KR20130022193A

KR20130022193A - Water treatment apparatus and method for enhancing oil recovery

Info

Publication number: KR20130022193A
Application number: KR1020110085024A
Authority: KR
Inventors: 정대영; 함영창; 조용성; 김호형
Original assignee: 대우조선해양 주식회사
Priority date: 2011-08-25
Filing date: 2011-08-25
Publication date: 2013-03-06

Abstract

PURPOSE: A water treatment device capable of enhancing oil collecting and a method are provided to prevent system impact with respect to enhancing a device of oil collecting using an ultraviolet ray exposing method and to reduce maintenance costs of the enhancing device of oil collecting by collecting waste heat. CONSTITUTION: A water treatment device capable of enhancing oil collecting comprises a chamber(300), a ultraviolet ray exposing device(400), and a waste heat collecting device(500). The chamber receives water which is injected in an oil well from the outside and injects the stored water to the oil well. The ultraviolet ray exposing device irradiates ultraviolet rays in the water which is stored in the chamber and collects the waste heat of the water which is injected in the oil well from the chamber. [Reference numerals] (100) First pump; (150) Filtering device; (200) Second pump; (500) Waste heat collecting device; (AA) Seawater; (BB) Demands; (CC) Oil well

Description

Water treatment apparatus and method for enhancing oil recovery

The present invention relates to an apparatus and a method for promoting recovery of crude oil stored in an oil well, and more particularly, to an apparatus and a method for treating waste water and treating water injected into an oil well for improving crude oil recovery.

In order to produce crude oil (petroleum), it is necessary to go through the process of drilling exploration and drilling.

First, in order to produce crude oil (oil), after exploration of the surface or the seabed, the location, size and nature of the nonexistence are estimated based on the exploration results, and based on this, the existence of crude oil (petroleum) is confirmed.

After that, to get additional precise underground information, drilling and exploration work in the basement, which is called drilling exploration.

Drilling work is to drill soil and rock while rotating in the ground using a rotary excavator called a bit.

Rotary drilling can be excavated not only in the vertical direction, but also horizontally or in any direction. It is also possible to dig up to thousands of meters by installing rigs for drilling not only on land but also at sea.

If crude oil (oil) is found during the drilling process, it is transferred to the development and production stage. On the ground, a production unit called a Christmas tree, which extracts crude oil (petroleum) and gas, is installed. On the sea, a platform is installed to produce crude oil.

The offshore platform is installed in various sizes according to the depth of the sea, the size of the oil field, and the distance from the land, and is fixed to the sea floor by using steel and concrete. Holes can be drilled because they use a dynamic positioning system (DPS). The largest platform is a 25-storey building taller than a football field, with more than 500 production engineers.

In the early stages of oil well production, petroleum spews upwards due to the pressure of water under gas or crude oil. This is often called magnetic powder.

Unless the reservoir is very shallow, in general, crude oil (petroleum) flows well in the early stages of production, but if the pressure in the reservoir decreases over time, the production of natural crude oil stops. Most of the crude oil (petroleum) is stored in the reservoir without being produced.

The production of crude oil (petroleum) by natural ejection by pressure in the oil layer is called primary recovery.

Crude oil (petroleum) produced by primary recovery is only 5-15% of reserves. The rest is forcibly recovered by injecting gas into the well or by injecting water, which is called secondary recovery.

After the second recovery, about 70% to 70% of crude oil (oil) remains in the well. Therefore, water vapor, surfactants, hydrocarbon gas, carbon dioxide gas and the like are injected into the oil layer to recover some of them somehow in a state where gas and crude oil (petroleum) are completely mixed, which is called tertiary recovery.

The crude oil coming from the underground is mixed with gas and water, so the gas and water are first separated from the crude oil, and the gas separates the crude oil and water, and removes impurities such as hydrogen sulfide and carbon dioxide. Are temporarily stored in tanks and then transported to destinations by pipelines.

The method for recovering crude oil (petroleum) that is not produced and stored, such as crude oil that requires secondary and tertiary recovery, is called enhanced oil recovery (EOR). Costs are required, resulting in higher production costs of crude oil (oil), and much research is needed to lower the production cost of crude oil (petroleum).

Therefore, the present invention has been invented in view of the above circumstances, and by changing the treatment method for water injected into oil wells for improving crude oil recovery, it is possible to prevent the system impact on the crude oil recovery enhancement device in advance, and to recover waste heat. It is an object of the present invention to provide an apparatus and method for lowering the maintenance cost of a recovery enhancing apparatus.

According to an aspect of the present invention for achieving the above object, in the water treatment apparatus for treating the water to be injected into the oil well in order to improve the recovery of the crude oil stored in the oil well, the water to be injected into the oil well supplied from the outside and stored A chamber 300 for injecting stored water into the well; An ultraviolet irradiation device 400 for irradiating ultraviolet rays to the water stored in the chamber 300; And a waste heat recovery device (500) installed at the rear end of the chamber (300) to recover waste heat of water injected into the well from the chamber (300). to provide.

The waste heat recovery device 500, the heat exchange occurs between the water transfer pipe 250 through which water injected into the oil well from the chamber 300 flows and the low temperature fluid pipe 650 through which the low temperature fluid flows. It is characterized in that to recover the waste heat of the water.

The low temperature fluid is oil or hot water supply water;

It characterized in that it further comprises a; filtration device 150 is installed at the front end of the chamber 300.

It is characterized in that it further comprises; a discharge port 310 is disposed at the lower end of the chamber 300 to discharge the precipitate.

According to another aspect of the present invention, in the water treatment method for treating the water to be injected into the oil well in order to improve the recovery of the crude oil stored in the oil well, water supply step of receiving the water to be injected into the oil well chamber 300 (S10); A water storage step (S20) of storing the water supplied to the chamber 300 for a predetermined time; UV irradiation step (S30) for irradiating the ultraviolet light to the water stored in the chamber 300 by the ultraviolet irradiation device (400); Waste heat recovery step (S40) for recovering the waste heat of the water irradiated with ultraviolet rays; And a water injection step of injecting UV-irradiated water into the oil well (S40).

According to another aspect of the present invention, in the water treatment method for treating the water to be injected into the oil well in order to improve the recovery of crude oil stored in the oil well, the water to be injected into the oil well is irradiated with ultraviolet rays, the water irradiated with ultraviolet light It provides a water treatment method for crude oil recovery, characterized in that for recovering waste heat from the injecting water into the well.

The waste heat is recovered by being delivered to the low temperature oil or low temperature hot water supply water is supplied to the demand destination.

The ultraviolet irradiation is made in the chamber 300 in which water to be supplied to the well can stay for a predetermined time.

According to the present invention, by changing the treatment of water injected into the oil well to improve the oil recovery to the method of irradiating ultraviolet light instead of the method of injecting chemicals to the oil recovery system due to delayed chemical injection to the oil recovery device The system shock that occurs can be prevented in advance.

In addition, the maintenance and repair of the oil recovery apparatus can be performed only by supplying a power supply for the operation of the ultraviolet lamp and replacing the lamp, thereby significantly lowering the maintenance and repair costs of the oil recovery apparatus.

In addition, the removal efficiency of microorganisms can be higher than existing methods using chemicals, and the safety of equipment for improving crude oil recovery is also increased.

In addition, the use of chemicals harmful to the human body increases the safety of the natural environment and the safety of the working environment.

In addition, energy efficiency can be improved by recovering the waste heat of the ultraviolet-treated water.

1 is a view schematically showing a device for improving the existing crude oil recovery.
Figure 2 schematically shows a water treatment apparatus for crude oil recovery in accordance with the present invention.
Figure 3 schematically shows a water treatment method for crude oil recovery in accordance with the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the preferred embodiment of the present invention. In the drawings, like reference numerals refer to like elements throughout. The same reference numerals in the drawings denote like elements throughout the drawings.

Crude oil is installed from various production equipment and pulled from the basement (or seabed) to the ground (or sea). In the early stage of production, it is produced smoothly by natural pressure, but over time, the pressure decreases and the output decreases. The stage of oil extraction from the ground includes primary, secondary and tertiary recovery as described above.

Specifically, in the first recovery step, the reservoir is subjected to pressure by some natural mechanism. Groundwater pushes oil toward the borehole, increasing pressure as the gas above the reservoir and the gas contained in the crude oil expand. Sufficient underground pressure in the reservoir will push oil to the surface and align complex valves on the wellhead to connect to the pipelines for oil storage or disposal. Recovery rates in the first recovery stage are usually around 5-15%.

In the second recovery phase, the oil pressure gradually decreases over a period of time, making it impossible to push the oil to the surface. As described above, when the pressure of the oil reservoir decreases due to magnetic force, the secondary recovery method is performed.

External energy in the form of fluid is injected to artificially raise the pressure in the reservoir to push the oil out. Sometimes an oil pump is used to drain the oil, and another secondary recovery method is water (water) or gas. In addition, air, carbon dioxide, and other gases are injected to clean the wells, increasing oil flow and increasing production. The recovery rate from water injection is usually 30%, depending on the nature of the oil and the characteristics of the reservoir.

In the third stage of recovery, the pressure of the oil bed is not increased, but the viscosity of the crude oil itself is increased to improve the permeability, thereby increasing the yield. Steam is injected into the well, which is the usual method, by turning the gas turbine to generate electricity and injecting the steam generated by the waste heat. This method is mainly used in heavy crude oil production.

This third recovery should only be profitable if it is not feasible with the second recovery method. Therefore, if the oil price is high, the third recovery is performed, but if the oil price is low, it is stopped.

Maximizing recovery in three runs will only take 30-40% of the oil in places.

The manual method of the secondary recovery method is a technique that is generally widely used for recovery recovery. Water is the most preferred recovery promotion method because it has a very good fluidity in the reservoir and is effective for extracting oil, and it can be easily secured and the operation cost is low.

However, the method is simple and inexpensive compared to other crude oil recovery methods, but after a certain time, the oil well is blocked by foreign substances or residues, or underwater microorganisms such as bacteria grow and block the oil well or water supply pipe. There is a need for a water treatment process for treating the chemicals for the water supplied to the filtration device and the oil well, which causes a lot of additional costs, causing a rise in the production cost of crude oil.

In addition, if there is a slight time lag when supplying chemicals and the quality of the water supplied to the well is not met, the water should be discarded, and the water of suitable quality to be supplied to the well again. You have to make it. The system impact on the oil recovery increaser also raises the production cost of crude oil.

In addition, a significant amount of chemicals are used to remove the microorganisms in the water, and the chemicals are very harmful to the body and the environment, and the chemicals leave toxic or residues. In addition, caution should be exercised in the formation of other compounds which may cause secondary contamination.

Ultraviolet light is a light with a wavelength ranging from approximately 0.1 nm to 400 nm, and has a relatively high energy. When directly irradiated onto the cell membrane of the microorganism, the ultraviolet ray destroys the cell wall or cell membrane of the microorganism and prevents the growth of the microorganism. Have

Therefore, if the method of removing microorganisms with chemicals for the water supplied to the oil well is changed to the method of ultraviolet irradiation, microorganisms that have not reacted with chemicals must also pass through an ultraviolet lamp, so microorganisms can be removed. Higher efficiency, no chemicals harmful to the human body, safety of the environment and safety of the working environment are also enhanced. Operation costs are also used only by the electricity supplied to the lamp, except for the initial installation cost of UV lamps. This can be significantly reduced compared to the cost.

Existing crude oil recovery water treatment device, as shown in Figure 1, after filtering the seawater withdrawal is installed a water treatment device to directly put chemicals into the piping through which the seawater was removed to remove microorganisms in the water Water treatment apparatus for improving crude oil recovery according to the present invention, by irradiating ultraviolet light into the water to irradiate the microorganisms in the water by causing the photochemical reaction, sterilization, ozone and the like action on the microorganisms in the water It is sterilized to recover the waste heat of water.

In one embodiment of the present invention shown in Figure 2, a water treatment apparatus for treating the water to be injected into the oil well in order to improve the recovery of crude oil stored in the oil well, the chamber 300, ultraviolet irradiation device 400 and waste heat recovery Device 500.

The chamber 300 receives and stores the water to be injected into the oil well (the plant for recovering the crude oil of the present embodiment may be seawater which can be easily obtained at sea since it is illustrated as being installed at sea) and stores the stored water. Inject into the well.

The chamber 300 stores a certain amount of water for the continuous supply of stable water into the well.

The ultraviolet irradiation device 400 is a device for irradiating the ultraviolet light to the water stored in the chamber 300 to remove the microorganisms in the water, and the UV lamp is fixed in the chamber 300 to be in contact with the water supplied to the chamber 300 It is arranged up and down (or left and right) while maintaining a gap, and both ends of the ultraviolet lamp can be fixed in the chamber 300 by fixing means such as a frame.

Since the ultraviolet irradiation device 400 according to the present invention can recover the waste heat with the waste heat recovery device 500 to be described later, it is possible to prevent waste of energy even if the sterilization efficiency is increased by using a high power ultraviolet irradiation device.

As the ultraviolet lamp, a conventional ultraviolet tube may be used, or a plurality of ultraviolet tubes having different shapes or outputs may be appropriately disposed in the chamber 300.

Ultraviolet light has a short wavelength and thus has a weak penetrating power, and thus, the number of UV lamps should be sufficiently installed so that the microbial value in the chamber 300 may be lower than an appropriate level.

The capacity of the chamber 300 can be increased to increase the amount of water stored in the chamber 300, which increases the time the water stays in the chamber 300 to increase the time the water is irradiated with ultraviolet light, thereby It allows for more complete removal of aquatic microbes. However, since the ultraviolet irradiation device 400 also needs to be large, it is necessary to manufacture a chamber 300 having an appropriate capacity in consideration of cost.

It is preferable that the residence time of the water staying in the chamber 300 is uniform, and the uniform amount of ultraviolet rays are irradiated to the water by the ultraviolet tube so that a uniform degree of reaction occurs in the water.

In addition, in the chamber 300, the contaminants are transformed into other less contaminant materials or decomposed into small molecules by ultraviolet irradiation. In this process, solid materials may be precipitated. An outlet 310 such as a drain valve may be installed to remove solid materials.

The front of the chamber 300 may be provided with a first pump 100 so that water supplied from the outside (water intake source) can be smoothly supplied to the chamber 300, and a second pump is provided at the rear of the chamber 300. By installing the 200 may be able to smoothly supply the water in the chamber 300 irradiated with ultraviolet light to the oil well.

Since the second pump 200 is a device for smoothly supplying water irradiated with ultraviolet rays to an oil well, the second pump 200 may be installed on a topside of a platform installed at sea or may be installed on a seabed.

In particular, if the second pump 200 is installed on the sea floor, it will be possible to form a clearance in the upper structure of the platform, and reduce the load of the upper structure of the platform.

In the case of installing the second pump 200 on the seabed, it may be necessary to use a subsea injection pump that may be installed on the seabed instead of the general pump.

Waste heat recovery device 500 is installed in the rear end of the chamber 300 to recover the waste heat of water injected into the oil well from the chamber 300, to improve the energy efficiency of the water treatment device.

The surface temperature of the ultraviolet lamp constituting the ultraviolet irradiation device 400 uses a high power ultraviolet lamp to increase the sterilization efficiency, the surface temperature of such ultraviolet lamp is usually a high temperature (for example 600 ℃ ~ 900 ℃) bar, Waste heat is recovered from the hot water through the UV lamp to prevent energy waste.

The waste heat recovery apparatus 500 exchanges heat between the water transfer pipe 250 through which water injected into the oil well from the chamber 300 flows and the low temperature fluid pipe 650 through which the low temperature fluid flows. It absorbs the waste heat it has so that it can be transformed into hot fluid.

The low temperature fluid changed into a high temperature fluid may be stored in a separate tank 600 and supplied to various demand sources in the plant for oil recovery.

By using the waste heat recovery device 500, energy efficiency can be improved by absorbing the heat source that is discarded, and the cost of the oil recovery plant can be reduced by replacing the boiler for heating the low temperature fluid in the oil recovery plant. You can do it.

The low temperature fluid may be oil or water for hot water supply, and the waste heat recovery apparatus 500 may use low temperature oil or low temperature water as high temperature oil or hot water to be used in a plant for oil recovery. Make sure

In addition, the water treatment apparatus for crude oil water promotion according to the present invention may further include a filtration device (150).

Filtration device 150 may be installed between the first pump 100 and the chamber 300, the ultraviolet irradiation method of the water treatment method for crude oil recovery to increase the cost is low, the device is simple but in turbid water Since the efficiency is reduced, it is installed to improve the water quality.

That is, water may contain large or non-living organisms such as solids, algae, mud, and the like, which greatly reduces the removal efficiency of aquatic microorganisms by ultraviolet irradiation. Is to install an additional filtration device to remove large foreign objects.

Water transfer pipe 250 through which the water injected into the oil well flows between the intake source, the first pump 100, the filtration device 150, the chamber 300, the waste heat recovery device 500, the second pump 200, and the oil well. It allows water to be transferred, and general pipe, rubber hose, special material hose, etc. can be used.

In addition, another embodiment of the present invention shown in Figure 3, a water treatment method for treating the water to be injected into the oil well to improve the recovery of crude oil stored in the oil well, water supply step (S10), water storage step (S20) ), Ultraviolet irradiation step (S30), waste heat recovery step (S40), water injection step (S40).

Water supply step (S10) is to supply the water to be injected into the oil well to the chamber 300, the water storage step (S20) stores the water supplied to the chamber 300 for a predetermined time, ultraviolet irradiation step (S30) is ultraviolet Irradiating the ultraviolet light to the water stored in the chamber 300 by the irradiation apparatus 400, waste heat recovery step (S40) recovers the waste heat of the water irradiated with ultraviolet rays, water injection step (S40) Inject water into the well.

In addition, another embodiment of the present invention is a water treatment method for treating water to be injected into an oil well in order to improve the recovery of crude oil stored in the oil well, irradiated with ultraviolet light to the water to be injected into the oil well, irradiated with ultraviolet light A method of injecting water into an oil well after recovering waste heat from the wastewater is provided.

As mentioned above, the two embodiments of the invention are illustrated as being carried out at sea, so the water mentioned in the two embodiments would be preferably seawater that can be readily obtained at sea, and the waste heat recovered is cold oil or cold hot water. It can be delivered to the supply water so that it can be supplied to various demand sources in the plant for oil recovery.

In addition, the ultraviolet irradiation is to be made in the chamber 300 that the water to be supplied to the well can stay for a certain time to increase the removal efficiency of the microorganism and at the same time to ensure a stable and continuous supply of water irradiated with the UV well. Could be.

Naturally, the two embodiments of the method invention may be configured by additionally adding various devices constituting the above-described water treatment device invention, and the method invention will be implemented to have the same purpose and function.

Hereinafter, the operation of a water treatment apparatus and method for treating water to be injected into an oil well in order to promote recovery of crude oil stored in the oil well according to the present invention will be described.

First, the seawater is withdrawn by the first pump 100, and the withdrawn seawater is a large organism or mud, such as solids, algae, and the like, which may be included in the water to increase the microbial removal efficiency of ultraviolet rays. A filtration device is used to remove large non-living organisms.

The seawater that has passed through the filtration device 150 is collected in the chamber 300, which is a space for storing the water, and the microorganisms in the water are removed while staying in the chamber 300 by an ultraviolet lamp installed in the chamber 300.

The high temperature seawater from which the microorganisms are removed from the chamber 300 enters the waste heat recovery device 500 and exchanges heat with the low temperature fluid (oil or water) to change into a high temperature fluid, and is supplied to various demand destinations in the plant for crude oil recovery. do.

The treated seawater is again injected into the oil well by the second pump 200, and the seawater supplied to the oil well fills the bottom of the oil well, and as a result, the crude oil is pushed upward to the top of the oil well as a piston to recover crude oil. To make it possible.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention will be.

100: first pump 150: filtration device
200: second pump 250: water transfer pipe
300: chamber 310: outlet
400: ultraviolet irradiation device 500: waste heat recovery device
600 tank 650: low temperature fluid pipe
S10: water supply step S20: water storage step
S30: UV irradiation step S40: Waste heat recovery step
S50: water injection step

Claims

A water treatment apparatus for treating water to be injected into an oil well to improve recovery of crude oil stored in the oil well,
A chamber 300 for receiving and storing water to be injected into the well and injecting the stored water into the well;
An ultraviolet irradiation device 400 for irradiating ultraviolet rays to the water stored in the chamber 300; And
A waste heat recovery apparatus 500 installed at a rear end of the chamber 300 to recover waste heat of water injected into the well from the chamber 300;
Water treatment apparatus for crude oil recovery, characterized in that it comprises a.

The method according to claim 1,
The waste heat recovery device 500,
Heat exchange occurs between the water transfer pipe 250 through which water injected from the chamber 300 flows into the oil well and the low temperature fluid pipe 650 through which the low temperature fluid flows so that the low temperature fluid recovers waste heat of the water;
Water treatment apparatus for improving crude oil recovery.

The method according to claim 2,
The low temperature fluid is water for oil or hot water supply;
Water treatment apparatus for improving crude oil recovery.

The method according to any one of claims 1 to 3,
A filtration device (150) installed at the front end of the chamber (300);
Water treatment apparatus for crude oil recovery further comprising a.

The method of claim 4,
An outlet 310 disposed at a lower end of the chamber 300 to discharge the precipitate;
Water treatment apparatus for crude oil recovery further comprising a.

A water treatment method for treating water to be injected into an oil well to improve recovery of crude oil stored in the oil well,
A water supply step of receiving water to be injected into the oil well into the chamber 300 (S10);
A water storage step (S20) of storing the water supplied to the chamber 300 for a predetermined time;
UV irradiation step (S30) for irradiating the ultraviolet light to the water stored in the chamber 300 by the ultraviolet irradiation device (400);
Waste heat recovery step (S40) for recovering the waste heat of the water irradiated with ultraviolet rays; And
A water injection step of injecting UV-irradiated water into the oil well (S40);
Water treatment method for crude oil recovery, characterized in that it comprises a.

A water treatment method for treating water to be injected into an oil well to improve recovery of crude oil stored in the oil well,
Irradiating ultraviolet light to water to be injected into the oil well, recovering waste heat from the water irradiated with ultraviolet light, and then injecting water into the oil well;
Water treatment method for improving crude oil recovery.

The method according to claim 6 or 7,
The waste heat is recovered by being transferred to low temperature oil or low temperature hot water supply water and supplied to a demand destination;
Water treatment method for improving crude oil recovery.

The method according to claim 8,
The ultraviolet irradiation is made in the chamber 300 in which water to be supplied to the well can stay for a predetermined time;
Water treatment method for improving crude oil recovery.