Dehydration system of solid-liquid dispersion system

Abstract

The utility model provides a dehydration system of a solid-liquid dispersion system. The system comprises a concentration filter and a pressure settling tank, a thin liquid inlet of the concentration filter is connected with a thin liquid outlet of the pressure settling tank through a pressure pump, and a discharge port of the concentration filter is connected with a concentrated liquid inlet in the lower section of the pressure settling tank through a regulating valve. The concentration filter comprises a closed shell and a multi-tube filter element arranged at the middle section position of the closed shell, high-pressure thin liquid flows into a corresponding filter element tube at a preset speed, part of liquid transversely permeates into a clear liquid cavity through a permeation hole, and concentrated liquid flows to a concentrated liquid conical hopper from an outlet hole in a lower tube plate. The pressure settling tank is vertically arranged and comprises a closed tank shell and a driving mechanism. A cone bottom rake, matched with the conical space of the settling cone, of the driving mechanism stirs a solid-liquid dispersion system in the settling cone, so that liquid in the solid-liquid dispersion system rises into a cylindrical thin liquid cavity to form upper-layer thin liquid, and the upper-layer thin liquid is input into a feeding cavity of the concentration filter after being pressurized by a pressurizing pump.

Description

Technical Field

[0001] The present disclosure relates to the technical field of high-pressure solid-liquid mixture filtering equipment, and in particular to a dehydration system of a solid-liquid dispersion system for removing a dispersant in a solid-liquid mixed dispersion system. Background Art

[0002] Solid wastewater is often produced in the chemical, metallurgical, mining and sewage treatment processes. The solids in it need to be recycled or harmlessly treated, and the water in it needs to be recycled and reused. The lower the water content of the treated solids, the better, and the lower the solid content in the recovered water, the better. Therefore, dehydration technology is widely used in mining, metallurgy, chemical industry, environmental protection and other industries. It is an important method in the operation of separation units. It is an industrial technology that removes the dispersant-clear liquid in the solid-liquid dispersion system from the solid-liquid dispersion system and increases the concentration of the dispersed substance-solid in the residual turbid liquid (dehydration).

[0003] The dehydration system currently used in industry is based on sedimentation technology. It uses the difference in the characteristics of different liquid and solid substances in the solid-liquid dispersion system to achieve the solid-liquid separation goal of bottom thickening and top clarification by the combined action of gravity, buoyancy and system resistance. Solid-containing wastewater usually has the characteristics of large flow, low concentration and low recovery value. The "sedimentation and concentration + filtration dehydration" technology and "multi-stage sedimentation and concentration + deep cone sedimentation and concentration dehydration" technology generally used in industry at present. The current free sedimentation is for solid-liquid systems with low concentrations. In the initial stage of sedimentation, under the dual forces of gravity and liquid buoyancy, large particles have a faster descending speed and small particles have an extremely slow sedimentation speed. At this stage, due to the large distance between solid particles, there is no influence between solid particles, so it is called free sedimentation. At this stage, if the diameter of the solid particles is small and the recycled water is required to be relatively clean, it is usually chosen to extend the residence time of the solid-liquid system, that is, to increase the volume of the sedimentation tank to achieve it. This requires a huge site area. In order to speed up sedimentation, interference sedimentation is used for free sedimentation in the prior art. As sedimentation proceeds and the concentration increases to a certain extent, the sedimentation rate of solid particles decreases. This is because the distance between solid particles becomes smaller, and the mutual influence increases. In order to increase the sedimentation rate of these two stages, it is usually necessary to add expensive flocculants so that small solid particles attach to the large particles to become larger particles, thereby increasing the sedimentation rate. This interference sedimentation will inevitably increase costs and pollute the environment due to the use of flocculants. In addition, in order to increase the solid content of the final underflow and reduce the floor space, the "multi-stage thickening with high-pressure deep cone thickening at the final stage" technology is usually adopted. The so-called deep cone thickening dehydration is an improved form of sedimentation thickening. It uses the compression sedimentation theory to raise the traditional sedimentation tank, improve the cone bottom angle and other ancillary facilities, so that the high-concentration mixture settled at the cone bottom is subjected to a higher liquid column pressure, thereby achieving the purpose of solid dehydration. This will take up a huge vertical space.

[0004] In addition, the industry usually uses a sedimentation tank to complete the dehydration task. The sedimentation tank is a wide-mouth, cone-bottomed device with a built-in rotary rake at the bottom. The rake frame is placed on the top of the wide-mouthed device and is used to arrange the liquid inlet, the dosing port, and the lifting and rotating power facilities of the rotary rake. Due to the special equipment shape and operation requirements, all current sedimentation tanks are normal pressure equipment. If there is a certain pressure in the state of the incoming material dispersion system, the system pressure must be released first to make it a normal pressure system before solid-liquid separation can be performed. However, in actual industrial processing systems, the solid-liquid dispersion system generated is usually a high-temperature and high-pressure system or dispersion system. For example, the coal chemical black water (turbid water containing solid coal ash particles) system has a black water pressure of 65 bar and a temperature of 240°C. In order to meet the current dehydration technical requirements, the black water system is first cooled and decompressed. When the system reaches normal temperature and pressure, it enters the sedimentation tank dehydration system. The recovered clean water is pressurized to a certain pressure before returning to the gasifier. The dehydrated mud is dehydrated in the vacuum filter and then landfilled.

[0005] Therefore, the current liquid-solid system dehydration process has the following main drawbacks: large footprint: giant sedimentation tanks with diameters of tens of meters or even more than one hundred meters occupy too much area; poor environment: many equipment, normal pressure or even open operation, which makes it difficult to avoid leakage and causes poor working environment; high operating costs: relatively worthless or low-value solids in wastewater, flocculants with a unit price of more than 10,000 yuan are added during the operation process, and a considerable part of them enter the water without combining with solid particles, which not only causes waste of operating costs, but also causes the recovered clean water and solid substances to be contaminated by flocculants. Moreover, this treatment method wastes a lot of heat and power energy, so there is an urgent need for a dehydration system that is environmentally friendly, occupies a small area, and can reduce or even eliminate the need to add flocculants to treat solid-liquid dispersions. It is best to be able to directly perform solid-liquid separation without unloading the pressure and cooling the mixed dispersion system to achieve the dehydration effect, and then recover the pressurized clear liquid to avoid the waste of pressure energy.

[0006] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0007] In view of this, the present disclosure provides a dehydration system for a solid-liquid dispersion system, which is environmentally friendly and occupies a small area. It can directly perform dehydration treatment without depressurization and at high temperature to obtain high-pressure and high-temperature clear liquid, thereby saving energy.

[0008] Other features and advantages of the present disclosure will become apparent from the following detailed description, or may be learned in part by the practice of the present disclosure.

[0009] According to one aspect of an embodiment of the present disclosure, there is provided 1. a dehydration system for a solid-liquid dispersion system, comprising: a concentration filter and a pressure sedimentation tank, wherein the dilute liquid inlet of the concentration filter is connected to the dilute liquid outlet of the pressure sedimentation tank via a pressure pump, and the discharge port of the concentration filter is connected to the concentrated liquid inlet of the lower section of the pressure sedimentation tank via a regulating valve, wherein the concentration filter comprises: a closed shell, the interior of which is divided into an upper section, a middle section and a lower section by an upper tube sheet and a lower tube sheet circumferentially sealed to the inner wall thereof; a multi-tube filter core, arranged at the middle section of the closed shell, comprising a plurality of filter core tubes; Each filter core tube penetrates the upper tube plate and the lower tube plate, and has a permeation hole that forms a predetermined angle with the axial direction of the filter core tube. The high-pressure weak liquid delivered from the weak liquid inlet of the concentration filter via the pressure pump flows from the feed cavity between the upper tube plate and the feed inlet arranged at the upper section of the closed shell through the inlet hole located on the upper tube plate at a predetermined speed into the corresponding filter core tube, and flows out from the corresponding filter core tube outlet hole located on the lower tube plate, so that part of the liquid in the high-pressure weak liquid laterally penetrates into the clear liquid cavity between the inner wall of the closed shell and the outer wall of the multi-tube filter core through the permeation hole. The clear liquid in the clear liquid cavity is discharged through the clear liquid recovery hole arranged at the upper part of the middle section of the closed shell; and the concentrated liquid cone bucket is arranged at the lower section of the closed shell, and its cone bottom is sealed with the inner wall of the closed shell and faces the outlet hole of the filter core tube on the lower tube plate, so as to receive the concentrated liquid flowing out of the outlet hole, and the concentrated liquid is discharged through the discharge port arranged at its cone end; and the pressure sedimentation tank is vertically arranged, including: a closed tank shell, the upper section of which is a cylindrical weak liquid cavity, and the lower section of which is a sedimentation cone; a driving mechanism, including a driving mechanism along the axial direction of the closed tank shell A driving shaft is arranged in the closed tank shell, a driving motor is connected to one end of the driving shaft outside the closed tank shell, and a cone bottom rake is connected to one end of the driving shaft extending to the sedimentation cone and is adapted to the conical space of the sedimentation cone. The driving motor drives the cone bottom rake to rotate via the driving shaft to stir the solid-liquid dispersion system input through the raw material port arranged in the upper middle part of the cylindrical weak liquid chamber part or input through the concentrated liquid inlet and settled in the sedimentation cone, so that the liquid in the solid-liquid dispersion system rises to the cylindrical weak liquid chamber to form an upper layer of weak liquid, so as to be pressurized by the pressure pump and then input into the feed chamber of the concentration filter.

[0010] The dehydration system for solid-liquid dispersion according to the present disclosure is characterized in that the pressure in the closed tank shell is at least 0.5 bar higher than the atmospheric pressure.

[0011] The dewatering system of the solid-liquid dispersion according to the present disclosure is characterized in that the cone-bottom harrow discharges solid particles through the mud holes at the cone end of the sedimentation cone while rotating and tilling the solid-liquid dispersion in the sedimentation cone.

[0012] The dehydration system of the solid-liquid dispersion system according to the present disclosure is characterized in that it also includes: a flow guide arranged at the inlet hole of each upper tube plate, the flow guide is a tubular component, the diameter of the outlet end facing the inlet hole is 1 / 3 to 1 / 10 of the inner diameter of the filter core tube, and extends into the filter core tube for a predetermined length, and the drainage end facing the feed chamber is formed with a flanged annular plate, and the outer diameter of the annular plate is equal to the outer diameter of the filter core tube.

[0013] The dehydration system of the solid-liquid dispersion system according to the present disclosure is characterized in that it also includes: a middle partition plate, which is arranged between the upper tube plate and the lower tube plate in parallel with the vertical arrangement direction of the multi-tube filter element, and the edges around it are sealed and connected to the inner wall of the closed shell, the lower surface of the upper tube plate and the upper surface of the lower tube plate, so as to divide the clear liquid chamber into two or more sub-clear liquid chambers.

[0014] According to the dehydration system of the solid-liquid dispersion system disclosed in the present invention, it is characterized in that the predetermined angle is a right angle or an obtuse angle between the axis of the permeation hole and the flow direction of the fluid in the filter core tube, and the inlet hole of the upper tube plate is an inverted truncated cone.

[0015] The dehydration system of the solid-liquid dispersion system according to the present disclosure is characterized in that it also includes a backwash hole, which is arranged in the middle or lower part of the middle section of the closed shell and is connected to the clear liquid chamber, and backwash liquid is injected into the clear liquid chamber or a selected sub-clear liquid chamber via a backwash valve connected thereto and arranged outside the closed shell.

[0016] The dehydration system for solid-liquid dispersion according to the present disclosure is characterized in that the pressure in the filter core tube is 1-4 bar higher than the pressure in the clear liquid chamber.

[0017] The dehydration system of the solid-liquid dispersion system disclosed in the present invention is characterized in that it also includes a flocculant adding pipeline connected to the outlet end of the regulating valve so as to add flocculant to the concentrated liquid discharged from the discharge port of the concentrated liquid cone bucket.

[0018] The dehydration system of the solid-liquid dispersion system disclosed in the present invention is characterized in that the feed port at the upper section of the closed shell also receives the solid-liquid dispersion system from other sources at the same time.

[0019] In the embodiment of the present disclosure, according to the dehydration system of the solid-liquid dispersion system of the present disclosure, on the one hand, the advantage of the cross-flow filtration technology in rapid filtration in a low-concentration system is fully utilized, and a permeable hole having a predetermined angle with the axial direction of the filter core tube is used to form a filtration surface (the inner wall surface of the filter core tube) in a direction parallel to the flow direction of the solid-liquid dispersion system, thereby realizing a cross-flow filtration state. In this cross-flow filtration state, due to the pressure difference between the inside and outside of the filter core tube, the clear liquid flow direction in the solid-liquid dispersion system changes by nearly 90 degrees, and passes through the filtration surface vertically or slightly obliquely upward (close to an obtuse angle of 90 degrees). At the same time, the mixed system flowing through the filter surface in parallel is concentrated due to the loss of clear liquid, so that the solid particles cannot accumulate on the filter surface, but continue to move forward along the original flow direction until they flow out of the filter core tube, thereby realizing continuous solid-liquid separation, thereby completely overcoming the phenomenon of "muddy" of the recovered clear liquid due to insufficient residence time in sedimentation filtration, significantly reducing the residence time of the longest clarification stage of sedimentation, and eliminating the sedimentation tank volume that originally accounted for more than 90% of the sedimentation volume, thereby creating conditions for closed high-pressure sedimentation. On the other hand, the present disclosure adopts pressure sedimentation, and its pressure is several times that of the static pressure generated by the liquid column of the traditional deep cone sedimentation tank, which not only accelerates the pressure sedimentation speed, but also can further reduce the moisture in the solid particles. In addition, since the volume of the pressure sedimentation tank is significantly lower than that of the deep cone sedimentation tank, its cost will also be greatly reduced. Therefore, the dehydration and separation disclosed in the present invention has high quality, "clear water and dry solids", and occupies little space, which greatly saves the company's precious land resources and reduces or does not use flocculants, which can not only greatly reduce operating costs, but also reduce the pollution of flocculants to recycled water and recycled solids. More importantly, the whole process is closed operation to reduce leakage and improve the operating environment.

[0020] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0022] Figure 1 It is a schematic structural diagram of a dehydration system of a solid-liquid dispersion system according to an exemplary embodiment.

[0023] Figure 2A and 2B It is a schematic structural diagram of a filter core tube in a dehydration system according to an exemplary embodiment.

[0024] Figure 3A and 3B It is a schematic structural diagram of an upper tube plate in a dehydration system according to an exemplary embodiment. DETAILED DESCRIPTION

[0025] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be comprehensive and complete and will fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted.

[0026] In addition, the described features, structures or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. may be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the present disclosure.

[0027] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0028] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0029] It should be understood that although the terms first, second, third, etc. may be used herein to describe various components, these components should not be limited by these terms. These terms are used to distinguish one component from another component. Therefore, the first component discussed below can be referred to as the second component without departing from the teachings of the disclosed concepts. As used herein, the term "and / or" includes any one of the associated listed items and all combinations of one or more.

[0030] Those skilled in the art will appreciate that the drawings are merely schematic diagrams of example embodiments, and the modules or processes in the drawings are not necessarily necessary for implementing the present disclosure, and therefore cannot be used to limit the protection scope of the present disclosure.

[0031] Figure 1 FIG. 1 is a schematic diagram of a dehydration system for a solid-liquid dispersion system according to an exemplary embodiment. Figure 1 As shown, the embodiment of the present disclosure provides a dehydration system for a solid-liquid dispersion system, which uses a cross-flow filtration technology and a pressurized sedimentation technology to be superimposed, so that it has the ability to process a solid-liquid dispersion system in a closed pressurized environment, especially a low-solid content wastewater treatment, and to recover low-solid content clean water or other solvents and a low-water content solid or paste dehydration system. The cross-flow filtration technology is realized by the concentration filter 100 of the present disclosure, and the concentration filter 100 has a permeable hole that forms a predetermined angle with the axial direction of the filter core tube, and forms a filter surface (the inner wall surface of the filter core tube) in a direction parallel to the flow direction of the solid-liquid dispersion system, thereby realizing a cross-flow filtration state. In this cross-flow filtration state, under the action of the pressure difference between the inside and outside of the filter core tube, the flow direction of the clear liquid in the solid-liquid dispersion system changes by nearly 90 degrees, and passes through the filter surface vertically or slightly obliquely upward (close to an obtuse angle of 90 degrees). At the same time, the mixed system flowing through the filter surface in parallel is concentrated after losing the clear liquid, so that the solid particles cannot accumulate on the filter surface, but continue to move forward along the original flow direction until they flow out of the filter core tube, thereby realizing continuous solid-liquid separation. Compared with the existing technology, it greatly saves the dehydration step, recovers a large amount of pressure energy and heat energy, and reduces the need for frequent backwashing of the dehydration system.

[0032] Specifically, if Figure 1 As shown, the dehydration system of the solid-liquid dispersion system includes a concentration filter 100 and a pressure sedimentation tank 200. The dilute liquid inlet 110 of the concentration filter 100 is connected to the dilute liquid outlet 209 of the pressure sedimentation tank 200 through a pressure pump P, and the discharge port 128 of the concentration filter 100 is connected to the concentrated liquid inlet 208 of the lower section of the pressure sedimentation tank 200 through a regulating valve.

[0033] Specifically, the concentration filter 100 includes: a closed shell 101, a multi-tube filter core 107, and a concentrated liquid cone bucket 115. The closed shell 101 is divided into an upper section 104, a middle section 105, and a lower section 106 by an upper tube plate 102 and a lower tube plate 103 circumferentially sealed to the inner wall thereof. The middle section 105 is a part for realizing cross-flow filtration. The multi-tube filter core 107 is arranged in the middle section of the closed shell 101 so that the mixed system flowing through the filter surface in parallel is concentrated due to the loss of clear liquid through cross-flow filtration, and the accumulation of solid particles on the filter surface is significantly reduced or even eliminated. Specifically, the multi-tube filter core 107 is actually a component, including a plurality of filter core tubes 108 and an upper tube plate 102 and a lower tube plate 103 assembled with the plurality of filter core tubes 108. It looks like each filter core tube runs through the upper tube plate 102 and the lower tube plate 103. The filter core tube 108 can be screwed into the prefabricated threaded hole-shaped inlet hole 112 and outlet hole 113 on the upper tube plate 102 and the lower tube plate 103 by threaded connection. Alternatively, it can also be directly welded together.

[0034] The pressure sedimentation tank 200 includes a closed tank shell 201 and a driving mechanism. The upper section of the closed tank shell 201 is a cylindrical weak liquid chamber 202, and the lower section is a sedimentation cone 203. The driving mechanism includes: a driving shaft 205 arranged in the closed tank shell 201 along the axial direction of the closed tank shell 201, a driving motor 204 connected to one end of the driving shaft 205 outside the closed tank shell 201, and a cone bottom rake 206 connected to one end of the driving shaft 205 extending to the sedimentation cone 203 and adapted to the conical space of the sedimentation cone 203. The driving motor 204 drives the cone bottom rake 206 to rotate via the driving shaft 205, stirring the solid-liquid dispersion system input through the raw material port 207 set in the upper middle part of the cylindrical weak liquid chamber 202 or input through the concentrated liquid inlet 208 and settled in the sedimentation cone 203, so that the liquid in the solid-liquid dispersion system rises into the cylindrical weak liquid chamber 202 to form an upper layer of weak liquid, so as to be pressurized by the pressure pump P and then input into the feed chamber 111 of the concentration filter 100.

[0035] Figure 2A and 2B FIG. 1 is a schematic diagram showing the structure of a filter core tube in a dehydration system according to an exemplary embodiment. Figure 2AAs shown, each filter core tube 108 has a permeable hole 109 transverse to the axial direction of the filter core tube 108. Although a tubular deep hole is shown here, it may not be a tubular hole, but a permeable mesh structure. For example, the filter core tube 108 is a ceramic tube. The tube wall of the ceramic tube has a pore structure that can play a role in penetrating liquid. This pore structure itself is not a straight tube structure, but a sponge-like pore structure. Therefore, during the process of infiltration from the inside to the outside, the liquid does not flow in the straight tube as shown in the figure, but seeps out from the inside to the outside from a random pore structure. For this reason, when the present application uses a ceramic tube as the filter core tube 108, a permeable membrane 128 will be attached to the ceramic tube. The predetermined angle between each permeable hole 109 and the direction of fluid flow can be 90 degrees, or it can be an obtuse angle slightly greater than 90, such as 91-95 degrees. By making the filtering direction and the fluid flow velocity direction form a predetermined angle, on the one hand, the mixed system filtered through the filtering surface loses clear liquid laterally due to the pressure difference, and on the other hand, does not affect the flow velocity of the mixed system, reducing the deposition of solid particles at the orifice of the penetration hole 109. Even if there is deposition, it will be carried away by the subsequent fluid impact. Therefore, the high-pressure dispersion system flows from the feed cavity 111 between the upper tube plate 102 and the feed port 110 arranged at the upper section 104 of the closed shell 101 through the inlet hole 112 located on the upper tube plate into the corresponding filter core tube 108 at a predetermined speed, and flows out from the outlet hole 113 of the corresponding filter core tube 108 located on the lower tube plate 103, so that part of the liquid (that is, the clear liquid) in the high-pressure dispersion system laterally penetrates into the clear liquid cavity 114 between the inner wall of the closed shell 101 and the outer wall of the multi-tube filter core 107 through the penetration hole 109.

[0036] By adopting this structure, the cross-flow filtration and the dehydration process of the high-pressure dilute liquid are realized. This process not only does not require the pressure relief of the high-pressure dilute liquid, but also requires the use of the high pressure contained therein. Without the existence of such high pressure, a pressure difference conducive to filtration will not be formed between the inside of the multi-tube filter element 107 and the clear liquid chamber 114, and it is difficult to achieve such cross-flow filtration. If the raw material input dispersion system is not from the pressure sedimentation tank 200, but from other high-pressure dilute liquids or solid-liquid mixed systems from other sources. Therefore, the pressure energy in the high-pressure solid-liquid mixed system is directly used to eliminate the pressure relief and cooling process in the treatment of industrial waste slag water, and the waste heat and waste energy in the existing industry are fully utilized as a treatment tool, which is an effective way to achieve the goals of energy saving and consumption reduction. In particular, it brings huge economic profits from carbon trading to high-energy-consuming industries. It should be pointed out that the aperture of the permeable hole 109 is usually smaller than the average particle diameter of the solid particles in the high-pressure dilute liquid, so as to prevent the solid particles from entering the clear liquid chamber with the liquid through the permeable hole 109. This is a conventional setting of the aperture in a filtration process, so it will not be repeated here.

[0037] In order to realize the cross-flow filtration using pressure difference, the pressure in the filter core tube 108 is 1-4 bar higher than the pressure in the clear liquid cavity. However, the pressure difference of 0-1 bar is also possible. Before the filtration starts, the high-pressure dilute liquid is a pressurized or pressurized system. After filtration, it is divided into two streams, one of which is the dense phase flow inside the thickened multi-tube filter core 107, which is basically consistent with the inlet pressure; the other stream is the clear liquid in the clear liquid cavity 114. Because the clear liquid penetrates into the clear liquid cavity 114 through the tube wall of the multi-tube filter core 107, due to the need to overcome the filtration resistance, the pressure of the clear liquid cavity 114 is lower than the pressure of the dense phase flow of the solid-liquid mixed system inside the multi-tube filter core 107. The outlet pressure is usually controlled to be about 1 to 4 bar lower than the dense phase liquid, thereby forming a filtration pressure difference.

[0038] The cone bottom 116 of the concentrated liquid cone hopper 115 arranged at the lower section 106 of the closed shell 101 is sealed and connected to the inner wall of the closed shell 101 and faces the outlet hole 113 of the filter core tube 107 on the lower tube plate 103, so as to receive the concentrated liquid 117 flowing out of the outlet hole. The lower opening diameter of the concentrated liquid cone hopper 115 of the hollow cone structure is small, which is convenient for collecting the concentrated liquid discharged from the lower part of the filter tube. After the cone is narrowed, the downward flow rate of the fluid is increased, so that the solid particles in the discharged concentrated liquid are further separated under the action of gravity and initial velocity, and reach the lower part of the columnar weak liquid chamber 202 of the pressure settling tank 200 as soon as possible, without excessively stirring the upper weak liquid layer, and also promoting the sedimentation of the columnar weak liquid chamber 202 to the sedimentation cone 203 as soon as possible.

[0039] Therefore, optionally, although the above-mentioned cross-flow filtration can obtain the clear liquid of high-pressure dilute liquid and the dehydration result (i.e., concentrated liquid 117), this dehydration result is also incomplete. Due to its rapid passage through the filter element tube 108, there is still a certain amount of liquid in the preliminary dehydrated solid-liquid dispersion system entering the concentrated liquid cone bucket 115. To this end, the dehydration system disclosed in the present invention also includes conveying the concentrated liquid 117 to the lower part of the columnar dilute liquid chamber 202 in the upper section of the closed tank shell 201 through a regulating valve for further pressure sedimentation to obtain mud with lower humidity. Optionally, for a solid-liquid system that requires a flocculant, a pipeline for supplementing the flocculant can be connected at the outlet of the regulating valve to increase the condensation of the concentrated liquid 117 and increase the sedimentation of the solid after the concentrated liquid 117 enters the lower part of the columnar dilute liquid chamber 202.

[0040] The upper part of the closed tank shell 201 is a columnar weak liquid chamber 202, and the upper part is provided with weak liquid formed by pressure sedimentation. The upper part of the columnar weak liquid chamber 202 is provided with a weak liquid outlet 209, and the weak liquid outlet 209 is connected to the weak liquid inlet 110 of the closed shell 101 arranged in the concentration filter 100 through a pressure pump P. The weak liquid in the weak liquid chamber 202 is extracted by the pressure pump P, and the liquid in the concentrated liquid reaching the sedimentation tank can also be promoted to move upward under the suction of the pressure pump P, and further enter the weak liquid layer, thereby promoting the sedimentation of solid particles and the dehydration process.

[0041] Optionally, a weak liquid injection port 110 is arranged at the upper section of the closed shell 101, so that the weak liquid in the weak liquid chamber 202 is pumped to the weak liquid injection port 110 through the weak liquid recovery valve by the pressure pump P, and then injected into the feed chamber, which can preliminarily dilute the solid-liquid dispersion system from other sources in the feed chamber. Through this preliminary dilution, more weak liquid can be more easily filtered into clear liquid during the cross-flow filtration process.

[0042] The clear liquid in the clear liquid chamber 114 is extracted through a clear liquid recovery hole 118 arranged at the upper part of the middle section 105 of the closed shell 101 and connected to the clear liquid chamber 114. The clear liquid recovery hole 118 is connected to a clear liquid recovery valve 119 arranged outside the closed shell to discharge the clear liquid. The extraction is usually performed by a clear liquid pump (not shown).

[0043] In order to further promote cross-flow filtration and prevent solid particles in high-pressure dilute liquid from depositing and adhering to the orifice of the permeation hole 109, the technical solution disclosed in the present invention arranges a flow guide 120 at the inlet hole 112 of each upper tube plate 102. The flow guide 120 is a tubular component, and the diameter of its outlet end facing the inlet hole is 1 / 3 to 1 / 10 of the inner diameter of the filter core tube 108, and extends into the filter core tube for a predetermined length. The flow guide end facing the feed cavity forms a flanged annular plate, and the outer diameter of the annular plate is equal to the outer diameter of the filter core tube, or slightly larger. In actual use, the diameter of the filter core tube 108 is generally large, and the flow velocity in the tube is less than 1m / s, while the flow guide 120 has a smaller inner diameter, so that the inlet flow velocity of the flow guide 120 can reach 2 to 10m / s. On the one hand, a higher initial velocity is given to the inlet liquid-solid system. Therefore, by virtue of the high density and large inertia of the solids in the high-pressure diluted liquid, the solid particles are thrown farther along the axial direction of the filter core, and even directly thrown to the end of the filter core tube 108 or its outlet. In this way, the solid concentration on the filter surface is reduced, providing convenient conditions for improving the filtration flux. On the other hand, after the high-pressure diluted liquid is introduced into the filter core tube 108 by the flow guide 120, since the filter core tube 108 is filled with high-pressure diluted liquid, the newly introduced high-pressure diluted liquid is mixed with the high-pressure diluted liquid with a slower flow rate nearby at the outlet of the flow guide 120 (inside the filter core tube 108), producing a Venturi effect, that is, a relatively low-pressure area is generated at the center of the filter core tube 108 (the higher the flow rate, the lower the pressure), which can reduce the force of dragging some solid particles to the inner wall of the filter core tube 108, thereby reducing the solid particles attached to the filter surface. In addition, since the high-pressure diluted liquid has an incompressible characteristic, the liquid in the center of the filter core tube 108 will not decrease, thereby reducing the tendency of solid particles generated by filtering the clear liquid to move to the filter surface. In this way, the cross-flow filtration effect is further promoted and the possibility of the permeation holes being blocked is reduced, thereby reducing the need for backwashing of the filter core tube 108.

[0044] In the actual mixed dispersion filtering process, the filter device must be reused, and backwashing is an indispensable process. However, the backwashing of conventional filtering devices requires stopping the machine for backwashing, which will inevitably affect the entire mixed dispersion filtering process. And this parking will also affect the arrangement of upstream and downstream processes. In order to avoid parking as much as possible or reduce the impact of parking, the present disclosure sets a middle partition 121 between the upper tube plate and the lower tube plate in parallel to the vertical arrangement direction of the multi-tube filter core 107, so that the edges of the middle partition 121 are sealed and connected to the inner wall of the closed shell, the lower surface of the upper tube plate and the upper surface of the lower tube plate, thereby dividing the clear liquid cavity 114 into two or more sub-clear liquid cavities. In this way, the multi-tube filter core 107 is divided into two or more groups of filter core tubes 108 by the middle partition 121, so that the middle partition 121 also divides the clear liquid cavity 114 into two or more sub-clear liquid cavities that are not connected to each other, and each sub-clear liquid cavity contains a group of filter core tubes 108. In this way, if there is a situation where backwashing is required, the filtering process of one group of filter core tubes 108 can be suspended and backwashing can be performed, while the filtering process of the other groups of filter core tubes 108 continues. By backwashing in this way in turn, the production impact caused by the overall shutdown can be significantly reduced.

[0045] In order to realize partial filtering of the core tube 108, backwashing holes 122 may be provided for different sub-clear liquid chambers. The backwashing hole 122 is arranged in the middle or lower part of the middle section of the closed shell 101, and is connected to the clear liquid chamber or the corresponding sub-clear liquid chamber, and backwashing liquid is injected into the clear liquid chamber or a selected sub-clear liquid chamber via a backwashing valve connected thereto and arranged outside the closed shell 101. Optionally, the backwashing liquid is the clear liquid outputted via the clear liquid recovery valve, or directly industrial tap water or other clean liquid.

[0046] Figure 3A and 3B FIG. 1 is a schematic diagram showing the structure of an upper tube plate in a dehydration system according to an exemplary embodiment. Figure 3A and 3B As shown, the upper and lower tube sheets are upper and lower mounting steel plates used to fix the filter tube 108. The tube sheets are provided with the same number of holes as the filter tubes, and the holes are in the shape of a truncated cone. The large diameter of the truncated cone hole of the upper tube sheet faces downward, and the large diameter of the truncated cone hole of the lower tube sheet faces upward. The two ends of the filter tube are respectively embedded in the large diameter section of the truncated cone hole of the tube sheet. The outer diameter of the tube sheet is substantially consistent with the inner diameter of the closed shell 101.

[0047] According to the technical solution disclosed in the present invention, on the one hand, the advantage of cross-flow filtration technology in rapid filtration in low-concentration systems is fully utilized, and a permeable hole having a predetermined angle with the axial direction of the filter core tube is used to form a filter surface (the inner wall surface of the filter core tube) in a direction parallel to the flow direction of the solid-liquid dispersion system, thereby realizing a cross-flow filtration state. In this cross-flow filtration state, due to the pressure difference between the inside and outside of the filter core tube, the flow direction of the clear liquid in the solid-liquid dispersion system changes by nearly 90 degrees, and passes through the filter surface vertically or slightly obliquely upward (close to an obtuse angle of 90 degrees). At the same time, the mixed system flowing through the filter surface in parallel is concentrated after losing the clear liquid, so that the solid particles cannot accumulate on the filter surface, but continue to move forward along the original flow direction until flowing out of the filter core tube, thereby realizing continuous solid-liquid separation, thereby completely overcoming the phenomenon of "running muddy" of the recovered clear liquid due to insufficient residence time in sedimentation filtration, significantly reducing the residence time of the longest clarification stage of sedimentation, and eliminating the sedimentation tank volume that originally accounted for more than 90% of the sedimentation volume, thereby creating conditions for closed high-pressure sedimentation. On the other hand, the present invention adopts pressure sedimentation, and its pressure is several times that of the static pressure generated by the liquid column of the traditional deep cone sedimentation tank, which not only accelerates the pressure sedimentation speed, but also can further reduce the moisture in the solid particles. In addition, since the volume of the pressure sedimentation tank is significantly lower than that of the deep cone sedimentation tank, its cost will be greatly reduced. Therefore, the dehydration separation of the present invention is of high quality, "clear water and dry solid", and occupies less space, greatly saving the company's precious land resources, reducing or not using flocculants, not only can greatly reduce operating costs, but also can reduce the pollution of flocculants to recycled water and recycled solids. More importantly, the whole process is closed operation, which reduces leakage and improves the operating environment.

[0048] The exemplary embodiments of the present disclosure are specifically shown and described above. It should be understood that the present disclosure is not limited to the detailed structures, configurations or implementations described herein; on the contrary, the present disclosure is intended to cover various modifications and equivalent configurations included in the spirit and scope of the appended claims.

Claims

1. A dehydration system for a solid-liquid dispersion system, comprising: The concentrating filter and the pressure settling tank are characterized in that the dilute liquid inlet of the concentrating filter is connected to the dilute liquid outlet of the pressure settling tank through a pressure pump, and the discharge port of the concentrating filter is connected to the concentrated liquid inlet of the lower section of the pressure settling tank through a regulating valve, wherein The concentration filter comprises: A closed shell, the interior of which is divided into an upper section, a middle section and a lower section by an upper tube sheet and a lower tube sheet circumferentially sealed to the inner wall thereof; A multi-tube filter element is arranged at the middle section of the closed shell, comprising a plurality of filter core tubes, each filter core tube penetrating the upper tube plate and the lower tube plate, and having a transverse permeation hole in the axial direction of the filter core tube, wherein the high-pressure weak liquid delivered from the weak liquid inlet of the concentration filter via the pressure pump flows from the feed cavity between the upper tube plate and the feed inlet arranged at the upper section of the closed shell via the inlet hole located on the upper tube plate into the corresponding filter core tube at a predetermined speed, and flows out from the corresponding filter core tube outlet hole located on the lower tube plate, so that part of the liquid in the high-pressure weak liquid transversely penetrates into the clear liquid cavity between the inner wall of the closed shell and the outer wall of the multi-tube filter element via the permeation hole, and the clear liquid in the clear liquid cavity is discharged via the clear liquid recovery hole arranged at the upper part of the middle section of the closed shell; and A concentrated liquid cone hopper is arranged at the lower section of the closed shell, with its cone bottom sealedly connected to the inner wall of the closed shell and facing the outlet hole of the filter core tube on the lower tube plate, so as to receive the concentrated liquid flowing out of the outlet hole, and the concentrated liquid is discharged through the discharge port arranged at its cone end; and The pressure settling tank is vertically arranged and comprises: The closed tank shell has a cylindrical thin liquid chamber in the upper section and a sedimentation cone in the lower section; The driving mechanism comprises a driving shaft arranged in the closed tank shell along the axial direction of the closed tank shell, a driving motor connected to one end of the driving shaft outside the closed tank shell, and a cone bottom rake connected to one end of the driving shaft extending to the sedimentation cone and adapted to the conical space of the sedimentation cone. The driving motor drives the cone bottom rake to rotate via the driving shaft to stir the solid-liquid dispersion system inputted via the raw material port arranged in the middle and upper part of the cylindrical weak liquid chamber part or inputted via the concentrated liquid inlet and settled in the sedimentation cone, so that the liquid in the solid-liquid dispersion system rises into the cylindrical weak liquid chamber to form an upper layer of weak liquid, so as to be pressurized by the pressure pump and inputted into the feed chamber of the concentration filter.

2. The dehydration system of the solid-liquid dispersion according to claim 1, characterized in that The pressure in the closed tank housing is at least 0.5 bar higher than the atmospheric pressure.

3. The dehydration system of the solid-liquid dispersion according to claim 1, characterized in that The cone bottom harrow discharges solid particles through the mud holes at the cone end of the sedimentation cone while rotating and tilling the solid-liquid dispersion in the sedimentation cone.

4. The dehydration system of the solid-liquid dispersion according to claim 1, characterized in that It also includes: a flow guider arranged at the inlet hole of each upper tube plate, the flow guider is a tubular component, the diameter of the outlet end facing the inlet hole is 1 / 3 to 1 / 10 of the inner diameter of the filter core tube, and extends into the filter core tube for a predetermined length, and the flow guide end facing the feed chamber is formed with a flanged annular plate, and the outer diameter of the annular plate is equal to the outer diameter of the filter core tube.

5. The dehydration system of the solid-liquid dispersion according to claim 1, characterized in that Also includes: The middle partition is arranged between the upper tube plate and the lower tube plate in parallel with the vertical arrangement direction of the multi-tube filter element, and the edges around it are sealed and connected to the inner wall of the closed shell, the lower surface of the upper tube plate and the upper surface of the lower tube plate, so as to divide the clear liquid chamber into two or more sub-clear liquid chambers.

6. The dehydration system of the solid-liquid dispersion according to claim 1, characterized in that The permeation hole is a pore structure in the filter core tube, and the inlet hole of the upper tube plate is in the shape of an inverted truncated cone.

7. The dehydration system of the solid-liquid dispersion according to claim 6, characterized in that It also includes a backwash hole, which is arranged in the middle or lower part of the middle section of the closed shell and is connected to the clear liquid chamber. Backwash liquid is injected into the clear liquid chamber or a selected sub-clear liquid chamber via a backwash valve connected to it and arranged outside the closed shell.

8. The dehydration system of the solid-liquid dispersion according to claim 1, characterized in that The pressure in the filter core tube is no higher than the pressure in the clear liquid chamber by no more than 4 bar.

9. The dehydration system of the solid-liquid dispersion according to any one of claims 1 to 8, characterized in that The invention also comprises a flocculant adding pipeline connected to the outlet end of the regulating valve so as to add flocculant to the concentrated liquid discharged from the discharge port of the concentrated liquid cone bucket.

10. The dehydration system of the solid-liquid dispersion according to claim 9, characterized in that The feed inlet at the upper section of the closed shell also receives solid-liquid dispersions from other sources.

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