Industrial chromium-containing wastewater treatment device

Abstract

The utility model discloses an industrial chromium-containing wastewater treatment device which comprises a reduction reaction tank, the right end of the reduction reaction tank is connected with the neutralization reaction tank, the right end of the neutralization reaction tank is connected with the coagulation reaction tank, and the right end of the coagulation reaction tank is connected with the inclined tube sedimentation tank. The method comprises the following steps: adding sodium hydroxide into trivalent chromium ions to generate indissolvable chromic hydroxide, firstly adding a polyacrylamide flocculant to generate relatively large muddy alum, then adding polyaluminum chloride to settle, settling in an inclined tube settling zone in an inclined tube settling tank, enabling settled sewage to enter a clean water tank, and when the chromium content detected by an online heavy metal monitor is lower than 0.5 mg / L, discharging the sewage from the clean water tank. The industrial wastewater meeting the standard is discharged, and the device is compact in structure, small in occupied area, convenient to operate, high in treatment efficiency, low in treatment cost and easy to popularize.

Description

Technical Field

[0001] The utility model relates to the field of chromium-containing wastewater treatment, in particular to an industrial chromium-containing wastewater treatment device. Background Art

[0002] Chromium is a commonly used metal widely used in electroplating, semiconductor, PC circuit board and other industries. There are two common valence states: trivalent and hexavalent. Hexavalent chromium is highly toxic, while trivalent chromium is slightly toxic. Therefore, the treatment of hexavalent chromium is generally to reduce hexavalent chromium to trivalent chromium with a reducing agent before treatment.

[0003] At present, there are many kinds of industrial wastewater treatment devices used in metallurgy, chemical industry, electroplating, leather, printing and dyeing and other industries. Ion exchange treatment devices require large one-time investment and are complex to operate. Electrolysis equipment has complex processes and high energy consumption.

[0004] One-step chromium removal devices, intermittent chromium-containing wastewater treatment devices and other equipment can only treat chromium-containing industrial wastewater with a chromium concentration of less than 50 g / L, and cannot treat large-flow, high-concentration chromium-containing industrial wastewater. In addition, traditional equipment is manually operated, inconvenient to manage, and has low treatment efficiency. Therefore, existing chromium-containing industrial wastewater treatment devices are limited to a certain extent and cannot meet the requirements of controlling industrial wastewater pollution and rationally utilizing and protecting water resources. Utility Model Content

[0005] The utility model aims to provide an industrial chromium-containing wastewater treatment device to solve the above-mentioned technical problem of efficiently treating chromium-containing industrial wastewater of various concentrations and different flow rates.

[0006] In order to solve the above technical problems, the utility model provides an industrial chromium-containing wastewater treatment device, which includes a reduction reaction tank; the right end of the reduction reaction tank is connected to the neutralization reaction tank, the right end of the neutralization reaction tank is connected to the coagulation reaction tank, the right end of the coagulation reaction tank is connected to the inclined tube sedimentation tank, the right end of the inclined tube sedimentation tank is connected to the clear water tank, a microcomputer automatic control box is arranged on the side of the clear water tank, the middle parts of the reduction reaction tank, the neutralization reaction tank and the coagulation reaction tank are respectively penetrated with mixing and stirring devices, the upper left end of the reduction reaction tank is penetrated with an acidic agent dosing barrel and a reducing agent dosing barrel, the upper left end of the neutralization reaction tank is penetrated with an alkaline agent dosing barrel, and the upper left end of the coagulation reaction tank is penetrated with a coagulant dosing barrel and a flocculant dosing barrel.

[0007] Furthermore, the mixing and stirring device includes a driving motor and an output shaft, and a baffle is longitudinally arranged in the middle of the upper end of the reduction reaction tank, the neutralization reaction tank and the coagulation reaction tank, and a through hole is arranged on the baffle, and the inner diameter of the through hole is loosely matched with the outer diameter of the output shaft, the output shaft passes through the through hole, and the lower end of the output shaft is connected to the stirring plate.

[0008] Furthermore, a water inlet pipe is connected to the upper right end of the reduction reaction tank, a first water weir is provided at the upper right end of the reduction reaction tank, a first pH meter is provided in the first water weir, and a second water weir is provided at the upper right end of the neutralization reaction tank, a second pH meter is provided in the water weir.

[0009] Furthermore, a dosing valve is arranged between the reducing agent dosing barrel and the reduction reaction tank, a dosing valve is arranged between the acidic agent dosing barrel and the reduction reaction tank, a dosing valve is arranged between the alkaline agent dosing barrel and the neutralization reaction tank, a dosing valve is arranged between the coagulant dosing barrel and the coagulation reaction tank, and a dosing valve is arranged between the flocculant dosing barrel and the coagulation reaction tank.

[0010] Furthermore, the lower left portion of the inclined tube sedimentation tank is connected to the coagulation reaction tank, a mud discharge pipe is arranged below the inclined tube sedimentation tank, and an inclined tube sedimentation area is arranged above the inclined tube sedimentation tank.

[0011] Furthermore, a water pump is provided at the bottom of the clear water tank, a drain pipe is provided at one end of the water pump, a three-way valve is provided at one end of the drain pipe, one end of the three-way valve is connected to the water inlet pipe, and the other end of the three-way valve is connected to the main pipeline.

[0012] Furthermore, an online heavy metal monitor and a liquid level detector are arranged in the microcomputer automatic control box.

[0013] The beneficial effects of the utility model are as follows: compared with the prior art, the chromium-containing wastewater treatment device for industrial chromium-containing wastewater enters the reduction reaction tank through the water inlet pipe, the pH of the chromium-containing wastewater is reduced to about 2.5 by the sulfuric acid in the acidic agent adding barrel on the reduction reaction tank, the hexavalent chromium ions in the water are reduced to trivalent chromium ions by the reducing agent sodium sulfite in the reducing agent adding barrel, the trivalent chromium ions are generated into insoluble chromium hydroxide by the sodium hydroxide in the alkaline agent adding barrel on the neutralization reaction tank, and then to the coagulation reaction tank, polyacrylamide flocculant is added to generate larger mud alum, and then polyaluminium chloride is added for sedimentation, and then the industrial wastewater enters the inclined The inclined tube sedimentation area in the tube sedimentation tank is used for sedimentation, and the settled sludge will be discharged through the sludge discharge pipe. The sewage after sedimentation enters the clear water tank. The clear water tank will use the online heavy metal monitor to detect that the chromium content is lower than 0.5.mg / L. The three-way valve will close the water inlet pipe, connect the main pipeline and the drain pipe, and discharge the industrial wastewater that meets the standards. If the online heavy metal monitor detects that the chromium content exceeds the standard, the three-way valve will close the main pipeline, connect the water inlet pipe and the drain pipe, and the industrial wastewater that does not meet the standards will enter the reduction reaction tank again. The device has a compact structure, small footprint, easy operation, high treatment efficiency, low treatment cost, and is easy to promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1It is a schematic diagram of the transverse cross-sectional structure of an industrial chromium-containing wastewater treatment device.

[0015] Figure 2 It is a first stereoscopic structural schematic diagram of an industrial chromium-containing wastewater treatment device.

[0016] Figure 3 This is a second stereoscopic structural schematic diagram of an industrial chromium-containing wastewater treatment device.

[0017] Figure 4 It is a schematic diagram of the vertical cross-sectional structure of an industrial chromium-containing wastewater treatment device.

[0018] Among them: 1. reduction reaction tank; 2. neutralization reaction tank; 3. coagulation reaction tank; 4. inclined tube sedimentation tank; 5. clear water tank; 6. mixing and stirring device; 9. reducing agent dosing barrel; 10. dosing valve; 11. alkaline agent dosing barrel; 13. acidic agent dosing barrel; 15. coagulant dosing barrel; 17. flocculant dosing barrel; 19. water pump; 191. drainage pipe; 20. three-way valve; 21. microcomputer automatic control box; 22. online heavy metal monitor; 23. liquid level detector; 24. first pH meter; 25. second pH meter; 26. mud discharge pipe; 27. baffle; 271. through hole; 28. water inlet pipe; 29. ​​driving motor; 30. stirring plate; 31. output shaft; 32. main pipeline; 33. first water weir trough; 34. second water weir trough; 35. third water weir trough; 36. inclined tube sedimentation area. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiment is only one embodiment of the utility model, not all embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the utility model.

[0020] In order to make the objectives, technical solutions and advantages of the present application more clear, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0021] In the following description, references to "one embodiment", "an embodiment", "an example", "an example", etc. indicate that the embodiment or example described in this way may include specific features, structures, characteristics, properties, elements or limitations, but not every embodiment or example necessarily includes the specific features, structures, characteristics, properties, elements or limitations. In addition, repeated use of the phrase "according to one embodiment of the present application" may refer to the same embodiment, but does not necessarily refer to the same embodiment.

[0022] like Figure 1As shown, it includes a reduction reaction tank 1; the right end of the reduction reaction tank 1 is connected to the neutralization reaction tank 2, the right end of the neutralization reaction tank 2 is connected to the coagulation reaction tank 3, the right end of the coagulation reaction tank 3 is connected to the inclined tube sedimentation tank 4, the right end of the inclined tube sedimentation tank 4 is connected to the clear water tank 5, and a microcomputer automatic control box 21 is arranged on the side of the clear water tank 5, and a mixing and stirring device 6 is respectively penetrated through the middle of the reduction reaction tank 1, the neutralization reaction tank 2 and the coagulation reaction tank 3, and a reducing agent dosing barrel 9 and an acidic agent dosing barrel 13 are penetrated at the upper left end of the reduction reaction tank 1, the acidic agent is sulfuric acid, and the reducing agent is sodium sulfite, the upper left end of the neutralization reaction tank 2 is penetrated by an alkaline agent dosing barrel 11, and the alkaline agent is sodium hydroxide, and the upper left end of the coagulation reaction tank 3 is penetrated by a coagulant dosing barrel 15 and a flocculant dosing barrel 17, the flocculant is polyacrylamide flocculant, and the coagulant is polyaluminum chloride.

[0023] The chromium-containing wastewater enters the reduction reaction tank 1 through the water inlet pipe 28, and the pH of the chromium-containing wastewater is reduced to about 2.5 by the sulfuric acid in the acidic agent dosing barrel 13 on the reduction reaction tank 1, and then the hexavalent chromium ions in the water are reduced to trivalent chromium ions by the reducing agent sodium sulfite in the reducing agent dosing barrel 9, and the pH value change in the reduction reaction tank 1 is detected by the first pH meter 24, and then the wastewater containing trivalent chromium ions in the reduction reaction tank 1 enters the neutralization reaction tank 2 through the first water weir trough 33, and the trivalent chromium ions are converted into insoluble chromium hydroxide by the sodium hydroxide in the alkaline agent dosing barrel 11 on the neutralization reaction tank 2, and the pH value change in the neutralization reaction tank 2 is detected by the second pH meter 25, and then the wastewater containing chromium hydroxide in the neutralization reaction tank 2 enters the coagulation reaction tank 3 through the second water weir trough 34, and the flocculant dosing barrel on the coagulation reaction tank 3 is first added. The polyacrylamide flocculant in 17 generates a larger sludge alum, which is then added to the polyaluminium chloride in the coagulant dosing barrel 15 on the coagulation reaction tank 3 for sedimentation. After that, the industrial wastewater enters the inclined tube sedimentation area 36 in the inclined tube sedimentation tank 4 for sedimentation. The settled sludge will be discharged through the mud discharge pipe 26, and the sewage after sedimentation will enter the clear water tank 5 through the third water weir trough 35. The clear water tank 5 will detect that the chromium content is lower than 0.5 mg / L through the online heavy metal monitor 22. The three-way valve 20 closes the water inlet pipe 28, connects the main pipeline 32 and the drain pipe 191, and discharges the industrial wastewater that meets the standards. If the online heavy metal monitor 22 detects that the chromium content exceeds the standard, the three-way valve 20 closes the main pipeline 32, connects the water inlet pipe 28 and the drain pipe 191, and the industrial wastewater that does not meet the standards will enter the reduction reaction tank 1 again.

[0024] The mixing and stirring device 6 includes a driving motor 29 and an output shaft 31. The driving motor 29 is of model Y180M-2. This is the prior art and will not be elaborated on. A baffle 27 is longitudinally arranged in the middle of the upper end of the reduction reaction tank 1, the neutralization reaction tank 2 and the coagulation reaction tank 3. A through hole 271 is arranged on the baffle 27. The inner diameter of the through hole 271 is clearance-matched with the outer diameter of the output shaft 31. The output shaft 31 passes through the through hole 271. The lower end of the output shaft 31 is connected to the stirring plate 30. Through the setting of the baffle 27, the dosing barrel is located on the left side, which can promote the mixing of the reagent and the chromium-containing wastewater and improve the reaction efficiency.

[0025] A water inlet pipe 28 is connected to the upper right end of the reduction reaction tank 1, a first water weir trough 33 is arranged at the upper right end of the reduction reaction tank 1, a first pH meter 24 is arranged in the first water weir trough 33, a second water weir trough 34 is arranged at the upper right end of the neutralization reaction tank 2, a second pH meter 25 is arranged in the water weir trough, the model of the first pH meter 24 and the second pH meter 25 is SIN-PH-6001, which is the prior art and will not be elaborated in detail.

[0026] A dosing valve 10 is arranged between the reducing agent dosing barrel 9 and the reduction reaction tank 1, a dosing valve 10 is arranged between the alkaline agent dosing barrel 11 and the neutralization reaction tank 2, a dosing valve 10 is arranged between the acidic agent dosing barrel 13 and the reduction reaction tank 1, a dosing valve 10 is arranged between the coagulant dosing barrel 15 and the coagulation reaction tank 3, and a dosing valve 10 is arranged between the flocculant dosing barrel 17 and the coagulation reaction tank 3. The dosing valve 10 model is MTX-23, which is the prior art and will not be elaborated on. By setting the dosing valve 10, the dosage of the agent can be accurately controlled, thereby reducing the chromium removal cost and improving the chromium removal effect.

[0027] The lower left side of the inclined tube sedimentation tank 4 is connected to the coagulation reaction tank 3. A sludge discharge pipe 26 is arranged below the inclined tube sedimentation tank 4. An inclined tube sedimentation area 36 is arranged above the inclined tube sedimentation tank 4. The re-agglomeration of flocculent particles in the inclined tube filler in the inclined tube sedimentation tank 4 promotes further growth of particles and improves sedimentation efficiency.

[0028] A water pump 19 is provided at the bottom of the clear water tank 5 , a drain pipe 191 is provided at one end of the water pump 19 , a three-way valve 20 is provided at one end of the drain pipe 191 , one end of the three-way valve 20 is connected to the water inlet pipe 28 , and the other end of the three-way valve 20 is connected to the main pipeline 32 .

[0029] An online heavy metal monitor 22 and a liquid level detector 23 are arranged in the microcomputer automatic control box 21. The heavy metal monitor is of model ZXcm-500-Cr6, which is the prior art and will not be described in detail. The liquid level detector 23 is of model MP-C.

[0030] Working process: the chromium-containing wastewater enters the reduction reaction tank 1 through the water inlet pipe 28, the pH of the chromium-containing wastewater is adjusted to about 2.5 by the sulfuric acid in the acidic agent dosing barrel 13 on the reduction reaction tank 1, the hexavalent chromium ions in the water are reduced to trivalent chromium ions by the reducing agent sodium sulfite in the reducing agent dosing barrel 9, the wastewater containing trivalent chromium ions in the reduction reaction tank 1 enters the neutralization reaction tank 2 through the first water weir trough 33, the trivalent chromium ions are converted into insoluble chromium hydroxide by the sodium hydroxide in the alkaline agent dosing barrel 11 on the neutralization reaction tank 2, the chromium hydroxide wastewater in the neutralization reaction tank 2 enters the coagulation reaction tank 3 through the second water weir trough 34, the polyacrylamide flocculant in the flocculant dosing barrel 17 on the coagulation reaction tank 3 is first added to generate a larger sludge alum, and then Then, the polyaluminium chloride in the coagulant dosing barrel 15 on the coagulation reaction tank 3 is added for sedimentation, and then the industrial wastewater enters the inclined tube sedimentation area 36 in the inclined tube sedimentation tank 4 for sedimentation. The settled sludge will be discharged through the sludge discharge pipe 26, and the sewage after sedimentation will enter the clear water tank 5 through the third water weir trough 35. The clear water tank 5 will detect that the chromium content is lower than 0.5 mg / L through the online heavy metal monitor 22. The three-way valve 20 closes the water inlet pipe 28, connects the main pipeline and the drain pipe 191, and discharges the industrial wastewater that meets the standards. If the online heavy metal monitor 22 detects that the chromium content exceeds the standard, the three-way valve 20 closes the main pipeline, connects the water inlet pipe 28 and the drain pipe 191, and the industrial wastewater that does not meet the standards will enter the reduction reaction tank 1 again.

[0031] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An industrial chromium-containing wastewater treatment device, characterized in that: It includes a reduction reaction tank; the right end of the reduction reaction tank is connected to the neutralization reaction tank, the right end of the neutralization reaction tank is connected to the coagulation reaction tank, the right end of the coagulation reaction tank is connected to the inclined tube sedimentation tank, the right end of the inclined tube sedimentation tank is connected to the clear water tank, a microcomputer automatic control box is arranged on the side of the clear water tank, the middle parts of the reduction reaction tank, the neutralization reaction tank and the coagulation reaction tank are respectively penetrated with mixing and stirring devices, the upper left end of the reduction reaction tank is penetrated with an acidic agent dosing barrel and a reducing agent dosing barrel, the upper left end of the neutralization reaction tank is penetrated with an alkaline agent dosing barrel, and the upper left end of the coagulation reaction tank is penetrated with a coagulant dosing barrel and a flocculant dosing barrel.

2. The industrial chromium-containing wastewater treatment device according to claim 1, characterized in that: The mixing and stirring device includes a driving motor and an output shaft. A baffle is longitudinally arranged in the middle of the upper end of the reduction reaction tank, the neutralization reaction tank and the coagulation reaction tank. A through hole is arranged on the baffle. The inner diameter of the through hole is loosely matched with the outer diameter of the output shaft. The output shaft passes through the through hole, and the lower end of the output shaft is connected to the stirring plate.

3. The industrial chromium-containing wastewater treatment device according to claim 1, characterized in that: A water inlet pipe is connected to the upper right end of the reduction reaction tank, a first water weir is arranged at the upper right end of the reduction reaction tank, a first pH meter is arranged in the first water weir, a second water weir is arranged at the upper right end of the neutralization reaction tank, a second pH meter is arranged in the water weir.

4. The industrial chromium-containing wastewater treatment device according to claim 1, characterized in that: A dosing valve is arranged between the reducing agent dosing barrel and the reduction reaction tank, a dosing valve is arranged between the acidic agent dosing barrel and the reduction reaction tank, a dosing valve is arranged between the alkaline agent dosing barrel and the neutralization reaction tank, a dosing valve is arranged between the coagulant dosing barrel and the coagulation reaction tank, and a dosing valve is arranged between the flocculant dosing barrel and the coagulation reaction tank.

5. The industrial chromium-containing wastewater treatment device according to claim 1, characterized in that: The lower left side of the inclined tube sedimentation tank is connected to the coagulation reaction tank, a mud discharge pipe is arranged below the inclined tube sedimentation tank, and an inclined tube sedimentation area is arranged above the inclined tube sedimentation tank.

6. The industrial chromium-containing wastewater treatment device according to claim 3, characterized in that: A water pump is arranged at the bottom of the clear water tank, a drainage pipe is arranged at one end of the water pump, a three-way valve is arranged at one end of the drainage pipe, one end of the three-way valve is connected to the water inlet pipe, and the other end of the three-way valve is connected to the main pipeline.

7. The industrial chromium-containing wastewater treatment device according to claim 1, characterized in that: An online heavy metal monitor and a liquid level detector are arranged in the microcomputer automatic control box.

Images