Degradation-resistant organic matter wastewater deep purification treatment system

Abstract

The utility model relates to a deep purification treatment system for degradation-resistant organic matter wastewater, which comprises a pretreatment unit, a persulfate advanced oxidation unit, a biological treatment unit, a membrane separation deep purification treatment unit, a disinfection tank and a sludge treatment unit, and is characterized in that the pretreatment unit comprises a bar screen machine, a rotational flow grit chamber and a pH (Potential of Hydrogen) regulating tank; the persulfate advanced oxidation unit comprises a persulfate advanced oxidation reactor, a persulfate adding device and a catalyst adding device, the biological treatment unit comprises an anaerobic tank, an anoxic MBBR (Moving Bed Biofilm Reactor) tank, an aerobic MBBR tank and a secondary sedimentation tank, and the membrane separation deep purification treatment unit comprises a coagulative precipitation tank, an intermediate water tank, an ultrafiltration module and a reverse osmosis module. According to the utility model, the traditional biological treatment process is combined with physical and chemical treatment technologies such as persulfate advanced oxidation and membrane separation, so that the treatment efficiency of refractory organic wastewater can be effectively improved, the quality of effluent is improved, and the industrial recycling requirement is met.

Description

Technical Field

[0001] The utility model relates to the field of water treatment technology, and in particular to a wastewater treatment system integrating persulfate advanced oxidation, biodegradation and membrane separation technologies. The utility model is particularly suitable for the treatment and reuse of industrial wastewater containing antibiotics, heterocyclic compounds, halogenated hydrocarbons and other refractory organic substances generated in the pharmaceutical, pesticide, dye and other industries. Background Art

[0002] With the rapid development of the pharmaceutical industry, persistent organic pollutants such as antibiotics, benzene rings, and polychlorinated biphenyls (PCBs) remain in large quantities in water bodies. Due to their persistence, biotoxicity, and the risk of transmitting drug-resistant genes, they pose a serious threat to the ecological environment and human health. Traditional wastewater treatment processes (such as activated sludge and coagulation sedimentation) are primarily designed for conventional pollutants and are difficult to achieve efficient degradation of these new pollutants.

[0003] Current treatment technologies for recalcitrant organic pollutants primarily include physical and chemical methods and biological treatment. Physical and chemical methods primarily include adsorption, coagulation, and chemical oxidation, but each of these technologies has varying degrees of limitations. While adsorption can rapidly concentrate pollutants, it involves only phase transfer, requiring subsequent treatment and resulting in high costs. Furthermore, adsorption performance is significantly affected by pollutant concentration and water quality conditions (such as pH and coexisting ions). Coagulation suffers from poor selectivity for organic pollutants, produces large amounts of sludge, and is prone to secondary pollution. Traditional chemical oxidation relies on hydroxyl radicals (•OH), which have a short half-life (<1 μs), a narrow pH range (requiring acidic conditions), and low oxidant utilization. Biological treatment, primarily the activated sludge process, can remove some organic matter, but microorganisms are susceptible to inhibition by organic matter, such as antibiotics, leading to fluctuations in treatment efficiency. Furthermore, antibiotics adsorbed by sludge may enter the environment through backflow, causing secondary pollution.

[0004] In recent years, advanced oxidation technology has attracted much attention due to its advantages of high efficiency, rapidity and thorough oxidation reaction. Among them, persulfate activation method has attracted much attention due to the sulfate radical (SO4 - •) has strong oxidation ability and long half-life (30-40 μs) and has broad application prospects, but the single oxidation process is easily affected by Cl in water. - , humic acid, and other pollutants, and may generate toxic intermediates. Although membrane separation technology can efficiently intercept small molecule pollutants and has a wide range of water quality applications, when applied to wastewater treatment processes, membrane fouling is a prominent problem and operating costs are high.

[0005] In summary, the current technical bottleneck lies in the independent operation of single physical, chemical and biological processes, which fail to achieve synergistic efficiency; the antibiotics enriched in the sludge by adsorption and biological methods are not completely degraded, posing a risk of secondary pollution; the adaptability to sewage water quality conditions is poor, and the treatment efficiency drops sharply when encountering complex water such as high salt and multiple coexisting ions. Summary of the Invention

[0006] In view of the problem that wastewater containing antibiotics and other difficult-to-degrade organic matter is becoming increasingly complex and it is difficult to treat it to meet emission standards using a single process, the utility model combines traditional biological treatment processes with physical and chemical treatment technologies such as persulfate advanced oxidation and membrane separation, and applies them to the treatment of wastewater containing antibiotics and other difficult-to-degrade organic matter, thereby improving the treatment efficiency of wastewater containing antibiotics and the water quality of the effluent to meet industrial reuse requirements.

[0007] The utility model provides a deep purification treatment system for wastewater with refractory organic matter, comprising a pretreatment unit, a persulfate advanced oxidation unit, a biological treatment unit, a membrane separation deep purification treatment unit, a disinfection tank, and a sludge treatment unit. The utility model is characterized in that: the pretreatment unit comprises a grid decontamination machine, a cyclone grit chamber, and a pH adjustment tank; the persulfate advanced oxidation unit comprises a persulfate advanced oxidation reactor, a persulfate adding device, and a catalyst adding device; the biological treatment unit comprises an anaerobic tank, an anoxic MBBR tank, an aerobic MBBR tank, and a secondary sedimentation tank; the membrane separation deep purification treatment unit comprises a coagulation sedimentation tank, an intermediate water tank, an ultrafiltration module, and a reverse osmosis module; the pretreatment unit, the persulfate advanced oxidation unit, the biological treatment unit, the membrane separation deep purification treatment unit, and the disinfection tank are connected in sequence through corrosion-resistant pipes with flow control valves.

[0008] Furthermore, the anoxic MBBR pool and the aerobic MBBR pool are both equipped with a submersible mixer and an aeration device. The dissolved oxygen in the anoxic MBBR pool is 0.2-0.5 mg / L, and the dissolved oxygen in the aerobic MBBR pool is 2.5-4.0 mg / L. The anoxic MBBR pool and the aerobic MBBR pool are both filled with MBBR carriers with a filling rate of 30%-40%. The MBBR carrier is made of polyethylene with a density of 0.94-0.96 g / cm 3 .

[0009] Furthermore, an internal reflux pipe and an internal reflux pump are provided between the anoxic MBBR tank and the aerobic MBBR tank, for the sludge in the aerobic MBBR tank to flow back into the anoxic MBBR tank, and an external reflux pipe and an external reflux pump are provided between the anaerobic tank and the secondary sedimentation tank, for the sludge in the secondary sedimentation tank to flow back into the anaerobic tank.

[0010] Furthermore, the reverse osmosis module contains two-stage reverse osmosis membranes, a low-pressure reverse osmosis membrane and a high-pressure reverse osmosis membrane. The operating pressure of the low-pressure reverse osmosis membrane is 1.0-1.5 MPa, and the high-pressure reverse osmosis membrane is a high-fouling resistance reverse osmosis membrane with an operating pressure of 4.0-5.0 MPa.

[0011] The utility model combines traditional biological treatment processes with physical and chemical treatment technologies such as persulfate advanced oxidation and membrane separation, and utilizes the synergistic effect of advanced oxidation-biological treatment-membrane separation deep purification treatment to improve the treatment efficiency of refractory organic wastewater, improve the effluent water quality, and meet industrial reuse requirements. The utility model has a wide range of water quality applications, is less affected by upstream sewage discharge, has stable water quality, and can effectively degrade refractory organic matter such as antibiotics in sewage, solving the secondary pollution problem caused by their enrichment in sludge. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is the process flow chart of this utility model. DETAILED DESCRIPTION

[0013] The present invention will be described in detail below with reference to the embodiments and accompanying drawings.

[0014] like Figure 1 As shown, a deep purification treatment system for refractory organic wastewater includes a pretreatment unit 1, a persulfate advanced oxidation unit 2, a biological treatment unit 3, a membrane separation deep purification treatment unit 4, a disinfection tank 5, and a sludge treatment unit 6, characterized in that: the pretreatment unit 1 includes a screen cleaner 11, a cyclone grit chamber 12, and a pH adjustment tank 13; the persulfate advanced oxidation unit 2 includes a persulfate advanced oxidation reactor 21, a persulfate addition device 22, and a catalyst addition device 23; the biological treatment unit 3 includes an anaerobic tank 31, an anoxic MBBR tank 32, an aerobic MBBR tank 33, and a secondary sedimentation tank 34; the membrane separation deep purification treatment unit 4 includes a coagulation sedimentation tank 41, an intermediate water tank 42, an ultrafiltration module 43, and a reverse osmosis module 44; the pretreatment unit 1, persulfate advanced oxidation unit 2, biological treatment unit 3, membrane separation deep purification treatment unit 4, and disinfection tank 5 are connected in sequence by corrosion-resistant pipes with flow control valves.

[0015] The anoxic MBBR pool 32 and the aerobic MBBR pool 33 are both equipped with a submersible mixer and an aeration device. The dissolved oxygen in the anoxic MBBR pool 32 is 0.2-0.5 mg / L, and the dissolved oxygen in the aerobic MBBR pool 33 is 2.5-4.0 mg / L. The anoxic MBBR pool 32 and the aerobic MBBR pool 33 are both filled with MBBR carriers with a filling rate of 30%-40%. The MBBR carrier is made of polyethylene with a density of 0.94-0.96 g / cm 3; An internal reflux pipe and an internal reflux pump are provided between the anoxic MBBR tank 32 and the aerobic MBBR tank 33, for the sludge in the aerobic MBBR tank 33 to flow back into the anoxic MBBR tank 32, and an external reflux pipe and an external reflux pump are provided between the anaerobic tank 31 and the secondary sedimentation tank 34, for the sludge in the secondary sedimentation tank 34 to flow back into the anaerobic tank 31; the reverse osmosis module 44 contains two-stage reverse osmosis membranes, namely, a low-pressure reverse osmosis membrane and a high-pressure reverse osmosis membrane. The operating pressure of the low-pressure reverse osmosis membrane is 1.0-1.5 MPa, and the high-pressure reverse osmosis membrane is a high-fouling anti-reverse osmosis membrane with an operating pressure of 4.0-5.0 MPa. The clean water produced by the low-pressure reverse osmosis membrane and the high-pressure reverse osmosis membrane enters the disinfection tank 5, and after disinfection, it is transported to the reclaimed water user. The concentrated water produced by the low-pressure reverse osmosis membrane enters the high-pressure reverse osmosis membrane for further desalination and concentration. The concentrated water discharged from the high-pressure reverse osmosis membrane is used for flushing the ultrafiltration module 43, as well as for road dust reduction, environmental sanitation cleaning and other miscellaneous purposes.

[0016] During operation, the refractory organic wastewater is first deslagging in the screen decontamination machine 11, desanding in the cyclone grit chamber 12, and adjusting the pH value to 6.5-7.5 in the pH adjustment tank. It then enters the persulfate advanced oxidation reactor 21. Under the action of persulfate and catalyst, the refractory organic matter is decomposed into small molecular organic matter that is easy to biochemically treat. Then, it enters the anaerobic tank 31, the anoxic MBBR tank 32, and the aerobic MBBR tank 33 for biochemical treatment to reduce the COD, total nitrogen, ammonia nitrogen and total phosphorus contents. The supernatant after precipitation in the secondary sedimentation tank 34 enters the coagulation sedimentation tank 41, the intermediate water tank 42, the ultrafiltration module 43, and the reverse osmosis module 44 in turn to remove suspended matter, colloids, pigments, small molecular organic matter, heavy metal ions, soluble salts and other pollutants in the sewage. Then, it enters the disinfection tank 5 for sterilization and disinfection before being transported to the reclaimed water users. During the treatment process, the sludge produced by the persulfate advanced oxidation reactor 21, the secondary settling tank 34, and the coagulation sedimentation tank 41 is respectively transported to the sludge tank 61 through sludge pumps, dehydrated by the dehydration device 62, and then transported out for harmless disposal.

[0017] The above content describes the technical solution of the present invention in detail, but does not limit the scope of protection of the present invention. Ordinary technicians in this technical field can also make improvements and modifications on this basis, but these improvements and modifications are within the scope of protection of the claims of the present invention.

Claims

1. A deep purification treatment system for refractory organic wastewater, comprising a pretreatment unit, a persulfate advanced oxidation unit, a biological treatment unit, a membrane separation deep purification treatment unit, a disinfection tank, and a sludge treatment unit, characterized in that: The pretreatment unit includes a screen cleaner, a cyclone sand settling tank and a pH adjustment tank; the persulfate advanced oxidation unit includes a persulfate advanced oxidation reactor, a persulfate adding device, and a catalyst adding device; the biological treatment unit includes an anaerobic tank, an anoxic MBBR tank, an aerobic MBBR tank, and a secondary sedimentation tank; the membrane separation deep purification treatment unit includes a coagulation sedimentation tank, an intermediate water tank, an ultrafiltration module, and a reverse osmosis module; the pretreatment unit, persulfate advanced oxidation unit, biological treatment unit, membrane separation deep purification treatment unit, and disinfection tank are connected in sequence through corrosion-resistant pipes with flow control valves.

2. A deep purification treatment system for refractory organic wastewater according to claim 1, characterized in that: The anoxic MBBR pool and the aerobic MBBR pool are both equipped with a submersible mixer and an aeration device. The dissolved oxygen in the anoxic MBBR pool is 0.2-0.5 mg / L, and the dissolved oxygen in the aerobic MBBR pool is 2.5-4.0 mg / L. The anoxic MBBR pool and the aerobic MBBR pool are both filled with MBBR carriers with a filling rate of 30%-40%. The MBBR carrier is made of polyethylene with a density of 0.94-0.96 g / cm 3 .

3. The deep purification treatment system for refractory organic wastewater according to claim 1, characterized in that: An internal reflux pipe and an internal reflux pump are provided between the anoxic MBBR tank and the aerobic MBBR tank for returning the sludge in the aerobic MBBR tank to the anoxic MBBR tank. An external reflux pipe and an external reflux pump are provided between the anaerobic tank and the secondary sedimentation tank for returning the sludge in the secondary sedimentation tank to the anaerobic tank.

4. The deep purification treatment system for refractory organic wastewater according to claim 1, characterized in that: The reverse osmosis module contains two-stage reverse osmosis membranes, a low-pressure reverse osmosis membrane and a high-pressure reverse osmosis membrane. The operating pressure of the low-pressure reverse osmosis membrane is 1.0-1.5 MPa, and the high-pressure reverse osmosis membrane is a highly anti-fouling reverse osmosis membrane with an operating pressure of 4.0-5.0 MPa.

Images