Feed liquid combined purification unit, system and purification and regeneration method

Abstract

The invention discloses a feed liquid combined purification unit, a feed liquid combined purification system and a purification and regeneration method. The combined purification unit is used for pretreatment of oil-containing raw materials and comprises a ceramic membrane base body which is used for oil removal treatment of feed liquid and provided with a plurality of channels vertically extending along the base body, the channels serve as inlet channels for feed liquid purification, and ceramic membranes are sintered on the inner walls of the channels; and the filler layer is adjacent to the ceramic membrane substrate, is combined with the ceramic membrane substrate to form a purification unit, and is used for receiving the deoiled feed liquid and adsorbing harmful substances dissolved in a water phase. According to the invention, the ceramic membrane substrate is used as the wall surface of the filler layer, so that purification processes such as oil removal treatment and removal of harmful substances dissolved in a water phase can be completed in the same unit; the two independent purification units for removing oil through the ceramic membrane and removing harmful substances dissolved in water through the packed bed can be combined into one, continuous feeding and membrane regeneration can be achieved only through one set of membrane filtering unit, and regeneration waste cannot be additionally generated.

Description

Technical Field

[0001] This invention relates to the field of petrochemical oil-containing liquid purification technology, and in particular to a liquid purification unit, system, and purification and regeneration method for raw material pretreatment. Background Technology

[0002] In the petrochemical industry, the purification of oily liquids generally requires oil removal treatment, primarily for raw material pretreatment. Oily materials refer to the oily components in aqueous materials, including mineral oils and biomass oils, and in chemical reaction systems, can refer to hydrocarbons with C9 or higher. Because the oily components in materials can cause blockages in subsequent system pipelines or affect subsequent reactions, they need to be removed. Oils in materials can be classified into suspended oils with a particle size ≥100μm, dispersed oils with a particle size of 10-100μm, and emulsified oils with a particle size of 0.1-10μm. Suspended oils tend to float quickly after settling, forming a continuous oil film on the water surface; dispersed oils remain suspended and diffused in the aqueous system, and with sufficient time to settle or under external force, can coagulate into larger oil droplets that float to the surface, or may further shrink and transform into emulsified oils; emulsified oils are generally stably dispersed in the aqueous system in a water-in-oil form, and oil-water separation is difficult to achieve simply by settling.

[0003] Existing oil-water separation methods employ membrane separation. Membrane separation treats oily liquids or wastewater by using porous membranes as the separation medium. The membranes trap oil and surfactants while allowing water molecules to pass through, thus achieving oil-water separation. The key to membrane separation technology is the selection of the membrane and its components. Membrane materials can be categorized into polymer membranes and inorganic membranes.

[0004] Existing technologies include oil removal techniques using ceramic membranes for oily liquids or wastewater. For example, Chinese patent application CN113060884A discloses a petrochemical oily wastewater and sludge purification and reuse system, comprising a first inlet pipe, a solid-liquid separation device, an oil-water separation device, a membrane separation device, and a drying device. The first inlet pipe is connected to the feed end of the solid-liquid separation device; the liquid phase outlet of the solid-liquid separation device is connected to the feed inlet of the oil-water separation device; its solid phase outlet is connected to the feed inlet of the drying device; the aqueous phase outlet of the oil-water separation device is connected to the feed inlet of the membrane separation device; its oil phase outlet is connected to an oil collection and transportation device; the concentrated liquid output end of the membrane separation device is connected to the oil-water separation device; and its clarified liquid output end is connected to a drainage ditch. This scheme utilizes a system process of horizontal screw centrifuge + disc centrifuge + organic ceramic membrane treatment and solid sludge drying. However, in this type of scheme, the oil removal process and the removal of water-soluble harmful substances from the material are completed in different corresponding treatment units.

[0005] Therefore, there is an urgent need for a combined liquid-material purification unit, system, and purification and regeneration method that can complete the purification process such as oil removal and removal of harmful substances dissolved in the liquid phase in the same unit, thereby effectively saving space and energy consumption.

[0006] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to provide a combined material and liquid purification unit for raw material pretreatment. By using a ceramic membrane substrate as the wall surface of the filler layer, purification processes such as oil removal and removal of harmful substances dissolved in the aqueous phase can be completed in the same unit.

[0008] Another objective of this invention is to provide a combined liquid purification system and purification and regeneration method, which can combine two independent purification units—ceramic membrane degreasing and packed bed removal of water-soluble harmful substances—into one, and can also achieve continuous feeding and membrane regeneration using only one membrane filtration unit without generating additional regeneration waste.

[0009] To achieve the above objectives, according to a first aspect of the present invention, the present invention provides a liquid-feed combination purification unit for pretreatment of oily raw materials, comprising: a ceramic membrane substrate for oil removal treatment of the liquid and having multiple channels extending vertically along the substrate, the channels serving as inlet channels for liquid purification, the inner walls of the channels being sintered with ceramic membranes; and a packing layer disposed adjacent to the ceramic membrane substrate and combined into a purification unit for receiving the oil-removed liquid and adsorbing harmful substances dissolved in the aqueous phase.

[0010] Furthermore, in the above technical solution, the ceramic membrane substrate can be plate-shaped, serving as the partition or wall of the filler layer.

[0011] Furthermore, in the above technical solution, when the ceramic film substrate is plate-shaped and serves as the wall of the filler layer, the number of filler layers can be multiple and arranged laterally, and the top and bottom surfaces of the filler layers can both be V-shaped; correspondingly, multiple ceramic film substrates can be arranged vertically.

[0012] Furthermore, in the above technical solution, when the ceramic film substrate is plate-shaped and serves as the partition wall of the filler layer, the number of filler layers can be multiple and arranged laterally, and the top and bottom surfaces of the filler layers can be inverted V-shaped; correspondingly, one or more ceramic film substrates can be arranged vertically.

[0013] Furthermore, in the above technical solution, the ceramic membrane substrate can also be in the shape of a hollow cylinder and serve as the outer wall of the filler layer, with the hollow part serving as the filler layer; the top and bottom surfaces of the filler layer can both be inverted conical surfaces.

[0014] Furthermore, in the above technical solution, the ceramic membrane substrate can also be tubular and serve as the axis of the filler layer, with the filler layer located around the ceramic membrane substrate; both the top and bottom surfaces of the filler layer can be conical surfaces.

[0015] Furthermore, in the above technical solution, the liquid inlet is located at the bottom of the channel; the liquid outlet may include a first outlet located at the lowest point of the bottom surface of the packing layer and a second outlet located at the top of the channel; the liquid at the first outlet is a purified liquid after degreasing and removing harmful substances dissolved in the aqueous phase, and the liquid at the second outlet is a turbid liquid carrying grease and entering the circulation tank.

[0016] Furthermore, in the above technical solution, when the filler layer is arranged in a V-shape, the angle between the bottom surface of the filler layer and the vertical center line of the filler layer is preferably 30° < α < 60°; the angle between the top surface of the filler layer and the ceramic membrane substrate is preferably 30° < α' < 60°.

[0017] Furthermore, in the above technical solution, when the filler layer is arranged in an inverted V shape, the angle between the bottom surface of the filler layer and the vertical outer edge of the filler layer is preferably 30° < α < 60°; the angle between the top surface of the filler layer and the ceramic membrane substrate is preferably 30° < α' < 60°.

[0018] According to a second aspect of the present invention, the present invention provides a liquid-feed combination purification system, which uses a purification unit as described in any of the foregoing embodiments.

[0019] Furthermore, in the above technical solution, the system may also include: a storage tank, which is connected to the first outlet of the purification unit, for storing the purified liquid after degreasing and removal of harmful substances dissolved in the aqueous phase; and a circulation tank, which is connected to the second outlet of the purification unit, for receiving turbid liquid carrying grease and pumping the liquid to be purified to the liquid inlet of the purification unit.

[0020] Furthermore, in the above technical solution, a portion of the purified liquid in the storage tank can be used in downstream processes, while the other portion can be sent to a circulation tank via a regulating pipeline to adjust the feed concentration. The ratio of the flow rate of the regulating pipeline to the flow rate of the first external feed pipeline is preferably 0 to 0.5.

[0021] Furthermore, in the above technical solution, the storage tank can also be used to introduce the purified liquid from the bottom of the packing layer after the system has been running for a long time, and then backwash the ceramic membrane installed on the inner wall of the channel through the ceramic membrane substrate.

[0022] According to a third aspect of the present invention, the present invention provides a method for purification and regeneration of a feed liquid combination, employing any one of the preceding systems, for pretreatment of oily raw materials without solid particles, comprising the following steps: A. Pumping the feed liquid to be purified into each channel of a ceramic membrane substrate adjacent to the packing layer; B. Under the action of the ceramic membrane, the feed liquid in the channel retains free grease within the channel, while the aqueous phase in the feed liquid permeates through the ceramic membrane substrate to the adjacent packing layer; C. The aqueous phase adsorbs harmful substances dissolved in the aqueous phase through the packing layer, obtaining purified feed liquid at the first outlet and storing it in a storage tank; D. The turbid liquid carrying grease enters a circulation tank through the second outlet for circulation; E. After the system has been running for a long time, the purified feed liquid in the storage tank is introduced from the bottom of the packing layer and then backwashed through the ceramic membrane substrate onto the ceramic membrane disposed on the inner wall of the channel for membrane regeneration treatment.

[0023] Furthermore, in the above technical solution, step E may also include: when the adsorption concentration in the packing layer is too high, introducing a high-concentration cleaning agent into the backwashing pipeline through a second feed pipeline. The high-concentration cleaning agent is preferably ethanol or acetone.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1) This invention can combine different purification units into one independent unit. That is, by combining two independent purification units, ceramic membrane degreasing and packing bed, it can not only complete the purification process such as degreasing and removal of harmful substances dissolved in the aqueous phase in the same unit, but also save costs and space.

[0026] 2) The ceramic membrane substrate of the present invention can be designed in the form of a plate, serving as a partition or wall between adjacent filler layers. It can be degreased in the same unit first, and the degreased liquid can remove harmful substances through the adsorption of the filler. The inner wall of the liquid channel of the ceramic membrane substrate is sintered with a ceramic membrane. By making the ceramic membrane substrate into a plate shape, it can serve as a wall between the filler layers, making the combination of the two possible. At the same time, the plate-shaped structure facilitates the design of channel arrays, resulting in higher degreasing and circulation efficiency.

[0027] 3) The ceramic membrane substrate of the present invention can also be designed as a hollow cylinder and serve as the outer wall of the filler layer. With such a structural design, the direction of the degreased liquid in the filler layer is more concentrated and uniform, and all are radially inward. Compared with the flat ceramic membrane substrate, when using the same volume of filler, the hollow cylindrical ceramic membrane substrate design can make the removal efficiency of harmful substances in the aqueous phase higher.

[0028] 4) The ceramic membrane substrate of the present invention can also be designed as a tube and serve as the axis of the filler layer. The tube-shaped ceramic membrane substrate is placed in the middle and the filler layer is placed on the periphery. With this structural design, not only is the ceramic membrane substrate easier to process and manufacture, but the volume of the filler layer can also be effectively increased. Its outer edge can extend all the way to the inner wall of the shell of the purification unit, which can greatly increase the amount of harmful substances in the water phase that can be treated.

[0029] 5) The liquid-feed combination purification unit of the present invention can be arranged according to different actual working conditions through different ceramic membrane substrate structure designs, and is more adaptable to different liquid composition and downstream process requirements;

[0030] 6) When the packing layer of the present invention is arranged horizontally, the liquid will flow downwards under the action of gravity after entering the packing layer. In order to ensure the full utilization of all parts of the packing layer, the packing layer is designed as a V-shape or inverted V-shape, which can avoid the waste of packing caused by the liquid not being able to flow through some areas of the packing layer.

[0031] 7) The purification system and purification regeneration method of the present invention can regenerate the ceramic membrane during the purification process, and only one membrane filtration unit is needed to achieve continuous feeding. In addition, the clear liquid generated by the purification unit in the system is used to backwash and regenerate the ceramic membrane, which does not require the use of water sources outside the system. Moreover, the regenerated waste liquid can be filtered again after dilution in the next cycle, without generating additional regeneration waste, which is more environmentally friendly.

[0032] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, and to make the above and other objects, technical features and advantages of the present invention easier to understand, one or more preferred embodiments are listed below and described in detail with reference to the accompanying drawings. Attached Figure Description

[0033] Figure 1 This is a connection diagram of the liquid-feed combination purification system of the present invention.

[0034] Figure 2 This is a schematic diagram illustrating the application of Embodiment 1 of the liquid-feed combination purification unit of the present invention.

[0035] Figure 3 This is a schematic diagram illustrating the application of Embodiment 2 of the liquid-feed combination purification unit of the present invention.

[0036] Figure 4 This is a three-dimensional structural schematic diagram of Embodiment 1 of the liquid-feed combination purification unit of the present invention.

[0037] Figure 5 This is a three-dimensional structural schematic diagram of Embodiment 2 of the liquid-feed combination purification unit of the present invention.

[0038] Figure 6 This is a schematic diagram illustrating the application of Embodiment 3 of the liquid-feed combination purification unit of the present invention.

[0039] Figure 7 This is a schematic diagram illustrating the application of Embodiment 4 of the liquid-feed combination purification unit of the present invention.

[0040] Figure 8 This is a schematic diagram illustrating the application of Embodiment 5 of the liquid-feed combination purification unit of the present invention.

[0041] Figure 9 This is a three-dimensional structural schematic diagram of Embodiment 3 of the liquid-feed combination purification unit of the present invention.

[0042] Figure 10 This is a three-dimensional structural schematic diagram of Embodiment 4 of the liquid-feed combination purification unit of the present invention.

[0043] Figure 11 This is a three-dimensional structural schematic diagram of Embodiment 5 of the liquid-feed combination purification unit of the present invention.

[0044] Figure 12 This is a three-dimensional structural schematic diagram of Embodiment 6 of the liquid-feed combination purification unit of the present invention.

[0045] Figure 13 This is a three-dimensional structural schematic diagram of Embodiment 7 of the liquid-feed combination purification unit of the present invention.

[0046] Explanation of key figure labels:

[0047] 1-Combined purification unit, 11-Ceramic membrane substrate, 111-Feed channel, 12-Packaging layer, 2-Storage tank, 21-First discharge pipeline, 3-Circulation tank, 31-First feed pipeline, 32-Second discharge pipeline, 4-Circulation pipeline, 5-Clear liquid pipeline, 6-Regulating pipeline, 7-Pre-membrane pipeline, 8-Backflushing pipeline, 9-Second feed pipeline. Detailed Implementation

[0048] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0049] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0050] In this document, for ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” “above,” “upper,” etc., are used to describe the relationship of one element or feature to another element or feature in the accompanying drawings. It should be understood that spatial relative terms are intended to encompass different orientations of an object in use or operation, in addition to those depicted in the figures. For example, if an object in the figure is flipped, an element described as “below” or “under” another element or feature would be oriented “above” that element or feature. Thus, the exemplary term “below” can encompass both the downward and upward orientations. An object may also have other orientations (rotated 90 degrees or other orientations), and the spatial relative terms used herein should be interpreted accordingly.

[0051] In this document, the terms "first," "second," etc., are used to distinguish two different elements or parts, and are not used to define specific positions or relative relationships. In other words, in some embodiments, the terms "first," "second," etc., can also be used interchangeably.

[0052] This invention addresses the problem in existing technologies where different purification units are required for oil removal and the removal of harmful substances dissolved in the aqueous phase or substances unwanted by downstream processes during the pretreatment of raw material solutions. It proposes a novel technical concept that combines these different purification units into a single, independent unit. Specifically, by integrating two separate purification units—a ceramic membrane for oil removal and a packed bed for removing harmful substances from the aqueous phase—into one unit, the oil removal and removal of harmful substances dissolved in the aqueous phase can be completed within a single unit, saving costs and space. Therefore, this invention provides a combined purification unit 1 for oily raw material pretreatment, comprising at least a ceramic membrane substrate 11 and a packing layer 12. The ceramic membrane substrate 11 is used for oil removal and has multiple channels 111 extending vertically along the substrate. These channels 111 serve as inlet channels for purification, and the inner walls of the channels are sintered with ceramic membranes (not shown in the figure). The packing layer 12 is arranged adjacent to the ceramic membrane substrate 11 and combined to form a purification unit, used to receive the oil-removed liquid and adsorb harmful substances dissolved in the aqueous phase. Figure 1 A schematic diagram of the connection of the liquid-feed combination purification unit 1 of the present invention in the purification system is shown. The ceramic membrane substrate 11 can be made into different shapes and can be combined with the packing layer 12 in different ways to adapt to different working conditions and liquid compositions.

[0053] Example 1

[0054] like Figure 2 , 4As shown, the liquid-feed purification unit 1 in this embodiment uses two plate-shaped ceramic membrane substrates 11 and a packing layer 12 (i.e., a basic unit). Both ceramic membrane substrates 11 are vertically arranged and serve as the walls of the packing layer 12, sandwiching the packing layer in between. The top and bottom surfaces of the packing layer are V-shaped. The liquid to be purified first enters the ceramic membrane substrate 11 (i.e., multiple vertically extending channels 111 within the plate serve as the inlet channels for liquid purification). It undergoes degreasing treatment through the ceramic membrane sintered on the inner wall of the channels 111 (oil cannot pass through the ceramic membrane, but the aqueous phase can). After degreasing, the liquid passes through the ceramic membrane substrate 11 into the packing layer 112 for the removal of harmful substances dissolved in the aqueous phase. This embodiment is suitable for the pretreatment of raw material liquids that do not contain solid particles or have already undergone solid particle removal. If the oil content and the content of harmful substances dissolved in the aqueous phase in the liquid are low, a single basic unit of this embodiment can be used for purification.

[0055] Specifically, further reference Figure 2 and Figure 4 In addition to the ceramic membrane substrate 11 and the packing layer 12, the liquid purification unit 1 of this embodiment is also connected to the storage tank 1 and the circulation tank 2. The liquid to be purified is pumped from the circulation tank 3 to each channel 111 (an array of channels formed by vertically penetrating through holes in the plate-shaped substrate, see reference) of the ceramic membrane substrate 11 of the purification unit 1. Figure 4 The feed liquid undergoes degreasing treatment via a ceramic membrane. The ceramic membrane retains free grease within channel 111, while the aqueous phase permeates through the ceramic membrane substrate 11 to the packing layer 12. The degreased feed liquid then enters the packing layer 12, where the packing layer adsorbs dissolved harmful substances, resulting in purified feed liquid at the lowest point of the V-shaped bottom surface of the packing layer 12. The harmful substances for subsequent processes can be one or more of the following, depending on the process: sulfate, nitrate, bicarbonate, hydrogen silicate, hydroxide, chloride ions, etc.; or one or more of the following, such as iron, aluminum, calcium, magnesium, potassium, sodium, hydrogen ions, etc.; or aromatic substances containing benzene rings, etc. The purified feed liquid enters the storage tank through the clean liquid pipeline 5. Since the degreased liquid enters the packing layer 1 and flows downwards at an angle under gravity, in order to ensure full utilization of all parts of the packing layer 12, the packing layer in this embodiment is designed as a V-shape to avoid the liquid being unable to flow through the packing at the upper middle part of the packing layer, thus avoiding waste of packing. Preferably, but not limitingly, the angle between the bottom surface of the packing layer 12 and the vertical centerline of the packing layer is 30° < α < 60°; the angle between the top surface of the packing layer 12 and the ceramic membrane substrate 11 is 30° < α' < 60°. Since both the upper and lower ends of the channel are open, part of the liquid entering the channel is degreased and enters the packing layer, while the other part flows out of the channel through the inlet and outlet of channel 111. Therefore, this part of the turbid liquid can carry the grease in the ceramic membrane channel and circulate through the circulation pipe 4.

[0056] This embodiment combines a ceramic membrane substrate with a packing layer. The ceramic membrane substrate serves as the wall surface of the packing layer, allowing for pre-degreasing within the same unit. The degreased liquid then removes harmful substances through the adsorption of the packing. The ceramic membrane substrate consists of a ceramic membrane matrix and a ceramic membrane (sintered into the inner wall of the channel of the substrate). By fabricating it into a plate shape, it can serve as the wall surface of the packing layer, making the combination of the two possible. At the same time, the plate-like structure facilitates the design of channel arrays, resulting in higher degreasing and circulation efficiency. The V-shaped packing layer design minimizes packing waste. This embodiment is more suitable for the pretreatment of raw material liquids that do not contain solid particles or have already undergone solid particle removal. A single basic unit can handle conditions with low oil content and low levels of harmful substances dissolved in the aqueous phase.

[0057] Example 2

[0058] like Figure 3 , 5 As shown, the liquid-feed purification unit 1 in this embodiment is formed by arranging each basic unit horizontally based on embodiment 1. The ceramic membrane substrate 11 in this embodiment is still plate-shaped and serves as the wall surface of the filler layer 12. Multiple filler layers 12 are arranged horizontally, similar to embodiment 1, with both the top and bottom surfaces of the filler layer 12 being V-shaped. Correspondingly, multiple ceramic membrane substrates 11 are arranged vertically. This embodiment is also suitable for the pretreatment of raw material liquids that do not contain solid particles or have already undergone solid particle removal, achieving the same technical effects as embodiment 1. Compared to embodiment 1, it is more suitable for conditions with high oil content in the liquid and high content of harmful substances dissolved in the aqueous phase, effectively increasing the liquid-feed processing capacity of the purification unit.

[0059] Example 3

[0060] like Figure 6 , 9As shown, the liquid-feed combination purification unit 1 in this embodiment employs a plate-shaped ceramic membrane substrate 11 and two packing layers 12 (i.e., a basic unit). The ceramic membrane substrate 11 is arranged vertically, and the two packing layers 12 are respectively disposed on both sides of the ceramic membrane substrate 11 (i.e., the ceramic membrane substrate 11 serves as the partition wall of the packing layers 12). The top and bottom surfaces of the entire assembly formed by the two packing layers are both inverted V-shaped. Preferably, but not limitingly, the angle between the bottom surface of the packing layer 12 and the vertical outer edge of the packing layer is 30° < α < 60°; the angle between the top surface of the packing layer 12 and the ceramic membrane substrate is 30° < α' < 60°. Similar to Example 1, in this example, the liquid to be purified first enters the ceramic membrane substrate 11 (i.e., the multiple vertically extending channels 111 within the plate serve as the inlet channels for liquid purification). The liquid undergoes degreasing treatment through the ceramic membrane sintered on the inner wall of the channels 111 (oil cannot pass through the ceramic membrane, but the aqueous phase can). After degreasing, the liquid passes through the ceramic membrane substrate 11 into the filler layer 112 for the removal of harmful substances dissolved in the aqueous phase. When this example is used alone as a basic unit, the filler material filling both sides of the ceramic membrane substrate 11 can extend to the inner wall of the purification unit housing. This is suitable for situations where the oil content of the liquid is low but the content of harmful substances dissolved in the aqueous phase is high. In this case, one basic unit of this example can be used for purification.

[0061] Example 4

[0062] like Figure 7 , 10 As shown, the liquid-feed combination purification unit 1 in this embodiment is formed by arranging each basic unit horizontally based on embodiment 3. The ceramic membrane substrate 11 in this embodiment is still plate-shaped and serves as the partition between the packing layers 12. The number of packing layers 12 is multiple and arranged horizontally, the same as in embodiment 3. Correspondingly, the multiple ceramic membrane substrates 11 are all arranged vertically. This embodiment is actually similar to embodiment 2, if the following is removed... Figure 7 The outermost packing layer is the arrangement of the two basic units in Example 2. In this embodiment, the outermost packing layer can extend all the way to the inner wall of the purification unit's housing, achieving the same technical effect as in Example 3. Compared to Example 3, it is more suitable for conditions with high oil content in the feed liquid and high levels of harmful substances dissolved in the aqueous phase, effectively increasing the feed liquid processing capacity of the purification unit.

[0063] Example 5

[0064] like Figure 8 , 11As shown, the liquid-feed combination purification unit 1 in this embodiment is based on embodiment 3, with each basic unit arranged horizontally, and one of the filler layers removed from one side, as in embodiment 4. The ceramic membrane substrate 11 in this embodiment is still plate-shaped and serves as the partition between the filler layers 12. Multiple filler layers 12 are arranged horizontally, similar to embodiment 4. Correspondingly, the multiple ceramic membrane substrates 11 are arranged vertically. The outermost filler layer in this embodiment can extend to the inner wall of the purification unit's shell, while the other side can use the ceramic membrane substrate 11 as the wall surface. This embodiment achieves the same technical effects as embodiment 4. Compared to embodiment 3, it is more suitable for conditions with high oil content in the liquid and high levels of harmful substances dissolved in the aqueous phase, and can also effectively increase the liquid-feed processing capacity of the purification unit.

[0065] Example 6

[0066] like Figure 12 As shown, the ceramic membrane substrate 11 in this embodiment is a hollow cylinder and serves as the outer wall of the filler layer 12, with the hollow portion acting as the filler layer. Both the top and bottom surfaces of the filler layer 12 are inverted conical surfaces, and the range of the cone angle is preferably the same as the V-shaped angle range in Embodiment 1. The ceramic membrane substrate 11 has a certain thickness and uniformly spaced feed channels 111. The direction of the feed is the same as in the aforementioned embodiments. Unlike the plate-shaped ceramic membrane substrate 11 in the aforementioned embodiments, the ceramic membrane substrate 11 in this embodiment is actually an annular plate. With this structural design, the direction of the degreased feed in the filler layer 12 is more concentrated and uniform, all radially inward. Compared to the flat ceramic membrane substrates of Embodiments 1-5, this embodiment can achieve higher efficiency in removing harmful substances from the aqueous phase when using the same volume of filler.

[0067] Example 7

[0068] like Figure 13 As shown, in this embodiment, the ceramic membrane substrate 11 is tubular and serves as the axis of the filler layer, with the filler layer 12 disposed around the ceramic membrane substrate 11; both the top and bottom surfaces of the filler layer 12 are conical surfaces. The range of the cone angle is preferably the same as the V-shaped angle range in Embodiment 1. In this embodiment, the tubular ceramic membrane substrate 11 is actually a relatively thin solid structure with a certain diameter, and multiple feed channels 111 are axially penetrating this solid structure, with the feed flow direction being the same as in the aforementioned embodiment. This embodiment uses a tubular ceramic membrane substrate disposed in the middle, with the filler layer disposed on the periphery. This structural design not only makes the ceramic membrane substrate easier to manufacture, but also effectively increases the volume of the filler layer, extending its outer edge all the way to the inner wall of the purification unit's shell, which can greatly increase the amount of harmful substances that can be treated in the aqueous phase.

[0069] In embodiments 1 to 7 above, the liquid inlet of the liquid-liquid combination purification unit 1 is located at the bottom of the channel 111 of the ceramic membrane substrate 11; the liquid outlet of the liquid-liquid combination purification unit 1 includes a first outlet located at the lowest point of the bottom surface of the packing layer 12 and a second outlet located at the top of the channel 111. The liquid at the first outlet is the purified liquid after degreasing and removal of harmful substances dissolved in the aqueous phase (entering the storage tank 2), and the liquid at the second outlet is the turbid liquid carrying grease that enters the circulation tank 3. That is, through the treatment of the liquid-liquid combination purification unit 1, a portion of the completely purified liquid enters the storage tank 2 for later use, while the other portion of the liquid carrying grease enters the circulation tank 3 for further purification.

[0070] like Figures 1 to 3 As shown in Figures 6 to 8, the present invention also provides a purification system using the aforementioned combined feed-liquid purification unit. In addition to the combined feed-liquid purification unit 1, the system also includes a storage tank 2, a circulation tank 3, and connecting pipelines such as a circulation pipeline 4, a clear liquid pipeline 5, a regulating pipeline 6, a pre-membrane pipeline 7, and a backflushing pipeline 8. The storage tank 2 is connected to the aforementioned first outlet of the purification unit 1 and is used to store the purified feed liquid after degreasing and removal of harmful substances dissolved in the aqueous phase (the purified feed liquid enters the storage tank via the clear liquid pipeline 5). The circulation tank 3 is connected to the aforementioned second outlet of the purification unit 1 via the circulation pipeline 4 and is used to receive turbid liquid carrying oil and pump the feed liquid to be purified to the feed inlet of the purification unit via the pre-membrane pipeline 7. Part of the purified feed liquid in the storage tank 2 can be used in downstream processes via the first outlet pipeline 21, and another part can be sent to the circulation tank 3 via the regulating pipeline 6 to adjust the feed concentration. Preferably, but not limitingly, the flow rate ratio of the regulating pipe 6 to the flow rate of the first feed pipe 31 for external feeding can be 0 to 0.5. Furthermore, the storage tank 2 can also be used to introduce a portion of the purified liquid from the bottom of the packing layer 12 after the system has been running for a long time, and then backwash the ceramic membrane disposed on the inner wall of the channel 111 via the ceramic membrane substrate 11. This invention allows for membrane regeneration during purification intermittently, requiring only one membrane filtration unit to achieve continuous feeding; the purified liquid generated by the system's internal purification unit is used to backwash and regenerate the ceramic membrane, eliminating the need for an external water source, and the regenerated waste liquid is diluted and filtered again in the next cycle, preventing the generation of additional regeneration waste and making it more environmentally friendly.

[0071] This invention also provides a purification and regeneration method using the aforementioned purification system. This method is used for the pretreatment of oily raw materials without solid particles and includes the following steps:

[0072] Step S101: Pump the liquid to be purified into each channel 111 of the ceramic membrane substrate 11 adjacent to the packing layer 12;

[0073] In step S102, the liquid in the channel retains the free oil in the channel 111 under the action of the ceramic membrane, while the aqueous phase in the liquid permeates through the ceramic membrane substrate 11 to the adjacent filler layer 12.

[0074] In step S103, the oil-removed aqueous phase adsorbs harmful substances dissolved in the aqueous phase through the packing layer 12, and the purified liquid is obtained at the first outlet and stored in the storage tank 2.

[0075] In step S104, the turbid liquid carrying the grease trapped in step S102 enters the circulation tank 3 through the second discharge port for circulation. When the grease concentration in the circulation tank 3 is too high, it can be discharged from the system through the second discharge pipe 32.

[0076] In step S105, after the system has been running for a long time, the purified liquid in the storage tank 2 is introduced from the bottom of the packing layer 12 and then backwashed through the ceramic membrane substrate onto the ceramic membrane located on the inner wall of the channel 111 for membrane regeneration. In this step, preferably but not limitingly, when the adsorption concentration in the packing layer 12 is too high, a high-concentration cleaning agent (ethanol or acetone, etc.) can also be introduced into the backwashing pipeline 8 through the second feed pipeline 9.

[0077] The purification and regeneration method of the present invention can not only effectively purify the grease and water-soluble harmful substances in the feed liquid in the same purification unit, but also use the purified feed liquid in the system to complete the regeneration of the ceramic membrane without the need for external water sources. Moreover, the regenerated waste liquid can be recycled and purified without generating additional regeneration waste, resulting in better environmental performance.

[0078] The foregoing description of specific exemplary embodiments of the present invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. Any simple modifications, equivalent changes, and alterations made to the foregoing exemplary embodiments should fall within the scope of protection of the present invention.

Claims

1. A feed solution combination purification unit, characterized in that, The application relates to a purification system for oil-containing raw materials, comprising: a ceramic membrane base for oil removal treatment of a feed liquid and provided with a plurality of channels extending vertically along the base, the channels serving as inlet channels for the feed liquid purification, and ceramic membranes being sintered on the inner walls of the channels; a filler layer provided adjacent to the ceramic membrane base and combined into a purification unit, for receiving the feed liquid after oil removal and adsorbing harmful substances dissolved in the water phase.

2. The feed solution combination purification unit of claim 1, wherein, The ceramic membrane base is plate-shaped, serving as a partition wall or wall surface of the filler layer.

3. The feed solution combination purification unit of claim 2, wherein, When the ceramic membrane base is plate-shaped and serves as a wall surface of the filler layer, the filler layers are multiple and arranged transversely, and the top surface and the bottom surface of each filler layer are V-shaped; correspondingly, the ceramic membrane bases are vertically arranged.

4. The feed solution combination purification unit of claim 2, wherein, When the ceramic membrane base is plate-shaped and serves as a partition wall of the filler layer, the filler layers are multiple and arranged transversely, and the top surface and the bottom surface of each filler layer are inverted V-shaped; correspondingly, the ceramic membrane bases are single or multiple and vertically arranged.

5. The feed solution combination purification unit of claim 1, wherein, The ceramic membrane base is hollow-cylindrical and serves as an outer wall surface of the filler layer, and the hollow part serves as the filler layer; the top surface and the bottom surface of the filler layer are inverted conical.

6. The feed solution combination purification unit of claim 1, wherein, The ceramic membrane base is tubular and serves as the axis of the filler layer, and the filler layer is arranged on the periphery of the ceramic membrane base; the top surface and the bottom surface of the filler layer are normal conical.

7. The feed solution combination purification unit of claim 1, wherein, The feed liquid inlet is arranged at the bottom of the channel; the feed liquid outlet comprises a first outlet arranged at the lowest point of the bottom surface of the filler layer and a second outlet arranged at the top of the channel; the feed liquid of the first outlet is the purified feed liquid after oil removal and removal of harmful substances dissolved in the water phase, and the feed liquid of the second outlet is the turbid liquid carrying oil and entering the circulating tank.

8. The feed solution combination purification unit of claim 3, wherein, The angle between the bottom surface of the filler layer and the vertical center line of the filler layer is 30 DEG < alpha < 60 DEG ; the angle between the top surface of the filler layer and the ceramic membrane base is 30 DEG < alpha' < 60 DEG.

9. The feed solution combination purification unit of claim 4, wherein, The angle between the bottom surface of the filler layer and the vertical outer edge of the filler layer is 30 DEG < alpha < 60 DEG ; the angle between the top surface of the filler layer and the ceramic membrane base is 30 DEG < alpha' < 60 DEG.

10. A feed solution combination purification system, characterized in that, The purification unit is applied to the system.

11. The feed solution combination purification system of claim 10, wherein, Further comprising: a liquid storage tank in communication with the first outlet of the purification unit, for storing the purified feed liquid after oil removal and removal of harmful substances dissolved in the water phase; a circulating tank in communication with the second outlet of the purification unit, for receiving the turbid liquid carrying oil and pumping the feed liquid to be purified to the feed liquid inlet of the purification unit.

12. The feed solution combination purification system of claim 11, wherein, Part of the purified feed liquid in the liquid storage tank is used in the downstream process, and the other part is sent to the circulating tank through an adjusting pipeline for adjusting the feed concentration.

13. The feed solution combination purification system of claim 12, wherein, The flow ratio of the adjusting pipeline to the first feed pipeline of the external feed is 0-0.

5.

14. The feed solution combination purification system of claim 12, wherein, The liquid storage tank is also used for introducing the purified feed liquid from the bottom of the filler layer, and then reversely flushing the ceramic membranes arranged on the inner walls of the channels through the ceramic membrane base.

15. A method for purifying and regenerating a feed solution combination, characterized by, The system is applied to the pretreatment of oil-containing raw materials without solid particles, comprising the following steps: A. Pumping the feed liquid to be purified into each channel of the ceramic membrane base provided adjacent to the filler layer; B. The feed liquid in the channel leaves the free oil under the action of the ceramic membrane, and the water phase in the feed liquid penetrates into the adjacent filler layer through the ceramic membrane base. C. The water phase is adsorbed by the filler layer to adsorb harmful substances dissolved in the water phase, and purified liquid is obtained at the first discharge port and stored in a storage tank; D. The turbid liquid carrying the oil and fat is introduced into the circulating tank through the second discharge port for circulation; E. After the system is operated for a long time, the purified liquid in the storage tank is introduced from the bottom of the filler layer, and then the ceramic membrane provided on the inner wall of the channel is backwashed through the ceramic membrane base to regenerate the membrane.

16. The feed solution combination purification regeneration method according to claim 15, characterized by, The step E further includes: When the adsorption concentration in the filler layer is too high, a high-concentration cleaning agent is introduced into the backwashing pipeline through the second feeding pipeline.

17. The feed solution combination purification regeneration method according to claim 16, characterized by, The high-concentration cleaning agent is ethanol or acetone.

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