CN111303931B

CN111303931B - Heavy dirty oil dehydration method

Info

Publication number: CN111303931B
Application number: CN201811513969.3A
Authority: CN
Inventors: 卢秋旭; 王阳峰; 吴振华; 高宏义; 李明一
Original assignee: China Petroleum and Chemical Corp; Sinopec Dalian Research Institute of Petroleum and Petrochemicals
Current assignee: Sinopec Dalian Petrochemical Research Institute Co ltd; China Petroleum and Chemical Corp
Priority date: 2018-12-12
Filing date: 2018-12-12
Publication date: 2021-07-09
Anticipated expiration: 2038-12-12
Also published as: CN111303931A

Abstract

The invention discloses a heavy dirty oil dehydration method, which comprises the following steps: feeding the heavy dirty oil into a flash tower for flash evaporation dehydration treatment, obtaining sewage containing light oil at the tower top, and obtaining dehydrated heavy dirty oil at the tower bottom; the pressure of the flash evaporation dehydration treatment is 0.40-0.65 MPaG, preferably 0.45-0.55 MPaG. The flash evaporation dehydration treatment temperature of the flash evaporation tower is 155-200 ℃. The method adopts a flash evaporation treatment mode, effectively removes water in the heavy dirty oil, and can be used as quenching oil for recycling or deep dehydration.

Description

Heavy dirty oil dehydration method

Technical Field

The invention relates to a heavy dirty oil dehydration method.

Background

The recycling of heavy dirty oil is always a difficult point for the production operation management of various oil refineries. The typical treatment for refineries is to sediment and dewater the heavy dirty oil and then blend it into the crude tank or into the coker for recycle as quench oil. The crude oil is increasingly poor in properties, such as poor thick oil, the density of the crude oil is generally 0.95-0.97, the crude oil has the characteristics of high salt content, high asphaltene content and low light oil content, the electric desalting device is difficult to operate, the salt content of the crude oil after final removal reaches 8-15 mg/L, and the content of electric desalting drainage oil is ultrahigh, so that the crude oil is also a main source for generating heavy dirty oil. The heavy dirty oil contains a large amount of oil-water emulsion, the emulsion exists in the forms of oil-in-oil, water-in-oil and the like, the emulsion is difficult to break, and the components are very complex. Meanwhile, the density of a part of heavy sewage components is higher than that of water, the density difference of water and oil is not obvious, and the heavy sewage components are difficult to be remilled by a settling dehydration method. Therefore, how to treat the heavy dirty oil is an important problem faced by the current oil refinery.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a heavy dirty oil dehydration method. The method adopts a flash evaporation treatment mode, effectively removes water in the heavy dirty oil, and can be used as quenching oil for recycling.

A heavy dirty oil dehydration method comprises the following steps: feeding the heavy dirty oil into a flash tower for flash evaporation dehydration treatment, obtaining sewage containing light oil at the tower top, and obtaining dehydrated heavy dirty oil at the tower bottom; the pressure of the flash evaporation dehydration treatment is 0.40-0.65 MPaG, preferably 0.45-0.55 MPaG. The flash evaporation dehydration treatment temperature of the flash evaporation tower is 155-200 ℃.

The flash evaporation dehydration treatment process is set to be 1-5 levels; and (3) after the heavy dirty oil is subjected to first-stage flash evaporation dehydration, the obtained dehydrated dirty oil enters the next-stage flash evaporation dehydration.

Preferably, the 3-stage flash dehydration is carried out as follows: the heavy dirty oil is heated to a certain temperature and then sent into a first-stage flash tower, the water-containing dirty oil at the bottom of the first-stage flash tower is heated to a certain temperature and then sent to a second-stage flash tower, the water-containing dirty oil at the bottom of the second-stage flash tower is heated to a certain temperature and then sent to a third-stage flash tower, the dehydrated heavy dirty oil is obtained at the bottom of the third-stage flash tower, and the light oil-containing sewage at the tops of the first, second and third-stage flash towers is cooled and then sent to a buffer tank for oil-water separation. The flash evaporation dehydration treatment temperature is as follows: the first stage is 155-200 ℃, preferably 155-165 ℃; the second stage is 155-200 ℃, preferably 165-175 ℃; the third stage is 155-200 ℃, preferably 175-185 ℃.

The heavy dirty oil is generally from tank bottom oil sludge generated in a tank cleaning process of an oil refinery, high-water-content dirty oil generated in an electric desalting and water cutting process of an atmospheric distillation device and dirty oil recovered from a sewage treatment plant, and the heavy dirty oil generally has the water content of 30-85% (m) and the salt content of 1000-3000 mg/L.

The feed inlet of the flash tower is located at 1/2-1/3, preferably 5/16-1/3 in height by height.

The height-diameter ratio of the flash tower is 80/5-80/8, preferably 80/5-80/7, and more preferably 80/6-80/7.

The heavy dirty oil obtained by the method of the invention is preferably sent into an oil-water separation device with the following structure for further dehydration treatment. The oil-water separation device comprises a pre-separation area, an upper coalescence-separation area and a lower coalescence-separation area; the pre-separation area comprises a feeding pipe, a hollow filter element and a stable flow area, the hollow filter element is arranged in the middle of the feeding pipe, and a feeding hole of the feeding pipe is communicated with the center of the hollow filter element or communicated with a space between the hollow filter element and the wall of the feeding pipe; the surface material of the hollow filter element is oleophylic hydrophobic material or hydrophilic oleophobic material, and the hollow filter element is communicated with the stable flow area; the upper part of the steady flow zone is connected with the upper coalescence-separation zone, and the upper coalescence-separation zone sequentially comprises a material uniform distributor I, an upper coalescence demulsification filler layer and an upper coalescence depth demulsification filler layer from bottom to top; the lower part of the steady flow area is connected with the lower coalescence-separation area, the lower coalescence-separation area sequentially comprises a material uniform distributor II, a lower coalescence-demulsification packing layer and a quick separation layer from top to bottom, and two ends of the upper coalescence-separation area and the lower coalescence-separation area are respectively provided with an outlet.

In the oil-water separation device, the feeding pipe is of a horizontal tubular structure, and the oleophylic and hydrophobic material is selected from at least one of polyester, polyethylene, polypropylene, polyvinyl chloride, polytetrafluoroethylene, acrylic acid and nylon, or is selected from a material with the surface subjected to oleophylic and hydrophobic treatment; when the oleophilic and hydrophobic material is selected, the material can absorb 20mL to 100mL of oil per gram calculated by weight; the hydrophilic and oleophobic material is selected from natural high molecular polymers with carboxyl, amino or hydroxyl on the main chain or side chain, such as polypropylene fiber, or from materials with hydrophilic and oleophobic treatment on the surface of the material; the fiber filaments prepared from the oleophilic and hydrophobic material or the hydrophilic and oleophobic material can also be added with materials for improving the strength, such as metal materials, ceramic materials and the like.

In the oil-water separation device, the material uniform distributor I and the material uniform distributor II are various designs capable of realizing uniform redistribution of materials in the prior art, and have important functions, because good initial distribution of the materials can enable the flow capacity and the retention time of the coalescent filler on the whole section to be approximately equal, and meanwhile, the flow state of the materials in the coalescent dehydration process is continuously stable and uniform. As a specific implementation mode, the material distributor I and the material distributor II are preferably formed by arranging and stacking 5-10 layers of perforated plate liquid distribution plates in a staggered mode, as a more specific implementation mode, aiming at the performance of oil products to be separated, the hole diameter of a perforated plate on the perforated plate liquid distribution plate is 4-8 mm, and the hole center distance is 20-30 mm.

In the oil-water separation device, the upper coalescence demulsification filler layer and the lower coalescence demulsification filler layer are formed by stacking fiber layers with compact concave-convex structures, which are formed by mixing and weaving oleophylic hydrophobic materials and hydrophilic oleophobic materials; preferably woven into any one of X type, V type, 8 type, omega type, drop shape or rhombus type.

In the oil-water separation device, the upper coalescence depth demulsification filler layer comprises a plurality of hollow filter elements, the surface material of each hollow filter element is a fiber layer which is woven by a light-philic phase material and has a compact concave-convex structure, and the surface of each hollow filter element has a compact pore structure, preferably a honeycomb hexagonal pore shape.

In the oil-water separation device, the rapid separation layer is a filler layer which can increase the settling velocity of oil and water and is used for separating oil and water with different densities, and is preferably formed by stacking and arranging a plurality of layers of corrugated porous plates. The corrugated porous plates can be arranged horizontally or obliquely relative to the flowing direction of the liquid.

The liquid to be separated and refined passes through the oil-water separation device and is firstly treated by a pre-separation area, water drops or oil drops with the diameter of more than or equal to 25 mu m in the liquid to be separated are separated and converged, and enter a stable flow area, and a heavy phase and a light phase are layered. Based on the density difference principle, under the action of buoyancy, a light phase enters an upper coalescence demulsification filler layer of an upper coalescence-separation zone, due to the special concave-convex structure on the surface of the fiber and the hydrophilic and oleophilic properties of the material, the entrained heavy phase and a convex structure on the surface of a fiber woven layer are subjected to intensive collision to realize demulsification and coalescence, smaller liquid drops are gradually gathered into larger liquid drops and flow back to a steady flow zone under the action of gravity, and 5-25 mu m liquid drops in the light phase can be removed in the process; the separated light phase continuously enters an upper coalescence depth demulsification filler layer, under the action of a compact structure of the light phase filter element, liquid drops with the diameter less than or equal to 5 mu m are demulsified and separated, and the refined light phase is collected through an upper coalescence outlet. The heavy phase in the steady flow area enters a lower coalescence-separation area, firstly, a small amount of light phase carried in the heavy phase is demulsified and coalesced under the action of a lower coalescence-demulsification filler layer, the separated heavy phase enters a rapid separation layer, and the heavy phase flows downwards more rapidly under the action of a porous corrugated plate and is layered with the small amount of doped light phase, and the heavy phase is discharged through a lower coalescence-outlet.

In the oil-water separation device, the total retention time is set to be 0.5-6 minutes, preferably 1.0-3.0 minutes, and the dehydration rate of the oil product is more than or equal to 97% in the total retention time, so that the retention time is further prolonged, and the volume of equipment is increased, so that the dehydration rate of the oil product is further improved.

The oil-water separation device is provided with a primary separation area, an upper coalescence-separation area and a lower coalescence-separation area respectively by analyzing the existence state and the separation requirement of water in the fed oil product, and realizes the separation of free water drops or oil drops with the diameter of more than or equal to 25 mu m in the liquid to be separated, the demulsification and coalescence of a small amount of heavy phase carried in the light phase, the fine separation of the light phase, the demulsification and coalescence of a small amount of light phase carried in the heavy phase and the fine separation of the heavy phase respectively. The coalescence dewatering or oil removing device has the advantages of short material retention time, high dewatering efficiency and small equipment volume, can realize the deep removal of water, especially emulsified water, in oil products and the removal of emulsified oil drops in sewage, and the removal rate of water or oil is more than or equal to 99 percent.

Drawings

FIG. 1 is a schematic view of the oil-water separation apparatus in example 1.

Wherein: 100. the device comprises a pre-separation area, 101, a feed pipe, 102, a hollow filter element, 103, a stable flow area, 104, a feed inlet, 200, an upper coalescence separation area, 201, a material uniform distributor I, 202, an upper coalescence demulsification filler layer, 203, an upper coalescence depth demulsification filler layer, 204, a light phase discharge port, 300, a lower coalescence separation area, 301, a material uniform distributor II, 302, a lower coalescence demulsification filler layer, 303, a quick separation layer and 304, a heavy phase discharge port.

Detailed Description

The structure and function of the invention are further explained in the following with the attached drawings. The heavy dirty oil properties are shown in table 1. When the first-stage flash tower is adopted in the examples and the comparative examples, the height of the flash tower is 16m, and the diameter of the flash tower is 1.2 m; when 3-stage flash evaporation is adopted in the experiment, the height of the first-stage flash evaporation tower is 15m, the diameter of the top tower is 1.6m, the diameter of the bottom tower is 1.0m, the height of the second-stage flash evaporation tower is 13m, the diameter of the top tower is 1.4m, the diameter of the bottom tower is 1.0m, the height of the third-stage flash evaporation tower is 11m, the diameter of the top tower is 1.2m, and the diameter of the bottom tower is 0.8 m.

A device for separating oil from water, as shown in FIG. 1, comprises a pre-separation zone 100, an upper coalescing-separation zone 200 and a lower coalescing-separation zone 300; the pre-separation area 100 comprises a feed pipe 101, a hollow filter element 102 and a flow stabilizing area 103, wherein the hollow filter element 102 is arranged in the middle of the feed pipe 101, and a feed inlet 104 of the feed pipe 101 is communicated with the center of the hollow filter element 102; the surface material of the hollow filter element 102 is polyester fiber material (oleophylic and hydrophobic), and the hollow filter element 102 is communicated with the feeding pipe 101 to form a stable flow area 103; the upper part of the steady flow area 103 is connected with an upper coalescence-separation area 200, and the upper coalescence-separation area 200 sequentially comprises a material uniform distributor I201, an upper coalescence demulsification filler layer 202 and an upper coalescence depth demulsification filler layer 203 from bottom to top; the lower part of the steady flow area 103 is connected with a lower coalescence-separation area 300, the lower coalescence-separation area 300 sequentially comprises a material uniform distributor II 301, a lower coalescence-demulsification filler layer 302 and a quick separation layer 303 from top to bottom, the upper end of the upper coalescence-separation area 200 is provided with a light phase discharge port 204, and the lower end of the lower coalescence-separation area is provided with a heavy phase discharge port 304.

Table 1 properties of heavy dirty oils.

Example 1

And (3) feeding the heavy dirty oil into a flash tower by adopting primary flash evaporation, wherein the height of a feed inlet is 1/2 of the height of the flash tower, the height-diameter ratio of the flash tower is 40/3, the flash evaporation conditions are 0.45MPa (G) and 155-185 ℃, and after flash evaporation and dehydration are finished, the dehydrated heavy dirty oil is obtained, wherein the content of the heavy dirty oil is 10% m.

Example 2

And (3) feeding the heavy dirty oil into a flash tower by adopting primary flash evaporation, wherein the height of a feeding hole is 5/16 (middle upper part feeding) of the height of the flash tower, the flash evaporation condition is 0.45MPa (G) and 155-185 ℃, and after the flash evaporation and dehydration are finished, the dehydrated heavy dirty oil is obtained, wherein the content of the heavy dirty oil is 8% m.

Example 3

Feeding heavy dirty oil into a first-stage flash tower by adopting three-stage flash evaporation, wherein the height of a feeding hole is 5/16 (middle upper part feeding) of the height of the first-stage flash tower, and the flash evaporation conditions are 0.45MPa (G) and 160 ℃; the heavy dirty oil at the bottom of the tower obtained by the first-stage flash evaporation is subjected to heat exchange and then is sent to a second-stage flash evaporation tank, the height of a feed inlet is 5/16 (feeding at the middle upper part) of the height of the second-stage flash evaporation tower, and the flash evaporation condition is 0.43 MPa (G) and 170 ℃; and the heavy dirty oil at the bottom of the tower obtained by the second-stage flash evaporation is subjected to heat exchange and then is sent to a third-stage flash evaporation tank, the height of a feed inlet is 5/16 (feeding from the middle upper part) of the height of the third-stage flash evaporation tower, the flash evaporation condition is 0.41MPa (G), and the temperature is 180 ℃. And after the three-stage flash evaporation dehydration is finished, the water content in the obtained dehydrated heavy dirty oil is 3%.

Example 4

The structure of the oil-water separation device is as follows: material equipartition ware I201 and material equipartition ware II 301 are formed for piling up by 8 layers of orifice plate cloth liquid board staggered arrangement, and the orifice plate aperture on the orifice plate cloth liquid board is 6mm, and hole centre-to-centre spacing is 24 mm. The upper coalescence demulsification packing layer 202 is formed by stacking 8-type fiber layers with compact concave-convex structures formed by mixing and weaving polyester fibers (oleophylic and hydrophobic) and polypropylene fibers (hydrophilic and oleophobic), and the lower coalescence demulsification packing layer 302 is formed by stacking X-type fiber layers with compact concave-convex structures formed by mixing and weaving polyester fibers (oleophylic and hydrophobic) and polypropylene fibers (hydrophilic and oleophobic); the upper coalescence depth demulsification filler layer 203 comprises a plurality of hollow filter elements, the surfaces of the hollow filter elements are fiber layers which are woven by polyester fiber materials (oleophylic and hydrophobic) and have compact concave-convex structures, and the surfaces of the filter elements are in honeycomb hexagonal hole shapes; the rapid separation layer 303 is formed by horizontally arranging a plurality of layers of corrugated porous plates.

The heavy dirty oil obtained in the embodiment 3 is deeply dehydrated by an oil-water separation device, an oil product to be separated enters the middle of a hollow filter element 103 from a feed inlet 104, water drops larger than or equal to 25 microns in the oil product are intercepted in the middle of the filter element under the oleophylic and hydrophobic action of a shell of the filter element, the separated oil product and water enter a stable flow area 103, the oil product of a light phase is on the upper part, the separated water drops serving as a heavy phase are gathered at the lower layer, the light phase flows upwards to a coalescence and separation area 200 under the pushing of water inlet pressure, enters an upper coalescence demulsification filler layer 202 through a material uniform distributor I201, a small amount of water phase (5 to 25 microns) carried in the light phase oil product is demulsified and coalesced and grown under the action of a concave-convex structure and hydrophilic and oleophylic fibers on the surface of the upper coalescence demulsification filler layer 202, flows back to the stable flow area under the, under the action of oleophylic and hydrophobic properties and a compact surface structure of the filter element, droplets less than or equal to 5 microns in the oil product are demulsified, coalesced and separated, and the refined light-phase oil product is collected by a light-phase discharge port 204; the heavy phase in the steady flow area 103 enters the lower coalescence-separation area 300 downwards, enters the lower coalescence-demulsification filler layer 302 through the material uniform distributor II 301, is demulsified, coalesced and grown up and floats on the upper layer under the action of the concave-convex structure on the surface and the hydrophilic and oleophylic fibers, and enters the rapid separation layer 303, and the water phase flows downwards more rapidly under the action of the corrugated porous plate and is discharged from the heavy phase discharge port 304, wherein the water content is 90-110 mu g/g.

Comparative example 1

And (3) feeding the heavy dirty oil into a flash tower by adopting primary flash evaporation, wherein the feeding hole is positioned at the top of the flash tower, the flash evaporation condition is 0.45MPa (G), the flash evaporation temperature is 155-185 ℃, and after the flash evaporation and dehydration are finished, the dehydrated heavy dirty oil is obtained, wherein the content of the heavy dirty oil is 56% m.

Comparative example 2

And (3) feeding the heavy dirty oil into a flash tower by adopting primary flash evaporation, wherein the height of a feed inlet is 1/16 (top cold reflux inlet feeding) of the height of the flash tower, the flash evaporation condition is 0.45MPa (G) and 155-185 ℃, and after flash evaporation and dehydration are finished, the dehydrated heavy dirty oil is obtained, wherein the content of the heavy dirty oil is 42% m.

Comparative example 3

Conventional electrocoagulators: in the electric dehydrator, the feed is discharged from a distribution pipe arranged below the electrodes and above the oil-water interface, and a step-up transformer arranged on the electric dehydrator ensures that a high-voltage electric field is kept between the electrodes. Under the action of voltage, most charged water drops move to an electrode with opposite charges to the water drops in the original medium, namely, the water drops with positive charges move to a negative electrode, the water drops with negative charges move to a positive electrode, so that an electrophoresis coalescence phenomenon is formed, the adjacent water drops break and coalesce into large water drops, the large water drops coalesce with the surrounding water drops, and therefore the large water drops grow continuously, and the large water drops begin to settle when growing to a certain degree under the action of gravity, so that the oil-water separation process is realized.

The heavy dirty oil obtained in the embodiment 3 is dehydrated by adopting the conventional electric coalescer in an AC/DC power plant with the operating temperature of 40-60 ℃ and the pressure of 0.5-1.0 MPa, and the final water content of the heavy dirty oil is 325-400 mu g/g.

Claims

1. The heavy dirty oil dehydration method is characterized by comprising the following steps: feeding the heavy dirty oil into a flash tower for flash evaporation dehydration treatment, obtaining sewage containing light oil at the tower top, and obtaining dehydrated heavy dirty oil at the tower bottom; the pressure of the flash evaporation dehydration treatment is 0.40-0.65 MPaG, and the temperature of the flash evaporation dehydration treatment in the flash evaporation tower is 155-200 ℃; the heavy dirty oil obtained after dehydration at the tower bottom enters an oil-water separation device for deep dehydration; the device comprises a pre-separation zone, an upper coalescence-separation zone and a lower coalescence-separation zone; the pre-separation area comprises a feeding pipe, a hollow filter element and a stable flow area, the hollow filter element is arranged in the middle of the feeding pipe, and a feeding hole of the feeding pipe is communicated with the center of the hollow filter element or communicated with a space between the hollow filter element and the wall of the feeding pipe; the surface material of the hollow filter element is oleophylic hydrophobic material or hydrophilic oleophobic material, and the hollow filter element is communicated with the stable flow area; the upper part of the steady flow zone is connected with the upper coalescence-separation zone, and the upper coalescence-separation zone sequentially comprises a material uniform distributor I, an upper coalescence demulsification filler layer and an upper coalescence depth demulsification filler layer from bottom to top; the lower part of the steady flow area is connected with the lower coalescence-separation area, the lower coalescence-separation area sequentially comprises a material uniform distributor II, a lower coalescence-demulsification packing layer and a quick separation layer from top to bottom, and two ends of the upper coalescence-separation area and the lower coalescence-separation area are respectively provided with an outlet.

2. The method of claim 1, wherein: the flash evaporation dehydration treatment process is set to be 1-5 levels; and (3) after the heavy dirty oil is subjected to first-stage flash evaporation dehydration, the obtained dehydrated dirty oil enters the next-stage flash evaporation dehydration.

3. The method of claim 1, wherein: the heavy dirty oil is from tank bottom oil sludge generated in a tank cleaning process of an oil refinery, high-water-content dirty oil generated in an electric desalting and water cutting process of an atmospheric distillation device and dirty oil recovered from a sewage treatment plant, and the heavy dirty oil has the water content of 30-85 wt% and the salt content of 1000-3000 mg/L.

4. The method of claim 1, wherein: the feed inlet of the flash tower is located at 1/2-1/3 of the height of the flash tower in terms of height.

5. The method of claim 1, wherein: the height-diameter ratio of the flash tower is 80/5-80/8.

6. The method of claim 1, wherein: the 3-stage flash dehydration was carried out as follows: heating heavy dirty oil to a certain temperature, sending the heated heavy dirty oil into a first-stage flash tower, heating water-containing dirty oil at the bottom of the first-stage flash tower to a certain temperature, sending the heated water-containing dirty oil to a second-stage flash tower, heating water-containing dirty oil at the bottom of the second-stage flash tower to a certain temperature, sending the heated water-containing dirty oil to a third-stage flash tower, obtaining dehydrated heavy dirty oil at the bottom of the third-stage flash tower, cooling light oil-containing sewage at the tops of the first, second and third-stage flash towers, and sending the cooled light oil-containing sewage to a buffer tank; the flash evaporation dehydration treatment temperature of the flash evaporation tower is as follows: the first stage is 155-165 ℃; the second stage is 165-175 ℃; the third stage is 175-185 ℃.

7. An oil-water separation device, which is characterized in that: the device comprises a pre-separation zone, an upper coalescence-separation zone and a lower coalescence-separation zone; the pre-separation area comprises a feeding pipe, a hollow filter element and a stable flow area, the hollow filter element is arranged in the middle of the feeding pipe, and a feeding hole of the feeding pipe is communicated with the center of the hollow filter element or communicated with a space between the hollow filter element and the wall of the feeding pipe; the surface material of the hollow filter element is oleophylic hydrophobic material or hydrophilic oleophobic material, and the hollow filter element is communicated with the stable flow area; the upper part of the steady flow zone is connected with the upper coalescence-separation zone, and the upper coalescence-separation zone sequentially comprises a material uniform distributor I, an upper coalescence demulsification filler layer and an upper coalescence depth demulsification filler layer from bottom to top; the lower part of the steady flow area is connected with the lower coalescence-separation area, the lower coalescence-separation area sequentially comprises a material uniform distributor II, a lower coalescence-demulsification packing layer and a quick separation layer from top to bottom, and two ends of the upper coalescence-separation area and the lower coalescence-separation area are respectively provided with an outlet.

8. The oil-water separator according to claim 7, wherein: the feed pipe is of a horizontal tubular structure.

9. The oil-water separator according to claim 7, wherein: the oleophylic and hydrophobic material is selected from at least one of polyester, polyethylene, polypropylene, polyvinyl chloride, polytetrafluoroethylene, acrylic acid and nylon, or is selected from a material with the surface subjected to oleophylic and hydrophobic treatment.

10. The oil-water separator according to claim 7, wherein: the hydrophilic oleophobic material is selected from natural high molecular polymers with main chains or side chains carrying carboxyl, amino or hydroxyl, or is selected from materials with surfaces subjected to hydrophilic oleophobic treatment.

11. The oil-water separator according to claim 7, wherein: the material uniform distributor I and the material uniform distributor II are formed by arranging and stacking 5-10 layers of perforated plate liquid distribution plates in a staggered mode.

12. The oil-water separator according to claim 11, wherein: the aperture of the pore plate on the pore plate liquid distribution plate is 4-8 mm, and the center distance of the pores is 20-30 mm.

13. The oil-water separator according to claim 7, wherein: the upper coalescence demulsification filler layer and the lower coalescence demulsification filler layer are formed by stacking fiber layers which are formed by mixing and weaving oleophylic hydrophobic materials and hydrophilic oleophobic materials and have compact concave-convex structures.

14. The oil-water separator according to claim 13, wherein the upper and lower coalescence demulsification filler layers are any one of X-shaped, V-shaped, 8-shaped, omega-shaped, drop-shaped, or rhombus-shaped.

15. The oil-water separation device as claimed in claim 7, wherein the upper coalescence depth demulsification filler layer comprises a plurality of hollow filter elements, and the surfaces of the hollow filter elements are fiber layers with dense concave-convex structures woven by light-philic phase materials.

16. The apparatus as claimed in claim 7, wherein the flash separation layer is formed by stacking a plurality of corrugated porous plates, and the corrugated porous plates are arranged horizontally or obliquely with respect to the flow direction of the liquid.