Coal conversion wastewater treatment system and method

Abstract

The application provides a coal chemical wastewater treatment system and a treatment method. The coal chemical wastewater treatment system comprises a pretreatment module, a first electrochemical precipitator, a hydrolysis acidification reactor, a nitrification-denitrification integrated reactor and a desalination module connected in sequence; the pretreatment module is used for removing oil impurities and solid impurities in wastewater; the hydrolysis acidification reactor is used for hydrolyzing first type molecular organic matters in wastewater into second type molecular organic matters, the diameter of the first type molecular organic matters being larger than that of the second type molecular organic matters; the nitrification-denitrification integrated reactor is used for removing part of COD in wastewater and performing denitrification treatment on the wastewater; and the desalination module is used for performing desalination treatment on the wastewater. The coal chemical wastewater treatment system can improve controllability and pertinence in the wastewater treatment process, greatly improve the volume load, reduce energy consumption, save land occupation, and has superior effluent indexes.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wastewater treatment, in particular to a device coal chemical wastewater treatment system and treatment method. BACKGROUND

[0002] Coal chemical wastewater pollutants are various in types and complex in composition, and have the following characteristics: 1. The water quantity is relatively stable, and the water quality varies according to the coal quality, product type and production process, especially the water quality varies greatly due to different production processes such as coal coking, coal gasification and coal liquefaction. 2. There are more than 300 kinds of organic matters in the wastewater, and the easily degradable organic matters mainly include phenols and benzene, such as pyrrole, naphthalene, furan and imidazole; the difficult-to-degrade organic matters include pyridine, isoquinoline, quinoline, carbazole and biphenyl. The coal chemical wastewater often contains various color-forming groups and color-developing groups, and thus has high colority and turbidity. The ratio of BOD5 to COD is lower than 0.3, and the wastewater has poor biodegradability. 3. The inorganic matters with high concentration include NH3-N, S2O3 2- , CN - , SCN - , S 2- , Cl - , which affect the biological treatment effect. 4. The wastewater has high toxicity, and the phenols, NH3-N, CN - , SCN - , S 2- have strong toxic effects on microorganisms, and the pretreatment must be comprehensively considered.

[0003] At present, the technologies for treating coal chemical wastewater at home and abroad mainly adopt traditional biochemical methods such as AAO and SBR, as well as emerging technologies such as biological membrane and biological fluidized bed, and various biological denitrification combined processes. The biochemical method has good removal effect on phenols and benzene in the wastewater, but has poor treatment effect on quinoline, indole, pyridine, carbazole and other biphenyl and heterocyclic difficult-to-degrade organic matters, so that the CODcr, NH4 + -N and TN of the effluent water of the coal chemical industry are difficult to meet the national standard requirements. In the coal chemical wastewater treatment process in the prior art, the wastewater treatment steps are mostly carried out in a pool, but the water distribution and hydraulic conditions at different positions of the pool are different, and each pool capacity cannot be fully and effectively utilized, and cannot be controlled, and the volumetric loading is low.

[0004] Therefore, the existing device coal chemical wastewater treatment system and treatment method still need to be improved. SUMMARY

[0005] The present application provides a device coal chemical wastewater treatment system and treatment method, which designs and manufactures a single device, improves the controllability and pertinence in the wastewater treatment process, greatly improves the volumetric loading, reduces the energy consumption, saves the land occupation, and has superior effluent water indicators.

[0006] The application provides a device-based coal chemical wastewater treatment system, which comprises a pretreatment module, a first electrochemical precipitator, a hydrolysis acidification reactor, a nitrification-denitrification integrated reactor and a desalination module connected in sequence.

[0007] The pretreatment module is used for removing oil impurities and solid impurities in the wastewater.

[0008] The first electrochemical precipitator is used for removing at least one of volatile phenol, SCN - , CN － , S 2- , F － , heterocyclic, polycyclic aromatic hydrocarbon COD, oil and colority in the wastewater.

[0009] The hydrolysis acidification reactor is used for hydrolyzing first-type molecular organic matters in the wastewater into second-type molecular organic matters, the first-type molecular organic matters having a larger diameter than the second-type molecular organic matters.

[0010] The nitrification-denitrification integrated reactor is used for removing part of COD in the wastewater and performing denitrification treatment on the wastewater.

[0011] The desalination module is used for performing desalination treatment on the wastewater.

[0012] According to the device-based coal chemical wastewater treatment system provided by the application, the first electrochemical precipitator comprises:

[0013] An electrochemical reaction tank, a water inlet assembly, an electrode assembly and a water collection assembly are sequentially arranged in a tank body of the electrochemical reaction tank, the electrode assembly is arranged in multiple groups and is distributed between the water inlet assembly and the water collection assembly, the electrode assembly comprises an anode and a cathode, the anode comprises first anode filler, the first anode filler comprises at least one of γ-OOFe, FeO, FeCO3, Al, VO, CuO and a complexing agent, the first anode filler further comprises protocatechuic acid and hydrothermal carbon, the cathode comprises a carbon nano-RVC blowing fluidized electrode, and the water collection assembly is used for collecting wastewater after electrochemical reaction.

[0014] A flocculation and precipitation tank, a flocculation reaction unit, a first precipitation unit and a first drainage unit are sequentially and communicatively arranged in a tank body, the flocculation reaction unit is communicated with the water collection assembly, the flocculation reaction unit is used for adding a coagulant aid to generate a flocculation reaction, and the precipitation unit is used for precipitating and separating the wastewater after the flocculation reaction.

[0015] A sludge discharge assembly is arranged at the bottom of the electrochemical reaction tank and the flocculation and precipitation tank respectively and is used for discharging sludge in the wastewater.

[0016] The device coal chemical wastewater treatment system provided by the application, the hydrolysis acidification reactor comprises:

[0017] The first main tank body is sequentially provided from bottom to top as a first water inlet unit, a hydrolysis acidification zone, a second sedimentation unit and a second water outlet unit, the hydrolysis acidification zone contains microorganisms to perform hydrolysis acidification reaction on wastewater, and the sedimentation unit is used for performing sedimentation separation on the wastewater after the hydrolysis acidification reaction;

[0018] The dissolved oxygen adjusting unit comprises a second water inlet pipe and a first water outlet pipe, the second water inlet pipe is communicated with the hydrolysis acidification zone, the first water outlet pipe is communicated with the first water inlet unit, and the dissolved oxygen adjusting unit is used for adjusting the oxygen content in the wastewater;

[0019] The first control valve is arranged on the first water outlet pipe and used for controlling the flow of the first water outlet pipe;

[0020] The sludge discharge unit is arranged at the bottom of the first main tank body and used for discharging sludge in the wastewater.

[0021] The device coal chemical wastewater treatment system provided by the application, the nitrification-denitrification integrated reactor comprises:

[0022] The second main tank body is sequentially provided from bottom to top as a second water inlet unit, an anaerobic zone, an aerobic zone, an anoxic zone and a third water outlet unit;

[0023] The anaerobic zone contains microorganisms to perform ammonification reaction on wastewater, an aeration assembly is arranged between the anaerobic zone and the aerobic zone, the aeration assembly performs aeration on the aerobic zone, the aerobic zone contains nitrifying bacteria fillers to perform nitrification reaction on the wastewater after the ammonification reaction, the anoxic zone contains denitrifying bacteria fillers to perform denitrification reaction on the wastewater after the nitrification reaction, a filter plate is arranged between the aerobic zone and the anoxic zone, the filter plate is used for filtering the wastewater flowing from the aerobic zone to the anoxic zone to block the flow of the fillers in the aerobic zone and the anoxic zone, a third sedimentation unit is separated at the center position of the anoxic zone, the third sedimentation unit is used for performing sedimentation separation on the wastewater after the denitrification reaction, and the third water outlet unit is used for discharging the wastewater after the sedimentation separation;

[0024] The reflux unit comprises a water inlet end and a water outlet end, the water inlet end is communicated with the anoxic zone, the water outlet end is communicated with the second water inlet unit, and the reflux unit is used for refluxing the wastewater in the anoxic zone to the second water inlet unit;

[0025] The second control valve is located at the outlet of the reflux unit and is used to control the water output of the reflux unit.

[0026] According to the modular coal chemical wastewater treatment system provided by the present invention, a second electrochemical precipitator is provided between the nitrification-denitrification integrated reactor and the desalination module. The second electrochemical precipitator is used to reduce the hardness of the wastewater and remove heavy metal impurities and / or residual COD from the wastewater.

[0027] According to the modular coal chemical wastewater treatment system provided by the present invention, a precipitation device and a filtration device are sequentially provided between the desalination module and the second electrochemical precipitator.

[0028] The equipment-based coal chemical wastewater treatment system provided by the present invention further includes a first sludge thickening and dewatering module and a second sludge thickening and dewatering module. The first sludge thickening and dewatering module includes a first sludge thickening tank and a first sludge dewatering tank connected in sequence, and the second sludge thickening and dewatering module includes a second sludge thickening tank and a second sludge dewatering tank connected in sequence.

[0029] The first electrochemical precipitator, the hydrolysis acidification reactor, and the nitrification-denitrification integrated reactor are respectively connected to the first sludge thickening tank, and the sedimentation device is connected to the second sludge thickening tank.

[0030] According to the modular coal chemical wastewater treatment system provided by the present invention, the desalination module includes a primary RO device, an NF device, a secondary RO device, and a bipolar membrane electrodialysis device connected in sequence.

[0031] The present invention also provides an equipment-based method for treating coal chemical wastewater, comprising:

[0032] Wastewater is pretreated to remove oil and solid impurities, resulting in wastewater A.

[0033] The wastewater A is passed into a first electrochemical precipitator for treatment to remove volatile phenols and SCN from the wastewater A. - CN － S 2- F － The COD, oil content, and color of heterocyclic and polycyclic aromatic hydrocarbons were analyzed to obtain wastewater B.

[0034] Wastewater B is passed into a hydrolysis acidification reactor for treatment, where the first type of organic molecules in wastewater B are hydrolyzed into the second type of organic molecules to obtain wastewater C. The diameter of the first type of organic molecules is larger than that of the second type of organic molecules.

[0035] The wastewater C is introduced into a nitrification-denitrification integrated reactor for treatment, part of COD in the wastewater C is removed, and the wastewater C is subjected to denitrification treatment, to obtain wastewater D;

[0036] The wastewater D is introduced into a second electrochemical precipitator for treatment, to remove hardness, heavy metal impurities and residual COD of the wastewater D, to obtain wastewater E;

[0037] The wastewater E is subjected to desalination treatment.

[0038] According to the coal chemical wastewater treatment method provided by the application, the desalination treatment comprises:

[0039] The wastewater E is introduced into a first RO device, an NF device, a first RO device and a bipolar membrane electrodialysis device in sequence for treatment.

[0040] According to the coal chemical wastewater treatment method provided by the application, after the wastewater is introduced into the NF device for reaction, the wastewater containing sulfate is introduced into a sulfate-reducing bacteria (SRB) digestion reactor and the second electrochemical precipitator in sequence for treatment.

[0041] The coal chemical wastewater treatment system and method provided by the application can improve controllability and pertinence in the wastewater treatment process, and greatly improve the volume load, by using a first electrochemical precipitator, a hydrolysis acidification reactor, a nitrification-denitrification integrated reactor and a second electrochemical precipitator to treat wastewater. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort.

[0043] Figure 1 is a schematic diagram of an embodiment of the coal chemical wastewater treatment system provided by the application;

[0044] Figure 2 is a schematic diagram of a first electrochemical precipitator in the coal chemical wastewater treatment system provided by the application;

[0045] Figure 3 is a schematic diagram of the internal structure of an electrochemical reaction tank of the first electrochemical precipitator in the coal chemical wastewater treatment system provided by the application;

[0046] Figure 4is the front view of the flocculation sedimentation tank of the first electrochemical precipitator in the coal chemical wastewater treatment system provided by the application;

[0047] Figure 5 is the internal structure schematic diagram of the flocculation sedimentation tank of the first electrochemical precipitator in the coal chemical wastewater treatment system provided by the application;

[0048] Figure 6 is the structure schematic diagram of the electrode assembly of the first electrochemical precipitator in the coal chemical wastewater treatment system provided by the application;

[0049] Figure 7 is the structure schematic diagram of the drainage unit of the first electrochemical precipitator in the coal chemical wastewater treatment system provided by the application;

[0050] Figure 8 is the wastewater treatment flow schematic diagram of the first electrochemical precipitator in the coal chemical wastewater treatment system provided by the application;

[0051] Figure 9 is the internal structure schematic diagram of the hydrolysis acidification reactor in the coal chemical wastewater treatment system provided by the application;

[0052] Figure 10 is the internal structure schematic diagram of the dissolved oxygen adjusting unit of the hydrolysis acidification reactor in the coal chemical wastewater treatment system provided by the application;

[0053] Figure 11 is the top view of the water inlet pipe of the hydrolysis acidification reactor in the coal chemical wastewater treatment system provided by the application;

[0054] Figure 12 is the top view of the water inlet unit of the hydrolysis acidification reactor in the coal chemical wastewater treatment system provided by the application;

[0055] Figure 13 is the wastewater treatment flow schematic diagram of the hydrolysis acidification reactor in the coal chemical wastewater treatment system provided by the application;

[0056] Figure 14 is the whole schematic diagram of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the application;

[0057] Figure 15 is the cross-sectional view of the reflux unit of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the application;

[0058] Figure 16 is the cross-sectional view of the water inlet unit of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the application;

[0059] Figure 17 is a schematic diagram of the aeration assembly structure of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the present application;

[0060] Figure 18 is another schematic diagram of the aeration assembly structure of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the present application;

[0061] Figure 19 is a filter plate cross-sectional view of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the present application;

[0062] Figure 20 is a schematic diagram of the three-phase separation structure of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the present application;

[0063] Figure 21 is a schematic diagram of the backwashing assembly of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the present application;

[0064] Figure 22 is a schematic diagram of the gas outlet of the backwashing assembly of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the present application;

[0065] Figure 23 is a schematic diagram of the DO gradient generated in the microbial floc of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the present application;

[0066] Figure 24 is a schematic diagram of the domestication and screening process of the short-range nitrification functional bacteria of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the present application.

[0067] Figure 25 is a schematic diagram of the generation of sulfide by the heterotrophic action of the anaerobic zone sulfate-reducing bacteria of the nitrification-denitrification integrated reactor in the coal chemical wastewater treatment system provided by the present application;

[0068] Figure 26 is a schematic diagram of the desalination module embodiment in the coal chemical wastewater treatment system provided by the present application;

[0069] Figure 27 is a schematic diagram of the coal chemical wastewater treatment method embodiment provided by the present application;

[0070] Figure 28 is a schematic diagram of the desalination module embodiment in the coal chemical wastewater treatment method provided by the present application.

[0071] Reference signs:

[0072] 1. First electrochemical precipitator; 101. Electrochemical reaction tank; 1011. Water inlet assembly; 1012. Electrode assembly; 1013. Water outlet assembly; 1014. Anode plate; 1015. Cathode; 1016. First partition plate; 1017. Pipeline assembly; 102. Flocculation and precipitation tank; 1021. Flocculation reaction unit; 1022. First precipitation unit; 1023. First water outlet unit; 1024. Second partition plate; 1025. Baffle plate; 1026. First water inlet pipe; 1027. First inclined pipe; 1028. Water outlet main pipe; 1029. Water outlet branch pipe; 103. Sludge discharge assembly; 1031. First sludge discharge pipeline; 1032. Jet sludge discharger; 104. Slag scraper;

[0073] 2. Hydrolytic acidification reactor; 201. First main tank body; 2011. First water inlet unit; 2012. Hydrolytic acidification zone; 2013. Second precipitation unit; 2014. Second water outlet unit; 2015. Annular main pipe; 2016. Annular branch pipe; 2017. Funnel box body; 2018. Second inclined pipe; 2019. Funnel sludge discharge pipeline; 2020. First water outlet pipe; 2021. Second water inlet pipe; 2022. First water outlet pipe; 2023. First box body; 2024. First baffle plate; 2025. First exhaust valve; 2026. Branch water inlet pipe; 203. First control valve; 204. Sludge discharge unit; 205. Middle sludge discharge pipeline; 206. Sampling port;

[0074] 3. Nitration-denitrification integrated reactor; 301. Second main tank body; 3011. Second water inlet unit; 30111. Main pipe; 30112. Branch pipe; 30113. Vertical short pipe; 30114. Sprayer; 3012. Anaerobic zone; 3013. Aerobic zone; 3014. Anoxic zone; 3015. Third water outlet unit; 30151. Second water outlet pipe; 3016. Aeration assembly; 30161. Aeration main pipe; 30162. Aeration branch pipe; 3017. Filter plate; 30171. Frame; 30172. First filter screen; 3018. Third precipitation unit; 30181. Second box body; 30182. Third inclined pipe; 30183. Second sludge discharge pipeline; 30184. First water inlet; 30185. Second water inlet; 30186. First baffle plate; 30187. Second baffle plate; 302. Backflow unit; 3021. First water tank; 3022. Third water inlet pipe; 3023. Second water outlet pipe; 303. Second control valve; 304. Backwashing assembly; 3041. Second water tank; 3042. Gas outlet; 3043. Gas outlet pipe; 3044. Second exhaust valve; 3045. Second filter screen; 3046. Second baffle plate;

[0075] 4, desalination module; 401, primary RO device; 402, NF device; 403, secondary RO device; 404, bipolar membrane electrodialysis device;

[0076] 5, second electrochemical precipitator; 6, combined oil removal tank; 7, mechanical grid; 8, emergency tank; 9, conditioning tank; 10, oil storage tank; 11, precipitation device; 12, filtration device; 13, first sludge thickening tank; 14, first sludge dewatering tank; 15, second sludge thickening tank; 16, second sludge dewatering tank. DETAILED DESCRIPTION

[0077] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0078] As shown in Figure 1 , the embodiment of the present application provides a device coal chemical wastewater treatment system, which comprises a pretreatment module, a first electrochemical precipitator 1, a hydrolysis acidification reactor 2, a nitrification-denitrification integrated reactor 3 and a desalination module 4 connected in sequence. The pretreatment module is used for removing oil impurities and solid impurities in the wastewater; the first electrochemical precipitator 1 is used for removing volatile phenol, SCN - , CN － , S 2- , F － , heterocyclic, polycyclic aromatic hydrocarbon COD, oil and color in the wastewater; the hydrolysis acidification reactor 2 is used for hydrolyzing first type of molecular organic matter in the wastewater into second type of molecular organic matter, the diameter of the first type of molecular organic matter being larger than that of the second type of molecular organic matter; the nitrification-denitrification integrated reactor 3 is used for removing part of COD in the wastewater and carrying out denitrification treatment on the wastewater; and the desalination module 4 is used for carrying out desalination treatment on the wastewater.

[0079] The pretreatment module, the first electrochemical precipitator 1, the hydrolysis acidification reactor 2, the nitrification-denitrification integrated reactor 3 and the desalination module 4 in the device coal chemical wastewater treatment system provided by the present application will be described in detail below, please refer to Figures 1-23 .

[0080] Pretreatment module

[0081] As shown in Figure 1As shown in this embodiment of the invention, the pretreatment module includes a combined oil removal tank 6 for oil removal and a mechanical bar screen 7 for removing solid impurities. An emergency tank 8 and a regulating tank 9 are sequentially arranged between the combined oil removal tank 6 and the first electrochemical precipitator 1. The mechanical bar screen 7 is connected to the regulating tank 9. Production wastewater can be fed into the combined oil removal tank 6 for oil removal treatment. The collected oil is temporarily stored in an oil storage tank 10 and eventually transported off-site for disposal. Domestic wastewater and floor washing water, etc., can have larger solid impurities removed by the mechanical bar screen 7 before entering the regulating tank 9 and entering the same wastewater treatment system as the production wastewater for further treatment.

[0082] First electrochemical precipitator

[0083] like Figures 2-8 As shown, in this embodiment of the invention, the first electrochemical precipitator 1 includes an electrochemical reaction tank 101 and a flocculation sedimentation tank 102. The electrochemical reaction tank 101 is sequentially provided with an inlet component 1011, an electrode component 1012, and a water collection component 1013. The electrode components 1012 are configured in multiple groups and distributed between the inlet component 1011 and the water collection component 1013. The wastewater to be treated enters the electrochemical reaction tank 101 through the inlet component 1011, flows through the electrode component 1012 to carry out an electrochemical reaction, and the wastewater after the electrochemical reaction is collected by the water collection component 1013 for further treatment.

[0084] The flocculation sedimentation tank 102 is connected in sequence to the flocculation reaction unit 1021, the first sedimentation unit 1022, and the first drainage unit 1023. The flocculation reaction unit 1021 is connected to the water collection component 1013. The wastewater after the electrochemical reaction is collected by the water collection component 1013 and then enters the flocculation reaction unit 1021 for flocculation reaction. During the process, a coagulant aid can be added as needed to promote the flocculation reaction. Finally, the first sedimentation unit 1022 separates the wastewater after the flocculation reaction. The sludge discharge component 103 is set at the bottom of the electrochemical reaction tank 101 and the flocculation sedimentation tank 102 respectively, and discharges the sludge in the wastewater at any time during the wastewater treatment process.

[0085] In this embodiment of the invention, the electrochemical reaction tank 101 and the flocculation sedimentation tank 102 are combined into an integrated device, which combines the removal of heavy metal ions, the oxidative decomposition of organic matter and flocculation sedimentation for treatment. The oxidation-reduction decomposition, electrode adsorption and flocculation sedimentation reactions in the tank are combined, which simplifies the process, achieves the effect of simultaneous removal and enhances the separation effect.

[0086] The water inlet assembly 1011, the electrode assembly 1012 and the water collecting assembly 1013 are sequentially arranged in the electrochemical reaction tank 101, the flocculation and precipitation tank 102 is sequentially connected with the flocculation reaction unit 1021, the first precipitation unit 1022 and the first water discharge unit 1023, and in the treatment process of the wastewater, electricity is used instead of adding various reagents, the water body does not introduce or introduces as few as possible other substances, secondary pollution is avoided, and only the voltage, the current and the frequency of the power supply are controlled in the treatment process, without complicated reagent adding and detection means, so that the application is relatively wide.

[0087] As shown in Figure 6 The electrode assembly 1012 in some embodiments of the present application includes the anode plate 1014 and the cathode 1015, the structure of the anode plate 1014 is a trapezoidal bending structure with opposite directions, a plurality of water outlet holes are uniformly distributed on the anode plate 1014, the wastewater to be treated flows through the anode plate 1014 to perform electrochemical reaction through the water outlet holes, the cathode 1015 is a tubular structure, the cathode 1015 is arranged in the trapezoidal bending structure and maintains a set distance from three surfaces of the trapezoidal bending structure. The trapezoidal bending structure of the anode plate 1014 is beneficial to improve the efficiency of the electrode discharge, and the cathode 1015 is arranged in the trapezoidal bending structure of the anode plate 1014 to form a combined electrode structure, to ensure the generation of in-situ ferrous ions and double-electron oxygen reduction reaction, increase the generation of oxidized substance free hydroxyl, ensure the efficient performance of the electrode oxidation reaction Fenton chemical reaction, improve the formation of precipitates, and thus enhance the separation effect. Specifically, in some embodiments of the present application, the first anode filler is arranged in the anode plate 1014, the first anode filler includes at least one of γ-OOF e, FeO, FeCO3, Al, VO, CuO and a complexing agent, the first anode filler further includes protocatechuic acid and hydrothermal carbon, and the first anode filler is mainly steel smelting associated material or furnace charge waste material; the cathode includes a carbon nano-RVC injection fluidized electrode.

[0088] The electrochemical treatment process of the first electrochemical precipitator 1 will be described below.

[0089] The first anode filler: a three-dimensional filler combined electrode formed by γ-OOFe, FeO, FeCO3, Al, VO, CuO, a complexing agent (one or more), protocatechuic acid and hydrothermal carbon, and the main filler is steel smelting associated material or furnace charge waste material.

[0090] The cathode: a carbon nano-RVC injection fluidized electrode, injection air / O2 double-electron reaction·OH rich catalysis, oxidation rate is increased by 10000 times.

[0091] The power supply: a special power supply: a square wave multi-pulse power supply, energy saving 65-85%, efficiency increased by 3 times.

[0092] Cyclic output ten groups of different parameters of current waveform, each group of current can be in direct current, single pulse, double pulse or direct current commutation waveform arbitrarily selected.

[0093] The duration of each group of current can be selected between 1S-9999S, facilitating the control of each group of current.

[0094] In the alternating operation process of each group of pulse current, the average current is always constant, so as to ensure that the peak value of each group of pulse is different when different duty cycles are used.

[0095] Pulse frequency: 5-5000Hz

[0096] Pulse duty cycle: 0-100%

[0097] Positive and negative pulse commutation time: 0-9999ms

[0098] The duration of each group of current: t1>=1S, t2-t 10 <=9999S

[0099] Output voltage: 0-100V

[0100] Output maximum average current: 0-5000A

[0101] Maximum peak current: 30A-15000A

[0102] The electrochemical precipitator provided by the application has the following advantages:

[0103] 1) The principle of electro-Fenton reaction can realize in-situ production of H2O2, and only a small amount of chemical reagent needs to be added, and the required H2O2 and Fe 2+ Can be generated in-situ, greatly reducing the treatment cost, and effectively avoiding the risk of reagent transportation, storage or treatment;

[0104] 2) The electrode oxidation and self-produced Fenton reagent oxidation reaction is complete, and no secondary pollution is produced;

[0105] 3) The treatment equipment is relatively simple, and the main parameters of the electrochemical operation process are current or voltage, which is easy to realize automatic program control;

[0106] 4) The electro-Fenton method can continuously and effectively degrade organic matter in wastewater for a long time, and Fe 2+ And H2O2 in the solution are continuously generated at a certain rate, and the degradation of organic matter is more complete;

[0107] 5) Fe 2+Cathode regeneration and recycling, according to the need for filler electrode rich in hydrothermal carbon or PCA, EDTA complexing agent, will not produce pollution by Fe(OH)3 sludge, reduce the production of iron mud, almost no secondary pollution, simple post-processing;

[0108] 6) More degradation factors make the treatment efficiency of electro-Fenton method higher than that of traditional Fenton method, these factors include: anodic oxidation, oxidation of hydroxyl radicals and electric adsorption, etc.;

[0109] 7) Electrochemistry can be directly combined with high-density precipitation process, and the process is flexible;

[0110] 8) Small footprint, short processing cycle and low operating cost; The footprint is one-fifth of the original treatment process (cyanide breaking process, air flotation process, primary strong aeration process, primary sedimentation tank process), and the treatment process only consumes electricity. Electrochemical power supply is low-voltage direct-current pulse power supply, and the power supply only forms a micro-current on the electrode surface. Due to the special structure and material, the polarization reaction is avoided, and the power consumption is one-tenth of the traditional process.

[0111] Mechanism: electro-Fenton principle, three-dimensional filler anode changes iron elements in the filler into Fe 2+ by electrolysis, and the combined cathode generates H2O2 by two-electron reduction reaction of O2 through aeration first at the cathode, and the generated H2O2 can rapidly react with Fe 2+ oxidized by the anode filler to generate ·OH and Fe 3+ , and the strong oxidation ability of ·OH is used to achieve the purpose of removing refractory organic matter, and the complexed Fe 3+ in the filler does not participate in the precipitation reaction and is reduced to Fe 2 at the cathode. + Thus, the oxidation reaction is recycled.

[0112] Cathode oxidation and reduction mainly includes two ways:

[0113] 1) Oxygen loses two electrons at the cathode and is reduced to H2O2:

[0114] O2+2H + +2e - —H2O2

[0115] The generated H2O2 continues to react to generate H2O:

[0116] H2O2+2H + +2e - —H2O

[0117] 2) Direct reduction of oxygen by four electrons to generate H2O:

[0118]

[0119] According to the above reaction mechanism, the oxygen in the electrode system is reduced to H2O2 at the cathode mainly in two steps:

[0120] 1) The dissolved oxygen in the solution gathers at the cathode, and in the process of diffusion to the cathode surface, it is adsorbed on the surface of the cathode,

[0121] 2) The dissolved oxygen is reduced to H2O2 at the cathode through a two-electron reduction pathway, which is the main process of the cathodic redox to H2O2 in the electro-Fenton system.

[0122] During the experiment, the appropriate cathode electrode was sought in order to obtain a higher H2O2 yield, and the criteria were:

[0123] A. To increase the mass transfer effect of oxygen to the electrode surface to select the appropriate electrode material;

[0124] B. The selected cathode electrode material should have good catalytic activity for oxygen reduction reaction, and shorten the reaction time;

[0125] C. In the process of redox reaction, the cathode needs to inhibit the four-electron reduction of oxygen, and also needs to hinder the two-electron reduction of H2O2.

[0126] The above factors need to be considered first in the process of selecting the cathode material, in order to find the most suitable cathode material to improve the H2O2 yield. The combined cathode electrode improves the efficiency and the concentration of the strong oxidizing agent H2O2 by aeration and oxygenation to the electrode surface of the reticular vitreous carbon (RVC). Reticular vitreous carbon is a three-dimensional reticular microporous material composed of vitreous foam, with a porosity of 90%-97%, a small density (0.03 g / cm 3 ), high chemical stability, specific surface area and electrical conductivity, low thermal conductivity and thermal expansion coefficient, and high structural strength, small resistance to fluid.

[0127] The removal of pollutants by electrochemistry is mainly through oxidation and coagulation of organic matter. Oxidation oxidizes organic matter in water to CO2, H2O and small molecules, achieving the effect of degrading harmful substances in water. Coagulation relies on the flocculation and adsorption of Fe(OH) n colloid generated by the reaction to remove part of the organic pollutants in the water.

[0128] SCN - is removed:

[0129] SCN - → SCN + e -

[0130] SCN - + SCN . → (SCN)2 -

[0131] SCN - + (SCN)2 - → (SCN)3 - is reduced

[0132] SCN - → S sds + CN -

[0133] S sds + 4H2O → SO4 2- + 8H + + 6e -

[0134] CN - is removed:

[0135] Electrode oxidation reaction: CN - + 2OH - - 2e - → CNO + H2O

[0136] CN - + 4OH - - 6e - → 2CO2 + N2 + 2H2O

[0137] CNO + 2H2O → NH4 + + CO3 2-

[0138] Chemical complexation precipitation reaction: Fe 2+ + CN - → Fe(CN)6 4-

[0139] or Fe 3+ + CN - → Fe(CN)6 3-

[0140] Fe(CN)6 4- + Fe 3+ → Fe4(Fe(CN)6)3, Prussian blue precipitate

[0141] or Fe(CN)63- +Fe 2+ →Fe3(Fe(CN)6)2, Thunberg's blue precipitate S 2- Removal:

[0142] Electrode redox reaction S 2- +H₂O→H + +SO4 2- +·OH

[0143] Chemical complexation precipitation reaction: S 2- +Fe 2+ →FeS precipitation

[0144] Removal of recalcitrant organic matter:

[0145] Phenolic substances can be removed at a rate exceeding 90% through electrode redox reactions and addition reactions with hydroxyl radicals (·OH). Heterocyclic and polycyclic aromatic organic compounds exhibit significantly improved biodegradability through electrode redox reactions and chain-scissing reactions with hydroxyl radicals (·OH). Fe 3+ Fe is achieved by reacting with organic free radicals R· 2+ Regeneration, such as Fe 3+ +R·→Fe 2+ +R + As shown, depending on the different groups R in the organic compounds (such as -OH, -OR, ammonia nitrogen groups, etc.), the reaction kinetic constant is approximately k = 107–108 L·mol⁻¹. -1 ·s -1 However, R· also participates in the equation R·+Fe 2+ +H + →Fe 3+ The oxidation process shown in +RH is accompanied by the polymerization annihilation process R·+R·→R-R.

[0146] like Figure 3 As shown, in some embodiments of the present invention, the inlet component 1011 and the outlet component 1013 are respectively arranged on both sides of the pool body. The pool body is provided with a first partition 1016 for separating the inlet component 1011 and the outlet component 1013. The bottom of the first partition 1016 is kept at a set distance from the bottom of the pool. The arrangement of the first partition 1016 makes the flow path of the wastewater in the pool body U-shaped, which increases the reaction time of the wastewater in the pool body and allows some of the sludge in the wastewater to settle at the bottom of the pool body and be discharged by the sludge discharge component 103, which plays a preliminary sedimentation role and thus enhances the separation effect.

[0147] The water inlet assembly 1011 and the water collecting assembly 1013 are both water inlets and water outlets of the pipeline assembly 1017, and the pipeline assembly 1017 is uniformly provided with water holes; the pipeline assembly 1017 can be uniformly distributed on the pool top, and the water holes on the pipeline assembly 1017 can make the water flow in a stratified manner during water inlet and water outlet, thereby ensuring the uniformity in the wastewater treatment process and enhancing the separation effect.

[0148] As shown in FIG. 10, Figure 5 As shown in FIG. 10, the flocculation reaction unit 1021, the first sedimentation unit 1022 and the first drainage unit 1023 in some embodiments of the present application are sequentially separated by the second partition plate 1024, the bottom of the second partition plate 1024 between the flocculation reaction unit 1021 and the first sedimentation unit 1022 is kept at a set distance from the bottom of the pool, and the first sedimentation unit 1022 and the first drainage unit 1023 are communicated through the top of the second partition plate 1024. The second partition plate 1024 plays the same role as the first partition plate 1016, and thus will not be described here.

[0149] As shown in FIG. 10, Figure 5 As shown in FIG. 10, the flocculation reaction unit 1021 in some embodiments of the present application includes a plurality of folded plates 1025 with opposite inclined directions, which are sequentially and spacedly distributed from the top to the bottom of the pool body, i.e., a plurality of folded plates 1025 are fixed on one side of the pool wall of the flocculation reaction unit 1021, and a plurality of folded plates 1025 are also fixed on one side of the second partition plate 1024. The folded plates on the two sides are sequentially and spacedly crossed and inclined towards the center of the flocculation reaction unit 1021. A first water inlet pipe 1026 is arranged on the top of the flocculation reaction unit 1021, and the first water inlet pipe 1026 is communicated with the pipeline assembly 1017 of the water collecting assembly 1013. The first water inlet pipe 1026 can be provided with a dosing port (not shown in the figure), and a coagulant can be added to the first water inlet pipe 1026 according to the water quality. The wastewater treated by the electrochemical reaction enters the flocculation reaction unit 1021 through the pipeline assembly 1017 of the water collecting assembly 1013 and the first water inlet pipe 1026, and the flow path of the wastewater is S-shaped due to the spacedly and crossed arrangement of the folded plates 1025, so that the reaction time of the wastewater and the coagulant can be prolonged, more flocculation precipitates can be produced in the wastewater, and the separation effect is enhanced.

[0150] As shown in FIG. 10, Figure 5 As shown in FIG. 10, the folded plates 1025 in the flocculation reaction unit 1021 in some embodiments of the present application can also be inclined towards the direction opposite to the center of the flocculation reaction unit 1021, and the technical effects described above can still be achieved, and thus will not be described here.

[0151] The first precipitation unit 1022 in some embodiments of the present application comprises a plurality of first inclined pipes 1027 which are uniformly spaced in the upper half of the first precipitation unit 1022. The water flow after the flocculation reaction enters the first precipitation unit 1022 through the bottom of the second partition 1024, slowly rises from the bottom of the first precipitation unit 1022, and slowly flows through the first inclined pipes 1027 as the water flow rises, while the flocculation precipitates and sludge slide down along the first inclined pipes 1027, gradually achieving the precipitation separation of the wastewater after the flocculation reaction unit 1021, thereby enhancing the separation effect, and the flocculation precipitates and sludge are discharged through the sludge discharge assembly 103 arranged at the bottom of the pool.

[0152] In some embodiments of the present application, the top of the second partition 1024 between the first precipitation unit 1022 and the first drainage unit 1023 is flush with the first inclined pipes 1027, so that the water separated by the first inclined pipes 1027 enters the first drainage unit 1023 from the top of the second partition 1024.

[0153] The first drainage unit 1023 comprises a drainage main pipe 1028 and a plurality of drainage branch pipes 1029 which are horizontally arranged at the top of the first drainage unit 1023 and are respectively connected, and the plurality of drainage branch pipes 1029 are uniformly distributed with drainage holes. The drainage main pipe 1028 is connected with an external drainage pipeline. The horizontal arrangement of the drainage main pipe 1028 and the plurality of drainage branch pipes 1029 at the top of the first drainage unit 1023 can make the flow during drainage in a layered manner, ensuring the uniformity during the wastewater treatment process, thereby enhancing the separation effect.

[0154] A water level controller (not shown in the figure) can be additionally arranged at the top of the first drainage unit 1023 to ensure the cooperation of water production and drainage.

[0155] An ion air flotation generator (not shown in the figure) can be additionally arranged at the bottom of the first drainage unit 1023 to further flocculate the suspended matter in the water in the first drainage unit 1023, thereby enhancing the separation effect.

[0156] In some embodiments of the present application, a slag scraper 104 is arranged at the top of the electrochemical reaction pool 101 and the flocculation precipitation pool 102. The slag scraper 104 is used for slag scraping operation during the wastewater treatment process. The slag scraper 104 can be arranged at the middle or one side of the pool body, i.e. the slag scraper 104 can scrape slag from the middle to both sides or to one side, to ensure the normal operation of the wastewater treatment process.

[0157] According to some embodiments of the present invention, the sludge discharge assembly 103 includes a first sludge discharge pipe 1031 and a jet sludge discharger 1032. The jet sludge discharger 1032 is evenly distributed in the first sludge discharge pipe 1031. The first sludge discharge pipe 1031 is set at the bottom of the electrochemical reaction tank 101 and the flocculation sedimentation tank 102. The bottom of the electrochemical reaction tank 101 and the flocculation sedimentation tank 102 can also be set in a funnel shape to facilitate the storage and discharge of sludge in wastewater. The jet sludge discharger 1032 is a sludge discharger in the prior art, and the specific principle will not be described here.

[0158] Figure 8 The diagram illustrates the overall wastewater treatment process in some embodiments of the present invention, namely, the wastewater to be treated first enters the electrochemical reaction tank 101, and after the electrochemical reaction, it enters the flocculation sedimentation tank 102, and after the flocculation sedimentation reaction, it is discharged.

[0159] In this embodiment of the invention, the electrochemical reaction tank and the flocculation sedimentation tank are combined into an integrated device, which combines the removal of heavy metal ions, the oxidative decomposition of organic matter and flocculation sedimentation for treatment. The oxidation-reduction decomposition, electrode adsorption and flocculation sedimentation reactions that occur in the tank are combined, which simplifies the process, achieves the effect of simultaneous removal and enhances the separation effect.

[0160] The electrochemical reaction tank is equipped with an inlet assembly, an electrode assembly, and a water collection assembly in sequence. The flocculation sedimentation tank is connected in sequence to a flocculation reaction unit, a sedimentation unit, and a drainage unit. The flocculation reaction unit is connected to the water collection assembly. The flocculation reaction unit is used to add coagulant aids to induce flocculation, and the sedimentation unit is used to separate the wastewater after flocculation. In the wastewater treatment process, electricity is used instead of adding various chemicals, and other substances are introduced into the water body with little or no interference, avoiding secondary pollution. The treatment process only requires control of the voltage, current, and frequency of the power supply, eliminating the need for complicated chemical dosing and detection methods, and is widely used.

[0161] Hydrolysis acidification reactor

[0162] like Figures 9-13 As shown, in this embodiment of the invention, the hydrolysis acidification reactor 2 includes a first main tank 201, a dissolved oxygen regulating unit 202, a first control valve 203, and a sludge discharge unit 204. The first main tank 201 is configured from bottom to top as a first water inlet unit 2011, a hydrolysis acidification zone 2012, a second sedimentation unit 2013, and a second drainage unit 2014. The first water inlet unit 2011 is used to introduce the wastewater to be treated into the first main tank 201. The hydrolysis acidification zone 2012 contains microorganisms to carry out the hydrolysis acidification reaction on the wastewater. The second sedimentation unit 2013 is used to precipitate and separate the wastewater after the hydrolysis acidification reaction. The second drainage unit 2014 discharges the cleaned water.

[0163] Specifically, the dissolved oxygen adjusting unit 202 comprises a second water inlet pipe 2021 and a first water outlet pipe 2022, the second water inlet pipe 2021 is communicated with the hydrolysis acidification zone 2012, the first water outlet pipe 2022 is communicated with the first water inlet unit 2011, the dissolved oxygen adjusting unit 202 is used for adjusting the oxygen content in the wastewater, a first control valve 203 is arranged on the first water outlet pipe 2022, the wastewater to be treated enters the first main tank body 201 through the first water inlet unit 2011, slowly rises to the hydrolysis acidification zone 2012, is pumped into the dissolved oxygen adjusting unit 202 through the water inlet pipe, the oxygen content in the wastewater is adjusted, the wastewater adjusted by the dissolved oxygen adjusting unit 202 is transported back to the first water inlet unit 2011 through the first water outlet pipe 2022, and enters the first main tank body 201 together with the untreated wastewater to carry out the hydrolysis acidification reaction, and the flow of the first water outlet pipe 2022 is controlled by the first control valve 203.

[0164] In the embodiment of the present application, the dissolved oxygen adjusting unit 202 is arranged in a wastewater reflux mode, so that the timing of adjusting the oxygen content of the wastewater can be controlled at any time, and the normal hydrolysis acidification reaction is ensured, further, part of the wastewater in the first main tank body 201 is adjusted in oxygen content through the reflux mode, and then enters the hydrolysis acidification zone 2012 together with the untreated wastewater, so that the oxygen content in the hydrolysis acidification zone 2012 is controlled within the range of 0.3 mg / L-1 mg / L, and the hydrolysis acidification reaction in the first main tank body 201 is carried out under the limited oxygen condition, the activity of the acidification microorganism under the limited oxygen condition is stronger, the suspended solid substances in the wastewater are effectively converted into dissolved substances, and the macromolecular substances with biodegradability and biological toxicity inhibition are converted into small molecular substances, so that the biodegradability of the wastewater is improved.

[0165] In addition, in the embodiment of the present application, the hydrolysis acidification zone 2012 and the second sedimentation unit 2013 are combined, and the wastewater is subjected to hydrolysis acidification and then subjected to sedimentation separation in the second sedimentation unit 2013, on the one hand, the hydrolysis acidification and the sedimentation are carried out in sequence and do not interfere with each other, so that the wastewater treatment efficiency is improved, on the other hand, the space utilization rate of the tank body is increased, and the occupied area is only half of that of the traditional process, and the operation cost is low.

[0166] In some other embodiments of the present application, the bottom of the first main tank body 201 is provided with a sludge discharge unit 204. Since the bottom of the first main tank body 201 will accumulate particulate matter and small sand particles, the sludge discharge unit 204 can be configured with a jet flow sludge discharger, which uses air power to forcibly discharge sludge. In this way, the accumulation of sand particles in the first main tank body 201 can be avoided or reduced. The jet flow sludge discharger is a sludge discharger in the prior art, and the specific principle will not be described here. In addition, a sludge discharge pipeline can also be added to the second water inlet pipe 2021. A jet mixer is arranged at the interface between the sludge discharge pipeline and the second water inlet pipe 2021. The jet mixer uses negative pressure to suck the sludge in the backflow wastewater in the second water inlet pipe 2021, so as to preliminarily discharge the wastewater. The jet mixer is a sludge discharger in the prior art, and the specific principle will not be described here.

[0167] As shown in the drawings, Figure 10 The dissolved oxygen adjusting unit 202 in some embodiments of the present application includes a first box body 2023. A first baffle 2024 is arranged in the first box body 2023. The first baffle 2024 divides the first box body 2023 into a water inlet area and a water outlet area. The water inlet area and the water outlet area are communicated through the top of the first baffle 2024. The bottom of the water inlet area is connected with one end of the second water inlet pipe 2021. The other end of the second water inlet pipe 2021 is horizontally arranged in the hydrolysis acidification area 2012. The bottom of the water outlet area is connected with one end of the first water outlet pipe 2022. The other end of the first water outlet pipe 2022 is connected with the first water inlet unit 2011. A grid tile aeration filler is arranged in the water outlet area. The top of the first box body 2023 is further provided with a first exhaust valve 2025.

[0168] Specifically, the wastewater just entering the first main tank body 201 is a mixed flow containing sludge, water and gas. The mixed flow is pumped into the water inlet area in the first box body 2023 through the water inlet pipe. Due to the sludge discharge pipeline and the jet mixer added to the second water inlet pipe 2021, the mixed liquid will be aerated during the sludge discharge process, and the oxygen content in the mixed liquid will increase. The mixed flow rises to the upper space of the first box body 2023 through the first baffle 2024. Most of the gas is separated to the top of the first box body 2023 during the rising process. After passing through the first baffle 2024, the sludge-water mixed flow enters the water outlet area and flows through the grid tile aeration filler. The dissolved gas is separated into bubbles again in this part. The bubbles rise to the top. The gas at the top of the first box body 2023 is discharged through the first exhaust valve 2025. The sludge-water is returned to the first water inlet unit 2011 through the first water outlet pipe 2022. In this process, the gas in the mixed liquid can be separated and discharged through the first baffle 2024 and the grid tile aeration filler, and then mixed with the untreated wastewater. At this time, the oxygen content in the sludge-water is ensured to be within the range of 0.3-1 mg / L. The hydrolysis acidification reaction in the first main tank body 201 is carried out under the limited oxygen condition, so as to improve the biodegradability of the wastewater.

[0169] As shown in the drawings, Figure 11As shown in the drawings, the other end of the second water inlet pipe 2021 in some embodiments of the present application is also connected with multiple groups of branch water inlet pipes 2026, and multiple water suction and expansion pipes are evenly distributed on the branch water inlet pipes 2026. The shape of the water suction and expansion pipe is conical, and the large opening end is arranged towards the water surface, and the small opening end is connected with the branch water inlet pipe 2026. Multiple groups of branch water inlet pipes 2026 are evenly distributed on the cross section of the entire first main tank body 201. Water enters the branch water inlet pipe 2026 from the large opening end of the water suction and expansion pipe, so as to ensure uniform water inlet flow rate. The branch water inlet pipe 2026 can be provided as 4-6 groups, or can be increased or decreased according to the specific cross-sectional area of the first main tank body 201 and the rising flow rate of the wastewater, and the embodiments of the present application are not limited.

[0170] As shown in the drawings, Figure 9 and Figure 12 As shown in the drawings, the first water inlet unit 2011 in some embodiments of the present application includes a ring-shaped main pipe 2015, multiple groups of ring-shaped branch pipes 2016 and nozzles. The ring-shaped main pipe 2015 is coaxially arranged with the first main tank body 201 and connected with an external wastewater pipeline. Multiple groups of ring-shaped branch pipes 2016 are respectively communicated with the ring-shaped main pipe 2015 and coaxially arranged with the ring-shaped main pipe 2015. The ring-shaped branch pipes 2016 are preferably 4 groups. The 4 groups of ring-shaped branch pipes 2016 are sequentially and spacedly distributed from the bottom to the top of the tank and gradually increase in diameter in the direction of the inclined tank wall. The inclined direction formed by the sequentially distributed 4 groups of ring-shaped branch pipes 2016 has an angle of 40°-60° with the central axis direction of the first main tank body 201, and the angle is preferably 45° in the present embodiment. Multiple nozzles are also evenly distributed on the ring-shaped branch pipes 2016. The nozzles are arranged in the direction of the inclined axis and have the same angle of 45° with the central axis direction of the first main tank body 201. By arranging the ring-shaped branch pipes 2016 and the nozzles in the inclined direction, the water inlet forms a spiral rising state, which can well mix and stir the sludge and the water inlet. The uneven water distribution and short flow phenomenon can be avoided, so that the dead zone is not formed in the first main tank body 201 to cause the loss of sludge, and the sludge biomass in the first main tank body 201 can be improved, thereby enhancing the sludge and water separation effect.

[0171] In some embodiments of the present invention, the second sedimentation unit 2013 includes a funnel box 2017 and a second inclined tube 2018. The second inclined tube 2018 is disposed on the upper part of the funnel box 2017, preferably filling the entire upper part of the funnel box 2017. Multiple water inlets are provided on the bottom sidewall of the funnel box 2017, and the water inlets are evenly distributed on the bottom sidewall of the funnel box 2017. A funnel sludge discharge pipe 2019 is also provided at the bottom of the funnel box 2017, through which the water after the hydrolysis and acidification reaction flows. The water enters the funnel box 2017 through the inlet hole. As the water flows upward, it slowly flows through the second inclined tube 2018. The hydrolysis acidification reaction products and sludge slide down through the second inclined tube 2018, gradually achieving sedimentation and separation of the wastewater after the hydrolysis acidification reaction. The separated granular sludge gradually aggregates into larger sludge pieces, which fall to the bottom of the funnel box 2017 under their own weight. The sludge then flows through the funnel sludge discharge pipe 2019 located at the bottom of the funnel box 2017 and merges with the sludge discharge pipe located at the second inlet pipe 2021 for discharge. The inlet hole is preferably a small hole, allowing the mud-water mixture to pass through but preventing large sludge pieces from passing through.

[0172] In some embodiments of the present invention, the second drainage unit 2014 includes a first drainage pipe 2020 disposed on the top of the first main tank 201. The first drainage pipe 2020 can be configured as multiple sets, with water evenly distributed on the top of the first main tank 201. This allows the flow during drainage to be discharged in layers, ensuring uniformity in the wastewater treatment process and synergistic production and discharge, thereby enhancing the separation effect and ensuring the output volume.

[0173] In some embodiments of the present invention, the sludge discharge unit 204 includes a sludge discharge funnel 2041 and a bottom sludge discharge pipe 2042. The sludge discharge funnel 2041 is disposed at the bottom of the first main tank 201, and the annular main pipe 2015 is disposed on the side wall of the sludge discharge funnel 2041. The side wall of the sludge discharge funnel 2041 provides support for the annular main pipe 2015. The bottom sludge discharge pipe 2042 is connected to the bottom of the sludge discharge funnel 2041. By setting the sludge discharge funnel 2041 in a funnel shape, the sludge formed in the wastewater at the bottom can slide down the side wall of the funnel to the bottom, and then be discharged through the bottom sludge discharge pipe 2042, ensuring balanced sludge discharge during the overall reaction process.

[0174] For example Figure 9 As shown, in some embodiments of the present invention, a central sludge discharge pipe 205 is provided between the first water inlet unit 2011 and the hydrolysis acidification zone 2012. The central sludge discharge pipe 205 is used to discharge sludge from the wastewater before it enters the hydrolysis acidification zone 2012, so as to ensure balanced sludge discharge during the overall reaction process.

[0175] In some other embodiments of the present application, the first main tank body 201 is provided with a plurality of sampling ports 206 in the vertical direction for sampling wastewater at different reaction stages, observing the growth of bacterial colonies, i.e. sludge concentration, and adjusting the parameters in the reaction process in real time, thereby improving the wastewater treatment efficiency and ensuring the water output.

[0176] Figure 13 The overall process of wastewater treatment in some embodiments of the present application is shown in FIG. 1. The wastewater to be treated first enters the first main tank body 201, and gradually enters the hydrolysis acidification zone 2012 from the bottom of the first main tank body 201. Part of the wastewater is returned to the dissolved oxygen adjusting unit 202 through the second water inlet pipe 2021 for adjustment. The adjusted wastewater is mixed with untreated wastewater through the first water outlet pipe 2022 and enters the first main tank body 201. After hydrolysis acidification, the wastewater enters the second sedimentation unit 2013 for sedimentation and separation, and is then discharged through the second drainage unit 2014.

[0177] The bacterial colony treatment process of the hydrolysis acidification reactor 2 is described below.

[0178] Sulfate-reducing bacteria (SRB) are inoculated and utilized. The coal wastewater usually has a high concentration of sulfate, and part of the sulfur element is converted into sulfate during the thiocyanate pretreatment and biochemical treatment process. The sulfate-reducing bacterial colony can treat part of the COD of the nitrogen-containing organic matter, remove one part of the sulfate to generate two parts of the alkalinity required for the subsequent nitrification process, the generated thiocyanate participates in the subsequent autotrophic denitrification reaction, and finally generates elemental sulfur. Example description: 100g COD + 150.2g SO4 2- +43.7g H2O→53.2g H2S + 1.9g sludge + 190.9g HCO3 - Sulfate-type anaerobic ammonia oxidation bacteria (ASR) are inoculated and utilized, and form competition with SRB bacteria. However, the ASR bacteria have a short generation cycle, a unique biological sheath, and secrete viscous polysaccharide substances, and are the skeleton structure of the granular sludge under limited oxygen conditions (DO < 0.5mg / L).

[0179] 4NH4 + +3SO4 2- →3S ο +4NO2 - +4H2O+8H +

[0180] Fe ion type anaerobic ammonia oxidation bacteria (FEAMMOX) have the same effect as ASR.

[0181] NH4 + +6Fe(OOH)+10H + →NO2 - +6Fe 2+ +10H2O

[0182] The hydrolysis acidification reactor 2 is started in stages, first 1.8 kg SO4 2- - S / m3.d, 16 kg COD of volume load is operated for a period of time; in the second stage, 0.55 kg NO3 - - N / m3.d, the final sulfuric acid removal rate is 98%, the nitrate removal rate is 97%, the COD removal rate is 72%, and the elemental sulfur generation rate is 89%.

[0183] The upflow hydrolysis acidification treatment device provided by the application comprises a main tank body and a dissolved oxygen adjusting unit, the main tank body is sequentially arranged from bottom to top as a water inlet unit, a hydrolysis acidification zone, a sedimentation unit and a water outlet unit, the hydrolysis acidification zone contains microorganisms to perform hydrolysis acidification reaction on wastewater, and the dissolved oxygen adjusting unit is used to adjust the oxygen content in the wastewater, so that the hydrolysis acidification reaction in the main tank body is performed under a limited oxygen condition, the activity of acidification microorganisms is stronger under the limited oxygen condition, and the suspended solid substances in the wastewater are effectively converted into soluble substances, and the large molecular substances with biodegradation inhibition are converted into small molecular substances which are easy to biodegrade, so that the biodegradation performance of the wastewater is improved.

[0184] In addition, the upflow hydrolysis acidification treatment device provided by the application combines the hydrolysis acidification zone and the sedimentation unit, and the wastewater is subjected to sedimentation separation in the sedimentation unit only after hydrolysis acidification, on the one hand, the hydrolysis acidification and the sedimentation are sequentially performed without interference with each other, and the wastewater treatment efficiency is improved; on the other hand, the space utilization rate of the tank body is increased, and the occupied area is only half of that of the traditional process, and the operation cost is low.

[0185] The nitration-denitrification integrated reactor comprises a first main tank body 201, a reflux unit 202 and a first control valve 203, the first main tank body 201 is sequentially arranged from bottom to top as a first water inlet unit 2011, an anaerobic zone 2012, an aerobic zone 2013, an anoxic zone 2014 and a second water outlet unit 2015, the first water inlet unit 2011 is used to introduce the wastewater to be treated into the first main tank body 201, the anaerobic zone 2012 contains microorganisms and is used to perform hydrolysis acidification reaction and ammoniation reaction on the wastewater, an aeration assembly 2016 is arranged between the anaerobic zone 2012 and the aerobic zone 2013, and the aeration assembly 2016 performs aeration on the aerobic zone 2013.

[0186] As shown in the embodiment of the application, the nitration-denitrification integrated reactor 3 comprises a second main tank body 301, a reflux unit 302 and a second control valve 303, the second main tank body 301 is sequentially arranged from bottom to top as a second water inlet unit 3011, an anaerobic zone 3012, an aerobic zone 3013, an anoxic zone 3014 and a third water outlet unit 3015, the second water inlet unit 3011 is used to introduce the wastewater to be treated into the second main tank body 301, the anaerobic zone 3012 contains microorganisms and is used to perform hydrolysis acidification reaction and ammoniation reaction on the wastewater, an aeration assembly 3016 is arranged between the anaerobic zone 3012 and the aerobic zone 3013, and the aeration assembly 3016 performs aeration on the aerobic zone 3013. Figures 14-22

[0187] ​The aerobic zone 3013 contains nitrifying bacteria filler, which is used for nitrification reaction of the wastewater subjected to ammonification reaction. The filler in the aerobic zone 3013 is preferably filled with 30%-50% of granular filter material with a particle size of 6-8 mm and 20% of K3 filler, so that the filler in the aerobic zone 3013 has strong adsorption capacity, and the biofilm on the filler can quickly purify the wastewater, thereby improving the wastewater treatment efficiency. The anoxic zone 3014 contains denitrifying bacteria filler, which is used for denitrification reaction of the wastewater subjected to nitrification reaction. The anoxic zone 3014 is preferably filled with K3 filler, and the loading rate is ensured to be 30%-70%. The K3 filler is fused with a plurality of trace elements beneficial to the rapid attachment and growth of microorganisms in the high molecular material, thereby further improving the biological activity of the denitrifying bacteria.

[0188] The filter plate 3017 is arranged between the aerobic zone 3013 and the anoxic zone 3014, and is used for filtering the wastewater flowing from the aerobic zone 3013 to the anoxic zone 3014, so as to block the mutual flow of the fillers in the aerobic zone 3013 and the anoxic zone 3014. The center position of the anoxic zone 3014 is divided into a third sedimentation unit 3018, which is used for sedimentation separation of the wastewater subjected to denitrification reaction. The third drainage unit 3015 is used for discharging the wastewater subjected to sedimentation separation.

[0189] Specifically, the reflux unit 302 includes a water inlet end and a water outlet end, the water inlet end is communicated with the anoxic zone 3014, the water outlet end is communicated with the second water inlet unit 3011, the reflux unit 302 refluxes the wastewater in the anoxic zone 3014 to the second water inlet unit 3011 for continuous cyclic treatment, the second control valve 303 is arranged at the water outlet end of the reflux unit 302, for controlling the water outlet amount of the reflux unit 302. The oxygen content in the anoxic zone 3014 is ensured to be in the range of less than 1 mg / L. The wastewater to be treated enters the second main tank body 301 through the second water inlet unit 3011, and the hydrolysis acidification reaction and ammoniation reaction are carried out in the anaerobic zone, so that the organic nitrogen in the wastewater is converted into ammonia nitrogen, the nitrification reaction is carried out in the aerobic zone, so that the ammonia nitrogen in the wastewater after the anaerobic zone is converted into nitric acid nitrogen, the denitrification reaction is carried out in the anoxic zone, so that the nitric acid nitrogen in the wastewater after the aerobic zone is converted into nitrogen, that is, the treatment of total nitrogen in the wastewater is completed. Part of the water after the denitrification reaction is subjected to sedimentation separation through the third sedimentation unit 3018, the separated water is discharged through the third water discharge unit 3015, and the other part of the water is refluxed to the second water inlet unit 3011 for continuous cyclic treatment through the reflux unit 302. By adding the reflux unit 302, the wastewater after the nitrification reaction in the anoxic zone 3014 can be refluxed to the second water inlet unit 3011 for cyclic treatment, the reflux unit 302 refluxes the wastewater after the denitrification reaction in the anoxic zone 3014 to the second water inlet unit 3011 for continuous reaction of converting the nitric acid nitrogen into nitrogen, and the treatment of total nitrogen is completed. By adding the reflux unit 302, the wastewater after the denitrification reaction in the anoxic zone 3014 can be refluxed to the water inlet unit 3011 for cyclic treatment, so that the wastewater treatment is more thorough, at the same time, the wastewater entering the water inlet unit 3011 can be diluted in toxicity, the survival rate of the nitrifying bacteria in the aerobic zone 3013 and the denitrifying bacteria in the anoxic zone 3014 is improved, the efficiency of wastewater treatment is improved, and the process flow is simplified.

[0190] In addition, in the embodiment of the present application, the aerobic zone 3013 and the anoxic zone 3014 are combined in the vertical space of the second main tank body 301, the aerobic zone and the anoxic zone are integrally arranged, on the one hand, the nitrification reaction and the denitrification reaction can be sequentially and synchronously carried out without interference with each other, and the wastewater process flow is simplified; on the other hand, the space utilization rate of the second main tank body 301 is increased, the volumetric loading of the second main tank body 301 is improved, the occupied area is only half of that of the traditional process, and the operation cost is low.

[0191] As Figure 15As shown, in some embodiments of the present application, the reflux unit 302 comprises a first water tank 3021, a third water inlet pipe 3022 and a second water outlet pipe 3023. The first water tank 3021 is annular and arranged outside the top outer wall of the second main tank body 301, and the third water inlet pipe 3022 is configured as a square pipe with a filter screen arranged on the pipe wall to achieve multi-surface water inlet filtration, improve water inlet rate and further speed up wastewater treatment efficiency. The filter screen can also prevent the filler in the anoxic zone 3014 from flowing into the first water tank 3021. The number of third water inlet pipes 3022 is preferably four and evenly distributed on the inner side of the inner wall of the second main tank body 301. The four third water inlet pipes 3022 are respectively connected to the first water tank 3021 and the anoxic zone 3014, and form the water inlet end of the reflux unit 302. The second water outlet pipe 3023 is preferably provided with two, which are evenly distributed on the bottom of the first water tank 3021. The two second water outlet pipes 3023 are respectively connected to the first water tank 3021 and the second water inlet unit 3011, and form the water outlet end of the reflux unit 302. Water pumps are arranged on the two second water outlet pipes 3023 to pump the wastewater in the anoxic zone 3014, or a jet device is arranged in the pipeline of the second water inlet unit 3011 to pump the wastewater in the anoxic zone 3014. The jet device is a prior art and the specific principle is not described herein. The second control valve 303 is arranged on the two second water outlet pipes 3023, which is preferably an electromagnetic valve or a pneumatic valve, and the present embodiment is not limited. The four third water inlet pipes 3022 are evenly distributed on the inner side of the inner wall of the second main tank body 301, which can make the water flow more uniform when the water pump or jet device pumps the wastewater in the anoxic zone 3014, and also can improve the reflux speed of the wastewater, realize large-scale reflux of nitrification liquid and further improve the wastewater treatment efficiency.

[0192] As shown, Figure 16 In some embodiments of the present application, the second water inlet unit 3011 comprises a main pipe 30111 and a branch pipe 30112. The main pipe 30111 is a four-way pipe, and two ends of the main pipe 30111 are respectively connected to the two second water outlet pipes 3023. The branch pipe 30112 is also a four-way pipe, one end of which is connected to the external wastewater pipeline, and the branch pipe 30112 is arranged below the main pipe 30111. The branch pipe 30112 and the main pipe 30111 are also connected by a plurality of vertical short pipes 30113. A plurality of spray heads 30114 are evenly distributed on the branch pipe 30112, and a sludge discharge valve is arranged at the other end of the branch pipe 30112 to discharge the sludge in the branch pipe 30112.

[0193] As shown, Figure 17 and Figure 18As shown, in some embodiments of the present application, the aeration assembly 3016 comprises an aeration main pipe 30161 and a plurality of aeration sub-pipes 30162. The aeration main pipe 30161 is connected to an external air blower, and the plurality of aeration sub-pipes 30162 are arranged in multiple layers, preferably two layers in this embodiment, or can be adjusted according to the specific cross-sectional area of the second main tank body 301 and the amount of wastewater to be treated, which is not limited in this embodiment.

[0194] In this embodiment, ten aeration sub-pipes 30162 are arranged in the upper layer and seven aeration sub-pipes 30162 are arranged in the lower layer, with an interval of 0.15 meters between each aeration sub-pipe 30162. The distribution direction of the aeration sub-pipes 30162 in the upper layer is different from that of the aeration sub-pipes 30162 in the lower layer by 90°. Each layer of aeration sub-pipes 30162 is connected to the aeration main pipe 30161. The aeration main pipe 30161 can be arranged in one of the layers, or both layers, which is not limited in this embodiment. In addition, a plurality of air holes are arranged on each layer of aeration sub-pipes 30162, which generate small bubbles of about 1 mm to increase the contact area and contact time with the wastewater, thereby improving the oxygen transfer efficiency and further improving the wastewater treatment efficiency.

[0195] As shown in the drawings, Figure 19 In some embodiments of the present application, the filter plate 3017 comprises a frame 30171 and a first filter screen 30172. The frame 30171 is circular, and the outer wall of the frame 30171 is fixedly connected to the inner wall of the second main tank body 301. The first filter screen 30172 is arranged on the frame 30171. The first filter screen 30172 is used to filter the wastewater flowing from the aerobic zone 3013 to the anoxic zone 3014, so as to prevent the fillers in the aerobic zone 3013 and the anoxic zone 3014 from flowing into each other. The first filter screen 30172 can completely separate the upper and lower spaces of the aerobic zone 3013 and the anoxic zone 3014 in the second main tank body 301. The nitrification reaction and the denitrification reaction can be performed synchronously and sequentially without interference, thereby achieving the integrated arrangement of the aerobic zone and the anoxic zone and simplifying the wastewater process flow.

[0196] As shown in the drawings, Figure 13As shown, in some embodiments of the present application, the third sedimentation unit 3018 comprises a second tank 30181, third inclined pipes 30182 and a second sludge discharge pipeline 30183. The second tank 30181 is funnel-shaped, i.e. the upper part is a rectangular or square tank and the lower part is a funnel-shaped tank. The rectangular or square tank and the funnel-shaped tank are spliced together to form the second tank 30181. The third inclined pipes 30182 are arranged in multiple numbers and uniformly spaced on the upper part of the second tank 30181, preferably arranged on the entire upper part of the second tank 30181. A plurality of water inlet holes are provided on the sidewall of the bottom of the second tank 30181, which are uniformly distributed on the sidewall of the bottom of the second tank 30181. The bottom of the second tank 30181 is also provided with the second sludge discharge pipeline 30183. The water flow after the denitrification reaction enters the second tank 30181 through the water inlet holes on the sidewall of the bottom of the second tank 30181, and slowly flows through the third inclined pipes 30182 as the water flow rises. The denitrification reaction product and sludge slide down the third inclined pipes 30182, gradually achieving sedimentation and separation of the wastewater after the denitrification reaction. The separated granular sludge gradually aggregates into large sludge, which falls to the bottom of the second tank 30181 due to gravity. The sludge is discharged through the second sludge discharge pipeline 30183 provided at the bottom of the second tank 30181. The water inlet holes are preferably small holes through which the mud-water mixture can pass, but large sludge and fillers cannot pass.

[0197] The sidewall of the second tank 30181 can also be provided with a three-phase separation structure for mud, water and gas. The three-phase separation structure is specifically as follows Figure 7As shown in the figure, the upper part of the box is a sectional view of the side wall, the left side of the side wall is the third sedimentation unit 3018, the right side of the side wall is the anoxic zone 3014, the first water inlet 30184 and the second water inlet 30185 are arranged on the side wall in an up-down distribution, the first water inlet 30184 is provided with a first baffle 30186 above the side of the third sedimentation unit 3018, the first baffle 30186 is inclined downward towards the center of the third sedimentation unit 3018, the second water inlet 30185 is provided with a second baffle 30187 below the side of the third sedimentation unit 3018, the second baffle 30187 is inclined upward towards the center of the third sedimentation unit 3018, the sludge, water and gas mixed liquid after the denitrification reaction in the anoxic zone 3014 slowly enters the third sedimentation unit 3018 through the first water inlet 30184 and the second water inlet 30185, the bubbles in the water are blocked by the first baffle 30186, and then are discharged back to the anoxic zone 3014 through the first water inlet 30184, as the water flow rises, the sludge in the mixed liquid slides down through the second baffle 30187, and then is discharged back to the anoxic zone 3014 through the second water inlet 30185, the sludge, water and gas three-phase separation structure is realized through the first water inlet 30184, the second water inlet 30185, the first baffle 30186 and the second baffle 30187, the sludge, water and gas mixed liquid after the denitrification reaction in the anoxic zone 3014 is further separated, and the sedimentation and separation effect of the third sedimentation unit 3018 is improved.

[0198] In some embodiments of the present application, the third water discharge unit 3015 includes a second water discharge pipe 30151 arranged on the top of the second main tank body 301, one end of the second water discharge pipe 30151 communicates with the third sedimentation unit 3018, and the other end of the second water discharge pipe 30151 communicates with an external second water discharge pipe 30151, so as to ensure the water discharge amount.

[0199] As shown in the figure, Figure 21 and Figure 22 In some other embodiments of the present application, the nitration-denitrification integrated reactor 3 further includes a backwashing assembly 304 for cleaning the filler in the second main tank body 301.

[0200] The backwashing assembly 304 includes a second water tank 3041, an air outlet pipe 3043 and a second air outlet valve 3044, the second water tank 3041 is annular and arranged outside the outer wall of the aerobic zone 3013, the wall body of the aerobic zone 3013 is circumferentially provided with an air outlet 3042 for communicating the second water tank 3041 and the aerobic zone 3013, the air outlet 3042 can be circumferentially arranged on the inner wall of the second main tank body 301 or uniformly distributed at intervals, and the present application does not limit the distribution mode of the air outlet 3042.

[0201] The backwashing assembly 304 in the embodiment further comprises two air outlet pipes 3043, which are circumferentially and evenly arranged on the top of the second water tank 3041, and are respectively connected to the second water tank 3041 and the anoxic zone 3014. The second air outlet valves 3044 are arranged on the two air outlet pipes 3043 respectively. When aeration is performed in the aerobic zone 3013, the gas-water mixture in the aerobic zone 3013 enters the second water tank 3041 through the air outlet 3042 for storage. When the second water tank 3041 reaches a certain air pressure, the air outlet valves on the two air outlet pipes 3043 are opened, and the gas-water mixture is instantaneously discharged through the air outlet pipes 3043. The discharged gas-water mixture flows from the anoxic zone 3014 to the aerobic zone 3013, thereby cleaning the fillers in the anoxic zone 3014 and the aerobic zone 3013. The impact force of the downward flow of the gas-water mixture can wash away the dead biological layer on the fillers, so that the dead biological layer falls off and falls to the bottom of the second main tank 301 to form sludge which is discharged. In this embodiment, the end portions of the two air outlet pipes 3043 in the anoxic zone 3014 can be arranged in a curved structure towards the bottom of the second main tank 301, so that the impact force of the gas-water mixture is directed towards the bottom of the second main tank 301 when the gas-water mixture is instantaneously discharged, thereby better cleaning the fillers in the anoxic zone 3014 and the aerobic zone 3013 and further improving the wastewater treatment efficiency.

[0202] In some other embodiments of the present application, a second filter screen 3045 is arranged on the air outlet 3042, which is used to filter the wastewater flowing from the aerobic zone 3013 to the second water tank 3041, so as to prevent the fillers in the aerobic zone 3013 from flowing into the second water tank 3041. A second baffle 3046 is arranged on the air outlet 3042 and is inclined downward towards the center of the second main tank 301, which is used to block the bubbles in the aerobic zone 3013. When aeration is performed in the aerobic zone 3013, a part of the gas-water mixture flowing through the second baffle 3046 will flow below the second baffle 3046. Under the blocking action of the second baffle 3046, the gas-water mixture enters the second water tank 3041 through the air outlet 3042 for storage. The filter holes on the second filter screen 3045 on the air outlet 3042 can only allow water to pass through, and the fillers in the aerobic zone 3013 cannot pass through, so as to prevent the fillers in the aerobic zone 3013 from flowing into the second water tank 3041.

[0203] The traditional nitrification and denitrification processes need to be performed in two independent reactors (A 2O), or in the same reactor which causes the alternate anoxic and aerobic environment in time or space (SBR). The traditional biological denitrification process mainly has two kinds of pre-denitrification and post-denitrification. The pre-denitrification can utilize part of the fast-degradable organic matter in wastewater as carbon source, although the cost of additional carbon source in the denitrification stage can be saved, but the pre-denitrification process is not complete for nitrogen removal, and the wastewater and sludge circulation ratio is also high, if a higher total nitrogen removal rate is to be obtained, the circulation ratio must be increased, and the energy consumption is also increased. While the post-denitrification relies on the addition of fast-degradable organic carbon source, and a large amount of sludge is also produced, and the COD in the effluent and the low level of DO also affect the effluent quality.

[0204] The problems of the traditional biological denitrification process are: (1) the process flow is long, the land occupation area is large, and the capital investment is high; (2) due to the slow proliferation speed of nitrifying bacteria and the difficulty in maintaining a high biological concentration, especially in winter, the system HRT is long, a large aeration tank is needed, and the investment and operation cost is increased; (3) in order to maintain a high biological concentration and obtain good denitrification effect, sludge and nitrification liquid reflux must be carried out, which increases the power consumption and operation cost; (4) the system has weak impact resistance, high concentration NH3-N and NO2 - Wastewater inhibits the growth of nitrifying bacteria; (5) the acidity generated in the nitrification process needs to be neutralized by adding alkali, which not only increases the treatment cost, but also may cause secondary pollution, etc.

[0205] The nitrification-denitrification integrated reactor 3 provided by the embodiment of the present application divides the second main tank body 301 into: an anoxic zone 3014 and a third sedimentation unit 3018 in the upper part, an aerobic zone 3013 in the middle part, and an anaerobic zone 3012 in the lower part, and the anoxic zone 3014 and the aerobic zone 3013 are filled with fillers, so that the anoxic zone 3014 and the aerobic zone 3013 have stable ecological conditions, and the nitrifying bacteria in the aerobic zone 3013 and the denitrifying bacteria in the anoxic zone 3014 form a long biological chain, so that the nitrifying bacteria and the denitrifying bacteria can coexist in the same place, have the ability of simultaneous nitrification and denitrification and organic matter removal, simplify the wastewater process flow, improve the volume load of the main tank body, further improve the wastewater treatment efficiency, and at the same time reduce the energy consumption and cost of the treatment process.

[0206] Macro-environment explanation: due to the uneven mixing form of the biological reactor, such as different oxygenation devices, an anoxic and / or anaerobic section can be formed in the biological reactor, which is the macro-environment of the biological reactor. In the production scale biological reactor, the entire reactor is not in a completely homogeneous mixing state, so the nitrification-denitrification integrated reactor is also realized.

[0207] The micro-environment theory is explained from the physical point of view, considering the transfer and change of various substances (such as DO, organic matter, etc.) in the micro-environment of activated sludge and biofilm, the metabolic activities of various microorganisms and their interactions, and the changes of the physical, chemical and biological conditions or states of the micro-environment. The micro-environment theory believes that due to the limitation of oxygen diffusion, a DO gradient (as shown in Figure 23 ) is generated in the microbial floc, resulting in simultaneous nitrification and denitrification of the micro-environment.

[0208] The outer surface of the microbial floc has a higher DO, dominated by aerobic nitrifying bacteria; deep into the floc, oxygen transfer is blocked and a large amount of external oxygen is consumed, resulting in an anoxic zone, where denitrifying bacteria are dominant. The anoxic environment in the microbial floc is the main reason for the formation of SND, and the formation of the anoxic environment depends on the DO concentration in the water and the structure of the microbial floc. Therefore, controlling the DO concentration and the structure of the microbial floc is crucial for simultaneous nitrification and denitrification.

[0209] a. Short-cut nitrification and anaerobic ammonia oxidation

[0210] Anaerobic oxidation of ammonia has many outstanding advantages. Mainly in: (1) no additional organic matter as electron donor, not only can save cost, but also can prevent secondary pollution; (2) nitrification reaction consumes 2 mol of oxygen for every 1 mol of NH4 + , while in the anaerobic ammonia oxidation reaction, only 0.75 mol of oxygen is needed for every 1 mol of NH4 + , a decrease of 62.5% (not considering cell synthesis), so the oxygen consumption can be greatly reduced; traditional nitrification reaction can produce 2 mol of H + for every 1 mol of NH4 + , denitrification reduces 1 mol of NO3 - or NO2 - to produce 1 mol of OH - , while the acid production of anaerobic ammonia oxidation is greatly reduced, and the alkali production is reduced to zero, which can save considerable neutralizing agent.

[0211] Referring to Figure 24 , the reaction formula is illustrated as follows:

[0212] 0.5NH4 + + 0.75O2----5NO2 - + 0.5H2O + H +

[0213] 0.5NH4 + + 0.5NO2 - ----5N2 + H2O

[0214] The total reaction formula is illustrated as follows:

[0215] NH4 + + 0.85 02→ 0.435 N2+ 0.13 N03 - + 1.3 H2O + 1.4 H +

[0216] b. Realization of aerobic denitrification / heterotrophic nitrification technology

[0217] The aerobic denitrification bacteria include Pseudomonas Spp, Alcaligenes faecalis, Thiosphaera Pantotropha and many other bacteria, and are also heterotrophic nitrification bacteria. The discovery of the aerobic denitrification bacteria and the heterotrophic nitrification bacteria breaks the traditional theory that the nitrification reaction can only be completed by autotrophic bacteria and the denitrification can only be carried out under anaerobic conditions. The aerobic denitrification bacteria, the heterotrophic nitrification bacteria and the autotrophic denitrification bacteria widely exist in the Pseudomonas, Alcaligenes, Paracoccus and Bacillus, such as the denitrifying Thiosphaera, the denitrifying Microspira, the versatile Thiosphaera, the Pantotropha and the Paracoccus.

[0218] The aerobic denitrification can occur in the same reactor as the nitrification reaction, reduces the system space and the engineering cost, and does not need additional alkali to adjust the pH value of the system. The aerobic denitrification bacteria are easier to be controlled in the treatment operation.

[0219] When the dissolved oxygen (DO) concentration in the reactor reaches below 0.5 mg / L, the ammonia-oxidizing bacteria AOB oxygen saturation constant 0.2-0.4 mg / L is not affected, while the nitrite-oxidizing bacteria NOB oxygen saturation constant 1-2 mg / L is inhibited. Under the limited oxygen condition, there are two types of autotrophic microorganisms in the system: aerobic nitrification bacteria and anaerobic ammonia-oxidizing bacteria. The autotrophic bacteria directly convert NH4 - into N2 through the NO2 + intermediate.

[0220] The aerobic denitrification nitrogen removal efficiency of the aerobic denitrification bacteria in the coking wastewater with different ammonia nitrogen concentrations is shown in the following table:

[0221]

[0222] From the content of the above table, it can be seen that the denitrification rate decreases with the increase of the ammonia nitrogen concentration; the strain has strong deamination ability and ammonia tolerance in the coking wastewater, and can still remove ammonia nitrogen under the ammonia nitrogen concentration of 3400 mg / L.

[0223] c. C / N / S simultaneous removal technology

[0224] Autotrophic denitrifying bacteria are divided into hydrogen type, sulfur type, iron type and ammonia type (autotrophic ammonia oxidation). In the treatment of coking wastewater, sulfur type and ammonia type (introduced in a) are mainly used. Traditional heterotrophic denitrification refers to the process that denitrifying bacteria take organic matter as a carbon source and an electron donor to provide energy, so as to reduce nitrate and nitrite to nitrogen. Autotrophic denitrification takes hydrogen, elemental sulfur, sulfide, iron or iron ions, ammonia nitrogen and other reducing substances as electron donors. The integrated technology mainly utilizes the heterotrophic action of anaerobic zone sulfate-reducing bacteria to generate sulfide, and the autotrophic denitrification of sulfur bacteria to remove nitrate to generate elemental sulfur and nitrogen gas, as shown in the following formula. Figure 25

[0225] The biological selection zone consumes organic matter and sulfate reduction, for example: 100gCOD + 150.2gSO4 2- + 43.7gH2O→53.2gH2S + 1.9g sludge + 190.9gHCO3 - The anoxic zone undergoes sulfur autotrophic denitrification reaction, for example: 100gNO3 - + 5.9gHCO3 - + 35.92gH2S→22.58gN2 + 101.42gSO4 2- + 2.15g sludge

[0226] The aerobic zone undergoes nitrification reaction, for example: 100gNH4 + + 7.3gCO2 + 346.67gO2→5.22g sludge + 344.44gNO3 - + 11.11gH + + 98gH2O

[0227] Through autotrophic denitrification such as sulfur cycle, not only the oxygen consumption in the COD removal process is reduced, but also the residual sludge is zero discharged through three kinds of biochemical reactions with low sludge yield. The sludge yield is only 0.04g-vss / gCOD.

[0228] The second electrochemical precipitator: in the embodiment of the present application, the second electrochemical precipitator 5 has the same structure as the first electrochemical precipitator 1, and the difference between the two lies in the different fillers of the electrodes. In the second electrochemical precipitator 5, the second anode filler is arranged in the anode plate 1014, the second anode filler includes at least one of γ-OOFe, FeO, FeCO3, Al, VO, CuO and a complexing agent, and the second anode filler further includes protocatechuic acid and hydrothermal carbon. The cathode includes a carbon nano-RVC blowing fluidized electrode. The water collecting assembly is used to collect wastewater after electrochemical reaction. The difference between the second anode filler and the first anode filler lies in the different ratios of the components, and the second anode filler focuses on removing heavy metal ions in wastewater. ​

[0229] Desalination module 4: as shown in the embodiment of the present application, the desalination module 4 comprises a first RO device 401, an NF device 402, a second RO device 403 and a bipolar membrane electrodialysis device 404 connected in sequence. Figure 26

[0230] According to the water quality characteristics of coal chemical wastewater, the process selection and process of the concentrated brine pretreatment unit, the membrane integrated concentration and reduction unit and the high-concentration brine resource utilization unit are designed. The concentrated brine after biochemical reuse has a high salt content, usually more than 15000 mg / L; the COD content is basically difficult to biodegrade organic matter; the fluorine ion content is very high, usually more than 150 mg / L, the Si content is relatively high, usually more than 50 mg / L, and the hardness is not high. The water quantity is usually not large, and the concentrated brine quantity varies from several dozen tons to several hundred tons per hour with different coking scales.

[0231] The key of the pretreatment unit is to remove residual COD, F - , Si and hardness treatment process, the traditional process uses O3+H2O super oxidation or chemical Fenton oxidation+three-way box silicon removal, hardness removal, and a series of reagents such as pH regulator NaOH\HCl, flocculant poly iron salt\PAM, silicon removal agent CaO, hardness removal agent NaCO3 need to be added, which will affect the subsequent operation and salt precipitation purity; the coal chemical wastewater contains a lot of colloids, which need to be removed by ultrafiltration. The main salt in the water is sodium sulfate and sodium chloride, and a small amount of K + , F - , and a salt separation nanofiltration membrane is used for salt separation. The concentrated and dilute water sides after salt separation use membrane integrated process for concentration respectively.

[0232] The nanofiltration concentrated water side is mainly concentrated sodium sulfate, and the COD is mainly in the nanofiltration concentrated water side. The concentration of concentrated sodium sulfate is about 3.5% to 5%, and the COD is about 100 mg / L. Traditionally, the nanofiltration of concentrated water is used to further concentrate the sodium sulfate concentration to 6% to 12%, or the steam mechanical re-compression technology is used for evaporation concentration. The embodiment of the present application uses the sodium sulfate solution after salt separation to rely on bacterial biochemical treatment.

[0233] The nanofiltration water side is mainly sodium chloride, the concentration is about 1% to 1.5%, the COD content is less than 20 mg / L, and the divalent ion content is usually low, which is not easy to be polluted by organic matter and scaled by inorganic matter, and the water quality is relatively good. Usually, the reverse osmosis is used to further concentrate the sodium chloride concentration to 8% to 10%, or the reverse osmosis is used to concentrate the sodium chloride concentration to 4% to 5%, and then the electrodialysis is used to concentrate to 16% to 20%.

[0234] ​​The traditional process is concentrated by membrane method / thermal method after salt separation to reduce the treatment capacity of subsequent high-concentration brine, and all the waste liquid after concentration needs energy for evaporation or freezing treatment, which consumes a lot of energy. Moreover, the current production process and equipment operation are extremely unstable, it is difficult to reach the purity required by the national standard for sodium sulfate salt, and the application field of sodium sulfate salt is small, which is difficult to sell and reuse. The application adopts sulfate-reducing bacteria (SRB) to treat the sodium sulfate concentrated liquid, and combines with autotrophic denitrifying sulfur bacteria (T-denitrificans) to generate elemental sulfur. The advantages are:

[0235] 1) Sulfate-reducing bacteria (SRB) and denitrifying sulfur bacteria (T-denitrificans) are common natural bacteria, which are easy to obtain.

[0236] 2) The sulfate-splitting device has simple structure, low cost and low operation cost, and does not need to add a large amount of reagent.

[0237] 3) The product is sulfur-containing elemental sludge, which is a very good soil conditioner.

[0238] 4) The concentrated water on the side of the divalent salt does not need to consume energy for evaporation (freezing) crystallization, which saves a lot of energy.

[0239] 5) The system runs stably.

[0240] In the embodiment of the application, the resource utilization of high-concentration brine is to produce sodium chloride by evaporation crystallization process or to produce hydrochloric acid and sodium hydroxide by a bipolar membrane method.

[0241] The high-concentration sodium chloride brine is usually dried by evaporation crystallization to produce sodium chloride meeting the standard for sale. According to the composition of the mother liquor and the impure salt and the system operation, part of the reflux is used to reduce the impure salt rate and improve the sodium chloride recovery rate. The mother liquor is transported to the impure salt evaporator for evaporation and drying and then is transported out for disposal.

[0242] In a factory or industrial park, the high-concentration sodium chloride brine is used to produce about 2mmol / L concentration of hydrochloric acid and sodium hydroxide by a bipolar membrane, which is used in the production of the factory or industrial park, which is an advanced technology and suitable for resource utilization of high-concentration brine. Considering the economy of investment and operation cost, the concentration of the brine entering the bipolar membrane is usually ≥5%, which can usually meet the concentration requirement through the front-end membrane integrated concentration unit. The bipolar membrane has high requirements for the water quality of the concentrated brine. In order to obtain high-quality acid and alkali, the concentrated brine needs to be purified as much as possible. In the pretreatment section, the COD in the water and the ions other than Na + , Cl - , SO4 2- are removed as much as possible, and the pretreatment of high-concentration brine is done well. Chelating resin is used to remove Ca 2+ , Mg 2+ in the high-concentration brine, and resin adsorption is used to remove F -, the high-concentration salt water meeting the water inlet requirement enters the bipolar membrane to produce sulfuric acid / hydrochloric acid and sodium hydroxide.

[0243] As shown in Figure 1 , in the embodiment of the present application, the desalination module 4 is sequentially provided with a precipitation device 11 and a filtration device 12 between the second electrochemical precipitator 5. Specifically, in some embodiments of the present application, the precipitation device 11 and the filtration device 12 are respectively a high-density precipitator and a tubular microfiltration device, which can remove fine solid impurities in the wastewater before entering the desalination module 4.

[0244] As shown in Figure 1 , in the embodiment of the present application, the equipment coal chemical wastewater treatment system further comprises a first sludge concentration and dehydration module and a second sludge concentration and dehydration module, the first sludge concentration and dehydration module comprises a first sludge concentration tank 13 and a first sludge dehydration tank 14 connected in sequence, and the second sludge concentration and dehydration module comprises a second sludge concentration tank 15 and a second sludge dehydration tank 16 connected in sequence; the first electrochemical precipitator 1, the hydrolysis acidification reactor 2 and the nitrification-denitrification integrated reactor 3 are respectively connected with the first sludge concentration tank 13, and the precipitation device 11 is connected with the second sludge concentration tank 15. By arranging the first sludge concentration and dehydration module and the second sludge concentration and dehydration module, the sludge generated in the first electrochemical precipitator 1, the hydrolysis acidification reactor 2, the nitrification-denitrification integrated reactor 3 and the precipitation device 11 can be respectively concentrated and dehydrated.

[0245] As can be known from the above description of the embodiments, the equipment coal chemical wastewater treatment system provided by the present application at least has the following advantages:

[0246] Superior effluent index: the coal chemical wastewater is difficult to degrade, and the COD can be degraded with high efficiency and relatively completely, the removal rate of volatile phenol is greater than 99.9%, the removal rate of cyanide is greater than 99.9%, the removal rate of COD is greater than 99%, the effluent COD is less than 80 mg / L, the removal rate of ammonia nitrogen is greater than 99%, the effluent is less than 5 mg / L, and the removal rate of total nitrogen is greater than 98.5%, and the effluent is less than 10 mg / L.

[0247] Energy saving and consumption reduction: the aerobic aeration amount is reduced to more than half of that of the traditional process, no electric water pump for mixed liquid and sludge backflow is needed, no sludge scraping equipment is needed, and the overall process energy consumption is half of that of the traditional process.

[0248] Land saving: the overall process is equipment, the efficiency is improved, auxiliary facilities are simplified, and the land area is half of that of the traditional process.

[0249] Simple and automatic control, simple operation and management, high efficiency and stability.

[0250] Simple process operation parameters and high automation degree.

[0251] The device-based coal chemical wastewater treatment method provided by the present application is described in detail below, and the device-based coal chemical wastewater treatment method described below can be correspondingly referred to the device-based coal chemical wastewater treatment system described above.

[0252] The conventional design based on the traditional A / O and its modified process needs to build a large number of large-volume reinforced concrete reaction tanks, the process flow is long, the land occupation is large (the traditional process considers that nitrification and denitrification cannot be performed simultaneously), the construction cost is high, and no mature device is formed.

[0253] The process is complex, and the operation cost is high. The nitrifying bacteria population in the aerobic tank has a slow reproduction speed and is difficult to maintain a high concentration, and requires a high dissolved oxygen concentration; the traditional aeration method has a small oxygen transmission efficiency and a low oxygen utilization rate, and not only a large aeration tank needs to be built, but also a powerful aeration and oxygenation capacity is needed. More than 60% of the overall energy consumption of the activated sludge treatment method is consumed in the power consumption of the aeration blower. At the same time, a large amount of backflow design needs to be completed by an electric pump. Due to the efficiency and the limitation of the adjustment range of the electric pump, the power cost is wasted. The independent nitrification process produces acid, which needs to be neutralized by adding alkali, and the multi-stage sedimentation tank process increases the consumption of reagents. The system has a weak impact resistance, and high concentrations of NH3-N and NO2 - will inhibit the growth of nitrifying bacteria.

[0254] The traditional process design has a long process flow, various sludge backflow and nitrification liquid backflow process control means directly affect the main process control parameters, the process adjustment is complex and changeable, the treatment effect is affected by the large fluctuation of the coal chemical wastewater quality and temperature, the operation conditions are required to be relatively strict, the automatic control means is lacking, and the personnel operating experience is required to be high.

[0255] In the prior art, the coal chemical wastewater is generally treated by a two-stage treatment process of pretreatment and biochemical treatment, and further treated by a three-stage deep treatment process of activated carbon, strong oxidation and biological membrane technology. The traditional nitrification and denitrification isolation treatment technology is still the center, and the new total nitrogen removal technology developed in recent years has not formed industrialization and device. In the prior art, the three-stage treatment is composed of dephenolization, ammonia distillation, biological treatment and activated carbon adsorption, and is a process flow composed of various physical and chemical methods with biological treatment as the center. At present, most wastewater treatment systems adopt a one-stage treatment and a two-stage treatment process. The one-stage treatment refers to the recovery and utilization of pollutants in high-concentration wastewater, and the process includes ammonia water dephenolization, ammonia water distillation, final cooling water decyanation and the like. The two-stage treatment mainly refers to mixing the effluent after the one-stage pretreatment with other coal chemical wastewater, harmlessly treating the phenol cyanide wastewater, and entering a treatment system mainly based on biochemical methods, such as activated sludge method, A-O tank, SBR tank and the like. The three-stage deep treatment refers to re-purification when the effluent after the biochemical treatment still cannot meet the discharge standard. The main process includes activated carbon adsorption method, carbon biological membrane method, coagulation sedimentation method and oxidation pond method.

[0256] Coal chemical wastewater usually has the largest proportion of phenol and its derivatives, about 60% or more of the total mass, and toxic substances such as heterocyclic compounds, polycyclic aromatic hydrocarbons, quinoline, benzene and other refractory organic matter account for more than 1 / 3. The higher the proportion of refractory organic matter, the more difficult it is to achieve good biochemical treatment effect.

[0257] For refractory organic matter in coal chemical wastewater, the traditional process treatment effect is not ideal, the effluent COD concentration is high, and it is difficult to meet the requirements of the discharge standard for COD. Therefore, each wastewater station prolongs the hydraulic retention time of the aeration tank to improve the treatment effect, and the tHRT is prolonged to 24h, 36h, even 48h or longer. Because the structure of polycyclic aromatic hydrocarbons and heterocyclic compounds in coal chemical wastewater is complex, a long time is needed for the degradation process, and prolonging the hydraulic retention time plays a certain improvement role in the treatment effect, but the effluent quality is still difficult to meet the requirements of the wastewater discharge standard for COD. In addition, the conventional biological treatment has no obvious removal effect on ammonia nitrogen, and cannot meet the control requirements of the wastewater discharge standard for ammonia nitrogen. The CODCr of the effluent wastewater of most domestic coking plants does not meet the standard.

[0258] Insufficient attention is paid to the pretreatment of coal chemical wastewater, the pretreatment is insufficient, and the subsequent traditional process has insufficient resistance to impact load, resulting in poor system operation stability.

[0259] Due to the particularity of the coal coking production process, the phenol or ammonia nitrogen concentration in the influent will change dramatically, and the pretreatment can only rely on the temporary storage and treatment of the emergency tank, and the subsequent biological treatment is difficult;

[0260] The chemical cyanide breaking technology is efficient, but the operating parameters are difficult to control in time, so the treatment result is not very effective, and a large amount of chlorine-containing oxidizing agent and pH adjusting agent needs to be added, introducing new pollutants.

[0261] The traditional air flotation and initial exposure tank introduce oxygen molecules early, which oxidize some phenolic substances into quinones that are difficult to biodegrade, resulting in excessive COD and color of the effluent.

[0262] The overall traditional treatment process does not pay enough attention to the anaerobic treatment link, and some production lines do not set up anaerobic link. Due to process defects, the volume load and sludge load are low, and the operation effect is poor. The particularity of coal chemical wastewater makes the methanogenic bacteria activity low and the generation cycle long, and it is difficult to carry out efficient biochemical reaction. The coal chemical wastewater needs to be hydrolyzed and acidified to the stage, which can break the large benzene ring and heterocyclic substances, improve the BOD5 and COD ratio, and create good biochemical reaction conditions for subsequent treatment, which is the purpose of the anaerobic process of coal chemical wastewater.

[0263] The conventional coal chemical wastewater advanced treatment "zero discharge" process is not perfect enough The advanced treatment of coal chemical wastewater is mainly based on chemical treatment, but single chemical treatment method cannot achieve effective treatment results. The commonly used advanced treatment methods in practice are physical treatment method and chemical treatment method. In order to achieve the wastewater treatment water quality specified in the regulations, several treatment methods are usually combined. Since the advanced treatment of domestic coal chemical wastewater has just started, the commonly used treatment processes are: wet coke quenching, blast furnace slag flushing, coal yard dust suppression, converter gas washing water, dust removal water, sintering mixing and industrial water supply, etc. These processes still have certain defects, and secondary pollution transfer and serious water resource waste are prone to occur. The main reasons are: domestic enterprises mostly choose the process combining chemical treatment and membrane separation in the aspect of coking advanced treatment. On the one hand, the treatment membrane in the membrane separation link is prone to be polluted, and the membrane cleaning is frequent and the service life of the membrane is limited, etc. The water quality after the treatment of this process cannot completely meet the standards. On the other hand, the repeated use of the treatment membrane causes secondary pollution problem. Influenced by the equipment investment cost, the cost of frequent replacement of the treatment membrane is too high, and many enterprises are mostly unwilling to invest in the equipment maintenance fund in this aspect. The coal chemical concentrated salt water desalination technology is under discussion, the existing technology cannot completely remove the divalent salt, the impurity content is large, and the final product does not meet the standards and causes difficult-to-treat hazardous solid.

[0264] The triple tank high-density sedimentation tank in the prior art has the functions of removing COD and hardness, the flocculant dosage is very large, 500-1000 mg / L per month, and the turbidity of the produced water is acceptable. Since F - , the removal effect of COD needs to be operated at pH 7-8, and the removal effect of hardness needs to be operated at pH 11-12 under alkaline conditions, so it needs to be operated in stages, that is, the five-tank method, which causes a large amount of acid and alkali dosage.

[0265] The ozone catalytic oxidation process has a very low COD removal efficiency for the concentrated salt water with a high salt content of 10000-20000, the operation is only 20%, and the requirements of the subsequent salt evaporation system, membrane system stable operation and salt purity cannot be met.

[0266] The membrane element of the ultrafiltration system is often polluted due to the influence of the front-end dosing agent.

[0267] The concentrated salt water (divalent salt) after nanofiltration MVR falling film evaporator has foam in the evaporation chamber due to the pretreatment effect, the secondary steam has mist entrainment, the compressor has serious surge and even stops.

[0268] The content of the impurity salt is large, the sodium chloride and sodium sulfate cannot meet the requirements of the national standards, and hazardous waste is generated.

[0269] F - The ion removal is not sufficient, the content is greater than 50 ppm, which causes serious equipment corrosion and titanium metal corrosion.

[0270] The traditional process has very high energy consumption, and the treatment cost per ton of water is high.

[0271] Therefore, as Figures 26-28 indicated, the present application provides a device coal chemical wastewater treatment method, comprising:

[0272] The wastewater is pretreated to remove oil impurities and solid impurities in the wastewater, to obtain wastewater A;

[0273] The wastewater A is introduced into the first electrochemical precipitator 1 for treatment to remove volatile phenol, SCN - , CN － , S 2- , F － , heterocyclic, polycyclic aromatic hydrocarbon COD, oil and color in the wastewater A, to obtain wastewater B;

[0274] The wastewater B is introduced into the hydrolysis acidification reactor 2 for treatment, to hydrolyze the first type of molecular organic matter in the wastewater B into the second type of molecular organic matter, to obtain wastewater C, the diameter of the first type of molecular organic matter being greater than that of the second type of molecular organic matter;

[0275] The wastewater C is introduced into the nitration-denitrification integrated reactor 3 for treatment to remove part of the COD in the wastewater C and to perform denitrification treatment on the wastewater C, to obtain wastewater D;

[0276] The wastewater D is introduced into the second electrochemical precipitator 5 for treatment to remove hardness, heavy metal impurities and residual COD of the wastewater D, to obtain wastewater E;

[0277] The wastewater E is subjected to desalination treatment.

[0278] In the embodiment of the present application, the desalination treatment comprises:

[0279] The wastewater E is introduced into the first-stage RO device 401, the NF device 402, the first-stage RO device 401 and the bipolar membrane electrodialysis device 404 in sequence for treatment.

[0280] In the embodiment of the present application, after the wastewater is introduced into the NF device 402 for reaction, it is introduced into the sulfate-reducing bacteria SRB digestion reactor and the second electrochemical precipitator 5 in sequence for treatment.

[0281] The various advantages of the device coal chemical wastewater treatment method provided by the present application can be mutually referred to and adapted to the device coal chemical wastewater treatment system described in the above embodiment, which will not be described here again.

[0282] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A device-based coal chemical wastewater treatment system, characterized in that, The pretreatment module, the first electrochemical precipitator, the hydrolysis acidification reactor, the nitration-denitrification integrated reactor and the desalination module are sequentially connected. The pretreatment module is used for removing oil impurities and solid impurities in the wastewater. The first electrochemical precipitator is used for removing at least one of volatile phenol, SCN - , CN － , S 2- , F － , heterocyclic, polycyclic aromatic hydrocarbon COD, oil, colority in wastewater The hydrolysis acidification reactor is used for hydrolyzing first type of molecular organic matters in the wastewater into second type of molecular organic matters, the first type of molecular organic matters having a larger diameter than the second type of molecular organic matters. The nitration-denitrification integrated reactor is used for removing part of COD in the wastewater and performing denitrification treatment on the wastewater. The desalination module is used for performing desalination treatment on the wastewater. The first electrochemical precipitator comprises: An electrochemical reaction tank, a water inlet assembly, an electrode assembly and a water collection assembly are sequentially arranged in a tank body of the electrochemical reaction tank, the electrode assembly is arranged in multiple groups and is distributed between the water inlet assembly and the water collection assembly, the electrode assembly comprises an anode and a cathode, the anode comprises first anode filler, the first anode filler comprises γ-FeOOH, FeO, FeCO3, Al, VO, CuO, protocatechuic acid and hydrothermal carbon, the cathode comprises a carbon nano-RVC blowing fluidized electrode, and the water collection assembly is used for collecting wastewater after electrochemical reaction. A flocculation and precipitation tank, a flocculation reaction unit, a first precipitation unit and a first drainage unit are sequentially and communicatively arranged in a tank body of the flocculation and precipitation tank, the flocculation reaction unit is communicated with the water collection assembly, the flocculation reaction unit is used for adding a coagulant aid to generate a flocculation reaction, and the precipitation unit is used for precipitating and separating wastewater after the flocculation reaction. A sludge discharge assembly is arranged at the bottom of the electrochemical reaction tank and the flocculation and precipitation tank respectively, and is used for discharging sludge in the wastewater. The anode is an anode plate, the anode plate has a reverse trapezoidal bending structure which is sequentially connected, a plurality of water outlets are uniformly arranged on the anode plate, the cathode has a tubular structure, the cathode is located in the trapezoidal bending structure, and the cathode and three surfaces of the trapezoidal bending structure are spaced apart.

2. The apparatus-based coal combustion wastewater treatment system of claim 1, wherein, The hydrolysis acidification reactor comprises: A first main tank body, a first water inlet unit, a hydrolysis acidification zone, a second precipitation unit and a second drainage unit are sequentially arranged in the first main tank body from bottom to top, the hydrolysis acidification zone contains microorganisms to perform a hydrolysis acidification reaction on wastewater, and the precipitation unit is used for precipitating and separating wastewater after the hydrolysis acidification reaction. A dissolved oxygen adjusting unit, the dissolved oxygen adjusting unit comprises a second water inlet pipe and a first water outlet pipe, the second water inlet pipe is communicated with the hydrolysis acidification zone, the first water outlet pipe is communicated with the first water inlet unit, and the dissolved oxygen adjusting unit is used for adjusting the oxygen content in the wastewater. A first control valve, the first control valve is arranged on the first water outlet pipe and is used for controlling the flow of the first water outlet pipe. A sludge discharge unit, the sludge discharge unit is arranged at the bottom of the first main tank body and is used for discharging sludge in the wastewater.

3. The apparatus-based coal combustion wastewater treatment system of claim 1, wherein, The nitration-denitrification integrated reactor comprises: A second main tank body, a second water inlet unit, an anaerobic zone, an aerobic zone, an anoxic zone and a third drainage unit are sequentially arranged in the second main tank body from bottom to top. The anaerobic zone contains microorganisms for ammonification of wastewater, an aeration assembly is arranged between the anaerobic zone and the aerobic zone, the aeration assembly aerates the aerobic zone, the aerobic zone contains nitrifying bacteria filler for nitrification of the wastewater subjected to ammonification, the anoxic zone contains denitrifying bacteria filler for denitrification of the wastewater subjected to nitrification, a filter plate is arranged between the aerobic zone and the anoxic zone, the filter plate filters the wastewater flowing from the aerobic zone to the anoxic zone to prevent the fillers in the aerobic zone and the anoxic zone from flowing into each other, and the center of the anoxic zone is divided into a third sedimentation unit for sedimentation and separation of the wastewater subjected to denitrification, and a third water discharge unit for discharging the wastewater subjected to sedimentation and separation; a reflux unit, the reflux unit includes a water inlet end and a water outlet end, the water inlet end is in communication with the anoxic zone, and the water outlet end is in communication with the second water inlet unit, the reflux unit is used to reflux the wastewater in the anoxic zone to the second water inlet unit; a second control valve, the second control valve is arranged at the water outlet end of the reflux unit, and is used to control the water outlet amount of the reflux unit.

4. The apparatus-based coal combustion wastewater treatment system of claim 1, wherein, The nitrification-denitrification integrated reactor and the desalination module are provided with a second electrochemical precipitator, which is used to reduce the hardness of the wastewater and remove heavy metal impurities and / or residual COD in the wastewater.

5. The apparatus-based coal combustion wastewater treatment system of claim 4, wherein, The desalination module and the second electrochemical precipitator are sequentially provided with a sedimentation device and a filtration device.

6. The apparatus for coalification wastewater treatment system of any one of claims 1-5, wherein, Further comprising a first sludge concentration and dehydration module and a second sludge concentration and dehydration module, the first sludge concentration and dehydration module includes a first sludge concentration tank and a first sludge dehydration tank connected in sequence, and the second sludge concentration and dehydration module includes a second sludge concentration tank and a second sludge dehydration tank connected in sequence; The first electrochemical precipitator, the hydrolysis acidification reactor and the nitrification-denitrification integrated reactor are respectively connected with the first sludge concentration tank, and the sedimentation device is connected with the second sludge concentration tank.

7. The apparatus for coalification wastewater treatment system of any one of claims 1-5, wherein, The desalination module includes a first RO device, an NF device, a second RO device and a bipolar membrane electrodialysis device connected in sequence.

8. A method for treating coal chemical wastewater by equipment, characterized in that, Based on the equipment coal chemical wastewater treatment system as claimed in any one of claims 1 to 7, comprising: The wastewater is pretreated to remove oil impurities and solid impurities in the wastewater to obtain wastewater A; The wastewater A is introduced into a first electrochemical precipitator for treatment to remove volatile phenol, SCN - , CN － , S 2- , F － , heterocyclic, polycyclic aromatic hydrocarbon COD, oil and color from the wastewater A to obtain wastewater B; The wastewater B is introduced into a hydrolysis acidification reactor for treatment, and first type of molecular organic matter in the wastewater B is hydrolyzed into second type of molecular organic matter to obtain wastewater C, the diameter of the first type of molecular organic matter is larger than that of the second type of molecular organic matter; The wastewater C is introduced into a nitrification-denitrification integrated reactor for treatment to remove part of COD in the wastewater C and to perform denitrification treatment on the wastewater C to obtain wastewater D; The wastewater D is introduced into a second electrochemical precipitator for treatment to remove hardness, heavy metal impurities and residual COD in the wastewater D to obtain wastewater E; The wastewater E is subjected to desalination treatment.

9. The apparatus for coal combustion wastewater treatment method according to claim 8, wherein, The desalination treatment comprises: The wastewater E is sequentially introduced into a first RO device, a NF device, a first RO device and a bipolar membrane electrodialysis device for treatment.

10. The apparatus for coal combustion wastewater treatment method according to claim 9, wherein, After the wastewater is introduced into the NF device for reaction, the wastewater containing sulfate is sequentially introduced into a sulfate-reducing bacteria (SRB) digestion reactor and the second electrochemical precipitator for treatment.

Images