Large seawater desalination and filtration treatment system

Abstract

The utility model discloses a large-scale seawater desalination and filtration treatment system which comprises a booster pump, a filtration water inlet valve, a polymer microporous filter material filter, a filtration water outlet valve and a clear water tank which are connected in sequence, and a water outlet of the clear water tank is connected with seawater reverse osmosis equipment; a stirrer is arranged in the polymer microporous filter material filter; a backwashing water inlet valve is arranged in the backwashing water inlet pipeline; a lower blow-off valve is arranged in the backwashing blow-off pipeline; the device further comprises a forward flushing blow-off pipeline, and an upper blow-off valve is arranged in the forward flushing blow-off pipeline. According to the scheme, the operation cost is lower, the occupied area is smaller, the treatment effect is better, the processes of back flushing, forward flushing and the like are facilitated, and it is guaranteed that the system is in a good operation state.

Description

Technical Field

[0001] This utility model belongs to the field of seawater desalination technology, specifically relating to a large-scale seawater desalination filtration system. Background Technology

[0002] Currently, large-scale membrane-based seawater desalination filtration processes mainly include mechanical filtration, adsorption filtration, and membrane filtration. Mechanical filtration has many types, with ultra-large horizontal pressure filters or V-type filter beds being the most common. However, these have slow filtration rates and require a large footprint; the effluent turbidity cannot meet the requirements for seawater reverse osmosis feed water. Adsorption filtration typically uses activated carbon as the adsorbent, mainly for removing organic matter or residual chlorine, but retains relatively little suspended solids; it requires high feed water quality and is easily broken. Membrane filtration has high investment and operating costs, high self-consumption rate, and requires consideration of water temperature. Conventional filtration and ultrafiltration equipment have strict requirements for the suspended solids content of the feed water. Generally, fine sand filters require ≤5mg / L of suspended solids in the feed water, quartz sand and dual-media filters require ≤20mg / L, activated carbon filters require ≤3NTU of turbidity in the feed water, and internal pressure ultrafiltration membranes require <5NTU of turbidity in the feed water. An additional stage of filtration is required before these stages, and the influence of water temperature must be considered. For water with low turbidity but algae contamination, conventional filtration and ultrafiltration equipment cannot be used directly. An air flotation tank must be installed before the water enters such equipment to remove algae. Therefore, the existing treatment processes described above suffer from high investment and operating costs, high self-consumption rate, slow filtration rate, large footprint, strict requirements on influent suspended solids content, and inability to operate normally after algae clogging. Furthermore, the filtration system must also consider daily maintenance and cleaning to ensure it operates in good condition. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a large-scale seawater desalination filtration system that solves the problems of high cost, high self-use rate and slow filtration speed of existing processes, and achieves lower operating cost, smaller footprint, better treatment effect, and facilitates backwashing, forward rinsing and other processes.

[0004] According to the technical solution of this utility model, this utility model provides a large-scale seawater desalination and filtration system, including a booster pump, a filter inlet valve, a polymer microporous filter media, a filter outlet valve, and a clear water tank, which are connected sequentially through pipelines from the input to the output direction of coastal water. The clear water tank has an outlet, which is connected to a seawater reverse osmosis device. A stirrer is installed in the polymer microporous filter media. The system also includes a backwash inlet pipeline, which contains a backwash inlet valve. One end of the backwash inlet pipeline is connected to the pipeline between the booster pump and the filter inlet valve. The system includes a backwash inlet pipe, the other end of which is connected to the pipe between the polymer microporous filter and the filter outlet valve; it also includes a backwash drain pipe, which is equipped with a lower drain valve, one end of which is connected to the input end of the polymer microporous filter, and the other end of which is the drain outlet; and a forward flush drain pipe, which is equipped with an upper drain valve, one end of which is connected to the output end of the polymer microporous filter, and the other end of which is connected to the drain outlet.

[0005] In some embodiments, a differential pressure transmitter and a turbidity meter are also included, both of which are located upstream of the filtered water outlet valve.

[0006] In some embodiments, the polymer microporous filter is vertically arranged, with the input end of the polymer microporous filter located at the bottom and the output end of the polymer microporous filter located at the top.

[0007] In some implementations, the filter inlet valve, filter outlet valve, backwash inlet valve, lower drain valve, and upper drain valve are all electric or pneumatic valves that can be automatically controlled by a control system.

[0008] In some implementations, the upstream side of the sewage outlet has a shared sewage pipeline that is shared by the backwash sewage pipeline and the forward flush sewage pipeline, and the output sides of the lower sewage valve and the upper sewage valve are both connected to the input end of the shared sewage pipeline.

[0009] In some embodiments, the system also includes a venting pipeline with a venting valve, one end of which is connected to the input side of the lower drain valve, and the other end of which is connected to the drain pipeline.

[0010] Compared with the prior art, the beneficial technical effects of this utility model are as follows:

[0011] This invention relates to a large-scale seawater desalination filtration system that innovatively utilizes a polymer microporous filter as a large-scale membrane seawater desalination filtration process. This filter effectively removes suspended solids and algae, fully leveraging this property. It can replace processes such as "air flotation tank + V-type filter or pressure filter" for treating seawater with low suspended solids and algae. Furthermore, it features high filtration speed, small footprint, high turbidity removal rate, and effluent turbidity that meets the requirements for reverse osmosis feed water. Investment and operating costs are low, and self-consumption rate is low (≤1%). The system also achieves smooth and efficient operation of normal filtration, shutdown agitation, backwashing, forward flushing, and sewage discharge through agitators, pipelines, and valves. Preferably, it operates automatically based on effluent turbidity and inlet / outlet pressure difference, eliminating the need for manual operation, thus improving automation, reducing labor costs and intensity, and ensuring optimal system operation, thereby increasing treatment efficiency and equipment lifespan. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the system structure provided by this utility model.

[0013] Explanation of reference numerals in the attached figures:

[0014] 1. Booster pump; 2. Polymer microporous filter media; 3. Clean water tank; 4. Filter inlet valve; 5. Filter outlet valve; 6. Agitator; 7. Backwash inlet pipeline; 8. Backwash inlet valve; 9. Backwash drain pipeline; 10. Lower drain valve; 11. Forward flush drain pipeline; 12. Upper drain valve; 13. Differential pressure transmitter; 14. Turbidity meter; 15. Common drain pipeline; 16. Equipment vent pipeline; 17. Equipment vent valve. Detailed Implementation

[0015] This invention provides a large-scale seawater desalination filtration system that solves the problems of high cost, high self-use rate, and slow filtration speed in existing processes. It achieves lower operating costs, smaller footprint, and better treatment effect, and facilitates backwashing and forward rinsing processes. A typical embodiment of this invention mainly includes a booster pump, a polymer microporous filter media, a clear water tank, supporting pipelines, valves, instruments, and a control system. Seawater (or coagulated and clarified seawater) is boosted by the booster pump to the polymer microporous filter media, which simultaneously filters and adsorbs, effectively removing suspended solids and algae from the seawater. The effluent turbidity meets the influent requirements for seawater reverse osmosis. The product water is collected in the clear water tank and used in subsequent seawater reverse osmosis treatment processes.

[0016] Please see Figure 1This utility model discloses a large-scale seawater desalination and filtration system, comprising a booster pump 1, a filter inlet valve 4, a polymer microporous filter media 2, a filter outlet valve 5, and a clear water tank 3, all connected sequentially via pipelines from seawater input to output. The input end of the booster pump 1 is connected to the inlet pipeline of the filtration system, thereby inputting the seawater to be treated. The clear water tank 3 has an outlet, which is connected to a seawater reverse osmosis device for subsequent seawater reverse osmosis treatment; furthermore, an outlet booster pump is located between the outlet of the clear water tank 3 and the seawater reverse osmosis device.

[0017] The polymer microporous filter, also known as a microfiltration filter, is a device that uses polymer microporous suspended filter media particles as the filter medium to intercept and filter suspended solids, algae, colloids, etc. in water at ultra-high flow rates (e.g., 45 m / h to 80 m / h). Preferably, the polymer microporous filter 2 is vertically arranged, with the inlet end located at the bottom and the outlet end at the top, so that the seawater flows counter-currently from bottom to top during the filtration process, which is beneficial to improving the uniformity of water distribution. The polymer microporous filter 2 is equipped with a stirrer 6, which is connected to a motor to drive and agitate the water and filter medium inside the polymer microporous filter 2 during maintenance and cleaning, thereby restoring the filter medium's filtration and adsorption capacity.

[0018] Furthermore, it also includes a backwash inlet pipe 7, which is equipped with a backwash inlet valve 8. One end of the backwash inlet pipe 7 is connected to the pipeline between the booster pump 1 and the filter inlet valve 4, and the other end of the backwash inlet pipe 7 is connected to the pipeline between the polymer microporous filter 2 and the filter outlet valve 5. It also includes a backwash drain pipe 9, which is equipped with a lower drain valve 10. One end of the backwash drain pipe 9 is connected to the input end of the polymer microporous filter 2, and the other end of the backwash drain pipe 9 is the drain outlet. It also includes a forward flush drain pipe 11, which is equipped with an upper drain valve 12. One end of the forward flush drain pipe 11 is connected to the output end of the polymer microporous filter 2, and the other end of the forward flush drain pipe 11 is connected to the drain outlet.

[0019] The system of this utility model can achieve the following process. The normal filtration process is as follows: open the filter inlet valve 4 and the filter outlet valve 5, and the seawater to be treated flows along... Figure 1The main pipeline, shown by the thick solid line, passes sequentially through booster pump 1, polymer microporous filter media 2, and finally enters the clean water tank 3. During maintenance and cleaning, the filter first undergoes a shutdown and agitation process. The filter inlet valve 4 and filter outlet valve 5 are closed, and the agitator 6 is turned on to fully agitate the water and filter media within the polymer microporous filter media 2. Next, a backwashing agitation process is performed. The backwash inlet valve 8 and the lower drain valve 10 are opened, allowing the seawater to be treated, or other backwashing water, to be used as flushing water. This water flows through booster pump 1 and backwash inlet pipeline 7 into the normal output end of the polymer microporous filter media 2, flows backward through the filter media 2, and is then discharged from its normal input end. After backwashing and agitation are completed, forward rinsing is performed. The agitator 6, backwash inlet valve 8, and lower drain valve 10 are closed. The filter inlet valve 4 and upper drain valve 12 are opened. The seawater to be treated is used as rinsing water, or other rinsing water is used separately. It flows forward through the polymer microporous filter media 2 in the normal filtration input / output direction via the booster pump 1, and then discharged through the forward rinsing drain pipe 11. After forward rinsing is completed, the upper drain valve 12 is closed, and the next round of normal filtration begins.

[0020] Furthermore, it also includes a differential pressure transmitter (PDT) 13 and a turbidity meter 14, both of which are located upstream of the filter outlet valve 5. More specifically, the differential pressure transmitter 13 is connected to both the downstream side of the booster pump 1 and the upstream side of the filter outlet valve 5, and is used to monitor the pressure difference between the inlet and outlet water. The turbidity meter 14 is used to monitor the turbidity of the outlet water. Thus, when the outlet turbidity NTU is unqualified or the pressure difference between the inlet and outlet water exceeds the limit, the aforementioned series of maintenance and cleaning processes are performed.

[0021] Preferably, the filter inlet valve 4, filter outlet valve 5, backwash inlet valve 8, lower drain valve 10, and upper drain valve 12 are all automatic valves that can be automatically controlled by the control system, specifically electric or pneumatic valves, so that the aforementioned series of filtration and maintenance cleaning processes can be performed automatically. More preferably, the control system can automatically operate the maintenance cleaning process based on the monitoring results of the differential pressure transmitter 13 and the turbidity meter 14, without manual operation.

[0022] Preferably, the upstream side of the sewage outlet has a shared sewage pipe 15, which is shared by the backwash sewage pipe 9 and the forward flush sewage pipe 11. The output sides of the lower sewage valve 10 and the upper sewage valve 12 are both connected to the input end of the shared sewage pipe 15, so as to simplify the structure. More preferably, it also includes an equipment vent pipe 16, in which an equipment vent valve 17 is provided. One end of the equipment vent pipe 16 is connected to the input side of the lower sewage valve 10, and the other end of the equipment vent pipe 16 is connected to the sewage pipe 15. The equipment vent valve 17 is a normally closed manual valve that is opened under specific conditions to realize bottom sewage discharge of the entire system and empty the water in the system.

[0023] In summary, this utility model's large-scale seawater desalination filtration system innovatively utilizes a polymer microporous filter as a large-scale membrane seawater desalination filtration process. This filter can remove suspended solids and algae, fully leveraging this property. It can replace processes such as "air flotation tank + V-type filter or pressure filter" for treating seawater with low suspended solids and algae. The algae removal rate can reach 90%. Air flotation tanks require the addition of coagulants and flocculants during operation, while the polymer microporous filter eliminates the need for chemical addition, making it more environmentally friendly and economical. Furthermore, the filtration rate of the polymer microporous filter media is 45m / h to 80m / h, which is much higher than that of conventional filters (fine sand filtration 6m / h to 8m / h; single-layer filter media filtration 8m / h to 10m / h; double-layer filter media filtration 10m / h to 14m / h; variable porosity filtration 18m / h to 21m / h; fiber filtration 20m / h to 40m / h). Therefore, a single unit (with a diameter of, for example, DN5000mm) can achieve an output of up to 1500m³ / h. 3 This system, with a capacity of [ / h], is suitable for large-scale systems. Furthermore, it has a small footprint, high turbidity removal rate, and effluent turbidity meets the requirements for seawater reverse osmosis feed water. It also boasts low investment and operating costs and a low self-consumption rate (≤1%). Under normal operating conditions, the turbidity reduction rate of the polymer microporous filter media can reach over 98%. When the filter influent turbidity is ≤10 NTU, the effluent turbidity is ≤0.2 NTU; when the filter influent turbidity is ≤30 NTU, the effluent turbidity is ≤0.6 NTU. Moreover, through agitators, pipelines, and automatic valves, it ensures smooth and efficient operation of processes such as normal filtration, shutdown agitation, backwashing, forward flushing, and sewage discharge. The preferred method is automatic operation based on effluent turbidity and influent / outfluent pressure difference, eliminating the need for manual operation, thus improving automation, reducing labor costs and intensity, and making it easier to ensure good system operation, contributing to improved treatment efficiency and equipment lifespan. Routine maintenance and cleaning of the filter media involves stirring and rinsing with raw water, without the need for an air source or chemical agents. Only when the effluent turbidity requirement is high, the impact on the filter media's dirt-holding capacity is significant, or the incoming water is particularly dirty, is it necessary to use acids, alkalis, bactericides, etc., for deep cleaning and regeneration of the filter media.

Claims

1. A large-scale seawater desalination and filtration system, characterized in that, The system includes a booster pump (1) connected sequentially through pipelines from the input to the output of coastal water, a filter inlet valve (4), a polymer microporous filter media (2), a filter outlet valve (5), and a clear water tank (3). The clear water tank (3) has an outlet, which is connected to the seawater reverse osmosis equipment. The polymer microporous filter media (2) is equipped with a stirrer (6). It also includes a backwash water inlet pipe (7), in which a backwash water inlet valve (8) is provided. One end of the backwash water inlet pipe (7) is connected to the pipeline between the booster pump (1) and the filter water inlet valve (4), and the other end of the backwash water inlet pipe (7) is connected to the pipeline between the polymer microporous filter (2) and the filter water outlet valve (5). It also includes a backwash drain pipe (9), which is equipped with a lower drain valve (10). One end of the backwash drain pipe (9) is connected to the input end of the polymer microporous filter (2), and the other end of the backwash drain pipe (9) is the drain outlet. It also includes a forward flushing and sewage discharge pipeline (11), in which an upper sewage discharge valve (12) is provided. One end of the forward flushing and sewage discharge pipeline (11) is connected to the output end of the polymer microporous filter (2), and the other end of the forward flushing and sewage discharge pipeline (11) is connected to the sewage outlet.

2. The large-scale seawater desalination and filtration system according to claim 1, characterized in that, It also includes a differential pressure transmitter (13) and a turbidity meter (14), both of which are located upstream of the filter outlet valve (5).

3. The large-scale seawater desalination and filtration system according to claim 1, characterized in that, The polymer microporous filter (2) is vertically arranged, with the input end of the polymer microporous filter (2) located at the bottom and the output end of the polymer microporous filter (2) located at the top.

4. The large-scale seawater desalination and filtration system according to claim 1, characterized in that, The filter inlet valve (4), filter outlet valve (5), backwash inlet valve (8), lower drain valve (10), and upper drain valve (12) are all electric or pneumatic valves that can be automatically controlled by the control system.

5. The large-scale seawater desalination and filtration system according to claim 1, characterized in that, The upstream side of the sewage outlet has a shared sewage pipeline (15) that is shared by a backwash sewage pipeline (9) and a forward flush sewage pipeline (11). The output sides of the lower sewage valve (10) and the upper sewage valve (12) are both connected to the input end of the shared sewage pipeline (15).

6. The large-scale seawater desalination and filtration system according to claim 5, characterized in that, It also includes an equipment venting pipeline (16), in which an equipment venting valve (17) is installed. One end of the equipment venting pipeline (16) is connected to the input side of the lower sewage valve (10), and the other end of the equipment venting pipeline (16) is connected to the sewage pipeline (15).

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