High-phenol wastewater treatment system

Abstract

The utility model provides a high-phenol wastewater treatment system. The high-phenol wastewater treatment system comprises a wet oxidation reactor and a deep oxidation tower, a first mass transfer strengthening unit is arranged outside the wet oxidation reactor, a second mass transfer strengthening unit is arranged in the wet oxidation reactor, the first mass transfer strengthening unit is connected with the second mass transfer strengthening unit, and the second mass transfer strengthening unit is arranged at the middle lower part of the wet oxidation reactor; the bottom end of the deep oxidation tower is connected with the top end of the wet oxidation reactor, and a third mass transfer strengthening unit is arranged in the deep oxidation tower. According to the treatment system disclosed by the utility model, the mass transfer strengthening unit is combined with the reaction system, and wastewater and gas in the wet oxidation reactor are crushed and dispersed into microbubbles through the mass transfer strengthening unit, so that the mass transfer effect between the wastewater and the gas is improved, the reaction efficiency is improved, and the reaction temperature and pressure are reduced at the same time.

Description

Technical Field

[0001] The utility model belongs to the technical field of wastewater treatment, in particular to a system for treating high-phenol wastewater. Background Art

[0002] Phenolic industrial wastewater mainly comes from the petrochemical industry, coking chemical industry, papermaking, pharmaceutical industry, phenolic resin and other industries. Due to the differences in industrial types and production processes, there are significant differences in the types and concentrations of phenolic substances and other pollutants in wastewater. Phenolic compounds pose a serious threat to the environment and human health due to their high biological toxicity. They can react with proteins, causing protein denaturation and inactivation of biological cells. In the human body, high concentrations of phenolic compounds can cause serious local damage, while low concentrations of phenolic compounds may penetrate into the body, causing central nervous system and spinal cord damage, leading to systemic poisoning symptoms. Therefore, phenolic wastewater must be effectively treated and degraded to safety indicators before it can be discharged to reduce the threat to the environment and human health.

[0003] At present, the treatment methods of phenolic wastewater mainly include adsorption, extraction, oxidation and biotechnology. These methods need to be selected according to the phenol concentration and other substance content in the wastewater in practical applications. However, there are many problems with existing treatment technologies. For example, the traditional wet oxidation method needs to be carried out under high temperature and high pressure conditions, and usually a catalyst needs to be added. This method directly oxidizes and degrades organic matter in the wastewater, but has high requirements for equipment, large catalyst loss, and low removal rate of phenolic substances. This leads to high energy consumption, low reaction efficiency, and unsatisfactory treatment effect during the treatment process. Therefore, the development of a phenolic wastewater treatment technology with higher energy efficiency, better reaction efficiency and better treatment effect has become an important demand in the current environmental protection field.

[0004] In view of this, the present utility model is proposed. Utility Model Content

[0005] The purpose of the utility model is to provide a treatment system for high-phenol wastewater, which combines a mass transfer intensification unit with a reaction system. The mass transfer intensification unit is used to break up and disperse the wastewater and gas in a wet oxidation reactor into microbubbles, thereby improving the mass transfer effect between the wastewater and the gas, improving the reaction efficiency, and reducing the reaction temperature and pressure.

[0006] In order to achieve the above-mentioned purpose of the utility model, the following technical solutions are specially adopted:

[0007] The utility model provides a high-phenol wastewater treatment system, comprising:

[0008] Wet oxidation reactors and deep oxidation towers;

[0009] A first mass transfer intensification unit is arranged outside the wet oxidation reactor, and a second mass transfer intensification unit is arranged inside the wet oxidation reactor, the first mass transfer intensification unit is connected to the second mass transfer intensification unit, and the second mass transfer intensification unit is arranged in the middle and lower part of the wet oxidation reactor;

[0010] The bottom end of the deep oxidation tower is connected to the top end of the wet oxidation reactor, and a third mass transfer enhancement unit is arranged in the deep oxidation tower.

[0011] In the prior art, the treatment system of high-phenol wastewater mainly has the following problems: the traditional wet oxidation method needs to be carried out under high temperature and high pressure conditions, and the removal rate of phenolic substances in the wastewater is not high.

[0012] In order to solve the above technical problems, the utility model provides a treatment system for high-phenol wastewater. The treatment system has a simple overall structure and realizes continuous oxidation treatment by integrating a wet oxidation reactor and a deep oxidation tower, thereby greatly enhancing the decomposition efficiency of organic matter, especially high-phenol compounds. The wet oxidation reactor provides preliminary oxidation, while the deep oxidation tower further enhances the oxidation effect, thereby ensuring the thorough treatment of difficult-to-degrade substances.

[0013] By respectively arranging the first mass transfer intensification unit and the second mass transfer intensification unit outside and inside the wet oxidation reactor, the high-phenol wastewater and oxygen entering the wet oxidation reactor can be crushed and dispersed, the gas-liquid two-phase interface mass transfer area can be increased, and the solubility and distribution of oxygen in the liquid phase can be enhanced, thereby accelerating the reaction process; by arranging the third mass transfer intensification unit inside the deep oxidation tower, the gas-liquid two-phase interface mass transfer area in the deep oxidation tower can be increased, the deep oxidation reaction can be promoted, and the reaction temperature and pressure can be reduced at the same time.

[0014] Preferably, the first mass transfer intensification unit includes a first intensified reactor connected to the wastewater storage tank and a second intensified reactor connected to the high-pressure gas pipeline, the first intensified reactor is arranged above the second intensified reactor, and a connecting pipe is arranged between the first intensified reactor and the second intensified reactor.

[0015] The first enhanced reactor of the utility model is arranged above the second enhanced reactor. This is because the first enhanced reactor is connected to a wastewater storage tank and the second enhanced reactor is connected to high-pressure gas. By arranging the first enhanced reactor above the second enhanced reactor, the inertia of the wastewater can be utilized to move downward, and the gas density is lower than that of the wastewater to achieve upward movement of the gas, thereby increasing the gas-liquid contact time and contact area.

[0016] Preferably, an agitator is provided in the communicating pipe, and the agitator is provided at two ports of the communicating pipe.

[0017] Specifically, the agitator in the utility model is a spherical agitator, including a stirring rod and a plurality of stirring wires circumferentially arranged around the stirring rod, the spacing between adjacent stirring wires is equal, and the stirring wires are all arranged in a curved shape.

[0018] The utility model arranges an agitator inside the communicating pipe, and can fully agitate and mix the mixed materials inside the communicating pipe; at the same time, the agitators are respectively arranged at the outlets of the first enhanced reactor and the second enhanced reactor, and can be used in conjunction with the enhanced reactors to timely break and disperse the microbubbles coming out of the enhanced reactors again, so that they are more evenly distributed inside the entire communicating pipe, and at the same time, the agglomeration phenomenon at the outlet of the enhanced reactor is prevented, and the shear force and turbulence are generated by the agitator to prevent or reduce the agglomeration phenomenon, thereby improving the mass transfer efficiency of the system.

[0019] The utility model provides that the spacing between adjacent stirring wires is equal, and the advantage of such a setting is that during the stirring and mixing process of the stirrer, the force on each stirring wire can be uniform, the deformation of the stirring wire can be reduced, and the effect of uniform mixing can be achieved.

[0020] Preferably, the second mass transfer intensification unit includes a third intensified reactor arranged at the bottom end of the wet oxidation reactor, the third intensified reactor is connected to the connecting pipe, and the outlet of the third intensified reactor is provided with a gas-liquid distribution component. The third intensified reactor of the utility model is connected to the connecting pipe, and the mixed material entering the wet oxidation reactor is secondary crushed and dispersed to achieve the effect of full crushing and improve the reaction rate. By providing a gas-liquid distribution component at the outlet of the third intensified reactor, it can be used in conjunction with the third intensified reactor to evenly distribute the microbubbles coming out of the third intensified reactor to the inside of the wet oxidation reactor, thereby maximizing the contact efficiency between gas and liquid, accelerating the transfer and reaction process of the substance; and at the same time improving the utilization rate of the gas.

[0021] Preferably, the gas-liquid distribution assembly comprises a distribution plate and a support grid located above the distribution plate, a plurality of guide plates are connected to the lower surface of the support grid, and the angle between the guide plates and the lower surface of the support grid is 60-90°. Specifically, the guide plates have the same inclination direction.

[0022] Specifically, the distribution plate is connected to the outlet of the third enhanced reactor, and the microbubbles coming out of the third enhanced reactor are evenly diffused in the entire wet oxidation reactor; at the same time, a support grid is arranged above the distribution plate to play a supporting and load-bearing role; by arranging a guide plate under the support grid, the gas-liquid mixing can be enhanced, and by setting the inclination angle of the guide plate, on the one hand, the reaction time can be extended to allow the wastewater and the oxidizing gas to fully mix and react; on the other hand, the mixed materials inside the wet oxidation reactor can be dispersed, the direction of the airflow can be controlled, and the reaction pressure can be reduced.

[0023] Preferably, the second mass transfer enhancement unit further comprises a fourth enhanced reactor disposed in the middle of the wet oxidation reactor, the fourth enhanced reactor is connected to the high-pressure gas pipeline, and an aeration plate is disposed below the outlet of the fourth enhanced reactor. By disposing the fourth enhanced reactor and connecting it to the high-pressure gas pipeline, sufficient gas is filled into the wet oxidation reactor to fully oxidize the wastewater; at the same time, the fourth enhanced reactor is used in conjunction with the aeration plate to provide power for the gas microbubbles coming out of the fourth enhanced reactor, thereby improving the gas conversion rate.

[0024] Preferably, a first defoaming plate, a diffusion plate and a second defoaming plate are sequentially arranged above the second mass transfer intensification unit from bottom to top;

[0025] The first defoaming plate comprises a support plate, a first layer of metal mesh and a second layer of metal mesh from bottom to top.

[0026] By arranging a defoaming plate and a diffusion plate above the second mass transfer intensification unit, most of the foam in the wastewater that will come out of the wet oxidation reactor is eliminated, and the mixed material with a small amount of foam is evenly distributed by the diffusion plate and then eliminated by the upper defoaming plate, and then enters the preheating unit for heat exchange, and then enters the deep oxidation tower for deep oxidation reaction. The advantage of arranging a defoaming plate in the utility model is that it can eliminate large bubbles in the mixed material to avoid uneven heating. The utility model is provided with a diffusion plate between the two defoaming plates, which can cooperate with the two defoaming plates to distribute the gas coming out of the first defoaming plate below more evenly to the second defoaming plate, thereby improving the processing efficiency of the overall system; at the same time, the gas is redistributed and homogenized before entering the second defoaming plate, thereby improving the defoaming efficiency.

[0027] Preferably, the third mass transfer intensification unit includes a fifth intensified reactor arranged at the bottom end of the deep oxidation tower and a sixth intensified reactor arranged above the fifth intensified reactor; the sixth intensified reactor is connected to the gas-liquid mixture coming out of the top of the wet oxidation reactor; and the fifth intensified reactor is connected to the ozone storage tank.

[0028] Preferably, the outlet of the fifth enhanced reactor and the outlet of the sixth enhanced reactor are arranged opposite to each other, and the outlet of the fifth enhanced reactor and the outlet of the sixth enhanced reactor are respectively connected with high-pressure nozzles. In the utility model, a third mass transfer enhancement unit is arranged in the deep oxidation tower, which can further enhance the treatment of refractory organic matter. At the same time, the fifth enhanced reactor of the utility model is connected to the ozone storage tank and arranged at the bottom of the deep oxidation tower. This is to make full use of ozone gas. The fifth enhanced reactor is arranged at the bottom of the reactor, which can increase the reaction time of ozone, thereby fully oxidizing the organic matter in the wastewater and effectively removing the COD content in the wastewater.

[0029] By arranging high-pressure nozzles at the outlets of the fifth and sixth enhanced reactors, the fifth and sixth enhanced reactors can be offset from each other. The high-speed jets from the high-pressure nozzles can form strong turbulence on the microbubbles coming out of the enhanced reactors, thereby promoting full and uniform mixing.

[0030] Preferably, a first heat exchanger and a throttle valve are provided on the connecting pipe connecting the fifth enhanced reactor and the top end of the wet oxidation reactor.

[0031] The utility model can convert the high pressure energy of the high pressure gas-liquid two-phase flow coming out of the wet oxidation reactor into cold energy by setting a throttle valve, so that the temperature in the tower is rapidly reduced, and the high temperature oxidation liquid coming out of the wet oxidation reaction tower can be further cooled, saving energy and reducing energy consumption. At the same time, the utility model adopts a throttle valve as a component for further cooling, and does not require other cold sources for heat exchange, thus saving energy and water.

[0032] Preferably, a circulation pipeline is arranged outside the deep oxidation tower, the inlet of the circulation pipeline is connected to the water outlet at the middle position of the deep oxidation tower, and the outlet of the circulation pipeline is connected to the sixth enhanced reactor;

[0033] Preferably, a second heat exchanger and a circulation pump are provided on the circulation pipeline.

[0034] Those skilled in the art can understand that the enhanced reactor used in the present invention has been embodied in the prior patents of the present invention, such as patents with application numbers CN201610641119.6, CN201610641251.7, CN201710766435.0, CN106187660, CN105903425A, CN109437390A, CN205833127U and CN207581700U. The prior patent CN201610641119.6 describes in detail the specific product structure and working principle of the micron bubble generator (i.e., enhanced reactor). The application document states that "the micron bubble generator includes a main body and a secondary crushing member, a cavity is provided in the main body, an inlet connected to the cavity is provided on the main body, the first and second opposite ends of the cavity are open, wherein the cross-sectional area of ​​the cavity decreases from the middle of the cavity to the first and second ends of the cavity; the secondary crushing member is provided at at least one of the first and second ends of the cavity, a part of the secondary crushing member is provided in the cavity, and an annular channel is formed between the secondary crushing member and the through holes open at both ends of the cavity. The micron bubble generator also includes an air inlet pipe and a liquid inlet pipe." From the specific structure disclosed in the application document, it can be known that its specific working principle is: the liquid enters the micron bubble generator tangentially through the liquid inlet pipe, rotates at ultra-high speed and cuts the gas, so that the gas bubbles are broken into micron-level microbubbles, thereby increasing the mass transfer area between the liquid phase and the gas phase, and the micron bubble generator in the patent belongs to a pneumatic enhanced reactor.

[0035] In addition, the prior patent 201610641251.7 records that the primary bubble breaker has a circulating liquid inlet, a circulating gas inlet and a gas-liquid mixture outlet, and the secondary bubble breaker connects the feed port with the gas-liquid mixture outlet, indicating that the bubble breaker requires gas-liquid mixture to enter. In addition, it can be seen from the following drawings that the primary bubble breaker mainly uses circulating liquid as power, so the primary bubble breaker actually belongs to a hydraulic enhanced reactor, and the secondary bubble breaker simultaneously passes the gas-liquid mixture into an elliptical rotating ball for rotation, thereby achieving bubble breaking during the rotation process, so the secondary bubble breaker actually belongs to a gas-liquid linkage enhanced reactor. In fact, whether it is a hydraulic enhanced reactor or a gas-liquid linkage enhanced reactor, it is a specific form of an enhanced reactor. However, the enhanced reactor adopted by the utility model is not limited to the above-mentioned forms. The specific structure of the bubble breaker recorded in the prior patent is only one of the forms that can be adopted by the enhanced reactor of the utility model.

[0036] In addition, the prior patent 201710766435.0 records that "the principle of the bubble breaker is a high-speed jet to achieve mutual collision of gases", and also explains that it can be used in a micro-interface enhanced reactor, verifying the correlation between the bubble breaker and the micro-interface generator itself; and the prior patent CN106187660 also has relevant records on the specific structure of the bubble breaker, see paragraphs

[0031] -

[0041] in the specification, and the attached drawings, which have a detailed description of the specific working principle of the bubble breaker S-2. The top of the bubble breaker is a liquid phase inlet, and the side is a gas phase inlet. The liquid phase coming in from the top provides suction power, thereby achieving the effect of crushing into ultrafine bubbles. It can also be seen in the attached drawings that the bubble breaker has a conical structure, and the diameter of the upper part is larger than the diameter of the lower part, so that the liquid phase can better provide suction power.

[0037] Since the enhanced reactor was just developed in the early stage of the prior patent application, it was named micron bubble generator (CN201610641119.6), bubble breaker (201710766435.0), etc. in the early stage. With the continuous technical improvement, it was later renamed as enhanced reactor. Now the enhanced reactor in the utility model is equivalent to the previous micron bubble generator, bubble breaker, etc., but the name is different. In summary, the enhanced reactor of the utility model belongs to the prior art.

[0038] Preferably, it also includes a wastewater filter, a preheating unit, an exhaust gas processor, and an ion membrane electrolyzer;

[0039] The wastewater filter is connected to the preheating unit and to the wet oxidation reactor;

[0040] The preheating unit comprises a primary preheater and a secondary preheater connected in sequence, the inlet of the primary preheater is connected to the wastewater filter, and the outlet of the secondary preheater is connected to the first mass transfer enhancement unit, so as to preheat the wastewater;

[0041] The inlet of the secondary preheater is connected to the outlet of the wet oxidation reactor, and the outlet of the primary preheater is connected to the deep oxidation tower;

[0042] The tail gas processor is connected to the top of the deep oxidation tower;

[0043] The ion membrane electrolyzer is connected to the circulation pipeline.

[0044] By setting up a wastewater filter, a preheating unit, an exhaust gas processor and an ion electrolyzer, a complete treatment process is provided for the entire system. Solid impurities are removed through the wastewater filter, and temperature exchange is achieved through the preheating unit to save energy and protect the environment. The exhaust gas is purified by the exhaust gas processor, and the treatment efficiency is further improved by the ion membrane electrolyzer, which not only improves the removal rate of pollutants, but also ensures the environmental friendliness and sustainability of the system.

[0045] Compared with the prior art, the beneficial effects of the utility model are:

[0046] (1) The utility model realizes continuous oxidation treatment by integrating a wet oxidation reactor and a deep oxidation tower, greatly enhancing the decomposition efficiency of organic substances, especially high phenolic compounds; the wet oxidation reactor provides preliminary oxidation, while the deep oxidation tower further enhances the oxidation effect, ensuring the thorough treatment of difficult-to-degrade substances;

[0047] (2) The utility model arranges the enhanced reactor inside the connecting pipe to initially crush and disperse the materials entering the wet oxidation reactor. At the same time, the enhanced reactor is used in conjunction with the agitator to timely crush and disperse the microbubbles coming out of the enhanced reactor again, so that they are more evenly distributed inside the entire connecting pipe;

[0048] (3) The distribution plate of the utility model is used in conjunction with the third enhanced reactor to fully mix the mixed material coming out of the third enhanced reactor and control the direction of the airflow. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those of ordinary skill in the art. The accompanying drawings are only used for the purpose of illustrating the preferred embodiment and are not considered to be limiting of the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0050] Figure 1 A schematic diagram of the structure of a high-phenol wastewater treatment system provided in Example 1 of the utility model;

[0051] Figure 2 A partial enlarged view of the wet oxidation reactor provided in Example 1 of the utility model;

[0052] Figure 3 A schematic diagram of the structure of the agitator provided in Example 1 of the utility model;

[0053] Figure 4 This is a schematic structural diagram of the first defoaming disk provided in Example 1 of the utility model.

[0054] in:

[0055] 1-wet oxidation reactor; 2-first mass transfer enhancement unit;

[0056] 201-first enhanced reactor; 202-second enhanced reactor;

[0057] 203-connecting pipeline; 204-agitator;

[0058] 2041-stirring rod; 2042-stirring wire;

[0059] 3-the second mass transfer enhancement unit; 301-the third enhancement reactor;

[0060] 302- fourth enhanced reactor; 303- gas-liquid distribution component;

[0061] 3031-distribution plate; 3032-support grid;

[0062] 3033-guide plate; 304-aeration plate;

[0063] 305-first defoaming plate; 3051-supporting plate;

[0064] 3052-first layer of metal mesh; 3053-second layer of metal mesh;

[0065] 306-second defoaming disk; 307-diffusion disk;

[0066] 4- Wastewater storage tank; 5- High-pressure gas pipeline;

[0067] 6-deep oxidation tower; 7-third mass transfer enhancement unit;

[0068] 701-fifth enhanced reactor; 702-sixth enhanced reactor;

[0069] 703-high pressure nozzle; 704-first heat exchanger;

[0070] 705-throttle valve; 8-circulation pipeline;

[0071] 801-second heat exchanger; 802-circulation pump;

[0072] 9-wastewater filter; 10-preheating unit;

[0073] 1001- primary preheater; 1002- secondary preheater;

[0074] 11- Exhaust gas processor; 12- Ion membrane electrolyzer. DETAILED DESCRIPTION

[0075] The technical solution of the utility model will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but those skilled in the art will understand that the embodiments described below are part of the embodiments of the utility model, rather than all of the embodiments, and are only used to illustrate the utility model, and should not be considered as limiting the scope of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the utility model. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0076] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0077] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0078] In order to more clearly explain the technical solution of the present invention, it is described in the form of specific embodiments below.

[0079] Example 1

[0080] See also Figure 1-4 As shown, a high-phenol wastewater treatment system provided by an embodiment of the utility model, wherein, referring to Figure 1-2 As shown, the treatment system includes a wet oxidation reactor 1; wherein, a first mass transfer intensification unit 2 is arranged outside the wet oxidation reactor 1, and a second mass transfer intensification unit 3 is arranged inside the wet oxidation reactor 1, the first mass transfer intensification unit 2 is connected to the second mass transfer intensification unit 3, and the second mass transfer intensification unit 3 is arranged in the middle and lower part of the wet oxidation reactor 1.

[0081] Specifically, the first mass transfer intensification unit 2 includes a first intensification reactor 201 connected to the wastewater storage tank 4 and a second intensification reactor 202 connected to the high-pressure gas pipeline 5. The first intensification reactor 201 is arranged above the second intensification reactor 202, and a connecting pipe 203 is arranged between the first intensification reactor 201 and the second intensification reactor 202.

[0082] In a specific embodiment, a stirrer 204 is disposed inside the communication pipe 203, and the stirrer 204 is disposed at two ports of the communication pipe 203. Figure 3 As shown, the agitator 204 in this embodiment is a spherical agitator 204, including a stirring rod 2041 and a plurality of stirring wires 2042 circumferentially arranged around the stirring rod 2041, the spacing between adjacent stirring wires 2042 is equal, and the stirring wires 2042 are all arranged in a curved shape.

[0083] The second mass transfer intensification unit 3 of the utility model includes a third intensified reactor 301 arranged at the bottom end of the wet oxidation reactor 1, the third intensified reactor 301 is connected to the connecting pipe 203, and a gas-liquid distribution component 303 is provided at the outlet of the third intensified reactor 301; specifically, the gas-liquid distribution component 303 includes a distribution plate 3031 and a support grid 3032 located above the distribution plate 3031, and a plurality of guide plates 3033 are connected to the lower surface of the support grid 3032, and the angle between the guide plate 3033 and the lower surface of the support grid 3032 is 60-90°.

[0084] Specifically, according to usage requirements, the inclination angle of the guide plate 3033 is 60°, 65°, 70°, 75°, 80°, 85° or 90°.

[0085] The second mass transfer enhancement unit 3 of the utility model further comprises a fourth enhancement reactor 302 arranged in the middle of the wet oxidation reactor 1 . The fourth enhancement reactor 302 is connected to the high-pressure gas pipeline 5 . An aeration plate 304 is arranged below the outlet of the fourth enhancement reactor 302 .

[0086] In a specific embodiment, the first defoaming plate 305, the diffusion plate 307 and the second defoaming plate 306 are sequentially arranged above the second mass transfer enhancement unit 3 from bottom to top. Figure 4As shown, the first defoaming plate 305 includes, from bottom to top, a support plate 3051, a first metal mesh 3052, and a second metal mesh 3053. The reason why the defoaming plate of the utility model adopts the structural design of the superposition of the support plate 3051 and the metal mesh is that the first metal mesh 3052 and the second metal mesh 3053 can provide a multi-level capture effect, so that large bubbles in the airflow passing through the defoaming plate are effectively intercepted, and at the same time, the first metal mesh 3052 is a large-pore metal mesh, and the second metal mesh 3053 is a small-pore metal mesh. The first metal mesh 3052 captures larger bubbles, and the second metal mesh 3053 captures smaller bubbles. Specifically, the aperture of the small-pore metal mesh is greater than 1 mm.

[0087] Continue reading Figure 1 As shown, the third mass transfer enhancement unit 7 in the utility model includes a fifth enhanced reactor 701 arranged at the bottom of the deep oxidation tower 6 and a sixth enhanced reactor 702 arranged above the fifth enhanced reactor 701; the sixth enhanced reactor 702 is connected to the gas-liquid mixture coming out of the top of the wet oxidation reactor 1; the fifth enhanced reactor 701 is connected to the ozone storage tank; specifically, the outlet of the fifth enhanced reactor 701 and the outlet of the sixth enhanced reactor 702 are arranged oppositely, and the fifth enhanced reactor 701 and the sixth enhanced reactor 702 are arranged on the same straight line, and the outlet of the fifth enhanced reactor 701 and the outlet of the sixth enhanced reactor 702 are respectively connected with a high-pressure nozzle 703. Preferably, the connecting pipe connecting the fifth enhanced reactor 701 and the top of the wet oxidation reactor 1 is provided with a first heat exchanger 704 and a throttle valve 705. The utility model uses the throttle valve 705 as a component for further cooling and depressurization, which can not only convert the higher pressure energy of the high-pressure gas-liquid two-phase flow into cold energy, but also further cool the oxidizing liquid to reach the temperature of deep oxidation.

[0088] A circulation pipeline 8 is arranged outside the deep oxidation tower 6 , the inlet of the circulation pipeline 8 is connected to the water outlet at the middle position of the deep oxidation tower 6 , and a second heat exchanger 801 and a circulation pump 802 are arranged on the circulation pipeline 8 .

[0089] The high-phenol wastewater treatment system of the utility model also includes a wastewater filter 9, a preheating unit 10, a tail gas processor 11 and an ion membrane electrolyzer 12; wherein the wastewater filter 9 is connected to the preheating unit 10 and connected to the wet oxidation reactor 1; the preheating unit 10 includes a primary preheater 1001 and a secondary preheater 1002 connected in sequence, the inlet of the primary preheater 1001 is connected to the wastewater filter 9, and the outlet of the secondary preheater 1002 is connected to the first mass transfer enhancement unit 2, so as to preheat the wastewater; the inlet of the secondary preheater 1002 is connected to the outlet of the wet oxidation reactor 1, and the outlet of the primary preheater 1001 is connected to the deep oxidation tower 6; the tail gas processor 11 is connected to the top of the deep oxidation tower 6; the ion membrane electrolyzer 12 is connected to the circulation pipeline 8.

[0090] The high-phenol wastewater treatment system of the utility model includes the following process flow in practical application:

[0091] After the high-phenol wastewater is filtered through the wastewater filter 9 for solid impurities and phenol condensation macromolecular solid impurities, it is sent to the preheating unit 10. The high-temperature, high-pressure gas-liquid two-phase flow coming out from the top of the wet oxidation reactor 1 exchanges heat with the low-temperature, high-pressure wastewater in the preheating unit 10, fully recovers the wastewater reaction heat energy, and preheats the wastewater at the same time. The preheated wastewater and high-pressure gas are respectively introduced into the first mass transfer enhancement unit 2, and after preliminary crushing and dispersion by the first mass transfer enhancement unit 2, they enter the third enhanced reactor 301 in the wet oxidation reactor 1 for secondary crushing and dispersion. In the wet oxidation reactor 1, the single molecule acetaminophen and most of the phenolic substances in the wastewater are converted into carbon dioxide and small molecule biodegradable substances; the converted wastewater comes out from the top of the wet oxidation reactor 1, enters the preheating unit 10 for heat exchange, and then enters the deep oxidation tower 6 through the throttle valve for further oxidation. The treated oxidizing liquid is sent to the ion membrane electrolyzer 12 to prepare sodium hydroxide and chlorine, and the tail gas from the top of the deep oxidation tower 6 enters the tail gas processor 11 for purification and then discharged.

[0092] Example 2

[0093] The only difference between this example and Example 1 is that the angle between the guide plate and the lower surface of the support grid is 30°.

[0094] Example 3

[0095] The only difference between this example and Example 1 is that the fifth intensified reactor and the sixth intensified reactor are staggered.

[0096] Example 4

[0097] The only difference between this example and Example 1 is that the agitator in the communicating pipe is arranged on the side wall.

[0098] Comparative Example 1

[0099] The only difference between this example and Example 1 is that the first mass transfer intensification unit is not provided.

[0100] Comparative Example 2

[0101] The only difference between this example and Example 1 is that the second mass transfer intensification unit is not provided.

[0102] Comparative Example 3

[0103] The only difference between this example and Example 1 is that the third mass transfer intensification unit is not provided.

[0104] Comparative Example 4

[0105] This example adopts the existing technology to directly pass the high-phenol wastewater into the wet oxidation reactor for decontamination treatment.

[0106] Experimental Example 1

[0107] The treatment systems of Examples 1-4 and Comparative Examples 1-3 were used to treat high-phenol wastewater, respectively. High-phenol wastewater from a chemical plant was treated, wherein the initial pollution indicators in the wastewater were 350 mg / L of phenol content, 500 mg / L of COD content, and 200 mg / L of BOD content. The treated wastewater was tested and the parameters were as follows:

[0108] Table 1 Experimental results

[0109] Phenol content (mg / L) COD content (mg / L) BOD content (mg / L) Example 1 3.5 5 2 Example 2 10.5 20 4 Example 3 17.5 15 8 Example 4 21 25 12 Comparative Example 1 42 50 18 Comparative Example 2 31.5 80 28 Comparative Example 3 56 60 22 Prior art 101.5 120 56

[0110] When the prior art treats high-phenol wastewater, the phenol content in the treated wastewater is 101.5 mg / L, the COD content is 120 mg / L, and the BOD content is 56 mg / L. As can be seen from Table 1, compared with the prior wet oxidation reactor, the phenol content and COD content of the high-phenol wastewater treated by the treatment system of each embodiment of the utility model are significantly reduced, that is, the phenol removal rate and COD removal rate of each embodiment of the utility model are significantly higher than the prior art; and the phenol content, COD content and BOD content of Example 1 are significantly reduced, and the COD removal rate is above 99%.

[0111] As can be seen from Table 1, Example 1 of the utility model is the optimal embodiment. The system of this embodiment arranges the mass transfer enhancement unit inside and outside the wet oxidation reactor respectively, and arranges the mass transfer enhancement unit in the deep oxidation tower. Through the cooperation of various components, the sewage treatment effect of the obtained treatment system is obviously better than the treatment effect of the treatment system in the prior art; at the same time, the phenol content, COD content and BOD content are obviously lower than the phenol content, COD content and BOD content of each embodiment and comparative example, indicating that the mass transfer enhancement unit of Example 1 is used in combination with the entire treatment system to achieve the optimal treatment effect. It can be seen that the treatment system of this embodiment has a good treatment effect.

[0112] Among them, the phenol removal rate and COD removal rate of Comparative Example 1 are lower than those of Example 1. This is because Comparative Example 1 does not have the first mass transfer intensification unit, which cannot break up and disperse the wastewater into micron-level bubbles before the wastewater enters the wet oxidation reactor. Therefore, the wastewater cannot fully react with the high-pressure gas, and the treatment effect of Example 1 of the utility model cannot be achieved. It can be seen that Example 1 of the utility model is designed by setting a mass transfer intensification unit outside the wet oxidation reactor, which improves the treatment effect of the wastewater.

[0113] In conclusion, compared with the prior art, the high-phenol wastewater treatment system of the utility model has higher phenol removal rate, COD removal rate and BOD removal rate, and is worthy of wide promotion and application.

[0114] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. A system for treating high-phenol wastewater, characterized in that: It includes a wet oxidation reactor and a deep oxidation tower; A first mass transfer intensification unit is arranged outside the wet oxidation reactor, and a second mass transfer intensification unit is arranged inside the wet oxidation reactor, the first mass transfer intensification unit is connected to the second mass transfer intensification unit, and the second mass transfer intensification unit is arranged in the middle and lower part of the wet oxidation reactor; The bottom end of the deep oxidation tower is connected to the top end of the wet oxidation reactor, and a third mass transfer enhancement unit is arranged in the deep oxidation tower.

2. The system for treating high-phenol wastewater according to claim 1, characterized in that: The first mass transfer enhancement unit comprises a first enhancement reactor connected to the wastewater storage tank and a second enhancement reactor connected to the high-pressure gas pipeline, the first enhancement reactor is arranged above the second enhancement reactor, and a connecting pipeline is arranged between the first enhancement reactor and the second enhancement reactor; A stirrer is arranged in the communicating pipe, and the stirrer is arranged at two ports of the communicating pipe.

3. The system for treating high-phenol wastewater according to claim 2, characterized in that: The second mass transfer enhancement unit comprises a third enhancement reactor disposed at the bottom end of the wet oxidation reactor, the third enhancement reactor is connected to the connecting pipe, and a gas-liquid distribution component is disposed at the outlet of the third enhancement reactor; The gas-liquid distribution assembly includes a distribution plate and a support grid located above the distribution plate. The lower surface of the support grid is connected to a plurality of guide plates, and the angle between the guide plates and the lower surface of the support grid is 60-90°.

4. The system for treating high-phenol wastewater according to claim 3, characterized in that: The second mass transfer enhancement unit also includes a fourth enhancement reactor arranged in the middle of the wet oxidation reactor, the fourth enhancement reactor is connected to the high-pressure gas pipeline, and an aeration plate is arranged below the outlet of the fourth enhancement reactor.

5. The system for treating high-phenol wastewater according to claim 1, characterized in that: A first defoaming plate, a diffusion plate, and a second defoaming plate are arranged in sequence from bottom to top on the second mass transfer intensification unit; the first defoaming plate includes a support plate, a first layer of metal mesh, and a second layer of metal mesh from bottom to top.

6. The system for treating high-phenol wastewater according to claim 1, characterized in that: The third mass transfer enhancement unit includes a fifth enhanced reactor arranged at the bottom end of the deep oxidation tower and a sixth enhanced reactor arranged above the fifth enhanced reactor; the sixth enhanced reactor is connected to the gas-liquid mixture coming out of the top end of the wet oxidation reactor; the fifth enhanced reactor is connected to the ozone storage tank.

7. The system for treating high-phenol wastewater according to claim 6, characterized in that: The outlet of the fifth enhanced reactor and the outlet of the sixth enhanced reactor are arranged opposite to each other, and the outlet of the fifth enhanced reactor and the outlet of the sixth enhanced reactor are respectively connected with high-pressure nozzles.

8. The system for treating high-phenol wastewater according to claim 6, characterized in that: The connecting pipe connecting the fifth enhanced reactor and the top end of the wet oxidation reactor is provided with a first heat exchanger and a throttle valve.

9. The system for treating high-phenol wastewater according to claim 6, characterized in that: A circulation pipeline is arranged outside the deep oxidation tower, the inlet of the circulation pipeline is connected to the water outlet at the middle position of the deep oxidation tower, and the outlet of the circulation pipeline is connected to the sixth enhanced reactor; The circulation pipeline is provided with a second heat exchanger and a circulation pump.

10. The system for treating high-phenol wastewater according to claim 9, characterized in that: It also includes wastewater filters, preheating units, tail gas processors, and ion membrane electrolyzers; The wastewater filter is connected to the preheating unit and to the wet oxidation reactor; The preheating unit comprises a primary preheater and a secondary preheater connected in sequence, the inlet of the primary preheater is connected to the wastewater filter, and the outlet of the secondary preheater is connected to the first mass transfer enhancement unit, so as to preheat the wastewater; The inlet of the secondary preheater is connected to the outlet of the wet oxidation reactor, and the outlet of the primary preheater is connected to the deep oxidation tower; The tail gas processor is connected to the top of the deep oxidation tower; The ion membrane electrolyzer is connected to the circulation pipeline.

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