Pilot plant test system of quick-sand high-density sedimentation tank

Abstract

The utility model provides a pilot plant test system for a quick-sand high-density sedimentation tank, and the pilot plant test system comprises an adjusting area which receives a fluid to be treated and can adjust the flow of the fluid in the adjusting area; the mixing area is in fluid communication with the adjusting area, and the fluid can be subjected to coagulation treatment in the mixing area; an adding zone in fluid communication with the mixing zone, in which a loading medium can be added to the fluid; the flocculation zone is communicated with the fluid in the feeding zone, and the fluid can be flocculated in the flocculation zone; the settling zone is in fluid communication with the flocculation zone, and the fluid can be subjected to settling treatment in the settling zone to form a sludge mixture; the sludge reflux device is in fluid communication with the settling zone at the bottom of the settling zone and is configured to be capable of treating the sludge mixture to form sludge and recovery fluid; the adding device is configured to be capable of respectively adding corresponding medicaments into the mixing area, the adding area and the flocculation area; and the buffer device is in fluid communication with the sludge reflux device to receive the recycled fluid and is configured to be capable of conveying the recycled fluid to the adding area.

Description

Technical Field

[0001] This disclosure relates to the field of water treatment, and more specifically, to a pilot-scale system for a high-density rapid sand sedimentation tank. Background Technology

[0002] High-density quick-sand sedimentation tanks are a highly advanced water treatment process already in commercial application. They combine media addition, recovery, and recirculation with high-density sedimentation technology, offering advantages such as free settling, inclined tube sedimentation, contact flocculation, and rapid settling of loaded flocs. By adding loading media to the high-density quick-sand sedimentation tank, the flocculation effect is improved, significantly accelerating subsequent sludge-water separation, enhancing wastewater treatment efficiency, resulting in superior effluent quality and stronger shock resistance. Compared to other sedimentation technologies, high-density quick-sand sedimentation tanks have higher upward flow velocities, require less floor space, and have a more compact system. Therefore, high-density quick-sand sedimentation tanks are primarily used to remove suspended solids, total phosphorus (TP), and fluorides from water.

[0003] The operational performance testing or simulation of high-density quick-sand sedimentation tanks requires a pilot-scale system, as traditional laboratory-scale platforms are insufficient for accurate testing. The core technological elements of high-density quick-sand sedimentation tanks include two aspects: the formation of coagulated flocs and the separation of sand and sludge mixtures. Floc formation is primarily influenced by factors such as the concentrations of coagulant, flocculant, and loading medium, as well as the hydraulic load of the high-density quick-sand tank. Separation of the sand and sludge mixture is mainly affected by factors such as sludge concentration, loading medium concentration, sludge return ratio, and the operating pressure and model of the hydrocyclone. Due to the rapid settling velocity of the flocs, it is difficult to test the maximum hydraulic load of the flocs at different flocculant concentrations under limited laboratory equipment. Furthermore, laboratory-scale platforms cannot simulate the separation effect of hydrocyclones on sand and sludge under different sludge return ratios and operating pressures; therefore, it is impossible to evaluate the treatment effect of high-density quick-sand sedimentation tanks on target pollutants at different dosages.

[0004] For practical water treatment projects, pilot-scale testing using a pilot system is essential for evaluating the feasibility of high-density quick-sand sedimentation tanks and determining suitable operating parameters. However, current data on pilot-scale systems for high-density quick-sand sedimentation tanks are scarce. Even when similar designs exist, there is room for optimization in areas such as sludge removal and chemical dosing, and their applicability to influent flow rates and hydrocyclone testing conditions is insufficient. Furthermore, due to the weight of the loading medium, it tends to accumulate in the corners of the reaction zone, preventing the full utilization of the medium. Some similar designs incorporate sludge scrapers in the sedimentation zone, resulting in larger system sizes, insufficient integration, and unsuitability for rapid pilot-scale testing scenarios.

[0005] Therefore, there is a need in the art for a pilot-scale system of a high-density quick-sand sedimentation tank that can solve the above problems. Utility Model Content

[0006] Therefore, the purpose of this disclosure is to provide a pilot-scale system for a high-density quick-sand sedimentation tank. The pilot-scale system can be used to verify the feasibility of the high-density quick-sand sedimentation tank process for treating target water bodies, guide the design of actual engineering processes, optimize the operating parameters of the high-density quick-sand sedimentation tank process (including sludge return ratio, loading medium and flocculant concentration, hydrocyclone test conditions, etc.), and guide actual production operation.

[0007] The above objectives are achieved through a pilot-scale system of a high-density quick-sand sedimentation tank as described below.

[0008] This disclosure provides a pilot-scale system for a high-density quicksand sedimentation tank. The pilot-scale system includes: a conditioning zone for receiving fluid to be treated and for regulating the flow rate of the fluid; a mixing zone fluidly connected to the conditioning zone for receiving fluid from the conditioning zone and for coagulating the fluid therein; a dosing zone fluidly connected to the mixing zone for receiving fluid from the mixing zone and for adding a loading medium to the fluid therein; a flocculation zone fluidly connected to the dosing zone for receiving fluid from the dosing zone and for flocculating the fluid therein; and a sedimentation zone fluidly connected to the... The flocculation zone is fluidly connected to receive fluid from the flocculation zone and can perform sedimentation treatment therein to form a sludge mixture; a sludge return device, fluidly connected to the bottom of the sedimentation zone to receive the sludge mixture from the sedimentation zone, is configured to treat the sludge mixture to form sludge and recycled fluid; a dosing device is configured to dosing corresponding agents into the mixing zone, the dosing zone, and the flocculation zone respectively; and a buffer device, fluidly connected to the sludge return device to receive the recycled fluid, is configured to transport the recycled fluid to the dosing zone. The recycled fluid enables the recycling of the loading medium, and the buffer device prevents the recycled fluid from impacting the fluid within the tank.

[0009] The pilot-scale system of the high-density quick-sand sedimentation tank according to this disclosure may also have one or more of the following features, individually or in combination.

[0010] In one embodiment, the buffer device is disposed above the dosing zone, and its bottom is in fluid communication with the dosing zone. The recovered fluid can flow to the dosing zone by its own gravity, saving energy and resulting in a compact overall structure.

[0011] In one embodiment, the dosing device has multiple first pipes leading to the upper part of the dosing zone, the buffer device, and the bottom of the flocculation zone, respectively. This design allows for the study of the impact of different dosing points on the reaction effect.

[0012] In one embodiment, the dosing device is configured to adjust the amount of loading medium dispensed into the dosing area.

[0013] In one embodiment, the dosing zone is in fluid communication with the flocculation zone via a second pipe.

[0014] In one embodiment, the depth of the flocculation zone is greater than the depth of the dosing zone, and the second conduit connects the bottom wall of the dosing zone to the side wall of the flocculation zone. This design allows the fluid to flow automatically downstream under its own gravity and provides installation space for the second conduit.

[0015] In one embodiment, a variable frequency mixer is provided in each of the mixing zone, the dosing zone, and the flocculation zone, wherein the variable frequency mixer in the flocculation zone is a double-layer variable frequency mixer. The double-layer structure can enhance the mixing effect of the loaded flocs and prevent the loaded medium from depositing at the bottom of the flocculation zone. In addition, a good mixing effect can be achieved in the flocculation zone without the need for a guide tube.

[0016] In one embodiment, the sedimentation zone includes a clarification zone and a sludge hopper zone, the sludge hopper zone being located below the clarification zone and having a funnel shape that tapers towards the bottom of the sludge hopper zone. This facilitates the sedimentation of the sludge mixture, allowing the sludge mixture to be discharged using a pump without the need for a scraper, significantly reducing the system volume.

[0017] In one embodiment, both the flocculation zone and the clarification zone are equipped with observation windows. This allows operators to directly observe the formation of the loaded flocs and the sludge level, and to promptly understand the operating status of the high-density quick-sand sedimentation tank.

[0018] In one embodiment, the pilot-scale system further includes multiple sampling ports. This allows for the measurement of the concentration of the loading medium in different areas, and monitoring of the operational status of the high-density quicksand sedimentation tank.

[0019] In one embodiment, the mixing zone, the dosing zone, the flocculation zone, and the sedimentation zone are arranged in the same tank and separated by corresponding partition walls. The pilot-scale system further includes multiple first weir plates, each with an adjustable height and positioned at the top of its respective partition wall. This ensures uniform fluid distribution and stable liquid level.

[0020] In one embodiment, the pilot-scale system further includes a second weir plate, which has an adjustable height and is disposed on the effluent device in the clarification zone. Therefore, the effluent flow rate can be controlled under different reaction conditions to ensure effluent quality.

[0021] In one embodiment, the bottom of the dosing zone and / or the flocculation zone is provided with an inclined plate extending from its sidewall to its bottom wall. This design helps to promote the uniform distribution and mixing of the loading medium.

[0022] In one embodiment, the sludge return device includes at least two sets of detachable hydrocyclones, the outlets of which are in fluid communication with the buffer device. This provides greater flexibility.

[0023] In one embodiment, the hydrocyclone is located above the dosing zone.

[0024] In one embodiment, the remaining portion of the sludge return device, excluding the hydrocyclone, is at least partially disposed on one side of at least one of the dosing zone, the flocculation zone, and the sedimentation zone.

[0025] In one embodiment, the pilot-scale system is no more than 4 m in length and no more than 2 m in width. This compact design allows for fully integrated assembly of the system in the factory, enabling it to be transported to the testing site by conventional trucks without additional installation work, thus ensuring rapid startup of the pilot-scale system.

[0026] In one embodiment, the sludge return device includes a variable frequency pump. This allows the sludge return ratio to be adjusted as needed.

[0027] The above-mentioned structure improves the degree of integration, is compact, and facilitates installation and transportation. Attached Figure Description

[0028] The advantages and objectives of this disclosure will be better understood from the preferred embodiments described below in conjunction with the accompanying drawings. The drawings are not to scale in order to better illustrate the relationships between the components. In the drawings:

[0029] Figure 1 A schematic diagram of a pilot-scale system of a high-density quicksand sedimentation tank according to an embodiment of the present disclosure is shown, with bent arrows in the tank body schematically indicating the direction of fluid flow;

[0030] Figure 2 A partial schematic diagram of a pilot-scale system of a high-density quicksand sedimentation tank according to an embodiment of the present disclosure is shown.

[0031] Figure 3 A partial schematic diagram of a pilot-scale system of a high-density quicksand sedimentation tank according to an embodiment of the present disclosure is shown.

[0032] Figure 4 A schematic top view of a pilot-scale system of a high-density quicksand sedimentation tank according to an embodiment of the present disclosure is shown. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0034] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not necessarily indicate a quantity limitation. The terms “comprising,” “including,” or “having,” and similar terms mean that the element or object preceding the word encompasses the element or object listed following the word and its equivalents, without excluding other elements or objects. The terms “connected” or “connected,” and similar terms are not limited to the physical or mechanical connection or connection shown in the drawings, but may include equivalent connections or connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” etc., are used only to indicate relative positional relationships, which may change accordingly when the absolute position of the described object changes.

[0035] See below Figures 1 to 4 The embodiments of this disclosure are described in detail.

[0036] The performance of a high-density quick-sand sedimentation tank is usually affected by both the water quality of the water to be treated and the control parameters.

[0037] Specifically, the type and concentration of target pollutants in the fluid to be treated (generally wastewater, also known as the water body to be treated) are among the key factors affecting the operational performance of a high-density quicksand sedimentation tank. Different pollutant indicators, such as fluoride, hardness, total phosphorus, and turbidity, as well as their concentration requirements, will determine the type and concentration level of the added chemicals, which in turn will affect the loading medium and flocculant concentration.

[0038] High-density quick-sand sedimentation tanks primarily rely on coagulation and flocculation, along with the rapid settling performance of the loaded flocs, to achieve efficient removal of target pollutants. The rapid settling performance of the loaded flocs is influenced by the control parameters of the high-density quick-sand sedimentation tank's operation. These parameters include the reagent dosing scheme, hydrocyclones, sludge return ratio, and hydraulic load. The reagent dosing scheme encompasses the loading medium, coagulant, and flocculant. The concentration relationship of these three substances is crucial to the formation of the loaded flocs. If the concentrations of the loading medium and flocculant are insufficient, the floc formation strength will be insufficient to withstand high hydraulic loads; conversely, if the concentrations of the loading medium and flocculant are too high, it will lead to increased operating costs. The sludge return ratio also has a significant impact on the operational performance of the high-density quick-sand sedimentation tank. Since high-density quick-sand sedimentation tanks do not have sludge thickening functions, a higher sludge return ratio is required to ensure stable system operation when the influent water quality is poor or the chemical concentration is high. Conversely, if the influent water quality is good or the chemical concentration is low, the sludge return ratio can be appropriately reduced, thereby reducing construction and operating costs.

[0039] The pilot-scale system of the high-density quick-sand sedimentation tank disclosed herein can be used to simulate the operation of the high-density quick-sand sedimentation tank, and can also be used to test the operating effect of the high-density quick-sand sedimentation tank under various parameters, thereby optimizing the operating parameters.

[0040] It should be noted that the content described below regarding the pilot-scale system of a high-density quicksand sedimentation tank can also be applied to high-density quicksand sedimentation tanks, and similarly, the content described for high-density quicksand sedimentation tanks can also be applied to the pilot-scale system of high-density quicksand sedimentation tanks. The pilot-scale system of a high-density quicksand sedimentation tank can also be referred to as a high-density quicksand sedimentation tank.

[0041] like Figure 1 As shown, the pilot-scale system 100 of the high-density quicksand sedimentation tank of this disclosure includes an equalization zone 1, a mixing zone 2, a dosing zone 3, a flocculation zone 4, a sedimentation zone 5, a sludge return device 6, and a dosing device 7. Furthermore, the pilot-scale system 100 of the high-density quicksand sedimentation tank of this disclosure may also include a buffer device 8. Each of the above zones may also be referred to as a part or system. The high-density quicksand sedimentation tank of this disclosure has a high upward flow velocity; depending on different treatment objectives, the upward flow velocity in each zone can reach up to 60 to 140 m / h.

[0042] Conditioning zone 1 receives the fluid to be processed, such as... Figure 1The system is designed to "intake water" and allows for flow regulation of the fluid within the regulating zone 1. The regulating zone 1 can also be called the inlet water system. For example, the regulating zone 1 may include a regulating tank 20, an inlet water pump 23, and an electromagnetic flow meter 24. For instance, the inlet water pump 23 and the electromagnetic flow meter 24 are sequentially installed on the output pipe of the regulating tank 20. The inlet water system needs to have an on / off function to ensure that the high-density rapid flow tank is isolated from external systems when the equipment is idle, under maintenance, or undergoing repairs. The electromagnetic flow meter 24 is used to record the treated water volume. If multiple high-density rapid flow tanks share a single inlet water system, the system also needs to have a flow distribution function to rationally allocate the required flow rate to each high-density rapid flow tank according to their treatment needs.

[0043] Mixing zone 2 is in fluid communication with regulating zone 1 to receive fluid from regulating zone 1 and to perform coagulation treatment on the fluid therein. Coagulants or other chemical agents can be added in the mixing zone. Under the action of the variable frequency mixer 21 installed in mixing zone 2, the coagulant or other chemical agents are fully mixed with the influent water and coagulate with various pollutants in the raw water to form fine, stable, and precipitable flocs called "lumps".

[0044] The dosing zone 3 is fluidly connected to the mixing zone 2 to receive fluid from the mixing zone 2, and a loading medium can be added to the fluid therein. For example, an appropriate amount of polymeric flocculant can be added to the dosing zone 3. Through the adsorption, entrainment, and bridging effects of the flocculant, it continuously forms larger flocs with the "flocs" formed in the mixing zone 2. Additionally, a loading medium can be added to the dosing zone 3. Under the action of a variable frequency mixer 31 installed in the dosing zone 3, the loading medium combines with the flocs to form larger and more stable "flocs". For example, the loading medium can be micron-sized fine sand. For example, the dosage of the loading medium can be flexibly adjusted as needed. For example, the loading medium in the system can have the following characteristics: true density = 3.8 to 4.1 g / cm³. 3 Bulk density = 2.2 g / cm³ 3 Particle size = 70 to 100 mesh.

[0045] The flocculation zone 4 is fluidly connected to the addition zone 3 to receive fluid from the addition zone 3 and to perform flocculation treatment on the fluid therein. For example, an appropriate amount of polymeric flocculant can be added to the flocculation zone 4. Under the action of the variable frequency mixer 41 installed in the flocculation zone 4, the loading medium and the "floc" continue to combine, improving the flocculation effect. Due to the presence of the loading medium, compared with the traditional sedimentation process, the flocs combined with the loading medium (hereinafter referred to as: loaded flocs) have greater density, settling properties, and stability. For example, the variable frequency mixer 41 can be a slow-speed mixer.

[0046] The sedimentation zone 5 is fluidly connected to the flocculation zone 4 to receive fluid from the flocculation zone 4, and to perform sedimentation treatment on the fluid therein to form a sludge mixture. The sedimentation zone 5 includes an upper clarification zone 51. An inclined tube module is installed in the clarification zone 51 to separate floc from water. An outlet device 53, i.e., an outlet weir 53, is installed above the inclined tube module. Specifically, the loaded flocs formed in the flocculation zone have a large entry area and slow down when flowing through the unstirred sedimentation zone 5. Under the influence of gravity, the loaded flocs settle to the bottom of the sedimentation zone before entering the inclined tube module, while the clear water flows upward through the inclined tube outlet of the inclined tube module, is collected by the outlet device 53 at the top of the sedimentation zone 5, and transported to the outside, such as... Figure 1 The "effluent" is shown in the diagram. Through shallow sedimentation in the inclined tubes, a small portion of the suspended solids carried by the water flow are also trapped within the inclined tubes. Due to the reasonable spacing and smoothness of the inclined tubes, the flocs entering the inclined tube module will quickly settle without causing blockage, further ensuring a lower suspended solids content in the effluent. In sedimentation zone 5, the loaded flocs settle down, forming a sludge mixture, such as a sand-sludge mixture, which accumulates at the bottom of the sedimentation zone. For example, the hydraulic loading of clarification zone 51 can be 60 to 140 m³ / h, preferably 60 to 75 m³ / h, and more preferably 60 to 70 m³ / h.

[0047] The sludge return device 6 is in fluid communication with the bottom of the sedimentation zone 5 to receive the sludge mixture from the sedimentation zone 5, and is configured to process the sludge mixture to form sludge and recycled fluid, and to transport the recycled fluid to the addition zone 3. For example, the sludge return device 6 includes a sludge return pump 61 and a hydrocyclone 64, which are installed on the return pipeline. The sludge return pump 61 draws the sludge mixture from the bottom of the sedimentation zone 5 back to the addition zone 3, and the hydrocyclone 64 separates the fluid and sludge. The loading medium can be present in the generated recycled fluid. For example, the loading medium is returned to the addition zone 3 from the bottom of the hydrocyclone 64, completing the recovery of the loading medium and realizing its recycling; the sludge flows from the top of the hydrocyclone 64 to the external sludge treatment unit 200 for further processing. An electromagnetic flowmeter 62 and a pressure gauge 63 are also installed on the return pipeline of the sludge return device 6 to record the return flow rate and operating pressure, respectively. A backwash water interface 65 is also provided on the return pipeline for flushing when sludge clogs the return pipeline; it is generally located upstream of the sludge return pump 61. The recovery of the loading medium improves its utilization rate, which can reduce costs.

[0048] The dosing device 7 is configured to dispense corresponding agents into the mixing zone 2, the dosing zone 3, and the flocculation zone 4, respectively. For example, the dosing device 7 may include multiple first pipes, such as 71, 72, and 73, leading to each of the aforementioned zones. The dosing device 7 may also include a pump assembly 74, which consists of... Figure 1 The P in the diagram represents the formation of multiple pumps. For example... Figure 1 As indicated by the middle arrow, the dosing device 7 can add coagulant to mixing zone 2, flocculant to dosing zone 3, and flocculant to flocculation zone 4. Depending on the required pH value for the reaction, the dosing device 7 can also add acid or alkali to mixing zone 2 to adjust to the optimal reaction pH. Furthermore, the dosing device 7 can supply service water to each of the first pipelines to adjust the concentration of the reagents. Although not shown in the figure, the dosing device 7 can add a loading medium to dosing zone 3. The dosing device 7 is configured to adjust the amount of loading medium added to dosing zone 3, for example, as needed, which improves system flexibility.

[0049] For example, the first pipe 71 of the dosing device 7 leads to the upper part of the dosing zone 3, the first pipe 72 of the dosing device 7 leads to the lower part of the flocculation zone 4, and the first pipe 73 of the dosing device 7 leads to the buffer device 8. By setting different flocculant dosing points, the influence of different dosing points on the reaction effect can be studied.

[0050] For example, the dosing zone 3 is fluidly connected to the flocculation zone 4 via a second pipe 32. The second pipe may be located at the bottom of the dosing zone 3. For example, the flow rate of the fluid in the second pipe 32 may be set to 0.84 m / s. For example, the concentration of the loading medium in the flocculation zone 4 may be maintained at 2 to 10 g / L.

[0051] Buffer device 8 is in fluid communication with sludge return device 6 to receive the recycled fluid and is configured to transport the recycled fluid to dosing zone 3. For example, buffer device 8 is positioned above dosing zone 3, and its bottom is in fluid communication with dosing zone 3. For example, buffer device 8 is in fluid communication with hydrocyclone 64, specifically, the outlet of hydrocyclone 64 leads to buffer device 8. For example, buffer device 8 can be a buffer tank. The buffer device prevents the impact of fluid from sludge return device on the fluid present in the tank. By positioning the buffer device directly above dosing zone 3, the recycled fluid can flow to the dosing zone by gravity, saving energy and resulting in a compact overall structure.

[0052] For example, the sludge return device 6 includes at least two sets of detachable hydrocyclones 64, the outlets of which are in fluid communication with the buffer device 8. For example, each set of hydrocyclones 64 may include only one hydrocyclone 64. Figure 1The pilot-scale system features two detachable hydrocyclones 64. Operation can be switched between at least two detachable hydrocyclones 64 as needed for testing, enhancing system flexibility. The detachable design allows operators to quickly replace components at different locations within the hydrocyclones. This flexibility enables the pilot-scale system to measure and analyze the separation effect of sludge containing the loading medium under varying hydrocyclone conditions, thereby optimizing the hydrocyclone operating parameters.

[0053] As mentioned above, each of the mixing zone 2, dosing zone 3, and flocculation zone 4 is equipped with a mixer, each of which has... Figure 1 The motor, represented by M, employs variable frequency control technology to adjust the rotational speed of the agitator blades. For example, the variable frequency agitator 41 in flocculation zone 4 is a double-layer variable frequency agitator, which can be used to enhance the mixing effect of the loaded flocs and prevent the loaded medium from depositing at the bottom of the flocculation zone. Therefore, in the pilot-scale system of this disclosure, flocculation zone 4 can achieve a good mixing effect without the need for a guide tube.

[0054] For example, mixing zone 2, dosing zone 3, flocculation zone 4, and sedimentation zone 5 are located in the same tank 101, such as... Figures 1 to 4 As shown, tank 101 can also be called a high-density sedimentation tank for rapid sand. In addition, mixing zone 2, dosing zone 3, flocculation zone 4 and sedimentation zone 5 are separated by corresponding partition walls 22.

[0055] Mixing zone 2, dosing zone 3, flocculation zone 4, and sedimentation zone 5 can be different parts of tank 101 connected in series in one direction. For example, mixing zone 2 has a first depth, dosing zone 3 has a second depth equal to the first depth, flocculation zone 4 has a third depth greater than the second depth, and sedimentation zone 5 has a fourth depth equal to the third depth. The depth difference between dosing zone 2 and flocculation zone 4 facilitates fluid flow from the dosing zone to the flocculation zone. A second conduit 32 connects or links the bottom wall of dosing zone 3 to the side wall of flocculation zone 4. For example, an opening is made in the bottom wall of dosing zone 2, which connects to the aforementioned second conduit.

[0056] For example, the sedimentation zone 5 also includes a sludge hopper zone 52 located below the clarification zone 51, the sludge hopper zone 52 having a funnel shape that tapers towards the bottom of the sludge hopper zone. For example, the sidewalls of the sludge hopper zone 52 may be inclined to form... Figures 1 to 3 The trumpet shape in [the context]. For example, in [the context of something like...] Figure 4 In the sedimentation zone 5 of the partially rectangular cross-section shown, the four side walls of the sludge hopper can all be inclined to form... Figures 1 to 3The sludge hopper 52 is shown in a flared shape that tapers towards the bottom. For example, the inclination angle of the sidewall of the sludge hopper 52 can be 60°. By providing a flared shape for the sludge hopper 52 that tapers towards the bottom, the sludge formed with the loaded flocs can slide downwards under its own gravity, and thus be drawn by the sludge return pump 61 and returned to the hydrocyclone 64. Compared with other designs, this disclosure does not require the use of a bottom scraper. In addition, the caking of bottom sludge and the formation of "channeling" phenomena can be avoided. This configuration allows the sludge return pump to more effectively extract bottom sludge, improving sludge return efficiency.

[0057] like Figure 1 As indicated by the arrows, the fluid to be treated, after passing through the equalization tank 30 in the equalization zone 1, is lifted by the inlet pump 23 at a constant flow rate and then flows to tank 101, i.e., the rapid sand high-density sedimentation tank. Within the rapid sand high-density sedimentation tank, the fluid sequentially flows through the mixing zone 2, the dosing zone 3, and the flocculation zone 4. The hydraulic retention time in each of these reaction tanks is 1.5 to 3 minutes. The fluid reacts with the coagulant, the loading medium, and the flocculant, respectively. The loading medium, coagulant, and flocculant form large and dense loading flocs in the flocculation zone 4. Figure 1 As indicated by the arrow in the middle tank 101, the fluid flows from the top of the partition wall 22 between the mixing zone 2 and the dosing zone 3 to the dosing zone 3, from the bottom of the partition wall 22 between the dosing zone 3 and the flocculation zone 4 to the flocculation zone 4 through the second pipe, and from the top of the partition wall 22 between the flocculation zone 4 and the sedimentation zone 5 to the sedimentation zone 5.

[0058] After the fluid passes through flocculation zone 4, the sludge formed with the loaded flocs enters sludge hopper zone 52, while the clarified effluent passes through the inclined tube module of clarification zone 51 and is finally discharged from the top effluent device 53, completing the removal of suspended solids and target pollutants. For example, the concentration of the loading medium in flocculation zone 4 can be maintained at 2 to 10 g / L, the hydraulic load of clarification zone 51 can be 60 to 75 m / h, the water depth on the weir (i.e., partition wall) from flocculation zone 4 to sedimentation zone 5 can be 0.1 m, and the fluid velocity can be 167 m / h. The inclined tube module of clarification zone 51 is based on the principle of shallow sedimentation to further clarify the small flocs in the fluid or water. For example, the diameter of the inclined tube can be 30 to 35 mm, the length can be 500 mm, and the inclination angle can be 60°.

[0059] After separation by the hydrocyclone, the loading medium returns to the buffer device 8 through the bottom of the hydrocyclone 64 in the sludge return device 6, and then returns to the dosing zone 3 by gravity. The sludge is discharged from the top of the hydrocyclone 64 and sent to the external sludge treatment unit 200, with a sludge concentration of approximately 3 to 6 g / L. An additional sludge return pipeline can also be installed on the return pipeline of the sludge return device 6, thus allowing for simultaneous loading medium recovery and sludge return (e.g., return to the dosing zone 3). The sludge return pump 61 uses frequency conversion control to adjust the sludge return flow rate, and thus the sludge return ratio can be adjusted as needed. The ratio of the sludge return flow rate to the influent flow rate is called the sludge return ratio, which is typically set to 8 to 15%.

[0060] like Figure 2 As shown, for example, observation window 9 is provided in flocculation zone 4, and observation window 10 is provided in clarification zone 51. Specifically, observation window 9 is provided at the bottom of flocculation zone 4, and observation window 10 is provided at the bottom of clarification zone 51. For example, tempered glass is installed in observation windows 9 and 10 respectively. Through the observation windows, operators can directly observe the formation of the loaded flocs in flocculation zone 4 and the sludge level at the bottom of sedimentation zone 5, thereby directly understanding the operating status of the high-density quick-sand sedimentation tank. For example, the distance between observation windows 9 and 10 and the bottom of the corresponding area can be 150 to 200 mm to facilitate observation by operators.

[0061] like Figure 2 As shown, for example, the pilot-scale system also includes multiple sampling ports 11, 12, 13, 14, 15, 16, 17, 18, and 19. These sampling ports are used to collect fluid or water samples to determine the levels of target pollutants at the equipment's inlet and outlet. Sampling port 11 is located at the inlet, and sampling port 16 is located at the outlet. Sampling port 12 is located within the mixing zone 2, specifically near the corresponding partition wall 22. Sampling port 13 is located at the bottom of the dosing zone 3. Sampling port 14 is located within the flocculation zone 4, specifically at the top of the zone. Sampling port 15 is located at the bottom of the clarification zone 51. Sampling port 17 is located on the return pipeline of the sludge return device 6. Sampling port 18 is located at the bottom of the hydrocyclone 64. Sampling port 19 is located in the overflow area at the top of the hydrocyclone 64. The above-mentioned sampling ports, set in different locations, can be used to collect fluid or water samples from different areas. For example, they can be used to measure the concentration of the loading medium in each area and to detect the operating status of the high-density sedimentation tank.

[0062] like Figure 3As shown, for example, the pilot-scale system also includes multiple first weir plates 25, each with an adjustable height and respectively disposed on top of a corresponding partition wall 22. For example, a first weir plate 25 is installed on top of each partition wall 22. The first weir plates are used to adjust the liquid level in the tank 101 according to different influent flow rates to maintain a uniform distribution of water flow in the high-density sedimentation tank and ensure stable liquid level.

[0063] For example, the pilot-scale system also includes a second weir plate 26, which has an adjustable height and is mounted on the effluent device 53 in the clarification zone 51. For example, two second weir plates 26 may be mounted on the effluent device 53. The second weir plates allow for control of the effluent flow rate under different reaction conditions, ensuring effluent quality.

[0064] like Figure 3 As shown, for example, the bottom of the dosing zone 3 and the flocculation zone 4 is provided with inclined plates 27 extending from their sidewalls to their bottom walls. In other examples, it is also possible to provide an inclined plate at the bottom of one of the dosing zone 3 and the flocculation zone 4. For example, an inclined plate 27 is provided between each sidewall and the bottom wall of the dosing zone 3, and the same is true for the flocculation zone 4. This construction can prevent the loading medium from accumulating at the bottom of the tank and forming a "dead zone" that is difficult to stir and mix, and helps to promote the uniform distribution and mixing of the loading medium.

[0065] See you again Figure 1 and Figure 3 The bottom of the funnel-shaped sludge hopper area 52 is provided with a sludge return port 54, and the return pipeline of the sludge return device 6 is connected to the sludge return port 54.

[0066] like Figure 4 As shown in the top view, for example, the hydrocyclone 64 is located above the dosing zone 3. The remainder of the sludge return device 6, excluding the hydrocyclone 64, is at least partially disposed on one side of at least one of the dosing zone 3, the flocculation zone 4, and the sedimentation zone 5. For example, the remainder of the sludge return device 6, excluding the hydrocyclone 64, is disposed on one side of the dosing zone 3, the flocculation zone 4, and the sedimentation zone 5, and is installed parallel to each of the aforementioned zones. Figure 4 The diagram also shows the effluent storage area 102 located at the outlet of sedimentation zone 5 and the ladder 103 located on the other side of flocculation zone 4. Through a rational arrangement of functional zones, the length of the pilot-scale system of the high-density quick-sand sedimentation tank is ensured to not exceed 4 m and the width to not exceed 2 m. This design allows for fully integrated assembly of the system in the factory, enabling transportation to the test site by conventional trucks without additional installation work, ensuring rapid start-up of the pilot-scale system. Furthermore, this layout ensures that the functional zones are compact, rationally sized, and appropriately sized, guaranteeing both the integrity of the process flow and ease of operation and maintenance.

[0067] For example, Table 1 below shows the treatment effects on turbidity and fluoride in the fluid obtained by the pilot system of the high-density quick-sand sedimentation tank of this disclosure using the following basic operating parameters: the hydraulic load of the inclined tube module in the clarification zone 51 is 60 m / h, the concentration of the loading medium is maintained at 4 g / L, the dosage of polyaluminum chloride as coagulant is 70 mg / L (calculated based on aluminum content), the dosage of polyacrylamide as flocculant is 3 mg / L (based on commercial powder), and the sludge return ratio is set at 15%.

[0068] Table 1

[0069]

[0070] Turbidity can be considered an indicator of suspended pollutants, while fluoride can be considered an indicator of dissolved pollutants. As shown in Table 1, the pilot-scale system of the high-density quick-sand sedimentation tank of this disclosure achieved turbidity removal rates of 90% and fluoride removal rates of 70-80%. This indicates that the pilot-scale system of the high-density quick-sand sedimentation tank of this disclosure has excellent treatment effects on the target pollutants.

[0071] As described above, the parameters of each part in the pilot-scale system of the high-density quick-sand sedimentation tank of this disclosure are all configurable. Therefore, it can simulate the feasibility of the high-density quick-sand sedimentation tank process for treating target water bodies, guiding the process design of actual projects. It can also be used to establish the relationship between different operating parameters and treatment effects, guiding actual production operation. In addition, the pilot-scale system of the high-density quick-sand sedimentation tank of this disclosure optimizes sludge discharge and reagent dosing, and improves the utilization rate of the loading medium by recovering the loading medium. Furthermore, the pilot-scale system of the high-density quick-sand sedimentation tank of this disclosure does not use bulky scrapers and guide tubes, and rationally sets up the remaining parts of the hydrocyclone and sludge return device, thus achieving a high degree of integration, compact structure, and ease of movement.

[0072] Furthermore, the technical features disclosed above are not limited to the combinations of the disclosed features with other features. Those skilled in the art can also make other combinations of the technical features according to the purpose of the disclosure in order to achieve the purpose of this disclosure.

Claims

1. A pilot system of a rapid sand high-density sedimentation tank, characterized by, The pilot-scale system (100) includes: The regulating zone (1) receives the fluid to be processed and allows for flow rate regulation of the fluid therein; The mixing zone (2) is in fluid communication with the regulating zone to receive fluid from the regulating zone and to perform coagulation treatment on the fluid therein; The dosing zone (3) is in fluid communication with the mixing zone to receive fluid from the mixing zone and to dispense a loading medium into the fluid therein; Flocculation zone (4) is in fluid communication with the dosing zone to receive fluid from the dosing zone and to perform flocculation treatment on the fluid therein; The sedimentation zone (5) is in fluid communication with the flocculation zone to receive fluid from the flocculation zone and to perform sedimentation treatment on the fluid therein to form a sludge mixture. The sludge return device (6) is in fluid communication with the bottom of the sedimentation zone to receive the sludge mixture from the sedimentation zone, and is configured to process the sludge mixture to form sludge and recover fluid. The dosing device (7) is configured to dispense corresponding agents into the mixing zone, the dosing zone, and the flocculation zone, respectively; and The buffer device (8) is in fluid communication with the sludge return device to receive the recycled fluid and is configured to deliver the recycled fluid to the dosing zone (3).

2. The pilot system according to claim 1, characterized in that, The buffer device (8) is disposed above the dosing area (3), and its bottom is in fluid communication with the dosing area.

3. The pilot system of claim 1, wherein, The dosing device (7) has a plurality of first pipes (71, 72, 73) respectively leading to the upper part of the dosing zone, the buffer device, and the bottom of the flocculation zone.

4. The pilot system of claim 1, wherein, The dosing device (7) is configured to adjust the amount of loading medium dispensed into the dosing zone (3).

5. The pilot system of claim 1, wherein, The dosing zone (3) is in fluid communication with the flocculation zone (4) through the second pipe (32).

6. The pilot system of claim 5, wherein, The depth of the flocculation zone (4) is greater than the depth of the dosing zone (3), and the second pipe (32) connects the bottom wall of the dosing zone (3) with the side wall of the flocculation zone (4).

7. The pilot system of claim 1, wherein, Each of the mixing zone (2), the addition zone (3), and the flocculation zone (4) is equipped with a variable frequency mixer (21, 31, 41), wherein the variable frequency mixer in the flocculation zone (4) is a double-layer variable frequency mixer.

8. The pilot system of claim 1, wherein, The sedimentation zone (5) includes a clarification zone (51) and a mud hopper zone (52), the mud hopper zone being located below the clarification zone and having a funnel shape that tapers toward the bottom of the mud hopper zone.

9. The pilot system according to claim 8, characterized in that, The flocculation zone (4) and the clarification zone (51) are each provided with observation windows (9, 10).

10. The pilot system of claim 1, wherein, The pilot-scale system also includes multiple sampling ports (11, 12, 13, 14, 15, 16, 17, 18, 19).

11. The pilot system of claim 8, wherein, The mixing zone (2), the dosing zone (3), the flocculation zone (4), and the sedimentation zone (5) are located in the same tank (101) and separated by corresponding partition walls (22). The pilot-scale system also includes multiple first weir plates (25), each of which has an adjustable height and is respectively set on the top of the corresponding partition wall.

12. The pilot system of claim 11, wherein, The pilot system also includes a second weir plate (26), which has an adjustable height and is mounted on the effluent device (53) in the clarification zone (51).

13. The pilot system of claim 1, wherein, The bottom of the dosing zone (3) and / or the flocculation zone (4) is provided with an inclined plate (27) extending from its sidewall to its bottomwall.

14. The pilot system of claim 1, wherein, The sludge return device (6) includes at least two sets of detachable hydrocyclones (64), the outlets of which are in fluid communication with the buffer device (8).

15. The pilot system of claim 14, wherein, The hydrocyclone (64) is located above the dosing zone (3).

16. The pilot system of claim 15, wherein, The remaining portion of the sludge return device (6), excluding the hydrocyclone (64), is at least partially disposed on one side of at least one of the addition zone (3), the flocculation zone (4), and the sedimentation zone (5).

17. The pilot system of claim 16, wherein, The length of the pilot system shall not exceed 4 m and the width shall not exceed 2 m.

18. The pilot system of claim 1, wherein, The sludge return device (6) includes a variable frequency pump.

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