Device and method for co-producing steam by utilizing catalytic wet oxidation

Abstract

The invention discloses a device and a method for co-producing steam by utilizing catalytic wet oxidation, a heat removal module is arranged in a reactor of the device, and the heat removal module is provided with a heat exchange cavity, and a heat removal medium inlet and a heat removal medium outlet which are communicated with the heat exchange cavity; and a plurality of channels which are arranged at intervals with the heat exchange cavity and are used for materials in the reactor to flow in the radial direction are arranged on the heat removal module in the thickness direction in a penetrating manner. The heat removal module is arranged in the reactor, reaction heat of the catalytic wet oxidation reaction can be removed in time, it is ensured that the reactor always operates at the constant temperature, the adaptability of the reactor to the TOC content in waste water is greatly improved, and meanwhile the heat removed by the reactor can co-produce steam through the steam generator. The reaction system disclosed by the invention not only can realize catalytic wet oxidation treatment of high-content organic wastewater, but also can realize comprehensive utilization of heat, so that the treatment cost of the wastewater is further reduced.

Description

Technical Field

[0001] The present invention belongs to the field of wastewater treatment, and relates to a device and method for co-producing steam by catalytic wet oxidation, and specifically relates to a device for treating wastewater by catalytic wet oxidation and a method for co-producing steam by utilizing reaction heat during oxidation. Background Art

[0002] Wet oxidation is an effective method for treating toxic and harmful, high-concentration organic wastewater developed in the 1950s. Wet oxidation (WAO) is to use oxidants to oxidize and degrade dissolved or suspended organic matter in wastewater under high temperature and pressure, so as to achieve the purpose of removing pollutants. In the WAO reaction process, organic pollutants are oxidized and decomposed into small molecules that are easy to biodegrade or mineralized into harmless inorganic substances such as carbon dioxide, water and inorganic salts, while sulfur elements in organic pollutants are generally converted into sulfates, halogens into halides, and phosphorus elements into phosphates. Wet oxidation has the characteristics of wide application range, high treatment efficiency, less secondary pollution, fast oxidation rate, and recoverable energy and useful materials. After entering the 1970s, the wet oxidation process has developed rapidly, and its application scope has been further expanded from the recovery of useful chemicals and energy to the treatment of toxic and harmful wastes, especially in the treatment of toxic and harmful substances such as phenol, phosphorus, and cyanide. There are a lot of literature reports. In foreign countries, WAO technology has been industrialized and is mainly used in activated carbon regeneration, cyanide wastewater, coal gasification wastewater, papermaking black liquor, urban sludge and garbage leachate treatment. Domestic research on WAO began in the 1980s, and has successively carried out research on papermaking black liquor, sulfur-containing wastewater, phenol-containing wastewater, coal gasification wastewater, pesticide wastewater and printing and dyeing wastewater.

[0003] However, WAO technology also has certain problems, mainly that it cannot achieve complete mineralization of organic matter, and may produce low molecular weight oxygen-containing compounds (especially acetic acid, propionic acid, methanol, ethanol and acetaldehyde, etc.). In addition, the effect of using WAO to treat structurally stable compounds such as polychlorinated biphenyls is not ideal, so WAO is generally used as a pretreatment step for wastewater containing structurally stable compounds such as polychlorinated biphenyls, and the pretreated wastewater is discharged after biochemical treatment. Therefore, in order to improve the decomposition efficiency of organic matter in the wet oxidation process, people have developed a catalytic wet oxidation treatment method using an efficient and stable catalyst based on the traditional wet air oxidation method. This method uses oxygen-rich gas or oxygen as an oxidant. Under the action of a certain temperature, pressure and catalyst, in order to improve the decomposition efficiency of organic matter in the wet oxidation process, people have developed a catalytic wet oxidation treatment method using an efficient and stable catalyst based on the traditional wet oxidation method. This method uses oxygen-rich gas or oxygen as an oxidant, and utilizes the catalytic effect of the catalyst to reduce the activation energy of the wet oxidation reaction, so as to accelerate the reaction between the organic matter in the wastewater and the oxidant, thereby oxidizing the organic matter and poisons such as N and S in the wastewater into CO2, N2, SO2, and H2O, so as to achieve the purpose of wastewater purification. The catalysts used for wet oxidation treatment can be divided into two types: homogeneous oxidation catalysts and heterogeneous oxidation catalysts.

[0004] In recent years, with the requirements of national industrial policies, the utilization of waste salt (water) resources has continued to increase, thus bringing new application scenarios to the catalytic wet oxidation method. However, the existing catalytic wet oxidation methods all require that the TOC concentration in the wastewater is within a reasonable range. When the TOC concentration in the wastewater is too low, the catalytic wet oxidation reaction needs to supplement a large amount of heat energy; and when the TOC concentration in the wastewater is too high, the release of the heat of the catalytic wet oxidation reaction will cause the reaction temperature to rise, and the increase in reaction temperature will increase the corrosiveness of the material, thereby accelerating the corrosion of the catalytic wet oxidation equipment; at the same time, the increase in temperature will also cause the reaction pressure to rise, causing the entire system to be prone to material leakage, and thus seriously threatening the safety of the catalytic wet oxidation reaction device. At the same time, the reaction heat requires a large amount of circulating water for cooling, which causes a waste of energy, resulting in an increase in the operating cost of the device and a decrease in economic benefits. Summary of the invention

[0005] In order to improve the above technical problems, the present invention provides a catalytic wet oxidation reactor, wherein a heat extraction module is arranged in the reactor.

[0006] According to an embodiment of the present invention, the heat extraction module is concentrically located in the reactor. Preferably, the heat extraction module is coaxially located in the reactor.

[0007] According to an embodiment of the present invention, the outer diameter of the heat extraction module is smaller than the inner diameter of the reactor. Preferably, the ratio of the outer diameter of the heat extraction module to the inner diameter of the reactor is (0.95-1):1.

[0008] According to an embodiment of the present invention, the heat extraction module is provided with a heat exchange cavity and a heat medium inlet and a heat medium outlet connected to the heat exchange cavity, and the heat extraction module is penetrated along the thickness direction with a plurality of channels arranged at intervals from the heat exchange cavity for radial flow of materials in the reactor.

[0009] According to an embodiment of the present invention, the plurality of channels spaced apart from the heat exchange chamber and for allowing radial flow of materials in the reactor are evenly spaced apart.

[0010] According to an embodiment of the present invention, the heat exchange cavity is divided into multiple spaces along the thickness direction, two adjacent spaces are connected through through holes, and the heat medium inlet and the heat medium outlet are respectively connected to the spaces at both ends of the multiple spaces. Preferably, two adjacent through holes are arranged opposite to each other in the radial direction.

[0011] According to an embodiment of the present invention, the total cross-sectional area of ​​all through holes is 0.1%-1% of the cross-sectional area of ​​the heat exchange cavity, exemplified by 0.1%, 0.2%, 0.5%, 0.8% and 1%.

[0012] According to an embodiment of the present invention, the diameter of all through holes may be 2-8 mm, and 5 mm is an example.

[0013] According to an embodiment of the present invention, an inspection channel is further provided in the middle of the heat extraction module. Preferably, a movable cover is provided on the inspection channel. Preferably, the cover is square. For example, the side length of the cover is 500-700 mm.

[0014] The heat extraction module of the present invention takes into account the functions of heat exchange and tray, achieving the purpose of reducing the number of reactor internal parts and saving costs. The heat extraction module is provided with through holes for the axial flow of materials in the reactor from bottom to top, and the materials can also be redistributed to prevent some materials from short-circuiting. In addition, an inspection channel is reserved in the center of the heat extraction module, and the inspection channel adopts a cover plate mode design. When maintenance is required, the cover plate can be opened to facilitate personnel to enter and exit.

[0015] According to an embodiment of the present invention, the reactor is further provided with a gas distributor, which is located at the bottom of the heat extraction module. The gas distributor can generate a large number of bubbles at the millimeter level, which strengthens the mass transfer process during the reaction, is conducive to the formation of more free radicals, and is conducive to the efficient oxidation reaction. Within the same residence time, the TOC content in the wastewater can be effectively reduced to ensure the water outlet index of the reactor.

[0016] According to an embodiment of the present invention, the reactor may be a plurality of reactors arranged in series, or a plurality of heat extraction modules may be axially arranged in a single reactor. Preferably, a plurality of heat extraction modules are axially arranged in the reactor. For example, 1 to 8 heat extraction modules may be axially arranged in the reactor.

[0017] According to an embodiment of the present invention, a plurality of heat extraction modules are evenly spaced axially in the reactor. Preferably, the height distance between two adjacent heat extraction modules is 1800-2200 mm, exemplified by 1800 mm, 1900 mm, 2000 mm, 2100 mm, and 2200 mm.

[0018] Arranging multiple heat extraction modules axially in the reactor can ensure accurate control of the temperature in the reactor, so as to timely adjust the temperature of each section in the reactor according to the reaction effect.

[0019] According to an embodiment of the present invention, the thickness of the heat extraction module is 60-200 mm, and exemplary thicknesses are 60 mm, 80 mm, 100 mm, 120 mm, 150 mm, 180 mm, and 200 mm.

[0020] The heat extraction module of the present invention can be operated under high temperature and high pressure, and the heat extraction module can withstand a high pressure difference on one side, thereby greatly improving the safety of the reaction. At the same time, the heat extraction module used in the present invention can ensure uniform heat extraction in the reactor and ensure a good construction and maintenance environment.

[0021] According to an embodiment of the present invention, the heat extraction medium is preferably a heat transfer medium, such as water or heat transfer oil.

[0022] According to an embodiment of the present invention, the reactor is further provided with a catalyst recovery unit. For example, the catalyst is a catalyst used in a catalytic wet oxidation method known in the art, preferably a catalyst containing copper ions, exemplified by copper chloride.

[0023] According to an embodiment of the present invention, the reactor also includes the elements required for the catalytic wet oxidation reaction. The elements include, but are not limited to, one or more selected from an air inlet unit, an air outlet unit, a feed unit, a discharge unit, and an instrument unit. It should be understood by those skilled in the art that when the reactor is provided with the above-mentioned elements, the elements should not affect the air tightness of the reactor. For this purpose, the elements can be connected to the reactor by welding, flanges and / or pipelines. It should be understood that the structure and function of the elements are known in the art. For example, the air inlet unit and the air outlet unit can be used to pass oxygen and / or air to achieve the catalytic wet oxidation reaction. The feed unit can be used to pass wastewater that needs to be treated, and the discharge unit can be used to discharge reaction products or undesirable residues. The instrument unit can be used to display or monitor the process parameters of the reactor.

[0024] In one embodiment of the present invention, the feed unit comprises a wastewater storage unit and a delivery unit. For example, the wastewater storage unit is a wastewater storage tank; and the delivery unit is a high-pressure pump.

[0025] In one embodiment of the present invention, the instrument unit includes a temperature sensor, a pressure sensor, a TOC online analyzer, an online pH meter, an online copper ion detector and a liquid level sensor. Preferably, the temperature sensor, the pressure sensor and the liquid level sensor are interlocked.

[0026] The present invention also provides a catalytic wet oxidation reaction system, which comprises the above reactor.

[0027] According to an embodiment of the present invention, the reaction system further comprises a preheater and a heater connected in series with the feeding unit, and the outlet of the heater is connected to the feed inlet of the reactor.

[0028] According to an embodiment of the present invention, the reaction system further comprises a steam generator, the inlet of which is connected to the outlet of the heat medium of the heat extraction module. The steam generator of the present invention can realize automatic control of steam pressure, and can realize automatic adjustment of steam flow rate according to the amount of reaction heat obtained. According to an embodiment of the present invention, a distributor is arranged in the steam generator. The steam generator realizes flash evaporation of superheated water to produce steam, and can produce superheated water at the same time. The reaction heat brought by the hot water at the outlet of the heat extraction medium increases the water temperature in the steam generator, and steam is formed after the water temperature increases. When the steam pressure is greater than the preset pressure of the steam generator, the steam is discharged to the steam network through the pipeline. After the steam is discharged, the pressure in the steam generator decreases, and the steam is stopped from being transported to the steam network; when the hot water level in the steam generator is high, hot water can be directly produced from the bottom of the steam generator for use in other devices to further recover heat. The hot water continuously extracts heat from the reactor, causing the temperature of the hot water to increase, which in turn increases the pressure in the steam generator, discharges steam, and so on.

[0029] According to an embodiment of the present invention, the steam generator is provided with a liquid level meter. When the liquid level of water in the steam generator rises, the drain valve is automatically opened to drain the hot water.

[0030] According to an embodiment of the present invention, the steam outlet of the steam generator may be connected to the heat extraction medium inlet of the bottommost heat extraction module in the reactor.

[0031] The heat removed from the reactor can be used to co-produce steam through a steam generator, and part of the co-produced steam can be used to heat the heat medium of the bottom heat extraction module to increase the temperature of the heat extraction medium and then input heat into the reactor, thereby increasing the speed of the wet oxidation reaction to ensure the effect of the wet oxidation reaction.

[0032] According to an embodiment of the present invention, the reaction system further comprises a gas-liquid separation unit (such as a gas-liquid separation tank), and the gas-liquid separation unit is connected to the preheater.

[0033] According to an embodiment of the present invention, the reaction system further comprises a condensing unit, and the condensing unit is connected to the gas outlet of the gas-liquid separation tank.

[0034] According to an embodiment of the present invention, the reaction system further comprises a post-processing unit, which is connected to the liquid outlet of the gas-liquid separation tank, for further refining and recovery of metal ions in wastewater.

[0035] The reactor of the present invention is provided with a safety valve or a bursting disc, etc. If the reactor is at risk of overpressure, the material is automatically discharged into the gas-liquid separation tank, and the high-temperature gas passes through the gas-liquid separation tank and enters the tank top condenser to condense into liquid, which flows into the gas-liquid separation tank by gravity. The liquid in the gas-liquid separation tank is transported to the post-processing unit by a pump for further refining and recovery of metal ions in the wastewater.

[0036] According to an embodiment of the present invention, the reaction system further comprises a tail gas treatment unit, and the tail gas treatment unit is connected to the non-condensable gas outlet of the gas-liquid separation tank.

[0037] In the present invention, the reacted material exits the reactor and passes through a preheater, and after further recovering the waste heat of the material, it enters the gas-liquid separation tank after being depressurized. The material entering the gas-liquid separation tank, and the partially gasified liquid, is condensed by a tank top condensation unit (such as a condenser) at the top of the gas-liquid separation tank and then refluxed into the gas-liquid separation tank, and is pumped to a post-processing unit for further refining and recovery of metal ions in the wastewater. The non-condensable gas is transported to the tail gas treatment unit for treatment.

[0038] According to an embodiment of the present invention, the reaction system further comprises a DCS (Distributed Control System) control system and a SIS (Safety Instrumented System) control system.

[0039] Among them, the DCS control system mainly adjusts the frequency conversion (speed) of the pump through control logic or manual input instructions, thereby adjusting the valve opening, the switch status of the cut-off valve, and controlling the set values ​​of process parameters such as temperature, pressure, liquid level, flow, pH value, copper ion content, and flow. Through the display screen of the DCS control system, the real-time status of each process parameter such as on-site flow, temperature, pressure, liquid level, pH value, copper ion content, and the operating status of rotating equipment can be grasped at all times, so as to grasp the real-time operating parameters on site, and then provide an important basis for production operation adjustments. The SIS system is mainly used as a safety instrument system. The system exists independently of the DCS control system. When the main parameters such as temperature, pressure, and flow exceed the set values, the interlock is automatically triggered to control the device in a safe state.

[0040] According to an exemplary embodiment of the present invention, the DCS control system includes detection instruments, cards (used to collect signals from the detection instruments and output analog or digital signals to actuators), an instrument transmission network and a control station.

[0041] In one embodiment of the present invention, the detection instruments include a thermometer, a pressure gauge and a flow meter.

[0042] In one embodiment of the present invention, a remote thermometer is provided between two adjacent heat extraction modules of the reactor. For example, the remote thermometer can be inserted into the reactor, or an infrared thermometer can be used to detect the temperature of the outer wall of the reactor to monitor the temperature inside the reactor.

[0043] In the present invention, the temperature detected by the thermometer and the heat medium flow rate of the heat extraction module form a control loop, and the flowmeter and the heat medium flow regulating valve of the heat extraction module form a control loop, and finally the heat medium flow rate of two adjacent heat extraction modules in the reactor is regulated, thereby achieving the temperature stability in the reactor. In addition, the DCS control system can control the heat medium flow rate of the heat extraction module under the thermometer through the thermometer, and can also choose to control the heat medium flow rate of the upper heat extraction module, and the heat medium flow rate of two adjacent heat extraction modules can be controlled by selecting the control loop.

[0044] In one embodiment of the present invention, the control station includes an engineer station and an operator station.

[0045] In one embodiment of the present invention, the DCS control system and the SIS control system are also independently provided with an uninterruptible power supply (UPS power supply).

[0046] The present invention also provides a device for co-producing steam by catalytic wet oxidation, which contains the above reaction system.

[0047] The present invention also provides a method for co-producing steam using catalytic wet oxidation, comprising: in the above-mentioned reaction system, subjecting wastewater to a catalytic wet oxidation reaction in a reactor, and utilizing the heat released by the catalytic wet oxidation reaction to co-produce steam in a steam generator.

[0048] The present invention also provides a method for treating wastewater, comprising subjecting the wastewater to a catalytic wet oxidation reaction in the above reactor or reaction system to achieve wastewater purification.

[0049] According to an embodiment of the present invention, the operating temperature of the reactor is between 150-300°C, preferably stabilized at about 280°C.

[0050] According to an embodiment of the present invention, during the catalytic wet oxidation reaction, the pH value of the wastewater is between 0.8 and 1.4, exemplified by 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, and 1.4.

[0051] According to an embodiment of the present invention, the catalyst used in the catalytic wet oxidation reaction may be a catalyst used in a catalytic wet oxidation method known in the art, preferably a catalyst containing copper ions, for example, the copper ion content is between 1000-3000 ppm.

[0052] According to an embodiment of the present invention, the TOC content in the wastewater may be 1000-50000 ppm.

[0053] According to an embodiment of the present invention, in the catalytic wet oxidation reaction, the flow rate at the heat medium inlet is 1 to 3 m / s, exemplified by 1 m / s, 2 m / s, and 3 m / s.

[0054] According to an embodiment of the present invention, in the catalytic wet oxidation reaction, the inlet flow rate of the heat medium outlet is 1 to 3 m / s, exemplified by 1 m / s, 2 m / s, and 3 m / s.

[0055] According to an embodiment of the present invention, in the catalytic wet oxidation reaction, the inlet flow rate of the wastewater is 1-2 m / s, exemplified by 1 m / s, 1.5 m / s, and 2 m / s.

[0056] According to an embodiment of the present invention, in the catalytic wet oxidation reaction, the flow rate of the wastewater in the reactor is 0.05-0.2 m / min, exemplified by 0.05 m / min, 0.1 m / min, 0.15 m / min, and 0.2 m / min.

[0057] According to an embodiment of the present invention, the wastewater may contain mineral salts, mainly sodium chloride salts, and also contain small amounts of phosphates, nitrates, and sulfates. For example, the wastewater may contain sodium chloride. Preferably, the mass fraction of sodium chloride in the wastewater may be as high as 21%.

[0058] Beneficial effects of the present invention:

[0059] (1) The present invention can remove the reaction heat of the catalytic wet oxidation reaction in a timely manner by arranging a heat extraction module inside the reactor to ensure that the reactor is always operated at a constant temperature, thereby greatly improving the adaptability of the reactor to the TOC content in the wastewater. The reactor of the present invention can remove the heat generated when organic wastewater with a high TOC concentration enters the reactor for a catalytic wet oxidation reaction in a timely manner to ensure the safe and stable operation of the reactor. At the same time, the heat removed from the reactor can be used to co-produce steam through a steam generator. A portion of the co-produced steam can be used to heat the wastewater entering the reactor to increase the temperature of the wastewater entering the reactor, and can also be delivered to other users; at the same time, the hot water generated by the steam generator can also be delivered to other users to further recover the heat in the hot water generated by the steam generator. The reaction system of the present invention can not only realize the catalytic wet oxidation treatment of high-content organic wastewater, but also realize the comprehensive utilization of heat, further reducing the treatment cost of wastewater.

[0060] (2) The heat extraction module of the present invention has the characteristics of high heat transfer efficiency, high pressure resistance, and corrosion-resistant materials. At the same time, the present invention makes the temperature in the reactor more stable by arranging a heat extraction module in the reactor, thereby ensuring that the TOC of the wastewater at the outlet of the catalytic wet oxidation reactor reaches the index, and also provides favorable guarantees for the safe and stable operation of the reactor. At the same time, the present invention can automatically control the flow rate of the heat extraction medium of the heat extraction module through the control system to ensure the stability of the temperature in the reactor. The heat extraction medium carries the heat to the steam generator, and the steam generator is designed with pressure automatic control. Its pressure and steam generation form a control loop. When the heat extraction medium carries more heat, the steam generation increases, and the heat brought is removed immediately.

[0061] (3) The heat extraction module of the present invention can also input heat to the reactor. When the temperature in the reactor is low, the steam co-produced by the steam generator can be used to input heat to the heat extraction module to increase the reaction temperature to a suitable reaction temperature, thereby increasing the speed of the wet oxidation reaction to ensure the wet oxidation reaction effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 It is a structural schematic diagram of the wastewater treatment system of the present invention;

[0063] Figure 2 It is a schematic diagram of the structure of the reactor;

[0064] Figure 3 A top view of the heat extraction module;

[0065] Figure 4 is a cross-sectional view of a heat extraction module;

[0066] Figure 5 for Figure 4 A partial enlarged view of part A;

[0067] The reference numerals have the following meanings:

[0068] 1-high pressure pump; 2-preheater; 3-heater; 4-reactor; 5-heat extraction module; 51-heat extraction medium inlet; 52-heat extraction medium outlet; 53-through hole; 54-inspection channel; 55-cover plate; 6-air intake unit; 7-gas distributor; 8-thermal oil pump; 9-steam generator; 10-safety valve; 11-gas-liquid separation tank; 12-tank top condenser; 13-delivery pump; 14-overtemperature cut-off valve; 15-cut-off valve; 16-feeding unit. DETAILED DESCRIPTION

[0069] The technical scheme of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only exemplary descriptions and explanations of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are included in the scope that the present invention is intended to protect.

[0070] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0071] Example 1

[0072] Reference Figure 1 A catalytic wet oxidation reaction system comprises a reactor 4 in which a heat extraction module 5 is arranged.

[0073]

Reactor

[0074] Reference Figure 2 , multiple heat extraction modules 5 are axially arranged in the reactor 4. Preferably, multiple heat extraction modules 5 are axially arranged in the reactor 4. For example, 1-8 heat extraction modules 5 are evenly arranged axially in the reactor 4. Preferably, the height distance between two adjacent heat extraction modules 5 is 1800-2200 mm.

[0075] A plurality of heat extraction modules 5 are axially arranged in the reactor 4 to ensure accurate control of the temperature in the reactor, so as to timely adjust the temperature of each section in the reactor 4 according to the reaction effect.

[0076] The reactor 4 further comprises an air inlet unit 6, an air outlet unit, a feed unit 16, a discharge unit and an instrument unit required for the catalytic wet oxidation reaction.

[0077] In this embodiment, the air inlet unit 6 and the air outlet unit can be used to introduce oxygen and / or air to achieve the catalytic wet oxidation reaction. The feed unit 16 can be used to introduce wastewater to be treated, and the discharge unit can be used to discharge reaction products or undesirable residues. The instrument unit can be used to display or monitor the process parameters of the reactor.

[0078]

Heat extraction module

[0079] Reference Figure 3-5 The heat extraction module 5 is coaxially located in the reactor 4, and the thickness of a single heat extraction module 5 is 60-200 mm, for example, 150 mm; the outer diameter of the heat extraction module 5 is slightly smaller than the inner diameter of the reactor 4. For example, the ratio of the outer diameter of the heat extraction module 5 to the inner diameter of the reactor 4 is infinitely close to 1:1.

[0080] The heat extraction module 5 is provided with a heat exchange cavity and a heat extraction medium inlet 51 and a heat extraction medium outlet 52 connected to the heat exchange cavity, and the heat extraction module 5 is provided with a plurality of channels spaced apart from the heat exchange cavity along the thickness direction for radial flow of materials in the reactor 4. The plurality of channels spaced apart from the heat exchange cavity for radial flow of materials in the reactor 4 are evenly spaced.

[0081] The heat exchange cavity is divided into multiple spaces along the thickness direction, and two adjacent spaces are connected through through holes 53. The heat medium inlet 51 and the heat medium outlet 52 are respectively connected to the spaces at both ends of the multiple spaces. Preferably, two adjacent through holes 53 are arranged opposite to each other in the radial direction.

[0082] The heat extraction medium is preferably a heat transfer medium, such as water or heat transfer oil.

[0083] The heat extraction module 5 can operate under high temperature and high pressure, and can withstand a high pressure difference on one side, thereby greatly improving the safety of the reaction. At the same time, the heat extraction module 5 can ensure uniform heat extraction in the reactor 4 and ensure a good construction and maintenance environment.

[0084]

Through hole

[0085] The diameter of all through holes 53 may be 2-8 mm, and 5 mm is an example.

[0086] The total cross-sectional area of ​​all through holes 53 is 0.1%-1% of the cross-sectional area of ​​the heat exchange chamber, and exemplary examples are 0.1%, 0.2%, 0.5%, 0.8%, and 1%.

[0087]

Inspection channel

[0088] The middle of the heat extraction module 5 is also provided with an inspection channel 54. Preferably, a movable cover plate 55 is provided on the inspection channel 54. Preferably, the cover plate 55 is square. For example, the side length of the cover plate 55 is 500-700 mm.

[0089] The heat extraction module 5 of the present invention takes into account the functions of heat exchange and tray, thereby reducing the number of internal parts of the reactor 4 and saving costs. The heat extraction module 5 is provided with a through hole 53 for the material in the reactor 4 to flow axially from bottom to top, and the material can also be redistributed to prevent some of the material from short-circuiting. A maintenance channel 54 is reserved in the center of the heat extraction module 5. The maintenance channel 54 is designed in the form of a cover plate 55. When maintenance is required, the cover plate 55 is opened to facilitate the entry and exit of personnel.

[0090]

Gas distributor

[0091] The reactor 4 is provided with a gas distributor 7, which is located at the bottom of the lowest heat extraction module 5. The gas distributor 7 can generate a large number of millimeter-level bubbles, which strengthens the mass transfer process during the reaction, is conducive to the formation of more free radicals, and is conducive to the efficient oxidation reaction. Within the same residence time, the TOC content in the wastewater can be effectively reduced to ensure the water outlet index of the reactor 4.

[0092]

Control system

[0093] The catalytic wet oxidation reaction is run under high temperature, high pressure and acidic conditions. In order to ensure the safety of the reaction, the reaction system is also equipped with a DCS (Distributed Control System) control system and a SIS (Safety Instrumented System) control system. The control system can be used to control the flow rate of the catalytic wet oxidation reactor feed wastewater. The frequency conversion of the reactor feed high-pressure pump is controlled by the flow meter of the inlet flow, thereby achieving flow control; the amount of acid added to the catalyst (such as copper chloride) solution is controlled by the pH value of the reactor inlet water to achieve the purpose of adjusting the reactor feed pH value; the amount of catalyst (copper chloride) solution is controlled by detecting the copper ion concentration of the reactor inlet water to achieve the purpose of adjusting the catalyst content in the reactor; the opening of the air intake regulating valve is adjusted by the flow meter of the reactor air intake system, thereby adjusting the flow of oxygen or air entering the reactor; the steam pressure of the heater is controlled to adjust the inlet pressure. The steam flow into the heater is used to control the temperature of the reactor feed wastewater; the pressure gauge installed on the top of the reactor is used to control the opening of the pressure reducing valve before the reactor discharge pipe enters the gas-liquid separation tank to adjust the reactor pressure; multiple thermometers installed axially in the reactor are used to control the heat medium flow of each corresponding heat extraction module in sections to control the reactor temperature. The temperature detected by the thermometer and the heat medium flow of the heat extraction module form a control loop. At the same time, the flowmeter and the heat medium flow regulating valve of the heat extraction module form a control loop, and finally the heat medium flow of the two adjacent heat extraction modules in the reactor is regulated, thereby achieving the temperature stability in the reactor. In addition, the DCS control system can control the heat medium flow of the lower heat extraction module through the thermometer, and can also choose to control the heat medium flow of the upper heat extraction module. The heat medium flow of the two adjacent heat extraction modules can be controlled by selecting the control loop.

[0094] At the same time, the reaction system also has alarms for temperature, pressure, flow, pH value, catalyst concentration, etc. When the first-level alarm is triggered, the DCS control system will issue an audible and visual alarm to remind the operator to intervene and adjust as soon as possible; when the second-level alarm is triggered, the relevant equipment or valve action is interlocked to ensure safety. The instrument unit includes a temperature sensor, a pressure sensor, a TOC online analyzer, an online pH meter, an online copper ion detector and a liquid level sensor. Preferably, the temperature sensor, pressure sensor and liquid level sensor are interlocked.

[0095] When the pressure sensor detects that the pressure in the reactor 4 exceeds the preset pressure, the reaction material is discharged to the gas-liquid separation tank 11 through the safety valve, and the water vapor flashed out of the gas-liquid separation tank 11 passes through the tank top condenser 12 to form a liquid phase and go to the post-processing process; and when the temperature sensor detects that the reactor 4 exceeds the preset reaction temperature, the over-temperature cut-off valve 14 is opened to pass the low-temperature wastewater into the reactor 4 to cool the reactor 4, and at the same time cut off the reactor gas feed valve; when the flow sensor detects that the reactor 4 has a liquid phase interruption, the reactor 4 gas phase inlet pipeline cut-off valve 15 is interlocked and closed to ensure the safety of the reaction. Or when the reactor pressure exceeds the set value, the reactor intake system is forced to stop to achieve the purpose of safe production. The DCS control system and the SIS control system are also independently equipped with UPS power supplies to ensure that the system can also detect and control the device when an unexpected power outage occurs.

[0096] The DCS control system includes detection instruments, cards (used to collect signals from detection instruments and output analog or digital signals to actuators), instrument transmission networks and control stations; detection instruments include thermometers, pressure gauges and flow meters.

[0097]

Feeding unit

[0098] The feed unit 16 includes a wastewater storage unit and a delivery unit. For example, the wastewater storage unit is a wastewater storage tank; and the delivery unit is a high-pressure pump 1 .

[0099] The reaction system further includes a preheater 2 and a heater 3 connected in series with the feed unit 16, and the outlet of the heater 3 is connected with the feed inlet of the reactor 4. The heater 3 can also use external steam to heat the wastewater.

[0100] The feed unit is also provided with a catalyst feed port. For example, the catalyst is a catalyst used in a catalytic wet oxidation method known in the art, preferably a catalyst containing copper ions, exemplified by copper chloride.

[0101] Steam generator

[0102] The reaction system further includes a steam generator 9 , the inlet of the steam generator 9 is connected to the heat medium outlet 52 of the heat extraction module 5 , and the outlet of the steam generator 9 is connected to the heat medium inlet 51 of the bottommost heat extraction module 5 in the reactor 4 .

[0103] The steam generator 9 of the present invention can realize automatic control of steam pressure, and can realize automatic adjustment of steam flow rate according to the amount of reaction heat obtained. The bottom of the reactor 4 is the start-up stage of the reaction, and the heat removed by the reactor can be co-produced with steam through the steam generator 9, and part of the co-produced steam can be used to heat the bottom heat extraction module 5, thereby increasing the speed of the wet oxidation reaction to ensure the effect of the wet oxidation reaction.

[0104] The steam generator 9 realizes flash evaporation of superheated water to produce steam, and can also produce superheated water at the same time. The reaction heat brought by the hot water at the heat medium outlet 52 increases the water temperature in the steam generator 9 to form steam. When the steam pressure is greater than the preset pressure of the steam generator 9, the steam is discharged to the steam network through the pipeline. After the steam is discharged, the pressure in the steam generator 9 decreases, and the steam is stopped from being transported to the steam network. When the hot water level in the steam generator 9 is high, hot water can be directly produced from the bottom of the steam generator 9 for use in other devices to further recover heat. The hot water continuously extracts heat from the reactor, causing the temperature of the hot water to rise, which in turn increases the pressure in the steam generator 9, discharges steam, and repeats this cycle.

[0105] According to an embodiment of the present invention, the steam generator 9 is provided with a liquid level meter. When the liquid level of water in the steam generator 9 rises, the drain valve is automatically opened to discharge the hot water.

[0106]

Reaction waste heat recovery unit

[0107] In the present invention, the high-temperature material after the reaction exits the reactor 4 and passes through the preheater 2, and will exchange heat with the low-temperature material in the preheater 2, so that the temperature of the low-temperature material to be preheated in the preheater is increased, and at the same time the temperature of the material exiting the reactor is reduced, so as to further recover the waste heat of the material, thereby realizing full utilization of the reaction heat energy.

[0108]

Gas-liquid separation unit

[0109] The reaction system also includes a gas-liquid separation tank 11, which is connected to the preheater 2. The reactor 4 of the present invention is provided with a safety valve or a bursting disc, etc. If the reactor 4 is at risk of overpressure, the material is automatically discharged into the gas-liquid separation tank 11, and the high-temperature gas passes through the gas-liquid separation tank 11 and enters the tank top condenser 12 to condense to form a liquid, which flows into the gas-liquid separation tank 11 by gravity. The liquid in the gas-liquid separation tank 11 is transported to the post-processing unit by a pump for further refining and recovery of metal ions in the wastewater.

[0110] In the present invention, the reacted material passes through the preheater after leaving the reactor 4, and after further recovering the waste heat of the material, it enters the gas-liquid separation tank 11 after being depressurized. The material entering the gas-liquid separation tank 11 and the partially gasified liquid are condensed by the condensation unit (such as the top condenser 12) at the top of the gas-liquid separation tank 11 and then refluxed into the gas-liquid separation tank, and are pumped to the post-processing unit for further refining and recovery of metal ions in the wastewater. The non-condensable gas is transported to the tail gas treatment unit for treatment.

[0111]

Condensing unit

[0112] The reaction system further includes a condensing unit, which is connected to the gas outlet of the gas-liquid separation tank 11 .

[0113]

Post-processing unit

[0114] The reaction system further comprises a post-processing unit, which is connected to the liquid outlet of the gas-liquid separation tank 11, and is used for further refining and recovery of metal ions in wastewater.

[0115]

Exhaust gas treatment unit

[0116] The reaction system further comprises a tail gas treatment unit, which is connected to the non-condensable gas outlet of the gas-liquid separation tank 11 .

[0117] The working process of the reaction system of the present invention is as follows: after the catalyst is added to the wastewater containing organic matter, the catalyst concentration and the pH value of the wastewater are adjusted to appropriate indicators, and the high-pressure pump 1 transports the wastewater to be treated to the preheater 2, and the low-temperature wastewater to be treated and the high-temperature wastewater after treatment are heat exchanged in the preheater 2. The high-temperature wastewater after cooling is decompressed by the pressure reducing valve and enters the gas-liquid separation tank 11; the low-temperature wastewater after heat exchange reaches a certain temperature and then enters the heater 3. The heater 3 automatically supplements heat according to the wastewater temperature after preheating and the set heating temperature, and raises the temperature of the wastewater to be treated to the set temperature. The heated wastewater enters the reactor 4, and a certain proportion of high-pressure pure oxygen or a corresponding proportion of air is introduced at the same time. After the gas passes through the gas distributor 7, millimeter-level tiny bubbles are formed to enhance the reaction heat transfer. The hydroxyl radicals formed in the reactor 4 gradually break the organic matter in the wastewater, and form carbon dioxide, water, other salts and a very small amount of small molecular organic matter as the reaction time passes. During the reaction, the heat of reaction is released, and the heat released by the reaction raises the temperature of the material in the reactor 4 to about 270-280°C, which is convenient for the rapid catalytic wet oxidation reaction. When the organic matter content in the reactor 4 is high, more heat will be released. The higher the material temperature, the more severe the corrosion of the material of the reactor 4 will be. At the same time, the reaction pressure in the reactor 4 will also increase, thus bringing safety risks in operation and increasing the operating cost. At this time, the DCS control system sets the temperature between the two adjacent layers of heat extraction modules 5 in the reactor 4 to a suitable temperature. When the temperature rises, the thermometer gives a signal to open the valve opening of the heat extraction medium flow regulating valve through the control logic, increases the flow of the heat extraction medium at the heat extraction medium inlet 51 of the heat extraction module 5, and removes the reaction heat in a timely and uniform manner. The heat extraction medium at the heat extraction medium outlet 52 arrives at the steam generator 9 with heat. The pressure of the steam generator 9 is automatically controlled, and a flow meter and a regulating valve are set at the steam outlet. The produced water pipeline is designed with a flow meter and a regulating valve. Through the steam generation amount, the water extraction flow rate, etc., the pressure of the steam generator 9 is finally controlled, the liquid level is controlled, and the steam flow rate is controlled. A portion of the steam co-produced by the steam generator 9 can be added to the heater 3 to heat the wastewater, and the remaining steam is sent to the pipe network. The wastewater after the reaction enters the preheater 2 for cooling, and the cooled wastewater enters the gas-liquid separation tank 11 after decompression. The water vapor and non-condensable gas in the gas-liquid separation tank 11 enter the tank top condenser 12, and the liquid phase condenses and flows back into the gas-liquid separation tank 11, and the non-condensable gas enters the waste gas treatment unit. The liquid phase in the gas-liquid separation tank 11 is pumped to the post-processing unit for further refining of the metal ions, and finally reaches the point where it can enter the caustic soda device. At the same time, the reactor 4 is also provided with interlocking settings such as temperature, pressure, and liquid interruption.When the pressure in the reactor 4 exceeds the preset pressure, the reaction materials are discharged to the gas-liquid separation tank 11 through the safety valve, and the water vapor flashed out of the gas-liquid separation tank 11 passes through the tank top condenser 12 to form a liquid phase and go to the post-processing process; and when the reactor 4 exceeds the preset reaction temperature, the over-temperature cut-off valve 14 can also be opened to pass low-temperature waste water into the reactor 4 to cool the reactor 4; when the liquid phase is interrupted in the reactor 4, the gas phase inlet pipeline cut-off valve 15 of the reactor 4 is interlocked and closed to ensure the safety of the reaction.

[0118] Example 2

[0119] In the reaction system of Example 1 (wherein: 5 heat extraction modules 5 are evenly arranged in the axial direction of the reactor 4, the heat extraction thickness is 150mm, and the height distance between two adjacent heat extraction modules 5 is 2.2 meters. The heat exchange cavity is divided into multiple spaces along the thickness direction, and two adjacent spaces are connected through through holes 53. The heat extraction medium inlet 51 and the heat extraction medium outlet 52 are respectively connected to the spaces at both ends of the multiple spaces, and two adjacent through holes 53 are arranged radially opposite to each other. The number of all through holes 53 is 1150, and the aperture is 5mm), the flow rate of a certain pesticide wastewater is 25t / h, the wastewater flow rate in the reactor is 0.09m / min, the mass concentration of sodium chloride in the wastewater is 20%, and the wastewater The TOC content is 9000ppm, the inlet temperature of reactor 4 is 230℃, the maximum temperature of reactor 4 is 280℃, the maximum pressure of reactor 4 is 7MPa, the oxygen dosage is 670kg / h, the catalyst used is copper chloride, the catalyst mass concentration is about 1500ppm, the pH value of the wastewater is 1.2, and the organic matter content in the water after the reaction is 6.8ppm. During the reaction, the hot water inlet flow of the heat extraction module 5 is automatically controlled. After the reaction starts, the reactor temperature gradually rises. When the reaction temperature reaches above 280℃, the hot water valve opening of the second heat extraction module 5 from the bottom of the reactor 4 is gradually opened, and the hot water flow rate gradually increases to 3.8m 3 / h, the temperature of hot water rises from 25℃ to 207℃, and finally produces 0.59 tons of 130℃ steam and 3.21 tons of 130℃ hot water; when the reaction temperature reaches above 280℃ again, the hot water valve opening of the third heat extraction module 5 from the bottom of the reactor 4 is gradually opened, the hot water flow rate gradually increases to 1.9m3 / h, the hot water temperature rises from 25℃ to 207℃, and finally produces 0.3 tons of 130℃ steam and 1.6 tons of 130℃ hot water; finally, the temperature of the reactor 4 is stabilized at about 280℃, and the hot water valves of the heat extraction modules 5 above the third one are not opened. After the outlet water of the reactor 4 (TOC content is 6.8ppm) passes through the preheater 2, the temperature is reduced to 80℃, the feed water temperature of the reactor 4 is increased from 30℃ to 200℃, and the heater 3 is introduced with external steam to increase the inlet material temperature of the reactor 4 to 230℃. During the entire reaction process, 0.89 t / h of steam and about 2400 MJ / h of heat were generated by utilizing the reaction heat release; 4.81 tons of 130°C hot water were generated and about 4063 MJ / h of heat were generated; the high-temperature water after the reaction was exchanged with the low-temperature water of the reactor feed, and the waste heat of 14888 MJ / h was utilized again.

[0120] This embodiment saves 21351 MJ / h of heat energy, greatly saves energy, and produces high economic benefits. During the entire operation process, the maximum temperature of the reactor 4 is stable at a preset value, and the heat extraction module operates stably.

[0121] Comparative Example 1

[0122] In the reaction system of Example 1 (wherein: 5 heat extraction modules 5 are evenly spaced axially in the reactor 4, and the height distance between two adjacent heat extraction modules 5 is 2.2 meters. The heat exchange cavity is divided into multiple spaces along the thickness direction, and two adjacent spaces are connected through through holes 53. The heat extraction medium inlet 51 and the heat extraction medium outlet 52 are respectively connected to the spaces at both ends of the multiple spaces. Two adjacent through holes 53 are arranged radially opposite to each other. The number of all through holes 53 is 1150, and the aperture is 5mm. The heat extraction module of reactor 4 was not turned on during this experiment. The flow rate of a certain pesticide wastewater is 25t / h, the flow rate of wastewater in the reactor is 0.09m / min, the mass concentration of sodium chloride in the wastewater is 20%, the TOC content in the wastewater is 9000ppm, and the reaction The inlet temperature of the reactor is 230°C, the maximum temperature of the reactor is 280°C, the maximum pressure of the reactor 4 is 7MPa, the oxygen dosage is 670kg / h, the catalyst used is copper chloride, the catalyst mass concentration is about 1500ppm, the pH value of the wastewater is 1.2, after the reaction starts, the temperature of the reactor 4 rises rapidly to 280°C, in order to ensure the safety of the reaction, the over-temperature cut-off valve 14 is quickly opened to pass the low-temperature wastewater into the reactor 4 at a constant flow rate of 15t / h to cool the reactor 4. Due to the addition of a large amount of low-temperature water, the temperature of the reactor 4 fluctuates, especially the temperature at the bottom of the reactor is as low as below 200°C, resulting in a decrease in the catalytic wet oxidation reaction rate, and the reaction position moves upward, and the final TOC content at the outlet of the reactor 4 is about 703.5ppm.

[0123]

[0124] Example 3

[0125] In the reaction system of Example 1 (wherein: 8 heat extraction modules 5 are evenly spaced in the axial direction in the reactor 4, and the height distance between two adjacent heat extraction modules 5 is 2.0 meters. The heat exchange cavity is divided into multiple spaces along the thickness direction, and two adjacent spaces are connected through through holes 53. The heat extraction medium inlet 51 and the heat extraction medium outlet 52 are respectively connected to the spaces at both ends of the multiple spaces, and two adjacent through holes 53 are arranged radially opposite to each other. The number of all through holes 53 is 1350, and the aperture is 5mm), a chemical wastewater, chlorinated wastewater The mass concentration of sodium is 18%, the TOC content in the wastewater is 13000ppm, the inlet temperature of reactor 4 is 220℃, the maximum temperature of reactor 4 is 280℃, the maximum pressure of reactor 4 is 7MPa, the oxygen consumption is 853kg / h, the catalyst used is copper chloride, the catalyst mass concentration is about 2000ppm, the pH value of the wastewater is 1.0, the water inlet flow rate of reactor 4 is 45t / h, the wastewater flow rate in the reactor is 0.14m / min, and the organic matter content in the water after the reaction is 7.2ppm. After the reaction starts, the temperature of the reactor gradually rises. When the reaction temperature reaches above 280°C, the hot water valve opening of the third heat extraction module 5 from the bottom of the reactor 4 is gradually opened, the hot water flow rate is gradually increased to 3.8m3 / h, the hot water temperature rises from 30°C to 212°C, and finally 0.63 tons of 130°C steam and 3.18 tons of 130°C hot water are generated; the hot water valve opening of the fourth heat extraction module 5 from the bottom of the reactor 4 is gradually opened, the hot water flow rate is gradually increased to 3.0m3 / h, the hot water temperature rises from 30°C to 207°C, and finally 0.47 tons of 130°C steam and 2.53 tons of 130°C hot water are generated; the hot water valve opening of the fifth heat extraction module 5 from the bottom of the reactor 4 is gradually opened, and the hot water flow rate is gradually increased to 1.0m 3 / h, the temperature of hot water rises from 30℃ to 207℃, and finally produces 0.16 tons of 130℃ steam and 0.84 tons of 130℃ hot water; finally, the temperature of reactor 4 is stabilized at about 280℃, and the hot water valve of the heat extraction module 5 above the fifth block is not opened. After the outlet water of reactor 4 (TOC content is 7.2ppm) passes through the preheater 2, the temperature is reduced to 85℃, the feed water temperature of reactor 4 is increased from 35℃ to 202℃, and the external steam is introduced into the heater 3 to increase the inlet material temperature of reactor 4 to 220℃. During the whole reaction process, 1.26t / h of 130℃ steam is generated by reaction exothermicity, generating about 3430MJ / h of heat; 6.55t / h of 130℃ hot water is generated, generating about 5532MJ / h of heat; the high-temperature water after the reaction is heat-exchanged with the low-temperature water of the reactor feed, and the waste heat of 26403MJ is used again.

[0126] This embodiment saves 35365 MJ / h of heat energy. During the entire operation process, the maximum temperature of the reactor is stabilized at a preset value, and the reaction heat extraction system operates stably.

[0127] Comparative Example 2

[0128] In the reaction system of Example 1 (wherein: 8 heat extraction modules 5 are evenly arranged in the axial direction of the reactor 4, and the height distance between two adjacent heat extraction modules 5 is 2.0 meters. The heat exchange cavity is divided into multiple spaces along the thickness direction, and two adjacent spaces are connected through through holes 53. The heat extraction medium inlet 51 and the heat extraction medium outlet 52 are respectively connected to the spaces at both ends of the multiple spaces. Two adjacent through holes 53 are arranged radially opposite to each other. The number of all through holes 53 is 1350, and the aperture is 5mm. During this experiment, the heat extraction module 5 of the reactor 4 was not turned on. A chemical wastewater, the mass concentration of sodium chloride in the wastewater is 18%, the TOC content in the wastewater is 13000ppm, the inlet temperature of the reactor 4 is 220℃, the maximum temperature of the reactor 4 is 280℃, and the maximum pressure of the reactor 4 is 7MPa, oxygen dosage is 853kg / h, copper chloride is used as catalyst, catalyst mass concentration is about 2000ppm, pH value of wastewater is 1.0, water flow rate of reactor 4 is 45t / h, wastewater flow rate in reactor is 0.14m / min, after reaction starts, temperature of reactor 4 rises rapidly to 280℃, in order to ensure reaction safety, over-temperature cut-off valve 14 is opened rapidly to pass low-temperature wastewater into reactor 4 at a constant flow rate of 25t / h to cool down reactor 4. Due to over-temperature too fast, a large amount of low-temperature water is added, resulting in temperature fluctuation of reactor 4, especially the temperature at the bottom of reactor 4 is as low as below 130℃, resulting in reduced catalytic wet oxidation reaction rate, upward movement of reaction position, and finally TOC content at the outlet of reactor 4 is about 3768.2ppm.

[0129]

[0130] The above is an explanation of the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A catalytic wet oxidation reactor, characterized in that: A heat extraction module is arranged in the reactor, and the heat extraction module is concentrically located in the reactor.

2. The catalytic wet oxidation reactor according to claim 1, characterized in that: The heat extraction module is coaxially located in the reactor. Preferably, the outer diameter of the heat extraction module is smaller than the inner diameter of the reactor. Preferably, the ratio of the outer diameter of the heat extraction module to the inner diameter of the reactor is (0.95-1):

1. Preferably, the heat extraction module is provided with a heat exchange cavity and a heat medium inlet and a heat medium outlet connected to the heat exchange cavity, and the heat extraction module is penetrated along the thickness direction with a plurality of channels spaced apart from the heat exchange cavity for radial flow of materials in the reactor. Preferably, the plurality of channels spaced apart from the heat exchange chamber and for radially flowing the material in the reactor are evenly spaced apart. Preferably, the heat exchange cavity is divided into multiple spaces along the thickness direction, two adjacent spaces are connected through through holes, and the heat medium inlet and the heat medium outlet are respectively connected to the spaces at both ends of the multiple spaces. Preferably, two adjacent through holes are arranged opposite to each other in the radial direction. Preferably, the total cross-sectional area of ​​all through holes is 0.1%-1% of the cross-sectional area of ​​the heat exchange chamber. Preferably, the diameter of all through holes may be 2-8 mm. Preferably, an inspection channel is further provided in the middle of the heat extraction module. Preferably, a movable cover is provided on the inspection channel. Preferably, the cover plate is square, for example, the side length of the cover plate is 500-700 mm.

3. The catalytic wet oxidation reactor according to any one of claims 1 to 2, characterized in that: The reactor is also provided with a gas distributor, and the gas distributor is located at the bottom of the heat extraction module. Preferably, a plurality of heat extraction modules are axially arranged in the reactor. For example, 1 to 8 heat extraction modules may be axially arranged in the reactor. Preferably, a plurality of heat extraction modules are evenly spaced in the axial direction in the reactor. Preferably, the height distance between two adjacent heat extraction modules is 1800-2200 mm. Preferably, the thickness of the heat extraction module is 60-200 mm.

4. The catalytic wet oxidation reactor according to any one of claims 1 to 3, characterized in that: The reactor is also provided with a catalyst recovery unit. Preferably, the reactor further comprises one or more of an air inlet unit, an air outlet unit, a feed unit, a discharge unit and an instrument unit required for the catalytic wet oxidation reaction. Preferably, the instrument unit comprises a temperature sensor, a pressure sensor and a liquid level sensor. Preferably, the temperature sensor, the pressure sensor and the liquid level sensor are interlocked.

5. A catalytic wet oxidation reaction system, characterized in that: It contains the reactor according to any one of claims 1 to 4.

6. The reaction system according to claim 5, characterized in that The reaction system also includes a preheater and a heater connected in series with the feed unit, and the outlet of the heater is connected to the feed inlet of the reactor. Preferably, the reaction system further comprises a steam generator, and an inlet of the steam generator is connected to a heat extraction medium outlet of the heat extraction module. Preferably, a distributor is provided in the steam generator. Preferably, the steam generator is provided with a liquid level gauge. Preferably, the outlet of the steam generator is connected to the heat medium inlet of the bottom heat extraction module in the reactor. Preferably, the reaction system further comprises a gas-liquid separation unit, and the gas-liquid separation unit is connected to the preheater. Preferably, the reaction system further comprises a condensing unit, and the condensing unit is connected to the gas outlet of the gas-liquid separation tank. Preferably, the reaction system further comprises a post-processing unit, and the post-processing unit is connected to the liquid outlet of the gas-liquid separation tank. Preferably, the reaction system further comprises a tail gas treatment unit, and the tail gas treatment unit is connected to the non-condensable gas outlet of the gas-liquid separation tank. Preferably, the reaction system further includes a DCS control system and a SIS control system.

7. A device for co-producing steam using catalytic wet oxidation, characterized in that: It contains the reaction system according to any one of claims 5-6.

8. A method for co-producing steam by catalytic wet oxidation, comprising: subjecting wastewater to a catalytic wet oxidation reaction in a reactor in the reaction system as described in any one of claims 5 to 6, and co-producing steam in a steam generator by utilizing the heat released by the catalytic wet oxidation reaction.

9. A method for treating wastewater, characterized in that: The method comprises subjecting wastewater to a catalytic wet oxidation reaction in a reactor as described in any one of claims 1 to 4 or a reaction system as described in any one of claims 5 to 6 to achieve wastewater purification.

10. The method according to claim 9, characterized in that The operating temperature of the reactor is between 150-300°C. Preferably, during the catalytic wet oxidation reaction, the pH value of the wastewater is 0.8-1.

4. Preferably, the catalyst used in the catalytic wet oxidation reaction is a catalyst containing copper ions. Preferably, the copper ion content is between 1000-3000 ppm. Preferably, the TOC content in the wastewater is 1000-50000 ppm. Preferably, in the catalytic wet oxidation reaction, the flow rate at the heat medium inlet is 1 to 3 m / s. Preferably, in the catalytic wet oxidation reaction, the inlet flow rate of the heat medium outlet is 1 to 3 m / s. Preferably, in the catalytic wet oxidation reaction, the inlet flow rate of the wastewater is 1-2 m / s. Preferably, in the catalytic wet oxidation reaction, the flow rate of the wastewater in the reactor is 0.05-0.2 m / min.

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