An efficient sedimentation system for industrial water plants

Abstract

The present invention discloses an efficient sedimentation system for an industrial water plant. The sedimentation area is arranged in three layers. Perforated pipes are respectively connected above the ends of each layer of the sedimentation area to form an effluent area. An effluent well is provided behind the effluent area, and the effluent well communicates with all the perforated pipes of each layer of sedimentation tank, ensuring that the water level in the effluent well is at least 20 cm higher than the top of the highest perforated pipe. The ends of the three-layer sedimentation area are completely isolated, so that the water flow between the three-layer sedimentation areas cannot affect each other, thereby improving the overall sedimentation effect of the flocs in the sedimentation area. By setting an independent effluent system, the present invention realizes the complete closure of each layer of sedimentation tank, avoids the mutual interference of the water flow in each layer of sedimentation tank, and improves the treatment effect and operation stability of the three-layer horizontal flow sedimentation tank. By using the independent submerged effluent of each layer, the same effluent pressure difference can be achieved, ensuring the same flow rate in each layer of sedimentation tank and avoiding the adverse situation of uneven flow rate in each layer of sedimentation tank caused by short circuit.

Description

Technical Field

[0001] The present invention relates to an efficient sedimentation system for industrial water plants. This tank type is mainly applied in the sedimentation process of water treatment. By setting three sedimentation zones in parallel up and down, the sedimentation efficiency is improved and the floor area is saved. Background Art

[0002] Industrial water plants have relatively low requirements for water quality (except for special industries), but have relatively high requirements for the cost of water purification treatment. Therefore, it is very necessary to use efficient treatment processes to deal with industrial water treatment. The horizontal flow sedimentation tank is one of the common tank types in water treatment plants. The horizontal flow sedimentation tank has a simple structure, convenient operation and management, strong adaptability to changes in water quality and water volume, and a high guarantee rate of effluent water quality. It is one of the sedimentation tank types with the best recognized stability and is especially suitable for industrial water plants. However, the horizontal flow sedimentation tank also has disadvantages, such as a large floor area. Usually, the floor area of the horizontal flow sedimentation tank is several times that of the inclined tube sedimentation tank, and the urban construction land index is usually very tight. Therefore, this greatly limits the popularization and use of the horizontal flow sedimentation tank.

[0003] In view of the problem of the large floor area of the horizontal flow sedimentation tank, three-layer horizontal flow sedimentation tanks are used in some projects. The three-layer horizontal flow sedimentation tank can improve the sedimentation efficiency and reduce the floor area, but the actual operation effect after completion is unsatisfactory. This is because the water inlet and outlet methods and sludge discharge methods of the three-layer horizontal flow sedimentation tank are very different from those of ordinary single-layer horizontal flow sedimentation tanks, and these detailed designs are prone to problems, thus affecting the sedimentation effect during operation and ultimately resulting in unstable effluent water quality of the sedimentation tank. This is essentially caused by the inertial thinking of using a single-layer sedimentation tank to design a three-layer sedimentation tank. Therefore, how to discover and solve these design defects has become the key to overcoming the operation stability of the three-layer sedimentation tank.

[0004] Traditional three-layer horizontal flow sedimentation tanks are mainly divided into two categories: series and parallel. In series, the raw water usually enters through one side of the lower sedimentation tank, changes the water flow direction from the other side of the lower sedimentation tank, enters the upper sedimentation tank, and finally exits through the upper sedimentation tank. In parallel, the raw water is usually evenly distributed to the upper and lower sedimentation tanks, and the water flows to the end and then exits through the water surface outlet trough or outlet pipe uniformly. Whether in series or parallel, traditional three-layer horizontal flow sedimentation tanks cannot avoid using the water surface outlet method, resulting in mutual disturbance in each sedimentation tank and affecting the sedimentation effect of flocs.

[0005] Moreover, since filters are usually not installed after the sedimentation tank in industrial water treatment, changes in the influent water quality and water volume will cause unstable effluent water quality. Traditional horizontal flow sedimentation tanks cannot control the influent water volume according to the water quality upstream of the sedimentation zone and cannot guarantee the safety of the effluent water quality.

[0006] To solve this problem, it is necessary to study an efficient sedimentation system for industrial water plants. By completely changing the sedimentation method and the inlet and outlet water methods of the horizontal flow sedimentation tank, the design defects of the existing three-layer horizontal flow sedimentation tank are solved, so as to fundamentally improve the treatment effect and operation stability of the three-layer horizontal flow sedimentation tank. Summary of the Invention

[0007] The purpose of the present invention is to provide an efficient sedimentation system for industrial water plants, which improves the treatment effect and operation stability of the three-layer horizontal flow sedimentation tank by optimizing the sedimentation method and the inlet and outlet water methods of the sedimentation tank.

[0008] To achieve the above purpose, the technical solution of the present invention is: an efficient sedimentation system for industrial water plants, including an inlet mixing area, a flocculation area, a water distribution area, and a sedimentation area arranged in sequence. The inlet mixing area is connected to an inlet pipe, and an inlet valve is provided on the inlet pipe. It is characterized in that the sedimentation area is arranged in three layers, and perforated pipes are respectively connected above the ends of each layer of the sedimentation area to form an outlet area. An outlet well is provided behind the outlet area, and the outlet well communicates with all the perforated pipes of each layer of the sedimentation tank to ensure that the water level in the outlet well is at least 20 cm higher than the top of the highest perforated pipe. The ends of the three-layer sedimentation area are completely isolated, and sampling points are arranged below the water surface of the upper sedimentation area to control the opening degree of the inlet valve by detecting the turbidity of the water at the sampling points, so as to adjust the inlet water volume.

[0009] Further, the water depth of each layer of the sedimentation tank is 2.5 - 3.5 m, each layer of the sedimentation tank includes several single-cell sedimentation tanks, the width of the single-cell sedimentation tank is 8 - 12 m, and the length is 40 - 60 m.

[0010] Further, an outlet weir is arranged in the outlet well, and an outlet channel is connected behind the outlet weir. A mixer is arranged before the outlet channel to improve the treatment effect of subsequent treatment structures through the micro-flocculation process.

[0011] Further, the opening diameter of the perforated pipe is 20 mm to 30 mm, with double-sided openings, the opening spacing is 10 cm to 30 cm, and the opening angle is inclined upward at an angle α with the horizontal direction, where α is 0 degree to 45 degrees.

[0012] Further, the flocculation area adopts a grid flocculation tank, and the water distribution area adopts a perforated flower wall to achieve the uniformity of water distribution.

[0013] Further, four sampling points are arranged at different intervals 1.0 m below the water surface of the upper sedimentation area. The four sampling points are respectively located at 10 minutes, 20 minutes, 30 minutes, and 60 minutes of sedimentation time, and are successively called the 1st sampling point, the 2nd sampling point, the 3rd sampling point, and the 4th sampling point; the opening degree of the inlet valve is controlled by detecting the turbidity of the water at the sampling points, so as to adjust the inlet water volume, control the operation status of the sedimentation tank, and ensure the water quality of the outlet.

[0014] Further, when the turbidity at sampling point No. 1 is greater than 20NTU, the linkage regulating water inlet valve is closed until the turbidity at sampling point No. 1 is less than 15NTU, and the linkage regulating water inlet valve is reopened; when the turbidity at sampling point No. 2 is greater than 10NTU, the linkage regulating water inlet valve is closed until the turbidity at sampling point No. 2 is less than 6NTU, and the linkage regulating water inlet valve is reopened; when the turbidity at sampling point No. 3 is greater than 5NTU, the linkage regulating water inlet valve is closed until the turbidity at sampling point No. 3 is less than 3NTU, and the linkage regulating water inlet valve is reopened; when the turbidity at sampling point No. 4 is greater than 3NTU, the linkage regulating water inlet valve is closed until the turbidity at sampling point No. 4 is less than 2NTU, and the linkage regulating water inlet valve is reopened.

[0015] The three-layer horizontal flow sedimentation tank of the high-efficiency sedimentation system of the industrial water plant of the present invention can realize the complete isolation of each layer of horizontal flow sedimentation tank in the sedimentation area and the water outlet area, avoid mutual influence during the operation of each area, and improve the overall water outlet effect. This completely independent water outlet system can realize the completely independent operation of each layer of sedimentation tank. Its main function is to use perforated pipes to discharge water from each layer of sedimentation tank. After the water outlet pipe, a water outlet weir is set to make the water outlet pressure of the perforated pipes of each layer of sedimentation tank the same, so as to achieve the same water volume in and out of each layer of sedimentation tank, and avoid the uneven water distribution caused by short flow in the parallel three-layer horizontal flow sedimentation tank with uniform water outlet on the water surface. This three-layer horizontal flow sedimentation tank can save half of the floor space compared with ordinary horizontal flow sedimentation tanks, optimize the flow state at the outlet trough or outlet pipe compared with the parallel three-layer horizontal flow sedimentation tank with uniform water outlet on the water surface, and improve the water quality of the outlet water. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is the upper floor plan of a high-efficiency sedimentation system for an industrial water plant.

[0017] Figure 2 This is a plan view of the lower level of an industrial water plant's high-efficiency sedimentation system.

[0018] Figure 3 This is an AA cross-section diagram of a high-efficiency sedimentation system in an industrial water plant.

[0019] Figure 4 This is a BB cross-section diagram of a high-efficiency sedimentation system in an industrial water plant.

[0020] Figure 5 This is a cross-sectional view of a high-efficiency sedimentation system CC in an industrial water plant. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0022] This embodiment of the present invention is an efficient sedimentation system for industrial water plants, which mainly includes an influent mixing zone, a flocculation zone, a water distribution zone, a sedimentation zone, an effluent zone, etc. The influent is introduced through pipelines, and the added coagulant is uniformly mixed with the raw water through a pipeline mixer. Mechanical mixing with stirring paddles can also be used. The grid flocculation process is adopted in the flocculation zone, and other hydraulic flocculation processes such as the folded plate flocculation process can also be used. The perforated flower wall is used in the water distribution zone, and natural water distribution without facilities can also be adopted. The sedimentation zone adopts a multi-layer sedimentation zone that is completely enclosed at the end, which can ensure that the water flow in each sedimentation layer operates completely independently and avoids mutual influence. The effluent zone adopts submerged perforated pipes for effluent, and an effluent well is set at the outlet, leading to subsequent treatment structures finally.

[0023] As shown in the figure, the novel three-layer horizontal flow sedimentation tank of the present invention mainly realizes the complete independence of each sedimentation area through the independent effluent system of each layer of sedimentation tank, avoiding the mutual influence during the operation of each layer of sedimentation tank.

[0024] The influent mixing zone 1 is mainly composed of an influent pipe and a mixing device, and its main function is to mix the influent and the coagulant. Among them, the influent pipe is usually provided with pipe fittings such as maintenance valves, and the pipe diameter is determined according to the water volume, usually DN800~DN1200, corresponding to the maximum daily water volume of about 25,000~100,000 m 3 / d. The mixing device can adopt a pipeline mixer as shown in the figure, or a mixing tank and a mechanical mixing device can be set separately.

[0025] The main purpose of the flocculation zone 2 is to improve the sedimentation performance of flocs by hydraulic or mechanical flocculation to make the flocs grow from small to large. As shown in the figure, a grid flocculation tank is adopted, and other hydraulic flocculation processes such as folded plate flocculation can also be used.

[0026] The method adopted in the water distribution zone 3 is mainly determined according to the effluent uniformity of the flocculation process. As shown in the figure, the grid flocculation process is adopted in the flocculation process, and the effluent is uneven, so a perforated flower wall is needed to achieve uniform water distribution. If the effluent of the flocculation process is relatively uniform, water distribution facilities may not be applicable, and the water can be naturally distributed to each sedimentation layer.

[0027] The sedimentation zone 4 is arranged in three layers, and the water depth of a single-layer sedimentation tank is 2.5~3.5m. The width of a single-cell sedimentation tank is usually 8~12m, and the length is 40~60m. The ends of the three-layer sedimentation zone are completely isolated, so that the water flow between the three-layer sedimentation zones cannot affect each other, thereby improving the overall sedimentation effect of the flocs in the sedimentation zone.

[0028] The perforated pipe 5 adopts a steel pipe or stainless steel pipe with a diameter of DN300~DN500, the opening diameter is 20mm to 30mm, with openings on both sides, the opening spacing is usually 10cm to 30cm, and the opening angle is inclined upward at an angle α with the horizontal direction, and α is 0 degree to 45 degrees.

[0029] The water outlet well 6 is connected to all the perforated pipes 5 of each layer of sedimentation tank, and it is ensured that the water level in the water outlet well is at least 20 cm higher than the top of the highest perforated pipe. The designed flow velocity in the water outlet well 6 is less than 0.5 m / s.

[0030] The water outlet channel 7 is connected to the water outlet well 6 to convey the effluent from the sedimentation tank to the next-stage treatment structure. A mixer can be set as shown in the figure before the water outlet channel to improve the treatment effect of the subsequent treatment structure through the micro-flocculation process.

[0031] The sampling points 8 are set 1.0 m below the water surface. The four sampling points are respectively located at the sedimentation times of 10 minutes, 20 minutes, 30 minutes, and 60 minutes (for sedimentation tanks with a total sedimentation time of 120 minutes), and are sequentially called Sampling Point 1, Sampling Point 2, Sampling Point 3, and Sampling Point 4. The operation condition of the sedimentation tank is judged and the effluent water quality is predicted by measuring the turbidity of the water at the sampling points. The effluent water quality is improved by automatically adjusting the inlet valve to reduce the inlet flow rate.

[0032] The linkage-adjusted inlet valve 9 can control the water inflow of the sedimentation tank through the switching degree, so as to control the effluent water quality.

[0033] It is different from the existing technology in that:

[0034] 1. Compared with the traditional three-layer horizontal flow sedimentation tank, the tank type of the present invention realizes the independent water outlet of each sedimentation area by using the perforated pipe for water outlet, avoiding the phenomena such as large floor area of the water outlet area and mixing of the water flows in each layer of sedimentation tank caused by the unified water outlet of the traditional three-layer horizontal flow sedimentation tank.

[0035] 2. Compared with the traditional three-layer horizontal flow sedimentation tank, the tank type of the present invention uses a water outlet weir to submerge the perforated pipes of each layer, ensuring that the water outlet pressure differences of the outlet pipes with different heights of each layer are the same, and the water outlet flow rates of each layer of sedimentation tank can be the same, avoiding the adverse phenomenon of uneven water volume of each layer caused by short circuit and other situations in the traditional horizontal flow sedimentation tank.

[0036] 3. Compared with the traditional three-layer horizontal flow sedimentation tank which has high requirements for the levelness of the water outlet weir, the tank type of the present invention has low requirements for the installation flatness of the submerged outlet pipes, and there will be no phenomenon of uneven water outlet of a single water outlet weir caused by inconsistent levelness of the water outlet weir.

[0037] 4. Compared with the traditional three-layer horizontal flow sedimentation tank, the tank type of the present invention has a smaller floor area and better effluent water quality.

[0038] 5. Since the water flow in the sedimentation tank is plug flow, the effluent water quality can be judged according to the turbidity of the water upstream of the sedimentation tank. If the detected turbidity is too high, the inlet flow rate can be reduced by automatically adjusting the inlet valve to improve the effluent water quality.

[0039] 5. Since the water flow in the sedimentation tank is plug flow, the effluent water quality can be judged according to the turbidity of the water upstream of the sedimentation tank. If the detected turbidity is too high, the inlet flow rate can be reduced by automatically adjusting the inlet valve to improve the effluent water quality.

[0040] 6. The control logic between the water turbidity at the sampling point and the inlet valve is as follows: When the turbidity at the No. 1 sampling point is greater than 20 NTU, the inlet valve 9 is linked and adjusted to close until the turbidity at the No. 1 sampling point is less than 15 NTU, and then the inlet valve 9 is linked and adjusted to reopen; When the turbidity at the No. 2 sampling point is greater than 10 NTU, the inlet valve 9 is linked and adjusted to close until the turbidity at the No. 2 sampling point is less than 6 NTU, and then the inlet valve 9 is linked and adjusted to reopen; When the turbidity at the No. 3 sampling point is greater than 5 NTU, the inlet valve 9 is linked and adjusted to close until the turbidity at the No. 3 sampling point is less than 3 NTU, and then the inlet valve 9 is linked and adjusted to reopen; When the turbidity at the No. 4 sampling point is greater than 3 NTU, the inlet valve 9 is linked and adjusted to close until the turbidity at the No. 4 sampling point is less than 2 NTU, and then the inlet valve 9 is linked and adjusted to reopen.

Claims

1. An efficient sedimentation system for an industrial water plant, comprising a water inlet mixing zone, a flocculation zone, a water distribution zone, and a sedimentation zone arranged in sequence. The water inlet mixing zone is connected to a water inlet pipe, and a water inlet valve is provided on the water inlet pipe. It is characterized in that The sedimentation area is arranged in three layers. Perforated pipes are connected to the top of the end of each sedimentation area to form a water outlet area. A water outlet well is set at the rear of the water outlet area. The water outlet well connects all the perforated pipes of each sedimentation area to ensure that the water level of the water outlet well is at least 20 cm higher than the top of the highest perforated pipe. The ends of the three sedimentation areas are completely isolated. Sampling points are set below the water surface of the upper sedimentation area to control the degree of opening and closing of the water inlet valve by detecting the turbidity of the water at the sampling point, thereby adjusting the water inlet volume. A water outlet weir is set in the water outlet well, and the rear of the water outlet weir is connected to the water outlet channel. A mixer is set before the water outlet channel to improve the treatment effect of the subsequent treatment structure through the micro-flocculation process. The total sedimentation time of the sedimentation area is 120 minutes. Four sampling points are set at different intervals of 1.0 m below the water surface of the upper sedimentation area. The four sampling points are located at 10 minutes, 20 minutes, 30 minutes and 60 minutes of sedimentation time, respectively, and are called sampling point No. 1, sampling point No. 2 and sampling point No.

3. No. 1 sampling point, sampling point 3, and sampling point 4; by detecting the turbidity of water at the sampling points to control the degree of opening and closing of the water inlet valve, the amount of water inlet is adjusted, the operation status of the sedimentation area is controlled, and the quality of the effluent water is guaranteed; when the turbidity of sampling point No. 1 is greater than 20NTU, the water inlet valve is closed by linkage adjustment until the turbidity of sampling point No. 1 is less than 15NTU, and the water inlet valve is reopened by linkage adjustment; when the turbidity of sampling point No. 2 is greater than 10NTU, the water inlet valve is closed by linkage adjustment until the turbidity of sampling point No. 2 is less than 6NTU, and the water inlet valve is reopened by linkage adjustment; when the turbidity of sampling point No. 3 is greater than 5NTU, the water inlet valve is closed by linkage adjustment until the turbidity of sampling point No. 3 is less than 3NTU, and the water inlet valve is reopened by linkage adjustment; when the turbidity of sampling point No. 4 is greater than 3NTU, the water inlet valve is closed by linkage adjustment until the turbidity of sampling point No. 4 is less than 2NTU, and the water inlet valve is reopened by linkage adjustment.

2. The high-efficiency sedimentation system of an industrial water plant according to claim 1, characterized in that The water depth of each sedimentation area is 2.5~3.5m. Each sedimentation area includes several single-cell sedimentation tanks. The width of a single-cell sedimentation tank is 8~12m and the length is 40~60m.

3. The high-efficiency sedimentation system for an industrial water plant according to claim 1, characterized in that The perforated pipe has an opening diameter of 20 mm to 30 mm, with openings on both sides and an opening spacing of 10 cm to 30 cm. The angle between the opening and the horizontal direction is α degrees obliquely upward, and α is 0 degrees to 45 degrees.

4. The high-efficiency sedimentation system of an industrial water plant according to claim 1, characterized in that The flocculation area adopts a grid flocculation tank, and the water distribution area adopts a perforated flower wall to achieve uniform water distribution.

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