A method for preparing a reverse osmosis membrane

Abstract

A preparation method of a reverse osmosis membrane is provided with a reverse osmosis membrane, a front end cover, a rear end cover, a center tube and an outer cylinder. The method comprises the following steps: folding the reverse osmosis membrane around the center tube into a ring structure with petals, marking first and second pressing marks on the outer side of the two sides of the petals, marking third and fourth pressing marks on the inner side of the two sides of the petals, coating adhesive on the first and third pressing marks, pressing and bonding the first and second pressing marks of each adjacent petal together, pressing and bonding the third and fourth pressing marks of each petal together, bonding the two side openings of each petal together, bonding the two ends of the reverse osmosis membrane together, placing the center tube into the center hole of the reverse osmosis membrane column, and bonding and sealing the two end portions of the center hole of the reverse osmosis membrane column to form a reverse osmosis membrane assembly. The method can improve the utilization rate of the reverse osmosis membrane and improve the filtering effect of water purification.

Description

Technical Field

[0001] This invention relates to a filtration technology, and more particularly to a method for preparing a reverse osmosis membrane. Background Technology

[0002] Water purification is a crucial technology for improving the human living environment on Earth. In today's increasingly industrialized world, wastewater treatment, domestic water purification, and technologies for obtaining water resources from polluted areas through water purification are essential for humanity's continued survival on this planet. Among water purification technologies, reverse osmosis membrane technology is one of the most economical and effective methods. A reverse osmosis membrane is an artificial semi-permeable membrane with specific characteristics, mimicking a biological semi-permeable membrane, and is the core component of reverse osmosis technology. The principle of reverse osmosis is based on the principle that under pressure higher than the osmotic pressure of the solution, substances that cannot pass through the semi-permeable membrane are separated from water. The membrane pore size of a reverse osmosis membrane is extremely small, thus effectively removing dissolved salts, colloids, microorganisms, and organic matter from water. It has advantages such as good water quality, low energy consumption, no pollution, simple process, and easy operation. Reverse osmosis membrane devices generally adopt a roll-up structure. After the water enters at the front end, the reverse osmosis membrane, through winding, separates the purified product water and the concentrated water containing contaminants; the product water is collected to obtain new water resources.

[0003] However, existing roll-up reverse osmosis membrane devices mainly use a structure where layers are folded and stacked around a central column. This folding divides the container space within the high-pressure chamber into two parts. Raw water enters from the outside, passes through one layer of reverse osmosis membrane, and then enters the inside, completing the filtration process. The filtered water is then output from the central column pipe. This design only allows for the filtration of a single reverse osmosis membrane. While some products achieve filtration with two overlapping reverse osmosis membranes, this results in a thicker single leaf formed by the folds, affecting the precise fit of each fold. Furthermore, it necessitates an additional spacer between each layer, reducing the overall roll-up area of ​​the reverse osmosis membrane and impacting its filtration efficiency. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a method for preparing a reverse osmosis membrane, which uses one layer of reverse osmosis membrane to form a multi-layer osmosis membrane filtration effect, thereby improving the efficiency of reverse osmosis membrane and enhancing its filtration effect.

[0005] The technical solution of this invention is:

[0006] A method for preparing a reverse osmosis membrane, comprising a reverse osmosis membrane, a front end cap, a rear end cap, a central tube, and an outer cylinder; including the following steps:

[0007] 1. Cut the reverse osmosis membrane into a specified length and width, the width of which is less than the inner length of the outer cylinder; fold it around the central tube into a petal-shaped structure with petals, each petal rotating around the central tube in one direction and pressing against each other;

[0008] 2. A first pressing mark and a second pressing mark are marked on the outer surfaces of both sides of the petal, respectively. The first pressing mark of the former petal corresponds to and is attached to the second pressing mark of the latter petal. A third pressing mark and a fourth pressing mark are marked on the inner surfaces of both sides of the petal, respectively. The third pressing mark and the fourth pressing mark are attached to the inner side of the same petal. The third pressing mark and the fourth pressing mark are located on the inner side of the first pressing mark and the second pressing mark towards the central tube.

[0009] 3. Apply adhesive to each of the first and third pressing marks, press and bond the first pressing marks of each front lobe and the second pressing marks of each rear lobe together in sequence, and press and bond the third and fourth pressing marks on the inner side of each lobe together in sequence.

[0010] 4. Adhere the two openings on both sides of each of the aforementioned petals together, and adhere the two ends of the reverse osmosis membrane together to form a reverse osmosis membrane column;

[0011] 5. Place the central tube into the central hole of the reverse osmosis membrane column, and seal the two ends of the central hole of the reverse osmosis membrane column to form a reverse osmosis membrane module.

[0012] 6. Install the reverse osmosis membrane module into the outer cylinder, install the front end cap at the inlet end, and install the rear end cap at the outlet end.

[0013] The reverse osmosis membrane preparation method described above further includes, after step three: inserting a spacer into the first and second inner cavities of the valve, which are separated by a third and a fourth pressure mark.

[0014] The reverse osmosis membrane preparation method described above further includes, after step three: inserting a spacer into the inner first lobe cavity formed after the first and second pressure marks adhere together.

[0015] The reverse osmosis membrane preparation method described above further includes, after step four, inserting a spacer at the interval between the two lobes outside the adhesion point of the first and second pressure marks.

[0016] As can be seen from the above description, the present invention does indeed have the following advantages:

[0017] The reverse osmosis membrane preparation method of this invention is the same as that of conventional reverse osmosis membrane assemblies that are layered and wound around a central tube, except that a single reverse osmosis membrane is used for folding and winding. This results in a large number of leaf-like layers and a larger filtration and purification area. Furthermore, this invention provides pressure marks on the outer and inner sides of each leaf to block water flow, dividing each leaf into multiple cavities. Each cavity has a gradually decreasing internal pressure depending on its distance from the central tube. Raw water flows from the outermost layer along an S-shaped path into the innermost wall closest to the central tube. Thus, the water flows from the outside to the inside through multiple reverse osmosis membranes, achieving multiple filtration processes. Therefore, this invention achieves multiple filtration processes without increasing the number of reverse osmosis membranes, greatly improving the filtration efficiency of the reverse osmosis membrane device. At the same time, since the water flows through the multiple segments of the reverse osmosis membrane that are dusted, the entire reverse osmosis membrane of each segment can be utilized from the outside to the inside. Unlike typical reverse osmosis membrane devices, where the reverse osmosis membrane near the outer cylinder is used more efficiently while the reverse osmosis membrane near the center tube is less efficient, the overall utilization rate of the reverse osmosis membrane is improved in essence. Attached Figure Description

[0018] Figure 1 This is a flowchart illustrating the method steps of a preferred embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of the reverse osmosis membrane folding and pressing marks according to a preferred embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram illustrating the analogous structure of the water flow channel of a reverse osmosis membrane module according to a preferred embodiment of the present invention.

[0021] Figure 4 This is a schematic diagram of the water flow channel analogy structure of multiple sets of pressure marks in a preferred embodiment of the present invention.

[0022] Explanation of key component designations:

[0023] This invention:

[0024] 1: Central tube; 2: Reverse osmosis membrane; 3: Valve.

[0025] 31: First pressing mark; 32: Second pressing mark; 33: Third pressing mark

[0026] 34: Fourth pressing mark 4: Pressing mark Detailed Implementation

[0027] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0028] The present invention proposes a method for preparing a reverse osmosis membrane. It adopts a structure similar to that of existing reverse osmosis membrane devices that are wound and rotated around a central tube. However, it further incorporates a substantial innovative design, enabling each flap 3 and the area between flaps 3 to have multiple filtration chambers. This achieves a reverse osmosis membrane assembly structure that allows water to pass through the reverse osmosis membrane multiple times for filtration. It also fundamentally solves the problem that the reverse osmosis membrane near the outer tube is easily fouled and aged due to overuse, while the reverse osmosis membrane near the central tube has a low utilization rate. As a result, the reverse osmosis membrane filtration structure prepared by the present invention has a higher overall utilization efficiency.

[0029] A preferred embodiment of the method for preparing a reverse osmosis membrane according to the present invention is described below. Figures 1 to 3 As shown, the invention comprises a reverse osmosis membrane 2, a central tube 1, a front end cap, a rear end cap, and an outer cylinder; preferably, the invention includes the following steps:

[0030] Step S101: Cut the reverse osmosis membrane to a specified length and width, with the width being less than the inner length of the outer cylinder. Fold it around the central tube 1 to form a petal-shaped structure with petals 3. Each petal 3 rotates around the central tube 1 in one direction and presses against each other. Preferably, the reverse osmosis membrane 2 is a long strip of fabric-like structure, which is folded in an S-shape, with one side completely close to the central tube 1. After folding and pressing, it forms a solid cylinder-like structure. After folding and pressing, fold marks are left at the folding points of each petal 3 to facilitate further folding according to these marks. Of course, after folding in step one, it is slightly loosened for subsequent processing steps.

[0031] In step S102, a first pressing mark 31 and a second pressing mark 32 are marked on the outer surfaces of both sides of the flap 3, respectively. The first pressing mark 31 of the former flap 3 corresponds to the second pressing mark 32 of the latter flap 3. A third pressing mark 33 and a fourth pressing mark 34 are marked on the inner surfaces of both sides of the flap 3, respectively. The third pressing mark 33 and the fourth pressing mark 34 correspond to each other on the inner side of the same flap 3. The third pressing mark 33 and the fourth pressing mark 34 are located on the inner side of the first pressing mark 31 and the second pressing mark 32 towards the central tube 1. Preferably, the first pressing mark 31, the second pressing mark 32, the third pressing mark 33 and the fourth pressing mark 34 can be processed by imprinting, for example, by clamping these pressing marks with clamps of corresponding length. Of course, before processing, the positions of each pressing mark 4 can be marked before unfolding the reverse osmosis membrane 2 to perform the pressing mark 4 operation. The pressing mark 4 can be a smooth, strip-shaped mark with a width of 1-2 mm after being pressed. The structure at the pressed location changes, becoming denser and smoother, significantly reducing its water permeability. As shown in the figure, the first pressing mark 31 and the second pressing mark 32 are located on the side of the petal 3 near the outer cylinder, while the third pressing mark 33 and the fourth pressing mark 34 are located on the side of the first pressing mark 31 and the second pressing mark 32 near the central tube 1. The first pressing mark 31 and the second pressing mark 32 are used for corresponding adhesion on the outside of the petal 3, while the third pressing mark 33 and the fourth pressing mark 34 are used for corresponding adhesion on the inside of the petal 3.

[0032] Step S103: Apply adhesive to each of the first pressing marks 31 and the third pressing marks 33, and press and bond the first pressing marks 31 of each front lobe 3 and the second pressing marks 32 of each rear lobe 3 together in sequence. Also, press and bond the third pressing marks 33 and the fourth pressing marks 34 on the inner side of each lobe 3 together in sequence. As shown in the figure, the first pressing marks 31 and the second pressing marks 32 of two adjacent lobe 3 are bonded together with the specified adhesive. After bonding, the bonding area of ​​the first pressing marks 31 and the second pressing marks 32 will not loosen due to water immersion, and the bonding area is waterproof, thus preventing water from passing through. This allows for the creation of a first outer cavity near the central tube 1 between adjacent petals 3. Similarly, after the third and fourth pressing marks 33 within the same petal 3 are joined, the interior of the petal 3 is divided into a first inner cavity and a second inner cavity, providing an S-shaped water flow path from the outer cylinder side to the central tube 1 side. In this path, the raw water must pass through three reverse osmosis membranes 2 to reach the central tube 1 side. These three reverse osmosis membranes 2 are all composed of the sidewalls of the petals 3 of the reverse osmosis membrane 2. This ensures efficient utilization of the entire petal 3 of the reverse osmosis membrane 2 from the outer cylinder direction to the central tube 1 direction. Figure 3 and Figure 4As can be seen from the analogous structural diagram, the water flow channel follows a continuous S-shaped flow path on one side of a petal 3 to filter through each reverse osmosis membrane segment.

[0033] Step S104: Adhere the two openings on both sides of each of the petals 3 together, and adhere the two ends of the reverse osmosis membrane 2 together to form a reverse osmosis membrane column.

[0034] Step S105: Place the central tube 1 into the central hole of the reverse osmosis membrane column, and seal the two ends of the central hole of the reverse osmosis membrane column to form a reverse osmosis membrane assembly.

[0035] Preferably, in steps four and five, similar to conventional reverse osmosis membrane sealing, the openings on both sides of the flap 3 are glued and sealed, and the two ends connecting the reverse osmosis membrane column to the central tube 1 are sealed, so that a sealed space is formed inside the reverse osmosis membrane 2.

[0036] Step S106: Install the reverse osmosis membrane module into the outer cylinder, install the front end cap at the inlet end, and install the rear end cap at the outlet end. Preferably, the preparation of the entire reverse osmosis membrane is completed by installing the reverse osmosis membrane module into the outer cylinder and fixing the front and rear end caps to the inlet and outlet ends of the outer cylinder. The reverse osmosis membrane prepared by this invention can effectively improve the overall utilization rate of the reverse osmosis membrane, and allows the raw water to undergo triple filtration before reaching the central pipe 1, resulting in a stronger filtration effect and higher purity of the filtered water.

[0037] In a preferred embodiment of the reverse osmosis membrane preparation method of the present invention as described above, after step three, a spacer is inserted into the first and second inner cavities of the flap 3, which are separated by a third pressing groove 33 and a fourth pressing groove 34. Preferably, as shown in the figure, inserting a spacer into the first and second inner cavities of the flap effectively provides space for the flow of filtered water, increasing the water production rate.

[0038] In a preferred embodiment of the reverse osmosis membrane preparation method of the present invention as described above, after step three, a spacer is inserted into the inner first outer cavity of the first petal formed after the first pressing groove 31 and the second pressing groove 32 are bonded together. As shown in the figure, inserting a spacer into the outer cavity of the petal can effectively provide space for the flow of filtered water and increase the water production rate.

[0039] In a preferred embodiment of the reverse osmosis membrane preparation method of the present invention as described above, after step four, a spacer is inserted at the interval between the two petals 3 outside the adhesion point of the first pressing mark 31 and the second pressing mark 32. As shown in the figure, inserting a spacer between adjacent petals 3 can provide a larger flow space for water and improve the water production rate.

[0040] Furthermore, before step three, the present invention can further provide another set of pressure marks between adjacent petals 3 and pressure marks on the inner side of petals 3 on the side of the third pressure mark 33 and the fourth pressure mark 34 near the central tube 1, as shown in the figure. This further transforms the water flow channel into a channel that needs to pass through five layers of reverse osmosis membrane 2 for filtration, further improving the filtration effect of the reverse osmosis membrane 2. Of course, if the pressure difference between the inlet and outlet can be increased, adding pressure mark sets to increase the number of times the reverse osmosis membrane 2 passes through the water flow channel can be selected according to the specific actual needs of use. Theoretically, as long as the width of the reverse osmosis membrane petals 3 is sufficient, it is possible to divide it into as many segments as possible to make fuller use of the entire reverse osmosis membrane 2 for filtration.

[0041] The preparation method of the reverse osmosis membrane of the present invention is the same as that of conventional reverse osmosis membrane assemblies that are layered and wound around a central tube 1, except that a single reverse osmosis membrane 2 is used for folding and winding. This results in a large number of petal layers 3 obtained by folding the reverse osmosis membrane 2, providing a larger filtration and purification area. Furthermore, the present invention provides pressure marks 4 on the outer and inner sides of each petal layer 3 to block water flow, thus dividing each petal layer 3 into multiple cavities. Each cavity has a gradually decreasing internal pressure depending on its distance from the central tube 1. Raw water flows from the outermost layer along an S-shaped path into the innermost wall closest to the central tube 1, and the water flow thus passes through multiple reverse osmosis membranes 2 from the outside to the inside, thereby achieving multiple filtration effects of the reverse osmosis membranes 2. Therefore, the present invention can achieve the effect of multiple reverse osmosis membrane filtration without increasing the number of reverse osmosis membranes, greatly improving the filtration efficiency of the reverse osmosis membrane device. Meanwhile, since the water flows through the multiple segments of the reverse osmosis membrane that are dusted, the entire reverse osmosis membrane of each petal 3 can be utilized from the outside to the inside. This avoids the situation in general reverse osmosis membrane devices where the reverse osmosis membrane near the outer cylinder is used more while the reverse osmosis membrane near the center tube 1 is used less efficiently. This fundamentally improves the overall utilization rate of the reverse osmosis membrane.

[0042] The above description is merely an illustrative embodiment of the present invention and is not intended to limit the scope of the invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention should fall within the scope of protection of the present invention.

Claims

1. A method for preparing a reverse osmosis membrane, characterized in that, It is equipped with a reverse osmosis membrane, a front end cap, a rear end cap, a central tube, and an outer cylinder; Including the following steps:

1. Cut the reverse osmosis membrane into a specified length and width, the width of which is less than the inner length of the outer cylinder; fold it around the central tube into a petal-shaped structure with petals, each petal rotating around the central tube in one direction and pressing against each other; 2. A first pressing mark and a second pressing mark are marked on the outer surfaces of both sides of the petal, respectively. The first pressing mark of the former petal corresponds to and is attached to the second pressing mark of the latter petal. A third pressing mark and a fourth pressing mark are marked on the inner surfaces of both sides of the petal, respectively. The third pressing mark and the fourth pressing mark are attached to the inner side of the same petal. The third pressing mark and the fourth pressing mark are located on the inner side of the first pressing mark and the second pressing mark towards the central tube.

3. Apply adhesive to each of the first and third pressing marks, press and bond the first pressing marks of each front lobe and the second pressing marks of each rear lobe together in sequence, and press and bond the third and fourth pressing marks on the inner side of each lobe together in sequence.

4. Adhere the two openings on both sides of each of the aforementioned petals together, and adhere the two ends of the reverse osmosis membrane together to form a reverse osmosis membrane column; 5. Place the central tube into the central hole of the reverse osmosis membrane column, and seal the two ends of the central hole of the reverse osmosis membrane column to form a reverse osmosis membrane module.

6. Install the reverse osmosis membrane module into the outer cylinder, install the front end cap at the inlet end, and install the rear end cap at the outlet end.

2. The method for preparing the reverse osmosis membrane as described in claim 1, characterized in that, Following step three, the method further includes inserting a spacer into the first and second lobes cavity formed by the third and fourth pressure marks within the lobes.

3. The method for preparing the reverse osmosis membrane as described in claim 2, characterized in that, Step three is followed by inserting a spacer into the inner first lobe cavity formed after the first and second pressing marks adhere together.

4. The method for preparing the reverse osmosis membrane as described in claim 3, characterized in that, The process after step four also includes inserting a spacer mesh at the interval between the two lobes outside the adhesion points of the first and second pressing marks.

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