CN110668620A - Jet Fluidized Bed Electro-Fenton Treatment System - Google Patents

Abstract

The invention discloses a jet fluidized bed type electro-Fenton treatment system, wherein the jet-flow drug addition, aeration and water distribution system introduces waste water and performs aeration treatment to form a gas-liquid mixed flow; the electro-Fenton treatment system performs electro-Fenton treatment The waste water is output to the precipitation effluent tank, and the waste gas is output to the gas collection and treatment system; the precipitation effluent tank precipitates the wastewater and discharges it to the filler recovery and preparation system; the filler recovery and preparation system adds the iron sludge recovered particles to the electro-Fenton treatment system; gas collection and treatment The system introduces part of the waste gas into the jet dosing aeration water distribution system for aeration treatment. Through the technical scheme of the present invention, the removal rate of electro-Fenton is greatly broken, so that the electro-Fenton method can achieve zero discharge of chemical sludge, and the method of fluidized bed also promotes chemical oxidation reaction and electro-mass transfer efficiency. Gas dosing creates a fluidized environment, saves energy and reduces consumption, greatly improves the removal rate, and the separated iron can be recycled.

Description

Jet Fluidized Bed Electro-Fenton Treatment System

technical field

The invention relates to the technical field of wastewater treatment, in particular to a jet fluidized bed type electro-Fenton treatment system.

Background technique

Electro-Fenton technology (E Fenton) is a new type of electrochemical advanced oxidation technology based on Fenton chemical reaction. Fenton needs the agent, the reaction principle is: 1) The oxygen dissolved in water produces hydrogen peroxide at the cathode (formula 1-1), which increases the COD degradation efficiency: 2) Add hydrogen peroxide in the tank, and the Fe ² electrolyzed by the anode iron plate ⁺ Constitutes Fenton's Reagent (Formula 1-2); 3) Fe ³⁺ can be reduced at the cathode to reduce subsequent iron sludge production (Formula 1-3). Electrodeton generates strong oxidizing hydroxyl radicals (·OH) in the reaction process, and utilizes the non-selective strong oxidizing power of ·OH to achieve the purpose of removing refractory organic pollutants. Electro-Fenton method can effectively reduce sludge production, and the treatment process is relatively clean; in addition, electro-Fenton method also has the advantages of relatively simple treatment equipment, high treatment efficiency, and small footprint.

At present, the widely used electro-Fenton adopts soluble iron anode plate and graphite electrode cathode plate. The Fenton reaction system is formed by adding hydrogen peroxide and aerating the cathode in the electrolytic cell to generate hydrogen peroxide. The reaction equation is as follows:

O ₂ +2e ^- +2H ⁺ →H ₂ O ₂ (E ⁰ =0.695V/SHE) (1-1)

H ₂ O ₂ +Fe ²⁺ →(Fe ³⁺ + ^- OH+·OH) (1-2)

Fe ³⁺ +e ^- →Fe ²⁺ (E ⁰ =0.77V/SHE) (1-3)

At present, the aeration systems of the widely used electro-Fenton treatment systems are mostly tubular aeration, and the generated air bubbles are large and difficult to attach to the cathode to participate in the reduction reaction. The ratio of hydrogen peroxide to anode Fe ²⁺ is limited, and it is difficult to further improve the ratio of hydrogen peroxide to anode Fe 2+; the electric mass transfer efficiency of the whole system is low, Fe ³⁺ is reduced to Fe ²⁺ very little, and the system will produce iron sludge.

SUMMARY OF THE INVENTION

In view of at least one of the above problems, the present invention provides a fluidized bed type electro-Fenton treatment system. By using the advantages of the fluidized bed carrier filler in the electro-Fenton technology, the electro-Fenton effluent system precipitates iron sludge It is used to prepare fluidized fillers, so that Fe ³⁺ can not only be reduced at the cathode, but also coat the surface of the fluidized filler support by crystallization or precipitation to form hydroxy complex iron, which can further catalyze the Fenton reaction and reduce it to Fe ²⁺ , which greatly breaks through the removal rate of electro-Fenton, making electro-Fenton method zero discharge for chemical sludge, and the fluidized bed method also promotes chemical oxidation reaction and electro-mass transfer efficiency. At the same time, it creates a fluidized environment, saves energy and reduces consumption, greatly improves the removal rate, and the separated iron can be recycled.

In order to achieve the above purpose, the present invention provides a jet fluidized bed type electro-Fenton treatment system, including: a jet dosing aeration water distribution system, an electro-Fenton treatment system, a sedimentation effluent pool, a filler recovery preparation system and a gas collection system The treatment system; the jet dosing aeration water distribution system introduces waste water, pumps hydrogen peroxide into the waste water, and inputs air to aerate the waste water to form a gas-liquid mixed flow, and the gas-liquid mixed flow is sprayed into the electric fen In the electro-Fenton treatment system; fluidized fillers are added to the electro-Fenton treatment system, the wastewater after dosing and aeration is treated by electro-Fenton, and the treated wastewater is output to the sedimentation tank, and the electro-Fenton The waste gas produced by the treatment is output to the gas collection and treatment system; the precipitation water tank performs alkali treatment and precipitation on the wastewater after electro-Fenton treatment, and discharges the precipitated sludge to the filler recovery and preparation system; the filler The recovery and preparation system is to recycle the particles after drying, adding viscose additives, granulation and calcination into the electro-Fenton treatment system as a fluidized filler; the gas collection treatment system introduces a part of the collected waste gas into the jet dosing In the aeration water distribution system, the wastewater is treated by aeration, and the rest is treated by combustion consumption.

In the above technical solution, preferably, the electro-Fenton treatment system includes a power source, an anode plate, a cathode plate and a Fenton reaction cell, and the anode plate and the cathode plate are respectively connected to the positive electrode and the negative electrode of the power source , the anode plate and the cathode plate are respectively arranged in the Fenton reaction cell at intervals and staggered.

In the above technical solution, preferably, the jet drug dosing aeration water distribution system includes a water suction pump, a hydrogen peroxide storage tank, a hydrogen peroxide dosing pump, a self-excited oscillating jet dosing mixer, an induced draft fan, a gas-liquid outlet pipeline, a Air-distributing water nozzle and fluidized packing; the inlet of the suction pump is input with waste water, the outlet of the suction pump is communicated with the self-excited oscillating jet dosing mixer, and the inlet of the hydrogen peroxide dosing pump is connected to the hydrogen peroxide The storage tank is communicated, the outlet of the hydrogen peroxide dosing pump is communicated with the outlet channel of the suction pump, the outlet of the induced draft fan is communicated with the suction pipe of the self-excited oscillating jet dosing mixer, and the The outlet of the self-excited oscillating jet dosing mixer is connected to the aeration and water distribution nozzles through the gas-liquid outlet line, and a plurality of the aeration and water distribution nozzles are arranged at the bottom of the Fenton reaction tank. The filler is filled in the Fenton reaction cell.

In the above technical solution, preferably, the self-excited oscillation jet dosing mixer includes a fluid-driven nozzle, the suction pipe, an air mixing chamber, a self-excited oscillation chamber, a collision wall and a diffusion pipe. The nozzle is communicated with the outlet of the suction pump and the hydrogen peroxide dosing pump, the air mixing chamber is arranged at the outlet of the fluid-driven nozzle, and the side wall of the air mixing chamber is communicated with the suction pipe, The gas inhaled by the suction pipe and the mixture of waste water and hydrogen peroxide form a gas-liquid mixed flow in the gas mixing chamber, and the self-excited oscillation chamber is provided at the outlet of the gas mixing chamber. The collision wall is formed inside, and the gas-liquid mixed flow is self-excited and sheared in the self-excited oscillation chamber to form a discrete vortex ring, and a pressure shock wave is generated under the action of the collision wall, and the self-excited oscillation chamber The outlet of the chamber is communicated with the diffusion pipe, the diffusion pipe is communicated with the gas-liquid outlet line, and the gas-liquid mixed flow is ejected from the diffusion pipe.

In the above technical solution, preferably, the sedimentation effluent tank includes a neutralization tank, an alkali addition subsystem, a sedimentation tank, an inclined plate sedimentation, a sludge scraper and a sludge discharge pipe, and the wastewater from the Fenton reaction tank is introduced into the In the neutralization tank, the alkali adding subsystem adds an alkaline reagent to the neutralization tank to carry out a neutralization reaction, and after the neutralization reaction, it enters the sedimentation tank, and the inclined plate precipitation is inclined and arranged in the sedimentation tank, The sedimented sludge settles to the bottom of the sedimentation tank with the inclined plate, and the sludge scraper outputs the sludge to the filler recovery and preparation system through the sludge discharge pipe, and the sludge discharge pipe is provided with Sludge valve.

In the above technical solution, preferably, the filler recovery and preparation system includes a dryer, a granulator, an auxiliary subsystem and a calciner, the inlet of the dryer is communicated with the mud discharge pipe, and the outlet of the dryer It is communicated with the inlet of the granulator, and the auxiliary subsystem adds viscose auxiliary to the granulator, and the dried sludge is formed into a bar under the action of the viscose auxiliary and granulated. Granule output, the outlet of the granulator is communicated with the calciner, the outlet of the calciner is communicated with the feeding hole on the Fenton reaction tank, and the calcined porous iron particles are recycled as the fluidized filler. used in the Fenton reaction tank.

In the above technical solution, preferably, the gas collection and treatment system includes a gas collecting hood, an air induction pipe and a combustion tower, the gas collecting hood sealing cover is provided on the Fenton reaction tank, and one end of the air induction pipe is connected to In the gas collecting hood, the other end is respectively connected to the inlet of the induced draft fan through a return valve and to the combustion tower through an electric valve.

In the above technical solution, preferably, the axial centerline of the aeration and water distribution nozzles intersects the horizontal plane downward at 30° to 60°, and a plurality of the aeration and water distribution nozzles are respectively surrounded by a preset ejection angle. It is arranged at the bottom of the Fenton reaction tank.

In the above technical solution, preferably, the current density of the anode plate is 0.25-12.5mA, the current density of the cathode plate is 2-15mA, and the concentration of Fe ²⁺ catalyst in the Fenton reaction cell is 0.2mol/ L～12mol/L, the concentration of hydrogen peroxide is 0.04mol/L～3mol/L, and the distance between the anode plate and the cathode plate is 15～40mm.

In the above technical solution, preferably, when the air source required by the return air pipe where the return valve is located is insufficient and the inside of the return air pipe is negative pressure, the electric valve is opened in the reverse direction to supplement the air source to the induced draft fan, the When there is positive pressure in the return gas pipe, the combustion tower is opened to consume the remaining exhaust gas.

Compared with the prior art, the beneficial effects of the present invention are: by using the advantages of the fluidized bed carrier filler in the electro-Fenton technology, the electro-Fenton effluent system precipitates iron sludge for preparing the fluidized filler, so that Fe ³⁺ not only It can be reduced at the cathode, and at the same time, it is coated on the surface of the fluidized filler support by crystallization or precipitation to form hydroxy complex iron, which can further catalyze the Fenton reaction and reduce it to Fe ²⁺ , which greatly breaks through the removal of electro-Fenton. The electro-Fenton method has zero discharge for chemical sludge, and the fluidized bed method also promotes chemical oxidation reaction and electric mass transfer efficiency, creating a fluidized environment while aeration and dosing, saving energy and reducing consumption. The removal rate is improved, and the separated iron can be recycled.

Description of drawings

1 is a schematic diagram of the overall structure of a jet fluidized bed electro-Fenton processing system disclosed in an embodiment of the present invention;

FIG. 2 is a schematic diagram of the combined structure of an electro-Fenton treatment system and a jet dosing aeration water distribution system disclosed in an embodiment of the present invention;

3 is a schematic structural diagram of an electro-Fenton processing system disclosed in an embodiment of the present invention;

4 is a schematic cross-sectional structural diagram of a self-excited oscillating jet dosing mixer disclosed in an embodiment of the present invention;

5 and 6 are schematic diagrams of application modes of two embodiments of the Fenton reaction cell disclosed in the present invention.

In the figure, the corresponding relationship between each component and the reference sign is:

1. Electro-Fenton treatment system, 11. Power supply, 12. Anode plate, 13. Cathode plate, 14. Fenton reaction cell,

2. Jet dosing and aeration water distribution system, 21. Diversion pump, 22. Hydrogen peroxide storage tank, 23. Hydrogen peroxide dosing pump, 24. Self-excited oscillating jet dosing mixer, 241. Fluid driven nozzle, 242. Inhalation Pipe, 243. Mixing chamber, 244. Self-excited oscillation chamber, 245. Collision wall, 246. Diffusion pipe, 25. Induced draft fan, 26. Gas-liquid outlet pipeline, 27. Aeration water distribution nozzle, 28. Fluidization filler,

3. Sedimentation tank, 31. Neutralization tank, 32. Alkali addition subsystem, 33. Sedimentation tank, 34. Inclined plate sedimentation, 35. Sludge scraper, 36. Sludge discharge valve, 37. Sludge discharge pipe,

4. Filler recovery preparation system, 41. Dryer, 42. Granulator, 43. Auxiliary subsystem, 44. Calciner, 45. Feeding hole,

5. Gas collection and processing system, 51. Gas collection hood, 52. Induction pipe, 53. Electric valve, 54. Return valve, 55. Return gas pipe, 56. Burning tower.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

Below in conjunction with accompanying drawing, the present invention is described in further detail:

As shown in FIG. 1 and FIG. 2 , a jet fluidized bed electro-Fenton treatment system provided according to the present invention includes: a jet dosing aeration water distribution system 2 , an electro-Fenton treatment system 1 , and a sedimentation water tank 3 , a filler recovery preparation system 4 and a gas collection and treatment system 5; the jet dosing aeration water distribution system 2 introduces waste water, pumps hydrogen peroxide into the waste water, and enters air to aerate the waste water to form a gas-liquid mixed flow, and the gas The liquid mixed flow is sprayed into the electro-Fenton treatment system 1; the fluidized filler 28 is added to the electro-Fenton treatment system 1, the wastewater after dosing and aeration is subjected to electro-Fenton treatment, and the treated wastewater is output to sedimentation Outlet tank 3, the waste gas produced by the electro-Fenton treatment is output to the gas collection and treatment system 5; the sedimentation tank 3 performs alkali treatment and precipitation on the wastewater after the electro-Fenton treatment, and discharges the precipitated sludge to the filler recovery preparation system 4 ; The filler recovery preparation system 4 is added to the electro-Fenton treatment system 1 as a fluidized filler 28 by drying, adding viscose additives, granulating and calcining the particles; In the aeration water distribution system 2, aeration treatment is performed on the wastewater, and the rest is subjected to combustion consumption treatment.

In this embodiment, the industrial wastewater enters the electro-Fenton treatment system 1 through the jet medicated aeration water distribution system 2, and hydrogen peroxide (hydrogen peroxide) is pumped into the jet medicated aeration water distribution system 2, and the gas used in the system The fluidized filler 28 is added into the electro-Fenton treatment system 1 to realize fluidization. The effluent of the electro-Fenton treatment system 1 enters the sedimentation effluent tank 3 for neutralization and precipitation, and the iron sludge at the bottom of the tank enters the filler recovery and preparation system 4. Drying, granulating and calcining are carried out to obtain the fluidized filler 28 required by the electro-Fenton treatment system 1 for recycling. The exhaust gas generated by the electro-Fenton treatment system 1 is recovered and processed by the gas collection and treatment device, and a part of the exhaust gas is used to supply air to the jet dosing, aeration, and water distribution system 2, and the excess gas is burned and consumed.

Specifically, by using the advantages of the fluidized bed support filler in the electro-Fenton technology, the electro-Fenton effluent system precipitates iron sludge for the preparation of the fluidized filler 28, so that Fe ³⁺ can not only be reduced at the cathode, but also crystallized or The precipitation is coated on the surface of the fluidized filler 28 to form hydroxy complex iron, which can further catalyze the Fenton reaction and reduce it to Fe ²⁺ , which greatly breaks through the removal rate of electro-Fenton and makes electro-Fenton method for chemical Zero discharge of sludge, and the fluidized bed method also promotes chemical oxidation reaction and electrical mass transfer efficiency, creating a fluidized environment while aeration and dosing, saving energy and reducing consumption, greatly improving the removal rate, and the separated Iron is recycled.

As shown in FIG. 3 , in the above embodiment, preferably, the electro-Fenton processing system 1 includes a power source 11 , an anode plate 12 , a cathode plate 13 and a Fenton reaction cell 14 , and the anode plate 12 and the cathode plate 13 are respectively connected to the power source 11 . The positive electrode and the negative electrode are connected to each other, and the anode plate 12 and the cathode plate 13 are respectively arranged in the Fenton reaction cell 14 in a spaced dislocation.

In the above embodiment, preferably, the pH value of the industrial wastewater influent is adjusted to 3-6, and the micron-scale gas-liquid mixed flow is injected into the electro-Fenton treatment system 1 through the jet dosing and aeration water distribution system 2, and the two ports are opened. The DC power supply 11 controls the current density of the anode plate 12 to be 0.25-12.5mA, the current density of the cathode plate 13 is 2-15mA, and the hydraulic retention time is controlled to be 30min-480min, and the organic wastewater treatment is completed. The concentration of Fe ²⁺ catalyst in the Fenton reaction tank 14 is controlled to be 0.2 mol/L to 12 mol/L, and the concentration of hydrogen peroxide is 0.04 mol/L to 3 mol/L. Preferably, the iron electrode anode plate 12 and the graphite electrode cathode plate 13 are placed near the oxygen evolution electrode, and the distance between the iron electrode anode plate 12 and the graphite electrode cathode plate 13 is preferably 15-40 mm. Under the action of the current, the iron electrode and the graphite electrode undergo a two-electron reaction at the same time, the iron electrode generates Fe ²⁺ , the graphite electrode receives the oxygen generated by the oxygen evolution electrode to generate a small amount of H ₂ 0 ₂ , and the Fe ²⁺ reacts with the in-situ generated and pumped H ₂ O ₂ reacts to generate OH with strong oxidizing properties, thereby oxidizing and removing organic pollutants.

In the above-mentioned embodiment, preferably, the jet drug dosing aeration water distribution system 2 includes a suction pump 21, a hydrogen peroxide storage tank 22, a hydrogen peroxide dosing pump 23, a self-excited oscillating jet dosing mixer 24, an induced draft fan 25, a gas-liquid The outlet pipeline 26, the aeration water distribution nozzle 27 and the fluidized packing 28; the inlet of the suction pump 21 inputs waste water, the outlet of the suction pump 21 is communicated with the self-excited oscillating jet dosing mixer 24, and the inlet of the hydrogen peroxide dosing pump 23 is connected to the The hydrogen peroxide storage tank 22 is communicated, the outlet of the hydrogen peroxide dosing pump 23 is communicated with the outlet channel of the suction pump 21, the outlet of the induced draft fan 25 is communicated with the suction pipe 242 of the self-excited oscillating jet dosing mixer 24, and the self-oscillating The outlet of the jet dosing mixer 24 is connected to the aeration and water distribution nozzles 27 through the gas-liquid outlet line 26. A plurality of aeration and water distribution nozzles 27 are arranged at the bottom of the Fenton reaction tank 14, and the fluidized filler 28 is filled in the Fenton reaction. Inside pool 14.

As shown in FIG. 4 , in the above embodiment, preferably, the self-excited oscillation jet dosing mixer 24 includes a fluid-driven nozzle 241 , a suction pipe 242 , a gas mixing chamber 243 , a self-excited oscillation chamber 244 , and a collision wall 245 And the diffusion pipe 246, the fluid-driven nozzle 241 is communicated with the outlet of the suction pump 21 and the hydrogen peroxide dosing pump 23, the outlet of the fluid-driven nozzle 241 is provided with an air mixing chamber 243, and the side wall of the air mixing chamber 243 is connected with the suction pipe 242 The gas is inhaled by the suction pipe 242 and the mixture of waste water and hydrogen peroxide forms a gas-liquid mixed flow in the gas mixing chamber 243. A self-excited oscillation chamber 244 is arranged at the outlet of the gas mixing chamber 243, and the interior of the self-excited oscillation chamber 244 forms a collision Wall 245, the gas-liquid mixed flow is self-excited and sheared in the self-excited oscillation chamber 244 to form discrete vortex rings, and pressure shock waves are generated under the action of the collision wall 245, and the outlet of the self-excited oscillation chamber 244 is connected to the diffusion pipe 246 , the diffusion pipe 246 is communicated with the gas-liquid outlet pipeline 26 , and the gas-liquid mixed flow is ejected from the diffusion pipe 246 .

Specifically, the industrial wastewater is introduced into the self-excited oscillating jet dosing mixer 24 by the suction pump 21, and after adding a certain amount of hydrogen peroxide by the hydrogen peroxide dosing pump 23, it is ejected through the fluid-driven nozzle 241 to form a negative pressure in the air mixing chamber 243, Part of the exhaust gas of the gas collection and processing system 5 is sucked in by the suction pipe 242, and the induced draft fan 25 plays the role of pulling the exhaust gas. The gas-liquid mixed flow is perturbed by vorticity within a certain frequency range in the self-excited oscillation chamber 244, and is amplified in the self-excited oscillation chamber 244, and a severe shear field is formed by the self-excited oscillation, and the shear layer A series of discrete vortex rings are formed in the collision wall 245, when they reach the collision wall 245 and interact with it, a pressure oscillation wave will be generated in the area near the collision wall 245, which propagates upstream at the speed of sound, and induces new upstream vorticity pulsations. . If the process is repeated continuously, a strong self-excited oscillation will be formed in the chamber. After a certain number of cycles, the gas-liquid mixture flowing through the self-excited oscillation chamber will be repeatedly and violently sheared to reduce the size of the generated bubbles, and to achieve The uniform mixing of raw water and hydrogen peroxide produces micron-sized bubbles. The gas-liquid two-phase flow is ejected from the diffuser tube 246 in the form of pulses.

As shown in FIG. 5 and FIG. 6 , specifically, the gas-liquid mixed flow is introduced into the electro-Fenton treatment system 1 through the gas-liquid outlet line 26, and further air and water distribution is performed through several aeration and water distribution nozzles 27, and fluidization is realized. Fluidized state of packing 28. Preferably, a plurality of aeration water distribution nozzles 27 are arranged around the bottom of the Fenton reaction tank 14 of the electro-Fenton treatment system 1 at a preset injection angle. Further preferably, the axial centerline of the aeration and water distribution nozzles 27 intersects the horizontal plane downward at 30° to 60°, and the combined arrangement of several aeration and water distribution nozzles 27 controls the flow state of the fluid in the Fenton reactor. , which can further realize the uniformity of air distribution and water distribution, realize the fluidization state without dead angle, and improve the efficiency of electric mass transfer.

Specifically, as shown in FIG. 5 , if the Fenton reaction tank 14 is circular, the gas-liquid exit line 26 is also circular, surrounding the inner bottom circumference edge of the circular Fenton reaction tank 14, and the aeration and water distribution nozzles 27 They are evenly arranged on the gas-liquid outlet line 26 at a preset interval. Since the anode plate 12 and the cathode plate 13 of the electro-Fenton treatment system 1 are also arranged at the bottom of the Fenton reaction cell 14, the anode plate 12 and the cathode plate are 13 are arranged along the diameter direction of the circular Fenton reaction tank 14, and the aeration and water distribution nozzles 27 are respectively arranged on the circumference of the gas-liquid outlet pipeline 26, and are directed towards a preset ejection angle direction relative to the tangential direction of the current position. In this way, under the arrangement of the aeration and water distribution nozzles 27 that surround the whole Fenton reaction tank 14, there are jet streams in all directions, and the axial centerline and the horizontal plane intersect downward at 30° to 60°, so that the The fluidized packing in the Fenton reaction tank 14 is in a fluidized state and can be fully mixed under the impact of the liquid column ejected from the aeration water distribution nozzle 27 . The agitation and mixing of the fluid happens mainly in the regions of the anode plate 12 and the cathode plate 13 where the reaction is performed, so as to realize a fluidized state without dead angle and improve the electric mass transfer efficiency of the Fenton reaction.

As shown in FIG. 6 , if the Fenton reaction tank 14 is rectangular or square, the gas-liquid outlet line 26 is also rectangular or square, and is arranged on the edge of the tank wall at the bottom of the Fenton reaction tank 14, and the aeration water distribution nozzles 27 are respectively It is evenly arranged on the gas-liquid outlet line 26 at a preset interval. Since the anode plate 12 and the cathode plate 13 of the electro-Fenton treatment system 1 are also arranged at the bottom of the Fenton reaction cell 14, the anode plate 12 and the cathode plate 13 Horizontally arranged in the middle of the rectangular or square Fenton reaction tank 14, the aeration and water distribution nozzles 27 are respectively arranged on the gas-liquid outlet pipelines 26 of each section along the direction of the pool wall, and are directed towards a preset relative to the current position of the pool wall direction. In this way, under the arrangement of the surrounding aeration water distribution nozzles 27, the entire Fenton reaction tank 14 has jet streams in all directions, and its axial centerline intersects the horizontal plane downward at a distance of 30° to 60°. °, so that the fluidized packing in the Fenton reaction tank 14 is in a fluidized state, and can be fully mixed under the impact of the liquid column ejected from the aeration water distribution nozzle 27 . The agitation and mixing of the fluid happens mainly in the regions of the anode plate 12 and the cathode plate 13 where the reaction is carried out in the middle, so as to achieve a fluidized state without dead ends and improve the electric mass transfer efficiency of the Fenton reaction.

Among them, the jet dosing aeration water distribution system 2 makes the fluidized packing 28 in the Fenton reaction tank 14 in a multi-dimensional longitudinal and annular flow, and the complex iron produced by the electro-Fenton reaction is crystallized or precipitated. Coated with the surface of the fluidized bed packing to form a support, so that most of the Fe ³⁺ produced by the reaction grows on the packing to form FeOOH heterogeneous crystals, which are also a good catalyst and promote Fe on the surface of the support. The conversion of ³⁺ to Fe ²⁺ , due to the existence of Fe carrier in the reaction pool, also increases the electrical conductivity, forming a micro-battery structure, providing catalytic action and reaction site for the action of OH free radicals and COD, improving sewage and The contact frequency between OH radicals, and at the same time, there is no dead angle in the electro-Fenton reaction zone, which provides space for further increasing the concentration of Fenton reagents, low energy consumption, and high efficiency.

In the above embodiment, preferably, the sedimentation tank 3 includes a neutralization tank 31, an alkali addition subsystem 32, a sedimentation tank 33, an inclined plate sedimentation 34, a sludge scraper 35 and a sludge outlet pipe 37. The waste water is introduced into the neutralization tank 31, and the alkali addition subsystem 32 adds an alkaline reagent to the neutralization tank 31 for neutralization reaction, and the pH value is controlled to be 7-7.5. After the neutralization reaction, it enters the sedimentation tank 33, the inclined plate sedimentation 34 is inclined and arranged in the sedimentation tank 33, and the sedimented sludge settles with the inclined plate sedimentation 34 to the bottom of the sedimentation tank 33 to realize the separation of mud and water, and the supernatant is discharged for further processing, The sludge scraper 35 outputs the sludge to the filler recovery preparation system 4 through the sludge discharge pipe 37 , and the sludge discharge pipe 37 is provided with a sludge discharge valve 36 .

In the above embodiment, preferably, the filler recovery preparation system 4 includes a dryer 41, a granulator 42, an auxiliary subsystem 43 and a calciner 44, the inlet of the dryer 41 is communicated with the mud discharge pipe 37, and the outlet of the dryer 41 is connected Connected with the inlet of the granulator 42, the auxiliary subsystem 43 adds the viscose auxiliary agent into the granulator 42, and the dried sludge is formed into a bar material under the action of the viscose auxiliary agent and granulated for output. The outlet of the machine 42 is communicated with the calciner 44, and the outlet of the calciner 44 is communicated with the feeding hole 45 on the Fenton reaction tank 14, and the calcined porous iron particles are periodically recycled to the Fenton reaction tank 14 as the fluidized filler 28 for recovery. use.

In the above embodiment, preferably, the gas collection and treatment system 5 includes a gas collecting hood 51, an air induction pipe 52 and a combustion tower 56, the gas collecting hood 51 is sealed and provided on the Fenton reaction cell 14, and one end of the air induction pipe 52 is connected to each other. In the gas collecting hood 51 , the other end is connected to the inlet of the induced draft fan 25 through the return valve 54 and the combustion tower 56 through the electric valve 53 , respectively.

In the above-mentioned embodiment, preferably, when the air source required by the return air pipe 55 where the return valve 54 is located is insufficient and the negative pressure in the return air pipe 55, the electric valve 53 is opened in the reverse direction to supplement the air source to the induced draft fan 25, and the return air pipe 55 is At positive pressure, the combustion tower 56 is opened to consume the remaining exhaust gas.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A jet fluidized bed electro-fenton treatment system, comprising: the system comprises a jet flow dosing aeration water distribution system, an electro-Fenton treatment system, a sedimentation water outlet pool, a filler recovery preparation system and a gas collection treatment system;

the jet flow dosing aeration water distribution system introduces wastewater, hydrogen peroxide is pumped into the wastewater, air is input to carry out aeration treatment on the wastewater to form gas-liquid mixed flow, and the gas-liquid mixed flow is sprayed into the electro-Fenton treatment system;

adding a fluidized filler into the electro-Fenton treatment system, performing electro-Fenton treatment on the wastewater after adding the chemicals and aerating, outputting the treated wastewater to the sedimentation water outlet tank, and outputting waste gas generated by the electro-Fenton treatment to the gas collection treatment system;

the sedimentation water outlet tank is used for carrying out alkali treatment and sedimentation on the wastewater after electro-Fenton treatment, and discharging the precipitated sludge to the filler recovery preparation system;

the filler recovery preparation system circularly adds the particles after drying, adding the viscose auxiliary agent and granulating and calcining into the electro-Fenton treatment system to serve as fluidized fillers;

the gas collecting and processing system introduces a part of the collected waste gas into the jet flow dosing aeration water distribution system to carry out aeration treatment on the waste water, and the rest part is subjected to combustion consumption treatment.

2. The jet fluidized bed electro-Fenton treatment system according to claim 1, comprising a power source, an anode plate, a cathode plate and a Fenton reaction tank, wherein the anode plate and the cathode plate are respectively connected with a positive pole and a negative pole of the power source, and the anode plate and the cathode plate are respectively arranged in the Fenton reaction tank at intervals in a staggered manner.

3. The jet fluidized bed electro-fenton treatment system of claim 1, wherein: the jet medicine adding aeration water distribution system comprises a water diversion pump, a hydrogen peroxide storage tank, a hydrogen peroxide medicine adding pump, a self-oscillation jet medicine adding mixer, a draught fan, a gas-liquid outgoing pipeline, an aeration water distribution nozzle and fluidized fillers;

waste water is input at the inlet of the diversion pump, the outlet of the diversion pump is communicated with the self-oscillation jet-flow dosing mixer, the inlet of the hydrogen peroxide dosing pump is communicated with the hydrogen peroxide storage tank, the outlet of the hydrogen peroxide dosing pump is communicated with the outlet channel of the diversion pump, the outlet of the induced draft fan is communicated with the air suction pipe of the self-oscillation jet-flow dosing mixer, the outlet of the self-oscillation jet-flow dosing mixer is connected to the aeration water distribution nozzle through a gas-liquid outgoing pipeline, the aeration water distribution nozzle is arranged at the bottom in the Fenton reaction tank, and the fluidization filler is filled in the Fenton reaction tank.

4. The jet fluidized bed electro-Fenton treatment system according to claim 3, wherein the self-oscillating jet chemical dosing mixer comprises a fluid driving nozzle, the air suction pipe, a gas mixing chamber, a self-oscillating chamber, a collision wall and a diffusion pipe, the fluid driving nozzle is communicated with the water suction pump and the outlet of the hydrogen peroxide chemical dosing pump, the gas mixing chamber is arranged at the outlet of the fluid driving nozzle, the side wall of the gas mixing chamber is communicated with the air suction pipe, the mixture of the suction gas, the wastewater and the hydrogen peroxide forms a gas-liquid mixed flow in the gas mixing chamber, the self-oscillating chamber is arranged at the outlet of the gas mixing chamber, the collision wall is formed inside the self-oscillating chamber, the gas-liquid mixed flow self-oscillates and shears in the self-oscillating chamber to form a discrete vortex ring, and pressure oscillation waves are generated under the action of the collision wall, the outlet of the self-oscillation chamber is communicated with the diffusion pipe, the diffusion pipe is communicated with the gas-liquid outgoing pipeline, and the gas-liquid mixed flow is sprayed out from the diffusion pipe.

5. The jet fluidized bed electro-Fenton treatment system according to claim 1, wherein the precipitation effluent tank comprises a neutralization tank, an alkalifying subsystem, a sedimentation tank, an inclined plate sedimentation, a mud scraper and a mud outlet pipe, the wastewater in the Fenton reaction tank is introduced into the neutralization tank, the alkalifying subsystem adds an alkaline reagent into the neutralization tank for neutralization reaction, the wastewater enters the sedimentation tank after the neutralization reaction, the inclined plate sedimentation is obliquely arranged in the sedimentation tank, the precipitated sludge is sedimentated to the bottom of the sedimentation tank along with the inclined plate sedimentation, the mud scraper outputs the sludge to the filler recovery preparation system through the mud outlet pipe, and the mud outlet pipe is provided with a mud discharge valve.

6. The jet fluidized bed electro-Fenton treatment system according to claim 5, wherein the filler recovery preparation system comprises a dryer, a granulator, an auxiliary subsystem and a calciner, an inlet of the dryer is communicated with the sludge outlet pipe, an outlet of the dryer is communicated with an inlet of the granulator, the auxiliary subsystem adds a viscose auxiliary agent into the granulator, dried sludge is formed into bars under the action of the viscose auxiliary agent and output in a granulation mode, an outlet of the granulator is communicated with the calciner, an outlet of the calciner is communicated with a feeding hole in the Fenton reaction tank, and calcined porous iron particles are recycled to the Fenton reaction tank as the fluidized filler.

7. The fluid-jet fluidized-bed electro-Fenton treatment system according to claim 1, wherein the gas collection treatment system comprises a gas collection hood, an air induction pipe and a combustion tower, the gas collection hood is hermetically covered on the Fenton reaction tank, one end of the air induction pipe is communicated with the inside of the gas collection hood, and the other end of the air induction pipe is respectively connected to an inlet of the induced draft fan through a reflux valve and is communicated to the combustion tower through an electric valve.

8. The jet fluidized bed electro-Fenton treatment system according to claim 3, wherein the axial center line of the aeration water distribution nozzles intersects the horizontal surface downward at an angle of 30 ° to 60 °, and the plurality of aeration water distribution nozzles are circumferentially arranged at the bottom of the Fenton reaction tank at a predetermined angle of incidence, respectively.

9. The jet fluidized bed electro-Fenton treatment system according to claim 2, wherein the current density of the anode plate is 0.25-12.5 mA, the current density of the cathode plate is 2-15 mA, and Fe in the Fenton reaction tank²⁺The concentration of the catalyst is 0.2-12 mol/L, the concentration of hydrogen peroxide is 0.04-3 mol/L, and the distance between the anode plate and the cathode plate is 15-40 mm.

10. The fluid-jet fluidized-bed electro-fenton treatment system according to claim 7, wherein the electric valve is reversely opened to supplement the air source to the induced draft fan when the air source required by the return air pipe in which the return valve is located is insufficient and the pressure in the return air pipe is negative, and the combustion tower is opened to consume the remaining tail gas when the pressure in the return air pipe is positive.

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