Urban multi-water-source water purification system and water purification treatment method

Abstract

The invention relates to the technical field of water purification processes, in particular to an urban multi-water-source water purification system and a water purification treatment method.The water purification system comprises a switching pipeline, a first treatment unit, a second treatment unit and a water outlet pipeline arranged at the other end of the first treatment unit and the other end of the second treatment unit, the control assembly is used for controlling the flow direction of the raw water; the first treatment unit comprises a flocculation sedimentation tank, a sand filter tank and an ozone activated carbon tank which are communicated in sequence; the second treatment unit comprises a pre-ozone treatment tank, a flocculation sedimentation tank, a sand filter tank, an ozone activated carbon tank, an ultrafiltration membrane tank and a nanofiltration membrane tank which are communicated in sequence. Through arrangement of the control assembly and cooperation of the switching pipeline, the flow direction of the raw water can be adjusted according to the pH value of the raw water, compared with an existing water purification process in which single raw water is matched with a corresponding water purification process, the water purification device is more flexible, the raw water can be subjected to different water purification treatments according to changes of the raw water, and the water purification efficiency is improved. Therefore, the water purification effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of water purification processes, and particularly to an urban multi-source water purification system and a water purification treatment method. Background Art

[0002] With the development of urbanization, the population and industrial scale of many cities have expanded accordingly, and the urban water consumption has also increased. Generally, in order to cope with this situation, urban water supply plants will use multiple water sources for water supply, such as rivers, lakes, urban wetlands, reservoir water sources, etc.

[0003] The water volume of natural water sources such as rivers and lakes is affected by seasonal and climatic conditions, and there are changes in dry seasons and wet seasons. A single water source may not be able to meet the urban water supply demand during the dry season. Therefore, it is necessary to use multiple different water sources, such as reservoirs, rivers, wetlands, lakes, etc., to provide stable water sources for the city.

[0004] However, different water sources require different treatment processes. Even for the same water source, different treatment processes are needed in different seasons. Specifically, when there are too many impurities in the raw water, the raw water only needs to remove the impurities; while in some raw water, seasonal algae blooms may occur, causing a significant increase in the pH value of the water body, and the pH value needs to be adjusted; currently, the treatment device cannot be adjusted in a timely manner according to the raw water situation, which affects the purification effect of the raw water.

[0005] Therefore, it is necessary to provide a water purification system and a treatment method that can purify different water qualities. Summary of the Invention

[0006] The present invention provides an urban multi-source water purification system and a water purification treatment method. Through the allocation of different water treatment processes and the control of precise dosing of different CO 2 not only can the energy consumption of water treatment be reduced, but also the coagulation and sedimentation effect can be effectively improved, and the concentration of aluminum ions in the water body is reduced, thereby promoting the efficient operation of the entire water purification system.

[0007] The specific technical solutions are as follows:

[0008] In a first aspect, the present invention provides an urban multi-source water purification system, including: a switching pipeline, a first treatment unit and a second treatment unit connected to the switching pipeline, a water outlet pipeline provided at the other ends of the first treatment unit and the second treatment unit, and an automatic control system; the first treatment unit includes a coagulation sedimentation tank, a sand filter tank, and an ozone activated carbon tank connected in sequence; the second treatment unit includes a pre-ozonation treatment tank, a coagulation sedimentation tank, a sand filter tank, an ozone activated carbon tank, an ultrafiltration membrane tank, and a nanofiltration membrane tank connected in sequence;

[0009] The described automated control system includes a water quality sensor, a CO 2 injector, a coagulant injector, and a controller; the water quality sensor is provided with water quality monitoring probes respectively installed at the inlet of the coagulation sedimentation tank, the outlet of the coagulation sedimentation tank, the outlet of the ozonated activated carbon tank, the outlet of the ultrafiltration membrane tank, and the outlet of the nanofiltration membrane tank; CO 2 injector is provided with CO aeration ports respectively communicating with the coagulation sedimentation tank, the ozonated activated carbon tank, the ultrafiltration membrane tank, and the nanofiltration membrane tank; 2 The coagulant injector is provided with a coagulant dosing port communicating with the coagulation sedimentation tank;

[0010] The controller includes an information acquisition module, a data processing and analysis module, and a feedback control module; the information acquisition module is used to receive the water quality data information of the water quality monitoring probes and feed back the water quality data information to the data processing and analysis module; the data processing and analysis module receives the data information of the information acquisition module, judges the water source type, and calculates and corrects the CO 2 aeration volume and the coagulant addition amount; the feedback control module includes a water source switching control sub-module, a CO 2 injecting control sub-module and a coagulant dosing control sub-module; the water source switching control sub-module controls the opening and closing of the switching pipeline; CO 2 injecting control sub-module receives the data information of the data processing and analysis module and controls the opening and closing of the CO 2 aeration port and the gas flow rate; the coagulant dosing control sub-module controls the opening and closing of the coagulant dosing port and the dosing flow rate of the coagulant.

[0011] Further, the switching pipeline includes a plurality of raw water pipes, two-position three-way valves arranged on the raw water pipes, a first unit pipe and a second unit pipe communicating with the two-position three-way valves, a first water inlet pipe communicating with the first treatment unit, a second water inlet pipe communicating with the second treatment unit, the second water inlet pipe is connected to the second unit pipe, and the first water inlet pipe is connected to the first unit pipe; the two-position three-way valve is connected to the water source switching control sub-module; water quality monitoring probes are provided on all the raw water pipes.

[0012] Further, the pre-ozonation treatment tank includes a pre-ozonation tank body, first baffle plates arranged at equal intervals in the pre-ozonation tank body, second baffle plates arranged in the pre-ozonation tank body and staggered with the first baffle plates, a plurality of ventilation holes provided on the first baffle plates, ozone inlet pipes installed on the ventilation holes, ozone aeration heads installed on both end faces of the first baffle plates and communicating with the ventilation holes, a first water passage is formed between the bottom surface of the first baffle plate and the bottom surface of the inner cavity of the pre-ozonation tank body, and a second water passage is formed between the top surface of the second baffle plate and the top surface of the pre-ozonation tank body.

[0013] Further, the ultrafiltration membrane tank includes an ultrafiltration tank body, an ultrafiltration membrane module installed in the ultrafiltration tank body, an air diffuser pipe installed on the ultrafiltration tank body, and the bottom of the ultrafiltration membrane module is connected to a water outlet pipeline;

[0014] The nanofiltration membrane tank includes a nanofiltration tank body, a nanofiltration membrane module installed in the nanofiltration tank body, an air diffuser pipe installed on the nanofiltration tank body, and the bottom of the nanofiltration membrane module is connected to a water outlet pipeline;

[0015] The air diffuser pipe is connected to an air pump, and the air inlet end of the air pump is connected to an oxygen storage tank and a CO 2 storage tank;

[0016] The ends of the air distribution branches located in the ultrafiltration tank body and the nanofiltration membrane tank body are both arranged in a ring around the membrane module.

[0017] In a second aspect, the present invention provides a method for treating raw water using the above-mentioned urban multi-source water purification system, including:

[0018] (1) Monitoring the water quality of the raw water pipe, determining whether the raw water type is type A or type B, and controlling the type A raw water to enter the first treatment unit and the type B raw water to enter the second treatment unit by the water source switching control sub-module; The first treatment unit uses method A for water quality treatment, and the second treatment unit uses method B for water quality treatment;

[0019] The water quality judgment conditions for type A raw water are: pH lower than 7.6, turbidity lower than 12 NTU; Raw water with other water quality conditions is determined as type B raw water.

[0020] Method A:

[0021] A-S1: Taking type A raw water as a water sample, obtaining a first theoretical relationship curve between the pH value and the CO 2 aeration volume, and a second theoretical relationship curve between the turbidity and the coagulant addition amount;

[0022] A-S2: Real-time monitoring of the pH value and turbidity at the inlet of the coagulation sedimentation tank, the pH value at the inlet of the ozonated activated carbon filter, and the turbidity at the outlet of the coagulation sedimentation tank;

[0023] A-S3: Retrieving the pH value data of A-S2, and according to the first theoretical relationship curve, obtaining the CO 2 real-time aeration volume in the coagulation sedimentation tank, the ozonated activated carbon filter, and the ultrafiltration membrane filtration tank; Retrieving the turbidity data of A-S2, and according to the second theoretical relationship curve, obtaining the real-time coagulant addition amount in the coagulation sedimentation tank;

[0024] A-S4: According to the CO 2 real-time aeration volume and real-time coagulant addition amount obtained in A-S3, controlling the CO2 emissions, as well as the CO emissions in the coagulation sedimentation tank 2 emissions and the dosage of the coagulant;

[0025] Method B:

[0026] B-S1: Obtain the following data information:

[0027] 1) Using the type B raw water as the water sample, obtain the first deviation relationship curve between the pH value and the CO 2 aeration volume;

[0028] 2) CO 2 average deviation coefficient;

[0029] 3) Using the type B raw water as the water sample, obtain the second deviation relationship curve between the turbidity and the dosage of the coagulant;

[0030] 4) Coagulant average deviation coefficient;

[0031] B-S2: Real-time monitor the pH value at the inlet of the coagulation sedimentation tank, the pH value at the inlet of the ozonated activated carbon filter, the pH value at the inlet of the membrane filtration tank, and the turbidity at the outlet of the coagulation sedimentation tank;

[0032] B-S3: Substitute the pH value data in B-S2 into the first deviation relationship curve to obtain the real-time deviation aeration volume of CO in the coagulation sedimentation tank, the ozonated activated carbon filter, and the ultrafiltration membrane filtration tank, and then obtain the real-time corrected aeration volume of CO according to the CO 2 average deviation coefficient; 2 Substitute the turbidity data in B-S2 into the second deviation relationship curve to obtain the real-time deviation dosage of the coagulant, and then calculate the real-time corrected dosage of the coagulant in the coagulation sedimentation tank according to the in-built coagulant average deviation coefficient; 2 real-time corrected aeration volume;

[0033] B-S4: According to the real-time corrected aeration volume of CO and the real-time corrected dosage of the coagulant obtained in B-S3, control the CO emissions in the ozonated activated carbon filter and the ultrafiltration membrane tank, as well as the CO

[0034] emissions in the coagulation sedimentation tank and the dosage of the coagulant. 2 real-time corrected aeration volume and the real-time corrected dosage of the coagulant, control the CO 2 emissions, as well as the CO emissions in the coagulation sedimentation tank 2 emissions and the dosage of the coagulant.

[0035] Furthermore, the acquisition method of the first theoretical relationship curve in Method A is: Using the type A raw water as the water sample, prepare the simulated water sample A with different pH values, introduce CO 2 gas into the simulated water sample A, measure the changes in the pH value and the CO 2 aeration volume, and establish the first theoretical relationship curve between the pH value and the CO 2 aeration volume;

[0036] The method for obtaining the second theoretical relationship curve is as follows: Using the type A raw water as the water sample, adding an aluminum salt coagulant thereto, measuring the changes in turbidity and coagulant dosage, and establishing the second theoretical relationship curve between turbidity and coagulant dosage.

[0037] Further, in B-S1 of method B, the method for obtaining the first deviation relationship curve is as follows: Using the type B raw water as the water sample, aerating CO 2 gas thereto, measuring the changes in pH value and CO 2 aeration volume, and establishing the first deviation relationship curve between pH value and CO 2 aeration volume;

[0038] The method for obtaining the second deviation relationship curve is as follows: Using the type B raw water as the water sample, adding an aluminum salt coagulant thereto, measuring the changes in turbidity and coagulant dosage, and establishing the second deviation relationship curve between turbidity and coagulant dosage.

[0039] Further, in B-S1 of method B, the method for obtaining the average deviation coefficient of CO 2 is as follows:

[0040] Using the up-to-standard effluent of the type B raw water purification treatment as the water sample, establishing the third theoretical relationship curve between pH value and CO 2 aeration volume; Using the type B raw water as the water sample, establishing the first deviation relationship curve between pH value and CO 2 aeration volume;

[0041] According to formula (1), the CO 2 deviation coefficient is calculated;

[0042]

[0043] wherein, represents the average deviation coefficient of CO 2 ; i represents the value of the change in pH value in the simulated water sample A, i decreases from high to low, the initial value of i is the initial pH value of the simulated water sample A, generally 7.5 - 9.0, n is the lowest value after the pH value drops, generally 6.0 - 7.0; N represents the number of measurements of pH and its corresponding CO 2 deviation aeration volume during the process of pH dropping from i to n; Q di represents the CO 2 deviation aeration volume at pH value i, which is obtained through the first deviation relationship curve; Q ti represents the CO 2 theoretical aeration volume at pH value i, which is obtained through the third theoretical relationship curve.

[0044] Further, in B-S1 of Method B, the method for obtaining the average deviation coefficient of the coagulant is as follows:

[0045] Using the up-to-standard effluent of type II raw water purification treatment as the water sample, establish the fourth theoretical relationship curve between turbidity and coagulant dosage; using type II raw water as the water sample, establish the second deviation relationship curve between turbidity and coagulant dosage;

[0046] According to formula (2), calculate the average deviation coefficient of the coagulant;

[0047]

[0048] Among them, δ PAC represents the average deviation coefficient of the coagulant; j represents the value of the turbidity change in simulated water sample A, j decreases from high to low, the initial value of j is the initial turbidity value of simulated water sample I, generally 20.0 - 25.0, m is the lowest value after turbidity reduction, generally 0 - 1.0; M represents the number of measurements of turbidity and its corresponding coagulant dosage during the process of turbidity decreasing from j to m; D di represents the deviation dosage of the coagulant at pH value i; the deviation dosage of the coagulant D di represents the deviation dosage of the coagulant when the turbidity is j in the second deviation relationship curve; D ti represents the theoretical dosage of the coagulant when the turbidity is j.

[0049] Further, in B-S4 of Method B, the calculation formula for the real-time corrected aeration volume of CO 2 is as follows: CO 2 Real-time corrected aeration volume = CO 2 Real-time deviation aeration volume × CO 2 Deviation coefficient;

[0050] The calculation formula for the real-time corrected dosage of the coagulant is: Real-time corrected dosage of the coagulant = Real-time deviation dosage of the coagulant × Average deviation coefficient of the coagulant.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] (1) The urban multi-source water purification system provided by the present invention, through the setting of the control component and in cooperation with the switching pipeline, enables the adjustment of the flow direction of the raw water according to the pH value of the raw water, so that the raw water can select different treatment units. Compared with the existing single raw water combined with the corresponding water purification process, the water purification device of the present application is more flexible and can perform different water purification treatments on the raw water according to the changes of the raw water, thereby improving the water purification effect.

[0053] (2) Through the refined CO of the present invention 2Automated dosing control effectively improves the effect of coagulation and sedimentation, reduces the concentration of aluminum ions in the water body, thereby extending the membrane life and promoting the effective operation of the entire water purification process.

[0054] (3) Improve coagulation efficiency: By precisely controlling the CO 2 dosing and optimizing the pH value, the coagulation efficiency of aluminum salt coagulants is significantly improved, the usage amount of aluminum salt coagulants is reduced, the floc formation time is shortened, and the treatment speed is increased. Description of the Drawings

[0055] Figure 1 It is a schematic diagram of the overall structure of the urban multi-source water purification system of the present invention.

[0056] Figure 2 It is a schematic diagram of the structure of the pre-ozonation treatment tank of the urban multi-source water purification system of the present invention.

[0057] Figure 3 It is a schematic diagram of the structure of the flocculation sedimentation tank of the urban multi-source water purification system of the present invention.

[0058] Figure 4 It is a schematic diagram of the mechanism of an embodiment of the automated process control system.

[0059] Figure 5 It is a schematic diagram of the mechanism of the controller in the automated process control device.

[0060] Figure 6 It is a schematic diagram of the mechanism of the feedback control module in the controller.

[0061] Figure 7 It is a schematic diagram of the process of an embodiment of the control method of the urban multi-source water purification system of the present invention.

[0062] Among them, 1 is the switching pipeline; 11 is the raw water pipe; 12 is the two-way three-way valve; 13 is the first unit pipe; 14 is the second unit pipe; 15 is the first water inlet pipe; 16 is the second water inlet pipe; 2 is the pre-ozonation treatment tank; 22 is the first baffle; 23 is the second baffle; 24 is the ventilation hole; 25 is the ozone inlet pipe; 26 is the ozone aeration head; 27 is the first water passage; 28 is the second water passage; 3 is the coagulation sedimentation tank; 31 is the sedimentation tank body; 32 is the coagulant addition pipe; 33 is the baffle; 34 is the filter installation plate; 4 is the sand filter tank; 5 is the ozone activated carbon tank; 6 is the ultrafiltration membrane tank; 7 is the nanofiltration membrane tank; 8 is the outlet pipeline; 9 is the automated control system; 91 is the water quality sensor; 92 is the CO 2 doser; 93 is the coagulant doser; 94 is the controller; 911 is the water quality monitoring probe; 921 is the CO 2 aeration port; 931 is the coagulant dosing port; 941 is the information acquisition module; 942 is the data processing and analysis module; 943 is the feedback control module; 9431 is the water source switching control sub-module; 9432 is the CO 2Dosing control sub-module; 9433 Coagulant dosing control sub-module; 10 Storage device; 101 Ozone storage tank; 102 Coagulant storage tank; 103 CO 2 Storage tank; 104 Oxygen storage tank. Detailed implementation manners

[0063] To make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the following describes the detailed implementation manners of the high-pH raw water purification control system and the control method in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0064] The type B raw water described in this application refers to raw water with "pH of 7.6 - 8.8; permanganate index of 2.4 - 4.8 mg / L; ammonia nitrogen of 0.1 - 0.6 mg / L; turbidity of 12 - 25 NTU", generally sourced from wetland water, lake water, river water, etc.

[0065] The type A raw water described in this application refers to that, referring to the regulations of type B raw water, if the pH of type I raw water is lower than 7.6 and the turbidity is lower than 12 NTU, it is used as type A raw water for subsequent treatment.

[0066] The up-to-standard effluent of the water treatment described in this application: pH is 6.5 - 7.5; permanganate index is 1.0 - 2.5 mg / L; ammonia nitrogen is 0.04 - 0.1 mg / L; turbidity is 0 - 0.2 NTU.

[0067] As Figure 1 shown, the present invention provides an urban multi-source water purification system, including a switching pipeline, a first treatment unit and a second treatment unit connected to the switching pipeline, a water outlet pipeline provided at the other ends of the first treatment unit and the second treatment unit, and an automated control system.

[0068] Specifically, the switching pipeline includes multiple raw water pipes, two-way three-way valves provided on the raw water pipes, a first unit pipe and a second unit pipe communicated with the two-way three-way valves, a first inlet pipe communicated with the first treatment unit, a second inlet pipe communicated with the second treatment unit, the second inlet pipe is communicated with the second unit pipe, and the first inlet pipe is communicated with the first unit pipe; the two-way three-way valve is connected to the water source switching control sub-module; water quality monitoring probes are provided on all the raw water pipes.

[0069] Specifically, the first treatment unit includes a coagulation sedimentation tank, a sand filter tank, and an ozone activated carbon tank connected in sequence.

[0070] Specifically, the second treatment unit includes a pre-ozonation treatment tank, a coagulation sedimentation tank, a sand filter tank, an ozone activated carbon tank, an ultrafiltration membrane tank, and a nanofiltration membrane tank connected in sequence.

[0071] Specifically, asFigure 2 As shown in Figure 2 , in one embodiment, the pre-ozonation treatment tank 2 includes a pre-ozonation tank body, first baffle plates arranged at equal intervals in the pre-ozonation tank body, second baffle plates arranged in the pre-ozonation tank body and staggered with the first baffle plates, a plurality of ventilation holes provided on the first baffle plates, ozone inlet pipes installed on the ventilation holes, ozone aeration heads installed on both end faces of the first baffle plates and communicated with the ventilation holes, a first water passage formed between the bottom surface of the first baffle plate and the bottom surface of the inner cavity of the pre-ozonation tank body, and a second water passage formed between the top surface of the second baffle plate and the top surface of the pre-ozonation tank body.

[0072] Specifically, as Figure 3 shown in Figure 3 , in one embodiment, the flocculation sedimentation tank 3 includes a sedimentation tank body 31, a coagulant dosing port 931 installed on the sedimentation tank body, a plurality of baffle plates 32 installed staggered in the sedimentation tank body, and a filter installation plate 33 installed on the baffle plates 32 and the sedimentation tank body 31.

[0073] Specifically, the ultrafiltration membrane tank 6 includes an ultrafiltration tank body, an ultrafiltration membrane module installed in the ultrafiltration tank body, an air supply pipe installed on the ultrafiltration tank body, and the bottom of the ultrafiltration membrane module is connected to an outlet pipeline; the nanofiltration membrane tank 7 includes a nanofiltration tank body, a nanofiltration membrane module installed in the nanofiltration tank body, an air supply pipe installed on the nanofiltration tank body, and the bottom of the nanofiltration membrane module is connected to an outlet pipeline; the air supply pipes are all connected with an air pump, and the air inlet end of the air pump is connected with an oxygen storage tank and a CO 2 storage tank; the ends of the air distribution pipes located in the ultrafiltration tank body and the nanofiltration tank body are both arranged in a ring shape around the membrane module.

[0074] Specifically, as Figure 4 shown in Figure 4 , in one embodiment, the automatic control system 9 is composed of a water quality sensor 91, a CO 2 dosing device 92, a coagulant dosing device 93 and a controller 94; the automatic control can adopt a PLC control system or a DCS control system.

[0075] Specifically, the water quality sensor 91 is provided with water quality monitoring probes 911 respectively installed at the inlet of the coagulation sedimentation tank, the outlet of the coagulation sedimentation tank, the outlet of the ozone activated carbon tank, the outlet of the ultrafiltration membrane tank and the outlet of the nanofiltration membrane tank; the CO 2 dosing device 92 is provided with CO 2 aeration ports 921 respectively communicated with the coagulation sedimentation tank, the ozone activated carbon tank, the ultrafiltration membrane tank and the nanofiltration membrane tank; the coagulant dosing device 93 is provided with a coagulant dosing port 931 communicated with the coagulation sedimentation tank.

[0076] Specifically, as Figure 5 and Figure 6As shown, in one embodiment, the controller 94 includes an information acquisition module 941, a data processing and analysis module 942, and a feedback control module 943. The information acquisition module 941 is configured to receive the water quality data information from the water quality monitoring probe 911 and feed back the water quality data information to the data processing and analysis module 942. The data processing and analysis module 942 receives the data information from the information acquisition module 941, determines the water source type, and calculates and corrects the CO 2 aeration volume and coagulant dosage. The feedback control module 943 includes a water source switching control sub-module 9431, a CO 2 dosage control sub-module 9432, and a coagulant dosage control sub-module 9433. The water source switching control sub-module 9431 controls the opening and closing of the switching pipeline. The CO 2 dosage control sub-module 9432 receives the data information from the data processing and analysis module and controls the opening and closing of the aeration port 921 and the gas flow rate of the CO 2 aeration port. The coagulant dosage control sub-module 9433 controls the opening and closing of the coagulant dosing port 931 and the dosing flow rate of the coagulant.

[0077] Specifically, as Figure 1 shown, in one embodiment, a discharging device 10 is further provided in the urban multi-source water purification system. The discharging device 10 includes an ozone storage tank 101, a coagulant storage tank 102, a CO 2 storage tank 103, and an oxygen storage tank 104. Among them, the ozone storage tank 101 is connected to the pre-ozonation treatment tank 2 and the ozone-activated carbon tank 5; the coagulant storage tank 102 is connected to the coagulant dosing port 931 in the coagulation sedimentation tank 3 and is controlled by the coagulant dosing control sub-module 9433; the CO 2 storage tank 103 is respectively connected to the CO 2 aeration ports in the coagulation sedimentation tank 3, the ozone-activated carbon tank 5, the ultrafiltration membrane tank 6, and the nanofiltration membrane tank 7, and can be controlled by the CO 2 dosage control sub-module 9432; the oxygen storage tank 104 is connected to the ultrafiltration membrane tank and the nanofiltration membrane tank.

[0078] As Figure 7 shown, the present invention provides a control method for the above-mentioned urban multi-source water purification system, which is specifically as follows:

[0079] Judge whether the raw water is type A raw water or type B raw water according to the raw water pH value data at the inlet of the coagulation sedimentation tank, and select the treatment method according to the type of the raw water.

[0080] Specifically, the water quality monitoring probe set on the raw water pipe feeds back data to the data processing and analysis module. The data processing and analysis module determines whether the raw water is type A raw water or type B raw water based on the pH value and turbidity of the raw water. When the raw water is type A raw water, the water source switching control sub-module controls the two-way three-way valve to connect the raw water pipe to the first treatment unit, so that the type A raw water is introduced into the first treatment unit for treatment; when the raw water is type B raw water, the water source switching control sub-module controls the two-way three-way valve to connect the raw water pipe to the second treatment unit, so that the type B raw water is introduced into the second treatment unit for treatment.

[0081] The first treatment unit adopts control method A, including:

[0082] A-S1: Using type A raw water as a water sample, obtaining the first theoretical relationship curve between the pH value and the CO 2 aeration volume, and the second theoretical relationship curve between the turbidity and the coagulant dosage.

[0083] Specifically, in control method A, in A-S1, the acquisition method of the first theoretical relationship curve is: using type A raw water as a water sample, preparing simulated water sample A with different pH values, introducing CO 2 gas into the simulated water sample A, measuring the changes in the pH value and the CO 2 aeration volume, and establishing the first theoretical relationship curve between the pH value and the CO 2 aeration volume; the acquisition method of the second theoretical relationship curve is: using type A raw water as a water sample, adding an aluminum salt-based coagulant to it, measuring the changes in the turbidity and the coagulant dosage, and establishing the second theoretical relationship curve between the turbidity and the coagulant dosage.

[0084] Specifically, in control method A, the above first theoretical relationship curve and second theoretical relationship curve need to be input into the data processing and analysis module before the system runs.

[0085] A-S2: Real-time monitoring of the pH value at the inlet of the coagulation sedimentation tank, the pH value at the inlet of the ozonated activated carbon tank, and the turbidity at the outlet of the coagulation sedimentation tank.

[0086] A-S3: Retrieving the pH value data of A-S2, and obtaining the values inside the coagulation sedimentation tank and the ozonated activated carbon tank according to the first theoretical relationship curve; retrieving the turbidity data of A-S2, and obtaining the real-time coagulant dosage inside the coagulation sedimentation tank according to the second theoretical relationship curve.

[0087] Specifically, in the control method of the urban multi-source water purification system, the required turbidity of the final effluent is 0 - 0.2 NTU. Therefore, it is set in the data processing and analysis module that the turbidity of the effluent from the coagulation sedimentation tank is reduced to 0.1 NTU, and the real-time coagulant dosage inside the coagulation sedimentation tank is obtained according to the second theoretical relationship curve in combination with the raw water turbidity during actual use.

[0088] Specifically, in the control method of the urban multi-source water purification system, it is set in the data processing and analysis module that the pH value in the coagulation sedimentation tank is reduced to 7. During actual use, in combination with the pH value of the water inlet of the coagulation sedimentation tank and according to the first theoretical relationship curve, the CO 2 Real-time aeration volume.

[0089] Specifically, in the control method of the urban multi-source water purification system, it is set in the data processing and analysis module that the pH value of the water in the ozone-activated carbon tank is maintained at 7. During actual use, in combination with the pH value of the water inlet of the ozone-activated carbon tank and according to the first theoretical relationship curve, the CO 2 Real-time aeration volume.

[0090] A-S4: According to the CO obtained in A-S3 2 Real-time aeration volume and real-time coagulant addition amount, control the CO emissions in the ozone-activated carbon tank 2 And the CO emissions in the coagulation sedimentation tank 2 Emissions and coagulant dosage.

[0091] Specifically, input the turbidity data of the raw water, the pH value of the water inlet of the coagulation sedimentation tank obtained in A-S2, and the pH value of the water inlet of the ozone-activated carbon tank into the data processing and analysis module. The data processing and analysis module obtains the CO in the coagulation sedimentation tank according to the pre-input first theoretical relationship curve and second theoretical relationship curve 2 Real-time aeration volume, the CO in the ozone-activated carbon tank 2 Real-time aeration volume, the real-time coagulant dosage in the coagulation sedimentation tank and output to the feedback control module to control the CO 2 Dosing equipment, coagulant dosing equipment for CO 2 And the dosing of coagulant.

[0092] The second treatment unit adopts control method B, including:

[0093] B-S1: Set the following data information in the automatic control system:

[0094] 1) The first deviation relationship curve between the pH value and the CO 2 Aeration volume;

[0095] 2) The CO 2 Average deviation coefficient;

[0096] 3) The second deviation relationship curve between the turbidity and the coagulant addition amount;

[0097] 4) Coagulant average deviation coefficient;

[0098] Among them, the method for obtaining the first deviation relationship curve is as follows: Using the type B raw water as the simulated water sample B, taking the simulated water sample B, and aerating CO 2 gas into it, measuring the changes in the pH value and the CO 2 aeration volume, and establishing the first deviation relationship curve between the pH value and the CO 2 aeration volume;

[0099] The method for obtaining the second deviation relationship curve is as follows: Taking the simulated water sample B, adding an aluminum salt-based coagulant to it, measuring the changes in the turbidity and the coagulant dosage, and establishing the second deviation relationship curve between the turbidity and the coagulant dosage.

[0100] CO 2 The method for obtaining the average deviation coefficient is as follows:

[0101] Using the up-to-standard effluent from the purification treatment of the type B raw water as the water sample, establishing the third theoretical relationship curve between the pH value and the CO 2 aeration volume; Using the type B raw water as the water sample, establishing the first deviation relationship curve between the pH value and the CO 2 aeration volume;

[0102] According to formula (1), calculate the CO 2 deviation coefficient;

[0103]

[0104] Among them, represents the CO 2 average deviation coefficient; A represents the numerical value of the change in the pH value in the simulated water sample A. A decreases from high to low. The initial value of A is the initial pH value of the simulated water sample A, generally 7.5 - 9.0. n is the lowest value after the pH value drops, generally 6.0 - 7.0; N represents the number of measurements of the pH and its corresponding CO 2 deviation aeration volume during the process of the pH dropping from A to n; Q di represents the CO 2 deviation aeration volume when the pH value is A, which is obtained through the first deviation relationship curve; Q ti represents the CO 2 theoretical aeration volume when the pH value is A, which is obtained through the third theoretical relationship curve.

[0105] The method for obtaining the coagulant average deviation coefficient is as follows:

[0106] Using the up-to-standard effluent from the purification treatment of the type B raw water as the water sample, establishing the fourth theoretical relationship curve between the turbidity and the coagulant dosage, and establishing the fifth theoretical relationship curve between the Al 3+ concentration and the coagulant dosage; Using the type B raw water as the water sample, establishing the second deviation relationship curve between the turbidity and the coagulant dosage;

[0107] According to formula (2), the average deviation coefficient of the coagulant is calculated;

[0108]

[0109] where δ PAC represents the average deviation coefficient of the coagulant; j represents the value of the turbidity change in simulated water sample A. j decreases from high to low. The initial value of j is the initial turbidity value of simulated water sample A, generally 20.0 - 25.0. m is the lowest value after the turbidity drops, generally 0 - 1.0; M represents the number of measurements of the turbidity and its corresponding coagulant dosage during the process of the turbidity dropping from j to m; D dA represents the deviation dosage of the coagulant with a pH value of A; the deviation dosage of the coagulant D dA represents the deviation dosage of the coagulant when the turbidity is j in the second deviation relationship curve; D tA represents the theoretical dosage of the coagulant when the turbidity is j.

[0110] B-S2: Real-time monitor the pH value at the inlet of the coagulation sedimentation tank, the pH value at the inlet of the ozonated activated carbon tank, the pH value at the inlet of the membrane filtration tank, and the turbidity at the outlet of the coagulation sedimentation tank.

[0111] The acquisition methods of the pH value and turbidity data in B-S2 are the same as those in A-S2.

[0112] B-S3: Substitute the pH value data of B-S2 into the first deviation relationship curve to obtain the real-time deviation aeration volume of CO in the coagulation sedimentation tank, the ozonated activated carbon tank, the ultrafiltration membrane tank, and the nanofiltration membrane tank. Then, according to the average deviation coefficient of CO 2 obtain the real-time corrected aeration volume of CO 2 ; 2 Substitute the turbidity data of B-S2 into the second deviation relationship curve to obtain the real-time deviation addition amount of the coagulant. Then, according to the internally set average deviation coefficient of the coagulant, calculate the real-time corrected addition amount of the coagulant in the coagulation sedimentation tank;

[0113] B-S4: According to the real-time corrected aeration volume of CO and the real-time corrected addition amount of the coagulant obtained in B-S3, control the emissions of CO in the ozonated activated carbon tank, the ultrafiltration membrane tank, and the nanofiltration membrane tank, as well as the emissions of CO in the coagulation sedimentation tank and the dosage of the coagulant.

[0114] Specifically, in B-S4, the calculation formula for the real-time corrected aeration volume of CO 2 is: Real-time corrected aeration volume of CO 2 = 2 ;

[0115] Specifically, in B-S4, the calculation formula for the real-time corrected aeration volume of CO 2 is: Real-time corrected aeration volume of CO 2 Real-time corrected aeration volume of CO =2 Real-time deviation aeration volume × CO 2 Deviation coefficient; the calculation formula for the real-time corrected dosage of the coagulant is: Real-time corrected dosage of the coagulant = Real-time deviation dosage of the coagulant × Average deviation coefficient of the coagulant.

[0116] Specifically, the turbidity data of the raw water, the pH value at the inlet of the coagulation sedimentation tank obtained by B-S2, the pH value at the inlet of the ozonated activated carbon tank, the pH value at the inlet of the ultrafiltration membrane tank, and the turbidity at the outlet of the coagulation sedimentation tank are input into the data processing and analysis module. The data processing and analysis module obtains the CO in the coagulation sedimentation tank according to the pre-input first deviation relationship curve and second deviation relationship curve. 2 Real-time aeration volume, CO in the ozonated activated carbon tank 2 Real-time aeration volume, CO in the ultrafiltration membrane tank 2 Real-time aeration volume, real-time dosage of the coagulant in the coagulation sedimentation tank and output to the feedback control module to control CO 2 Dosing equipment, coagulant dosing equipment for CO 2 And the dosing of the coagulant.

[0117] During the treatment process of the raw water controlled by control method A or control method B, the Al concentration at the outlet of the ozonated activated carbon tank is monitored in real time. 3+ If the Al concentration 3+ is 0.05 - 0.2 mg / L, the water discharged from the aerated ozonated activated carbon tank is re-circulated to the coagulation sedimentation tank.

[0118] Specifically, after the water body is treated by the first treatment unit or the second treatment unit, it flows out of the treatment device through the outlet pipeline 8.

[0119] The specific situation of the present invention controlling the urban multi-source water purification system for water treatment by the above control method is as follows:

[0120] For a certain waterworks in a certain city, the raw water of this waterworks comes from urban wetland water and lakes. In August, the water quality is: pH is 7.8 - 8.4; permanganate index is 2.8 - 3.8 mg / L; ammonia nitrogen is 0.1 - 0.3 mg / L; turbidity is 13.5 - 17.8 NTU. Through the water purification system and its supporting control method of the present application, the CO 2 aeration volume can be reduced from the original 13 mg / L to 9 mg / L, the dosage of the coagulant is reduced by 25% - 35%, and finally the water purification efficiency can be increased by 15% - 20%; the quality of the treated water is pH is 6.8 - 7.5; permanganate index is 1.4 - 1.9 mg / L; ammonia nitrogen is 0.04 - 0.07 mg / L; turbidity is 0 - 0.12 NTU.

[0121] Also for this waterworks, in December, the water quality was as follows: pH was 7.1 - 7.5; permanganate index was 2.3 - 3.1 mg / L; ammonia nitrogen was 0.1 - 0.2 mg / L; turbidity was 7.3 - 9.8 NTU. Through the water purification system of the present application and its supporting control method, the effluent water quality was: pH was 6.8 - 7.2; permanganate index was 0.9 - 1.5 mg / L; ammonia nitrogen was 0.02 - 0.05 mg / L; turbidity was 0 - 0.10 NTU.

[0122] The specific embodiments described above have elaborated on the technical solutions and beneficial effects of the present invention. It should be understood that the above is only the most preferred embodiment of the present invention and is not used to limit the present invention. Any modifications, supplements, equivalent replacements, etc. made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An urban multi-source water purification system, characterized in that: include: A switching pipeline, a first treatment unit and a second treatment unit connected to the switching pipeline, a water outlet pipeline arranged on the other ends of the first treatment unit and the second treatment unit, and an automatic control system; the first treatment unit includes a coagulation sedimentation tank, a sand filter tank and an ozone activated carbon tank connected in sequence; the second treatment unit includes a pre-ozonation treatment tank, a coagulation sedimentation tank, a sand filter tank, an ozone activated carbon tank, an ultrafiltration membrane tank and a nanofiltration membrane tank connected in sequence; The automatic control system includes a water quality sensor, a CO2 dosing device, a coagulant dosing device and a controller; the water quality sensor is provided with water quality monitoring probes respectively installed at the water inlet of the coagulation sedimentation tank, the water outlet of the coagulation sedimentation tank, the outlet of the ozone activated carbon tank, the outlet of the ultrafiltration membrane tank and the outlet of the nanofiltration membrane tank; the CO2 dosing device is provided with a CO2 aeration port respectively connected to the coagulation sedimentation tank, the ozone activated carbon tank, the ultrafiltration membrane tank and the nanofiltration membrane tank; the coagulant dosing device is provided with a coagulant dosing port connected to the coagulation sedimentation tank; The controller includes an information acquisition module, a data processing and analysis module and a feedback control module; the information acquisition module is used to receive water quality data information from the water quality monitoring probe and feed back the water quality data information to the data processing and analysis module; the data processing and analysis module receives the data information from the information acquisition module, determines the water source type, and calculates and corrects the CO2 aeration amount and the coagulant addition amount; the feedback control module includes a water source switching control submodule, a CO2 addition control submodule and a coagulant addition control submodule; the water source switching control submodule controls the opening and closing of the switching pipeline; the CO2 addition control submodule receives the data information from the data processing and analysis module, controls the opening and closing of the CO2 aeration port and the gas flow rate; the coagulant addition control submodule controls the opening and closing of the coagulant addition port and the coagulant addition flow rate.

2. The urban multi-source water purification system according to claim 1, characterized in that: The switching pipeline includes multiple raw water pipes, a two-position three-way valve arranged on the raw water pipe, a first unit pipe and a second unit pipe connected to the two-position three-way valve, a first water inlet pipe connected to the first treatment unit, a second water inlet pipe connected to the second treatment unit, the second water inlet pipe is connected to the second unit pipe, and the first water inlet pipe is connected to the first unit pipe; the two-position three-way valve is connected to the water source switching control submodule; and water quality monitoring probes are provided on the raw water pipes.

3. The urban multi-source water purification system according to claim 1, characterized in that: The pre-ozone treatment tank includes a pre-ozone tank body, a first baffle plate arranged in the pre-ozone tank body at equal intervals, a second baffle plate arranged in the pre-ozone tank body and staggered with the first baffle plate, a plurality of vents are arranged on the first baffle plate, an ozone air inlet pipe is installed on the vents, an ozone aeration head is installed on both end surfaces of the first baffle plate and connected to the vents, a first water passage is formed between the bottom surface of the first baffle plate and the bottom surface of the inner cavity of the pre-ozone tank body, and a second water passage is formed between the top surface of the second baffle plate and the top surface of the pre-ozone tank body.

4. The urban multi-source water purification system according to claim 1, characterized in that: The ultrafiltration membrane pool comprises an ultrafiltration pool body, an ultrafiltration membrane assembly installed in the ultrafiltration pool body, and an aeration pipe installed on the ultrafiltration pool body, and the bottom of the ultrafiltration membrane assembly is connected to the water outlet pipeline; The nanofiltration membrane pool comprises a nanofiltration membrane pool body, a nanofiltration membrane assembly installed in the nanofiltration membrane pool body, and an aeration pipe installed on the nanofiltration membrane pool body, and the bottom of the nanofiltration membrane assembly is connected to the water outlet pipeline; The aeration pipe is connected to an aeration pump, and the air inlet end of the aeration pump is connected to an oxygen storage tank and a CO2 storage tank; The ends of the aeration branch pipes located in the ultrafiltration tank body and the nanofiltration membrane tank body are both arranged in a ring shape around the membrane assembly.

5. A method for treating raw water using the urban multi-source water purification system according to any one of claims 1 to 4, characterized in that: include: (1) Monitor the water quality of the raw water pipe and determine whether the raw water type is type A or type B. The water source switching control submodule controls type A raw water to enter the first treatment unit and type B raw water to enter the second treatment unit; the first treatment unit uses method A to treat the water quality, and the second treatment unit uses method B to treat the water quality; The water quality criteria for Type A raw water are: pH below 7.6, turbidity below 12 NTU; raw water with other water quality conditions is considered Type B raw water; Method A: A-S1: Using type A raw water as the water sample, obtain the first theoretical relationship curve between pH value and CO2 aeration amount, and the second theoretical relationship curve between turbidity and coagulant addition amount; A-S2: Real-time monitoring of the pH value and turbidity of the water inlet of the coagulation sedimentation tank, the pH value of the water inlet of the ozone activated carbon filter, and the turbidity of the water outlet of the coagulation sedimentation tank; A-S3: Retrieve the pH value data of A-S2, and obtain the real-time aeration volume of CO2 in the coagulation sedimentation tank, the ozone activated carbon filter tank, and the ultrafiltration membrane filter tank according to the first theoretical relationship curve; retrieve the turbidity data of A-S2, and obtain the real-time addition amount of coagulant in the coagulation sedimentation tank according to the second theoretical relationship curve; A-S4: According to the real-time aeration volume of CO2 and the real-time addition volume of coagulant obtained in A-S3, the emission of CO2 in the ozone activated carbon filter and the ultrafiltration membrane filter, as well as the emission of CO2 and the dosage of coagulant in the coagulation sedimentation tank are controlled; Method B: B-S1: Get the following data information: 1) Using type B raw water as a water sample, obtain a first deviation relationship curve between pH value and CO2 aeration amount; 2) CO2 average deviation coefficient; 3) Using type B raw water as a water sample, obtaining a second deviation relationship curve between turbidity and the amount of coagulant added; 4) Average coefficient of deviation of coagulant; B-S2: Real-time monitoring of the pH value at the inlet of the coagulation sedimentation tank, the pH value at the inlet of the ozone activated carbon filter, the pH value at the inlet of the membrane filter, and the turbidity at the outlet of the coagulation sedimentation tank; B-S3: Substitute the pH value data of B-S2 into the first deviation relationship curve to obtain the real-time deviation aeration volume of CO2 in the coagulation sedimentation tank, the ozone activated carbon filter tank and the ultrafiltration membrane filter tank, and then obtain the real-time corrected aeration volume of CO2 based on the average deviation coefficient of CO2; Substitute the turbidity data of B-S2 into the second deviation relationship curve to obtain the real-time deviation addition amount of the coagulant, and then calculate the real-time correction addition amount of the coagulant in the coagulation sedimentation tank according to the internal coagulant average deviation coefficient; B-S4: According to the real-time CO2 correction aeration volume and real-time coagulant correction addition volume obtained in B-S3, the CO2 emission in the ozone activated carbon filter and ultrafiltration membrane pool, as well as the CO2 emission and coagulant dosage in the coagulation sedimentation tank are controlled.

6. The method according to claim 5, characterized in that The first theoretical relationship curve in method A is obtained by: using type A raw water as a water sample, preparing simulated water samples A with different pH values, exposing CO2 gas to the simulated water samples A, measuring the changes in pH value and CO2 aeration amount, and establishing the first theoretical relationship curve between pH value and CO2 aeration amount; The second theoretical relationship curve is obtained by taking type A raw water as a water sample, adding an aluminum salt coagulant thereto, measuring the changes in turbidity and the amount of coagulant added, and establishing the second theoretical relationship curve between turbidity and the amount of coagulant added.

7. The method according to claim 6, characterized in that In B-S1 of method B, the method for obtaining the first deviation relationship curve is: using type B raw water as a water sample, exposing CO2 gas thereto, measuring the changes in pH value and CO2 aeration amount, and establishing a first deviation relationship curve between pH value and CO2 aeration amount; The method for obtaining the second deviation relationship curve is: using type B raw water as a water sample, adding an aluminum salt coagulant thereto, measuring changes in turbidity and the amount of coagulant added, and establishing a second deviation relationship curve between turbidity and the amount of coagulant added.

8. The method according to claim 7, characterized in that In B-S1 of Method B, the method for obtaining the CO2 average deviation coefficient is: The third theoretical relationship curve between pH value and CO2 aeration volume was established by taking the qualified effluent of type B raw water purification treatment as the water sample; the first deviation relationship curve between pH value and CO2 aeration volume was established by taking type B raw water as the water sample; According to formula (1), the CO2 deviation coefficient is calculated; in, It represents the average deviation coefficient of CO2; i represents the value of the change of pH value in the simulated water sample A, i is from high to low, the initial value of i is the initial pH value of the simulated water sample A, generally 7.5-9.0, n is the lowest value after the pH value drops, generally 6.0-7.0; N represents the number of measurements of pH and its corresponding CO2 deviation aeration volume in the process of pH dropping from i to n; Q di represents the CO2 deviation aeration volume when the pH value is i, which is obtained through the first deviation relationship curve; Q ti It represents the theoretical aeration rate of CO2 when the pH value is i, which is obtained through the third theoretical relationship curve.

9. The method according to claim 8, characterized in that In B-S1 of Method B, the method for obtaining the average deviation coefficient of the coagulant is: The fourth theoretical relationship curve between turbidity and the amount of coagulant added was established by taking the qualified effluent of Type II raw water purification treatment as the water sample; the second deviation relationship curve between turbidity and the amount of coagulant added was established by taking Type II raw water as the water sample; According to formula (2), the average deviation coefficient of coagulant is calculated; Among them, δ PAC Indicates the average deviation coefficient of the coagulant; j indicates the value of the turbidity change in the simulated water sample A, j is from high to low, the initial value of j is the initial turbidity value of the simulated water sample I, generally 20.0-25.0, m is the lowest value after the turbidity decreases, generally 0-1.0; M indicates the number of times the turbidity and its corresponding coagulant dosage are measured in the process of the turbidity decreasing from j to m; D di Indicates the deviation dosage of coagulant at pH value i; deviation dosage of coagulant D di Indicates the deviation dosage of coagulant when the turbidity is j in the second deviation relationship curve; D ti It indicates the theoretical dosage of coagulant when the turbidity is j.

10. The method according to claim 9, characterized in that In B-S4 of method B, the calculation formula of CO2 real-time corrected aeration volume is: CO2 real-time corrected aeration volume = CO2 real-time deviation aeration volume × CO2 deviation coefficient; The calculation formula for the real-time correction addition amount of coagulant is: real-time correction addition amount of coagulant = real-time deviation addition amount of coagulant × average deviation coefficient of coagulant.

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