Bidirectional oil-water filtering membrane bag

Abstract

The utility model belongs to the technical field of membrane filtration, and particularly relates to a bidirectional oil-water filtering membrane bag. The utility model comprises: a film-coated substrate; the hydrophilic membrane end cover is arranged on one side of the membrane package base body, a hydrophilic membrane is arranged between the hydrophilic membrane end cover and the membrane package base body, and the hydrophilic membrane is attached to the membrane package base body; the hydrophobic membrane end cover is arranged on the other side of the membrane package base body, a hydrophobic membrane is arranged between the hydrophobic membrane end cover and the membrane package base body, and the hydrophobic membrane is attached to the membrane package base body; a liquid inlet and a waste liquid opening are formed in the membrane package base body and correspond to the position between the hydrophilic membrane and the hydrophobic membrane; a first liquid outlet is formed in the hydrophilic membrane end cover, and a second liquid outlet is formed in the hydrophobic membrane end cover; and the distance between the hydrophilic membrane and the hydrophobic membrane ranges from 3 mm to 80 mm. The utility model is used for solving the technical problems that only a single water-phase or oil-phase product can be obtained by the existing membrane separation technology, oil-water mixed excrement is accompanied, and the filtering effect cannot be further improved.

Description

Technical Field

[0001] This utility model belongs to the field of membrane filtration technology, specifically relating to a bidirectional oil-water filtration membrane pack. Background Technology

[0002] Oily wastewater is widely recognized as one of the most serious threats to Earth's ecosystems and water resources in daily life and industrial processes. Over the past decade, significant progress has been made in both basic research and industrial applications for treating oily wastewater, aiming to improve water quality and recover valuable oil resources. Mainstream treatment methods include mechanical skimming, flotation, centrifugation, chemical flocculation, electrocoagulation, and membrane separation technology. Among these, membrane separation technology, due to its high separation efficiency, low energy consumption, and low chemical usage, has become the benchmark tool for treating various types of oily wastewater and even surfactant-stabilized emulsions.

[0003] However, despite substantial progress in developing membrane materials and devices for treating oily wastewater, achieving the simultaneous and efficient recovery of both oil and water from surfactant-stabilized emulsions remains a historic challenge. Existing membrane separation technologies typically yield only a single aqueous or oil phase, accompanied by an oil-water mixture, falling far short of the near-zero liquid discharge target. Utility Model Content

[0004] This invention provides a bidirectional oil-water filtration membrane pack to solve the technical problem that existing membrane separation technologies can only obtain a single aqueous or oil phase product, and are accompanied by oil-water mixed excrement, which cannot further improve the filtration effect.

[0005] This utility model includes:

[0006] Membrane-coated substrate;

[0007] A hydrophilic membrane end cap is disposed on one side of the membrane substrate, and a hydrophilic membrane is provided between the hydrophilic membrane end cap and the membrane substrate, the hydrophilic membrane being attached to the membrane substrate;

[0008] A hydrophobic membrane end cap is disposed on the other side of the membrane substrate, and a hydrophobic membrane is provided between the hydrophobic membrane end cap and the membrane substrate, the hydrophobic membrane being attached to the membrane substrate;

[0009] The membrane substrate is provided with an inlet and a waste outlet, which are located between the hydrophilic membrane and the hydrophobic membrane.

[0010] The hydrophilic membrane end cap is provided with a first liquid outlet, and the hydrophobic membrane end cap is provided with a second liquid outlet;

[0011] The distance between the hydrophilic membrane and the hydrophobic membrane ranges from 3 to 80 mm.

[0012] This invention constructs a narrow slit region using hydrophilic and hydrophobic membranes. When the emulsion enters this narrow slit region, the emulsion achieves simultaneous bidirectional separation of oil and water within the confined space.

[0013] Furthermore: a first metal sintered filter sheet is provided between the hydrophilic membrane end cap and the hydrophilic membrane;

[0014] A second sintered metal filter is provided between the hydrophobic membrane end cap and the hydrophobic membrane. The beneficial effect of this step is that the first sintered metal filter and the second sintered metal filter support the hydrophilic membrane and the hydrophobic membrane respectively, so as to avoid deformation and damage of the hydrophilic membrane and the hydrophobic membrane.

[0015] Furthermore: the pore size range of the hydrophilic membrane is 0.1~8µm, and the pore size range of the hydrophobic membrane is 0.01~3µm;

[0016] The pore size range of the first metal sintered filter and the second metal sintered filter is 8~100um. The beneficial effect of this step is that the micron-sized pore size combined with the hydrophilicity and hydrophobicity of the membrane surface enables oil-water separation.

[0017] Furthermore, both the hydrophilic membrane end cap and the hydrophobic membrane end cap have flow guiding cavities on their inner sides. The beneficial effect of this step is that the flow guiding cavities serve to guide and output the flow.

[0018] Furthermore, both the hydrophilic membrane end cap and the hydrophobic membrane end cap have flow direction markings on their surfaces. The benefits of this step are: to prevent the manufacturer from installing the hydrophilic membrane end cap and the hydrophobic membrane end cap incorrectly, and to remind the user to use them correctly.

[0019] Furthermore, the membrane substrate, the hydrophilic membrane end cap, and the hydrophobic membrane end cap are provided with a number of fixing grooves on their circumferential surfaces. The beneficial effect of this step is that the bidirectional oil-water filter membrane package can be fixedly installed through the fixing grooves, avoiding situations such as falling off or shifting during use.

[0020] The beneficial effects of this utility model are:

[0021] This application utilizes a slit space constructed from hydrophilic and hydrophobic membranes to continuously squeeze in the emulsion, allowing the aqueous and oil phases within the emulsion to separate from the hydrophilic and hydrophobic membrane sides, respectively, thus achieving simultaneous oil-water separation. Furthermore, this application also features low energy consumption and reusability. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 A perspective view of a bidirectional oil-water filtration membrane pack provided by this utility model;

[0024] Figure 2 An exploded view of a bidirectional oil-water filtration membrane package provided by this utility model;

[0025] Figure 3 A cross-sectional view of a bidirectional oil-water filtration membrane package provided by this utility model;

[0026] Figure 4 for Figure 3 A magnified view of part A in the middle.

[0027] Figure label:

[0028] 1- Membrane substrate; 2- Hydrophilic membrane end cap; 3- Hydrophobic membrane end cap; 4- Liquid inlet; 5- Waste liquid outlet; 6- First liquid outlet; 7- Second liquid outlet; 8- Flow direction mark; 9- Hydrophilic membrane; 10- Hydrophobic membrane; 11- First sintered metal filter; 12- Second sintered metal filter; 13- Flow guiding cavity; 14- Slit area; 15- Fixing groove. Detailed Implementation

[0029] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0030] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application shall have the ordinary meaning as understood by one of ordinary skill in the art to which this utility model pertains.

[0031] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly defined.

[0032] This application implements, for example Figures 1-4 As shown, a bidirectional oil-water filtration membrane pack is provided, which can simultaneously separate the oil phase and the water phase of an emulsion.

[0033] This utility model includes:

[0034] Membrane-coated substrate 1;

[0035] A hydrophilic membrane end cap 2 is disposed on one side of the membrane substrate 1, and a hydrophilic membrane 9 is provided between the hydrophilic membrane end cap 2 and the membrane substrate 1, the hydrophilic membrane 9 being attached to the membrane substrate 1;

[0036] A hydrophobic membrane end cap 3 is disposed on the other side of the membrane substrate 1, and a hydrophobic membrane 10 is provided between the hydrophobic membrane end cap 3 and the membrane substrate 1, the hydrophobic membrane 10 being attached to the membrane substrate 1.

[0037] The membrane substrate 1 is provided with an inlet 4 and a waste outlet 5, the inlet 4 and the waste outlet 5 corresponding to the slit region 14 between the hydrophilic membrane 9 and the hydrophobic membrane 10;

[0038] The hydrophilic membrane end cap 2 is provided with a first liquid outlet 6, and the hydrophobic membrane end cap 3 is provided with a second liquid outlet 7;

[0039] The distance between the hydrophilic membrane 9 and the hydrophobic membrane 10 ranges from 3 to 80 mm.

[0040] This invention constructs a slit region 14 using a hydrophilic membrane 9 and a hydrophobic membrane 10. When the emulsion enters this slit region 14, the emulsion achieves simultaneous bidirectional separation of oil and water within the confined space. Specifically, the "squeezing" effect of the slit region 14 plays a crucial role in the demulsification and separation of emulsion droplets.

[0041] Taking the separation of oil-in-water emulsions as an example, within the slit region 14, as water is discharged from the hydrophilic membrane 9, the local concentration of emulsion droplets in the oil-in-water emulsion rapidly increases. Simultaneously, the slit region 14 further enhances the collision probability of the emulsion droplets. The synergistic effect of these two factors significantly strengthens the "concentration-agglomeration-demulsification-separation" process of the emulsion.

[0042] The removal of the aqueous phase from the hydrophilic membrane 9 increases the emulsion concentration, promoting droplet collision, coalescence, and demulsification, thereby enhancing the permeation flux of the oil phase. Simultaneously, the continuous removal of the oil phase helps reduce the emulsion concentration at the membrane surface, thus mitigating the inhibitory effect of concentration polarization on the permeation flux of the hydrophilic membrane 9. This process creates a positive feedback mechanism, significantly improving the simultaneous separation efficiency.

[0043] In this embodiment, the membrane substrate 1 and the end caps at both ends can be planar seals or axial seals, and the end caps are connected to the membrane substrate 1 through sealing rings or similar sealing elements. The membrane substrate 1 and the end caps can be flange-type sealing structures or socket-type sealing structures.

[0044] In one embodiment, a first metal sintered filter 11 is provided between the hydrophilic membrane end cap 2 and the hydrophilic membrane 9;

[0045] A second metal sintered filter 12 is provided between the hydrophobic membrane end cap 3 and the hydrophobic membrane 10. The first metal sintered filter 11 and the second metal sintered filter 12 are used to support the hydrophilic membrane 9 and the hydrophobic membrane 10 respectively, so as to prevent the hydrophilic membrane 9 and the hydrophobic membrane 10 from being deformed or damaged.

[0046] In one embodiment, the pore size of the hydrophilic membrane 9 ranges from 0.1 to 8 μm, and the pore size of the hydrophobic membrane 10 ranges from 0.01 to 3 μm.

[0047] The pore size range of the first metal sintered filter 11 and the second metal sintered filter 12 is 8~100um. The micron-sized pore size is suitable for the diameter of the water phase and oil phase particles in the emulsion. Combined with the hydrophilicity and hydrophobicity of the membrane surface, oil-water separation is achieved. The pore size of the first metal sintered filter 11 and the second metal sintered filter 12 is larger than the pore size of the membrane, which will not affect the membrane filtration effect.

[0048] The hydrophilic membrane is typically made of polyethersulfone (PES), polyacrylonitrile (PAN), or a hydrophilically modified polymer (such as a polyvinyl alcohol PVA coating).

[0049] Hydrophobic membranes are commonly made of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyethylene (PE), polypropylene (PP), or materials modified with superhydrophobicity (such as nano-silica coatings).

[0050] In one embodiment, both the hydrophilic membrane end cap 2 and the hydrophobic membrane end cap 3 are provided with a flow guiding cavity 13 on their inner sides. The flow guiding cavity 13 is a curved structure that gradually increases in size. The flow guiding cavity 13 near the liquid inlet 4 has a small space, while the flow guiding cavity 13 near the first liquid outlet 6 or the second liquid outlet 7 has a large space. The flow guiding cavity 13 plays the role of guiding and outputting the liquid.

[0051] In one embodiment, both the hydrophilic membrane end cap 2 and the hydrophobic membrane end cap 3 are provided with flow direction markings 8. The flow direction markings 8 can specify the direction of use and installation, so as to prevent the hydrophilic membrane end cap 2 and the hydrophobic membrane end cap 3 from being installed incorrectly by the manufacturer, and to prompt the user to use them correctly.

[0052] In one embodiment, the periphery of the membrane substrate 1, the hydrophilic membrane end cap 2, and the hydrophobic membrane end cap 3 are provided with a plurality of fixing grooves 15. The bidirectional oil-water filter membrane pack can be fixedly installed by means of fixing grooves 15 and parts such as limiting rods, so as to avoid detachment or displacement during use.

[0053] This invention relates to the simultaneous recovery of the oil and aqueous phases in surfactant-stabilized oil-water emulsions, achieving high-purity separation and near-zero liquid discharge. This technology can be widely applied in petrochemicals, marine oil spill remediation, industrial wastewater treatment, and resource recovery.

[0054] The working mode of this utility model for separating emulsions is as follows: the output end of a peristaltic pump or diaphragm pump is connected to the inlet 4. The working fluid, i.e., the emulsion, is divided into three outlets within the membrane capsule. Clean water flows out through the first outlet 6 on the hydrophilic membrane 9 side; oil and water flow out through the second outlet 7 on the hydrophobic membrane 10 side; and the unseparable waste liquid flows out through the waste outlet 5, thus constituting a novel application mode for simultaneous oil-water separation. The outflowing waste liquid can also be recycled back into the membrane capsule for cyclic filtration, achieving maximum oil-water separation.

[0055] Numerous specific details are set forth in this specification. However, it will be understood that embodiments of this invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification. In the description of this specification, references to the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model, and they should all be covered within the scope of the claims and specification of this utility model.

Claims

1. A bidirectional oil-water filtration membrane pack, characterized in that, include: Membrane-coated substrate; A hydrophilic membrane end cap is disposed on one side of the membrane substrate, and a hydrophilic membrane is provided between the hydrophilic membrane end cap and the membrane substrate, the hydrophilic membrane being attached to the membrane substrate; A hydrophobic membrane end cap is disposed on the other side of the membrane substrate, and a hydrophobic membrane is provided between the hydrophobic membrane end cap and the membrane substrate, the hydrophobic membrane being attached to the membrane substrate; The membrane substrate is provided with an inlet and a waste outlet, which are located between the hydrophilic membrane and the hydrophobic membrane. The hydrophilic membrane end cap is provided with a first liquid outlet, and the hydrophobic membrane end cap is provided with a second liquid outlet; The distance between the hydrophilic membrane and the hydrophobic membrane ranges from 3 to 80 mm; A first metal sintered filter sheet is provided between the hydrophilic membrane end cap and the hydrophilic membrane; A second metal sintered filter sheet is provided between the hydrophobic membrane end cap and the hydrophobic membrane; The hydrophilic membrane has a pore size range of 0.1~8 μm, and the hydrophobic membrane has a pore size range of 0.01~3 μm. The pore size range of the first metal sintered filter and the second metal sintered filter is 8~100um; Both the hydrophilic membrane end cap and the hydrophobic membrane end cap have flow guiding cavities on their inner sides.

2. The bidirectional oil-water filtration membrane pack according to claim 1, characterized in that, Both the hydrophilic membrane end cap and the hydrophobic membrane end cap have flow direction markings on their surfaces.

3. The bidirectional oil-water filtration membrane pack according to claim 1, characterized in that, The membrane substrate, the hydrophilic membrane end cap, and the hydrophobic membrane end cap are provided with a number of fixing grooves on their respective peripheral surfaces.

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