Multistage oil-water separation device based on porous medium and oil-water separation method

Abstract

This invention discloses a multi-stage oil-water separation device and method based on porous media. The device comprises a cover plate, separation chips, a flow guide plate, and porous media installed between the separation chips. This method utilizes the hydrophilicity / hydrophobicity and dimensional structure of the porous media to achieve selective separation of oil and water components. The design of the flow guide channels on the flow guide plate enables multi-stage connection of the oil-water separation device, increasing the separation load and allowing for scale-up of the device, achieving highly efficient oil-water separation. During continuous separation, the oil and water phases can be rapidly and efficiently separated within the device, achieving 100% separation selectivity even at high feed rates. The separation process is more easily controlled, effectively improving the separation efficiency of the oil-water system. This invention enables enhanced oil-water two-phase separation processes and equipment miniaturization in the field of chemical separation technology, significantly improving the system's separation efficiency.

Description

Technical Field

[0001] This invention belongs to the field of chemical separation technology, specifically relating to a multi-stage oil-water separation device and method based on porous media. Background Technology

[0002] With the improvement of living standards and the acceleration of industrialization, the large-scale discharge of oily wastewater poses a significant threat to human living environment and natural ecological security. Oily wastewater comes from a wide range of sources, including domestic wastewater, oil extraction and industrial oily wastewater, solid fuel processing, textile industry wastewater, light industrial leather tanning wastewater, railway and transportation industries, food processing, and machinery industries. Oil-water separation devices can separate the oil and water phases in oily wastewater, thereby reducing the harm of wastewater to the ecological environment. Existing technologies for treating oily wastewater generally suffer from drawbacks such as complex equipment structure, cumbersome process flow, high operating costs, and low treatment efficiency. Furthermore, oil-water separation is not thorough enough, easily causing secondary pollution. Therefore, there is an urgent need to provide an oil-water separation device and method with high separation efficiency, wide applicability, and low cost for treating oily wastewater, solving the oil pollution problem in various oily wastewater systems. Summary of the Invention

[0003] To address the above shortcomings, the present invention aims to provide a multi-stage oil-water separation device and method based on porous media. This method utilizes the design of flow channels on a guide plate to achieve multi-stage separation, increasing the separation load and enabling scale-up of the device. It leverages the surface hydrophilicity / hydrophobicity and dimensional structure of the porous media to achieve selective separation of oil and water components. The separation chip effectively increases the contact area between the oil and water components and the porous media, achieving highly efficient oil-water separation. During continuous separation, the oil and water phases can be rapidly and efficiently separated within the device, achieving 100% separation selectivity even at high feed rates. The separation process is more controllable, effectively improving the separation efficiency of the oil-water system. This method enables enhanced oil-water two-phase separation and equipment miniaturization in the field of chemical separation technology, significantly improving the system's separation efficiency.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A multi-stage oil-water separation device based on porous media includes an upper cover plate, separation chips, a flow guide plate, a lower cover plate, and porous media installed between the separation chips. The separation chips can achieve cyclic superposition of separation components through the flow channels on the flow guide plate to form a multi-stage separation device, thereby improving the separation load and efficiency. The upper cover plate has an inlet hole for the oil-water raw material mixture and an outlet hole for the water phase (oil phase) after oil-water two-phase separation on its front side. The flow guide plate has through holes that communicate with the inlet hole for the oil-water raw material mixture and the outlet hole for the water phase (oil phase) after oil-water two-phase separation on the upper cover plate. The separation chips have through holes that communicate with the inlet hole for the oil-water raw material mixture and the outlet hole for the water phase (oil phase) after oil-water two-phase separation in the flow guide channel of the flow guide plate, as well as through holes that communicate with the flow guide channel of the lower cover plate.

[0006] In the multi-stage oil-water separation device based on porous media provided by the present invention, a flow guide plate is provided with a flow guide channel, which is connected to the separation chip.

[0007] The upper cover plate is provided with an inlet hole for the oil-water raw material mixture and an outlet hole for the water phase (oil phase) after oil-water two-phase separation. The inlet hole and the outlet hole are connected to the flow channel on the guide plate. The separation chip is provided with a corresponding inlet hole for the oil-water raw material mixture and an outlet hole for the oil phase (water phase) after oil-water two-phase separation. The inlet hole and the outlet hole are corresponding to the flow channel. The lower cover plate is provided with an outlet hole for the oil phase (water phase) after oil-water two-phase separation corresponding to the separation chip and an outlet hole corresponding to the flow channel.

[0008] The porous medium has a hydrophobic surface with a pure water contact angle of 125~155°, a thickness of 100~500 μm, an average pore size of 0.05~0.8 μm, and a porous structure of any one of finger-like pores, sponge-like pores, double continuous pores, double spiral pores, vertical pores, and parallel pores. The material is any one of fluoropolymers, polyolefins, and silicon carbide.

[0009] The porous medium has a hydrophilic surface with a pure water contact angle of 10~40°, a thickness of 100~500 μm, an average pore size of 0.05~0.8 μm, and a porous structure of any one of finger-like pores, sponge-like pores, double continuous pores, double spiral pores, vertical pores, and parallel pores. The material is any one of polysulfone, polyethersulfone, cellulose and its derivatives, alumina, zirconium oxide, and titanium oxide.

[0010] The separation process of the multi-stage oil-water separator based on porous media provided by this invention is as follows: The oil-water raw material mixture enters the guide plate through the inlet hole of the upper cover plate, and is divided into two raw material liquids (raw material liquid-1 and raw material liquid-2) by the guide plate. Raw material liquid-1 enters through the inlet hole on the separation chip and the inlet hole of the guide plate. The separated oil phase (water phase) flows out of the multi-stage oil-water separator through the porous media, the outlet hole of the separation chip, the outlet hole of the guide plate, and the outlet hole of the lower cover plate; the separated water phase (oil phase) flows out of the multi-stage oil-water separator through the outlet hole of the separation chip, the outlet hole of the guide plate, and the outlet hole of the upper cover plate. Raw material liquid-2 enters through the inlet hole on the separation chip. The separated oil phase (water phase) flows out of the multi-stage oil-water separator through the porous media, the outlet hole of the separation chip, the outlet hole of the guide plate, and the outlet hole of the lower cover plate; the separated water phase (oil phase) flows out of the multi-stage oil-water separator through the outlet hole of the separation chip, the outlet hole of the guide plate, and the outlet hole of the upper cover plate.

[0011] The oil-water mixture is an oil-in-water emulsion, an oil-in-water emulsion, or an oil-water stratified state, containing an oil phase and an aqueous phase. The oil phase is at least one of kerosene, diesel, gasoline, long-chain alkanes such as hexane, dodecane, tetradecane, hexadecane, and octadecane, benzene, toluene, xylene, mixed benzene, carbon tetrachloride, dichloromethane, chloroform, dioxane, and acetone. The aqueous phase is at least one of water or aqueous solutions of polyvinyl alcohol, gelatin, polyethylene glycol, acetic acid, hydrochloric acid, nitric acid, and sodium hydroxide.

[0012] The feed rate of the oil-water mixture is 0~1000 ml / min, and the separation device has a 100% selectivity for separating the oil-water mixture.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0014] This invention provides a multi-stage oil-water separation device and method based on porous media. The device is simple in structure, easy to scale up, and highly efficient. The method utilizes the design of flow channels on a guide plate to achieve multi-stage separation, increasing the separation load and enabling scale-up. It leverages the surface hydrophilicity / hydrophobicity and dimensional structure of the porous media to achieve selective separation of oil and water components. The separation chip effectively increases the contact area between the oil and water components and the porous media, achieving highly efficient oil-water separation. During continuous separation, the oil and water phases can be rapidly and efficiently separated within the device, achieving 100% separation selectivity even at high feed rates. The separation process is more controllable, effectively improving the separation efficiency of the oil-water system. This invention enables enhanced oil-water two-phase separation and equipment miniaturization in the field of chemical separation technology, significantly improving system separation efficiency and achieving deep treatment of oily wastewater. Attached Figure Description

[0015] Figure 1This is a schematic diagram of the upper cover plate structure of a multi-stage oil-water separation device based on porous media;

[0016] Figure 2 This is a schematic diagram of the separation chip structure of a multi-stage oil-water separation device based on porous media;

[0017] Figure 3 This is a schematic diagram of the guide plate structure of a multi-stage oil-water separation device based on porous media;

[0018] Figure 4 This is a schematic diagram of the lower cover plate structure of a multi-stage oil-water separator based on porous media;

[0019] Figure 5 This is a schematic diagram of a multi-stage oil-water separation device based on porous media.

[0020] Figure 6 This is a diagram of the porous media structure used in Example 1 and Comparative Example 1;

[0021] Figure 7 This is a diagram of the porous media structure used in Example 2;

[0022] Figure 8 This is a diagram of the porous medium structure used in Example 3;

[0023] Figure 9 This is a schematic diagram of the single-stage oil-water separation device based on porous media in Comparative Example 1.

[0024] Figure 10 This is a schematic diagram of the multi-stage oil-water separation device in Comparative Example 2. Implementation

[0025] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the preferred embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0026] This invention relates to a multi-stage oil-water separation device based on porous media. The concept involves designing flow channels on a guide plate to achieve multi-stage separation, increasing the separation load and enabling scalability. The selective separation of oil and water components is achieved by utilizing the surface hydrophilicity / hydrophobicity and dimensional structure of the porous media. A separation chip effectively increases the contact area between the oil and water components and the porous media, achieving highly efficient oil-water separation. Ultimately, this invention enhances the oil-water two-phase separation process and miniaturizes the equipment in the field of chemical separation technology, significantly improving the system's oil-water separation efficiency.

[0027] 1. Figure 5 The diagram shown is an example of a multi-stage oil-water separator based on porous media. This oil-water separator includes an upper cover plate (…). Figure 1 ), separate chip ( Figure 2 ), deflector plate ( Figure 3 ), lower cover plate ( Figure 4 It consists of a porous medium sealed between the discrete chips.

[0028] 2. In the multi-stage oil-water separation device based on porous media provided by the present invention, the front side of the upper cover plate is provided with an inlet hole for the oil-water raw material mixture and an outlet hole for the water phase (oil phase) after oil-water two-phase separation. Figure 1 ).

[0029] 3. In the multi-stage oil-water separation device based on porous media provided by the present invention, the separation chip is provided with an inlet hole for the corresponding oil-water raw material mixture and an outlet hole for the oil phase (water phase) after oil-water separation. The inlet hole and outlet hole correspond to the flow channel. Figure 2 ).

[0030] 4. In the multi-stage oil-water separation device based on porous media provided by the present invention, a flow guide plate is provided with a flow guide channel, which is connected to the separation chip. The flow guide plate is provided with a through hole that is connected to the inlet hole of the oil-water raw material mixture and the outlet hole of the water phase (oil phase) after oil-water separation provided on the upper cover plate. Figure 3 ).

[0031] 5. In the multi-stage oil-water separation device based on porous media provided by the present invention, the lower cover plate is provided with an oil phase (water phase) outlet hole corresponding to the oil-water two-phase separation on the separation chip, and an outlet hole corresponding to the flow channel. Figure 4 ).

[0032] 6. In the multi-stage oil-water separation device based on porous media provided by the present invention, the porous media surface is hydrophobic, the surface pure water contact angle is 125~155°, the thickness is 100~500 μm, the average pore diameter is 0.05~0.8 μm, the porous structure is any one of finger pores, sponge pores, double continuous pores, double spiral pores, vertical pores, and parallel pores, and the material is any one of fluoropolymers, polyolefins, and silicon carbide.

[0033] 10. In the multi-stage oil-water separation device based on porous media provided by the present invention, the porous media surface is hydrophilic, the surface pure water contact angle is 10~40°, the thickness is 100~500 μm, the average pore diameter is 0.05~0.8 μm, the porous structure is any one of finger pores, sponge pores, double continuous pores, double spiral pores, vertical pores, and parallel pores, and the material is any one of polysulfone, polyethersulfone, cellulose and its derivatives, alumina, zirconium oxide, and titanium oxide.

[0034] 11. Figure 5This is a common overall and internal structure pattern for multi-stage oil-water separation devices and for carrying the feed mixture inlet and outlet in this invention. However, in specific implementations, it is not limited to this pattern and can be used in various ways. Figure 5 Further optimizations and improvements are made based on the basic structure.

[0035] 12. Figure 2 This is a common pattern for the overall and internal structure of the separation chip used to separate oil and water phases in this invention. However, in specific implementations, it is not limited to this pattern and can be used in various ways. Figure 2 Further optimizations and improvements will be made based on the basic structure. Example

[0036] The porous medium is made of hydrophobic polyvinylidene fluoride (PVDF), with a pure water contact angle of 140°, a thickness of 200 μm, an average pore size of 0.22 μm, and a sponge-like pore structure. The separation system is an octadecane / water mixture in an oil-water stratified state. The octadecane / water mixture enters the guide plate through the inlet hole of the upper cover plate at a feed rate of 500 ml / min. The guide plate then divides the mixture into two streams (octadecane / water mixture-1 and octadecane / water mixture-2). Octadecane / water mixture-1 enters through the inlet holes on the separation chip and the guide plate. The separated octadecane flows out of the multi-stage oil-water separator through the porous medium, the outlet hole of the separation chip, the outlet hole of the guide plate, and the outlet hole of the lower cover plate. The separated water flows out of the multi-stage oil-water separator through the outlet holes of the separation chip, the outlet hole of the guide plate, and the outlet hole of the upper cover plate. The octadecane / water mixture-2 enters through the inlet port on the separator chip. The separated octadecane flows out of the multi-stage oil-water separator through the porous medium, the outlet port of the separator chip, the outlet port of the guide plate, and the outlet port of the lower cover plate. The separated water flows out of the multi-stage oil-water separator through the outlet ports of the separator chip, the outlet port of the guide plate, and the outlet port of the upper cover plate. After separation by the multi-stage oil-water separator, the separation selectivity is 100%. Example

[0037] The porous medium is made of hydrophilic polyethersulfone, with a pure water contact angle of 30°, a film thickness of 200 μm, an average pore size of 0.22 μm, and a sponge-like pore structure. The separation system is a xylene / polyethylene glycol mixture in an emulsion state. The xylene / polyethylene glycol mixture enters the guide plate through the inlet hole of the upper cover plate at a feed rate of 800 ml / min. The guide plate then divides the mixture into two feed streams (xylene / polyethylene glycol mixture-1 and xylene / polyethylene glycol mixture-2). Xylene / polyethylene glycol mixture-1 enters through the inlet holes on the separation chip and the guide plate. The separated polyethylene glycol flows out of the multi-stage oil-water separator through the porous medium, the outlet hole of the separation chip, the outlet hole of the guide plate, and the outlet hole of the lower cover plate. The separated xylene flows out of the multi-stage oil-water separator through the outlet holes of the separation chip, the outlet hole of the guide plate, and the outlet hole of the upper cover plate. The xylene / polyethylene glycol mixture-2 enters through the inlet port on the separator chip. The separated polyethylene glycol flows out of the multi-stage oil-water separator through the porous medium, the outlet port of the separator chip, the outlet port of the guide plate, and the outlet port of the lower cover plate. Similarly, the separated xylene flows out of the multi-stage oil-water separator through the outlet ports of the separator chip, the outlet port of the guide plate, and the outlet port of the upper cover plate. After separation by the multi-stage oil-water separator, the separation selectivity is 100%. Example

[0038] The porous medium is made of hydrophilic polysulfone, with a pure water contact angle of 20°, a film thickness of 200 μm, an average pore size of 0.45 μm, and a double continuous pore structure. The separation system is a dichloromethane / acetic acid aqueous solution mixture in an oil-water stratified state. The dichloromethane / acetic acid aqueous solution mixture enters the guide plate through the inlet hole of the upper cover plate at a feed rate of 1000 ml / min, and is divided into two feed liquids (dichloromethane / acetic acid aqueous solution mixture-1 and dichloromethane / acetic acid aqueous solution mixture-2) through the guide channel. Dichloromethane / acetic acid aqueous solution mixture-1 enters through the inlet hole on the separation chip and the inlet hole of the guide plate. The separated acetic acid aqueous solution flows out of the multi-stage oil-water separator through the porous medium, the outlet hole of the separation chip, the outlet hole of the guide plate, and the outlet hole of the lower cover plate; the separated dichloromethane flows out of the multi-stage oil-water separator through the outlet hole of the separation chip, the outlet hole of the guide plate, and the outlet hole of the upper cover plate. The dichloromethane / acetic acid aqueous solution mixture-2 enters through the inlet port on the separator chip. The separated acetic acid aqueous solution flows out of the multi-stage oil-water separator through the porous medium, the outlet port of the separator chip, the outlet port of the guide plate, and the outlet port of the lower cover plate. The separated dichloromethane flows out of the multi-stage oil-water separator through the outlet ports of the separator chip, the outlet port of the guide plate, and the outlet port of the upper cover plate. After separation by the multi-stage oil-water separator, the separation selectivity is 100%.

[0039] Comparative Example 1:

[0040] The porous medium is made of hydrophobic polyvinylidene fluoride (PVDF), with a pure water contact angle of 140°, a film thickness of 200 μm, an average pore size of 0.22 μm, and a sponge-like pore structure. The separation system is an octadecane / water mixture in an oil-water stratified state. The octadecane / water mixture enters the single-stage separation unit through the inlet hole of the upper cover plate at a feed rate of 500 ml / min. The separated octadecane flows out of the single-stage oil-water separator through the outlet holes of the porous medium and the lower cover plate; the separated water flows out of the single-stage oil-water separator through the outlet hole of the upper cover plate. After separation by the single-stage oil-water separator, the separation selectivity is 45%.

[0041] Comparative Example 2:

[0042] Oil-water separation is performed using an oil-water separator without porous media. The separation system is an octadecane / water mixture in a stratified state. The octadecane / water mixture enters the guide channel on the reverse side of the upper cover plate through the inlet hole at a feed rate of 500 ml / min, and is divided into two feed streams (octadecane / water mixture-1 and octadecane / water mixture-2) through the guide channel. The octadecane / water mixture also enters the guide plate through the inlet hole at a feed rate of 500 ml / min, and is divided into two feed streams (octadecane / water mixture-1 and octadecane / water mixture-2) through the guide channel of the guide plate. Octadecane / water mixture 1 enters through the inlet holes on the separator chip and the inlet hole on the guide plate. The separated octadecane flows out of the multi-stage oil-water separator through the porous medium, the outlet holes of the separator chip, the outlet holes of the guide plate, and the outlet hole of the lower cover plate. The separated water flows out of the multi-stage oil-water separator through the outlet holes of the separator chip, the outlet holes of the guide plate, and the outlet hole of the upper cover plate. Octadecane / water mixture 2 enters through the inlet hole on the separator chip. The separated octadecane flows out of the multi-stage oil-water separator through the porous medium, the outlet holes of the separator chip, the outlet holes of the guide plate, and the outlet hole of the lower cover plate. The separated water flows out of the multi-stage oil-water separator through the outlet holes of the separator chip, the outlet holes of the guide plate, and the outlet hole of the upper cover plate. After separation by the multi-stage oil-water separator, the separation selectivity is 60%.

[0043] As can be seen from the embodiments and comparative examples, the present invention utilizes the surface hydrophilicity and hydrophobicity and size structure of porous media to achieve selective separation of oil and water components. Through the design of the guide plate and flow channel, the oil-water separation device can be multi-stage, increasing the separation load and enabling the device to be scaled up. The separation chip effectively increases the contact area between the oil and water components and the porous media by guiding the flow of oil and water components. This can achieve process intensification and equipment miniaturization in oil-water separation, greatly improving the oil-water separation efficiency of the system.

[0044] Any aspects not covered in this invention are applicable to existing technologies.

Claims

1. A multi-stage oil-water separation device based on porous media, characterized in that: The oil-water separation device includes an upper cover plate, a separation chip, a flow guide plate, a lower cover plate, and a porous medium installed between the separation chips. The flow guide plate is provided with a flow guide channel, which is connected to the separation chip. The separation chips can be circulated, superimposed, and connected in series through the flow guide channel on the flow guide plate. The upper cover plate has an inlet hole for the oil-water raw material mixture and an outlet hole for the water / oil phase after oil-water two-phase separation on its front side. The guide plate has a through hole that communicates with the inlet hole for the oil-water raw material mixture and the outlet hole for the water / oil phase after oil-water two-phase separation on the upper cover plate. The inlet hole and outlet hole on the upper cover plate are connected to the guide channel on the guide plate. The separation chip has a corresponding inlet hole for the oil-water raw material mixture and an outlet hole for the oil / water phase after oil-water two-phase separation. The inlet hole and outlet hole of the separation chip are connected to the guide channel. The lower cover plate has an outlet hole for the oil / water phase after oil-water two-phase separation corresponding to that on the separation chip. The lower cover plate also has an outlet hole corresponding to the guide channel. The porous medium is hydrophobic or hydrophilic, wherein the hydrophobic porous medium has a pure water contact angle of 125~155°, a thickness of 100~500 μm, an average pore size of 0.05~0.8 μm, and the porous structure is any one of finger pores, sponge pores, double continuous pores, double spiral pores, vertical pores, and parallel pores, and the material is any one of fluoropolymers, polyolefins, and silicon carbide; The hydrophilic porous medium has a pure water contact angle of 10~40°, a thickness of 100~500 μm, an average pore size of 0.05~0.8 μm, and a porous structure of any one of finger pores, sponge pores, double continuous pores, double spiral pores, vertical pores, and parallel pores. The material is any one of polysulfone, polyethersulfone, cellulose and its derivatives, alumina, zirconium oxide, and titanium oxide.

2. An oil-water separation method based on a multi-stage oil-water separation device using porous media, characterized in that, Using the multi-stage oil-water separation device based on porous media as described in claim 1, the specific process of the oil-water separation is as follows: the raw material mixture of oil and water enters the guide channel on the reverse side of the upper cover plate through the inlet hole of the upper cover plate, and is divided into two raw material liquids: raw material liquid-1 and raw material liquid-2 by the guide plate; Raw material liquid-1 enters through the inlet hole on the separator chip and the inlet hole on the guide plate. The separated oil / water phase flows out of the multi-stage oil-water separator through the porous medium, the outlet hole of the separator chip, the outlet hole of the guide plate and the outlet hole of the lower cover plate. The separated water / oil phase flows out of the multi-stage oil-water separator through the outlet hole of the separator chip, the outlet hole of the guide plate and the outlet hole of the upper cover plate. The raw material liquid-2 enters through the inlet hole on the separator chip, and the separated oil / water phase flows out of the multi-stage oil-water separator through the porous medium, the outlet hole of the separator chip, the outlet hole of the guide plate and the outlet hole of the lower cover plate. The separated water / oil phases flow out of the multi-stage oil-water separator through the outlet holes of the separator chip, the outlet holes of the guide plate, and the outlet holes of the top cover plate.

3. The method according to claim 2, characterized in that: The oil-water mixture is an oil-in-water emulsion, an oil-in-water emulsion, or an oil-water stratified state, containing an oil phase and an aqueous phase. The oil phase is at least one of kerosene, diesel, gasoline, n-hexane, dodecane, tetradecane, hexadecane, octadecane long-chain alkanes, benzene, toluene, xylene, mixed benzene, carbon tetrachloride, dichloromethane, chloroform, dioxane, and acetone. The aqueous phase is at least one of water or an aqueous solution of polyvinyl alcohol, gelatin, polyethylene glycol, acetic acid, hydrochloric acid, nitric acid, and sodium hydroxide.

4. The method according to claim 2, characterized in that: The feed rate of the oil-water mixture is 0~1000 ml / min, and the separation device has a 100% selectivity for separating the oil-water mixture.

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