RU2721518C1 - Mobile unit for processing emulsion intermediate layers of well products - Google Patents

Abstract

FIELD: oil, gas and coke-chemical industries.

SUBSTANCE: invention relates to oil industry and can be used in crude oil treating plants (COTP) during processing of stable emulsion intermediate layer for preparation of commercial oil and formation water to the required quality group. Mobile plant is made in the form of separate blocks-containers with possibility of their movement. Plant comprises coarse filter installed in one container unit, homogenisation tank, pump equipment, a chemical reagent feed system, a heat supply system comprising a heat carrier container, a pump, a heat exchange device, a dehydration device with inspection windows installed in the second container unit and a desalination device, and a fresh water supply system. Supply system includes a reservoir for fresh water, a pump and dispersants. Plant includes control and measuring equipment, pipelines system interconnecting the equipment of container blocks with each other. Device comprises auger horizontal precipitation centrifuge placed in separate container unit. Centrifuge separates water-oil emulsion into oil, water and solid phases. Centrifugal plate-type separator for water treatment is also arranged in separate container unit. Separator is connected to stationary water tank by pipeline of finished water discharge, with drainage tank - pipeline of residual oil removal, with dehydration and desalting tanks - with bottom water pipelines, with fresh water capacity - with fresh water pipeline. Output of heat exchange device is connected to input of screw horizontal centrifuge by pipeline of heated water-oil emulsion supply. Screw horizontal centrifuge is connected with dehydration tank by oil phase pipeline, and with centrifugal plate-type separator - pipeline of separated water phase. Drainage tank is connected to homogenisation tank by recycling pipeline for oil return not meeting commercial oil quality requirements.

EFFECT: technical result is wider range of use of mobile installation, high quality of processing intermediate emulsion layers and commercial water.

1 cl, 4 tbl, 1 dwg

Description

FIELD OF THE INVENTION

The invention relates to the oil industry and can be used in oil field treatment plants (UPPN) in the processing of a stable emulsion intermediate layer for the preparation of marketable oil and produced water to the required quality group.

State of the art

A known method of processing oil-containing sludge (RF patent 2217476, publication date 27.11.2003, class IPC C10G 31/10), including dilution of oil sludge with oil, heating and separation in a three-phase decanter centrifuge for oil, water and concentrate of solids. The disadvantage of this method is the inability to obtain a final product that meets the requirements of GOST R 51858-2002 in the oil phase and OST 39-225-99 in the aqueous phase, after processing oily sludge.

A known method of processing the emulsion of the oil-water intermediate layer (RF Patent 2177025, publication date 20.12.2001, class IPC C10G 31/10, C10G 33/04), including heating the emulsion of the oil-water intermediate layer, processing it with a demulsifier, acoustic coalescence in ultrasound field, two-stage centrifugation and separation into solid and liquid phases. The disadvantage of this method is the lack of mobility of the technological complex of equipment, as well as the impossibility of its rearrangement for the preparation of intermediate layers of variable composition in case of mobilization at another object of preparation or collection of the initial product from another technological device.

Known mobile installation for cleaning tanks from oil sludge and asphalt tar and resin deposits (RF patent No. 71911, class IPC B08B 3/08, publication date. 03/27/2008), including a tank for working fluid, engine room, hydraulic system, including stop valves and pump unit , the capacity of petroleum products placed on one vehicle. In addition, the installation is equipped with a coalescence-flotation separator, in which the phase separation of the emulsion into oil product, working fluid and mechanical particles, as well as cleaning of the working fluid and oil product vapors pumped from the cleaned reservoir, takes place. The installation includes a system of gas-air heating of the working fluid, which is used as water, liquid hydrocarbons or aqueous solutions of detergents. The pump unit includes an emulsion transfer pump and an oil product transfer pump, a high-pressure pump for supplying a working fluid, a solution transfer pump, a submersible screw pump for lifting high-viscosity oil products and an ejector pump. The disadvantage of this installation is the inability to complete the preparation of the intermediate layer to salable oil according to GOST R 51858-2002 to bring the quality of produced water to OST and the lack of equipment designed for the process of oil desalination.

A well-known mobile installation of a three-stage separation of oil sludge (http://otrabotka.com), manufactured by Huning Umwelttechnik (Germany), mounted on a metal frame, the length of the container is about 12 meters. The equipment, located in one tier, includes a pump that pumps raw material into a vibratory separator, before feeding into which the raw material is heated to 50 ° C by pre-mixing with already separated and heated oil sludge. In a vibratory separator, solids of more than 1 mm in size are screened out in a screw conveyor for directing to the MSW tank. The liquid phase of the oil emulsion is collected in an intermediate tank with a stirrer to homogenize the liquid and prevent precipitation of the remaining solid phase. Part of the liquid from the same tank is pumped out for use in the heating cycle of the feedstock, the rest is sent to the decanter, after heating the mixture in a heat exchanger. The solid phase (mechanical impurities) is sent from the decanter to the sludge collection tank. The raw material heated in the intermediate heat exchanger is sent to the inlet of the three-phase centrifuge, after which the solid precipitate from the centrifuge is sent to the MSW container. The unit is equipped with two 250-liter tanks with demulsifiers with metering pumps. Pure oil is accumulated in a separate tank. Water recovered from oil sludge is additionally filtered and accumulated in the tank. Coarsely refined petroleum products are returned back to the inlet of the decanter. The disadvantage of this installation is the lack of equipment designed for the process of oil desalination in order to bring the quality of oil to the product group according to GOST 51858-2002 on the content of chloride salts.

The closest analogue (prototype) in terms of functionality and design to the proposed device is the installation for the preparation of well products (RF patent No. 2616466, IPC B01D 17/02, B01D 36/00, B01D 19/00, date of publication April 17, 2017), including a collection and degassing tank for downhole products, a dewatering device, pumps, a heat exchange device, measuring instruments, piping, shut-off and control equipment, while the installation is placed in a box-type prefabricated case, equipped with a device for oil desalination associated with a fresh water supply system. The body of the device for oil dehydration contains viewing windows and partitions mounted inside the housing on rails with the possibility of moving partitions along them. A fine filter with the ability to change filter media and filter screens is installed on the formation water discharge pipeline. A section of the pipeline connecting the coarse filter with the heat exchanger is branched into two lines, one of which passes through the collection and degassing tank of well products.

The disadvantage of this design is the limited range of use of this installation, associated with the lack of equipment designed for the processing of persistent oil-water emulsions with a high content of solids.

Disclosure of the invention

The objective of the present invention is to develop a mobile installation for processing intermediate emulsion layers to bring oil and produced water to the desired quality group.

The technical result achieved by using the proposed design of the installation is to expand the range of use of equipment of the mobile installation, as well as to improve the quality of processing industrial layers and produced water.

The technical result, which consists in expanding the range of use of the mobile unit, is achieved due to the fact that the mobile unit for processing intermediate layers of well products is made in the form of separate container blocks with the possibility of their movement, contains a coarse filter, homogenization tank, pumping unit installed in one container block equipment, a chemical reagent supply system, a heat supply system containing a container for a coolant, a pump, a heat exchanger, and also a dehydration device with inspection windows and a desalination device installed in a second container block, a fresh water supply system including a fresh water tank, a pump, dispersants, as well as control and measuring equipment, a piping system connecting the equipment of the container blocks to each other, while the installation contains a horizontal screw sedimentation centrifuge located in a separate block container, carrying out the separation of the oil-water emulsion into oil, water and solid phases, and a centrifugal disk separator for water treatment, also located in a separate container block, connected to a stationary water tank by a pipeline for the removal of produced formation water, with a drainage tank - a pipeline for the removal of residual oil, with tanks dehydration and desalination - with pipelines of produced water, with a capacity of fresh water - piping of fresh water, while the output of the heat exchanger is connected to the inlet of a horizontal screw centrifuge by a pipe for supplying a heated oil-water emulsion, a horizontal screw centrifuge is connected to a tank of dewatering by a pipeline of an oil phase, and with a centrifugal plate - a pipeline of the separated aqueous phase, while the dewatering tank is connected to the homogenization tank by a recycling pipeline to return oil that does not meet the quality requirements of the commercial oil.

Brief Description of the Drawings

In FIG. 1 shows the general layout of equipment in containers.

The implementation of the invention

A mobile installation for processing stable emulsion intermediate layers and preparing produced water consists of 4 technological block containers 1, 2, 3, 4. A coarse filter 5, a container 6 for homogenizing the intermediate layer of the oil-water emulsion, pump 7, are installed in the block container 1 a chemical reagent supply system, including a reagent tank 8 and a metering pump 9, a heat supply system, including a heat carrier tank 10 with electric heaters, a pump 11, a heat exchange device 12.

In the container block 2, there is a horizontal screw precipitation centrifuge of continuous operation 13, the main node of which is a rotor of a cylindrical shape located horizontally. Inside the rotor, a screw is located coaxially with it, intended for transportation of the precipitated precipitate of a solid phase (cake). In the second container there is also an intermediate tank for collecting oil 14, a pump 15, a cylinder of nitrogen 16.

In the container block 3, a fresh water supply system is installed, including a fresh water tank 17, a pump 18, two continuous oil desalination devices (dispersants) 19, a dehydration device 20 made in the form of a tank with viewing windows, and a desalination device 21 made in form of capacity.

In the block container 4, a formation water treatment system is installed, including a piping system and a centrifugal disk separator 22, the drain of which is hydraulically connected to the drainage tank 23.

Each of the container blocks is placed on one or more vehicles, providing the possibility of their movement by any type of transport.

The piping system of the mobile unit includes

- pipeline 24 for supplying oil-water emulsion to the tank 6 of the container block 1

- pipeline 25 for the supply of water-oil emulsion from the tank 6 through the pump 7 to the input of the heat exchanger 12 of the container block 1

- pipe 26 for supplying the reagent-demulsifier, connecting the output of the tank 8 with the pipe 25 before the input of the oil-water emulsion into the heat exchanger 12 of the container block 1

- a pipeline 27 for supplying a heat carrier (ethylene glycol) from a tank 10 to a heat exchanger 12 of a container block 1

- a pipeline 28 for supplying a heated oil-water emulsion from the heat exchanger 12 of the container block 1 to the inlet of the centrifuge 13 of the container block 2

- pipeline 29 of the removal of the oil phase, connecting one of the outputs of the centrifuge 13 with the input of the dehydration tank 20

- pipeline 30 for supplying the reagent-demulsifier from the tank 8 to the pipeline 29 for supplying the oil phase before entering the dewatering tank 20

- a pipe 31 for supplying heated fresh water, through one of the dispersants 19, from the tank 17 to the pipeline 29 for supplying the oil phase before entering the dewatering tank 20

- a pipeline 32 of dehydrated oil connecting the outlet of the dehydration tank 20 to the inlet of the desalination tank 21

- a pipe 33 for supplying heated fresh water, through one of the dispersants 19, from the tank 17 to the pipeline for supplying dehydrated oil 32 before entering the desalination tank 21

- pipeline 34 for the removal of finished oil from the desalination tank 21 to a stationary storage tank (not shown in the figure)

- a pipeline 35 for separating the separated aqueous phase from the centrifuge 13 to the inlet of the separator 22 located in the container block 4

- pipeline 36 for separating separated commercial water from the dewatering tank 20 to the input of the separator 22

- pipeline 37 for removal of produced water from the desalination tank 21 to the input of the separator 22

- pipeline 38 for supplying fresh industrial water from the tank 17 to the separator 22

- pipeline 39 of the removal of the cooled coolant from the heat exchanger 12 into the tank 10

- pipeline 40 of oil recycle from dehydration tank 20 to tank 6

- pipeline 41 of oil recycle from the desalination tank 21 to the dewatering tank 20 (Fig. 3)

- pipe 42 drain from the separator 22 of the finished produced water

- pipeline 43 for removal of residual oil from the separator 22 to the drainage tank 23

- pipeline 44 of the outlet of heated produced water from the heat exchanger 12 to the inlet of the dewatering tank 20 (Fig. 2)

- pipe 45 recycle water in the capacity of desalination 21 (Fig. 2).

The versatility of the mobile unit is that at the UPPN it can be used either for the preparation of marketable oil and produced water at the same time, or for the preparation of only marketable oil, or only for the preparation of produced water.

The layout options for container blocks depending on the properties and composition of the initial product for the preparation of the oil phase to the product quality group according to GOST R 51858-2002 are presented in Table 1.

The properties of the starting product are presented in Table 2.

The main parameters of the operating mode of the mobile installation for processing stable emulsion intermediate layers are given in Table. 3.

The layout options for container blocks, depending on the task at hand, are presented in Table 4.

The following describes the operation of a mobile installation for processing intermediate layers of well products to produce salable oil and produced water.

A mobile unit for processing intermediate layers of well products to produce marketable oil that meets the requirements of GOST R 51858-2002 and produced water for injection into a formation that meets the requirements of OST 39-225-99 (Table 4, task No. 3) works as follows: - mobile the installation is connected to the piping of the existing facility. The oil-water emulsion from the technological apparatus of the oil preparation facility is sent through pipeline 24 through a valve to a coarse filter 5 and then through a valve to a container 6 for homogenizing the products of block container 1. The pressure and temperature of the incoming oil emulsion are monitored by pressure and temperature sensors. In the tank 6 produce the accumulation and homogenization of the oil-water emulsion. The measurement of the main parameters of the oil-water emulsion located in the tank 6 is carried out using a pressure sensor and a level gauge. Next, the homogenized oil-water emulsion using the pump 7 through the pipe 25, is sent to a heat exchanger 12 located in the same block container 1, where it is heated to a temperature of at least 70 ° C. In the pipeline section 25, before entering the heat exchange device 12, the flow of oil-water emulsion is under pressure of 0.015-1 MPa, at a temperature of + 5 ° C. Before entering the heat exchange device 12, into the flow of the processed oil-water emulsion, from the tank 8 through a pipe 26, a demulsifier is supplied through a metering pump 9, and the pressure of the processed oil-water emulsion is measured using a pressure gauge. The reagent-demulsifier is fed into the pipeline 25 under a pressure of 0.015-1 MPa at a temperature in the range from 5 ° C to 40 ° C. To heat the treated oil-water emulsion and produced water in the block container 1 of the universal mobile unit, a heat supply system is provided, including a tank 10 for a heat carrier with electric heaters, a pump 11 for circulating a heat carrier, a heat exchange device 12, piping. Ethylene glycol is used as a heat carrier for heating the treated oil-water emulsion. From the tank 10, the coolant, heated to 70-95 ° C, enters the pump 11, which through cranes feeds it through a pipe 27 to the inlet pipe of the heat exchanger 12. Passing through the heat exchanger 12, the coolant, cooling the treated oil-water emulsion, cools, and then , through the return pipe 39 it is sent back to the tank tank 10 for re-heating. The pressure and temperature of the coolant on the forward and reverse lines are measured using pressure and temperature sensors. At the outlet of the tank 10, the coolant flow is under a pressure of 0.015-1 MPa, at a temperature of + 70 ° C. The temperature control of the processed oil-water emulsion after the heat exchange device 12 in the pipe 28 is carried out by changing the flow rate of the coolant and the number of included heaters of the tank 10.

Next, the flow of the processed oil-water emulsion through the pipeline 28 is directed to the inlet of a horizontal three-phase centrifuge 13 located in the container block 2, in which, under the action of centrifugal forces, the stable oil-water emulsion of the treated industrial layer is divided into three phases: oil, water and solid. The oil phase through the pipeline 29 is directed to the inlet of the dehydration tank 20, located in the container block 3, for its deep dehydration. Before the oil phase is supplied to the dehydration tank 20 through the pipe 29, from the tank 8 through the pipe 30, a demulsifying agent is introduced into it, and fresh water heated to 70 ° C is introduced through the pipe 31 from the tank 17. In the dehydration tank 20, the thermochemical process of preparing the oil phase is carried out, which consists in the separation of the oil-water emulsion into oil and water, while reducing the content of chloride salts in the produced oil, as well as reducing the content of oil products and solid suspended particles in the produced produced water. When the dehydrated oil leaves the dehydration tank 20, the content of water in it is controlled by a hydrometer through the upper pipe. In the case of a water content of more than stipulated by the standard (up to 1%), the oily liquid through the pipeline 40 (Fig. 3) in recycling mode is sent back to the tank 6 of the container block 1.

Further, through the pipeline 32, the dehydrated oil is supplied to the desalination device 21 located in the container block 3. In the pipeline 32, before the oily liquid enters the desalination tank 21, the heated fresh water from the tank is supplied through the pipeline 33 through one of the dispersants 19 17 fresh water supply systems to reduce the salt content in the finished product.

The fresh water supply system, also located in the container block 3, includes a tank-tank 17 with electric heaters, a pump 18, dispersants 19. For the accumulation and further supply of fresh water to the pipeline system of a universal mobile device, the tank-tank 17 is connected to the existing supply system fresh water at the oil field. From the tank 17, fresh water is sent to the inlet of the pump 18, and then, through dispersants 19, designed for intensive mixing of various liquids and provided for supplying fresh water heated to 70 ° C. The control parameters of the cleaned oil-water emulsion is carried out using temperature, pressure and flow sensors.

In the demineralization tank 21, the final process of separating the oil-water emulsion into dehydrated, desalted oil and water is carried out, the salt content in the finished product is reduced by removing desalinated formation water from the oil due to the thermochemical process of desalination. The parameters of the cleaned oil-water emulsion are measured using a pressure sensor and a level gauge. At the outlet of the desalination tank 21 into the pipeline 34, the oil flow has the following parameters: pressure of 0.015-1 MPa at a temperature of from 5 ° C to 70 ° C. In the process of desalination, they achieve compliance with the quality of marketable oil of the 1st group according to GOST 51858-2002.

The aqueous phase, after exiting the horizontal three-phase centrifuge 13, through the pipeline 35, and separated commercial water from the tanks 20 and 21, through the pipelines 36 and 37, is directed to the reception of a centrifugal disk separator 22, placed separately in the container block 4, where they are brought water quality to the requirements of OST 39-225-99 for the preparation of water for injection into the reservoir. The water, ready for injection into the reservoir, is diverted via pipeline 42 into a stationary tank. Pure water is supplied to the separator 22 for preparing produced water through a pipe 38 from a tank 17 of the fresh water supply system of the container block 3. Residual oil is removed from the separator 22 to a drain tank 23 through a pipe 43. Thus, for the preparation of marketable water and reservoir oil of the required quality, equipment located in 1, 2, 3 and 4 container blocks is used.

Claims (1)

A mobile unit for processing intermediate layers of well products made in the form of separate blocks-containers with the possibility of their movement, containing a coarse filter, homogenization tank, pumping equipment, a chemical reagent supply system, a heat supply system containing a coolant container installed in one block container a pump, a heat exchanger installed in the second container block, a dehydration device with inspection windows and a desalination device, a fresh water supply system including a fresh water tank, a pump, dispersants, as well as control and measuring equipment, a piping system, connecting equipment of blocks -containers between themselves, characterized in that it contains a horizontal horizontal sedimentation centrifuge located in a separate block container, which separates the oil-water emulsion into oil, water and solid phases, and a centrifugal disk separator for water treatment, also placed in a separate container block, connected to the stationary water tank by the finished water drainage pipe, with a drainage tank - residual oil drainage pipe, with dewatering and desalination tanks - produced water pipelines, with fresh water tank - fresh water pipeline, while the heat exchange device is connected to the inlet of the horizontal screw centrifuge by the heated water-oil emulsion supply pipeline, the horizontal screw centrifuge is connected to the dewatering tank by the oil phase pipeline, and the centrifugal plate separator is connected to the separated aqueous phase pipe, while the dewatering tank is connected to the homogenization tank for oil return by the recycling pipeline not complying with the quality requirements of commercial oil.

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