Method and system for filtering a solid-liquid two-phase flow

Abstract

This invention discloses a filtration method and system for solid-liquid two-phase flow. The method includes: S100, employing a filter frame with an opening at the top, the filter frame having a bottom filter section and a side filter section, the side filter section surrounding the bottom filter section; S200, a two-phase flow is introduced into the filter frame through the corresponding opening of a two-phase flow input device, and during the filtration process, a filter cake layer is formed in the filter cake accumulation area above the bottom filter section and within the side filter section, the introduced two-phase flow directly impacts the filter cake layer for filtration; and S300, when the thickness of the filter cake layer on the bottom filter section increases to the point where the filtration process cannot be completed smoothly, the two-phase flow continues to be filtered through the side filter section on the top side of the filter cake layer. The solid-liquid two-phase flow filtration method and system of this invention adopts the concept of filter layer disturbance filtration. By impacting the filter cake layer with the two-phase flow, the filter cake layer is continuously disturbed during the filtration process, resulting in a smaller filter cake layer density than that formed in a typical filtration process, thereby improving filtration efficiency and filtration quality.

Description

Technical Field

[0001] This invention relates to the field of filtration technology, and more specifically, to a filtration method and system for solid-liquid two-phase flow. Background Technology

[0002] In solid-liquid two-phase flow, a filter medium is used to prevent the solid phase from passing through while allowing the fluid to flow, thus separating the solid from the liquid. This method is called filtration. Filtration can trap particles larger than the pore size of the filter medium and the diameter of the filter cake channels. During filtration, the filter medium and the filter cake are responsible for intercepting the particles, and the filter medium also supports the filter cake. Typically, the filtrate must pass through the filter cake layer to be discharged during filtration. As the filter cake layer gradually accumulates, the discharge channel becomes longer and narrower, increasing filtration resistance and reducing filtration quality, resulting in the retention of many desired particles. Therefore, maintaining the initial state of the filter screen is crucial for improving filtration efficiency. Since in traditional filtration processes, the filter layer gradually increases, maintaining the original state of the filter screen throughout the entire filtration process is virtually impossible. Summary of the Invention

[0003] The purpose of this invention is to provide a filtration method and system for solid-liquid two-phase flow, which adopts a simple structure and process, and agitates the filter cake layer during the filtration process to reduce the resistance to the discharge of filtrate, thereby improving filtration efficiency and filtration quality.

[0004] To achieve the above objectives, the solid-liquid two-phase flow filtration method of the present invention includes the following steps:

[0005] S100 adopts a filter frame with an opening at the top, and the filter frame has a bottom filter section and a side filter section, with the side filter section arranged around the bottom filter section.

[0006] S200, the two-phase flow input device introduces two-phase flow through the corresponding opening. During the filtration of the two-phase flow, a filter cake layer is formed in the filter cake accumulation area above the bottom filter screen and inside the side filter screen. The introduced two-phase flow directly impacts the filter cake layer for filtration, thereby reducing the resistance to the discharge of filtrate and avoiding the retention of smaller solid particles by the already generated filter cake.

[0007] S300: When the thickness of the filter cake layer on the bottom filter screen accumulates, causing excessive resistance to the flow of the filtrate, the side filter screen can continue the filtration process.

[0008] Because a large space can be set inside the filter frame to store solids, the time for discharging solids can be greatly extended, which is beneficial for the continuous operation of the filtration process.

[0009] In one embodiment of the above-described filtration method for solid-liquid two-phase flow, the method further includes the following steps:

[0010] S400, the filter frame is immersed in the circulating water tank for filter device regeneration. When the upper plane of the filter cake layer is lower than the liquid level of the circulating water tank, water flows in and washes off the sediment on the side filter screen and deposits it on the filter cake layer.

[0011] Furthermore, the liquid level in the circulating water tank can submerge the filter frame, allowing the entire side filter section to be impacted.

[0012] In one embodiment of the above-described filtration method for solid-liquid two-phase flow, the method further includes the following steps:

[0013] S500: Move the filter frame to the top of the sludge tank, flip the filter frame so that the opening aligns with the sludge tank, and most of the filter cake inside the filter frame falls into the sludge tank.

[0014] In one embodiment of the above-described solid-liquid two-phase flow filtration method, step S500 is performed after step S400.

[0015] In one embodiment of the above-described filtration method for solid-liquid two-phase flow, the method further includes the following steps:

[0016] The S600 uses high-pressure water or high-pressure air to back-purge the bottom and side filter sections.

[0017] The solid-liquid two-phase flow filtration system of the present invention includes a filter frame and a two-phase flow input device. The top of the filter frame has an opening and includes a bottom filter screen portion and a side filter screen portion. The side filter screen portion is disposed around the bottom filter screen portion, and a filter cake accumulation area for accommodating the filter cake layer is formed above the bottom filter screen portion and inside the side filter screen portion. The two-phase flow input device is located above the filter frame and is disposed corresponding to the opening.

[0018] In one embodiment of the above-described solid-liquid two-phase flow filtration system, the bottom filter screen is horizontally arranged, the side filter screen is vertically arranged, and the top of the filter frame is open.

[0019] In one embodiment of the above-mentioned solid-liquid two-phase flow filtration system, a moving mechanism and a circulating water tank are also included. During filtration, the filter frame is located above the circulating water tank, and the moving mechanism allows the filter frame to be immersed in the circulating water tank.

[0020] In one embodiment of the above-mentioned solid-liquid two-phase flow filtration system, a filter residue unloading mechanism is further included. The filter residue unloading mechanism includes a flipping mechanism and a residue pool. The moving mechanism drives the filter frame to move above the residue pool. The flipping mechanism flips the filter frame so that the opening corresponds to the residue pool, and most of the solid phase material can reliably fall into the residue pool by its own weight.

[0021] In one embodiment of the above-mentioned solid-liquid two-phase flow filtration system, a backflushing mechanism for introducing high-pressure air or high-pressure water is also included. The backflushing mechanism is provided corresponding to the bottom filter screen and / or the side filter screen to further discharge solid matter that may remain on the filter screen.

[0022] The beneficial effects of the present invention are that the solid-liquid two-phase flow filtration method and system of the present invention adopt the idea of ​​filter layer disturbance filtration. By impacting the two-phase flow, the filter cake layer is continuously disturbed during the filtration process, and the filter screen can be directly exposed to the two-phase flow. Even if the density of the generated filter cake layer is less than that of the filter cake layer formed in the usual filtration process, the filtration resistance will be reduced, and the filtration efficiency and filtration quality will be improved.

[0023] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention. Attached Figure Description

[0024] Figure 1 This is a simplified schematic diagram of the solid-liquid two-phase flow filtration system of the present invention.

[0025] Figure 2 This is a simplified diagram of the regeneration process of the solid-liquid two-phase flow filtration system of the present invention.

[0026] Figure 3 This is a step diagram of the solid-liquid two-phase flow filtration method of the present invention;

[0027] Figure 4 This is a structural diagram (filtration state) of an embodiment of the solid-liquid two-phase flow filtration system of the present invention.

[0028] Figure 5 This is a structural diagram (unloading state) of an embodiment of the solid-liquid two-phase flow filtration system of the present invention.

[0029] Among them, the attached figures are labeled

[0030] 100: Filter frame

[0031] 100a: Open

[0032] 110: Bottom filter section

[0033] 120: Side filter section

[0034] 130: Filter cake storage area

[0035] 200: Two-phase flow input device

[0036] 300: Filter cake layer

[0037] 400: Circulating water tank

[0038] 600: Mobile Agency

[0039] 610: Walking mechanism

[0040] 611: Walking Cart

[0041] 612: Walking Track

[0042] 620: Lifting mechanism

[0043] 700: Tilting Mechanism

[0044] 800: Support frame Detailed Implementation

[0045] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments to further understand the purpose, solution and effect of the present invention, but it is not intended to limit the scope of protection of the appended claims.

[0046] like Figure 1 and Figure 3 As shown, the solid-liquid two-phase flow filtration method of the present invention includes the following steps:

[0047] S100 adopts a filter frame 100 with an opening 100a at the top, and the filter frame 100 has a bottom filter part 110 and a side filter part 120, with the side filter part 120 arranged around the bottom filter part 110.

[0048] S200, the two-phase flow input device 200 introduces a two-phase flow through the opening 100a at the top of the filter frame 100. During the two-phase flow filtration process, a filter cake layer 300 is formed in the filter cake accumulation area 130 above the bottom filter screen section 110 and within the side filter screen section 120. During the filtration process, the introduced two-phase flow directly impacts the filter cake layer 300, and the filtration process continues while the filter cake layer 300 is disturbed.

[0049] S300, the filter cake layer 300 is mainly stored above the bottom filter screen section 110. When the thickness of the bottom filter cake layer 300 increases and the flow resistance increases, filtration can continue through the side filter screen section 120.

[0050] In detail, in the filtration section through which the solid-liquid two-phase flow passes, filter screens are arranged on both the bottom and sides of the filter frame 100. The filter cake layer 300 formed during the filtration process first accumulates on the bottom filter screen portion 110. After the solid-liquid two-phase flow enters the filter cake accumulation area 130, it directly impacts the filter cake layer 300, which can prevent the filter cake layer 300 from becoming dense, giving the filter cake layer 300 good flow capacity and maintaining filtration capacity for a longer period of time.

[0051] When excessive filter layer buildup in the bottom filter section 110 affects liquid phase discharge, the filtration process can continue through the side filter section 120 above the filter cake layer 300. Since the side filter section 120 is vertically arranged and the two-phase flow direction is from top to bottom, it acts as a flushing agent on the side filter section 120. Therefore, filter cake is less likely to accumulate in this section, and solids remain on the horizontal filter cake layer 300 located within the filter cake accumulation area 130.

[0052] Under this filtration concept, the filter cake layer 300 is constantly disturbed during the filtration process, which can better maintain the flow capacity of the filter layer. The allowable thickness of the filter cake layer 300 can also be relatively increased until the filter cake layer 300 becomes too thick and its impact effect is limited, at which point the side filter screen section 120 can continue to carry out the filtration process.

[0053] Since the filtration effect is limited by the pore size of the filter screen, disturbance to the filter cake layer 300 will not affect the filtration effect. At the same time, it can reduce the retention of smaller solid particles by the filter layer and improve the filtration effect.

[0054] When the filter cake layer 300 accumulates to a certain thickness in the side filter section 120, affecting the filtration capacity, a simple online method can be used to regenerate the filter section. For example... Figure 2 and Figure 3 As shown, the solid-liquid two-phase flow filtration method of the present invention further includes the following steps:

[0055] S400, the filter frame 100 is immersed in the circulating water tank 400 to regenerate the filter device. For example, when the upper plane of the filter cake layer 300 is lower than the liquid level of the circulating water tank 400, water flows in and washes off the sediment on the side filter screen 120 and deposits it on the filter cake layer 300.

[0056] The filter frame 100 is immersed in the circulating water tank 400. As long as the liquid level in the circulating water tank 400 is higher than the filter cake layer 300, the water flow flowing into the filter frame 100 from the outside will wash down the sediment on the side filter screen 120 and redeposit it in the horizontal filter cake layer 300. The flowing water will also have a certain impact on the filter cake layer 300, which will loosen the filter cake layer 300 to a certain extent and improve its flow capacity. Then the filter frame 100 is removed from the circulating water tank 400, and the filtration process can continue until the entire interior of the filter frame 100 is filled with solid sediment. Because the filter frame 100 has a large internal space that can hold a large amount of solid sediment, the filtration process can be continued for a longer period of time before the filter cake is removed.

[0057] Since the regeneration process does not affect the filtration process, the regeneration step can be scheduled at any time to keep the filtration process running smoothly and improve filtration efficiency.

[0058] Moreover, the filter cake of this structure is always present in the filter frame 100. As long as the filter frame 100 is moved to the place where the filter cake is collected, the filter cake can be poured out, which saves the difficulty of secondary transfer of filter residue in the conventional filtration process.

[0059] If the filtration capacity of the filter frame 100 fails to meet requirements after one or more regenerations, a slag discharge process is necessary. The solid-liquid two-phase flow filtration method of the present invention further includes the following steps:

[0060] S500, move the filter frame 100 onto the sludge tank (not shown in the figure), flip the filter frame 100 so that the opening 100a corresponds to the sludge tank, and the filter cake layer 300 inside the filter frame 100 can fall into the sludge tank.

[0061] Furthermore, it also includes the following steps:

[0062] S600 uses high-pressure water or high-pressure air to back-purge the bottom filter screen 110 and side filter screen 120 of the filter frame 100 to thoroughly remove filter residue from the filter frame 100.

[0063] In summary, the filtration concept proposed by the solid-liquid two-phase flow filtration method of the present invention is to disturb the filter cake layer 300 during the filtration process to avoid the impact of solid deposition on the filtration process. The core of this technology is to make the two-phase flow continuously impact the filter cake layer 300 during the filtration process, so that the filtration process can continue in the state of the filter cake layer 300 being disturbed.

[0064] The filter screen structure proposed in this invention, which allows for side discharge of filtrate, enables the filtrate to be discharged through the side even when the flow at the bottom is obstructed. This extends the filtration interval, improves filtration efficiency, and reduces the time cost caused by frequent filter cake removal.

[0065] This invention also proposes a filtration system for solid-liquid two-phase flow, combined with Figure 1 , Figure 2 as well as Figure 4 , Figure 5 As shown, the filter includes a filter frame 100 and a two-phase flow input device 200. The top of the filter frame 100 has an opening 100a and includes a bottom filter section 110 and a side filter section 120. The side filter section 120 is disposed around the bottom filter section 110, and a filter cake storage area 130 for accommodating the filter cake layer 300 is formed above the bottom filter section 110 and inside the side filter section 120. The two-phase flow input device 200 is located above the filter frame 100 and is disposed corresponding to the opening 100a.

[0066] In one embodiment of the present invention, the bottom filter section 110 is horizontally arranged, the side filter section 120 is vertically arranged, and the filter frame 100 is a cube shape with an open top. Of course, in other embodiments, the filter frame 100 may also be a cuboid or cylindrical shape with an open top, etc., and the present invention is not limited thereto.

[0067] Furthermore, the solid-liquid two-phase flow filtration system of the present invention also includes a circulating water tank 400 and a moving mechanism 600, wherein the moving mechanism 600 includes, for example, a walking mechanism 610 and a lifting mechanism 620, and during the filtration process, the filter frame 100 is located above the circulating water tank 400.

[0068] The walking mechanism 610, for example, drives the filter frame 100 to move on the walking track 612 via the walking trolley 611, and the lifting mechanism 620 drives the filter frame 100 to rise and fall so as to immerse it in the circulating water tank 400 or remove it from the circulating water tank 400, thereby completing the regeneration of part of the filter screen.

[0069] The solid-liquid two-phase flow filtration system of the present invention further includes a slag pool and a flipping mechanism 700. The flipping mechanism 700 flips the filter frame 100 so that the opening 100a corresponds to the slag pool, and pours out the filter slag in the filter frame 100.

[0070] Furthermore, the solid-liquid two-phase flow filtration system of the present invention also includes a backflushing mechanism for introducing high-pressure air or high-pressure water. The backflushing mechanism is provided corresponding to the bottom filter screen 110 and / or the side filter screen 120, and removes the residual filter residue by backflushing after the slag is poured out.

[0071] The solid-liquid two-phase flow filtration system of the present invention further includes a support frame 800, the filter frame 100 is connected to the lifting mechanism 620 through the support frame 800, the flipping mechanism 700 is supported on the lifting mechanism 620, the lifting mechanism 620 is connected to the traveling trolley 611, and the traveling trolley 611 drives the filter frame 100 to travel on the traveling track 612 through the lifting mechanism 620 and the support frame 800.

[0072] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A filtration method for solid-liquid two-phase flow, characterized in that, Includes the following steps: S100 adopts a filter frame with an opening at the top, and the filter frame has a bottom filter section and a side filter section, with the side filter section arranged around the bottom filter section; S200, the two-phase flow input device is connected to the corresponding opening to allow two-phase flow to pass through. During the two-phase flow filtration process, a filter cake layer is formed in the filter cake accumulation area above the bottom filter screen and inside the side filter screen. The introduced two-phase flow directly impacts the filter cake layer for filtration. The filter cake layer is constantly disturbed during the filtration process. S300, when the thickness of the filter cake layer on the bottom filter screen increases to the point that the filtration process cannot be completed smoothly, the two-phase flow continues to be filtered through the side filter screen on the top side of the filter cake layer; S400, the filter frame is immersed in the circulating water tank for filter device regeneration. When the upper plane of the filter cake layer is lower than the liquid level of the circulating water tank, water flows in to wash off the sediment on the side filter screen and deposit it on the filter cake layer. Then the filter frame is lifted out of the circulating water tank, and the filtration process can continue. The regeneration step of immersing the filter frame in the circulating water tank for filter device regeneration can be arranged at any time to keep the filtration process unobstructed until the entire interior of the filter frame is filled with solid phase sediment.

2. The filtration method for solid-liquid two-phase flow according to claim 1, characterized in that, It also includes the following steps: S500: Move the filter frame to the top of the sludge tank, flip the filter frame so that the opening aligns with the sludge tank, and the filter cake layer inside the filter frame falls into the sludge tank.

3. The filtration method for solid-liquid two-phase flow according to claim 2, characterized in that, Step S500 is performed after step S400.

4. The filtration method for solid-liquid two-phase flow according to claim 2, characterized in that, It also includes the following steps: The S600 uses high-pressure water or high-pressure air to back-purge the bottom and side filter sections.

5. A filtration system for solid-liquid two-phase flow, employing the filtration method for solid-liquid two-phase flow as described in any one of claims 1 to 4, comprising a filter frame and a two-phase flow input device, characterized in that, The top of the filter frame has an opening and includes a bottom filter section and a side filter section. The side filter section is arranged around the bottom filter section, and a filter cake accumulation area for accommodating the filter cake layer is formed above the bottom filter section and inside the side filter section. The two-phase flow input device is located above the filter frame and is arranged corresponding to the opening. The solid-liquid two-phase flow filtration system further includes a moving mechanism and a circulating water tank. The moving mechanism drives the filter frame to move until the filter frame is immersed in the circulating water tank. The moving mechanism includes a walking mechanism, a lifting mechanism, a traveling trolley, and a traveling track. During the filtration process, the filter frame is located above the circulating water tank. The walking mechanism drives the filter frame to move on the traveling track via the traveling trolley. The lifting mechanism lifts and lowers the filter frame to immerse it in the circulating water tank or remove it from the circulating water tank, thus completing the regeneration of part of the filter screen.

6. The filtration system for solid-liquid two-phase flow according to claim 5, characterized in that, The bottom filter section is horizontally arranged, the side filter section is vertically arranged, and the filter frame is a rectangle with an opening at the top.

7. The filtration system for solid-liquid two-phase flow according to claim 5, characterized in that, It also includes a filter residue unloading mechanism, which includes a flipping mechanism and a residue pool. The moving mechanism drives the filter frame to move above the residue pool, and the flipping mechanism flips the filter frame so that the opening corresponds to the residue pool.

8. The filtration system for solid-liquid two-phase flow according to claim 7, characterized in that, It also includes a backflushing mechanism for supplying high-pressure air or high-pressure water, the backflushing mechanism being provided corresponding to the bottom filter section and / or the side filter section.

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