Seawater pump room power back-flushing silt reduction system

Abstract

The utility model provides a seawater pump room power back-flushing silt reduction system, which is characterized in that a water taking flow channel is provided with a seawater pump for taking water, the water taking flow channel is connected with seawater through a forebay, back-flushing pipelines are arranged in the water taking flow channel and the forebay, and the back-flushing pipelines are connected with a factory water taking pipeline; backwash control valves are connected between the backwash pipelines and the plant area water taking pipeline, each backwash pipeline is provided with a plurality of backwash nozzles, the backwash nozzles on the two sides are distributed in a staggered mode in the horizontal direction, the distance between the backwash nozzles and the bottom of the water taking flow channel is 10-20 cm, and the backwash nozzles are duckbilled nozzles provided with flat water outlets. According to the system, an automatic control system is adopted, sediment at the bottom of a pump room is disturbed intermittently every day through high-speed nozzle outlet jet flow, on one hand, most of the sediment can be started and leave the pump room through a sea water pump, on the other hand, the sediment is disturbed, the overall sediment consolidation duration is broken, and the hardening process of the viscous sediment is delayed; and the difficulty of manual dredging work is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to the dredging of seawater pumping station, specifically relates to a seawater pumping station power backflushing silt reduction system. BACKGROUND

[0002] Generally, seawater pumping station facilities are equipped in liquefied natural gas plants, power plants and other plants. Different water intake processes exist according to different water intake facility arrangements, but generally, the seawater obtained is middle and lower layer seawater. With water flow movement, silt will inevitably enter the pumping station; at the same time, the space scale in the pumping station is large and the water flow velocity is small, which is easy to cause silt deposition and accumulation, which may cause the facilities in the pumping station to fail to work normally or even be damaged, so it is necessary to clean the silt accumulated at the bottom of the pumping station regularly.

[0003] The silt in the surrounding provinces and cities of the lower reaches of the Yangtze River, such as Jiangsu, Shanghai and Zhejiang, is mainly cohesive silt, and the sediment concentration of the water body on the shore is large. Among them, Shanghai LNG adopts the method of using high-pressure water gun to spray high-speed water flow to roll up the bottom deposited silt, and using a mobile sewage pump to discharge sewage to clean the silt accumulation. The advantage of this method is that the operation is simple, convenient and fast, but it also has the following problems:

[0004] ①The efficiency of cleaning silt accumulation is low, and the interval time between two times of dredging is generally long, and the long-term deposited silt is easy to be hardened and cannot be lifted by high-pressure water flow;

[0005] ②The dredging work needs manual operation, which increases the labor cost in the long run;

[0006] ③In order to ensure the safety of the staff, the work of the seawater pumping station needs to be suspended during the dredging operation, which reduces the production efficiency of the plant.

[0007] According to the principle of cohesive silt accumulation and the experience of related engineering examples, the difficulties of cohesive silt dredging operation mainly lie in the following problems:

[0008] ①Long-term accumulation will cause the consolidation of the accumulated body, which is difficult to be washed away by water flow and needs manual cleaning;

[0009] ②The dredging operation needs to stop the operation of the water pumping station, which affects the production efficiency;

[0010] ③The higher the frequency of dredging operation, the more the production efficiency is reduced; if the frequency of dredging operation is too low, the difficulty and workload of dredging are higher.

[0011] Therefore, the utility model will focus on improving the following aspects:

[0012] 1. Shorten the dredging interval to avoid the consolidation of the accumulated body;

[0013] 2. Automatic dredging measures to improve the dredging efficiency;

[0014] 3. Try to carry out dredging operation without affecting the normal production of the factory, reduce the loss of benefits.

[0015] According to the different regions and the nature of the water, the local sediment composition will also change, and the nature of the sediment in the pump house will also change. For seawater environment, generally can be considered that the particle diameter d≤0.03mm of the sediment is fine-grained sediment clayey sediment, which will occur flocculation phenomenon, the sediment in the pump house will occur hardening phenomenon; d>0.03mm of the sediment is coarse-grained sediment, which will not occur obvious flocculation phenomenon, the sediment in the pump house will not consolidate with time.

[0016] For the already accumulated clayey sediment, if not treated in time, the sediment will gradually consolidate and compact, and the water will gradually drain out, resulting in more difficult to be washed away; and the water intake pump house is one of the key links of the factory production facilities, which needs to be maintained for a long time. In the case of local sediment composition mainly being clayey sediment, the sediment in the bottom of the pump house will be more and more difficult to be washed away with time, and finally the dredging operation needs to be carried out.

[0017] The main variables related to the flushing of the consolidated sediment of clayey sediment are as follows:

[0018] 1) The smaller the particle size of the sediment, the smaller the flushing rate;

[0019] 2) The greater the viscosity of the sediment, the smaller the flushing rate;

[0020] 3) The greater the dry density of the accumulated sediment, the smaller the flushing rate;

[0021] 4) When the slope of the fluid region (such as river, flow channel, water tank, etc.) is small, the change of the flushing rate with the slope is not obvious; with the increase of the slope, the flushing amount becomes more and more sensitive to the change of the slope;

[0022] 5) When the consolidation time of the sediment is short, t≤10d, the flushing amount is very sensitive to the extension of the consolidation time of the sediment; when the consolidation time of the sediment is long, the flushing amount basically does not change with the extension of the time; according to the record of the reference (TAN Guangming, SHU Caiwen, CHEN Yiming Water Resources and Hydropower. Characteristics of clayey sediment accumulation and consolidation [M]. China Water Resources and Hydropower Press, 2014.), the fitting curve of the change of the flushing amount with the accumulation time is obtained by combining the theoretical calculation value of the accumulation time-flushing amount of TAN Guangming et al. with the measured data, as shown in Figure 1 where J is the slope of the flow channel.

[0023] For an engineering area, the sediment composition and characteristics (sediment particle size, viscosity, dry density) of the region are basically fixed in a long period of time, so the main factor affecting the flushing amount of the accumulated and consolidated sediment in the region is the accumulation and consolidation time of the sediment.

[0024] Based on the above conclusions, in order to reduce the frequency of manual dredging, the problem of silt accumulation in the seawater pump room can be reduced by controlling the duration of silt accumulation and consolidation. Utility Model Content

[0025] In order to achieve the effect of high-speed water flow bottom disturbance without stopping production, it is planned to set small-diameter nozzles in the pump room flow channel, front pool and other areas, and change the nozzle outlet flow rate by controlling the system flow. When the nozzle jet flow rate is greater than or equal to the starting flow rate of the silted sediment and the water flow is sprayed intermittently every day, the silt reduction effect can be achieved. The larger the area of ​​the starting flow rate line, the better the overall silt reduction effect. This method has the following advantages: (1) Under the disturbance of high-speed water flow, some silt can be started, and the suspended sediment can leave the seawater pump room with the water flow, which can reduce the total amount of sediment deposition in the seawater pump room; (2) The intermittent disturbance of high-speed water flow every day can interrupt the consolidation process of the sediment body and alleviate the compaction process of the sediment, which is conducive to the flushing of the silt by water flow and can also reduce the difficulty of future manual dredging.

[0026] The specific scheme of the utility model is as follows:

[0027] A seawater pump room dynamic recoil silt reduction system, the seawater pump room is provided with a water intake channel, one end of the water intake channel is provided with a seawater pump for taking water, the seawater pump is connected to the plant water intake pipeline through the plant water intake pipeline,

[0028] A first backwash pipe is provided on both sides of the water intake channel. The first backwash pipe is connected to the plant water intake pipe. A backwash control valve is connected between the first backwash pipe and the plant water intake pipe. The first backwash pipe is provided with a backwash nozzle. The opening of each backwash nozzle faces the other side, and the backwash nozzles on both sides are staggered in the horizontal direction. The backwash nozzle is 10-20 cm away from the bottom of the water intake channel. The backwash nozzle is a duckbill-shaped nozzle with a flat water outlet.

[0029] Furthermore, a forebay is provided between the water intake channel and the seawater, and the width of the forebay is greater than the width of the water intake channel;

[0030] A plurality of second backwash pipes connected to the plant water intake pipe are provided on both sides of the forebay, and a backwash control valve is connected between the second backwash pipe and the plant water intake pipe;

[0031] A backwash nozzle is provided on the second backwash pipe, and the backwash nozzles distributed on the first backwash pipe and the second backwash pipe have the same specification parameters.

[0032] Furthermore, an automatic control system combining automatic and manual control modes is adopted to achieve daily intermittent recoil control.

[0033] Further, the first backwashing pipeline and the second backwashing pipeline are respectively provided with a flow regulating valve or a booster pump.

[0034] Further, an automatic control system is further included, which is connected with the backwashing control valves.

[0035] Further, the backwashing nozzles are staggered with the adjacent two backwashing nozzles on the opposite side, and the interval of the backwashing nozzles is 1.6-2.5 m.

[0036] Further, the interval of the adjacent two backwashing nozzles is 2 m, and the backwashing nozzles on the two sides are staggered by 1 m in the horizontal direction.

[0037] Further, the backwashing nozzles are provided with a kidney-shaped water outlet, and the horizontal opening width of the kidney-shaped water outlet is 60-70 mm, and the height is 10 mm.

[0038] Further, the backwashing control valve is an electric butterfly valve.

[0039] Further, the backwashing nozzles are fixedly installed on the first backwashing pipeline and the second backwashing pipeline in a welding manner.

[0040] Further, a rotating filter screen is arranged at the other end of the water taking flow channel, and the rotating filter screen comprises a rotating roller and a flushing pipeline, and the flushing pipeline is connected with the water taking pipeline of the factory area.

[0041] Further, a trash rack and a rotating filter screen are arranged between the front pool and the water taking flow channel.

[0042] Further, a fire-fighting water pump is arranged in the water taking flow channel, and the fire-fighting water pump is connected with the fire-fighting water pipe of the factory building.

[0043] The technical scheme provided by the present application has the following advantages:

[0044] 1. The power backwashing and silt reduction are realized without stopping production, and the production interruption time caused by the desilting operation is effectively reduced.

[0045] 2. The accumulated silt is disturbed by the daily intermittent high-speed water flow, the hardening of the accumulated silt is reduced, and the difficulty and cost of future desilting are reduced.

[0046] 3. The small-diameter nozzle and the accurate flow control are adopted to realize the effective disturbance of the accumulated silt and improve the silt reduction efficiency.

[0047] 4. The backwashing nozzles and the control valves are arranged to realize the automatic backwashing of the water taking flow channel and the front pool, reduce the manual operation, and reduce the labor cost.

[0048] 5. By optimizing the nozzle design and layout, the nozzle's water flow coverage and impact force are ensured, further improving the silt reduction effect;

[0049] 6. The system can monitor and control in real time, improving the stability and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0051] Figure 1 is a graph showing the relationship between scour volume and consolidation time;

[0052] Figure 2 This is a layout diagram of a seawater pump room power backwash desilting system according to the utility model in one embodiment;

[0053] Figure 3 for Figure 2 System layout diagram of one of the water intake channels;

[0054] Figure 4 for Figure 2 System layout diagram of the central forebay;

[0055] Figure 5 This is a backwash nozzle distribution diagram in one of the water intake channels;

[0056] Figure 6 It is a top view of the backwash nozzle;

[0057] Figure 7 This is the rear view of the backwash nozzle;

[0058] Figure 8 It is the front view of the backwash nozzle;

[0059] Figure 9 This is a diagram of the sediment deposition after scouring and silting in Example 1;

[0060] Figure 10 This is a diagram of a multi-nozzle model of a mathematical model flow channel in Example 1;

[0061] Figure 11 This is the flow velocity distribution diagram of the mathematical model flow channel multi-nozzle model in Example 1. DETAILED DESCRIPTION

[0062] In the following description, a large number of specific details are given to provide a more thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without one or more of these details. In other instances, well-known features have not been described in detail to avoid obscuring the present application.

[0063] In order to thoroughly understand the present application, detailed steps and detailed structures will be proposed in the following description in order to explain the technical scheme of the present application. The preferred embodiments of the present application are described in detail as follows, however, in addition to these detailed descriptions, the present application can also have other implementation manners.

[0064] Figures 3-7 As shown in an embodiment, the present application is a layout of a seawater pump house power backflush silt reduction system, the seawater pump house is provided with six front pools 200 in total of A8-A12 and seven water intake flow channels 100 in total of A1-A7, the width of the front pool 200 is greater than the width of the water intake flow channel 100.

[0065] The water intake flow channel 100 is connected with seawater through the front pool 200, and the seawater enters the water intake flow channel 100 through the front pool 200. The water intake flow channel 100 and the front pool 200 are provided with a water intake gate 110 in the middle, and the other end of the water intake flow channel 100 is provided with a seawater pump 120 for water intake, the seawater pump 120 is connected with the plant water intake pipeline through the plant water intake pipeline, and seawater is pumped by the seawater pump 120 for use of the plant water intake pipeline.

[0066] The water intake flow channel 100 can also be provided with a fire water pump 170, and the fire water pump 170 is connected with the fire water pipe of the plant. The fire water pump 170 can directly use seawater as the fire water of the plant.

[0067] A rotating filter screen 130 is arranged in the water intake flow channel 100 close to the water intake gate 110, the rotating filter screen 130 comprises a rotating roller and a flushing pipeline, the flushing pipeline is connected with the plant water intake pipeline, the rotating roller is provided with a sewage discharge port higher than the ground, and the sewage discharge port is connected with a sewage collecting device 180 on the ground. The side of the rotating filter screen 130 close to the front pool 200 is also provided with a trash rack 160, which can also play a filtering role to avoid large particles from entering the rotating filter screen 130 to cause damage to the rotating roller.

[0068] The first backwashing pipe 140 is arranged on both sides of the water intake channel 100, and the second backwashing pipe 240 is arranged on both sides of the front pool 200. The first backwashing pipe 140 and the second backwashing pipe 240 are connected with the plant water intake pipeline of the seawater pump 120, and the first backwashing pipe 140 and the second backwashing pipe 240 are connected with the plant water intake pipeline through a backwashing control valve. The first backwashing pipe 140 on both sides of the water intake channel 100 and the second backwashing pipe 240 on both sides of the front pool 200 are welded with backwashing nozzles 150. The openings of the backwashing nozzles 150 on each side face the other side, and the backwashing nozzles 150 on both sides are staggered in the horizontal direction. After the backwashing control valve is opened, the seawater pumped by the seawater pump 120 is sprayed at high speed from the backwashing nozzles 150 as backwashing water for dredging.

[0069] In an optional embodiment, the backwashing nozzle 150 is 10-20 cm away from the bottom of the water intake channel 100. If the height of the backwashing nozzle 150 is too low, it is easy to cause the silt to block the backwashing nozzle 150, and if the height is too high, it is easy to cause the dredging effect to be unsatisfactory. After model verification, it is found that the distance between the backwashing nozzle 150 and the bottom of the water intake channel 100 is 10-20 cm, preferably 15 cm.

[0070] In an optional embodiment, as shown in Figures 6-8 The backwashing nozzle 150 is a duckbill-shaped nozzle with a flat water outlet. The cross-sectional shape of the water outlet is a waist-round shape. By adopting the duckbill-shaped nozzle, a wider spraying range and stronger impact force can be achieved, thereby improving the efficiency of backwashing. The flat water outlet design enables the water flow to cover a larger area during spraying while maintaining a high flow rate, which is very effective for removing silt from the bottom of the water intake channel and the front pool. In addition, the waist-round-shaped water outlet design helps to reduce the degree of turbulence of the water flow, making the backwashing process more stable and uniform. By precisely controlling the size and shape of the nozzle, the backwashing effect can be further optimized to ensure the cleanliness and efficient operation of the water intake system. Preferably, the horizontal opening width of the waist-round-shaped water outlet is 60-70 mm, and the height is 10 mm.

[0071] The first backwashing pipe 140 and the second backwashing pipe 240 are both provided with a flow regulating valve or a booster pump. The flow regulating valve can adjust the flushing flow of the backwashing nozzle 150 to meet different dredging needs. The booster pump is used when the pumping pressure of the seawater pump 120 is insufficient to cause unsatisfactory flushing effect, so as to start the booster pump to increase the backwashing water pressure of the backwashing nozzle 150, so as to ensure the dredging effect.

[0072] As shown in Figure 5As shown, the backwash nozzles 150 on one side of the present invention are staggered with the two adjacent backwash nozzles 150 on the opposite side. In one embodiment, the spacing between the backwash nozzles 150 on the same side is 2m, and the backwash nozzles 150 on both sides are staggered by 1m. This design can ensure that when the backwash nozzles 150 are working, the water flow can cover the entire width of the water intake channel 100, thereby achieving a comprehensive silt removal effect. At the same time, the staggered layout helps to reduce the mutual interference between the water flows, so that each nozzle can exert its maximum cleaning efficiency. In addition, the spacing and staggered distance of the nozzles have been carefully calculated to adapt to water intake systems of different sizes, ensuring that the ideal silt removal effect can be achieved under various working conditions.

[0073] In an optional embodiment, the backwash control valve is an electric butterfly valve connected to an automatic control system via a control circuit, enabling remote operation. The opening and closing of the backwash control valve is automatically controlled by a central control system according to a pre-set program, ensuring the accuracy and efficiency of the backwash process. Furthermore, the electric butterfly valve offers excellent sealing properties, effectively preventing water leakage during backwashing and ensuring stable system operation. During the backwash process, the electric butterfly valve's rapid response reduces head loss and improves backwash efficiency. Through its optimized design, the electric butterfly valve has a long service life and low maintenance costs, further reducing operating costs.

[0074] In an optional embodiment, a liquid level meter is provided in the water intake channel 100 , and the liquid level meter and the backwash control valve are connected to an automatic control system. The backwash control valve can be adjusted to start / stop backwashing according to the liquid level meter data.

[0075] Example One

[0076] In order to verify the operating effect of this power recoil system, the applicant conducted physical model and mathematical model tests respectively:

[0077] 1. Physical Model

[0078] The physical model was used to verify the sediment removal performance of a single recoil nozzle. Test sand was collected from a receiving station project in a certain area of ​​Jiangsu Province, and the sediment sample was collected from the surface layer below 0.5 m. Laboratory analysis showed that the median particle size of the sediment sample was approximately 0.1111 mm. After the sand sample was allowed to settle naturally for 24 hours, the starting flow velocity at a water depth of 0.10 m was approximately 0.20-0.25 m / s; and the starting flow velocity at a water depth of 1.0 m was approximately 0.3 m / s.

[0079] To study the sediment scouring effect of the backwash nozzle, the following physical model was established: the model had a 1:1 scale and a rectangular flume with a width of 1 m and a length of 5 m. The nozzle was installed on the short side wall of the rectangle, at an elevation of 5 cm from the bottom plate. Several measuring points were arranged in the flume, and the flow velocity at each location was measured using a three-dimensional flow meter.

[0080] The test content is: after laying the prototype sediment at the bottom of the water tank for 24 hours, the thickness is about 2cm; after laying, the water tank is filled with water to flush the sediment in the tank, and the flushing ability of the backwash nozzle is studied by changing the nozzle flow rate. At the same time, the relationship between the maximum flushing range and the nozzle outlet flow rate can be obtained. The flushing time in the experiment is 10 minutes, and the flushing flow rate q is 12.6m 3 / h、17.6m 3 / h、23.0m 3 / h and 30.2m 3 / h.

[0081] With system flow q = 17.6m 3 / h (nozzle outlet velocity v = 7m / s) as an example, the test results are shown in Figure 9 After actual scouring and sedimentation, there are obvious signs of sediment movement at the bottom of the flume. There is a dividing line between the moved and deposited sediments. The maximum distance from the dividing line to the nozzle outlet is the maximum scouring distance under this flow rate.

[0082] It has been observed that the larger the scouring and silting flow rate, the greater the scouring angle on both sides of the nozzle and the greater the maximum scouring distance. A fitting formula is proposed based on the scouring and silting distance under different flow rates, which can be used to select the flow rate according to different distance requirements.

[0083] 2. Mathematical Model

[0084] To investigate the silting effect of the backflush system within the actual pump room flow environment, a 1:1 mathematical model of the pump room flow path was established. The model calculations employed Ansys Fluent for meshing and finite element analysis. The mathematical model of a single nozzle was compared with the physical model, and appropriate calculation parameters were calibrated to ensure accuracy.

[0085] Model building includes the following:

[0086] 1) Dimensional parameters: The flow channel dimensions are 23.15m long and 3m wide. The nozzles are arranged in the flow channel at a height of 10cm from the flow channel bottom plate.

[0087] 2) Boundary conditions: The nozzle outlet is a velocity outlet, and the flow rate is used as the control variable;

[0088] 3) Selection of nozzle outlet velocity: According to the estimation of the formula of Zhang Ruijin, Sha Yuqing and others, under the water depth conditions set in the model, the sediment starting velocity is about 0.54m / s. Therefore, the nozzle outlet velocity is selected in the range of 7-17m / s to achieve the effect of flushing a wide range of sediment as much as possible without affecting the jet of adjacent nozzles. The final nozzle outlet velocity is set to 9m / s for model calculation; the multi-nozzle model of the flow channel established by Ansys is as followsFigure 10 The results of the mathematical model are shown in the following table.

[0089] The results of the mathematical model are shown in the following table. Figure 11 As shown in the table, the jet flow of the nozzle only affects the water body within a height range of about 15 cm at the bottom of the flow passage, and the area of the region where the flow rate reaches above 0.54 m / s can reach above about 60% in the region where the nozzle is arranged. Through simulation calculation of different nozzle arrangements, it is obtained that, in the case of equidistant staggered arrangement of the nozzles, the side-by-side nozzle spacing is within an acceptable range of 1.6-2.5 m, and when the spacing is 1.6 m, the nozzle spacing is smaller, and the opposite side nozzles are more likely to affect each other; when the spacing is 2.5 m, the nozzle spacing is larger, and the area of the region in the nozzle arrangement area that does not meet the sediment starting flow rate requirement is larger, and the sediment reduction effect is not ideal; therefore, the nozzle spacing of about 2 m is the best choice, and the dredging effect is the most ideal.

[0090] (3) Conclusion

[0091] Through the simulation verification of the above physical model and mathematical model, the use of the power backflushing system will bring the following advantages:

[0092] 1. The application in the flow passage of the pump house can achieve good sediment reduction effect, and can start about 60% of the sediment in the installation range.

[0093] 2. The system can automatically operate under the set conditions, the sediment started by the jet flow of the nozzle can flow along the flow passage, be pumped away from the seawater pump house, reduce the accumulation in the pump house without stopping production, reduce the frequency of manual dredging, and improve the production efficiency of the plant area.

[0094] 3. The system disturbs the accumulated sediment at the bottom of the pump house through the high-speed jet flow of the nozzle, on the one hand, most of the sediment can be started and removed from the pump house by the seawater pump, and on the other hand, the accumulated sediment is disturbed intermittently every day, which breaks the whole accumulation and consolidation period and delays the consolidation process of the cohesive sediment, thereby reducing the difficulty of manual dredging.

[0095] It should be noted that when the power backflushing device is started, the branch nozzle outlet flow uniformly reaches the requirement within 30 seconds to avoid sudden start to cause large disturbance to the water body, and when the system is turned off, the nozzle outlet flow uniformly decreases to zero within 30 seconds, and the start / turn-off time can be adjusted. Each region is washed in turn, and the control program can preset the always-off region.

[0096] The power backflushing device has two operation modes: local mode and remote mode.

[0097] Local control is set up and operated via a local control cabinet installed in the pump room. This cabinet houses a PLC and touch screen, and transmits power recoil system process parameter information to the DCS via Modbus RTU protocol, allowing remote operation from the DCS. Remote local switching is achieved via a soft-switch button installed on the local control panel.

[0098] The power recoil device has two working modes: manual mode and automatic mode.

[0099] The manual mode is mainly used for testing pipeline electric butterfly valves. In manual mode, any electric butterfly valve can be operated through the touch screen, and its status feedback can be used to test whether the butterfly valve is working properly. The manual operation process is as follows:

[0100] 1) Select manual mode on the touch screen or DCS operation screen;

[0101] 2) Open the electric butterfly valve of the branch to the area that needs to be flushed

[0102] 3) Open the electric butterfly valve in the flushing area. The system automatically determines the required flow rate according to the area to be flushed, opens the electric butterfly valve of a regulating valve branch, and slowly adjusts the flow rate through the regulating valve (determined by digital and physical models). If the required flow rate can be automatically adjusted, the system operates normally. Otherwise, the system automatically closes the electric butterfly valve and regulating valve of the branch, opens the electric butterfly valve of the water pump branch, starts the pump, and adjusts the required flow rate through the regulating valve and the variable frequency pump to perform the power backwash operation;

[0103] 4) Close the regulating valve (or booster pump) and electric butterfly valve of the backwash pipe branch used to stop backwashing in the flushing area.

[0104] The automatic mode is used for power recoil operation under normal operating conditions. The operating parameters of the power recoil equipment in automatic mode can be set according to actual conditions. The specific operating steps are as follows:

[0105] 1) Select automatic mode on the touch screen or DCS operation screen;

[0106] 2) Automatic flushing parameter settings: daily flushing time (default 6:00 AM and 18:00 PM) or water level value (determined by the specific project scenario), number of flushes per day (default setting value is 2), number of flushing minutes per area (default setting value is 5 minutes), time for nozzle outlet flow to reach the design value (default setting value is 30 seconds), time for nozzle outlet flow to drop to zero (default setting value is 30 seconds).

[0107] 3) Click the "Power Recoil" button.

[0108] During the power recoil process, the program execution workflow is as follows:

[0109] 1) Close all electric butterfly valves;

[0110] 2) Open the electric butterfly valve in the area to be flushed as recorded;

[0111] 3) After receiving the open feedback signal of the electric butterfly valve in the required flushing area, the system automatically determines the required flow rate (determined by digital and physical models) according to the area to be flushed, opens the electric butterfly valve of a backwash pipe branch, and slowly adjusts the flow rate through the regulating valve. If the required flow rate can be automatically adjusted, the system operates normally. Otherwise, the system automatically closes the electric butterfly valve and regulating valve of the branch, opens the electric butterfly valve of the water pump branch, starts the pump, and adjusts the flow rate to the required flow rate through the regulating valve and the variable frequency pump to perform the power backwash operation;

[0112] 4) After the timing is completed, record and close the electric butterfly valve of the area, open the electric butterfly valve of the next flushing area, and repeat 3) to 4) until the last flushing area;

[0113] 5) Close the regulating valve (or booster pump) and electric butterfly valve of the branch used, and close the electric butterfly valve in the flushing area;

[0114] 6) Exit the automatic recoil program.

[0115] If an error occurs during the power recoil process, such as a valve timeout, the program will execute as follows:

[0116] 1) If it is determined that the main line is wrong, it will cause the program to automatically exit. In this case, the program will close all valves, switch the operation mode to manual, and record the execution error record of the power recoil for maintenance personnel to review and track.

[0117] 2) If it is determined that the branch line is wrong, further determine whether the valve of the pipeline can be closed. If it cannot be closed, handle it according to the situation 1);

[0118] 3) If a branch line error is detected, the system further determines whether the valve in that line can be closed. If the line can be closed, the system records the error and automatically switches to the next line to execute the backflush command.

[0119] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-mentioned disclosed methods and technical contents to make many possible changes and modifications to the technical solutions of the present invention without departing from the scope of the technical solution of the present invention, or modify them into equivalent embodiments with equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention that do not depart from the content of the technical solution of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. A seawater pump room power backwash desilting system, wherein the seawater pump room is provided with a water intake channel (100), one end of the water intake channel (100) is provided with a seawater pump (120) for taking water, and the seawater pump (120) is connected to the plant water system through a plant water intake pipeline, characterized in that: A first backwash pipe (140) is provided on both sides of the water intake channel (100), the first backwash pipe (140) is connected to the plant water intake pipeline, a backwash control valve is connected between the first backwash pipe (140) and the plant water intake pipeline, the first backwash pipe (140) is provided with a backwash nozzle (150), the opening of the backwash nozzle (150) on each side is facing the other side, and the backwash nozzles (150) on both sides are staggered in the horizontal direction, the backwash nozzle (150) is 10-20 cm away from the bottom of the water intake channel (100), and the backwash nozzle (150) is a duckbill-shaped nozzle with a flat water outlet.

2. A seawater pump room dynamic recoil desilting system according to claim 1, characterized in that: A forebay (200) is further provided between the water intake channel (100) and the seawater, and the width of the forebay (200) is greater than the width of the water intake channel (100); A plurality of second backwash pipes (240) connected to the plant water intake pipeline are provided on both sides of the forebay (200), and the backwash control valve is connected between the second backwash pipe (240) and the plant water intake pipeline; The backwash nozzle (150) is provided on the second backwash pipe (240), and the backwash nozzles (150) distributed on the first backwash pipe (140) and the second backwash pipe (240) have the same specification parameters.

3. A seawater pump room dynamic recoil desilting system as claimed in claim 2, characterized in that: The first backwash pipeline (140) and the second backwash pipeline (240) are both provided with a flow regulating valve or a booster pump.

4. The seawater pump room dynamic recoil desilting system according to claim 1, characterized in that: It also includes an automatic control system, which is connected to each of the backwash control valves.

5. The seawater pump room dynamic recoil desilting system according to claim 2, characterized in that: Any one of the backwash nozzles (150) is arranged alternately with two adjacent backwash nozzles (150) on the opposite side, and the spacing between the backwash nozzles (150) is 1.6-2.5 m.

6. The seawater pump room dynamic recoil desilting system according to claim 2, characterized in that: The distance between two adjacent backwash nozzles (150) is 2m, and the backwash nozzles (150) on both sides are staggered by 1m in the horizontal direction.

7. The seawater pump room dynamic recoil desilting system according to claim 2, characterized in that: The backwash nozzle (150) is provided with a waist-shaped water outlet, and the horizontal opening width of the waist-shaped water outlet is 60-70 mm and the height is 10 mm.

8. The seawater pump room dynamic recoil desilting system according to claim 1, characterized in that: The backwash control valve is an electric butterfly valve.

9. The seawater pump room dynamic recoil desilting system according to claim 2, characterized in that: The backwash nozzle (150) is fixedly mounted on the first backwash pipe (140) and the second backwash pipe (240) by welding.

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