Organic wastewater advanced treatment system based on Fenton oxidation reaction

Abstract

The utility model provides an organic wastewater advanced treatment system based on Fenton oxidation reaction, and relates to the field of wastewater treatment. The organic wastewater advanced treatment system based on the Fenton oxidation reaction comprises a Fenton oxidation module, an advanced oxidation module, a neutralization and flocculation module and a precipitation module which are connected in sequence, the Fenton oxidation module is communicated with the deep oxidation module through a pipeline, the Fenton oxidation module is provided with a water inlet pipe, a first adding point and a second adding point, the first adding point is used for adding ferrous sulfate, the second adding point is used for adding hydrogen peroxide, the deep oxidation module is provided with a third adding point, and the third adding point is used for adding chlorine dioxide; the deep oxidation module, the neutralization and flocculation module and the precipitation module are co-constructed, and the common wall slots of every two adjacent modules are communicated. The system can effectively remove non-biodegradable substances in wastewater in industries such as printing and dyeing, pulping and papermaking and the like, and reduces the generation of chemical sludge at the same time.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wastewater treatment, in particular, relates to a kind of organic wastewater advanced treatment system based on Fenton oxidation reaction. BACKGROUND

[0002] There are many pollutants in organic wastewater that cannot be biodegraded, such as pigment substances in printing and dyeing industry wastewater, lignin substances in pulp and paper industry wastewater, etc. With the improvement of wastewater discharge standards, the existing sewage treatment facilities cannot meet the wastewater discharge standards when treating wastewater that is difficult to biodegrade.

[0003] Fenton oxidation process generates strong oxidizing substances such as hydroxyl radicals and peroxide radicals by generating hydroxyl radicals and hydrogen peroxide under acidic conditions, which oxidize and mineralize dissolved organic matter. In addition, chlorine dioxide removes organic chromophores and auxiliary chromophores in wastewater through oxidation and decolorization process to achieve the purpose of decolorization. The mainstream reaction of Fenton process is to adjust the pH value of wastewater to 3-5 by concentrated sulfuric acid, then enter the Fenton oxidation tank or oxidation tower, add ferrous sulfate and hydrogen peroxide in the oxidation tank or oxidation tower, and send the effluent of the oxidation tank or oxidation tower to the neutralization and degassing tank. According to the actual pH value of the neutralization and degassing tank, liquid alkali is added to adjust the pH value to neutral, and polyacrylamide flocculant is added at a single point in the neutralization and degassing tank to flocculate with the iron sludge generated during the reaction. After flocculation, the sewage enters the final sedimentation tank, and the iron sludge settles to the bottom of the tank under the action of its own gravity, realizing the separation of sludge and water. The supernatant of the final sedimentation tank meets the discharge standard, and the sludge of the final sedimentation tank is sent to the sludge dewatering treatment system for treatment. In the traditional Fenton reaction, the Fenton reagent has strong oxidizing ability because it contains Fe 2+ and H2O2, H2O2 is catalytically decomposed by ferrous ions to generate hydroxyl radicals (·OH), and the essence of Fenton reagent treatment of organic pollutants is the reaction of hydroxyl radicals with organic matter. The traditional Fenton reaction uses Fenton reagent to treat wastewater, which requires a large amount of chemicals and generates a large amount of chemical sludge, resulting in high treatment cost. UTILITY MODEL CONTENT

[0004] The purpose of the embodiment of the present application is to provide an organic wastewater advanced treatment system based on Fenton oxidation reaction, to alleviate the technical problems of high cost of treating wastewater and generation of a large amount of chemical sludge in the prior art.

[0005] In order to solve the above technical problems, the technical scheme provided by the present application is:

[0006] The organic wastewater advanced treatment system based on Fenton oxidation reaction provided by the present application comprises a Fenton oxidation module, a deep oxidation module, a neutralization and flocculation module and a sedimentation module connected in sequence;

[0007] The Fenton oxidation module and the advanced oxidation module are communicated by a pipeline, and the Fenton oxidation module has a water inlet pipe, a first dosing point for adding ferrous sulfate and a second dosing point for adding hydrogen peroxide, and the advanced oxidation module has a third dosing point for adding chlorine dioxide;

[0008] The advanced oxidation module, the neutralization and flocculation module and the precipitation module are built together, and the common walls of two adjacent modules are slotted and communicated.

[0009] Further, the Fenton oxidation module comprises an oxidation bed, a cyclone water distributor and a solid-liquid separator, the top of the oxidation bed is provided with a water distribution tank, a first dosing tank and a second dosing tank, the water distribution tank is located between the first dosing tank and the second dosing tank and is communicated with the first dosing tank and the second dosing tank; the water distribution tank is provided with the water inlet pipe, the first dosing tank is provided with the first dosing point, and the second dosing tank is provided with the second dosing point.

[0010] The cyclone water distributor and the solid-liquid separator are located in the oxidation bed, the cyclone water distributor is located below the solid-liquid separator, and the first dosing tank and the second dosing tank are respectively communicated with the cyclone water distributor through two circulating stirring pipes.

[0011] Further, the oxidation bed is provided with quartz sand fillers, the quartz sand filler carrier increases the reaction contact specific surface area, and the carrier is attached with a heterogeneous catalyst, which can reduce the consumption of ferrous sulfate and thus reduce the amount of chemical sludge.

[0012] Further, the cyclone water distributor comprises a water distribution cover and a water distribution pipe, and the water distribution pipe is in fluid communication with the circulating stirring pipe.

[0013] The water distribution cover is in the shape of a cone with the cone angle upward, is located above the water distribution pipe, is provided with a through hole and plays a role of cyclone, thereby avoiding short flow.

[0014] Further, the advanced oxidation module comprises an advanced oxidation tank, a first water outlet weir at the top of the oxidation bed is communicated with the advanced oxidation tank through a water outlet pipe, and the advanced oxidation tank is provided with the third dosing point.

[0015] The advanced oxidation tank and the neutralization and flocculation module are communicated through a first communication hole at the lower part of the common wall.

[0016] Further, the advanced oxidation tank is provided with a first perforated aeration pipe at the bottom.

[0017] Further, the neutralization and flocculation module comprises a neutralization tank and a flocculation tank, the neutralization tank is communicated with the advanced oxidation tank; the neutralization tank is communicated with the flocculation tank through the second communication hole in the upper part of the common wall;

[0018] The flocculation tank is communicated with the sedimentation module through the third communication hole in the lower part of the common wall.

[0019] Further, the bottom of the neutralization tank is provided with a second perforated aeration pipe.

[0020] Further, the bottom of the flocculation tank is provided with a third perforated aeration pipe; or, the flocculation tank is provided with a stirrer.

[0021] Further, the sedimentation module comprises a buffer tank and a sedimentation tank, the buffer tank is communicated with the neutralization and flocculation module; the buffer tank is communicated with the sedimentation tank through the fourth communication hole in the middle part of the common wall, and the sedimentation tank is provided with a sludge collecting tank and an inclined plate, the sludge collecting tank is located at the bottom of the sedimentation tank, and the inclined plate is located between the fourth communication hole and the second water outlet weir of the sedimentation tank along the height direction of the sedimentation tank.

[0022] Based on the above technical solutions, the technical effects realized by the utility model are analyzed as follows:

[0023] The organic wastewater advanced treatment system based on Fenton oxidation reaction provided by the utility model comprises a Fenton oxidation module, an advanced oxidation module, a neutralization and flocculation module and a sedimentation module which are connected in sequence; the Fenton oxidation module is communicated with the advanced oxidation module through a pipeline, and the Fenton oxidation module has a water inlet pipe, a first dosing point and a second dosing point, the first dosing point is used for adding ferrous sulfate, the second dosing point is used for adding hydrogen peroxide, the advanced oxidation module has a third dosing point, and the third dosing point is used for adding chlorine dioxide; the advanced oxidation module, the neutralization and flocculation module and the sedimentation module are jointly built, and the common wall of two adjacent modules is grooved and communicated. The system is usually arranged after an aerobic biological treatment system, of course, the system is within the protection scope of the utility model whether it is used in cooperation with other systems or alone.

[0024] The system comprises a Fenton oxidation module, an advanced oxidation module, a neutralization and flocculation module and a sedimentation module which are connected in sequence, and ferrous sulfate can be added into the Fenton oxidation module through the first dosing point, hydrogen peroxide can be added into the Fenton oxidation module through the second dosing point, and chlorine dioxide can be added into the advanced oxidation module through the third dosing point, so that the Fenton oxidant, chlorine dioxide and coagulation and sedimentation technology are combined for use, a large amount of organic matter and toxic chemical substances in sewage can be effectively removed, the use amount of Fenton reagent ferrous sulfate and hydrogen peroxide can be significantly reduced, and the generation of iron sludge is reduced. Compared with the traditional Fenton oxidation process, the system can save the medicine cost of wastewater treatment and reduce the generation of solid waste iron sludge.

[0025] The principle of the system is that the Fenton reagent-ferric sulfate and hydrogen peroxide to be added is less than the traditional Fenton system, and the chlorine dioxide is reused due to its strong oxidizing property and easy solubility in water. The CIO2 molecule has 19 valence electrons and one unpaired electron, and exists in the form of a very rare monomer free radical, so CIO2 has very strong oxidizing ability, which is more than 2.5 times that of HOCl. The combination of Fenton oxidation, chlorine dioxide oxidation and coagulation and sedimentation technology can greatly improve the reaction effect, shorten the reaction time and reduce the operation cost.

[0026] The organic wastewater advanced treatment system based on Fenton oxidation reaction can effectively remove the refractory organic matter in the organic wastewater and reduce the suspended particulate matter in the wastewater, so as to achieve the effect of wastewater advanced treatment. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly introduced as follows. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0028] Figure 1 The structural schematic diagram of the organic wastewater advanced treatment system based on Fenton oxidation reaction provided by the embodiments of the present application is shown in the figure.

[0029] Figure 2 The structural schematic diagram of the Fenton oxidation module in the organic wastewater advanced treatment system based on Fenton oxidation reaction provided by the embodiments of the present application is shown in the figure.

[0030] Figure 3 The structural schematic diagram of the advanced oxidation module in the organic wastewater advanced treatment system based on Fenton oxidation reaction provided by the embodiments of the present application is shown in the figure.

[0031] Figure 4 The schematic diagram of each dosing point in the organic wastewater advanced treatment system based on Fenton oxidation reaction provided by the embodiments of the present application is shown in the figure.

[0032] Icon:

[0033] 100-Fenton oxidation module; 110-oxidation bed; 120-cyclone water distributor; 121-water distribution cover; 122-water distribution pipe; 130-solid-liquid separator; 140-water distribution tank; 141-inlet pipe; 150-first dosing tank; 151-first dosing point; 160-second dosing tank; 161-second dosing point; 170-circulating stirring pipe; 171-circulating stirring pump; 180-first water outlet weir; 190-outlet pipe;

[0034] 200 - depth oxidation module; 210 - depth oxidation tank; 211 - third dosing point; 212 - first communication hole; 213 - first perforated aeration pipe; 220 - aeration blower;

[0035] 300 - neutralization and flocculation module; 310 - neutralization tank; 313 - second perforated aeration pipe; 312 - second communication hole; 311 - fourth dosing point; 320 - flocculation tank; 322 - third communication hole; 323 - agitator; 321 - fifth dosing point;

[0036] 400 - sedimentation module; 410 - buffer tank; 411 - fourth communication hole; 420 - sedimentation tank; 421 - sludge collector; 422 - inclined plate; 423 - second outlet weir. DETAILED DESCRIPTION

[0037] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0038] In the description of the present application, it should be noted that the positions or location relations indicated by the terms "inner", "outer" and the like are based on the positions or location relations shown in the drawings, or the positions or location relations in which the products of the present application are usually placed, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular position, be constructed and operated in a particular position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" and the like are only used to distinguish description, and cannot be understood as indicating or implying relative importance.

[0039] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "set", "connected" should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be directly connected, or indirectly connected through an intermediate medium; can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0040] Reference is made to Figures 1 to 4The embodiment of the utility model provides a based on fenton oxidation reaction's organic wastewater advanced treatment system including the Fenton oxidation module 100, the depth oxidation module 200, the neutralization flocculation module 300 and the sedimentation module 400 that connect gradually, and the Fenton oxidation module 100 is communicated with the depth oxidation module 200 through the pipeline, and the Fenton oxidation module 100 has inlet pipe 141, first dosing point 151 and second dosing point 161, and first dosing point 151 is used for adding ferrous sulfate, and second dosing point 161 is used for adding hydrogen peroxide, and the depth oxidation module 200 has third dosing point 211, and third dosing point 211 is used for adding chlorine dioxide, the depth oxidation module 200, the neutralization flocculation module 300 and the sedimentation module 400 are built together, and the common wall of adjacent two modules is grooved and communicated. The system is usually set behind the aerobic biological treatment system, of course, the system and other systems cooperate or are used alone are within the protection scope of the utility model.

[0041] Specifically, the top of the Fenton oxidation bed 110 is connected with the depth oxidation module 200 through a pipeline. The system needs to meet the condition that the inlet water is acidic. To meet the activity of subsequent Fenton oxidation and chloro-oxidation reaction, the pH value of the wastewater needs to be adjusted to 3-5 by concentrated sulfuric acid before entering the Fenton oxidation module 100, and enters the Fenton oxidation module 100 from the inlet pipe 141. The system improves the effective utilization rate of hydroxyl radicals and chlorine dioxide monomer radicals, reduces the dosing amount of ferrous sulfate and hydrogen peroxide; by using the strong solubility in water and strong oxidizing property of chlorine dioxide, the double-oxidation holding is carried out, the chemical oxidation mud production is reduced; the organic matter index in the wastewater is reduced as a whole, the drug dosing amount and mud production are reduced, the system operation cost is reduced, and the system operation stability and impact resistance are improved.

[0042] The system includes the Fenton oxidation module 100, the depth oxidation module 200, the neutralization flocculation module 300 and the sedimentation module 400 connected in sequence, and ferrous sulfate can be added into the Fenton oxidation module 100 through the first dosing point 151, hydrogen peroxide can be added into the Fenton oxidation module 100 through the second dosing point 161, and chlorine dioxide can be added into the depth oxidation module 200 through the third dosing point 211, so that the Fenton oxidant, chlorine dioxide and coagulation and sedimentation technology are combined for use, a large amount of organic matter and toxic chemical substances in sewage can be effectively removed, the use amount of ferrous sulfate and hydrogen peroxide as Fenton reagent can be significantly reduced, and the generation of iron mud is reduced. Compared with the traditional Fenton oxidation process, the system can save the drug cost of wastewater treatment, and reduce the generation of solid waste iron mud.

[0043] The principle of the system is that the Fenton reagent-ferric sulfate and hydrogen peroxide to be added is less than that of the traditional Fenton system, and the chlorine dioxide is reused due to its easy solubility in water and strong oxidizing property. The CIO2 molecule has 19 valence electrons and one unpaired electron, and exists in the form of a very rare monomer free radical, so the CIO2 has strong oxidizing capacity, which is more than 2.5 times of that of HOCl. After the Fenton reagent reaction, the pH of the wastewater is between 5 and 6, at this time, the CIO2 aqueous solution has the best effect under the condition of pH 6. The combination of the Fenton oxidation, chlorine dioxide oxidation and coagulation sedimentation technology can greatly improve the reaction effect, shorten the reaction time and reduce the operation cost. The organic wastewater deep treatment system based on the Fenton oxidation reaction can effectively remove the difficult biodegradable organic matter in the organic wastewater and reduce the suspended particulate matter in the wastewater, so as to achieve the effect of wastewater deep treatment.

[0044] The structure of the Fenton oxidation module 100 is described in detail as follows:

[0045] In the optional scheme of the embodiment of the utility model, referring to Figure 1 、 Figure 2 and Figure 4 , the Fenton oxidation module 100 comprises an oxidation bed 110, a cyclone water distributor 120 and a solid-liquid separator 130, the top of the oxidation bed 110 is provided with a water distribution tank 140, a first dosing tank 150 and a second dosing tank 160, the water distribution tank 140 is located between the first dosing tank 150 and the second dosing tank 160 and is in communication with the first dosing tank 150 and the second dosing tank 160; the water distribution tank 140 is provided with a water inlet pipe 141, the first dosing tank 150 is provided with a first dosing point 151, and the second dosing tank 160 is provided with a second dosing point 161; the cyclone water distributor 120 and the solid-liquid separator 130 are both located in the oxidation bed 110, the cyclone water distributor 120 is located below the solid-liquid separator 130, and the first dosing tank 150 and the second dosing tank 160 are respectively in communication with the cyclone water distributor 120 through two circulating stirring pipes 170.

[0046] Specifically, the water distribution tank 140 is communicated with the first dosing tank 150 and the second dosing tank 160 through perforated plates. Water is fed into the water distribution tank 140, ferrous sulfate solution is added into the first dosing tank 150, and hydrogen peroxide is added into the second dosing tank 160. The outlet of the first dosing tank 150 and the outlet of the second dosing tank 160 are both connected with a circulating stirring pipe 170, which is provided with a circulating stirring pump 171. The other end of the circulating stirring pipe 170 extends into the oxidation bed 110 and is connected with the cyclone water distributor 120 located at the bottom of the oxidation bed 110. Preferably, the horizontal cross section of the oxidation bed 110 is circular, the water distribution tank 140 is located in the middle of the first dosing tank 150 and the second dosing tank 160, and the water distribution tank 140, the first dosing tank 150 and the second dosing tank 160 divide the half horizontal cross section of the oxidation bed 110 into three equal parts. The solid-liquid separator 130 and the cyclone water distributor 120 are arranged at intervals along the height direction of the oxidation bed 110, and a Fenton reaction zone is formed between the two. A first water outlet weir 180 is arranged at the bottom of the oxidation tank.

[0047] The effluent from the pH-adjusted secondary sedimentation tank is pumped into the water inlet pipe 141 of the oxidation bed 110, which is connected with the top of the water distribution tank 140. The lower part of the water distribution tank 140 is communicated with the lower part of the first dosing tank 150 and the second dosing tank 160 through perforated plates. The upper part of the first dosing tank 150 and the second dosing tank 160 is communicated with the bottom of the oxidation bed 110 through the circulating stirring pipe 170, which is provided with the circulating stirring pump 171. The cyclone water distributor 120 is arranged at the bottom of the oxidation bed 110. The Fenton reaction zone is formed above the cyclone water distributor 120. The solid-liquid separator 130 is arranged at the upper part of the oxidation bed 110. The suspended solids which are not fully oxidized and coagulated with iron ions are separated by the solid-liquid separator 130. The first water outlet weir 180 is arranged at one side of the top of the oxidation bed 110, and is connected with the advanced oxidation module 200 through the water outlet pipe 190. A large amount of organic matter and toxic chemicals in the wastewater are effectively oxidized in this stage, thereby reducing the load of subsequent treatment.

[0048] As another embodiment, the Fenton oxidation module 100 comprises an oxidation bed 110, a cyclone water distributor 120 and a solid-liquid separator 130. The water distribution tank 140 and the dosing tank are arranged at the top of the oxidation bed 110. The water distribution tank 140 is provided with a water inlet pipe 141 and a first dosing point 151, and the dosing tank is provided with a second dosing point 161. The cyclone water distributor 120 and the solid-liquid separator 130 are both arranged in the oxidation bed 110. The cyclone water distributor 120 is located below the solid-liquid separator 130. The dosing tank is communicated with the cyclone water distributor 120 through a circulating pipe.

[0049] In an optional solution of the embodiment of the utility model, the oxidation bed 110 is internally provided with quartz sand filler.

[0050] The quartz sand filler in the oxidation bed 110 increases the reaction contact specific surface area of the carrier and serves as a carrier for heterogeneous reaction, that is, the quartz sand filler is attached with a heterogeneous catalyst, so that the consumption of ferrous sulfate can be reduced, thereby reducing the amount of chemical sludge.

[0051] In an optional solution of the embodiment of the utility model, the cyclone water distributor 120 comprises a water distribution cover 121 and a water distribution pipe 122, the water distribution pipe 122 is in fluid communication with the circulating stirring pipe 170; the water distribution cover 121 is conical with a taper angle upward, is located above the water distribution pipe 122, and is provided with a through hole, thereby playing a role of cyclone, and further avoiding short flow.

[0052] Specifically, the cyclone water distributor 120 comprises two parts, the water distribution pipe 122 of four sides or six sides for first mixing; the water distribution cover 121 of umbrella shape is arranged on the water distribution pipe 122, a linear opening hole of 45° angle is arranged at the oblique edge position of the water distribution cover 121, so that the water flow forms a cyclone flow state, the mixing of the secondary medicament and the wastewater is formed, short flow is avoided, and the problem of direct water outlet is further avoided.

[0053] The water distribution pipe 122 and the water distribution cover 121 are matched, and the problem of short flow is avoided.

[0054] The structure of the depth oxidation module 200 is described in detail as follows:

[0055] Referring to Figure 1 、 Figure 3 and Figure 4 In an optional solution of the embodiment of the utility model, the depth oxidation module 200 comprises a depth oxidation tank 210, the first water outlet weir 180 at the top of the oxidation bed 110 is in communication with the depth oxidation tank 210 through the water outlet pipe 190, and the depth oxidation tank 210 is provided with a third dosing point 211; the depth oxidation tank 210 is in communication with the neutralization and flocculation module 300 through the first communication hole 212 at the lower part of the common wall.

[0056] Specifically, the depth oxidation tank 210 is dosed with chlorine dioxide solution; the third dosing point 211 is located at the top of the depth oxidation tank 210. Further, the first water outlet weir 180 at the top of the oxidation bed 110 is in communication with the top of the depth oxidation tank 210 through the water outlet pipe 190.

[0057] The top of the depth oxidation tank 210 is in communication with the oxidation bed 110, and the bottom is in communication with the neutralization and flocculation module 300, so that the flow path of the liquid in the depth oxidation tank 210 is increased, and sufficient oxidation is achieved.

[0058] In an optional solution of the embodiment of the utility model, the bottom of the depth oxidation tank 210 is provided with a first perforated aeration pipe 213.

[0059] Specifically, the air released from the first perforated aeration pipe 213 comes from the matched aeration blower 220; further, the first perforated aeration pipe 213 is arranged as an equidistant perforated aeration pipe, the equidistant perforated aeration pipe is staggered downward at an angle of 45 degrees, the perforated shape is circular, the hole diameter is set to 5mm, and the hole distance is set to 10cm or 20mm. Of course, the perforated shape, the hole diameter and the hole distance are set to other shapes and values, which should be within the protection scope of the embodiments of the utility model.

[0060] The compressed air released from the first perforated aeration pipe 213 comes from the matched aeration blower 220, and the stirring of the compressed air can make the chlorine dioxide fully react with the residual organic matter in the water.

[0061] The structure of the neutralization and flocculation module 300 is described in detail as follows:

[0062] Referring to Figure 1 and Figure 4 In the optional scheme of the embodiments of the utility model, the neutralization and flocculation module 300 comprises a neutralization tank 310 and a flocculation tank 320, the neutralization tank 310 is communicated with the advanced oxidation tank 210; the neutralization tank 310 and the flocculation tank 320 are communicated through the second communication hole 312 on the upper part of the common wall; the flocculation tank 320 and the sedimentation module 400 are communicated through the third communication hole 322 on the lower part of the common wall.

[0063] Specifically, the top of the neutralization tank 310 is provided with a fourth dosing point 311, the fourth dosing point 311 is used for adding NaOH, the liquid alkali dosing device and the pH detector placed in the neutralization tank 310 are interlocked through an automatic control system, the set value of the pH is 6.0-6.2, and the liquid alkali dosing device is started and stopped according to the actual pH value fed back by the pH detector, so as to control the pH value in the neutralization tank 310. The top of the flocculation tank 320 is provided with a fifth dosing point 321, the fifth dosing point 321 is used for adding polyacrylamide, and the polyacrylamide dosing flow is interlocked with the flow meter for monitoring the flow of the water inlet pipe 141 of the oxidation bed 110; the polyacrylamide dosing flow is adjusted according to the actual flow value fed back by the flow meter.

[0064] The neutralization tank 310 and the flocculation tank 320 are communicated through the second communication hole 312 on the upper part, the wastewater enters the flocculation tank 320 through the second communication hole 312 on the upper part of the neutralization tank 310, the path of the liquid flow is increased, and the liquid is fully neutralized and flocculated.

[0065] In the optional scheme of the embodiments of the utility model, the bottom of the neutralization tank 310 is provided with a second perforated aeration pipe 313.

[0066] Specifically, in the embodiment, the second perforated aeration pipe 313 shares an aeration fan 220 with the first perforated aeration pipe 213, thereby saving cost; and the second perforated aeration pipe 313 is identical in size and shape with the first perforated aeration pipe 213.

[0067] The bottom of the neutralization tank 310 is provided with the second perforated aeration pipe 313, and compressed air released from the second perforated aeration pipe 313 comes from a matched aeration fan 220; the air released from the second perforated aeration pipe 313 can be used to stir the water to release carbon dioxide, and the compressed air can be used to blow off residual hydrogen peroxide and reaction product carbon dioxide, thereby eliminating the influence of hydrogen peroxide on COD detection.

[0068] In an optional scheme of the embodiment, the bottom of the flocculation tank 320 is provided with a third perforated aeration pipe; or, the flocculation tank 320 is provided with a stirrer 323.

[0069] Specifically, the flocculation tank 320 is provided with the stirrer 323, and the wastewater is subjected to flocculation reaction in the flocculation tank 320, and suspended organic matter and colloidal matter in the wastewater are coagulated together through the rolling and sweeping action. The flocculated wastewater enters the sedimentation module 400. Alternatively, the bottom of the flocculation tank 320 is provided with the third perforated aeration pipe.

[0070] The flocculation tank 320 is provided with the third perforated aeration pipe or the stirrer 323, thereby improving the flocculation effect.

[0071] The structure of the sedimentation module 400 is described in detail as follows:

[0072] Referring to Figure 1 In an optional scheme of the embodiment, the sedimentation module 400 includes a buffer tank 410 and a sedimentation tank 420, the buffer tank 410 is in communication with the neutralization and flocculation module 300; the buffer tank 410 and the sedimentation tank 420 are in communication through a fourth communication hole 411 in the middle of a common wall, and the sedimentation tank 420 is provided with a sludge collecting hopper 421 and an inclined plate 422, the sludge collecting hopper 421 is located at the bottom of the sedimentation tank 420, and the inclined plate 422 is located between the fourth communication hole 411 and a second water outlet weir 423 of the sedimentation tank 420 along the height direction of the sedimentation tank 420.

[0073] Specifically, the flocculated wastewater is buffered in the buffer tank 410 and then enters the sedimentation tank 420, and the wastewater mixture is fully precipitated in the sedimentation tank 420. The solid-phase sludge is precipitated to the sludge collecting hopper 421 at the bottom, and is discharged through the sludge pipe arranged at the bottom of the sludge collecting hopper 421. The liquid-phase supernatant is clarified again through the inclined plate 422, flows through the second water outlet weir 423 arranged at one side of the top of the sedimentation tank 420, and the wastewater meeting the standard is finally discharged through the second water outlet weir 423. The inclined plate 422 is used to prevent floating objects from being carried away by the water flow. The sedimentation zone is between the sludge collecting hopper 421 and the inclined plate 422, and the clarification zone is above the inclined plate 422. Of course, the sedimentation module 400 is arranged in a radial flow sedimentation process, which should also be within the protection scope of the embodiments of the present application.

[0074] The buffer tank 410 is used to guide the water inlet of the sedimentation tank 420; the wastewater is subjected to solid-liquid separation in the sedimentation tank 420, and the supernatant is discharged. The supernatant in the sedimentation tank 420 is discharged after meeting the standard, and the sludge is pumped to the sludge dewatering treatment system matched with the sewage plant for treatment.

[0075] The process of the organic wastewater advanced treatment system based on the Fenton oxidation reaction is exemplified as follows:

[0076] The wastewater enters the oxidation bed 110 through the water inlet pipe 141, and ferrous sulfate and hydrogen peroxide are added to the oxidation bed 110 through the dosing pump. The first dosing point 151 is arranged above the first dosing tank 150, the second dosing point 161 is arranged above the second dosing tank 160, and the dosing flow rate is interlocked with the flow rate of the water inlet pipe 141. The wastewater after adding the Fenton reaction reagent is delivered to the bottom of the Fenton oxidation bed 110 through the circulating stirring pump 171, the wastewater rotates and rises upward from the bottom of the oxidation bed 110, and the wastewater after the Fenton oxidation reaction enters the advanced oxidation tank 210, the neutralization tank 310 and the flocculation tank 320 in sequence. The sewage first enters the advanced oxidation tank 210, the third dosing point 211 for adding ClO2 is arranged above the advanced oxidation tank 210, and CIO2 reacts with the residual organic matter in the water under the action of air stirring. The sewage then enters the neutralization tank 310, the fourth dosing point 311 for adding NaOH is arranged above the neutralization tank 310, the liquid alkali dosing device can be interlocked with the pH detector, the pH is set to 6.0-6.2, and the liquid alkali dosing device is started and stopped according to the pH feedback value logic. The sewage then enters the flocculation tank 320, the fifth dosing point 321 for adding polyacrylamide is arranged above the water inlet of the flocculation tank 320, and the polyacrylamide dosing flow rate is interlocked with the flow rate monitored by the water inlet pipe 141. The supernatant is discharged through the second water outlet weir 423 of the sedimentation tank 420 after the wastewater is fully subjected to solid-liquid separation in the sedimentation tank 420.

[0077] It should be noted that the features in the embodiments in the present application can be combined with each other without conflict.

[0078] The above descriptions are only the preferred embodiments of the present application, and are not intended to limit the present application. The present application can have various modifications and changes for those skilled in the art. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A system for advanced treatment of organic wastewater based on Fenton oxidation reaction, characterized in that, The application relates to a Fenton oxidation module, a deep oxidation module, a neutralization and flocculation module and a sedimentation module which are sequentially connected. The Fenton oxidation module and the deep oxidation module are communicated through pipelines, the Fenton oxidation module is provided with a water inlet pipe, a first dosing point and a second dosing point, the first dosing point is used for adding ferrous sulfate, the second dosing point is used for adding hydrogen peroxide, and the deep oxidation module is provided with a third dosing point which is used for adding chlorine dioxide. The deep oxidation module, the neutralization and flocculation module and the sedimentation module are jointly built, and the common walls of adjacent two modules are slotted and communicated. The Fenton oxidation module comprises an oxidation bed, a cyclone water distributor and a solid-liquid separator, the top of the oxidation bed is provided with a water distribution tank, a first dosing tank and a second dosing tank, the water distribution tank is located between the first dosing tank and the second dosing tank and is communicated with the first dosing tank and the second dosing tank, the water distribution tank is provided with the water inlet pipe, the first dosing tank is provided with the first dosing point, and the second dosing tank is provided with the second dosing point.

2. The Fenton oxidation reaction-based advanced treatment system for organic wastewater according to claim 1, characterized in that, The cyclone water distributor and the solid-liquid separator are located in the oxidation bed, the cyclone water distributor is located below the solid-liquid separator, and the first dosing tank and the second dosing tank are respectively communicated with the cyclone water distributor through two circulating stirring pipes. The oxidation bed is internally provided with quartz sand fillers. 3.The Fenton-based oxidation reaction organic wastewater advanced treatment system according to claim 2, characterized in that, The cyclone water distributor comprises a water distribution cover and a water distribution pipe which is in fluid communication with the circulating stirring pipe. 4.The Fenton-based oxidation reaction organic wastewater advanced treatment system according to claim 3, characterized in that, The water distribution cover is in a conical shape with a taper angle upwardly, is located above the water distribution pipe and is provided with a through hole. The deep oxidation module comprises a deep oxidation tank, a first water outlet weir at the top of the oxidation bed is communicated with the deep oxidation tank through a water outlet pipe, and the deep oxidation tank is provided with the third dosing point.

5. The Fenton oxidation reaction-based advanced treatment system for organic wastewater according to any one of claims 2-4, characterized in that, The deep oxidation tank is communicated with the neutralization and flocculation module through a first communication hole in the lower part of the common wall. The bottom of the deep oxidation tank is provided with a first perforated aeration pipe. 6.The Fenton-based oxidation reaction organic wastewater advanced treatment system according to claim 5, characterized in that, The neutralization and flocculation module comprises a neutralization tank and a flocculation tank, the neutralization tank is communicated with the deep oxidation module, the neutralization tank is communicated with the flocculation tank through a second communication hole in the upper part of the common wall.

7. The Fenton oxidation reaction-based advanced treatment system for organic wastewater according to any one of claims 1 to 4, characterized by, The flocculation tank is communicated with the sedimentation module through a third communication hole in the lower part of the common wall. The bottom of the neutralization tank is provided with a second perforated aeration pipe. 8.The Fenton-based oxidation reaction organic wastewater advanced treatment system according to claim 7, characterized in that, The bottom of the flocculation tank is provided with a third perforated aeration pipe, or a stirrer is installed in the flocculation tank. 9.The Fenton-based oxidation reaction organic wastewater advanced treatment system according to claim 8, characterized in that, The sedimentation module comprises a buffer tank and a sedimentation tank, the buffer tank is communicated with the neutralization and flocculation module, the buffer tank is communicated with the sedimentation tank through a fourth communication hole in the middle part of the common wall, a sludge collecting hopper and an inclined plate are installed in the sedimentation tank, the sludge collecting hopper is located at the bottom of the sedimentation tank, and the inclined plate is located between the fourth communication hole and a second water outlet weir of the sedimentation tank in the height direction of the sedimentation tank.

10. The Fenton oxidation reaction-based advanced treatment system for organic wastewater according to any one of claims 1 to 4, characterized by, ​

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