JPH11244667A - Crude oil treating device and treatment of crude oil using the device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a dehydrated oil low in water content and not contg. a muddy component by separating and removing the water in a crude oil to a high degree regardless of the properties of oil and to increase the throughput even with a small-sized equipment by improving the treating efficiency. SOLUTION: Crude oil is supplied into a treating tank 7 having a water discharge port 5 at the bottom, and a hollow-fiber membrane module 1 selectively permeable only to oil is dipped in the crude oil. A bubbler 4 is provided below the module 1 to generate a spiral flow in the tank 7, the crude oil in the tank 7 is heated by a heater 6 and heat-insulated, and the dehydrated oil permeated through the module 1 is sucked by a pump 8. The water (separated water layer 10) is discharged from the water discharge port 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an apparatus and a method for separating water in crude oil using a membrane.

[0002]

2. Description of the Related Art Liquid hydrocarbons produced from oil reservoirs on the earth are called crude oils. These liquid hydrocarbons are mainly composed of paraffinic, naphthenic and aromatic hydrocarbons. The physical and chemical properties of crude oil are determined by the composition ratio of various compounds contained in it,
In fact, the properties of crude oil vary considerably between oil fields and strata. Conventionally, in order to produce oil, first, crude oil is recovered from each part of the earth's oil reservoir through a production well by a method such as self-injection, pump oil extraction, or water or gas injection. The recovered crude oil is sent from a branch pipe called a Christmas tree at each well to a refinery through a pipeline buried underground. The crude oil collected at the oil refinery is sent to a separator (separator), where gas and moisture are separated from the crude oil.

FIG. 6 shows an example of a separator. The separator is roughly classified into a horizontal type, a vertical type, and a spherical type according to its shape, and this example is a horizontal type. The separator 201 of this example is composed of a sealed tank, and has a crude oil inlet 202 slightly above the center of the one side wall, and has a separated oil outlet 213 slightly below the center of the other side wall. A separation water outlet 212 is provided at the bottom and a gas outlet 214 is provided at the top. In the separator 201, a dam plate 203 is provided near the crude oil inlet 202 for suppressing the ripple of the inflowing crude oil.
The partition plate 215 is provided so that only the supernatant (separated oil) of the liquid 04 flows out to the separated oil layer 206 on the side of the separated oil outlet 213.

[0004] In order to remove water from crude oil using the separator 201 having such a structure, first, crude oil sent from a production well is passed through a crude oil inlet 202 through a separator 2.
After abruptly flowing into the inside of the fuel tank 01 and suppressing the undulation near the crude oil inlet 202, it flows over the weir plate 203 to the crude oil layer 204 which is the next section. The gas generated from the crude oil layer 204 is stored in the gas layer 205 inside the separator 201,
The gas is appropriately discharged from the gas outlet 214. The crude oil layer 204
Is separated into oil and water due to a difference in specific gravity with the passage of time, and the water is stored in a separated water layer 207 below. At this time, by heating the crude oil to 40 to 60 ° C., the viscosity of the crude oil is reduced, and the separation performance is improved. Separated water layer 2
The water 07 is controlled by the water level control device 208, and is appropriately sent out from the separated water outlet 212 by opening and closing the water level control valve 210. The separated oil from which the gas and moisture have been separated from the crude oil layer 204 in this way flows over the partition plate 215 and flows into the separated oil layer 206. This separated oil layer 2
06 separated oil is controlled by the oil level controller 209,
Opening and closing of the oil level control valve 211 causes the separated oil outlet 21
3 is sent out as appropriate.

[0005]

However, in the method of separating and removing water from crude oil by using the separator (separator) 201 as described above and utilizing the difference in specific gravity between oil and water, In order to increase the amount of equipment, the equipment must be enlarged, problems with the installation location of the equipment,
Problems such as capital investment cost and heating boiler energy cost arise. In addition, there are also problems such as the limit of processing speed and processing capacity, and the limit of moisture reduction,
It is not easy to enlarge the equipment and increase the throughput of crude oil.

[0006] By the way, even in the separated oil from which the gas and the water are separated and removed in this way, depending on the properties of the crude oil, fine water droplets and muddy water are uniformly dispersed and contained. Often the rate is high. Such a dispersed state is called an emulsion. Normally, it is impossible to expect that such fine water droplets are aggregated to form separable moisture simply by leaving them alone. this is,
This is because the interfacial tension of the water droplets in the crude oil is large, and the water droplets do not easily coalesce. In addition, since it contains sludge, there is a risk of corrosion in the processing equipment after separation, and in addition, the composition may be unsuitable for purification or production, in which case there is a problem that the yield is reduced. Was.

Therefore, as a method for lowering the water content of the separated oil, a method of artificially destroying an adsorbing film of water droplets using a surfactant or the like and combining the water droplets in an emulsion state into water that can be separated is used. Has been adopted. Alternatively, when a high-voltage alternating current of 10,000 to 20,000 volts is applied to the water droplet emulsion, the adsorption film of the water droplet changes its arrangement under the influence of the electric field, and the frequency of collision increases, and at the same time, it attracts each other. A method has also been adopted in which water droplets in an emulsion state are combined into water that can be separated. However, when adding a surfactant, it is necessary to select the optimal surfactant corresponding to the oil temperature, oil processing speed, oil components, and the salt concentration in the oil, and to study the injection conditions. is there. Surfactants are also subject to strong restrictions on salinity in oil or water.
There was a disadvantage that the use conditions had to be examined for each stratum. When applying a high-voltage alternating current, the equipment installation location, capital investment costs,
There were problems such as fire prevention measures and power supply methods.

The present invention has been made in view of the above-mentioned circumstances, and enables the water in the crude oil to be separated and removed to a high degree irrespective of the properties of the crude oil without adding a surfactant or applying a high-voltage current. To obtain a dehydrated oil with a low water content, improve the processing efficiency, and increase the throughput even with a small facility, and obtain a dehydrated oil that does not contain mud. The purpose is to do so.

[0009]

In order to solve the above-mentioned problems, a crude oil treatment apparatus of the present invention is provided with a membrane for selectively permeating oil in crude oil in a treatment tank having a drain port at a lower part thereof,
And a means for sucking dehydrated oil permeated through the membrane. Preferably, the film is a hydrophobic film. As the membrane, at least one selected from the group consisting of a hollow fiber membrane, a flat membrane, and a tubular membrane is preferably used. As the membrane, a hollow fiber membrane module in which a plurality of hollow fiber membranes are arranged substantially in parallel, and an oil collecting pipe communicating with the inside of the hollow fiber membrane is fixed to at least one end of the hollow fiber membrane in a liquid-tight manner. Preferably, the oil collecting pipe is connected to the suction means. It is preferable that the film is detachably mounted in the processing tank. As the suction unit, at least one selected from the group consisting of a pump, a suction unit using the principle of siphon, and a suction unit using a water level difference is preferably used. It is preferable to provide a bubble flow generator below the film in the processing tank. It is preferable to provide a means for heating and keeping the inside of the processing tank. It is preferable that the film is movably mounted in the processing tank and a driving means for moving the film is provided.

[0010] Further, the crude oil treatment method of the present invention uses the crude oil treatment apparatus of the present invention to supply crude oil into the treatment tank, immerse the membrane in the crude oil, and remove dehydrated oil that has passed through the membrane. It is characterized in that, while being sucked and taken out, the water separated from the crude oil is drained from the drain port. The suction of the dehydrated oil is preferably performed intermittently.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
1 and 2 show one embodiment of the crude oil treatment apparatus of the present invention. FIG. 1 is a schematic configuration diagram of the apparatus, and FIG. 2 is a perspective view of a hollow fiber membrane module. The crude oil treatment device shown in FIG. 1 includes a treatment tank 7 having a drain port 5 at a lower portion, a hollow fiber membrane module 1 disposed in the treatment tank 7, and a pump 8 connected to the hollow fiber membrane module 1. A bubble flow generator 4 provided below the hollow fiber membrane module 1 in the processing tank 7, a blower 9 connected to the bubble flow generator 4,
And a heating device 6 provided on the outside.

As shown in FIG. 2, the hollow fiber membrane module 1 comprises a screen portion 2a in which a plurality of hollow fiber membranes 2 are arranged substantially in parallel, and oil collecting tubes 3, 3 fixed to both ends thereof. ing. The hollow fiber membrane 2 is a porous hollow fiber, and its surface characteristics are preferably hydrophobic. For example, in the case of a hollow fiber membrane made of a hydrophobic polymer or a hollow fiber membrane made of a hydrophilic polymer, those having a hydrophobic function on the surface thereof are preferably used. When the surface of the hollow fiber membrane 2 is hydrophobic, the oil component in the crude oil is hydrophobic, so that the hollow fiber membrane 2
And the water in the crude oil repels water on the membrane surface and cannot pass through the hollow fiber membrane 2, so that the oil-water separation in the crude oil can be performed efficiently. Examples of the material of the hollow fiber membrane 2 include polyethylene, polypropylene, polysulfone, polytetrafluoroethylene (Teflon),
Polycarbonate, polyester, cellulose,
Polyamide-based, aromatic polyamide-based, polyacrylonitrile-based, polymethylmethacryl-based, polyvinyl alcohol-based, ethylene-vinyl alcohol copolymer, polyether-based, and the like can be used. If the surface characteristics of the hollow fiber membrane 2 are water repellent, the moisture content of the oil (hereinafter, referred to as “dehydrated oil”) permeating the hollow fiber membrane 2 can be further reduced, which is preferable. For example, by coating the surface of the hollow fiber membrane 2 with a fluororesin, the surface of the hollow fiber membrane 2 can be made water-repellent.

The inner and outer diameters and the thickness of the hollow fiber membrane 2 are preferably 2000 μm or less in outer diameter, 1800 μm or less in inner diameter, and 200 μm or less in film thickness, more preferably 600 μm in outer diameter.
m, the inner diameter is 400 μm or less, and the film thickness is 100 μm or less. The moisture content of the dehydrated oil can be controlled by selecting the pore size of the hollow fiber membrane 2 which is a porous membrane, and the moisture content of the dehydrated oil decreases as the pore size decreases. Generally, it is considered that the water content of the dehydrated oil is preferably 2.0% or less. Preferably, if the pore diameter of the hollow fiber membrane 2 is 1.0 μm or less, not only the water in the crude oil but also the water droplet emulsion can be separated and removed, so that the water content of the dehydrated oil measured by the Karl Fischer method is 2.0%. The pore diameter can be set to be equal to or less than 0.2 μm.
The porosity of the hollow fiber membrane 2 is desirably 20 to 90%. Also, the longer the length of the hollow fiber membrane 2 constituting the hollow fiber membrane module 1 can be, the larger the area of the screen portion 2a can be. However, if the length is too long, the suction efficiency deteriorates.
It is preferable to set within the range of about m to 2000 mm according to the properties of the crude oil to be treated. The number of the hollow fiber membranes 2 constituting the hollow fiber membrane module 1 depends on the area of the screen portion 2a and the total surface area of the hollow fiber membrane 2, so that the processing capacity of the apparatus changes. It is designed according to the requirements.

The oil collecting tubes 3 and 3 are formed in a tubular shape through which dehydrated oil flows, and have a dehydrated oil outlet 3a formed at an end thereof. As the material of the oil collecting pipes 3, 3, those having excellent mechanical strength and durability and having corrosion resistance to dehydrated oil are preferably used. For example, polyethylene resin, polypropylene resin, polyacetal resin, vinyl chloride resin, polyamide resin, PBT resin and the like can be mentioned. In the present embodiment, the oil collecting pipes 3 and 3 are formed to have a circular cross section. However, the present invention is not limited to this, and a pipe having an arbitrary shape can be used. Then, the end portions on both sides of a large number of hollow fiber membranes 2 arranged in a screen shape are inserted into slits (not shown) formed on the side surfaces of the oil collecting tubes 3 and 3, and the fixing members are filled therein. The hollow fiber membrane 2 and the oil collecting pipes 3, 3 are fixed in a liquid-tight manner. In this state, the inside of the oil collecting tubes 3 and 3 communicates with the inside of the hollow fiber membrane 2. The fixing member fixes each end of the large number of hollow fiber membranes 2 to the oil collecting pipe 3 while maintaining the open state. For example, a liquid resin such as an epoxy resin, an unsaturated epoxy resin, or a polyurethane resin is used. A cured product, a product obtained by melting and cooling and solidifying a polyolefin or the like can be used. The fixing of the hollow fiber membrane 2 is not limited to both ends but may be only one end. And when fixing only one end to the oil collecting pipe 3,
The other end not fixed to the oil collecting pipe 3 needs to be sealed so that untreated crude oil does not flow from the open end of the hollow fiber membrane 2. Alternatively, the hollow fiber membrane 2 may be U-shaped and fixed only at one end.

The dewatered oil outlet 3a of the oil collecting pipes 3, 3 is
For example, it is connected to a suction means such as a pump 8, and dehydrated oil that has passed through the hollow fiber membrane 2 among the crude oil in the processing tank 7 passes through the inside of the hollow fiber membrane 2 and the inside of the oil collecting pipe 3 to the outside of the processing tank 7. It is configured to be sucked. As the pump 8,
Explosion-proof pumps are used, and are roughly classified into reciprocating pumps (quantitative pumps) and rotary pumps (rotary pumps). Examples of the reciprocating pump include a piston pump, a diaphragm pump, and a wing pump, and examples of the rotary pump include a gear pump, an eccentric pump,
And a screw pump. Known materials such as a metal pump, a lining pump, a resin pump, and a porcelain pump can be used as the material. Since these pumps have different working principles, structures, characteristics, and the like depending on the type, it is preferable to select them according to the properties and processing amount of crude oil to be treated.

Further, suction means other than the pump can be used. For example, a liquid level in the processing tank 7 and a dehydrated oil tank (not shown) in which dehydrated oil taken out from the oil collecting pipe 3 is stored.
It is also possible to use a means for suctioning by making use of a difference in water level between the two tanks by providing a difference between the liquid level in the tank and a means for sucking using, for example, the principle of siphon. The use of a pump as the suction means is advantageous in reducing the size of the treatment apparatus, and the use of a suction means utilizing the difference in water level or a suction means utilizing the principle of siphon eliminates the need for a power source and reduces operating costs. However, it is advantageous in that it is cheaper.

The hollow fiber membrane module 1 is preferably removably mounted in the processing tank 7. For example, the hollow fiber membrane module 1 may be suspended from above, or the hollow fiber membrane module 1 may be provided with a floating float or the like. It is preferable to attach by a method of floating support. It is convenient to use a coupler to make the hollow fiber membrane module 1 detachable. If the hollow fiber membrane module 1 is made detachable, the hollow fiber membrane module 1 can be easily replaced, and maintenance is very simple. In the present embodiment, the hollow fiber membrane module 1 is placed in the processing tank 7 such that the direction along the surface of the screen portion 2a and the length direction of the oil collecting pipe 3 are vertical (perpendicular to the liquid surface). Is located at
Not limited to this, the properties of the crude oil to be treated, the flow direction of the crude oil in the treatment tank 7, the required treatment speed, the flow rate, the treatment tank 7
In consideration of the structure described above, it can be arranged vertically, horizontally, or obliquely with respect to the horizontal or vertical direction. Further, the number of the hollow fiber membrane modules 1 arranged in the treatment tank 7 is not limited to one, and a plurality of hollow fiber membrane modules 1 are arranged.
By disposing, the total surface area of the film can be increased to increase the processing capacity. For example, a plurality of hollow fiber membrane modules 1 may be stacked. In this case, it is preferable that a plurality of hollow fiber membrane modules 1 be simultaneously sucked by the suction means 8. Further, it is preferable that a plurality of hollow fiber membrane modules 1 be unitized by being housed in one frame, for example, because attachment and detachment into the processing tank 7 becomes easy. In particular, if the unit is formed using a coupler, the maintenance is very simple.

FIGS. 3 and 4 show examples of a hollow fiber membrane unit 11 in which eight hollow fiber membrane modules 1 are unitized. FIG. 3 is a front view, and FIG. 4 is IV-IV in FIG. It is sectional drawing which follows a line. In these drawings, the same members as those in FIG. 1 are denoted by the same reference numerals. The hollow fiber membrane unit 11 includes two plate-shaped side plates 1 arranged in parallel.
Two large oil collecting pipes 1 parallel to each other at the four corners of 5, 15
2, 12 and two support tubes 14, 14 are fixed at both ends to form a box-shaped frame, and eight hollow fiber membrane modules 1, 1,... It is freely attached and configured roughly. That is, the eight hollow fiber membrane modules 1, 1...
And the screen surfaces 2a, 2a are arranged in parallel with each other, the upper ends of the eight oil collecting tubes 3, 3 at one end are connected to one large oil collecting tube 12, and the eight oil collecting tubes 12 at the other end are arranged. Is connected to the other large oil collecting pipe 12. As a result, the large oil collection pipe 12 and the oil collection pipe 3 are in communication. The lower end of the oil collecting pipe 3 is fixed to a support pipe 14 provided in parallel with the large oil collecting pipe 12. The lower end of the oil collecting pipe 3 is sealed, and the supporting pipe 14 is provided with an insertion hole only,
The support pipe 1 in a guide state in which the lower end of the oil collection pipe 3 is inserted here
It may be four. Each large oil collecting pipe 12 is provided with a dehydrated oil take-out pipe 13.
3 is connected to a suction means such as a pump 8. When such a hollow fiber membrane unit 11 is used, the dehydrated oil that has passed through the hollow fiber membrane 2 is taken out of the treatment tank 7 through the oil collecting pipe 3, the large oil collecting pipe 12, and the dehydrated oil take-out pipe 13. .

The bubble flow generator 4 includes the hollow fiber membrane module 1
Is connected to a blower 9 for supplying gas. Bubbles are generated from an arbitrary direction of the foam flow generator 4, and as a result, the crude oil in the treatment tank 7 has a screen portion 2 a as shown by an arrow in FIG.
A swirling flow is generated from the bottom to the top along the surface and from the top to the bottom between the hollow fiber membrane module 1 and the inner wall of the processing tank 7. Therefore, regardless of the properties of the crude oil, the efficiency of the separation treatment on the surface of the hollow fiber membrane 2 can be further improved, and clogging of the pores of the hollow fiber membrane 2 can be reduced. In designing the apparatus, the hollow fiber membrane module 1 is designed so that the above-mentioned swirling flow occurs efficiently.
It is preferable to form a sufficient space for a downward flow to be formed in the upper, lower, left, and right directions, so that an upward flow is ensured in the vicinity of the screen portion 2a. Although not shown, the bubble flow generating device 4 prevents bubbles generated from the bubble flow generating device 4 from escaping outward, that is, between the hollow fiber membrane module 1 and the inner wall of the treatment layer 7 and disturbing the flow of crude oil. A shielding plate may be provided between 4 and the hollow fiber membrane module 1. Bubble flow generator 4
Are the positions of the holes where the bubbles are generated, the positional relationship between the bubble flow generator 4 and the hollow fiber membrane module 1 so that the bubbles are evenly and efficiently applied to the surface of the screen portion 2a of the hollow fiber membrane module 1, and It is preferable to select the amount of generated bubbles and the like according to the properties of the crude oil to be treated. The gas used preferably has little effect on the crude oil to be treated. For example, air, carbon dioxide gas, nitrogen gas, liquefied petroleum gas (LPG) and the like can be generally used.

The hollow fiber membrane module 1 is placed in the treatment tank 7.
Is also preferable, which is effective for further improving the efficiency of the separation treatment on the surface of the hollow fiber membrane 2 irrespective of the properties of the crude oil and at the same time reducing the clogging of the pores of the hollow fiber membrane 2. In particular, it is more preferable to drive the hollow fiber membrane module 1 at the same time as generating the flow in the crude oil as described above. For example, the hollow fiber membrane module 1 may be movably mounted in the treatment tank 7 and an appropriate driving means may be provided so that the hollow fiber membrane module 1 can be moved and rotated in appropriate directions such as up, down, left, and right. Alternatively, in order to swing or vibrate the hollow fiber membrane module 1, a drive means such as an eccentric cam, an ultrasonic vibration device, or a vibrator may be appropriately provided.

Outside the processing tank 7, a heating device 6 for heating or keeping the temperature of the crude oil in the processing tank 7 is provided. Thereby, the viscosity of the crude oil is reduced by heating and keeping the crude oil in the treatment tank 7 at an appropriate temperature, so that the separation efficiency by the hollow fiber membrane module 1 is improved regardless of the properties of the crude oil, and water droplets due to heat are generated. This is preferable because it promotes the destruction of the emulsion and separates water from crude oil. Examples of preferable heating devices include heating devices such as a steam pipeline, an oil jacket, a hot water circulation device, and an electric heater coil. If the heating temperature is too high, the generation of vaporized substances (gas) increases, and if the heating temperature is too low, the viscosity of the crude oil increases and the separation efficiency decreases, so that the temperature is preferably 30 ° C to 80 ° C, more preferably 40 ° C to 60 ° C. Is set in the range.

In order to carry out the water separation treatment of crude oil using such a crude oil treatment apparatus, first, crude oil is supplied into the treatment tank 7 and the hollow fiber membrane module 1 is immersed in this crude oil. Next, the pump 8 connected to the oil collecting pipe 3 of the hollow fiber membrane module 1 is driven to perform suction. At the same time, it is preferable to supply gas from the blower 9 to the bubble flow generator 4 to perform bubbling below the hollow fiber membrane module 1. Further, it is preferable to heat the crude oil in the treatment tank 7 to an appropriate temperature by the heating device 6 and keep the temperature. The suction by the pump 8 is preferably performed intermittently.
It is preferable to repeat the operating condition of stopping for 2 minutes after suctioning for 2 minutes.

As a result, of the crude oil, an oil component (dehydrated oil) that can pass through the hollow fiber membrane 2 is taken out of the treatment tank 7 through the hollow fiber membrane 2 and the oil collecting pipe 3. On the other hand, the water in the crude oil cannot permeate through the hollow fiber membrane 2 and settles down with the lapse of time due to the difference in specific gravity, forming a separated water layer 10 at the lower part of the treatment tank 7. You only have to drain. Also, mud in crude oil cannot pass through the hollow fiber membrane 2 and settles by gravity, so that it can be discharged from the drain port 5 together with the water in the separated water layer 10. Natural gas dissolved in crude oil passes through the hollow fiber membrane 2 and is taken out together with dehydrated oil. This natural gas can be supplied to the bubble flow generator 4 and reused as bubbling gas. This is advantageous in reducing operating costs.

When the suction by the pump is performed intermittently,
When continuous suction is performed, it is preferable to prevent excessive filtration turbidity from being deposited near micropores on the surface of the hollow fiber membrane 2. That is, the bubbles generated from the bubble flow generator 4 during the stoppage time of the suction play the role of cleaning the surface of the hollow fiber membrane 2, and the deposited solids diffuse to return the membrane surface to a clean state. Therefore, since the surface of the hollow fiber membrane 2 can be kept clean without the need for backwashing, there is an advantage that maintenance equipment and work can be reduced.

As described above, according to the method for treating crude oil using the apparatus of the present embodiment, water can be highly separated and removed from crude oil irrespective of the properties of crude oil, and sludge can also be separated and removed. Thus, a dehydrated oil having a low moisture content and containing no mud is obtained. In addition, since the crude oil is forcibly filtered by performing suction through the hollow fiber membrane 2, the treatment can be efficiently performed without waiting for the sedimentation of water due to the difference in specific gravity as in the related art. Therefore, it is possible to process a large amount of crude oil with a small device. In this embodiment, since the hollow fiber membrane 2 is used, the membrane area per unit volume, which is effective for filtering crude oil, is large, and the processing efficiency is good. Further, since the plurality of hollow fiber membranes 2 are used in the form of a module, the handling of the hollow fiber membranes 2 is easy.

In the above embodiment, the membrane module composed of the hollow fiber membrane 2 is used. However, the membrane module may be configured to have a membrane that selectively permeates only the oil component and to suck the dehydrated oil that has permeated through the membrane. A porous membrane other than the hollow fiber membrane 2 may be used. The porous film used preferably has a surface property of hydrophobic or water repellent. Examples of the porous membrane other than the hollow fiber membrane 2 include porous ceramics such as SiC, carbon, alumina, activated alumina, glass, cordierite, mullite, lithium aluminum silicate, and aluminum titanate;
There are porous powder sintered bodies such as i, Cu, Al, Ti, Fe, Co and alloys thereof. Further, it is preferable to perform a water repellent treatment on these porous bodies, for example, using a water repellent such as a silicone resin, an acrylic resin, a polyethylene resin, a fluororesin, and various coupling agents, and diluting the water repellent with a solvent. The porous body may be immersed in a liquid, an emulsion, or a liquefied gas dispersion and dried. Alternatively, as the porous membrane, a sintered compact such as a powder of a fluorine resin, a polyethylene resin, a polypropylene resin, and an acrylic resin can be used. This sintered compact is heated by filling the powder into a mold having a space of the desired shape and heating the mold to a temperature equal to or higher than the melting temperature of the resin, or by supplying the powder into a sheet having a constant thickness. By passing through a furnace, the contact between the powder particles is fused, and then
Obtained by cooling.

As the form of the porous membrane, for example, a flat membrane may be used, and a flat membrane element 22 as shown in FIG. 5 and a flat membrane unit 21 obtained by laminating a plurality of these elements can be used. The flat membrane element 22 of this example includes two flat membranes 2.
3 are arranged in parallel, one side of the hollow portion between them is communicated with the oil collecting pipe 25, and the other three sides are sealed. The oil collecting pipe 25 is provided with a dehydrated oil outlet 24, and the dehydrated oil outlet 24 may be connected to a suction means such as a pump. The flat membrane unit 21 is formed by stacking seven such flat membrane elements 22 and stacking the flat membranes 23 in parallel. Alternatively, it is also possible to adopt a configuration in which a hollow portion is suctioned using a tubular membrane. As described above, even when the flat membrane 23 or the tubular membrane is used, the water separation treatment of the crude oil can be performed highly and efficiently, as in the case where the hollow fiber membrane module 1 is used. In particular, in the case of a flat film, there is an advantage that the film surface can be easily cleaned and is suitable for mass production of modules.

[0028]

EXAMPLES Hereinafter, the effects of the present invention will be clarified by showing specific examples. (Example 1) A treatment for separating oil and water from crude oil (light oil) was performed using the crude oil treatment apparatus of the present invention. The hollow fiber membrane 2 is made of polyethylene and has an average pore diameter of 0.1 μm, a porosity of 72%, an inner diameter of 360 μm, and a film thickness of 90 μm.
This was arranged in parallel, in the form of a screen, and both ends were adhered and fixed with an epoxy potting agent and then opened, and both open ends were fixed so as to communicate with the oil collecting pipe 3. A hollow fiber membrane module 1 (effective length 800 mm, membrane area 4 m ² ) was produced. This hollow fiber membrane module 1 is
This is used to form a hollow fiber membrane unit 11 as shown in FIGS. 3 and 4, which is disposed in the treatment tank 7,
Bubble flow generator 4 was arranged below it. And processing tank 7
Crude oil (light oil, water content 20%) was supplied into the reactor, and the crude oil was heated and kept warm at 60 ° C. Next, the pump 8 connected to the hollow fiber membrane module 1 was operated to perform suction. At the same time, air was sent from the blower 9 to the bubble flow generator 4 to perform bubbling below the hollow fiber membrane module 1. The gas supply amount at this time is 50 Nm ³ per horizontal cross-sectional area of the hollow fiber membrane module 1.
/ M ² · h. Crude oil processing was performed by continuously performing suction with the pump 8 for 100 hours, and the filtration differential pressure, the moisture content of the obtained dehydrated oil, and the filtration flow rate at the start and end of the processing were examined. The results are shown in Table 1 below. The moisture content was measured by a micro moisture analyzer, CA-06, manufactured by Mitsubishi Chemical Corporation.
(Karl Fischer method).

Example 2 In Example 1, the hollow fiber membrane 2 was made of polypropylene and had a mean pore diameter of 0.04 μm, a porosity of 49%, an inner diameter of 200 μm, and a KPF 190M (commercially available) having a thickness of 22 μm. Name, Mitsubishi Rayon
A crude oil treatment device was configured and treated with crude oil in the same manner except that the above-mentioned method was used. As in Example 1, the filtration pressure difference, the water content of the obtained dehydrated oil, and the filtration flow rate at the start and end of the treatment were examined. The results are shown in Table 1 below.

[0030]

[Table 1]

From the results of Example 1 and Example 2,
The filtration differential pressure at the start and end of the treatment is small, the moisture content of the dehydrated oil is as small as 0.2% and 0.02%, and the value of this moisture content varies between the start and the end of the treatment. Did not. Also, the filtration flow rate did not change between the start of the treatment and the end of the treatment. From this, it was recognized that the water in the crude oil could be highly separated and removed without using a surfactant or the application of a high voltage, and that the operation could be stably performed for a long time.

[0032]

As described above, the crude oil treatment apparatus of the present invention is an apparatus for separating and removing water in crude oil, and selectively permeates oil in crude oil into a treatment tank having a drain port at the bottom. And a means for sucking dehydrated oil permeated through the membrane. Further, the method for treating crude oil of the present invention uses the crude oil treatment apparatus of the present invention, supplies crude oil into the treatment tank, immerses the membrane in the crude oil, and sucks dehydrated oil that has passed through the membrane. And the water separated from the crude oil is drained from the drain port. ADVANTAGE OF THE INVENTION According to this invention, the water | moisture content can be highly separated and removed from crude oil irrespective of the property of crude oil, and muddy can also be separately removed. Accordingly, a dehydrated oil having a low moisture content and containing no mud can be obtained without using a surfactant or applying a high voltage. Further, by performing suction through the membrane, processing can be performed efficiently without waiting for sedimentation of water due to a difference in specific gravity as in the related art. Therefore, it is possible to process a large amount of crude oil with a small device.

When a hydrophobic membrane is used as the membrane, the oil component in the crude oil easily passes through the membrane because it is hydrophobic, and the water in the crude oil repels water on the membrane surface. Can do well. The membrane is at least one selected from the group consisting of a hollow fiber membrane, a flat membrane, and a tubular membrane.
Species can be preferably used. When a hollow fiber membrane is used, the membrane area per unit volume, which is effective for filtering crude oil, is large and the treatment efficiency is good. The use of a flat membrane facilitates cleaning of the membrane surface, and is suitable for mass production of modules. As the membrane, a hollow fiber membrane module is used in which a plurality of hollow fiber membranes are arranged in parallel, and an oil collecting pipe communicating with the inside of the hollow fiber membrane is liquid-tightly fixed to at least one end of the hollow fiber membrane. ,
A configuration in which the oil collecting pipe is connected to the suction means can be preferably adopted. According to this configuration, since the plurality of hollow fiber membranes are modularized, handling of the hollow fiber membrane is easy. Further, by detachably mounting the film in the processing tank, replacement and maintenance of the film are facilitated.

As the suction means, at least one selected from the group consisting of a pump, a suction means using a siphon principle, and a suction means using a water level difference is preferably used. The pump is used for reducing the size of the processing apparatus. The suction means utilizing the difference in water level and the suction means utilizing the principle of siphon are advantageous in that they do not require a power source and can be operated at low cost. By providing a bubble flow generator below the membrane in the treatment tank, a swirling flow that flows from above to below near the surface of the membrane can be generated. Can be further improved, and clogging of the pores of the membrane can be reduced. By providing a means for heating and keeping the inside of the treatment tank, while reducing the viscosity of the crude oil in the treatment tank and improving the separation efficiency by the membrane, promoting the destruction of the water droplet emulsion by heat,
It is also preferable because water separation from crude oil also occurs. By movably mounting the membrane in the treatment tank and providing a driving means for moving the membrane, the membrane can be driven during the filtration process, and the separation treatment efficiency on the membrane surface can be further improved. This is advantageous in that clogging of the pores of the membrane is reduced. If the suction of the dehydrated oil is performed intermittently, it is preferable to prevent excessive deposition of filtration suspended matter in the vicinity of the fine pores on the surface of the membrane when continuous suction is performed. There is an advantage that can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an example of a crude oil treatment device of the present invention.

FIG. 2 is a perspective view of a hollow fiber membrane module used in the apparatus of FIG.

FIG. 3 is a front view showing an example of a hollow fiber membrane unit.

FIG. 4 is a cross-sectional view of the hollow fiber membrane unit of FIG.

FIG. 5 is a perspective view showing an example of a flat membrane unit.

FIG. 6 is a schematic configuration diagram showing a separator used for conventional crude oil processing.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1: Hollow fiber membrane module, 2: Hollow fiber membrane, 3: Oil collecting pipe,
4: foam flow generator, 5: drain port, 6: heating device, 7: treatment tank, 8: pump (suction means)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B01D 17/022 502 B01D 17/022 502D 502B 63/02 63/02 65/00 65/00 65/02 520 65/02 520 C10G 31/09 C10G 31/09

Claims (11)

[Claims] 1. A device for separating and removing water in crude oil, wherein a membrane for selectively permeating oil in crude oil is disposed in a treatment tank having a drainage port at a lower part, and dehydration permeating through the membrane is provided. A crude oil treatment device comprising means for sucking oil. 2. The crude oil treatment device according to claim 1, wherein said membrane is a hydrophobic membrane. 3. The crude oil treatment device according to claim 1, wherein the membrane is at least one selected from the group consisting of a hollow fiber membrane, a flat membrane, and a tubular membrane. 4. A plurality of hollow fiber membranes are arranged substantially in parallel as the membrane, and an oil collecting pipe communicating with the inside of the hollow fiber membrane is fixed to at least one end of the hollow fiber membrane in a liquid-tight manner. The crude oil processing apparatus according to claim 1, wherein the oil collecting pipe is connected to the suction means using a hollow fiber membrane module. 5. The crude oil treatment device according to claim 1, wherein the membrane is detachably mounted in the treatment tank. 6. The suction device according to claim 1, wherein the suction device includes at least one selected from the group consisting of a pump, a suction device using a siphon principle, and a suction device using a water level difference. Crude oil processing equipment. 7. The crude oil treatment device according to claim 1, further comprising a bubble flow generator under the membrane in the treatment tank. 8. The crude oil treatment apparatus according to claim 1, further comprising means for heating and keeping the temperature in the treatment tank. 9. The crude oil treatment apparatus according to claim 1, wherein the membrane is movably mounted in the treatment tank, and comprises a driving means for moving the membrane. 10. Using the apparatus according to any one of claims 1 to 9, supplying crude oil into the treatment tank,
A method for treating crude oil, comprising immersing the membrane in the crude oil, sucking out the dehydrated oil that has passed through the membrane, and draining the water separated from the crude oil from the drain port. 11. The crude oil processing method according to claim 10, wherein the suction of the dehydrated oil is performed intermittently.