RU2314140C2 - Installation of discharge of the associated water - Google Patents

Abstract

FIELD: oil-producing industry; other industries; installations of discharge of the associated water at the oil fields.

SUBSTANCE: the invention is pertaining to the installation of discharge of the associated water, which represents the slant big-diameter pipeline with the considerable length and used for separation of the water from the oil and gas directly in the area of extraction of the multiphase products. The liquid-gas flow in the installation is divided into the water and oil parts and gas parts due to the action of the gravitational force and the installation design. To exclude the petroleum getting in the water discharge fitting pipe at the installation mode change the installation has in its lower part the water-collecting fitting pipe with the ball and the annular saddle-type seat. The ball has the intermediate firmness between the associated water and the oil-water suspension. At approaching of the oil-water partition (OWP) to the fitting pipe of the water discharge the ball under action of the formed pressure fall with advance of the OWP closes the hole in the annular saddle-type seat going to the fitting pipe of the water discharge. To start-up the installation mode operation the water discharge fitting pipe is supplied with the slide shutter and the line with the valve of pressure equalization above and below the ball at its presence on the annular saddle-type seat. The technical result of the invention consists in the absence of the expenditures on cleaning of the separated associated water from petroleum of the water ducts, pumps and other users equipment.

EFFECT: the invention ensures the absence of the expenditures on cleaning of the separated associated water from petroleum in the water ducts, pumps and other users equipment.

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Description

The present invention relates to the refining industry and can be used in oil, gas and water collection systems for preliminary separation of associated produced water.

A known installation of water discharge (RF patent No. 2098166, class B01D 19/00, publ. 10.12.97, bull. No. 34), containing two inclined separation pipes connected by jumpers, a damper for entering the gas-liquid mixture and nozzles for the removal of oil and gas and water. The gas-liquid mixture (GHS) in the installation is divided into water and oil and gas parts due to the force of gravity and the design of the separation pipes - their considerable length and a certain angle of inclination of these pipes to the horizon. The oil-water section (VNR) in the installation is supported in the upper part of the separation pipes by adjusting the flow rates of liquids using valves at the inlet and outlet of the installation. The disadvantage is that with an increase in the proportion of oil in the incoming GHS, the VNR decreases and penetrates the pipe for water drainage. This leads to oil clogging of pipelines, pumps and consumer tanks - cluster pumping stations.

Known installation for water discharge in the form of a pipe water separator (TVO), equipped with an oil-water level regulator (article "Improving the preliminary water discharge at the fields of OAO" Yuganskneftegaz "in the journal" Oil Industry ", 2003, No. 4, p.114- 116, fig. 2).

The level regulator is installed on the line (branch pipe) of the water drain, it is an electric valve, the flow rate of which is regulated by the interface sensor located in the upper part of the TVO. Such high-tech equipment requires electrical energy and significant financial costs for the purchase, installation and operation of the device. When electric power is turned off, a level sensor or an electric valve breaks down, it is possible that oil will enter the water discharge pipe when the unit exits normal operation.

The aim of the invention is to prevent the ingress of oil into the pipe drainage when approaching the oil-water section to the bottom of the installation. This goal is achieved in that a water discharge installation comprising nozzles for supplying a gas-oil mixture, gas, oil and water drainage, an inclined pipe with a flow damper for introducing a gas-oil mixture, a smaller diameter gas exhaust pipe is configured so that the water discharge pipe is supplemented with a valve and connected with an inclined pipeline in its lower part and has its continuation inside an inclined pipeline in the form of a uniformly perforated drainage pipe with a covered top and a ball inside with a pl A ratio less than the density of the discharged water, but greater than the density of the water-oil emulsion entering the installation, the transition of the drainage pipe into the pipe for water drainage is equipped with a saddle in the form of a ring with a passage diameter smaller than the diameter of the ball, and the total area of the openings of the drainage pipe is significantly exceeds the area of the drain hole of the saddle, and part of the pipe for water drainage between the saddle and the valve is connected through the valve to a pipe with an inclined pipe.

The installation diagram of the water discharge is shown in the drawing.

The installation includes an inclined pipe 1, a gas exhaust pipe 2, a flow damper 3, a nozzle 4 for supplying a gas-oil mixture to the damper, a nozzle 6 for draining the separated water, a drainage nozzle 7, a ball 8, a saddle 9, a valve 10, a pipe 11 and a valve 12.

Installation of water discharge works as follows.

The multiphase composition of oil, gas and water enters through the damper 3 into an inclined pipeline 1 and, under the influence of gravity, is divided into water and gas-oil parts. In the operation of the installation, the oil-water section is located in the upper part of pipelines 1 and 2 near the damper 3. In the lower part of pipeline 1 there is discharged water freed from oil, therefore a ball 8 with a lower density floats in such water under the influence of the Archimedes force and is located in the upper part of the catchment nozzle 7. The total area of the holes in the nozzle 7 is much greater than the area of the drain hole of the saddle 9, so the speed of water movement inside the nozzle 7 is equal to the steady speed of water in the inclined pipe wire 1. This situation changes in the absence of sludge from the multiphase mixture entering the unit. The oil-water section will decrease and will reach ball 8 through the openings of nozzle 7. In such a mixture, the ball will sink due to its greater density and will remain in the BHP zone of the downward flow all the time. When VNR moves down, the number of holes of the pipe 7 under the ball 8 will decrease and there will come a time when the area of the holes of the drainage pipe 7 will be comparable and even less than the area of the drain hole of the saddle 9. Then the speed of water movement under the ball 8 will exceed the speed of the oil-water section in pipeline 1. Based on the laws of hydraulics (Bernoulli equation), the pressure under ball 8 will become lower than above it. Since the annular gap between the ball and the pipe 7 has a small area, the ball 8, under the influence of the pressure drop formed, will be attracted to the saddle 9 earlier than the BHP will drop to the saddle. Thus, the goal will be achieved - water and oil will not get into the pipe for water drainage.

After the ball 8 is planted on the saddle 9, the water discharge installation will temporarily cease to fulfill its purpose. With the advent of the gravitational separation of GHS into the water and oil and gas parts, the VNR will rise up and reach its optimal zone near the damper 3. To start the installation in normal operation, it is necessary to close the valve 10 and open the valve 12. Thanks to the tube 11, the pressure above and below the ball 8 is equalized, after whereupon the ball 8 will float up and take its upper position in the catchment pipe 7. At the end of the installation start-up, the valve 12 closes and the valve 10 opens to discharge the clean water to the consumer.

The proposed improvement of the associated water discharge installation, which consists in regulating the position of the ball with a given density as a shut-off valve, gives the installation a new function - without the participation of personnel and volatile technical devices, the water discharge line is protected from water-oil emulsion. The uniformity of perforation of the catchment pipe and the definition of the gap between the ball and the catchment pipe with a small area determine a new technical effect - the ball drops to the saddle until the BHP approaches the saddle.

The operational efficiency of the proposed installation is the absence of costs for cleaning oil from pipelines, pumps and other equipment of consumers of separated associated water.

Claims (1)

A unit for venting associated water, including nozzles for supplying a gas-oil mixture, gas, oil and water drainage, an inclined pipe parallel to which a gas discharge pipe is located, a flow damper before supplying a gas-oil mixture to an inclined pipe, characterized in that the pipe for water drainage is supplemented with a valve, is connected with an inclined pipeline in its lower part and has its continuation inside an inclined pipeline in the form of a uniformly perforated catchment pipe with a covered top and a ball inside with a density less than the density of the discharged water, but greater than the density of the water-oil emulsion entering the installation, the transition of the drainage pipe into the pipe for water drainage is provided with a saddle in the form of a ring with a passage diameter smaller than the diameter of the ball, the total area of the perforated holes of the drainage pipe significantly exceeds the area of the drain hole of the saddle, and part of the pipe for water drainage between the saddle and the valve is connected through the valve to a pipe with an inclined pipe.