Reclaimed water reuse pretreatment system in metal processing industry

Abstract

The utility model relates to a water reuse pretreatment system in the metal processing industry, which comprises an adjusting unit, a reaction unit and an adsorption unit, the adjusting unit comprises a first reaction tank, a first stirrer is arranged in the first reaction tank, a first feed port is arranged at the top of the first reaction tank, and a first PH detector is arranged in the first reaction tank; the reaction unit comprises a second reaction tank and a third reaction tank, a second stirrer is arranged in the second reaction tank, a second feeding hole is formed in the top of the second reaction tank, and the second reaction tank is communicated with the first reaction tank; a third stirrer is arranged in the third reaction tank; the adsorption unit comprises a fourth reaction tank, a fourth stirrer is arranged in the fourth reaction tank, a third feeding hole is formed in the top of the fourth reaction tank, and a second PH detector is arranged in the fourth reaction tank. According to the utility model, the water reuse pretreatment process in the metal processing industry is optimized, and the COD (Chemical Oxygen Demand), the PH (Potential of Hydrogen) and the content of heavy metal ions in effluent are greatly reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of industrial wastewater treatment, in particular to a water reuse pretreatment system in metal processing industry. Background Art

[0002] The metal processing industry often uses acidic cleaning agents such as hydrochloric acid, sulfuric acid, oxalic acid, etc. during the metal processing process, which will make the wastewater highly acidic. The pH value of such wastewater is usually between 2-4; the metal corrosive agents, cleaning agents and metal powders produced by the previous production and use are difficult to degrade naturally in the wastewater, resulting in a high COD content; copper, zinc, aluminum, nickel, chromium and other metal components enter the wastewater in the form of ions, which has a huge impact on the environment and is difficult to eliminate and degrade by biological treatment. Therefore, the metal processing industry generally uses "physical and chemical pretreatment + biochemical treatment + membrane treatment" as the process of the reclaimed water reuse system; the requirements of the biochemical system and membrane method for the influent water quality determine that the physical and chemical pretreatment needs targeted treatment capabilities for the three characteristics of strong acidity, high COD value and high heavy metal ion content of the metal processing industry wastewater.

[0003] In the prior art, the common process used for physical and chemical pretreatment of water reuse in the metal processing industry is: "PH adjustment + coagulation (PAC addition) + flocculation (PAM addition) + sedimentation clarification". The pretreatment system has the following disadvantages: affected by the effects of coagulants and flocculants, the pH adjustment is single, and the alkali consumption is large; the removal effect of ionic heavy metal components is limited; the removal effect of high-concentration COD is limited. Utility Model Content

[0004] Therefore, the technical problem to be solved by the utility model is to overcome the defect of poor treatment effect of metal processing wastewater in the prior art.

[0005] In order to solve the above technical problems, the utility model provides a water reuse pretreatment system for the metal processing industry, comprising:

[0006] A regulating unit, wherein the regulating unit comprises a first reaction tank, a first stirrer is arranged in the first reaction tank, a first feed inlet is arranged at the top of the first reaction tank, and a first pH detector is arranged in the first reaction tank;

[0007] A reaction unit, wherein the reaction unit comprises a second reaction tank and a third reaction tank, wherein a second stirrer is arranged in the second reaction tank, a second feed inlet is arranged at the top of the second reaction tank, and the second reaction tank is connected to the first reaction tank; and a third stirrer is arranged in the third reaction tank;

[0008] The adsorption unit comprises a fourth reaction tank, a fourth stirrer is arranged in the fourth reaction tank, a third feed port is arranged at the top of the fourth reaction tank, and a second pH detector is arranged in the fourth reaction tank.

[0009] In one embodiment of the utility model, a first water inlet and a first drain are provided on the first reaction tank, a second water inlet and a second drain are provided on the second reaction tank, and a first water pump is provided between the first drain and the second water inlet.

[0010] In one embodiment of the utility model, the third reaction tank is provided with a third water inlet and a third drain outlet, the fourth reaction tank is provided with a fourth water inlet and a fourth drain outlet, a second water pump is provided between the third water inlet and the second drain outlet, and a third water pump is provided between the third drain outlet and the fourth water inlet.

[0011] In one embodiment of the utility model, a first liquid level gauge is provided in the first reaction tank, a second liquid level gauge is provided in the second reaction tank, the first liquid level gauge is electrically connected to the first mixer, and the second liquid level gauge is electrically connected to the first water pump and the second mixer.

[0012] In one embodiment of the utility model, a third liquid level gauge is provided in the third reaction tank, a fourth liquid level gauge is provided in the fourth reaction tank, the third liquid level gauge is electrically connected to the second water pump and the third mixer, and the fourth liquid level gauge is electrically connected to the third water pump and the fourth mixer.

[0013] In one embodiment of the present invention, the first water pump, the second water pump, the third water pump and the fourth water pump are all corrosion-resistant pumps.

[0014] In one embodiment of the present invention, a slope is provided at the bottom of the fourth reaction tank.

[0015] In one embodiment of the utility model, a sewage outlet is provided at the bottom of the fourth reaction tank, and a sewage valve is provided at the port of the sewage outlet.

[0016] The above technical solution of the utility model has the following advantages compared with the prior art:

[0017] The utility model discloses a water reuse pretreatment system for the metal processing industry, which uses a graded adjustment of pH, and embeds Fenton reaction, activated carbon, and heavy metal ion capture agents. The characteristics of the acidic wastewater quality of the metal processing industry are reasonably utilized, and a small amount of alkali is added to adjust the pH to the optimal range of the Fenton reaction. The Fenton reagent destroys the macromolecular organic matter into small molecular organic matter, and then the activated carbon adsorbs it. This system optimizes the water reuse pretreatment process in the metal processing industry, greatly reduces the content of effluent COD, pH, and heavy metal ions, and at the same time has the advantages of good pretreatment effect, low difficulty in connecting with subsequent processes, good environmental performance, simple operation and maintenance, and stable effluent water quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to make the content of the utility model easier to understand, the utility model is further described in detail according to the specific embodiments of the utility model in combination with the accompanying drawings, wherein

[0019] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0020] Figure 2 for Figure 1 The structural diagram of the middle regulating unit;

[0021] Figure 3 for Figure 1 Schematic diagram of the structure of the reaction unit;

[0022] Figure 4 for Figure 1 Schematic diagram of the structure of the adsorption unit;

[0023] Description of the accompanying drawings: 1. regulating unit; 2. reaction unit; 3. adsorption unit; 11. first reaction tank; 12. first mixer; 13. first pH detector; 14. first liquid level gauge; 15. first water pump; 21. second reaction tank; 21. second reaction tank; 22. third reaction tank; 23. second mixer; 24. third mixer; 25. second liquid level gauge; 26. third liquid level gauge; 27. second water pump; 28. third water pump; 31. fourth reaction tank pool; 32, the fourth mixer; 33, the second pH detector; 34, the fourth liquid level gauge; 35, the sewage valve; 111, the first water inlet; 112, the first drainage outlet; 113, the first feed inlet; 211, the second water inlet; 212, the second drainage outlet; 213, the second feed inlet; 221, the third water inlet; 222, the third drainage outlet; 311, the fourth water inlet; 312, the fourth drainage outlet; 313, the third feed inlet; 314, the sewage outlet; 315, the inclined plane. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0025] Reference Figure 1-Figure 4 As shown, the utility model discloses a water reuse pretreatment system for the metal processing industry, comprising:

[0026] The regulating unit 1 comprises a first reaction tank 11, a first stirrer 12 is arranged in the first reaction tank 11, a first feed inlet 113 is arranged at the top of the first reaction tank 11, and a first pH detector 13 is arranged in the first reaction tank 11;

[0027] The reaction unit 2 includes a second reaction tank 21 and a third reaction tank 22. The second reaction tank 21 is provided with a second stirrer 23. The top of the second reaction tank 21 is provided with a second feed inlet 213. The second reaction tank 21 is connected to the first reaction tank 11. The third reaction tank 22 is provided with a third stirrer 24.

[0028] The adsorption unit 3 comprises a fourth reaction tank 31 , a fourth stirrer 32 is arranged in the fourth reaction tank 31 , a third feed port 313 is arranged at the top of the fourth reaction tank 31 , and a second pH detector 33 is arranged in the fourth reaction tank 31 .

[0029] It is conceivable that the metal processing industry uses acidic cleaning agents such as hydrochloric acid, sulfuric acid, oxalic acid, etc. during the metal processing process, which will make the wastewater highly acidic. The pH value of such wastewater is usually between 2-4. The above-mentioned regulating unit 1 is used to adjust the pH of the wastewater first. Specifically, the wastewater is first pumped into the first reaction tank 11, and then the alkali solution (whose main component is NaOH) is neutralized by adding alkali. It should be noted that in order to ensure the adequacy of the mixing of the alkali solution and the wastewater, stirring is performed while adding the alkali solution to avoid adding too much alkali solution, which affects the subsequent treatment. The first PH detector 13 is used to detect the pH value in the first reaction tank 11, adjust the pH of the water in the first reaction tank 11 to between 3 and 4, then stop adding the alkali solution, start adding ferrous sulfate, and prepare for the reaction of the reaction unit 2. When adding ferrous sulfate, it is necessary to ensure that the first mixer 12 continues to work to fully fuse the ferrous sulfate.

[0030] The reaction carried out in the reaction unit 2 is mainly a Fenton reaction, that is, hydrogen peroxide is added to the second feed port 213, and the second mixer 23 is stirred at the same time, so that the hydrogen peroxide is fully fused, that is, in an acidic environment, the hydrogen peroxide reacts with ferrous ions to generate hydroxyl radicals. After entering the third reaction tank 22, the third mixer 24 continues to operate to fully mix the wastewater and the reagent for oxidation reaction to remove a large amount of COD.

[0031] After entering the fourth reaction tank 31 of the adsorption unit 3, alkali solution is added from the fourth feed port to adjust the pH of the wastewater to 7-8 to make it alkaline, and then activated carbon and heavy metal ion capture agent are added to effectively adsorb and remove small molecular organic matter remaining in the Fenton reaction.

[0032] The utility model adopts the method of adjusting pH in stages, and embedding Fenton reaction, activated carbon and heavy metal ion capture agent. The characteristics of acidic wastewater quality in metal processing industry are reasonably utilized, and a small amount of alkali is added to adjust pH to the optimal range of Fenton reaction. Fenton reagent destroys macromolecular organic matter into small molecular organic matter, and then activated carbon adsorbs. This system optimizes the pretreatment process of water reuse in metal processing industry, greatly reduces the content of COD, pH and heavy metal ions in effluent, and at the same time has the advantages of good pretreatment effect, low difficulty in connecting with subsequent processes, good environmental performance, simple operation and maintenance, and stable effluent water quality.

[0033] Furthermore, the first reaction tank 11 is provided with a first water inlet 111 and a first drain outlet 112, the second reaction tank 21 is provided with a second water inlet 211 and a second drain outlet 212, and a first water pump 15 is provided between the first drain outlet 112 and the second water inlet 211; the third reaction tank 22 is provided with a third water inlet 221 and a third drain outlet 222, the fourth reaction tank 31 is provided with a fourth water inlet 311 and a fourth drain outlet 312, a second water pump 27 is provided between the third water inlet 221 and the second drain outlet 212, and a third water pump 28 is provided between the third drain outlet 222 and the fourth water inlet 311.

[0034] Specifically, in the utility model, water is pumped between the first reaction tank 11 and the second reaction tank 21 by the first water pump 15, the second water pump 27 is used to pump the water in the second reaction tank 21 into the third reaction tank 22, and the third water pump 28 is used to pump the water in the third reaction tank 22 into the fourth reaction tank 31. It should be noted that, since some precipitation will be produced in the fourth reaction tank 31 during the adsorption process, the fourth drain port 312 is set at one end of the side wall near the top. As a preferred embodiment of the utility model, the first water pump 15, the second water pump 27, the third water pump 28 and the fourth water pump are all corrosion-resistant pumps to avoid corrosion during use; similarly, the pipelines in the transportation process also use polytetrafluoroethylene pipes to avoid corrosion of the pipelines during transportation.

[0035] In one embodiment of the utility model, a first liquid level gauge 14 is provided in the first reaction tank 11, a second liquid level gauge 25 is provided in the second reaction tank 21, the first liquid level gauge 14 is electrically connected to the first mixer 12, and the second liquid level gauge 25 is electrically connected to the first water pump 15 and the second mixer 23. A third liquid level gauge 26 is provided in the third reaction tank 22, a fourth liquid level gauge 34 is provided in the fourth reaction tank 31, the third liquid level gauge 26 is electrically connected to the second water pump 27 and the third mixer 24, and the fourth liquid level gauge 34 is electrically connected to the third water pump 28 and the fourth mixer 32.

[0036] Specifically, the first liquid level meter 14 detects the liquid level in the first reaction tank 11. When it reaches the set value, a feedback signal is sent to the first agitator 12, and the first agitator 12 starts to work. After the second liquid level meter 25 detects the liquid level height signal of the second reaction tank 21, a feedback signal is sent to the first water pump 15 and the second agitator 23, and the first water pump 15 stops working and the second agitator 23 starts working. Similarly, the third liquid level meter 26 and the fourth liquid level meter 34 are used to control the start and stop of the water pump and the operation of the agitator.

[0037] Furthermore, a slope 315 is provided at the bottom of the fourth reaction tank 31. Specifically, during adsorption in the fourth reaction tank 31, some precipitation will be generated, and the rate of precipitation can be increased by the slope 315 at the bottom of the fourth reaction tank 31. The impurity content in the wastewater entering the subsequent process is ensured, and the maintenance cycle is extended.

[0038] Furthermore, a drain port 314 is provided at the bottom of the fourth reaction tank 31, and a drain valve 35 is provided at the port of the drain port 314. Specifically, the sediment at the bottom can be discharged from the drain port 314 at the bottom of the fourth reaction tank 31, and after a period of treatment, the sediment accumulated at the bottom can be discharged by opening the drain valve 35.

[0039] The utility model introduces a pretreatment system for reuse of reclaimed water in the metal processing industry, which uses a graded adjustment of pH and embeds Fenton reaction, activated carbon, and heavy metal ion capture agents. The characteristics of the acidic wastewater quality of the metal processing industry are reasonably utilized, and a small amount of alkali is added to adjust the pH to the optimal range of the Fenton reaction. The Fenton reagent destroys large molecular organic matter and turns it into small molecular organic matter, which is then adsorbed by activated carbon. This system optimizes the pretreatment process for reuse of reclaimed water in the metal processing industry, greatly reduces the content of COD, pH, and heavy metal ions in the effluent, and at the same time has the advantages of good pretreatment effect, low difficulty in connecting with subsequent processes, good environmental performance, simple operation and maintenance, and stable effluent water quality.

[0040] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention of the utility model.

Claims

1. A water reuse pretreatment system for metal processing industry, characterized in that: include: A regulating unit, wherein the regulating unit comprises a first reaction tank, a first stirrer is arranged in the first reaction tank, a first feed inlet is arranged at the top of the first reaction tank, and a first pH detector is arranged in the first reaction tank; A reaction unit, wherein the reaction unit comprises a second reaction tank and a third reaction tank, wherein the second reaction tank is connected to the third reaction tank, a second stirrer is arranged in the second reaction tank, a second feed inlet is arranged at the top of the second reaction tank, the second reaction tank is connected to the first reaction tank; and a third stirrer is arranged in the third reaction tank; The adsorption unit comprises a fourth reaction tank, a fourth stirrer is arranged in the fourth reaction tank, a third feed port is arranged at the top of the fourth reaction tank, and a second pH detector is arranged in the fourth reaction tank.

2. The water reuse pretreatment system for the metal processing industry according to claim 1 is characterized by: The first reaction tank is provided with a first water inlet and a first drain outlet, the second reaction tank is provided with a second water inlet and a second drain outlet, and a first water pump is provided between the first drain outlet and the second water inlet.

3. The water reuse pretreatment system for the metal processing industry according to claim 2 is characterized by: The third reaction tank is provided with a third water inlet and a third drain outlet, the fourth reaction tank is provided with a fourth water inlet and a fourth drain outlet, a second water pump is provided between the third water inlet and the second drain outlet, and a third water pump is provided between the third drain outlet and the fourth water inlet.

4. The water reuse pretreatment system for the metal processing industry according to claim 2 is characterized by: A first liquid level gauge is provided in the first reaction tank, and a second liquid level gauge is provided in the second reaction tank. The first liquid level gauge is electrically connected to the first stirrer, and the second liquid level gauge is electrically connected to the first water pump and the second stirrer.

5. The water reuse pretreatment system for the metal processing industry according to claim 3 is characterized by: A third liquid level gauge is provided in the third reaction tank, a fourth liquid level gauge is provided in the fourth reaction tank, the third liquid level gauge is electrically connected to the second water pump and the third agitator, and the fourth liquid level gauge is electrically connected to the third water pump and the fourth agitator.

6. The water reuse pretreatment system for the metal processing industry according to claim 3 is characterized by: The first water pump, the second water pump, the third water pump and the fourth water pump are all corrosion-resistant pumps.

7. The water reuse pretreatment system for the metal processing industry according to claim 1 is characterized by: The bottom of the fourth reaction tank is provided with an inclined surface.

8. The water reuse pretreatment system for the metal processing industry according to claim 1 is characterized by: A sewage outlet is arranged at the bottom of the fourth reaction tank, and a sewage valve is arranged at the port of the sewage outlet.

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