High-concentration wastewater treatment system

Abstract

The utility model belongs to the technical field of wastewater treatment, and discloses a high-concentration wastewater treatment system which comprises a wastewater treatment system, a biogas treatment system and a tail gas treatment system, each wastewater treatment unit of the wastewater treatment system is provided with a pool top gas-collecting hood, and the pool top gas-collecting hoods are connected with the tail gas treatment system through pipelines; the UASB reaction tank of the wastewater treatment system is connected with the biogas treatment system through a pipeline; spray liquid outlets of the tail gas alkali spray tower of the tail gas treatment system and the biogas desulfurization tower of the biogas treatment system are connected with the aerobic O tank through pipelines. Spraying absorption liquid of the tail gas alkali spraying tower and the biogas desulfurization tower is conveyed into the aerobic O tank, so that sulfur-containing substances are oxidized in an aerobic environment of the aerobic O tank, and finally sulfur elements are discharged out of the system in a sulfate form, so that the sulfur elements cannot be accumulated in the wastewater treatment system, and the wastewater treatment efficiency is improved. The treatment effects of the biogas desulfurization tower and the tail gas alkali spray tower are improved, and hydrogen sulfide in the waste gas can be discharged up to the standard all the time.

Description

Technical Field

[0001] This utility model belongs to the field of wastewater treatment technology, and in particular relates to a high-concentration wastewater treatment system. Background Technology

[0002] High-concentration wastewater generated by production facilities mainly refers to wastewater containing epoxy chains, cyclic hydrocarbons, and benzene ring-containing substances. It has a high organic content and poor biodegradability, making direct biological treatment difficult. Therefore, Fenton reaction pretreatment is necessary to decompose the recalcitrant substances into smaller, more biodegradable molecules, improving the wastewater's biodegradability. However, current high-concentration wastewater treatment systems generate hydrogen sulfide, which, after being absorbed by alkaline scrubbing, returns to the system. This cyclical operation leads to an accumulation of hydrogen sulfide, diminishing the effectiveness of alkaline scrubbing and eventually exceeding the capacity of existing scrubbing facilities, resulting in excessive hydrogen sulfide levels in the exhaust gas. Therefore, a high-concentration wastewater treatment system that can meet environmental emission standards for hydrogen sulfide and reduce sulfur accumulation within the wastewater treatment system is needed. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model provides a high-concentration wastewater treatment system. The technical solution adopted by this utility model is as follows:

[0004] A high-concentration wastewater treatment system includes a wastewater treatment system, a biogas treatment system, and a tail gas treatment system;

[0005] The wastewater treatment system includes wastewater treatment units connected sequentially by wastewater pipelines. These wastewater treatment units are, in sequence, a high-concentration wastewater collection tank, a Fenton reaction tank, a coagulation sedimentation tank, a hydrolysis acidification tank, a hydrolysis sedimentation tank, a water distribution tank, a UASB reaction tank, an anaerobic A tank, an aerobic O tank, a secondary sedimentation tank, and an effluent tank. Each wastewater treatment unit is equipped with a top-mounted gas collection hood, which is connected to the tail gas treatment system via pipelines. The UASB reaction tank is connected to the biogas treatment system via pipelines.

[0006] The exhaust gas treatment system includes an exhaust gas alkaline spray tower, a biological deodorization tower, a dehydration tank, an activated carbon adsorption box, an induced draft fan, and an exhaust stack, all connected in sequence by gas pipelines; the biogas treatment system includes a water seal tank, a biogas desulfurization tower, and a flare device, all connected in sequence by gas pipelines; the spray liquid outlets of the exhaust gas alkaline spray tower and the biogas desulfurization tower are connected to the aerobic O2 pool via pipelines.

[0007] The technical effects achieved by employing the aforementioned technical features are as follows:

[0008] This utility model's high-concentration wastewater treatment system continuously introduces concentrated sulfuric acid and ferrous sulfate, containing large amounts of sulfates, into the Fenton reactor to decompose and flocculate the recalcitrant substances in the high-concentration wastewater. Under the action of sulfate-containing bacteria in the hydrolysis acidification tank and the UASB anaerobic tank, the hydrogen sulfide waste gas generated from sulfate decomposition and reduction is treated by the tail gas collection system. Hydrogen sulfide directly collected from the aqueous phase of the UASB anaerobic tank, along with the biogas produced by anaerobic fermentation of the wastewater, enters the biogas treatment system for further treatment. The biogas desulfurization tower and the tail gas alkaline spray tower utilize… Using alkaline solution as the absorbent, hydrogen sulfide in the waste gas is removed through an acid-base neutralization reaction mechanism and countercurrent contact between the alkaline solution and the waste gas. The alkaline solution absorbs the hydrogen sulfide to form a saturated spray absorbent, which is then transported to the aerobic O2 tank. In the aerobic environment of the aerobic O2 tank, sulfur-containing substances are oxidized, and the sulfur element is ultimately discharged from the system in the form of sulfate. Therefore, sulfur element will not accumulate in the wastewater treatment system and will not exceed the capacity of the biogas desulfurization tower and the tail gas alkaline spray tower, thus improving the treatment effect of the biogas desulfurization tower and the tail gas alkaline spray tower. The hydrogen sulfide in the waste gas can always meet the emission standards.

[0009] Furthermore, the bottom of the high-concentration wastewater collection tank is equipped with perforated aeration pipes.

[0010] The perforated aeration pipe mixes and homogenizes the high-concentration wastewater in the high-concentration wastewater collection tank.

[0011] Furthermore, the high-concentration wastewater treatment system includes multiple Fenton reaction tanks.

[0012] Furthermore, the high-concentration wastewater treatment system includes a Fenton reaction tank 1, a Fenton reaction tank 2, a Fenton reaction tank 3, and a Fenton reaction tank 4.

[0013] Concentrated sulfuric acid is added to the Fenton reaction tank to adjust the pH to 3-4, and ferrous sulfate is added as a catalyst for generating ·OH free radicals. After the wastewater enters the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank, hydrogen peroxide is added, and ·OH free radicals are generated under the catalysis of ferrous sulfate, which decomposes the recalcitrant substances in the high-concentration water. After the wastewater enters the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank, NaOH solution is added to adjust the pH to 7-8. The generated Fe(OH)3 colloid has flocculation and adsorption functions and can also remove some organic matter in the water. After the wastewater enters the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank from the Fenton reaction tank, polyaluminum chloride (PAC) and polyacrylamide (PAM) are added to further flocculate the suspended colloidal flocs in the wastewater into large particles, which are easier to separate from the wastewater.

[0014] Furthermore, each of the Fenton reaction tanks (first, second, third, and fourth) is equipped with a metering pump. The metering pumps are used for adding the reagents.

[0015] Furthermore, an equalization tank is provided between the coagulation sedimentation tank and the hydrolysis acidification tank, and the equalization tank is connected to a low-concentration wastewater collection tank.

[0016] After the high-concentration wastewater exits from the coagulation sedimentation tank, it can be mixed with domestic water and initial rainwater from the low-concentration wastewater collection tank and then enter the equalization tank for further biochemical treatment.

[0017] Furthermore, a reflux pump is provided between the hydrolysis sedimentation tank and the hydrolysis acidification tank.

[0018] The sludge lost from the hydrolysis acidification tank with the water flow can be returned to the hydrolysis acidification tank via the return pump in the hydrolysis sedimentation tank, thus ensuring the stability of the hydrolysis sludge concentration in the hydrolysis sedimentation tank.

[0019] Furthermore, a second reflux pump is provided between the anaerobic sedimentation tank and the UASB reactor.

[0020] The sludge lost from the UASB reactor with the water flow can be returned to the UASB reactor in the anaerobic sedimentation tank by the second return pump, ensuring the stability of the anaerobic sludge concentration in the UASB reactor.

[0021] Furthermore, a reflux pump is provided between the secondary sedimentation tank and the anoxic A tank.

[0022] The activated sludge in the aerobic O tank undergoes sludge-water separation in the secondary sedimentation tank, and the sludge is returned to the anoxic A tank via a return pump, ensuring a stable sludge concentration in the anoxic A tank and achieving stable operation of the biochemical system.

[0023] The high-concentration wastewater treatment system provided by this utility model can fully decompose the recalcitrant substances in the high-concentration wastewater generated by the production unit into small-molecule, easily biodegradable substances, thereby improving the biodegradability of the wastewater. By transporting the spray absorption liquid from the tail gas alkaline scrubbing tower and the biogas desulfurization tower to the aerobic O2 tank, the sulfur-containing substances are oxidized in the aerobic environment of the aerobic O2 tank. Finally, the sulfur element is discharged outside the system in the form of sulfate, preventing the accumulation of sulfur element in the wastewater treatment system. This improves the treatment effect of the biogas desulfurization tower and the tail gas alkaline scrubbing tower, and the hydrogen sulfide in the exhaust gas always meets the emission standards. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the high-concentration wastewater treatment system of this utility model.

[0025] Explanation of markings in the diagram:

[0026] 1. High-concentration wastewater collection tank; 2. Fenton reaction tank 1; 3. Fenton reaction tank 2; 4. Fenton reaction tank 3; 5. Fenton reaction tank 4; 6. Coagulation sedimentation tank; 7. Low-concentration wastewater collection tank; 8. Equalization tank; 9. Hydrolysis acidification tank; 10. Return pump 1; 11. Hydrolysis sedimentation tank; 12. Water distribution tank; 13. UASB reaction tank; 14. Anaerobic sedimentation tank; 15. Anoxic A tank; 16. Aerobic O tank; 17. Secondary sedimentation tank; 18. Effluent tank; 19. Water seal tank; 20. Biogas desulfurization tower; 21. Flare equipment; 22. Return pump 3; 23. Tail gas alkaline spray tower; 24. Biological deodorization tower; 25. Dehydration tank; 26. Activated carbon adsorption box; 27. Exhaust fan; 28. Exhaust stack; 29. ​​Return pump 2. Detailed Implementation

[0027] To better understand the purpose, structure, and function of this utility model, a more detailed description of this utility model is provided below with reference to the accompanying drawings.

[0028] Example:

[0029] like Figure 1 As shown, a high-concentration wastewater treatment system includes a wastewater treatment system, a biogas treatment system, and a tail gas treatment system. The wastewater treatment system includes wastewater treatment units connected sequentially by wastewater pipelines. These wastewater treatment units are, in sequence, a high-concentration wastewater collection tank 1, a Fenton reaction tank 1 2, a Fenton reaction tank 2 3, a Fenton reaction tank 3 4, a Fenton reaction tank 4 5, a coagulation sedimentation tank 6, an equalization tank 8, a hydrolysis acidification tank 9, a hydrolysis sedimentation tank 11, a water distribution tank 12, a UASB reaction tank 13, an anaerobic sedimentation tank 14, an anoxic A tank 15, an aerobic O tank 16, a secondary sedimentation tank 17, and an effluent tank 18. The equalization tank 8 is connected to a low-concentration wastewater collection tank 7. Each wastewater treatment unit of the treatment system is equipped with a top gas collection hood, which is connected to the tail gas treatment system via pipelines; the UASB reactor 13 is connected to the biogas treatment system via pipelines; the tail gas treatment system includes a tail gas alkaline spray tower 23, a biological deodorization tower 24, a dehydration tank 25, an activated carbon adsorption box 26, an induced draft fan 27, and an exhaust stack 28, which are connected in sequence via gas pipelines; the biogas treatment system includes a water seal tank 19, a biogas desulfurization tower 20, and a flare device 21, which are connected in sequence via gas pipelines; the spray liquid outlets of the tail gas alkaline spray tower 23 and the biogas desulfurization tower 20 are connected to the aerobic O tank 16 via pipelines.

[0030] Furthermore, the bottom of the high-concentration wastewater collection tank 1 is equipped with a perforated aeration pipe, and the Fenton reaction tank 1 2, Fenton reaction tank 2 3, Fenton reaction tank 3 4 and Fenton reaction tank 4 5 are all equipped with metering pumps. A return pump 10 is provided between the hydrolysis sedimentation tank 11 and the hydrolysis acidification tank 9, and a return pump 29 is provided between the anaerobic sedimentation tank and the UASB reaction tank. A return pump 3 22 is provided between the secondary sedimentation tank 17 and the anoxic A tank 15.

[0031] The treatment process for high-concentration wastewater is as follows:

[0032] (1) The high-concentration wastewater discharged from each production unit is collected and enters the high-concentration wastewater collection tank 1. The high-concentration wastewater is mixed and homogenized through the perforated aeration pipe arranged at the bottom of the high-concentration wastewater collection tank 1.

[0033] (2) Wastewater is pumped through four Fenton reaction tanks in sequence. Concentrated sulfuric acid is added to Fenton reaction tank 1 (2) by metering pump to adjust the pH to between 3 and 4. At the same time, ferrous sulfate is added as a catalyst for generating ·OH free radicals.

[0034] (3) After the wastewater enters the Fenton reaction tank 2 from the Fenton reaction tank 1, hydrogen peroxide is added by metering pump. Under the catalysis of ferrous iron, ·OH free radicals are generated to decompose the substances in the high-concentration wastewater that are difficult to biodegrade.

[0035] (4) After the wastewater enters the Fenton reaction tank 3 from the Fenton reaction tank 2, NaOH liquid alkali agent is added by metering pump to adjust the pH to between 7 and 8. The Fe(OH)3 colloid produced has flocculation and adsorption functions and can also remove some organic matter in the water.

[0036] (5) After the wastewater enters the Fenton reaction tank 4 from the Fenton reaction tank 3, PAC and PAM agents are added by metering pump to further flocculate the suspended colloidal flocs in the wastewater into large particles, which are easier to separate from the wastewater.

[0037] (6) After the wastewater enters the coagulation sedimentation tank 6 from the Fenton reaction tank 5, the large flocs complete the mud-water separation process by gravity sedimentation.

[0038] (7) After the wastewater is discharged from the coagulation sedimentation tank 6, it enters the equalization tank 8 together with the domestic water and initial rainwater in the low-concentration wastewater collection tank 7. After being mixed and homogenized in the equalization tank 8, it undergoes subsequent biochemical treatment.

[0039] (8) In the hydrolysis acidification tank 9, under the action of hydrolysis and acid-producing bacteria, the large molecular organic matter is degraded into small molecular organic matter, and the biodegradability of the wastewater is further improved; the sludge lost with the water flow in the hydrolysis acidification tank 9 is returned to the hydrolysis acidification tank 9 in the hydrolysis sedimentation tank 11 by the return pump 10, so as to ensure the stability of the concentration of hydrolyzed sludge in the hydrolysis acidification tank 9.

[0040] (9) After the wastewater enters the UASB reactor 13 through the water distribution tank 12, the organic matter further undergoes the stages of acetic acid production and methanogenesis under the action of anaerobic bacteria. The organic matter in the wastewater is degraded to a large extent, and the COD drops significantly. Then, the wastewater enters the anoxic A tank 15 and the aerobic O tank 16 through the anaerobic sedimentation tank 14 for deep treatment. The COD, ammonia nitrogen and other indicators meet the environmental protection emission standards. The sludge lost by the water flow in the UASB reactor is returned to the UASB reactor in the anaerobic sedimentation tank by the return pump 29 to ensure the stability of the anaerobic sludge concentration in the UASB reactor. The activated sludge in the aerobic O tank 16 undergoes sludge-water separation in the secondary sedimentation tank 17. The treated wastewater is discharged through the effluent tank 18, and the sludge is returned to the anoxic A tank 15 by the return pump 22 to ensure the stability of the sludge concentration in the anoxic A tank 15 and realize the stable operation of the biological system.

[0041] (10) In the high-concentration wastewater treatment process, the waste gas generated by each pool is collected by the gas collection hood on the top of each pool and enters the tail gas collection system through the pipeline. After the tail gas alkaline spray tower 23 for alkaline neutralization, biological deodorization tower 24 for biodegradation, dehydration tank 25 for dehydration, and activated carbon adsorption box 26 for adsorption, the odorous gases such as hydrogen sulfide and ammonia in the waste gas are purified and treated. After being blown by the induced draft fan 27, it is discharged through the exhaust stack 28 to meet the standards. The biogas generated by the UASB pool enters the biogas treatment system through the pipeline, enters the biogas desulfurization tower 20 through the water seal tank 19, and removes the hydrogen sulfide in the waste gas by alkaline spray washing. Finally, the biogas enters the flare equipment 21 for harmless treatment. The waste gas is purified through the above process and finally meets the emission standards.

[0042] (11) The biogas desulfurization tower 20 and the tail gas alkaline spray tower 23 absorb hydrogen sulfide to form a saturated spray absorption liquid, which is then transported to the aerobic O tank 16. The sulfur-containing substances are oxidized in the aerobic environment of the aerobic O tank 16, and the sulfur element is finally discharged outside the system in the form of sulfate.

[0043] The high-concentration wastewater treatment system provided by this utility model can decompose the recalcitrant substances in the high-concentration wastewater generated by the production unit into small-molecule, easily biodegradable substances, thereby improving the biodegradability of the wastewater. By transporting the spray absorption liquid from the tail gas alkaline scrubbing tower 23 and the biogas desulfurization tower 20 to the aerobic O tank 16, the sulfur-containing substances are oxidized in the aerobic environment of the aerobic O tank 16. Finally, the sulfur element is discharged outside the system in the form of sulfate, so that the sulfur element will not accumulate in the wastewater treatment system, thereby improving the treatment effect of the biogas desulfurization tower 20 and the tail gas alkaline scrubbing tower 23. The hydrogen sulfide in the exhaust gas can always meet the emission standards.

[0044] It is understood that the present invention is described by way of certain embodiments, and those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. Furthermore, under the guidance of the present invention, these features and embodiments may be modified to suit specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are intended to be protected by the present invention.

Claims

1. A high-concentration wastewater treatment system, characterized in that, This includes wastewater treatment systems, biogas treatment systems, and exhaust gas treatment systems; The wastewater treatment system includes wastewater treatment units connected sequentially by wastewater pipelines. These wastewater treatment units are, in sequence, a high-concentration wastewater collection tank, a Fenton reaction tank, a coagulation sedimentation tank, a hydrolysis acidification tank, a hydrolysis sedimentation tank, a water distribution tank, a UASB reaction tank, an anaerobic A tank, an aerobic O tank, a secondary sedimentation tank, and an effluent tank. Each wastewater treatment unit is equipped with a top-mounted gas collection hood, which is connected to the tail gas treatment system via pipelines. The UASB reaction tank is connected to the biogas treatment system via pipelines. The exhaust gas treatment system includes an exhaust gas alkaline spray tower, a biological deodorization tower, a dehydration tank, an activated carbon adsorption box, an induced draft fan, and an exhaust stack, all connected in sequence by gas pipelines; the biogas treatment system includes a water seal tank, a biogas desulfurization tower, and a flare device, all connected in sequence by gas pipelines; the spray liquid outlets of the exhaust gas alkaline spray tower and the biogas desulfurization tower are connected to the aerobic O2 pool via pipelines.

2. The high-concentration wastewater treatment system according to claim 1, characterized in that, The bottom of the high-concentration wastewater collection tank is equipped with perforated aeration pipes.

3. The high-concentration wastewater treatment system according to claim 1, characterized in that, It includes multiple Fenton reaction cells.

4. The high-concentration wastewater treatment system according to claim 3, characterized in that, It includes Fenton reaction pool one, Fenton reaction pool two, Fenton reaction pool three and Fenton reaction pool four.

5. The high-concentration wastewater treatment system according to claim 4, characterized in that, Metering pumps are provided in Fenton reaction tank 1, Fenton reaction tank 2, Fenton reaction tank 3 and Fenton reaction tank 4.

6. The high-concentration wastewater treatment system according to claim 1, characterized in that, An equalization tank is provided between the coagulation sedimentation tank and the hydrolysis acidification tank, and the equalization tank is connected to a low-concentration wastewater collection tank.

7. The high-concentration wastewater treatment system according to claim 1, characterized in that, A reflux pump is provided between the hydrolysis sedimentation tank and the hydrolysis acidification tank.

8. The high-concentration wastewater treatment system according to claim 7, characterized in that, A second reflux pump is provided between the anaerobic sedimentation tank and the UASB reactor.

9. The high-concentration wastewater treatment system according to claim 7, characterized in that, A reflux pump is installed between the secondary sedimentation tank and the anoxic A tank.

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