High-salt and high-pollution wastewater treatment system

Abstract

The utility model provides a high-salt and high-pollution wastewater treatment system. The high-salt and high-pollution wastewater treatment system comprises a pretreatment unit, an evaporation unit, a condensate treatment unit and a sludge treatment unit, a large amount of chemical agents are not required to be added in the pretreatment process, less physicochemical sludge and crystal salt are generated, and the outward transportation and disposal cost of wastes is low; the effect of '1 + 1gt, 2' is achieved through three-dimensional electrolysis and a first-stage catalytic ozonation reaction, most toxic substances in the wastewater are thoroughly degraded, meanwhile, macromolecular refractory organics are oxidized into micromolecular substances, treatment is thorough, the risk of secondary pollution is avoided, and meanwhile the treatment load of a triple-effect evaporation system and a rear-end biochemical system is greatly reduced; the treatment process does not contain a membrane treatment technology, the overall operation is efficient and stable, and the impact load resistance is high; the device can perform reasonable reflux treatment on evaporation mother liquor, supernate and press filtrate generated in the treatment process, and utilizes the coupling relationship between procedures to reduce the treatment cost, improve the treatment efficiency and ensure up-to-standard discharge.

Description

Technical Field

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

[0002] Wastewater discharged during the production of fine chemical products (such as pharmaceuticals, dyes, and daily chemicals) is characterized by high salinity, high COD concentration, and toxicity to microorganisms, and is a typical type of recalcitrant wastewater.

[0003] For this type of wastewater, the main process currently used is a combination of physicochemical pretreatment, biological treatment, and membrane advanced treatment. This type of treatment process often has a long process flow and long retention time. At the same time, because a large amount of chemical reagents need to be added during the physicochemical reaction, it is very easy to generate a large amount of sludge, thus causing more serious environmental pollution. On the other hand, membrane treatment process has a short lifespan, high investment, and the concentrate produced also needs to be outsourced for disposal. The comprehensive treatment cost per ton of water is generally over 500 yuan.

[0004] Therefore, there is an urgent need for a high-salt, high-pollution wastewater treatment system that can solve the above problems. Utility Model Content

[0005] The purpose of this invention is to provide a high-salt, high-pollution wastewater treatment system to solve the problems existing in the prior art.

[0006] To achieve the above objectives, this utility model provides the following solution:

[0007] This utility model provides a high-salt, high-pollution wastewater treatment system, comprising:

[0008] A pretreatment unit is used to pretreat high-salt and highly polluted wastewater;

[0009] An evaporation unit, connected to the pretreatment unit, is used to evaporate the pretreated high-salt and highly polluted wastewater and return the mother liquor to the pretreatment unit.

[0010] A condensate disposal unit, connected to the pretreatment unit, is used to dispose of the evaporated condensate and discharge the qualified wastewater.

[0011] The sludge disposal unit is connected to the pretreatment unit and the condensate disposal unit, respectively, and is used to dispose of the sludge generated during the treatment process and return the supernatant and filtrate generated to the pretreatment unit.

[0012] Preferably, the pretreatment unit, the evaporation unit, the condensate disposal unit, and the sludge disposal unit are all connected to a blower for stirring, aeration, or backwashing.

[0013] Preferably, the pretreatment unit includes an equalization tank, which is connected to the raw water pipeline and to a flotation device via a booster pump. The flotation device is connected to a primary ozone catalytic oxidation reactor, which is connected to a pH equalization tank, which is connected to an FCD three-dimensional electrolysis reactor, and the FCD three-dimensional electrolysis reactor is connected to a neutralization flocculation sedimentation tank.

[0014] Preferably, both the air flotation device and the neutralization flocculation sedimentation tank are equipped with dosing devices and are connected to the sludge treatment unit.

[0015] Preferably, the FCD three-dimensional electrolytic reaction cell is filled with iron-carbon micro-electrolysis material with high catalytic activity and is equipped with a water distribution device, a gas distribution device and a backwashing device.

[0016] Preferably, an intermediate water tank is connected between the evaporation unit and the pretreatment unit.

[0017] Preferably, the condensate treatment unit includes an anaerobic tank, which is connected to a primary A / O tank, an intermediate sedimentation tank, and a secondary A / O tank. Both the primary and secondary A / O tanks are equipped with nitrification liquid reflux devices. The secondary A / O tank is connected to a secondary sedimentation tank, which is connected to a discharge pipe.

[0018] Preferably, a secondary ozone catalytic oxidation reactor is provided between the anaerobic tank and the evaporation unit, or between the intermediate sedimentation tank and the secondary A / O tank.

[0019] Preferably, both the primary ozone catalytic oxidation reactor and the secondary ozone catalytic oxidation reactor are filled with high-efficiency spherical ozone oxidation catalyst and are equipped with a high-efficiency dosing device, a water distribution device, a gas distribution device, and a backwashing device.

[0020] Preferably, the sludge treatment unit includes a sludge thickening tank, which is connected to the sludge discharge pipes of the pretreatment unit and the condensate treatment unit respectively. The sludge thickening tank is connected to a filter press, and both the sludge thickening tank and the filter press are connected to the pretreatment unit for returning the generated supernatant and filtrate to the pretreatment unit.

[0021] The present invention achieves the following beneficial technical effects compared to the prior art:

[0022] This utility model provides a high-salt, high-pollution wastewater treatment system, comprising: a pretreatment unit, an evaporation unit, a condensate disposal unit, and a sludge disposal unit. The pretreatment process requires no large-scale addition of chemical agents, resulting in less physicochemical sludge and crystalline salts, and lower waste disposal costs. Through three-dimensional electrolysis and primary ozone catalytic oxidation, a "1+1>2" effect is achieved, thoroughly degrading most toxic substances in the wastewater and oxidizing large, difficult-to-degrade organic molecules into smaller molecules, ensuring thorough treatment without secondary pollution risk. This also significantly reduces the treatment load on the triple-effect evaporation system and the downstream biochemical system. The treatment process does not involve membrane treatment technology, ensuring high overall efficiency and stability, and strong resistance to shock loads. It can rationally recirculate the evaporation mother liquor, supernatant, and filtrate generated during the treatment process, utilizing the coupling relationship between processes to reduce treatment costs, improve treatment efficiency, and ensure compliant discharge. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A process flow diagram of a high-salt, high-pollution wastewater treatment system provided by this utility model. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] The purpose of this invention is to provide a high-salt, high-pollution wastewater treatment system to solve the problems existing in the prior art.

[0027] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Example 1:

[0029] This embodiment provides a high-salt, high-pollution wastewater treatment system, such as... Figure 1 As shown, it includes:

[0030] The pretreatment unit is used to pretreat high-salt and highly polluted wastewater.

[0031] It includes an equalization tank 1, which is connected to the raw water pipeline and to a flotation device 2 via a booster pump. The flotation device 2 is connected to a primary ozone catalytic oxidation reactor 3, which is connected to a pH equalization tank 4. The pH equalization tank 4 is connected to an FCD three-dimensional electrolysis reactor 5, which is connected to a neutralization flocculation sedimentation tank 6. Both the flotation device 2 and the neutralization flocculation sedimentation tank 6 are equipped with dosing devices for adding chemicals and are connected to a sludge disposal unit to discharge the generated sludge. The FCD three-dimensional electrolysis reactor is filled with a highly catalytically active iron-carbon micro-electrolysis material, which can be the highly catalytically active iron-carbon micro-electrolysis material disclosed in Chinese Patent CN201911236372.3. It is also equipped with a water distribution device, an air distribution device, and a backwashing device, with an effective retention time of 1-3 hours.

[0032] The evaporation unit adopts a triple-effect evaporation system 8 and is connected to the pretreatment unit. It is used to evaporate the pretreated high-salt and highly polluted wastewater and return the mother liquor to the pretreatment unit. The resulting crystals are packaged and transported off-site. An intermediate water tank 7 connects the evaporation unit and the pretreatment unit. Before the wastewater enters the triple-effect evaporation system 8, the pH value needs to be adjusted to 5-8 in the intermediate water tank 7 to reduce the amount of alkaline volatile substances entering the condensate during the evaporation process.

[0033] The condensate treatment unit is connected to the pretreatment unit and is used to treat the evaporated condensate and discharge the qualified wastewater.

[0034] It includes an anaerobic tank 10, which is connected to a primary A / O tank 11. The primary A / O tank 11 is connected to an intermediate sedimentation tank 12, which is connected to a secondary A / O tank 13. Both the primary A / O tank 11 and the secondary A / O tank 13 are equipped with nitrification liquor reflux devices to return the effluent from the O tank to the upstream A tank. The secondary A / O tank 13 is connected to a secondary sedimentation tank 14, which is connected to a discharge pipe. A secondary ozone catalytic oxidation reactor 9 is located between the anaerobic tank 10 and the triple-effect evaporation system 8. Of course, in other embodiments, for example... If the content of toxic substances in the evaporative condensate is low, the secondary ozone catalytic oxidation reactor 9 can be set between the intermediate sedimentation tank 12 and the secondary A / O tank 13; both the primary ozone catalytic oxidation reactor 3 and the secondary ozone catalytic oxidation reactor 9 are filled with a high-efficiency spherical ozone oxidation catalyst, which can be the high-efficiency spherical ozone oxidation catalyst disclosed in Chinese Patent ZL201410186473.5, and is equipped with a high-efficiency dosing device, a water distribution device, a gas distribution device and a backwashing device, with an effective residence time of 2-5 hours;

[0035] The sludge disposal unit is connected to the pretreatment unit and the condensate disposal unit respectively. It is used to dispose of the sludge generated during the treatment process and return the supernatant and filtrate generated to the pretreatment unit.

[0036] It includes a sludge thickening tank 15, which is connected to the sludge discharge pipes of the pretreatment unit and the condensate disposal unit respectively. The sludge thickening tank 15 is connected to a filter press 16. Both the sludge thickening tank 15 and the filter press 16 are connected to the pretreatment unit for returning the generated supernatant and filtrate to the pretreatment unit.

[0037] In one implementation, the pretreatment unit, evaporation unit, condensate disposal unit, and sludge disposal unit are all connected to a blower for stirring, aeration, or backwashing.

[0038] It should be understood that all connections mentioned in this embodiment are pipe connections. In practice, a booster pump can be installed on the pipe or gravity flow can be used directly, depending on the actual situation. The above connection methods are all conventional implementation schemes for those skilled in the art, and therefore will not be described in detail in this embodiment.

[0039] The method for treating high-salinity and high-pollution wastewater using the high-salinity and high-pollution wastewater treatment system provided in this embodiment includes the following steps:

[0040] S1. After being homogenized in the equalization tank, the wastewater is pumped into the air flotation device to remove most of the suspended solids and oils in the wastewater.

[0041] S2. After being treated by air flotation, the wastewater enters the first-stage ozone catalytic oxidation reactor and reacts for 3 hours. Under the action of the catalyst, ozone generates a large number of hydroxyl radicals, which oxidize the organic pollutants in the wastewater and reduce the COD and organic nitrogen concentration in the wastewater.

[0042] S3. After ozone catalytic oxidation treatment, the wastewater enters the pH adjustment tank. The pH is adjusted to about 6.3 by adding acid. Then, it is fed into the FCD three-dimensional electrolysis reactor for 2 hours. The reaction process integrates oxidation-reduction, flocculation and adsorption, catalytic oxidation and deposition. Ultimately, toxic, long-chain and cyclic heteroatom organic compounds gain electrons and undergo degradation reactions such as ring opening and chain breaking. The functional groups of toxic organic compounds are destroyed, the toxicity of microorganisms disappears, and a portion is eventually degraded into CO2 and H2O.

[0043] After the S4 and FCD three-dimensional electrolysis reaction tanks, the wastewater enters the neutralization flocculation sedimentation tank. By adding alkaline solution, coagulation and flocculant, the pH value of the wastewater is adjusted to near neutral. At the same time, the pollutants generated by the electrolysis reaction form precipitates and are separated.

[0044] S5. The effluent from the neutralization flocculation sedimentation tank flows by gravity into the intermediate water tank. Appropriate acid is added to the intermediate water tank to adjust the pH of the wastewater to about 6.0.

[0045] S6. After the above pretreatment, the wastewater is pumped into the triple-effect evaporation system for evaporation and desalination. The crystalline salt produced by evaporation is packaged and transported off-site for disposal. The mother liquor of evaporation is returned to the equalization tank and mixed with the raw water for further treatment. The condensate enters the biological system for further treatment.

[0046] S7. Before entering the biochemical treatment, the condensate is pretreated in a two-stage ozone catalytic oxidation reactor to further remove toxic pollutants and recalcitrant substances from the condensate wastewater.

[0047] S7. After secondary ozone oxidation treatment, the wastewater enters the anaerobic reactor, where most of the COD in the wastewater is removed through hydrolysis-acidification-methanation.

[0048] S8. Anaerobic effluent enters the secondary AO system. Each AO effluent stage is equipped with a separate sedimentation tank for sludge return and discharge. Under the combined action of facultative anaerobic microorganisms and aerobic bacteria in the anoxic tank, ammonia nitrogen and total nitrogen in the water are fully purified and treated, and organic matter is decomposed into CO2 and H2O, ultimately achieving stable effluent discharge that meets standards.

[0049] The pollutant removal efficiency of each unit during actual operation is shown in the table below:

[0050]

[0051]

[0052] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of ​​this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A system for treating high salinity and high pollution wastewater, characterized in that: The application relates to a high-salt and high-pollution wastewater treatment device. The device comprises a pretreatment unit for pretreating high-salt and high-pollution wastewater; an evaporation unit connected with the pretreatment unit and used for evaporating the pretreated high-salt and high-pollution wastewater and returning evaporation mother liquor to the pretreatment unit; a condensate treatment unit connected with the pretreatment unit and used for treating the evaporated condensate and discharging qualified wastewater; and a sludge treatment unit connected with the pretreatment unit and the condensate treatment unit respectively and used for treating sludge generated in the treatment process and returning supernatant and filter liquor generated to the pretreatment unit. The pretreatment unit, the evaporation unit, the condensate treatment unit and the sludge treatment unit are all connected with air blowing devices for stirring, aeration or backwashing. The pretreatment unit comprises an adjusting tank connected with a raw water pipeline and connected with a flotation device through a lifting pump, the flotation device is connected with a first-stage ozone catalytic oxidation reactor, the first-stage ozone catalytic oxidation reactor is connected with a pH adjusting tank, the pH adjusting tank is connected with an FCD three-dimensional electrolysis reaction tank, and the FCD three-dimensional electrolysis reaction tank is connected with a neutralization flocculation reaction and precipitation tank. The flotation device and the neutralization flocculation reaction and precipitation tank are both provided with dosing devices and connected with the sludge treatment unit.

2. The high salinity and high contaminant wastewater treatment system of claim 1, wherein: The FCD three-dimensional electrolysis reaction tank is filled with iron-carbon micro-electrolysis materials with high catalytic activity and is provided with water distribution devices, air distribution devices and backwashing devices.

3. The high salinity and high contaminant wastewater treatment system of claim 1, wherein: The evaporation unit is connected with the pretreatment unit through an intermediate tank.

4. The high salinity, high contamination wastewater treatment system of claim 3, wherein: The condensate treatment unit comprises an anaerobic tank connected with a first-stage A / O tank, the first-stage A / O tank is connected with an intermediate sedimentation tank, the intermediate sedimentation tank is connected with a second-stage A / O tank, the first-stage A / O tank and the second-stage A / O tank are both provided with nitrification liquid return devices, the second-stage A / O tank is connected with a secondary sedimentation tank, and the secondary sedimentation tank is connected with a discharge pipeline.

5. The high salinity, high contamination wastewater treatment system of claim 3, wherein: A second-stage ozone catalytic oxidation reactor is arranged between the anaerobic tank and the evaporation unit or between the intermediate sedimentation tank and the second-stage A / O tank.

6. The high salinity, high contamination wastewater treatment system of claim 3, wherein: The first-stage ozone catalytic oxidation reactor and the second-stage ozone catalytic oxidation reactor are both filled with high-efficiency spherical particle ozone oxidation catalysts and are provided with high-efficiency dosing devices, water distribution devices, air distribution devices and backwashing devices.

7. The high salinity and high contaminant wastewater treatment system of claim 3, wherein: The sludge treatment unit comprises a sludge concentration tank connected with sludge discharge pipelines of the pretreatment unit and the condensate treatment unit respectively, the sludge concentration tank is connected with a filter press, and the sludge concentration tank and the filter press are both connected with the pretreatment unit and used for returning supernatant and filter liquor generated to the pretreatment unit.

8. The high salinity, high contamination wastewater treatment system of claim 7, wherein: ​ 9. The high salinity, high contamination wastewater treatment system of claim 8, wherein: ​ 10. The high salinity and high contaminant wastewater treatment system of claim 1, wherein: ​

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