CN210393837U

CN210393837U - Fenton oxidation reaction processing apparatus

Info

Publication number: CN210393837U
Application number: CN201920974539.5U
Authority: CN
Inventors: 刘润
Original assignee: Nanjing Runke Environment Co ltd
Current assignee: Nanjing Runke Environment Co ltd
Priority date: 2019-06-26
Filing date: 2019-06-26
Publication date: 2020-04-24
Anticipated expiration: 2029-06-26

Abstract

The utility model relates to a fenton oxidation reaction processing apparatus, including reactor body, inlet tube and outlet pipe, be equipped with waste water oxidation mechanism and waste water collection mechanism in the reactor body, waste water oxidation mechanism sets up the top at waste water collection mechanism, waste water oxidation mechanism passes through the mud pipe and links to each other with waste water collection mechanism, waste water oxidation mechanism includes electro-catalysis district, electro-catalysis reaction district and the play pool that sets gradually from left to right, be linked together in proper order between electro-catalysis district, electro-catalysis reaction district and the play pool, the inlet tube links to each other with electro-catalysis district, the play pool links to each other with the outlet pipe, the outlet pipe passes through the back flow and links to each other with the inlet tube; the utility model discloses with the combination use of electrocatalytic oxidation and fenton oxidation technology, utilize the effective space of reactor to the utmost extent, simplified the process flow of fenton oxidation preliminary treatment, reduced the running cost.

Description

Fenton oxidation reaction processing apparatus

Technical Field

The utility model relates to a fenton oxidation reaction processing apparatus belongs to sewage treatment technical field.

Background

The micro-electrolysis technology and the Fenton oxidation technology are two typical chemical wastewater pretreatment technologies, and are often adopted in the chemical wastewater treatment process design respectively or simultaneously, so that a better treatment effect can be achieved. Meanwhile, when the micro-electrolysis technology and the Fenton oxidation technology are adopted, the micro-electrolysis reaction device and the Fenton oxidation reaction device are usually connected in series, so that the aims of reducing the biological toxicity of the wastewater and improving the biodegradability of the wastewater are fulfilled, and good conditions are created for subsequent biochemical treatment. However, the design mode of serial use needs to connect the respective independent microelectrolysis and fenton oxidation reaction devices according to a set flow, and configure a series of auxiliary pipelines and facilities, and the simple superposed connection mode has high operation cost, long and complicated treatment process flow and high control requirement, and is difficult to make the zero-valent iron reduction reactor and the fenton oxidation reaction device in the optimal operation condition at the same time. In addition, the traditional Fenton method has some defects, such as large iron mud production amount, serious iron ion loss and low iron ion utilization efficiency; the Fenton iron mud produced by the Fenton process belongs to dangerous solid waste, the subsequent treatment cost is high, and enterprises are difficult to bear.

And nitrogen-containing heterocyclic compounds such as pyridine, pyrrole, indole, quinoline and derivatives thereof. Is widely used in the wastewater discharged by petrochemical industry, food industry, pesticide industry and the like. The water solubility of the nitrogen-containing heterocyclic compound is far greater than that of the homocyclic compound, the nitrogen-containing heterocyclic compound is easy to migrate in the soil environment to pollute underground water after entering the environment, and in addition, many nitrogen-containing heterocyclic compounds have toxicity, mutagenicity and carcinogenicity to animals and human beings and are difficult to degrade by natural microorganisms, so that potential and long-term harm is generated to the ecological system and human health, and therefore, the nitrogen-containing heterocyclic compound wastewater needs to be treated in a targeted manner. The wastewater has the characteristics of high salt content, high toxicity, poor biodegradability and complex components, and the conventional biological treatment cannot be independently performed, so that the problems of sludge poisoning, influence on the normal operation of a system and the like are easily caused. Therefore, it is urgently needed to develop a novel economic and efficient pretreatment process, so as to reduce the toxicity of the wastewater, improve the biodegradability and create good treatment conditions for the subsequent biochemical process. Recent researches show that the microelectrolysis-Fenton coupling technology is a feasible way for realizing the high-efficiency treatment of the wastewater containing the nitrogen heterocyclic compound. However, excessive ferrous sulfate and hydrogen peroxide are required to be added in the Fenton section, and the practical engineering application of the micro-electrolysis-Fenton coupling technology is severely limited by the defects of high cost of added medicament, large secondary pollution and the like. How to reduce the dosage of ferrous ions and the added hydrogen peroxide, improve the efficiency of Fenton reaction and reduce the generation amount of iron mud is a technical problem which needs to be overcome by the micro-electrolysis-Fenton combined process.

SUMMERY OF THE UTILITY MODEL

The utility model provides an oxidation composite set is oxidized with narrow passageway bipolar electrode coupling to electro-catalytic fenton oxidation realizes the oxidation preliminary treatment process that contains nitrogen heterocyclic in composite set to utilize the normal position production effect of ferrous iron to improve the catalytic performance of iron, recycle the negative pole reduction among the narrow passageway bipolar reaction device and reduce ferric iron into ferrous iron, improve the utilization efficiency of iron, thereby reduce iron mud formation volume by a wide margin, improve the treatment effeciency of nitrogenous heterocyclic waste water.

In order to achieve the above object, the utility model adopts the following technical scheme:

the utility model provides a fenton oxidation reaction processing apparatus, includes electro-catalytic fenton oxidation reactor, tubular reactor, inlet tube and outlet pipe, electro-catalytic fenton oxidation reactor links to each other with tubular reactor, electro-catalytic fenton oxidation reactor includes waste water oxidation mechanism and waste water collection mechanism, waste water oxidation mechanism sets up the top at waste water collection mechanism, waste water oxidation mechanism lower extreme links to each other with waste water collection mechanism through mud pipe, waste water oxidation mechanism includes electro-catalytic zone, reaction zone and the pool that sets gradually from left to right, be linked together in proper order between electro-catalytic zone, reaction zone and the pool, the inlet tube links to each other with the electro-catalytic zone, tubular reactor one end is passed through the outlet pipe and is linked to each other with the pool, the tubular reactor other end passes through the back flow and links to each other with the inlet tube.

As an improvement of the utility model, the electrocatalysis district includes first shell, water-locator, plate electrode, turns over baffle and insulating barrier, is equipped with two insulating barriers in the first shell, is equipped with the plate electrode between two insulating barriers, and two insulating barrier both ends link to each other with the inside and outside both sides of first shell respectively, the water-locator sets up in the top of plate electrode, turns over the baffle setting in the top of water-locator, and first shell left side links to each other with the inlet tube.

As an improvement of the utility model, be equipped with the sludge discharge pipe on the first shell, first shell passes through the sludge discharge pipe and links to each other with waste water collection mechanism.

As an improvement of the utility model, the electro-catalytic reaction zone comprises a second shell, a scraper and an overflow weir, the inner upper end of the second shell is provided with the scraper, and both sides of the scraper are provided with the overflow weir.

As an improvement of the utility model, the tubular reactor comprises electrode reactors, the quantity of electrode reactors is 2 at least, links to each other through the pipeline between two adjacent electrode reactors.

As an improvement of the utility model, the electrode reactor comprises an anode titanium flange, an anode titanium pipe, a water inlet, a water outlet, an anode binding post, a cathode titanium flange, a cathode titanium pipe and a cathode binding post; the lower end of one side of the anode titanium pipe is provided with a water inlet, the upper end of the other side of the anode titanium pipe is provided with a water outlet, the right side of the anode titanium pipe is provided with an anode wiring terminal, and the upper end of the anode titanium pipe is provided with an anode titanium flange; the bottom end of the cathode titanium pipe is sealed, the inner side of the anode titanium pipe is of a hollow structure, the cathode titanium pipe is arranged in the anode titanium pipe, a gap is arranged between the anode titanium pipe and the cathode titanium pipe, and a through hole corresponding to the cathode titanium pipe is arranged on the anode titanium flange; the cathode titanium tube upper end is equipped with cathode titanium flange and cathode terminal, and cathode terminal lower extreme links to each other with the cathode titanium tube, the cathode terminal upper end runs through the setting in cathode titanium flange.

As an improvement of the utility model, the second shell lower extreme is equipped with the mud pipe, the second shell passes through the mud pipe and links to each other with waste water collection mechanism.

As an improvement of the utility model, the water outlet mechanism comprises a third shell, and the right end of the third shell is connected with the water outlet pipe; and a sludge discharge pipe is arranged at the lower end of the third shell, and the third shell is connected with the wastewater collecting mechanism through the sludge discharge pipe.

As an improvement of the utility model, the number of the mud discharging pipes is at least 2.

As an improvement of the utility model, the wastewater collecting mechanism comprises a collecting box and a slag discharge port, and the bottom end of the collecting box is provided with the slag discharge port.

The combined device for the electro-catalytic Fenton oxidation and the narrow-channel double-electrode coupling oxidation and the method for treating the nitrogenous heterocyclic organic matter wastewater by using the combined device are as follows: arranging a plurality of electrode plates in the electrocatalysis area, wherein the electrode plates are made of iron-carbon composite electrodes, the cathode and the anode are respectively connected with a copper bar by a cable, and the copper bar is connected with a voltage-stabilized power supply; the method comprises the following steps that waste water containing nitrogen heterocyclic compounds uniformly enters a reactor body through a water distributor, when the pH value of the nitrogen heterocyclic compounds is adjusted to be 4-5, the waste water flows in an electrocatalytic region of the reactor body and moves upwards along the axial direction of the electrocatalytic region, the hydraulic retention time of the waste water in the region is 2-4h, in the process, under the continuous action of an electric field of a stabilized voltage power supply, an iron-carbon composite anode continuously generates an anodic oxidation reaction, iron loses two electrons to generate nascent ferrous iron and continuously enters the waste water, and the generated ferrous iron is a catalyst of the electrocatalytic-fenton reaction; the wastewater continuously rises along a turnover plate of an electrocatalysis zone until overflowing into the electrocatalysis reaction zone, the hydraulic retention time in the zone is 6-8h, hydrogen peroxide enters the electrocatalysis reaction zone through a medicine adding device, the hydrogen peroxide and nascent state ferrous iron generated by the electrocatalysis zone and flowing into the electrocatalysis reaction zone along with the wastewater react to generate hydroxyl free radicals, then nitrogen-containing heterocyclic compounds are oxidized and degraded in an open loop mode under the action of the hydroxyl free radicals, the wastewater after the electrocatalysis Fenton oxidation treatment continuously rises along the axial direction of the electrocatalysis reaction zone and overflows through an overflow weir to enter a water outlet zone, liquid caustic soda enters the water outlet zone through the medicine adding device, the pH value of the wastewater is adjusted to 8-9, ferric iron converted after Fenton oxidation reacts with the liquid caustic soda to generate ferric hydroxide precipitate, supernatant is discharged from the electrocatalysis Fenton oxidation reactor after staying for 0.5-1 h, and iron mud enters a collection zone, and the water in the water outlet zone enters the tubular reactor and continues to react. The tubular reactor is formed by connecting a plurality of tubular electrodes in series or in parallel, and is formed by nesting a hollow tubular anode and a rod-shaped cathode in parallel from the center of the anode, the side surface of the lower part of the outer wall of the anode is provided with a water inlet, the side surface of the upper part of the outer wall of the anode is provided with a water outlet, wastewater flows in an interlayer between the cathode and the anode, and a water outlet pipe at the tail end of the electro-catalytic Fenton oxidation reactor is divided into a backflow pipe which is connected with a.

The anode substrate of the narrow-channel double-electrode reactor is made of TA1 or TA2 pure titanium, and the surface of the anode substrate can be modified by metal materials such as lead, ruthenium, iridium, tantalum, tin, antimony and the like; the cathode substrate is made of 304/316L stainless steel or pressed graphite powder. The surface can be obtained by modifying polytetrafluoroethylene, carbon black and the like by a sol-gel method.

The principle of the oxidation coupling of the narrow-channel double-electrode reactor and the electro-catalytic Fenton oxidation is as follows: after generating nascent state ferrous iron by electrocatalysis, carrying out Fenton reaction with hydrogen peroxide to generate hydroxyl free radicals, carrying out oxidative decomposition on organic matters, and converting the ferrous iron into ferric iron after the reaction; when ferric iron enters a narrow-channel double-electrode reactor (tubular reactor) along with the wastewater of the nitrogen-containing heterocyclic compound, the nitrogen-containing heterocyclic compound is further degraded by ring opening of hydroxyl radicals generated after the anode surface is electrified by an active layer, the ferric iron is reduced into ferrous iron on the modified cathode surface, and the ferrous iron flows back to the electrocatalytic zone to continuously participate in the electrocatalytic Fenton oxidation reaction. Because the double-electrode reactor is in a narrow channel structure (the distance between a cathode and an anode is 1-2 cm), oxygen generated on the surface of the anode is easily contacted with the surface of the cathode along with water flow to react to generate hydrogen peroxide, and the generated hydrogen peroxide flows back to the electrocatalytic area to continuously participate in Fenton oxidation reaction.

Empirical values by fenton oxidation: the mass concentration of COD in the wastewater to be removed and the mass concentration of hydrogen peroxide are 1:1-1.5, the mass of the required hydrogen peroxide is calculated, the required ferrous concentration is calculated according to the molar ratio of ferrous ions to the hydrogen peroxide of 1:4-10, and the quantity of electrons lost in the electrifying process of the anode required to the required ferrous quantity is calculated according to the coulomb law, so that the required current is obtained. By the electrocatalytic Fenton oxidation process regulated and controlled by the electric field, the dosage of hydrogen peroxide and ferrous ions required by the Fenton reaction can be accurately controlled, so that the economic and efficient degradation effect on the nitrogen-containing heterocyclic compound wastewater is achieved. In addition, the divalent iron ions are efficiently used and reused with the divalent iron ions subjected to coupling oxidation with the narrow-channel double electrodes, so that the generation of iron mud in the Fenton reaction process is greatly reduced, and the subsequent Fenton iron mud treatment cost is reduced.

The utility model discloses a fenton oxidation reaction processing apparatus, with electrocatalytic oxidation technique and the coupling of fenton oxidation technique mutually, the produced new ecological ferrous iron ion of fenton oxidation workshop section can fully utilize the electrocatalytic workshop section as the catalyst, improves the treatment effeciency of fenton oxidation workshop section. Compared with ferrous ions in ferrous sulfate added by traditional Fenton oxidation, the nascent state ferrous iron has higher catalytic activity because the ferrous sulfate is easy to cause powder agglomeration when being diffused in a water body when being added into a Fenton oxidation system, the dissolution speed of the ferrous sulfate is seriously hindered, the contact reaction of the ferrous ions and hydrogen peroxide is greatly reduced, and the Fenton oxidation efficiency is low. The electrocatalysis section can continuously generate nascent state ferrous ions through anodic oxidation, and the nascent state ferrous ions can contact hydrogen peroxide to generate Fenton oxidation reaction after being generated, so that the degradation of nitrogen heterocyclic compound wastewater by the Fenton oxidation reaction is enhanced while the catalytic activity is improved.

Owing to adopted above technique, the utility model discloses compare than prior art, the beneficial effect who has as follows:

(1) the utility model combines the electrocatalytic oxidation and the Fenton oxidation technology, utilizes the effective space of the reactor to the utmost extent, simplifies the process flow of the Fenton oxidation pretreatment, and reduces the operation cost;

(2) the utility model discloses a fenton oxidation reaction processing apparatus, with electrocatalytic oxidation technique and the coupling of fenton oxidation technique mutually, the produced new ecological ferrous iron ion of fenton oxidation workshop section can fully utilize the electrocatalytic workshop section as the catalyst, improves the treatment effeciency of fenton oxidation workshop section. Compared with ferrous iron ions in ferrous sulfate added by traditional Fenton oxidation, the nascent state ferrous iron has higher catalytic activity;

(3) the reaction device has the advantages that the narrow-channel double-electrode reaction section (tubular reactor section) modifies the cathode and the anode simultaneously, so that the oxidation and reduction performances are respectively improved, the surface of the anode can continuously degrade nitrogen-containing heterocyclic compounds remained in Fenton oxidation effluent, the surface of the cathode can reduce ferric iron into ferrous iron to continuously participate in the Fenton reaction, and the multiplexing efficiency of the catalyst is improved; in addition, the design of the narrow channel can enable oxygen generated on the surface of the anode to be more easily contacted with the surface of the cathode to generate hydrogen peroxide, and the oxygen participates in the Fenton oxidation reaction at the front end, so that the consumption of the added hydrogen peroxide is reduced.

Drawings

FIG. 1 is a schematic view showing a structure of a Fenton oxidation treatment apparatus;

FIG. 2 is a schematic view showing an internal structure of a Fenton oxidation treatment apparatus;

FIG. 3 is a schematic structural view of an anode titanium tube;

FIG. 4 is a schematic structural view of a cathode titanium tube;

FIG. 5 is a schematic view of the structure of an electrode reactor;

FIG. 6 is a top view of an electrode reactor;

FIG. 7 is a graph showing the change of COD removal rate at different concentrations of iron ions in example 2;

FIG. 8 is a graph of the trend of the total nitrogen removal for different ferric ion concentrations in example 2;

FIG. 9 is a graph showing the variation of the COD removal rate at different concentrations of hydrogen peroxide in example 3;

FIG. 10 is a graph showing the trend of the total nitrogen removal for different hydrogen peroxide concentrations in example 3;

in the figure: 1. an electro-catalytic Fenton oxidation reactor, 2, a water inlet pipe, 3, a water outlet pipe, 4, a first shell, 5, a water distributor, 6, an electrode plate, 7, a turnover partition plate, 8, an insulating partition plate, 9, a sludge discharge pipe, 10, a second shell, 11, a slag scraping plate, 12, an overflow weir, 13, a tubular reactor, 14, a collecting box, 15, an electrode reactor, 16, an anode titanium flange, 17, an anode titanium pipe, 18, a water inlet, 19, a water outlet, 20, an anode binding post, 21, a cathode titanium flange, 22, a cathode titanium pipe, 23, a cathode binding post, 24, a through hole, 25, a slag discharge port, 26, a third shell, 27 and a return pipe.

Detailed Description

The invention will be further elucidated with reference to the drawings and the detailed description.

Example 1:

a Fenton oxidation reaction treatment device, which comprises an electro-catalytic Fenton oxidation reactor 1, a tubular reactor 13, a water inlet pipe 2 and a water outlet pipe 3, the electro-catalytic Fenton oxidation reactor 1 is connected with a tubular reactor 13, the electro-catalytic Fenton oxidation reactor 1 comprises a wastewater oxidation mechanism and a wastewater collection mechanism, the waste water oxidation mechanism is arranged above the waste water collection mechanism, the lower end of the waste water oxidation mechanism is connected with the waste water collection mechanism through a sludge discharge pipe 9, the wastewater oxidation mechanism comprises an electro-catalysis zone, an electro-catalysis reaction zone and a water outlet zone which are sequentially arranged from left to right, the electrocatalysis zone, the electrocatalysis reaction zone and the water outlet zone are communicated in sequence, the water inlet pipe 2 is connected with the electrocatalysis zone, one end of the tubular reactor 13 is connected with the water outlet area through the water outlet pipe 3, and the other end of the tubular reactor 13 is connected with the water inlet pipe 2 through the return pipe 27.

The electrocatalysis zone comprises a first shell 4, a water distributor 5, a plate electrode 6, a turning partition plate 7 and an insulating partition plate 8, wherein two insulating partition plates 8 are arranged in the first shell 4, the plate electrode 6 is arranged between the two insulating partition plates 8, the two ends of each of the two insulating partition plates 8 are respectively connected with the inner side and the outer side of the first shell 4, the water distributor 5 is arranged above the plate electrode 6, the turning partition plate 7 is arranged above the water distributor 5, and the left side of the first shell 4 is connected with a water inlet pipe 2.

Be equipped with mud pipe 9 on first shell 4, first shell 4 links to each other with waste water collection mechanism through mud pipe 9.

The electrocatalysis reaction zone comprises a second shell 10, a slag scraping plate 11 and an overflow weir 12, wherein the slag scraping plate 11 is arranged at the upper end of the inner side of the second shell 10, and the overflow weir 12 is arranged on both sides of the slag scraping plate 11.

The tubular reactor 13 comprises at least 2 electrode reactors 15, and two adjacent electrode reactors 15 are connected through a pipeline.

The electrode reactor 15 comprises an anode titanium flange 16, an anode titanium pipe 17, a water inlet 18, a water outlet 19, an anode binding post 20, a cathode titanium flange 21, a cathode titanium pipe 22 and a cathode binding post 23; a water inlet 18 is formed in the lower end of one side of the anode titanium pipe 17, a water outlet 19 is formed in the upper end of the other side of the anode titanium pipe 17, an anode binding post 20 is arranged on the right side of the anode titanium pipe 17, and an anode titanium flange 16 is arranged at the upper end of the anode titanium pipe 17; the bottom end of the cathode titanium tube 22 is sealed, the inner side of the anode titanium tube 17 is of a hollow structure, the cathode titanium tube 22 is arranged in the anode titanium tube 17, a gap is arranged between the anode titanium tube 17 and the cathode titanium tube 22, and the anode titanium flange 16 is provided with a through hole 24 corresponding to the cathode titanium tube 22; the upper end of the cathode titanium tube 22 is provided with a cathode titanium flange 21 and a cathode binding post 23, the lower end of the cathode binding post 23 is connected with the cathode titanium tube 22, and the upper end of the cathode binding post 23 is arranged in the cathode titanium flange 21 in a penetrating mode.

The lower end of the second shell 10 is provided with a sludge discharge pipe 9, and the second shell 10 is connected with a wastewater collection mechanism through the sludge discharge pipe 9.

The water outlet mechanism comprises a third shell 26, and the right end of the third shell 26 is connected with the water outlet pipe 3. The lower end of the third shell 26 is provided with a sludge discharge pipe 9, and the third shell 26 is connected with a wastewater collection mechanism through a sludge discharge pipe 3.

The number of the sludge discharge pipes 9 is at least 2.

The wastewater collecting mechanism comprises a collecting box and a slag discharge port 25, and the bottom end of the collecting box is provided with the slag discharge port 25.

The utility model discloses the electro-catalytic Fenton oxidation that adopts and narrow passageway bipolar electrode coupling oxidation composite set are shown as figure 1, reaction unit is including the electro-catalytic Fenton oxidation reactor who is square or cuboid and constitute by the nested narrow passageway bipolar electrode reactor 15 of tubulose. The electro-catalytic Fenton oxidation reactor 1 is divided into an upper part and a lower part, the upper part is divided into three areas of an electro-catalytic area, an electro-catalytic Fenton oxidation area and a water outlet area from left to right, the lower part is a collecting box, the four reaction areas are mutually communicated, and the electro-catalytic area is provided with a plurality of cathode and anode plates which are made of iron-carbon composite materials and are respectively connected with the anode and the cathode of a stabilized voltage power supply. The nitrogen heterocyclic compound wastewater (target pollutant is tetramethyl piperidine amine) treated by the device has obviously reduced organic nitrogen concentration and greatly reduced biotoxicity, enters a subsequent biological aerated filter treatment device and finally achieves standard treatment.

Example 2:

the device is used for treating the tail water discharged in the production of the ultraviolet absorbent UV-P and the light stabilizer, and the COD (chemical oxygen demand) and the total nitrogen removal rate change under different iron ion concentrations are explored.

In the embodiment, ultraviolet light absorber UV-P and tail water discharged in light stabilizer production are taken as research objects, main pollution factors are 2- (2 '' -hydroxy-5 '' -methylphenyl) benzotriazole (molecular formula: C13H11N 3O), tetramethylpiperidine amine and the like, all of which are nitrogen-containing heterocyclic compounds, and the pH value is 6-7; the CODcr of the wastewater is 1245 +/-115 mg/L, the total nitrogen is 182 +/-8.5 mg/L, the ammonia nitrogen is 3.9 +/-1.4 mg/L, the nitrate nitrogen is 17.9 +/-1.6 mg/L, the organic nitrogen (estimated from the total nitrogen-ammonia nitrogen-nitrate nitrogen) is about 160.2 +/-5.5 mg/L, and the main difficult-to-biodegrade components are 2- (2 '' -hydroxy-5 '' -methylphenyl) benzotriazole (molecular formula: C13H11N 3O) and tetramethylpiperidine amine. The tail water discharged in the production of ultraviolet absorbent UV-P and light stabilizer is 2.0m³The flow rate of the water/h enters the electro-catalytic Fenton oxidation reactor 1 from the water inlet 18 and flows in the electro-catalytic zone, at the moment, the doser pumps the sulfuric acid into the electro-catalytic zone, the pH value of the inlet water is adjusted to 4-5, the inlet water moves upwards along the axial direction of the electro-catalytic zone, and the hydraulic retention time is 8 h. In the process, under the continuous action of an electric field of a stabilized voltage supply, the iron-carbon composite anode continuously generates anodic oxidation reaction, iron loses two electrons to generate nascent ferrous iron and continuously enters wastewater, and the generated ferrous iron is a catalyst of electrocatalysis-Fenton reaction; the wastewater continuously rises along the overturning partition plate 7 of the electro-catalysis area until the wastewater overflows into the electro-catalysis Fenton oxidation area, the hydraulic retention time in the area is 6-8h, hydrogen peroxide enters the electro-catalysis Fenton oxidation area through the doser, and the hydrogen peroxide and the electro-catalysis area are generated and flow into a new ecology of the electro-catalysis Fenton oxidation area along with the wastewaterFerrous iron reacts to generate hydroxyl free radical, nitrogen-containing heterocyclic compounds such as 2- (2 '' -hydroxyl-5 '' -methylphenyl) benzotriazole, tetramethylpiperidine amine and the like are oxidized and degraded in an open loop mode under the action of the hydroxyl free radical, scum is scraped into a deslagging area and flows into a deslagging port 25 under the action of a scum scraper 11 (namely an electric scum scraper), wastewater after electrocatalytic Fenton oxidation treatment continuously rises along the axial direction of the electrocatalytic reaction area and overflows through an overflow weir 12 to enter a water outlet area, liquid alkali enters the water outlet area through a medicine adding device, the pH value of the wastewater is adjusted to 8-9, ferric iron converted after Fenton oxidation reacts with the liquid alkali to generate ferric hydroxide precipitate, supernatant liquid is discharged from an electrocatalytic Fenton oxidation reactor after staying for 0.5-1 h, iron sludge enters a collecting box, the wastewater at the water outlet area enters a tubular reactor 13 through a water outlet pipe 3, and subjected to fenton oxidation. The narrow-channel double-electrode reactor 15 is formed by connecting a plurality of tubular electrodes in series or in parallel, and is formed by nesting a hollow tubular anode titanium tube 17 and a rod-shaped cathode titanium tube 22 which are coated with transition metals such as ruthenium, iridium, tantalum, lead and the like on the inner surfaces in parallel from the center of an anode, the side surface of the lower part of the outer wall of the anode is provided with a water inlet 18, the side surface of the upper part of the outer wall of the anode is provided with a water outlet 19, waste water flows in the interlayer between the cathode and the anode, and a return pipe 27 is divided from a water outlet pipe 3. In the process, when ferric iron enters the narrow-channel double-electrode reactor 15 along with tail water discharged in the production of ultraviolet light absorber UV-P and light stabilizer, the hydroxyl free radicals generated after the anode surface of nitrogen-containing heterocyclic compounds such as 2- (2 '' -hydroxy-5 '' -methylphenyl) benzotriazole, tetramethylpiperidylamine and the like are electrified by the active layer are further degraded in an open loop manner, the ferric iron is reduced into ferrous iron on the modified cathode surface, and the ferrous iron flows back to the electrocatalytic zone to continuously participate in the electrocatalytic Fenton oxidation reaction. Because the double-electrode reactor 15 is in a narrow channel structure (the distance between the anode and the cathode is 1-2 cm), oxygen generated on the surface of the anode is easily contacted with the surface of the cathode along with water flow to react to generate hydrogen peroxide, and the generated hydrogen peroxide flows back to the electrocatalytic region to continuously participate in Fenton oxidation reaction.

After the reaction is finished, the pH value is adjusted to 8-9, the reaction product is precipitated for more than 30 minutes, and a sludge discharge pipe 9 is opened to discharge sludge. And when the thickness of the anode of the composite iron-carbon electrode is reduced to be less than 2mm, connecting the positive and negative terminals connected with a power supply in a reverse way, and continuing the coupling oxidation reaction. When the thickness of the cathode and the anode of the composite iron-carbon electrode is reduced to below 2mm, the cathode and the anode are replaced, the replacement frequency of the composite iron-carbon electrode is 2 months, a copper bar and an electrode connecting cable need to be disassembled when the cathode and the anode are replaced, and the composite iron-carbon electrode is replaced after the electrode plate 6 is lifted from bottom to top.

The discharged tail water produced and discharged by the ultraviolet absorbent UV-P and the light stabilizer in the coupling oxidation reaction device can not only obtain good treatment effect, but also reduce the dosage of the medicament and the generation amount of iron mud in the electrocatalytic Fenton oxidation process. When the traditional zero-valent iron reduction-homogeneous Fenton oxidation combined process is adopted for treatment, the yield of iron mud in each ton of wastewater is 12kg, and the adding amount of hydrogen peroxide (the concentration is 27.5 percent) is 4.35L; the oxidation process for reaction by adopting the device described by the utility model reduces the production of iron mud in every ton of wastewater to 2.3kg, and reduces the adding amount of hydrogen peroxide (the concentration is 27.5%) to 1.74L. Therefore, the oxidation process for carrying out the reaction by adopting the device can obviously reduce the medicament cost and the subsequent treatment cost.

Under the reaction conditions of HRT (high temperature treatment) of 20h, hydrogen peroxide addition concentration of 1.74 mL/L and pH value of 5 in an electrocatalytic Fenton oxidation zone, the method determines the removal rate of total nitrogen, the change conditions of nitrate nitrogen and ammonia nitrogen, the removal rate of COD and other indexes in a reaction system, and measures the removal effect of the nitrogen-containing heterocyclic compound in the coupling system.

As can be seen from fig. 7 and 8, after the three target pollutants pass through the electrocatalytic fenton oxidation zone, the main function is to remove the organic nitrogen in the nitrogen-containing heterocyclic compound, and the organic nitrogen is converted into ammonia nitrogen to be released through ring opening, so that the two target pollutants are substantially completely removed after passing through the zone, and the removal rate is higher than 80%. The flocculation or sweeping action of the settling zone further removes pollutants in the wastewater, so that small molecular organic matters after degradation of nitrogen-containing heterocyclic pollutants such as 2- (2 '' -hydroxy-5 '' -methylphenyl) benzotriazole, tetramethylpiperidine amine and the like can be further removed. The great reduction of the iron mud and the great reduction of the dosage of the hydrogen peroxide also indicate that the narrow-channel cathode has a strong reduction effect on the ferric iron, and can convert the ferric iron into the ferrous iron with high efficiency to continuously act on an electro-catalytic Fenton oxidation zone to continuously react with the hydrogen peroxide.

Example 3:

the HRT is set to be 20h, the pH value of the electro-Fenton oxidation area is 6, the pumping amount of hydrogen peroxide in the chemical feeder is adjusted, and the influence of different hydrogen peroxide feeding concentrations on the change of COD (chemical oxygen demand) and total nitrogen removal rate is explored.

As can be seen from fig. 9, the total nitrogen of the wastewater after 20 hours of treatment is gradually reduced, and especially when the adding concentration of hydrogen peroxide is 0.6 per mill, the reduction of the total nitrogen is most obvious, which indicates that the removal effect of the target organic nitrogen-containing pollutant is best under the condition of the adding concentration of hydrogen peroxide. The result shows that when the adding concentration of the hydrogen peroxide is lower, the electrocatalytic Fenton effect is not obvious; when the concentration of the hydrogen peroxide is higher, the electrocatalytic Fenton oxidation effect is also inhibited.

As can be seen from fig. 10, the removal rate of COD in the effluent water is gradually increased after 20 hours, and when the addition concentration of hydrogen peroxide is 0.6 per mill and the ferrous ion concentration in the system is controlled at 400 mg/L, the constructed fenton system has a good treatment effect, and the removal rate of COD is the highest. The total nitrogen removal effect of the wastewater is best under the condition of the hydrogen peroxide concentration.

The above-mentioned embodiments are merely preferred technical solutions of the present invention, and should not be regarded as limitations of the present invention, and the protection scope of the present invention should be protected by the technical solutions described in the claims, and equivalent alternatives including technical features in the technical solutions described in the claims are also within the protection scope of the present invention.

Claims

1. A Fenton oxidation reaction processing apparatus characterized in that: including electro-catalytic Fenton oxidation reactor, tubular reactor, inlet tube and outlet pipe, electro-catalytic Fenton oxidation reactor links to each other with tubular reactor, electro-catalytic Fenton oxidation reactor includes waste water oxidation mechanism and waste water collection mechanism, waste water oxidation mechanism sets up the top of collecting the mechanism at waste water, waste water oxidation mechanism lower extreme is through mud pipe and waste water collection mechanism link to each other, waste water oxidation mechanism includes electro-catalysis district, reaction zone and the pool that from left to right sets gradually, be linked together in proper order between electro-catalysis district, reaction zone and the pool, the inlet tube links to each other with the electro-catalysis district, tubular reactor one end is passed through the outlet pipe and is linked to each other with the pool, the tubular reactor other end passes through the back flow and links to each other with the inlet tube.

2. A fenton oxidation reaction treatment apparatus according to claim 1, characterized in that: the electrocatalysis zone comprises a first shell, a water distributor, a plate electrode, a turning partition plate and an insulating partition plate, wherein two insulating partition plates are arranged in the first shell, the plate electrode is arranged between the two insulating partition plates, two ends of each insulating partition plate are respectively connected with the inner side and the outer side of the first shell, the water distributor is arranged above the plate electrode, the turning partition plate is arranged above the water distributor, and the left side of the first shell is connected with a water inlet pipe.

3. A fenton oxidation reaction treatment apparatus according to claim 2, characterized in that: be equipped with the mud pipe on the first shell, first shell passes through the mud pipe and links to each other with waste water collection mechanism.

4. A fenton oxidation reaction treatment apparatus according to claim 1, characterized in that: the reaction zone comprises a second shell, a slag scraping plate and an overflow weir, wherein the slag scraping plate is arranged at the upper end of the inner side of the second shell, and the overflow weir is arranged on each of two sides of the slag scraping plate.

5. A fenton oxidation reaction treatment apparatus according to claim 1, characterized in that: the tubular reactor comprises at least 2 electrode reactors, and two adjacent electrode reactors are connected through a pipeline.

6. A Fenton's oxidation reaction processing apparatus according to claim 5, characterized in that: the electrode reactor comprises an anode titanium flange, an anode titanium pipe, a water inlet, a water outlet, an anode binding post, a cathode titanium flange, a cathode titanium pipe and a cathode binding post; the lower end of one side of the anode titanium pipe is provided with a water inlet, the upper end of the other side of the anode titanium pipe is provided with a water outlet, the right side of the anode titanium pipe is provided with an anode wiring terminal, and the upper end of the anode titanium pipe is provided with an anode titanium flange; the bottom end of the cathode titanium pipe is sealed, the inner side of the anode titanium pipe is of a hollow structure, the cathode titanium pipe is arranged in the anode titanium pipe, a gap is arranged between the anode titanium pipe and the cathode titanium pipe, and a through hole corresponding to the cathode titanium pipe is arranged on the anode titanium flange; the cathode titanium tube upper end is equipped with cathode titanium flange and cathode terminal, and cathode terminal lower extreme links to each other with the cathode titanium tube, the cathode terminal upper end runs through the setting in cathode titanium flange.

7. A Fenton's oxidation reaction processing apparatus according to claim 4, characterized in that: and a sludge discharge pipe is arranged at the lower end of the second shell, and the second shell is connected with the wastewater collecting mechanism through the sludge discharge pipe.

8. A fenton oxidation reaction treatment apparatus according to claim 1, characterized in that: the water outlet area comprises a third shell, and the right end of the third shell is connected with a water outlet pipe; and a sludge discharge pipe is arranged at the lower end of the third shell, and the third shell is connected with the wastewater collecting mechanism through the sludge discharge pipe.

9. A fenton oxidation reaction treatment apparatus according to claim 3, 7 or 8, characterized in that: the number of the sludge discharge pipes is at least 2.

10. A fenton oxidation reaction treatment apparatus according to claim 1, characterized in that: the waste water collecting mechanism comprises a collecting box and a slag discharge port, and the bottom end of the collecting box is provided with the slag discharge port.