Efficient sewage treatment and resource utilization system for fine chemical industry park

Abstract

The utility model discloses an efficient sewage treatment and resource utilization system for a fine chemical industry park, belongs to the technical field of sewage treatment, and solves the problems that sewage treatment in the fine chemical industry park does not reach the standard and water supply is insufficient. The system comprises a water quality monitoring and adjusting tank, an advanced oxidation unit, a hydrolysis acidification tank, a biological tank, a secondary sedimentation tank, an efficient sedimentation tank, an ozone oxidation tank, a biological aerated filter, a filter, an ultraviolet disinfection water storage tank, a first ultrafiltration system, a first reverse osmosis system, a softening and hardness removing device, a sand filter tank, ion exchange resin and a second ultrafiltration system which are connected in sequence, a second reverse osmosis system, a nanofiltration device and a third reverse osmosis system; the nanofiltration device is connected with a first evaporator; the third reverse osmosis system is connected with a second evaporator. According to the utility model, the biodegradability is improved, the efficient removal of N and P is realized, the standard removal of COD (Chemical Oxygen Demand) of effluent is ensured, the evaporative crystallization operation cost is reduced, and the resource utilization of sewage is realized.

Description

Technical Field

[0001] This utility model belongs to the field of wastewater treatment technology, specifically relating to a system for efficient treatment and resource utilization of wastewater in a fine chemical industrial park. Background Technology

[0002] In recent years, in order to attract foreign investment, optimize industrial resources, and promote economic development, various regions in my country have successively built a number of fine chemical industrial parks in various forms, such as economic and technological development zones and technology demonstration zones. Against the backdrop of the rapid advancement of fine chemical industrial park construction across the country, the supporting centralized wastewater treatment projects have become particularly important to prevent them from becoming major sources of industrial water pollution.

[0003] Wastewater from fine chemical industrial parks is complex in composition and varies greatly in quality. It often contains toxic and harmful substances, has high salt content, and fluctuates significantly in quality, differing greatly from urban sewage. Some fine chemical industrial parks rely on municipal wastewater treatment plants to treat industrial wastewater exceeding regulatory requirements, impacting the stable operation of these plants. Furthermore, many parks' wastewater treatment facilities use conventional municipal wastewater treatment processes, which are unsuitable for industrial wastewater, resulting in poor treatment effectiveness and frequent instances of substandard effluent.

[0004] As major consumers of water resources, enterprises in industrial parks are often constrained by water availability, and water resource fees are a significant component of their daily operating costs. Furthermore, fine chemical industrial parks typically face challenges in disposing of treated wastewater due to limitations imposed by the water environment capacity of receiving water bodies. Therefore, insufficient water supply and wastewater disposal have become the most critical issues hindering the healthy development of fine chemical industrial parks, making the implementation of wastewater reuse programs of significant practical importance. Utility Model Content

[0005] The purpose of this invention is to provide a system for efficient treatment and resource utilization of wastewater in fine chemical industrial parks, in order to solve the problems of substandard wastewater treatment and insufficient water supply in fine chemical industrial parks.

[0006] The technical solution of this utility model is: a high-efficiency wastewater treatment and resource utilization system for a fine chemical industrial park, comprising, in sequence, a water quality monitoring and conditioning tank, an advanced oxidation unit, a hydrolysis acidification tank, a biological tank, a secondary sedimentation tank, a high-efficiency sedimentation tank, an ozone oxidation tank, an aerated biological filter, a filter, an ultraviolet disinfection storage tank, a first ultrafiltration system, a first reverse osmosis system, a softening and hardening removal device, a sand filter, an ion exchange resin, a second ultrafiltration system, a second reverse osmosis system, a nanofiltration device, and a third reverse osmosis system; the nanofiltration device is connected to a first evaporator; the third reverse osmosis system is connected to a second evaporator.

[0007] As a further improvement of this utility model, it also includes a water recycling tank, and the first reverse osmosis system, the second reverse osmosis system and the third reverse osmosis system are respectively connected to the water recycling tank.

[0008] As a further improvement of this utility model, the water quality monitoring and conditioning tank is connected to an emergency tank.

[0009] The beneficial effects of this utility model are:

[0010] 1. This utility model provides a system suitable for wastewater treatment in fine chemical industrial parks. Addressing the characteristics of wastewater in fine chemical industrial parks, such as a high proportion of recalcitrant CODcr, the presence of toxic and harmful substances, high salt content, and significant water quality fluctuations, the system enhances pretreatment through an advanced oxidation unit to reduce biotoxicity and utilizes a hydrolysis acidification tank to improve biodegradability. A secondary biological treatment tank in the biological tank achieves efficient removal of N and P. An ozone oxidation tank, in conjunction with an aerated biological filter, ensures that the effluent COD meets standards. A three-stage reverse osmosis system concentration process improves water production rate, reduces concentrate volume, and lowers the operating costs of evaporation and crystallization.

[0011] 2. This utility model can reduce the TDS in wastewater from a fine chemical industrial park to below 1000 mg / L, COD to below 30 mg / L, and TN to below 15 mg / L. The permeate from the three-stage reverse osmosis system is collected in a reuse tank, disinfected, and then returned to the fine chemical industrial park for reuse, realizing the resource utilization of wastewater, achieving near-zero wastewater discharge, and solving the problem of insufficient water supply in the fine chemical industrial park. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model.

[0013] In the diagram: 1-Emergency tank; 2-Water quality monitoring and conditioning tank; 3-Advanced oxidation unit; 4-Hydrolysis acidification tank; 5-Biological tank; 6-Secondary sedimentation tank; 7-High-efficiency sedimentation tank; 8-Ozone oxidation tank; 9-Aerated biological filter; 10-Filter; 11-Ultraviolet disinfection storage tank; 12-First ultrafiltration system; 13-First reverse osmosis system; 14-Softening and hardening removal device; 15-Sand filter tank; 16-Ion exchange resin; 17-Second ultrafiltration system; 18-Second reverse osmosis system; 19-Nanofiltration device; 20-Third reverse osmosis system; 21-First evaporator; 22-Second evaporator; 23-Reclaimed water tank. Detailed Implementation

[0014] The present invention will now be described in detail with reference to the accompanying drawings.

[0015] like Figure 1As shown, a high-efficiency wastewater treatment and resource utilization system for a fine chemical industrial park includes, in sequence, a water quality monitoring and conditioning tank 2, an advanced oxidation unit 3, a hydrolysis acidification tank 4, a biological tank 5, a secondary sedimentation tank 6, a high-efficiency sedimentation tank 7, an ozone oxidation tank 8, an aerated biological filter 9, a filter 10, an ultraviolet disinfection storage tank 11, a first ultrafiltration system 12, a first reverse osmosis system 13, a softening and hardening removal device 14, a sand filter tank 15, an ion exchange resin 16, a second ultrafiltration system 17, a second reverse osmosis system 18, a nanofiltration device 19, and a third reverse osmosis system 20; the nanofiltration device 19 is connected to a first evaporator 21; and the third reverse osmosis system 20 is connected to a second evaporator 22.

[0016] It also includes a recycled water tank 23, and the first reverse osmosis system 13, the second reverse osmosis system 18 and the third reverse osmosis system 20 are respectively connected to the recycled water tank 23.

[0017] Water quality monitoring and regulation tank 2 is connected to emergency tank 1.

[0018] Wastewater pretreated by the enterprise, meeting relevant standards (relevant industrial water pollutant discharge standards or local connection standards), is transported via pressure pipeline to water quality monitoring and equalization tank 2 for water quality monitoring and flow regulation. The effluent from water quality monitoring and equalization tank 2 then enters advanced oxidation unit 3, where its strong oxidizing properties reduce biotoxicity and lower recalcitrant COD. crThe proportions ensure the safe operation of the subsequent biological tanks; the effluent from the advanced oxidation unit 3 enters the hydrolysis acidification tank 4, where large molecules are hydrolyzed into smaller molecules, improving the biodegradability of the wastewater; the effluent from the hydrolysis acidification tank 4 enters the biological tank 5 for nitrogen and phosphorus removal; the effluent from the biological tank 5 enters the secondary sedimentation tank 6 for sludge-water separation; the effluent from the secondary sedimentation tank 6 enters the high-efficiency sedimentation tank 7, which reduces the consumption of ozone by suspended solids (SS) and the organic load of the ozone oxidation tank 8, and also achieves chemical phosphorus removal; the effluent from the high-efficiency sedimentation tank 7 enters the ozone oxidation tank 8 and the aerated biological filter 9 in sequence to further enhance the removal of recalcitrant CODcr; the effluent from the aerated biological filter 9 enters the filter 10 to ensure the SS effect; the effluent from the filter 10 passes through the ultraviolet disinfection storage tank 11 and then enters the first ultrafiltration system 12 and the first reverse osmosis system 13 for treatment, with the permeate entering the reclaimed water tank 23; the concentrate from the first reverse osmosis system 13 enters the softening and hardening removal device 1. 4. Reduce the risk of system scaling: The effluent from the softening and hardening device 14 enters the sand filter tank 15 to trap residual colloids and suspended solids; the effluent from the sand filter tank 15 enters the ion exchange resin 16 for deep hardening, preventing scaling in subsequent membrane systems and evaporation crystallization, and ensuring stable system operation; the effluent after ion exchange is pressurized and enters the second ultrafiltration system 17 and the second reverse osmosis system 18 to further improve the water production rate, and the produced water enters the recycled water tank 23; the concentrated water produced by the second reverse osmosis system 18 enters the nanofiltration device 19, utilizing the selective permeability of nanofiltration membrane elements to monovalent and divalent ions to increase the proportion of sodium sulfate on the concentrated water side, and the concentrated water enters the first evaporator 21 for final concentration, producing sodium sulfate crystals and miscellaneous salts; the produced water from the nanofiltration device 19 enters the third reverse osmosis system 20 for further concentration, and the produced water enters the recycled water tank 23, and the concentrated water enters the second evaporator 22 for final concentration, producing sodium chloride crystals and miscellaneous salts. After chlorination disinfection, the recycled water in the recycled water tank 23 is returned to the fine chemical industrial park for reuse.

[0019] The companies in the park use a "one company, one pipe" method to transport wastewater. The structure of the water quality monitoring and regulation tank 2 is as described in patent ZL202322420603.4. It adopts a stacked construction mode, which matches the "one company, one pipe" drainage mode and meets the requirements for water quality monitoring and water volume regulation under the "one company, one pipe" drainage mode.

[0020] Advanced oxidation unit 3 employs ozone catalytic oxidation, Fenton oxidation, or Fenton oxidation coupled with iron-carbon micro-electrolysis.

[0021] The hydraulic retention time of the hydrolysis acidification tank 4 is more than 12 hours, which maximizes the treatment potential of the downstream biological tank 5.

[0022] Biological pond 5 adopts a multi-stage or five-stage AO process with high nitrogen and phosphorus removal efficiency.

[0023] The hydraulic load of the secondary sedimentation tank 6 and the high-efficiency sedimentation tank 7 shall be taken from the lower limit of the standard.

[0024] Depending on the TN concentration in the incoming water, filter 10 can be a V-type filter or a denitrification deep bed filter.

[0025] The inlet and outlet water system of the accident pool 1 is linked with the water quality of the water quality monitoring and regulating pool 2. Monitoring instruments for characteristic pollutants and risk water quality indicators of industrial wastewater are installed at the inlet of the water quality monitoring and regulating pool 2. When the inlet water quality exceeds the set value, the valve automatically switches to allow the wastewater exceeding the standard to enter the accident pool 1.

[0026] The softening and hardening device 14 adopts a chemical crystallization circulating granulation fluidized bed.

[0027] The first reverse osmosis system 13, the second reverse osmosis system 18, and the third reverse osmosis system 20 constitute a reclaimed water treatment unit. Through the three-stage reverse osmosis system concentration process, the water production rate is increased and the concentrate volume is reduced.

[0028] The UV disinfection water storage tank 11 has both UV disinfection and water storage functions, and can play a buffer role. It has a water storage capacity of 12~24 hours and is also equipped with emergency facilities.

[0029] When the TDS in the concentrate of nanofiltration unit 19 and the third reverse osmosis system 20 is ≥100,000 mg / L and COD is ≥1,000 mg / L, DTRO and DTNF disc-type reverse osmosis membrane elements and nanofiltration membrane elements with strong antifouling properties are adopted.

[0030] When the TDS on the concentrate side of nanofiltration unit 19 is ≤8%, a reverse osmosis system can be added in series on the concentrate side of nanofiltration unit 19 to increase the concentration ratio.

[0031] In response to the problem that the wastewater discharged from enterprises in fine chemical industrial parks has high levels of recalcitrant CODcr, poor biodegradability, and contains a certain concentration of toxic and harmful substances, and that conventional treatment processes in urban wastewater treatment plants are unable to cope with such complex water quality and achieve resource utilization, this utility model, through reasonable design, forms a wastewater treatment system that ensures treatment effectiveness. The treated water can be returned to the fine chemical industrial park for reuse, realizing the resource utilization of the park's wastewater.

Claims

1. A system for efficient treatment and resource utilization of wastewater in a fine chemical industrial park, characterized in that: The water quality monitoring and adjusting tank (2), the advanced oxidation unit (3), the hydrolysis acidification tank (4), the biological tank (5), the secondary sedimentation tank (6), the high-efficiency sedimentation tank (7), the ozone oxidation tank (8), the biological aerated filter (9), the filter tank (10), the ultraviolet disinfection storage tank (11), the first ultrafiltration system (12), the first reverse osmosis system (13), the softening and hard removal device (14), the sand filter tank (15), the ion exchange resin (16), the second ultrafiltration system (17), the second reverse osmosis system (18), the nanofiltration device (19) and the third reverse osmosis system (20) are sequentially connected.

2. The system for efficient treatment and resource utilization of wastewater in a fine chemical industrial park according to claim 1, characterized in that: The first reverse osmosis system (13), the second reverse osmosis system (18) and the third reverse osmosis system (20) are connected to the reuse water tank (23).

3. The system for efficient treatment and resource utilization of wastewater in a fine chemical industrial park according to claim 1 or 2, characterized in that: The water quality monitoring and adjusting tank (2) is connected with the emergency tank (1).

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