Pre-advanced oxidation treatment system for raw drinking water

Abstract

The utility model relates to the field of drinking water raw water pretreatment, in particular to a drinking water raw water pre-advanced oxidation treatment system which comprises a first pipeline mixer, a second pipeline mixer and neutralization equipment, drinking water raw water is subjected to pre-advanced oxidation treatment, refractory organic pollutants are removed, and then the drinking water raw water is conveyed to a subsequent treatment unit. A first pipeline mixer in the system is provided with an acidifying agent conveying device, a ferrous salt conveying device and a connecting pipeline, so that an acidic condition is created for Fenton reaction; the second pipeline mixer is provided with hydrogen peroxide conveying equipment and a connecting pipeline and is used for Fenton reaction; the neutralization equipment is provided with neutralizer conveying equipment and a connecting pipeline, and the pH value of the raw water subjected to the Fenton reaction is adjusted to be within the specified standard. According to the first pipeline mixer and the second pipeline mixer adopted by the invention, the Fenton oxidation reaction process is set in the pipeline conveying process, so that the use of tower equipment and reaction tanks is reduced, and the equipment and land cost is effectively reduced.

Description

Technical Field

[0001] The present application relates to the field of pretreatment of raw water for drinking water, and specifically relates to a pre-advanced oxidation treatment system for raw water of drinking water. Background Art

[0002] As a commonly used wastewater treatment technology, the Fenton oxidation process is simple to operate and has strong applicability, so it has been widely used. When this process is used for the pretreatment of raw water for drinking water, it can not only remove organic pollutants in the water, but also greatly improve the subsequent coagulation effect. The Fenton pre-oxidation technology is based on the Fenton reaction. Under acidic conditions, hydroxyl radicals ·OH with strong oxidizing properties generated by the reaction of ferrous ions Fe 2+ and hydrogen peroxide H 2 O 2 , as well as other reactive oxygen species generated thereby, achieve the removal of refractory organic pollutants in the raw water. At the same time, ferrous ions Fe 2+ can be converted into ferric ions Fe 3+ with coagulation and precipitation effects, which helps with subsequent coagulation and precipitation treatment.

[0003] The traditional Fenton pre-oxidation technology uses a reaction tower or a reaction tank for the Fenton oxidation reaction, which has high equipment costs and large floor areas. Therefore, there is an urgent need to design a pre-advanced oxidation treatment system for raw water of drinking water equipped with a Fenton reaction device to solve the above problems. Utility Model Content

[0004] The purpose of the present utility model is to provide a pre-advanced oxidation treatment system for raw water of drinking water, which solves the problems of high equipment costs and large floor areas mentioned in the above background art by setting the Fenton oxidation reaction during the pipeline transportation process.

[0005] To achieve the above purpose, the present utility model provides the following technical solutions:

[0006] A pre-advanced oxidation treatment system for raw water of drinking water includes a first pipeline mixer, a second pipeline mixer, a neutralization device, a raw material conveying device, and connecting pipelines connecting the above parts; the raw material conveying device includes an acidifying agent conveying device, a ferrous salt conveying device, a hydrogen peroxide conveying device, and a neutralizing agent conveying device; the first pipeline mixer is connected to the acidifying agent conveying device and the ferrous salt conveying device; the second pipeline mixer is connected to the first pipeline mixer and the hydrogen peroxide conveying device; the neutralization device is connected to the second pipeline mixer and the neutralizing agent conveying device. This pre-advanced oxidation treatment system for raw water of drinking water sets the Fenton oxidation reaction during the pipeline transportation process. On the premise of ensuring the Fenton effect, the use of tower equipment and reaction tanks is reduced, and the equipment and land costs are lowered.

[0007] Preferably, the acidifying agent delivery device includes a carbon dioxide feeding device, and the carbon dioxide feeding device is connected to the first pipeline mixer, effectively reducing the difficulty of regulating the pH of the system. Even if an excessive amount is added, it will not cause the pH of the raw water to be too low.

[0008] More preferably, the acidifying agent delivery device includes a hydrochloric acid feeding pump, and the hydrochloric acid feeding pump is connected to the first pipeline mixer. When the carbon dioxide in the raw water reaches saturation, the pH of the solution is further reduced relatively gently to the specified range.

[0009] More preferably, the neutralizing agent delivery device includes a lime feeding pump, and the lime feeding pump is connected to the neutralizing device, thereby enhancing the calcium hardness of the water quality and improving the chemical stability of the effluent water.

[0010] Preferably, the pre-advanced oxidation treatment system for drinking water raw water includes a pH on-line detector. The pH on-line monitor includes a pH sensor and a secondary instrument, and the pH sensor is connected to the secondary instrument; the pH sensor is composed of a first pH sensor disposed inside the first pipeline mixer and a second pH sensor disposed inside the neutralizing device, meeting the real-time monitoring requirements of the pH change in the system.

[0011] More preferably, the pH sensor is a differential pH sensor, effectively improving the accuracy of pH monitoring in a polluted environment.

[0012] Preferably, the pre-advanced oxidation treatment system for drinking water raw water includes an automatic feeding system. The automatic feeding system includes a lower computer PLC cabinet, an upper computer industrial computer, and a frequency converter; the frequency converter includes a first frequency converter connected to the acidifying agent delivery device and a second frequency converter connected to the neutralizing agent delivery device; the lower computer PLC cabinet is respectively connected to the upper computer industrial computer, the first frequency converter, the second frequency converter, and the pH sensor, thereby realizing the automatic control of the pH adjustment in the system.

[0013] Preferably, the pre-advanced oxidation treatment system for drinking water raw water includes an emergency feeding system. The emergency feeding system includes a power-off detection device, a signal transmission device, a feeding device, and a storage device; the power-off detection device is connected to the feeding device through the signal transmission device; the feeding device is connected to the storage device, the first pipeline mixer, the second pipeline mixer, and the neutralizing device. The emergency feeding system realizes the continuous addition of raw materials during power failure, avoids unqualified effluent water quality, and leaves time for employees' emergency treatment.

[0014] More preferably, the power-off detection device, the signal transmission device, and the feeding device are specifically power-off opening solenoid valves; the power-off opening solenoid valves are arranged among the connecting pipelines where the storage device is respectively connected to the first pipeline mixer, the second pipeline mixer, and the neutralization device. Using power-off opening solenoid valves can simultaneously complete power-off detection and feeding, simplify the system structure, and reduce the equipment cost.

[0015] Preferably, the inner walls of the first pipeline mixer, the second pipeline mixer, and the connecting pipelines are all coated with an anti-corrosion coating and / or provided with an anti-corrosion lining to weaken the corrosion degree inside the pipeline, extend the service life, and improve the safety of the working environment.

[0016] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0017] (1) The present utility model is provided with a first pipeline mixer, a second pipeline mixer, and related connecting pipelines for treating raw drinking water. Among them, the first pipeline mixer is used to create an acidic reaction environment, and the second pipeline mixer and related connecting pipelines are the main places for the Fenton reaction to occur. The combined use of the two pipeline mixers ensures the generation of hydroxyl radicals and other reactive oxygen species, enabling the effective removal of refractory organic pollutants in the raw water, achieving the same effect as a tower device or a reaction tank. In addition, the pipe structure of the pipeline mixer usually has a much lower cost than that of a reaction tower or a reaction tank, reducing the equipment input cost. Moreover, the pipeline mixer does not require a large volume and can be directly installed on the pipeline without occupying land. It can be expected that in actual applications, it can be set at a safe pipe section position according to the installation situation of other equipment in the water plant. Therefore, the present utility model arranges the Fenton oxidation reaction process during the pipeline transportation process, reduces the use of tower devices and reaction tanks, and reduces the equipment and land use costs on the premise of ensuring the removal effect of the Fenton reaction on refractory organic pollutants.

[0018] (2) The present utility model adopts an automatic feeding system, which can quickly and accurately adjust the raw material addition amount according to the real-time monitored pH data, realizing the automatic control of the system pH.

[0019] (3) The present utility model is provided with an emergency feeding system, which can ensure the stable production of qualified drinking water during power failure. Description of the Drawings

[0020] Figure 1 It is a diagram of a pre-advanced oxidation treatment system for raw drinking water;

[0021] Figure 2 It is a diagram of a pre-advanced oxidation treatment system for raw drinking water with automatic feeding;

[0022] Figure 3It is a diagram of a drinking water raw water pre - advanced oxidation treatment system with emergency feeding function.

[0023] Description of reference numerals:

[0024] 1 - First pipeline mixer; 2 - Second pipeline mixer; 3 - Neutralization equipment;

[0025] 41 - Acidifying agent delivery equipment; 42 - Ferrous salt delivery equipment; 43 - Hydrogen peroxide delivery equipment; 44 - Neutralizing agent delivery equipment;

[0026] 5 - pH on - line monitor;

[0027] 61 - Lower - level PLC cabinet; 62 - Upper - level industrial computer; 63 - First frequency converter; 64 - Second frequency converter;

[0028] 71 - Storage device; 72 - Power - off opening type solenoid valve. Specific implementation mode

[0029] The technical solution of this patent will be further described in detail below in combination with specific implementation modes.

[0030] In this article, terms such as "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0031] After the natural water from groundwater and rivers, lakes and reservoirs enters the drinking water plant, it is transported to the drinking water raw water pre - advanced oxidation treatment system. The acidifying agent in this system adjusts the pH of the system to 4.5 to 6.5, creating the required acidic environment for the Fenton reaction. In addition, the addition of ferrous salt (with a content of 1 mg / L to 20 mg / L, calculated as Fe 2+ also further reduces the pH to 3.5 to 4.5. Hydrogen peroxide (with a content of 2 mg / L to 40 mg / L, calculated as H 2 O 2 reacts with ferrous ions under acidic conditions to generate ·OH, reducing the content of refractory organic matter in the system. Then, a neutralizing agent is used to adjust the environmental pH to 6.5 to 8.5 and send it to the subsequent treatment unit.

[0032] Example 1:

[0033] Referring to the appendix Figure 1 , a drinking water raw water pre - advanced oxidation treatment system includes a first pipeline mixer 1, a second pipeline mixer 2, a neutralization equipment 3, a raw material delivery device 4, and connecting pipelines connecting the above - mentioned parts.

[0034] (1) The raw material conveying device 4 includes an acidifying agent conveying device 41, a ferrous salt conveying device 42, a hydrogen peroxide conveying device 43, and a neutralizing agent conveying device 44.

[0035] (2) The first pipeline mixer 1 includes a first mixing pipeline, a first feeding port, and a second feeding port. Both feeding ports are connected to the first mixing pipeline. The first feeding port is connected to the acidifying agent conveying device 41, and the second feeding port is connected to the ferrous salt conveying device 42. The first mixing pipeline mixes the acidifying agent, ferrous salt, and raw drinking water.

[0036] Except for the main raw material Fe for the Fenton reaction 2+ In addition, iron ions can also promote the Fenton oxidation reaction to a certain extent. Copper ions, chloride ions, and dihydrogen phosphate will react with ·OH and inhibit the Fenton reaction to a certain extent. Therefore, compared with the ferrous chloride feeding pump, the ferrous sulfate feeding pump with low price and better effect can be selected as the ferrous salt conveying device 42 in industry, and iron ions can be appropriately introduced.

[0037] The acidifying agent conveying device 41 can adopt a carbon dioxide feeding device to add the purified carbon dioxide from industrial tail gas into the system in different forms, which helps to reduce carbon emissions. The carbon dioxide feeding device can adopt a gas feeding form. After gasifying the liquid carbon dioxide, it is dissolved in water by using a pressurizing system. It can also adopt a liquid feeding method to directly inject the carbon dioxide gas into water after converting it into carbonic acid to adjust the pH of the system. Among them, using the carbon dioxide solution feeding avoids the re - return of carbon dioxide to the atmosphere and improves the efficiency of the equipment.

[0038] In addition, a carbon dioxide feeding device and a hydrochloric acid feeding pump can be jointly used as the acidifying agent conveying device 41, and carbon dioxide and hydrochloric acid are added into the system through the first feeding port. The carbon dioxide gas from the carbon dioxide feeding device reacts with water to form carbonic acid, which undergoes hydrolysis and ionization to form carbonate and bicarbonate for the slow regulation of the system pH. Even if an excessive amount is added, it will not cause the pH of the raw water to be too low. If carbon dioxide is continuously introduced but the system pH still does not decrease, it indicates that the carbon dioxide in it has reached saturation. At this time, determine whether the pH falls within the set range. If the pH is still higher than this range, the hydrochloric acid feeding pump can be controlled to supplement hydrochloric acid into the first pipeline mixer 1 to continue reducing the pH to the specified range. Hydrochloric acid, as a supplementary catalyst, introduces chloride ions, but the chloride ion concentration in the system is low, and the consumption of ·OH is not obvious. Therefore, compared with the heat release and strong harm to the human body caused by diluting concentrated sulfuric acid, hydrochloric acid is a better choice.

[0039] (3) The second pipeline mixer 2 includes a second mixing pipeline and a third feeding port. The second mixing pipeline is connected to the first mixing pipeline, and the third feeding port connects the second mixing pipeline with the hydrogen peroxide delivery device 43.

[0040] Both the second pipeline mixer 2 and the connecting pipeline between the second pipeline mixer 2 and the neutralization device 3 are Fenton reaction sites, and the reaction hydraulic retention time is greater than 20 s to ensure its oxidation effect.

[0041] (4) The neutralization device 3 connects the second pipeline mixer 2 and the subsequent treatment unit, and is provided with a fourth feeding port, which is connected to the neutralizing agent delivery device 44.

[0042] The neutralization device 3 can adopt a water distribution well with a mixer. The raw water after the Fenton reaction is collected, a neutralizing agent is added, and the reaction is fully carried out under the drive of the mixer, so as to stabilize the pH of the system within the set range. At the same time, it can also reduce the impact on the subsequent treatment unit caused by the flow rate change.

[0043] The neutralizing agent delivery device 44 can adopt a lime feeding pump, and the lime milk (with a content of 1 mg / L to 20 mg / L, calculated as calcium hydroxide) in the pump is added to the system through the fourth feeding port. On the one hand, the lime milk can adjust the environmental pH, and on the other hand, it can form calcium carbonate with the carbonate ions in the system to enhance the calcium hardness of the water quality and further improve the chemical stability of the produced water.

[0044] In addition, a single-screw pump can be used as the lime feeding pump, which has small mechanical properties, no pulsation, and stable operation, and is very suitable for transporting lime milk containing suspended solids or small solid particles.

[0045] (5) The inner walls of the first pipeline mixer 1, the second pipeline mixer 2 and the connecting pipelines are all coated with an anti-corrosion coating and provided with an anti-corrosion lining.

[0046] The liquid components transported inside the pipeline are relatively complex, so the anti-corrosion measures adopted should be compatible. For example, the peroxy bond of hydrogen peroxide brings strong oxidizing property and extremely high reaction activity. When selecting the anti-corrosion pipeline material, not only the corrosiveness but also the compatibility should be considered, and the selected material cannot promote the decomposition of hydrogen peroxide. Considering the characteristics of substances such as acids (such as carbon dioxide and hydrochloric acid as acidifying agents), alkalis (such as lime milk as a neutralizing agent), and strong oxidants (such as hydrogen peroxide) involved in the production process, 316L stainless steel, polyethylene, polypropylene, and polyvinyl chloride materials are selected as the anti-corrosion pipeline lining.

[0047] Example 2:

[0048] Refer to the appendix Figure 2, A pre - advanced oxidation treatment system for drinking water raw water, comprising a first pipeline mixer 1, a second pipeline mixer 2, a neutralization device 3, a raw material conveying device 4, a pH on - line monitor 5, and an automatic feeding system 6.

[0049] Among them, the first pipeline mixer 1, the second pipeline mixer 2, the neutralization device 3, and the raw material conveying device 4 refer to Embodiment 1.

[0050] (1) The pH on - line monitor 5 includes a pH sensor and a secondary instrument. The pH sensor is located at the rear end of the first pipeline mixer 1 and inside the neutralization device 3.

[0051] The pH sensor can adopt a differential pH sensor. The differential pH sensor is based on differential electrode measurement technology, has three electrodes, measures the pH of the system by measuring the difference values of the measuring electrode and the reference electrode relative to the differential electrode, then amplifies and outputs a standard signal, and transmits it to the secondary instrument and the lower - computer PLC cabinet 61 of the automatic feeding system 6 through a cable. At the same time, in the case where the raw water pollutes the pH electrode, the buffer solution set inside the differential pH sensor effectively improves the accuracy of the reading.

[0052] (2) The automatic feeding system 6 includes a lower - computer PLC cabinet 61, an upper - computer industrial computer 62, a first frequency converter 63, and a second frequency converter 64. The lower - computer PLC cabinet 61 is connected to the upper - computer industrial computer 62, the first frequency converter 63, the second frequency converter 64, and the pH sensor respectively through a wireless network or a cable. The first frequency converter 63 is connected to the acidifying agent conveying device 41, and the second frequency converter 64 is connected to the neutralizing agent conveying device 44.

[0053] The lower - computer PLC cabinet 61 writes the operating states of the first frequency converter 63 and the second frequency converter 64 into the memory data in real - time for the upper - computer industrial computer 62 to read. At the same time, it receives the standard signal transmitted from the pH on - line monitor 5 and transmits it to the upper - computer industrial computer 62 for simulation. After a series of algorithm processing, the upper - computer industrial computer 62 outputs a signal to the lower - computer PLC cabinet 61 through a function module, and thereby adjusts the first frequency converter 63 and the second frequency converter 64, controls the start, stop, speed, and changes the feeding amount of the acidifying agent conveying device 41 and the neutralizing agent conveying device 44, and further realizes the automatic adjustment of the system pH.

[0054] Embodiment 3:

[0055] Refer to the appendix Figure 3 , A pre - advanced oxidation treatment system for drinking water raw water, comprising a first pipeline mixer 1, a second pipeline mixer 2, a neutralization device 3, a raw material conveying device 4, a pH on - line monitor 5, an automatic feeding system 6, and an emergency feeding system 7.

[0056] Among them, the first pipeline mixer 1, the second pipeline mixer 2, the neutralization device 3, and the raw material conveying device 4 refer to Embodiment 1, and the pH on-line monitor 5 and the automatic feeding system 6 refer to Embodiment 2.

[0057] The emergency feeding system 7 includes a storage device 71 and a power-off open solenoid valve 72. The storage device 71 is located above the first pipeline mixer 1, the second pipeline mixer 2, and the neutralization device 3, and is connected to each feeding port and the power-off open solenoid valve 72 through pipelines.

[0058] The power-off open solenoid valve 72 has both power-off detection and feeding functions. When power is off, the power-off open solenoid valve 72 of the emergency feeding system 7 loses power and opens, and conveys the raw materials in the storage device 71 above the feeding port to the feeding port through the pipeline, ensuring continuous and stable feeding of the liquid material.

[0059] In summary, starting from the equipment and land costs of the Fenton reaction device, considering the feasibility of using a pipeline structure to replace the Fenton tower or Fenton tank, the present application designs a pre-advanced oxidation treatment system for drinking water raw water. The system includes a first pipeline mixer, a second pipeline mixer, a neutralization device, a raw material conveying device, a pH on-line monitor, an automatic feeding system, and an emergency feeding system. While effectively reducing the cost of the Fenton process, it can achieve automatic feeding of raw materials and is equipped with power outage emergency measures to meet the requirements of the raw water pretreatment system.

[0060] The above are only some embodiments of the present utility model. For those skilled in the art, without departing from the inventive concept of the present utility model, several modifications and improvements can still be made, and these all belong to the protection scope of the present utility model.

Claims

1. A pre - advanced oxidation treatment system for drinking water raw water, comprising a first pipeline mixer, a second pipeline mixer, a neutralization device, a raw material conveying device, and connecting pipelines connecting the above - mentioned parts. Characterized in that, The raw material conveying device includes an acidifying agent conveying device, a ferrous salt conveying device, a hydrogen peroxide conveying device, and a neutralizing agent conveying device; The first pipeline mixer is connected to the acidifying agent conveying device and the ferrous salt conveying device; The second pipeline mixer is connected to the first pipeline mixer and the hydrogen peroxide conveying device; The neutralization device is connected to the second pipeline mixer and the neutralizing agent conveying device.

2. The pre - advanced oxidation treatment system for drinking water raw water according to claim 1, Characterized in that, The acidifying agent conveying device includes a carbon dioxide feeding device, and the carbon dioxide feeding device is connected to the first pipeline mixer.

3. The pre - advanced oxidation treatment system for drinking water raw water according to claim 2, Characterized in that, The acidifying agent conveying device further includes a hydrochloric acid feeding pump, and the hydrochloric acid feeding pump is connected to the first pipeline mixer.

4. The pre - advanced oxidation treatment system for drinking water raw water according to claim 2, Characterized in that, The neutralizing agent conveying device includes a lime feeding pump, and the lime feeding pump is connected to the neutralization device.

5. The pre - advanced oxidation treatment system for drinking water raw water according to any one of claims 1 to 4, Characterized in that, It further includes a pH on - line monitor, the pH on - line monitor includes a pH sensor and a secondary instrument, and the pH sensor is connected to the secondary instrument; The pH sensor is composed of a first pH sensor arranged inside the first pipeline mixer and a second pH sensor arranged inside the neutralization device.

6. The pre - advanced oxidation treatment system for drinking water raw water according to claim 5, Characterized in that, The pH sensor is a differential pH sensor.

7. The pre - advanced oxidation treatment system for drinking water raw water according to claim 5, Characterized in that, It further includes an automatic feeding system, the automatic feeding system includes a lower - level PLC cabinet, an upper - level industrial computer, and a frequency converter; The frequency converter includes a first frequency converter connected to the acidifying agent conveying device and a second frequency converter connected to the neutralizing agent conveying device; The lower - level PLC cabinet is respectively connected to the upper - level industrial computer, the first frequency converter, the second frequency converter, and the pH sensor.

8. The pre - advanced oxidation treatment system for drinking water raw water according to any one of claims 1 to 4, Characterized in that, It further includes an emergency feeding system, the emergency feeding system includes a power - off detection device, a signal transmission device, a feeding device, and a storage device; The power - off detection device is connected to the feeding device through the signal transmission device; The feeding device is connected to the storage device, the first pipeline mixer, the second pipeline mixer, and the neutralization device.

9. The pre - advanced oxidation treatment system for drinking water raw water according to claim 8, Characterized in that, The power-off detection device, the signal transmission device, and the feeding device are specifically power-off opening type solenoid valves; The power-off opening type solenoid valves are arranged among the connecting pipelines where the storage device is respectively connected to the first pipeline mixer, the second pipeline mixer, and the neutralization device.

10. The drinking water raw water pre-advanced oxidation treatment system according to any one of claims 1 to 4, characterized in that the inner walls of the first pipeline mixer, the second pipeline mixer, and the connecting pipelines are all coated with an anti-corrosion coating and / or are provided with an anti-corrosion lining.

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