CN115155156B

CN115155156B - Flexible filtering soft diaphragm and filtering method

Info

Publication number: CN115155156B
Application number: CN202210866754.XA
Authority: CN
Inventors: 洪晨
Original assignee: Shengshi Weilan Shandong Environmental Technology Co ltd; Suzhou Weihang Environmental Technology Co ltd; University of Science and Technology Beijing USTB
Current assignee: Shengshi Weilan Shandong Environmental Technology Co ltd; Suzhou Weihang Environmental Technology Co ltd; University of Science and Technology Beijing USTB
Priority date: 2022-07-22
Filing date: 2022-07-22
Publication date: 2024-07-26
Anticipated expiration: 2042-07-22
Also published as: CN115155156A

Abstract

The utility model provides a filter membrane, includes first filter layer, water guide layer and second filter layer, and the water guide layer is located between first filter layer and the second filter layer, and wherein, the water guide layer includes a plurality of flexible muscle, and flexible muscle is arranged side by side along first direction interval in proper order. The filter membrane, the gaps between adjacent flexible ribs form a water guide channel. When the filter membrane is used as the filter membrane of the water-containing material, when the water-containing material is subjected to extrusion stress, the water in the water-containing material enters the water guide channel of the water guide layer through the filter layer, so that the water is easily discharged through the water guide channel, and the solid-liquid separation effect is improved.

Description

Flexible filtering soft diaphragm and filtering method

Technical Field

The application relates to a filtering diaphragm, in particular to a flexible filtering soft diaphragm which is used for deep extrusion dehydration of high-water-content materials and belongs to the field of solid-liquid separation.

Background

The solid-liquid separation method is various, including squeezing, centrifuging, etc., and the corresponding solid-liquid separation equipment is also various. Currently, a dewatering mode of stacking and laminating and combining high-pressure filter pressing is increasingly applied. In this dewatering mode, a single or multiple layers of filter cloth are used to separate the layers of aqueous material. The filter cloth is used for filtering moisture and simultaneously serves as a water guide layer for transmitting the filtered moisture to the outside, and is two main functions of the filter cloth.

The process of removing moisture in materials by stacking and laminating dehydration comprises two stages: firstly, separating water from materials, and secondly, guiding the separated water out and discharging. In the dehydration process, along with the increase of the filter pressing pressure, the water in the material can be more extruded out and is separated from the material through the filter cloth, so that more effective solid-liquid separation is realized. But the increase of the press filtration pressure also results in a more compact filter cloth being pressed. Thus, the water guide path formed by the thread gaps of the filter cloth itself and the gaps between the filter cloths is greatly compressed. Instead, water removal becomes increasingly difficult with increasing pressure of the press. The difficult water drainage causes reverse pressure, and reverse blocking water is separated from materials, which is unfavorable for smooth process.

The diaphragm used at present is mainly a hard diaphragm on a plate-and-frame filter press, has a fixed shape, cannot be bent and folded greatly, and cannot meet the requirements of stacking and laminating dehydration processes. Therefore, there is a need to develop new membranes with better filtration performance.

Disclosure of Invention

The application aims to deeply squeeze water-containing materials, improve the solid-liquid separation effect, and especially improve the solid-liquid separation effect of the water-containing materials.

Another object of the present application is to provide a smooth water guide channel, eliminate the above-mentioned reverse pressure which is unfavorable for dehydration, and implement high-efficiency and quick water-guiding-out.

The utility model provides a filter membrane, includes first filter layer, water guide layer and second filter layer, and the water guide layer is located between first filter layer and the second filter layer, and wherein, the water guide layer includes a plurality of flexible muscle, and flexible muscle is arranged side by side along first direction interval in proper order.

The flexible rib can be linear or curved in the length direction. The flexible rib can be deformed and bent under a certain pressure. Has certain ductility.

According to the filter membrane disclosed by the application, gaps between adjacent flexible ribs form water guide channels. When the filter membrane is used as the filter membrane of the water-containing material, when the water-containing material is subjected to extrusion stress, the water in the water-containing material enters the water guide channel of the water guide layer through the filter layer, so that the water is easily discharged through the water guide channel, and the solid-liquid separation effect is improved.

Drawings

FIG. 1 is a schematic view of a layered structure of a filter membrane

FIG. 2 is a schematic view of a water-conducting layer

FIG. 3 is a schematic view of a structure of a flexible rib

FIG. 4 is a schematic view of some of the ways in which the flexible ribs of the water-guiding layer are laid

FIG. 5 is a schematic view showing the moving direction of water in the water guiding layer

FIG. 6 is a schematic view of the overall structure of a filter membrane

FIG. 7 is a schematic illustration of a filter membrane and one manner of laying the aqueous material

FIGS. 8-9 are schematic illustrations of alternative arrangements of filter membranes and aqueous material

FIG. 10 is a schematic diagram of the construction of a filter cylinder with an aqueous material and a filter membrane applied thereto.

Detailed Description

The filtration membrane of the present application is described in further detail below. And do not limit the scope of the application, which is defined by the claims. Certain disclosed specific details provide a thorough understanding of the various disclosed embodiments. However, one skilled in the relevant art will recognize that embodiments can be practiced without one or more of the specific details, with other materials, etc.

In the description and in the claims, the terms "comprising," including, "and" containing "are to be construed as open-ended, meaning" including, but not limited to, unless the context requires otherwise.

Reference in the specification to "an embodiment," "one embodiment," "another embodiment," or "certain embodiments," etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, it is not necessary for an "embodiment," "one embodiment," "another embodiment," or "certain embodiments" to refer to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. The various features disclosed in the specification may be replaced by alternative features serving the same, equivalent or similar purpose. Thus, unless expressly stated otherwise, the disclosed features are merely general examples of equivalent or similar features.

The terms of directions such as up, down, left, right, front and rear in the present document are established based on the positional relationship shown in the drawings. The drawings are different, and the corresponding positional relationship may be changed, so that the scope of protection cannot be understood.

The middle layer of the filtering diaphragm is formed by paving flexible ribs, has certain compression resistance and flexibility, and can be bent back and forth when the filtering diaphragm and the water-containing materials are paved. The flexible ribs have rigid compression limit, and in the process of extrusion dehydration under external force, the skeleton structure can be kept between the flexible ribs, so that the smoothness of the water guide channel can be ensured. May also be referred to as a flexible filtration soft membrane. Materials capable of the above functions can be used as the flexible ribs.

The application relates to a filter membrane, which comprises a first filter layer, a water guide layer and a second filter layer, wherein the water guide layer is positioned between the first filter layer and the second filter layer, and comprises a plurality of flexible ribs which are arranged in parallel at intervals along a first direction.

The flexible rib has a fixed shape under the condition of no stress, and can be linear or curved in the length direction. The flexible rib can deform and bend under certain pressure and has certain ductility.

At least one layer of flexible ribs is paved on the water guide layer to form a water guide channel.

The cross section of the flexible rib can be round, elliptic or square, and can also be in other irregular shapes.

In certain embodiments, the flexible ribs are circular, quasi-circular in cross-section.

The flexible ribs are transversely and sequentially arranged between the first filter layer and the second filter layer at intervals along the first direction. Preferably, the height of the flexible ribs is 0.5-2 mm in a direction perpendicular to the first/second filter layers.

The term "transverse" as used herein means that the flexible ribs are parallel to the first and second filter layers.

The height of flexible muscle in the direction of perpendicular to filter layer, both to guarantee to extrude smooth and easy, the quick drainage through the water guide channel of water, simultaneously, avoid at extrusion process, first filter layer or second filter layer are by transition extension and lead to first filter layer or second filter layer to damage.

In some embodiments, adjacent flexible ribs are spaced apart a distance of 2-20mm.

In some embodiments, the water guiding layer between the first filtering layer and the second filtering layer is at least paved with two layers of flexible ribs, the first layer of flexible ribs and the second layer of flexible ribs are arranged between the first filtering layer and the second filtering layer in parallel along a first direction interval in a transverse direction, and the flexible ribs of the second layer of flexible ribs are arranged between the first filtering layer and the second filtering layer in parallel along a second direction interval in a transverse direction, wherein the first direction intersects with the second direction.

The water guide layer can also be provided with more than two layers of flexible ribs, and the arrangement directions of the flexible ribs of two adjacent layers are at a certain angle. Preferably, the arrangement direction of the flexible ribs of two adjacent layers is 20-90 degrees.

Adjacent flexible ribs of each layer form water guide channels. The filtering diaphragm of laying multilayer flexible muscle forms the water guide passageway in the multi-direction, simultaneously, the water guide passageway intercommunication each other on different flexible muscle layers, and moisture also can get into other flexible muscle layers through the gap, discharges through the water guide passageway on other flexible muscle layers, has improved the discharge efficiency of moisture.

In some embodiments, the flexible ribs are curved in the longitudinal direction in the same plane. Thus, when the water guiding layer is laid, the flexible ribs take a curved shape on the same plane parallel to the first filter layer or the second filter layer.

In other words, the planes of the layers of the multi-layer flexible rib are parallel to each other and are not bent towards the planes of the other flexible rib layers.

The flexible rib can be made of any material meeting certain performance, has good bending performance, and has higher mechanical strength and compression resistance.

In some embodiments, the flexible ribs are made of strands of fiber filaments. The fiber yarn comprises one or two of glass fiber and metal fiber.

The filter membrane with the multi-layer flexible ribs is used for filtering multi-layer water-containing materials, and has more remarkable filtering effect. Between the multilayer water-containing materials of laying, filtration membrane can provide multidirectional water guide passageway between the adjacent water-containing material layer, and the efficient is discharged moisture, improves solid-liquid separation efficiency.

The first filter layer and the second filter layer can be filter cloth with the same water permeability. The filter cloth with different water permeability can also be selected, namely the water permeability of the first filter layer is lower than that of the second filter layer.

"Water permeability" as used herein refers to the ability of liquid water to permeate from one side of the first/second filter layer to the other.

The first filter layer or the second filter layer is filter cloth. The material is terylene, polypropylene, nylon and vinylon, and is woven by one or more of the terylene, the polypropylene, the nylon and the vinylon.

In certain embodiments, the water permeability of the first filter layer of the filter membrane is lower than the water permeability of the second filter layer, the first filter layer being configured to be in direct contact with the aqueous material.

The second filter layer has high water permeability, and is a cloth material with good water permeability, such as: the material comprises cotton cloth, flax, artificial fiber, synthetic fiber, etc. The highly permeable substrate layer is easily permeable to water and can protect the flexible water-guiding layer. The water guide layer is paved with more than two layers of flexible ribs, the layers are overlapped to form a net structure, the damage is easy to hook, and the entering foreign matters are not easy to discharge to cause blockage. Because the protection of the stratum basale of high water permeability, the foreign matter is difficult for getting into the water guide layer, has both prevented the damage of water guide layer structure, has still guaranteed the smoothness and smoothness of water guide channel.

The layers of the filter membrane can be combined by the method disclosed in the prior art, and can be combined in a sewing and bonding mode. Such as: the flexible ribs of each layer of the water guide layer can be combined in a bonding mode, the water guide layer is combined with the first filter layer/the second filter layer made of chemical fiber materials in a bonding mode, and the high-permeability filter layer such as cotton cloth and other materials can be connected with other layers of the filter membrane in a sewing mode. The manner of connection between the layers of the filter membrane is not limited as long as the filter membrane with the water guide channel of the present application can be formed.

The whole form of the filter membrane of the application: square, round, polygonal or long-web.

The filter membrane comprises: an edge portion, a diaphragm portion; the edge part is composed of a first filter layer and a second filter layer only; the diaphragm part is provided with a water guide layer between the first filter layer and the second filter layer.

The whole filter membrane may consist of the edge portion primary membrane portion or may consist of only the membrane portion.

On the other hand, the solid-liquid separation method using the filter membrane of the present application comprises: laying a plurality of layers of filter diaphragms in the same direction; the water-containing material is arranged between the two layers of filtering diaphragms;

And extruding the paved multi-layer filtering diaphragms and the water-containing materials to discharge the water and realize solid-liquid separation.

In certain embodiments, a solid-liquid separation process comprises: laying a plurality of layers of filter membranes in the same direction, wherein the water permeability of a first filter layer of the filter membrane is lower than that of a second filter layer;

The water-containing material is arranged between the two layers of filter membranes, and each layer of water-containing material is in direct contact with the first filter layer of the two layers of filter membranes;

When the existing filter cloth is adopted for solid-liquid separation of multi-layer water-containing materials, the water content of the water-containing materials of the middle layer is generally inconvenient to discharge, and when the water-containing materials of the surface layer (such as water-containing sludge) are dehydrated and form a hard layer in deep extrusion of the later stage, the water content of the sludge positioned in the middle layer is inconvenient to discharge, so that the solid-liquid separation effect is affected. In the solid-liquid separation method, a plurality of layers of water-containing materials are paved in the vertical direction, and each layer of water-containing material is in direct contact with the first filter layer of the two layers of filter membranes. When laying the multilayer water-containing material, be located the water-containing material layer in intermediate level and need set up two-layer filtration membrane between the layer, can provide more water guide space and water guide passageway for every layer of water-containing material.

The filtration membrane and the filtration method of the present application are described in further detail below with reference to the specific drawings.

Referring to fig. 1, the filter membrane includes a first filter layer 1, a water-guiding layer 2, and a second filter layer 3, the water-guiding layer 2 being disposed between the first filter layer 1 and the second filter layer 3. The first filter layer 1 and the second filter layer 3 may have filter cloths with the same water permeability, i.e., filter cloths of the same material (fig. 1A). Or the water permeability of the first filter layer 1 is lower than that of the second filter layer 3' (see fig. 1B). The second filter layer 3 has good water permeability and plays a role in protecting the water guide layer.

The water guiding layer 2 is formed by arranging a plurality of flexible ribs 21. As shown in fig. 1-3, in one embodiment, the flexible ribs 21 are cylindrical in configuration. The flexible ribs 21 are paved on a plane parallel to the first filtering layer and the second filtering layer, the flexible ribs 21 are mutually parallel and arranged at intervals on the same plane, and water guide channels are formed at intervals between adjacent flexible ribs 21 on the same plane. The flexible ribs 21 may be provided in multiple layers, as shown in fig. 2 or 4, and the water guiding layer may be provided with two, three or four layers, i.e. the flexible ribs 21 are laid on two, three or four planes. The adjacent two layers of flexible ribs 21 are arranged in an intersecting manner, as shown in fig. 4, and the included angle between the adjacent two layers of flexible ribs 21 can be set to be 20-90 degrees.

In another embodiment, the flexible rib 21 has a curved shape in the longitudinal direction. The bending direction is on the same horizontal plane, and when the bending direction is arranged between the first filtering layer and the second filtering layer, the bending direction is in the same plane, and the bending direction is not in other directions.

The filter membrane with the structure is used in a solid-liquid separation system, and an aqueous material (such as aqueous sludge) is placed on the filter membrane. During the extrusion process, water enters the water guiding layer 2 through the first or second filter layer, and water in the water guiding layer 2 is discharged through the multi-directional water guiding channels formed by the flexible ribs 21, referring to fig. 5.

Integral form of the filtration membrane: square, round, polygonal or long-web shaped as shown in fig. 6. The filter membrane comprises: an edge portion 61, a diaphragm portion 62; the rim portion 61 is constituted by only the first filter layer 1 and the second filter layer (3, 3'); the membrane portion 62 is provided with a water-guiding layer 2 between the first and second filter layers. The whole piece of the filter membrane may consist of the edge portion 61 and the membrane portion 62, or may consist of only the membrane portion 62.

The water permeability of the first filter layer 1 of the filter membrane is lower than the water permeability of the second filter layer 3', and the first filter layer 1 is directly contacted with the water-containing material in the use of the filter membrane in the solid-liquid separation process.

There are various methods for laying the filter membrane in the solid-liquid separation process, as described below.

The filter cylinder is matched with the filter membrane to dehydrate the materials.

As shown in fig. 10, the filter cylinder comprises a cylinder body 7 and a movable bottom plate 71 positioned in the cylinder body, wherein the cylinder body 1 is of a hollow cube structure or a hollow cylinder structure, and water outlet holes 72 are formed in the side surfaces of the cylinder body 1; the top of the cylinder body is open, and the movable bottom plate 71 is matched with the cross section of the inner cavity of the cylinder body 7 and can move up and down along the cylinder body 1. To show the movable floor 71 and the laid out aqueous material and the filter membrane, it is shown separately from the cylinder 7.

Typically, a square, polygonal or circular filter membrane similar in shape to the mouth of the jar is used, the movable bottom plate 71 is raised to the upper end of the mouth of the jar, and the filter membrane-water-containing material-filter membrane-layer is laid on the movable bottom plate 71 to form a membrane material structure to be filtered. Simultaneously, the movable bottom plate gradually moves downwards along with the laying process, so that the material structure of the diaphragm to be filtered is lower than or flush with the cylinder opening.

The first method for laying the filtering diaphragm and the water-containing material comprises the following steps: the long-width filter membrane is used, and the cylinder opening of the filter cylinder is rectangular. One end of the filter membrane is paved on the movable bottom plate 71, after the filter membrane is paved with a layer of water-containing material, the filter membrane is bent once and covered on the water-containing material, then the filter membrane is paved with a layer of water-containing material again, and the filter membrane is bent once again, so that the whole paving operation is completed; (a state where a layer of a separator is formed and a layer of a material is formed).

In the first laying method, the water permeability of the first and second filter layers of the preferred filter membrane is substantially uniform.

During extrusion, referring to fig. 5 and 7, the extruded moisture in the aqueous material may be discharged toward the plurality of water guide channels of the water guide layer in the vertical up and down direction and in the horizontal direction. On the other hand, the water of the multi-layer water-containing material can smoothly move upwards or downwards to the water guide layers of other filtering diaphragms, and the water guide channels in the horizontal direction of one layer need to be led out too much water, so that the water guide channels flowing upwards or downwards to other filtering diaphragms can be quickly drained away. Referring to fig. 10, the filtering membrane and the water-containing material are laid in the cylinder 7, and even if the water-containing material is located in the middle of the cylinder, the water can move around the cylinder 7 through the water guide channels of different water guide layers, and then is discharged from the water outlet holes on the side wall of the cylinder.

The second method for laying the filter membrane and the water-containing materials uses a long-width filter membrane, and the cylinder opening of the filter cylinder is rectangular. One end of the filter membrane is paved on the movable bottom plate 71, after a layer of water-containing material is paved on the filter membrane, the filter membrane is bent once to cover the water-containing material, and then is bent once again to cover two layers of filter membranes on the water-containing material, and then a layer of water-containing material is paved on the filter membrane, and then is bent twice, so that the filter membrane is reciprocated until all the paving operation is completed; (a state where two layers of the separator and one layer of the material are formed).

In the second laying method, the first filter layer 1 of the preferred filter membrane has a lower water permeability than the second filter layer 3'. The first filter layer 1 is in direct contact with the aqueous material.

Referring to fig. 7 and 10, in the vertical direction of the cylinder 7, a filter membrane and an aqueous material are layered, and the upper and lower surfaces of each layer of the aqueous material are directly contacted with the first filter layer 1. Two layers of filter membranes are arranged between two adjacent layers of water-containing materials, and the second filter layers 3' of the two layers of filter membranes are contacted. In the case of laying multiple layers of aqueous material, the water flow is not hindered between two adjacent layers of filter membrane due to the high water permeability of the second filter layer 3', and more space and more water guiding channels are provided between the layers of aqueous material in the middle layer. Further, the dewatering efficiency is further improved.

Other ways of laying the filter membrane and the aqueous material than the two methods described above are possible. For example, as shown in fig. 8 and 9, the filtering membrane can be cut into a plurality of independent membranes larger than the area of the opening of the cylinder body without bending, the water-containing material is paved between every two layers of filtering membranes, and the periphery of the two layers of filtering membranes can wrap the water-containing material.

No matter what way is adopted to lay the water-containing material and the filtering diaphragm, when in extrusion dehydration, the extrusion pressing plate with the same size as the inner edge of the cylinder opening enters from the cylinder opening and moves downwards to carry out extrusion dehydration. The width of the filtering diaphragm is slightly larger than the side length of the inner cavity of the cylinder body, during the dehydration process, the edge of the filtering diaphragm entering the cylinder body is turned upwards due to the extrusion effect, and the turned filtering diaphragm fills the edge gap to form a seal due to the fact that the filtering diaphragm and materials in the filtering diaphragm are accumulated layer by layer; the water-containing material is sealed in the filter membrane, and only water can pass through the filter pores and the water guide channels of the filter membrane; the extruded water flows out of the cylinder body through the water outlet holes on the side surface of the cylinder body. Under the action of extrusion filter pressing, the flexible water guide layer still keeps relatively large water seepage space and water guide channel, greatly increases the speed of water discharge, can more effectively reduce the water content of materials, and prevents the conditions of unsmooth water discharge and central water backlog caused by the fact that no water seepage space exists and the water guide channel is blocked by extrusion when only filter cloth is used.

Claims

1. A method for solid-liquid separation of aqueous sludge, comprising: laying a plurality of layers of filter membranes in the same direction, wherein the water permeability of a second filter layer of the filter membrane is higher than that of the first filter layer;

The water-containing sludge is arranged between the two layers of filtering diaphragms, and each layer of water-containing sludge is in direct contact with the first filtering layer of the two layers of filtering diaphragms;

Extruding the laid multi-layer filtering diaphragms and the water-containing sludge to discharge water and realize solid-liquid separation;

The filter membrane comprises a first filter layer, a water guide layer and a second filter layer, wherein the water guide layer is positioned between the first filter layer and the second filter layer, and comprises a plurality of flexible ribs which are in a bending shape in the length direction;

The water guide layer is at least paved with a first layer of flexible ribs and a second layer of flexible ribs to form a water guide channel, the flexible ribs of the first layer of flexible ribs are arranged between the first filter layer and the second filter layer at intervals along a first direction in the transverse direction in sequence, and the flexible ribs of the second layer of flexible ribs are arranged between the first filter layer and the second filter layer at intervals along a second direction in the transverse direction in sequence, wherein the first direction is intersected with the second direction;

The arrangement direction of the flexible ribs of two adjacent layers is 20-90 degrees.

2. The method according to claim 1, wherein the height of the flexible ribs is 0.5-2 mm in a direction perpendicular to the first/second filter layers.

3. A method according to claim 2, wherein adjacent flexible ribs are spaced apart a distance of 2-20mm.

4. A method according to any one of claims 1-3, wherein the flexible ribs are curved in the longitudinal direction in the same plane; when the water guide layer is paved, the flexible ribs are in a bending shape on the same plane parallel to the first filter layer or the second filter layer.

5. A method according to any one of claims 1-3, characterized in that the flexible ribs are made of strands of fibre filaments.

6. The method of claim 5, wherein the fiber filaments comprise one or both of glass fibers and metal fibers.

7. A method according to any one of claims 1-3, wherein the whole form of the filter membrane: making into square, round, polygonal or long-width shape;

The filter membrane comprises: an edge portion, a diaphragm portion; the edge part is composed of a first filter layer and a second filter layer only; the diaphragm part is provided with a water guide layer between the first filter layer and the second filter layer;

Or the filter membrane is only composed of a membrane part, and the membrane part is a water guide layer arranged between the first filter layer and the second filter layer.