for pre-separated oil or to the pipe outlet for pre-divided oil and to the oil pipe. 2. Installation according to claim 1, characterized in that the device for selecting part of the dehydrated oil and supplying it is equipped with a track oil heater. 3. Installation according to claim 1 or 2, characterized in that the device for selecting a portion of the dehydrated oil and supplying it is equipped with a dosing and supply unit of a chemical reagent, for example a demulsifier. 4. The installation according to claim 3, characterized in that the unit for dispensing and supplying a chemical reagent is configured to periodically change the supplied chemical reagents, for example, oil and water soluble demulsifiers. 5. Installation according to claim 1, characterized in that the pipeline for draining water from the oil and gas separator is connected to a device for the purification of water.