A gas-liquid-solid circulating fluidized bed reactor and its operation method

Abstract

The present invention provides a gas-liquid-solid circulating fluidized bed reactor and an operating method thereof, wherein the structure of the gas-liquid-solid circulating fluidized bed reactor mainly comprises a fluidized bed reactor (1), a baffled riser (6), a solid-liquid separator (5), a riser recycled water reuse tank (4), a reuse tank control valve (3), a carrier addition port (7), a water outlet tank (8), a water outlet (2), a controller (9), a hydrogen peroxide silo (10), a divalent iron silo (11), a water inlet control valve (12), a divalent iron silo control valve (13), and a hydrogen peroxide silo control valve (14) which are sequentially connected in series. The present invention divides a Fenton oxidation device into components such as a riser, a traditional solid-liquid fluidized bed, and a liquid-solid separator, thereby significantly improving interface contact efficiency, reducing back mixing, enhancing the ability to process a large number of granular carriers, and strengthening the utilization efficiency of iron. The present invention also generates hydrogen peroxide while participating in the process of pollutant autooxidation, thereby reducing the input of reagents.

Description

Technical Field

[0001] The invention relates to a gas-liquid-solid circulating fluidized bed reactor and an operating method thereof, and belongs to the field of difficult-to-degrade sewage treatment. Background Art

[0002] Refractory wastewater contains a variety of organic pollutants that are difficult to treat using traditional biological methods. To treat this type of wastewater, it is generally necessary to reduce its chemical oxygen demand and the molecular weight of the organic matter in the wastewater. Therefore, chemical oxidation methods are usually used. As one of the advanced oxidation methods, the Fenton process involves the application of a mixture of hydrogen peroxide and ferrous ions at an acidic pH to oxidize organic matter. The Fenton reagent is a highly efficient and potent oxidant that can be used to treat various types of organic pollutants. The primary oxidant in the Fenton reagent is the hydroxyl radical (OH·), which is generated by the reaction of hydrogen peroxide with ferrous ions (Fe2+). This highly oxidizing agent can completely render the organic components of the target pollutants harmless, making it widely used in the treatment of refractory wastewater. However, in practical applications, the traditional Fenton oxidation process still has some limitations. For example, as the Fenton reaction proceeds, the H+ decreases and the OH- increases, leading to an increase in pH. In addition, a large amount of iron-containing sludge is produced.

[0003] To leverage the technological advantages of Fenton, fluidized bed reactors are currently commonly used to address the problem of large amounts of iron-containing sludge generated in traditional Fenton reactions. In a fluidized bed Fenton reactor, the iron hydrolysis products can crystallize and grow on the surface of the carrier, undergoing a fluidized bed crystallization reaction. The fluidized bed Fenton crystallization reaction is the process by which ferrous iron is oxidized to ferric iron, forming iron oxides that coat the surface of the filler particles. Current explanations for the crystallization mechanism are primarily based on the metastable region theory, which divides the solubility of Fe(OH)3 into three regions: the unsaturated region, the supersaturated region, and the metastable region, based on the solubility characteristics of ferric iron. Fluidized bed Fenton technology exploits the fact that iron readily undergoes heterogeneous nucleation in the metastable region. By introducing a carrier into the Fenton reaction system, the ferric iron crystallizes on the surface of the carrier particles, thereby reducing the precipitation of iron-containing sludge. However, several currently published patents for fluidized bed Fenton oxidation still face challenges in treatment efficiency and even in the treatment of iron sludge, the core technology.

[0004] According to currently published patents, there are various descriptions of the key module designs of fluidized bed Fenton oxidation devices. However, the engineering applications of each patented device have certain problems, such as: low efficiency of heterogeneous catalysis; problems with the separation, circulation within the device, and uniform distribution of solid fillers; and difficulty in removing filler particles after they have crystallized and grown. A large number of published fluidized bed Fenton patents or articles have also fallen into the misunderstanding of using an adsorptive carrier to adsorb ferrous ions and hydrogen peroxide, and then using the adsorbed carrier as a catalyst to participate in the reaction. As a result, the fluidized bed Fenton only works when the carrier has good adsorption properties. In addition, traditional fluidized bed Fenton oxidation devices generally have defects such as long residence time, uneven water distribution that easily generates channeling, low reagent utilization, and iron removal effects that need to be optimized. Summary of the Invention

[0005] The present invention aims to solve the technical problems commonly found in traditional fluidized bed Fenton oxidation devices, such as long residence time, uneven water distribution that easily generates channeling, low reagent utilization rate, and iron removal effect that needs to be optimized. A gas-liquid-solid circulating fluidized bed reactor and its operation method are proposed.

[0006] The technical solution adopted by the present invention to solve the above problems is: the structure of a gas-liquid-solid circulating fluidized bed reactor proposed by the present invention includes:

[0007] A fluidized bed reactor (1), a water outlet (2), a recycling water tank control valve (3), a recycling water tank (4), a solid-liquid separator (5), a baffled riser (6), a carrier dosing port (7), a water outlet tank (8), a controller (9), a hydrogen peroxide silo (10), a ferrous iron silo (11), a water inlet control valve (12), a ferrous iron silo control valve (13), a hydrogen peroxide silo control valve (14), a gas phase (liquid phase) interface (15), a sewage inlet (16), a fluidized bed reactor sewage inlet (17), a fluidized bed reactor ferrous iron feed port (18), a fluidized bed reactor hydrogen peroxide feed port (19), an inclined pipe (20) for solid phase to enter the baffled riser, an inclined pipe (21) for solid phase to enter the fluidized bed reactor, a gas phase outlet (22), a particle carrier unloading port (23), a pH control device (24), and an inclined pipe (25) for diversion to enter the baffled riser;

[0008] The fluidized bed reactor (1), the baffled riser (6), the solid-liquid separator (5), the riser regenerated water reuse tank (4), the reuse tank control valve (3), the carrier addition port (7), the outlet water tank (8), the outlet port (2), the controller (9), the hydrogen peroxide silo (10), the divalent iron silo (11), the water inlet control valve (12), the divalent iron silo control valve (13), and the hydrogen peroxide silo control valve (14) are sequentially connected in series.

[0009] Optionally, the water inlet (16) is connected to the controller (9) via the water inlet control valve (12); the hydrogen peroxide silo (10) and the ferrous iron silo (11) are connected to the controller (9) via the ferrous iron silo control valve (13) and the hydrogen peroxide silo control valve (14); the controller (9) is connected to the fluidized bed reactor (1) via the fluidized bed reactor hydrogen peroxide feed port (19) and the fluidized bed reactor sewage water inlet (17); the controller (9) is connected to the fluidized bed reactor (1) and the recycled water tank control valve (3) via the fluidized bed reactor ferrous iron feed port (18);

[0010] The top of the fluidized bed reactor (1) is provided with a carrier addition port (7) and is connected to a water outlet tank (8) and a water outlet (2). A pH control device (24) is connected to the left side. The fluidized bed reactor (1) is connected to the baffled vertical pipe (6) through an inclined pipe (20) for solid phase to enter the baffled vertical pipe. The water inlet at the bottom end of the baffled vertical pipe (6) is connected to the controller (9) through an inclined pipe (25) for diverting into the baffled vertical pipe. A gas phase (liquid phase) interface (15) is provided on the right side of the baffled vertical pipe (6). A solid-liquid separator (5) is provided at the top of the vertical pipe (6), a gas phase outlet is provided on the side of the solid-liquid separator (5), and a particle carrier unloading port (23) and a gas phase outlet (22) are provided at the top and right side of the solid-liquid separator (5), respectively. The solid phase product of the solid-liquid separator (5) enters the fluidized bed reactor through the inclined pipe (21) of the solid phase and returns to the fluidized bed reactor (1), and the liquid phase product of the solid-liquid separator (5) returns to the fluidized bed reactor (1) through the recycling water tank (4) and the recycling water tank control valve (3).

[0011] Optionally, the diameter of the fluidized bed reactor (1) is larger than that of the baffled riser (6), and a plurality of baffles (601) are provided in the baffled riser (6).

[0012] A method for operating a gas-liquid-solid circulating fluidized bed reactor, comprising:

[0013] Step 1.1: The sewage to be treated passes through the sewage inlet (16) and is regulated by the controller (9). The sewage to be treated enters the fluidized bed reactor (1) from the sewage inlet (17) of the fluidized bed reactor. The controller (9) regulates the hydrogen peroxide silo (10) and the divalent iron silo (11) respectively to add hydrogen peroxide and iron salt to the fluidized bed reactor (1). The divalent iron in the iron salt reacts with the hydrogen peroxide to generate hydroxyl radicals and trivalent iron. The hydroxyl radicals oxidize the difficult-to-degrade pollutants in the sewage to be treated. The trivalent iron crystallizes on the carrier particles from top to bottom. The effluent enters the effluent tank (8) and is discharged through the outlet (2) after being tested and meeting the standards.

[0014] Step 1.2: The crystallized carrier particles enter the baffled riser from the solid phase through the inclined tube (20) and then enter the baffled riser (6). The hydrogen peroxide is diverted by the controller (9) and then enters the baffled riser (6) through the inclined tube (25) entering the baffled riser. The crystals on the carrier particles react with the hydrogen peroxide to generate divalent iron and peroxyhydroxyl radicals. The peroxyhydroxyl radicals continue to react with the crystals on the carrier to generate divalent iron and oxygen. The divalent iron, peroxyhydroxyl radicals and oxygen generated by the reaction are transported to the solid-liquid separator (5).

[0015] Step 1.3: In the solid-liquid separator (5), the oxygen generated by the reaction and the oxygen generated by the self-decomposition of hydrogen peroxide are recovered. The liquid phase product is separated and returned to the fluidized bed reactor (1) through the recycling water tank control valve (3) and the recycling water tank (4) to participate in the Fenton reaction and wash away the crystals on the solid phase product;

[0016] Step 1.4: The solid phase product after elution and crystallization is transported to the fluidized bed reactor (1) through the inclined tube (21) of the solid phase fluidized bed reactor for reuse.

[0017] Optionally, the step of performing a Fenton reaction on the tryptone wastewater includes:

[0018] Step 2.1: The tryptone wastewater to be treated is passed through the wastewater inlet (16) and, under the control of the controller (9), enters the fluidized bed reactor (1) from the wastewater inlet (17) of the fluidized bed reactor. The controller (9) controls the hydrogen peroxide silo (10) and the divalent iron silo (11) to add hydrogen peroxide and iron salt to the fluidized bed reactor (1);

[0019] Step 2.2: The divalent iron in the iron salt reacts with hydrogen peroxide to generate hydroxyl radicals and trivalent iron. The hydroxyl radicals oxidize the difficult-to-degrade pollutants in the tryptophan wastewater to be treated. The trivalent iron crystallizes on the carrier particles from top to bottom. The crystallized carrier particles enter the inclined tube (20) of the baffled riser through the solid phase and enter the baffled riser (6). Step 2.2 is repeated 3-5 times.

[0020] Step 2.3: After 3-5 cycles, the tryptophan wastewater to be treated is diverted under the control of the controller (9). The diverted tryptophan wastewater to be treated is mixed with the hydrogen peroxide solution and enters the baffled riser (6) through the inclined tube (25) that enters the baffled riser. The crystals on the carrier particles react with the hydrogen peroxide to generate divalent iron and peroxyhydroxyl radicals. The peroxyhydroxyl radicals continue to react with the crystals on the carrier to generate divalent iron and oxygen. The tryptophan substances in the tryptophan wastewater to be treated also react with the peroxyhydroxyl radicals. Step 2.3 is repeated until the treated alcohol wastewater meets the discharge standard.

[0021] Step 2.4: The divalent iron, peroxyhydroxyl radicals and oxygen generated by the reaction are transported to the solid-liquid separator (5), and the oxygen generated by the reaction and the oxygen generated by the self-decomposition of hydrogen peroxide are recovered. The liquid phase product is separated and returned to the fluidized bed reactor (1) through the recycling water tank control valve (3) and the recycling water tank (4) to participate in the Fenton reaction and wash away the crystals on the solid phase product;

[0022] Step 2.4: The solid phase product after elution and crystallization is transported to the fluidized bed reactor (1) through the inclined tube (21) of the solid phase fluidized bed reactor for reuse.

[0023] Optionally, during the operation of the gas-liquid-solid circulating fluidized bed reactor, the pH control device (24) controls the pH value of the fluidized bed reactor (1) to be between 3 and 4.

[0024] Optionally, the molar ratio of the total molar amount of divalent iron to hydrogen peroxide in the fluidized bed reactor (1) is (1:1)-(1:1.12), and the concentration of hydrogen peroxide is more than 30%.

[0025] Optionally, the carrier particles are coarse building sand particles, the particle size of which is distributed in the range of 0.5-5 mm and the particle density is 300-500 kg / m 3 .

[0026] The beneficial effects of the present invention are:

[0027] The present invention is divided into the components such as riser, traditional solid-liquid fluidized bed and liquid-solid separator by Fenton oxidation device, significantly improves interface contact efficiency, reduces back mixing, strengthens the ability of processing a large amount of particle carriers, strengthens the utilization efficiency to iron. In addition, for processing the sewage containing a large amount of tryptophan substances medicines, the present invention also generates hydrogen peroxide while participating in the process of pollutant autooxidation, reduces the input of medicament. The present invention avoids the generation of iron mud, alleviates the back mixing effect and the carrier treatment problem that traditional fluidized bed reactor brings, and simultaneously in the treatment process for containing specific class pollutant wastewater, not only improves the removal efficiency of pollutants but also reduces the input of medicament, can long-term circulation operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a structural diagram of a gas-liquid-solid circulating fluidized bed reactor provided by the present invention;

[0029] Figure 2 A flow chart of an operating method of a gas-liquid-solid circulating fluidized bed reactor provided by the present invention;

[0030] In the figure, 1-fluidized bed reactor, 2-water outlet, 3-recycled water tank control valve, 4-recycled water tank, 5-solid-liquid separator, 6-baffled riser, 7-carrier feeding port, 8-water outlet tank, 9-controller, 10-hydrogen peroxide silo, 11-ferrous iron silo, 12-water inlet control valve, 13-ferrous iron silo control valve, 14-hydrogen peroxide silo control valve, 15-gas phase (liquid phase) interface, 16-sewage inlet, 17-fluidized bed reactor sewage inlet, 18-fluidized bed reactor ferrous iron feed port, 19-fluidized bed reactor hydrogen peroxide feed port, 20-inclined pipe for solid phase to enter the baffled riser, 21-inclined pipe for solid phase to enter the fluidized bed reactor, 23-granular carrier unloading port, 24-pH control device and 25-inclined pipe for diversion to enter the baffled riser. DETAILED DESCRIPTION

[0031] Specific implementation method 1: Combination Figure 1 This embodiment describes a gas-liquid-solid circulating fluidized bed reactor having the following structure:

[0032] The invention relates to a fluidized bed reactor (1), a baffled riser (6), a solid-liquid separator (5), a riser regenerated water reuse tank (4), a reuse tank control valve (3), a carrier addition port (7), a water outlet tank (8), a water outlet (2), a controller (9), a hydrogen peroxide silo (10), a ferrous iron silo (11), a water inlet control valve (12), a ferrous iron silo control valve (13), and a hydrogen peroxide silo control valve (14) which are sequentially connected in series.

[0033] The water inlet (16) is connected to the controller (9) through the water inlet control valve (12), the hydrogen peroxide silo (10) and the divalent iron silo (11) are connected to the controller (9) through the divalent iron silo control valve (13) and the hydrogen peroxide silo control valve (14), the controller (9) is connected to the fluidized bed reactor (1) through the fluidized bed reactor hydrogen peroxide feed port (19) and the fluidized bed reactor sewage water inlet (17), the controller (9) is connected to the fluidized bed reactor (1) and the recycled water tank control valve (3) through the fluidized bed reactor divalent iron feed port (18), the top of the fluidized bed reactor (1) is provided with a carrier addition port (7) and is connected to the water outlet tank (8) and the water outlet (2), the left side is connected to the pH control device (24), the fluidized bed reactor (1) is connected to the solid The inclined pipe (20) for the phase to enter the baffled riser is connected to the baffled riser (6); the water inlet at the bottom end of the baffled riser (6) is connected to the controller (9) through the inclined pipe (25) for entering the baffled riser via the diversion; a gas phase (liquid phase) interface (15) is provided on the right side of the baffled riser (6); a solid-liquid separator (5) is provided on the top of the baffled riser (6); a gas phase outlet is provided on the side of the solid-liquid separator (5); a particle carrier unloading port (23) and a gas phase outlet (22) are provided on the top and right side of the solid-liquid separator (5), respectively; the solid phase product of the solid-liquid separator (5) returns to the fluidized bed reactor (1) through the inclined pipe (21) for the solid phase to enter the fluidized bed reactor; and the liquid phase product of the solid-liquid separator (5) returns to the fluidized bed reactor (1) through the recycling water tank (4) and the recycling water tank control valve (3).

[0034] The diameter of the fluidized bed reactor (1) is larger than that of the baffled riser (6). The reaction and flow rate in the fluidized bed reactor (1) are relatively slow to achieve the effects of fluidization and pollutant treatment. A plurality of baffles (601) are provided in the baffled riser to enable the reaction to proceed fully.

[0035] Specific implementation method 2: Combination Figure 2 This embodiment is described as follows. Figure 2 The operating method of a gas-liquid-solid circulating fluidized bed reactor described in this embodiment includes the following steps:

[0036] S1: The sewage to be treated is introduced from the water inlet (16) and enters the fluidized bed reactor (1) through the sewage inlet (17) of the fluidized bed reactor under the control of the controller (9). Hydrogen peroxide and iron salt are respectively added to the fluidized bed reactor (1) through the inclined pipe (25) of the baffled riser in appropriate amounts from the hydrogen peroxide silo (10) and the divalent iron silo (11) under the control of the controller (9). As the water flows upward, the divalent iron reacts with the hydrogen peroxide to generate hydroxyl radicals, which oxidize the difficult-to-degrade pollutants in the sewage. In addition, the generated trivalent iron crystallizes on the carrier particles from top to bottom, and the effluent enters the effluent tank (8). After being tested and meeting the standards, it is discharged through the outlet (2).

[0037] S2: The crystallized carrier enters the baffled riser through the solid phase and the inclined tube (20) and enters the baffled riser (6). Hydrogen peroxide is fed into the baffled riser (6) through the water inlet. In the reactor, the crystals on the carrier particles react with hydrogen peroxide to generate divalent iron and peroxyhydroxyl radicals. The peroxyhydroxyl radicals continue to react with the crystals on the carrier to generate divalent iron and oxygen. The solid and liquid phase products are passed into the solid-liquid separator (5).

[0038] S3: In the solid-liquid separator (5), the oxygen generated by the reaction and the self-decomposition of hydrogen peroxide is directly recovered, and the liquid phase product is separated and returned to the fluidized bed reactor (1) through the recycling water tank (4) and the recycling water tank control valve (3) to participate in the Fenton reaction.

[0039] S4: After the reaction in S2, the crystallized carrier particles are washed away, i.e., the solid phase product enters the inclined tube (21) of the fluidized bed reactor through the solid phase after separation and returns to the fluidized bed reactor (1) 1 for reuse.

[0040] The original baffled riser (6) separates the homogeneous reaction (i.e., the reaction of divalent iron with HOOH to generate hydroxyl radicals, which oxidize organic pollutants and crystallize on the carrier) from the heterogeneous reaction (i.e., the reaction of iron on the carrier with HOOH to generate hydroperoxyl radicals, which continue to react with iron crystals on the carrier and generate gas), that is, the treatment of organic pollutants is completed in the traditional fluidized bed area, and the reduction of iron crystals and the reuse of the carrier are completed in the riser area, and the influence of back mixing in the traditional fluidized bed is also avoided.

[0041] The crystallized carrier is eluted and reused in the baffled vertical pipe (6), and its circulation speed is represented by the fluidization speed of the particle carrier in the fluidized bed reactor (6) and the baffled flow speed of the baffled vertical pipe (6).

[0042] According to construction standards, construction sand refers to particles with a particle size of less than 5 mm, or can be construction particles with a particle size of less than 4.75 mm processed by mining machinery. The average particle size of coarse sand is above 0.5 mm, so the particle carrier used in the reaction system of the present invention is coarse construction sand particles, with a particle size distribution of 0.5-5 mm and a particle density of 300-500 kg / m 3 .

[0043] The molar ratio of the total molar amount of ferrous iron in the fluidized bed reactor 1 (and the amount added to the silo 11 and the total amount of recycled water in the water tank 4) to hydrogen peroxide should be (1:1)-(1:1.2), and the concentration of hydrogen peroxide should be controlled at more than 30%.

[0044] Specific implementation method three, combined with Figure 2 This embodiment is described as follows. Figure 2 As shown, the operating method of a gas-liquid-solid circulating fluidized bed reactor described in this embodiment includes the following steps:

[0045] S1: The sewage to be treated is introduced from the water inlet (16) and enters the fluidized bed reactor (1) through the sewage inlet (17) of the fluidized bed reactor under the control of the controller (9). Hydrogen peroxide and iron salt are respectively added from the hydrogen peroxide silo (10) and the divalent iron silo (11) under the control of the controller (9) and added to the fluidized bed reactor (1) in appropriate amounts through the inclined tube (25) of the baffled riser. As the water flow rises, the divalent iron reacts with the hydrogen peroxide to generate hydroxyl radicals, which oxidize the difficult-to-degrade pollutants in the sewage. In addition, the generated trivalent iron crystallizes on the carrier particles from top to bottom, enters the inclined tube (20) of the baffled riser through the solid phase, and enters the baffled riser (6). This cycle is repeated for 3-5 times.

[0046] S2: The alcohol wastewater to be treated is diverted under the control of the controller (9), mixed with the hydrogen peroxide solution, and passed into the baffled riser (6) through the inclined tube (25) of the baffled riser. In the reactor, the crystals on the carrier particles react with the hydrogen peroxide to generate divalent iron and peroxyhydroxyl radicals. The peroxyhydroxyl radicals continue to react with the crystals on the carrier to generate divalent iron and oxygen. The alcohol substances also react with the peroxyhydroxyl radicals to generate hydrogen peroxide. The solid and liquid products are passed into the solid-liquid separator (5). The cycle is then repeated until the treated alcohol wastewater meets the discharge standard.

[0047] S3: In the solid-liquid separator (5), the oxygen generated by the reaction and the self-decomposition of hydrogen peroxide is directly recovered, and the liquid phase product is separated and returned to the fluidized bed reactor (1) through the water tank (4) and the return water tank control valve (3) to participate in the Fenton reaction.

[0048] S4: After the crystallized carrier particles are washed away by the reaction in S2, the solid phase product is separated and then sent back to the fluidized bed reactor (1) through the inclined tube (21) of the fluidized bed reactor for reuse.

[0049] The original baffled riser (6) separates the homogeneous reaction (i.e., the reaction of divalent iron with HOOH to generate hydroxyl radicals, which oxidize organic pollutants and crystallize on the carrier) from the heterogeneous reaction (i.e., the reaction of iron on the carrier with HOOH to generate hydroperoxyl radicals, which continue to react with iron crystals on the carrier and generate gas), that is, the treatment of organic pollutants is completed in the traditional fluidized bed area, and the reduction of iron crystals and the reuse of the carrier are completed in the riser area, and the influence of back mixing in the traditional fluidized bed is also avoided.

[0050] The crystallized carrier is eluted and reused in the baffled vertical pipe (6), and its circulation speed is represented by the fluidization speed of the particle carrier in the fluidized bed reactor (6) and the baffled flow speed of the baffled vertical pipe (6).

[0051] According to construction standards, construction sand refers to particles with a particle size of less than 5 mm, or can be construction particles with a particle size of less than 4.75 mm processed by mining machinery. The average particle size of coarse sand is above 0.5 mm, so the particle carrier used in the reaction system of the present invention is coarse construction sand particles, with a particle size distribution of 0.5-5 mm and a particle density of 300-500 kg / m 3 .

[0052] The molar ratio of the total molar amount of ferrous iron in the fluidized bed reactor 1 (and the amount added to the silo 11 and the total amount of recycled water in the water tank 4) to hydrogen peroxide should be (1:1)-(1:1.2), and the concentration of hydrogen peroxide should be controlled at more than 30%.

[0053] In summary, according to the operating procedures of the above-described embodiments, the present invention can significantly improve interfacial contact efficiency, reduce back-mixing, enhance the ability to process large amounts of particulate carriers, and enhance the efficiency of iron utilization. Furthermore, it avoids the generation of iron sludge, alleviates the back-mixing effect and carrier handling issues associated with traditional fluidized bed reactors, and simultaneously improves pollutant removal efficiency and reduces reagent input in the treatment process for wastewater containing specific types of pollutants, enabling long-term cyclic operation.

[0054] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the present profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical content disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent replacement and improvement of the above embodiments made according to the technical essence of the present invention, within the spirit and principles of the present invention, without departing from the content of the technical solution of the present invention, shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A gas-liquid-solid circulating fluidized bed reactor, characterized in that: The structure of the gas-liquid-solid circulating fluidized bed reactor comprises: Fluidized bed reactor (1), water outlet (2), recycling water tank control valve (3), recycling water tank (4), solid-liquid separator (5), baffled riser (6), carrier feeding port (7), water outlet tank (8), controller (9), hydrogen peroxide silo (10), ferrous iron silo (11), water inlet control valve (12), ferrous iron silo control valve (13), hydrogen peroxide silo control valve (14), gas phase / liquid phase interface (15), sewage inlet (16), fluidized bed reactor sewage inlet (17), fluidized bed reactor ferrous iron feed port (18), fluidized bed reactor hydrogen peroxide feed port (19), inclined tube (20) for solid phase to enter baffled riser, inclined tube (21) for solid phase to enter fluidized bed reactor, gas phase outlet (22), particle carrier unloading port (23), pH control device (24) and inclined tube (25) for diversion to enter baffled riser; The sewage inlet (16) is connected to the controller (9) via the water inlet control valve (12); the hydrogen peroxide silo (10) and the ferrous iron silo (11) are connected to the controller (9) via the ferrous iron silo control valve (13) and the hydrogen peroxide silo control valve (14); the controller (9) is connected to the fluidized bed reactor (1) via the fluidized bed reactor hydrogen peroxide feed port (19) and the fluidized bed reactor sewage inlet (17); the controller (9) is connected to the fluidized bed reactor (1) and the recycled water tank control valve (3) via the fluidized bed reactor ferrous iron feed port (18); The top of the fluidized bed reactor (1) is provided with a carrier addition port (7) and is connected to the water outlet tank (8) and the water outlet (2). A pH control device (24) is connected to the left side. The fluidized bed reactor (1) is connected to the baffled riser (6) through an inclined pipe (20) for the solid phase to enter the baffled riser. The water inlet at the bottom end of the baffled riser (6) is connected to the controller (9) through an inclined pipe (25) for the baffled riser to enter the baffled riser. A gas / liquid phase interface is provided on the right side of the baffled riser (6). (15), a solid-liquid separator (5) is provided on the top of the baffled riser (6), and a particle carrier unloading port (23) and a gas phase outlet (22) are provided at the top and right side of the solid-liquid separator (5), respectively. The solid phase product of the solid-liquid separator (5) enters the fluidized bed reactor through the inclined pipe (21) of the solid phase and returns to the fluidized bed reactor (1), and the liquid phase product of the solid-liquid separator (5) returns to the fluidized bed reactor (1) through the return water tank (4) and the return water tank control valve (3); The fluidized bed reactor (1), the baffled riser (6), the solid-liquid separator (5), the recycled water tank (4), the recycled water tank control valve (3), the carrier addition port (7), the water outlet tank (8), the water outlet (2), the controller (9), the hydrogen peroxide silo (10), the ferrous iron silo (11), the water inlet control valve (12), the ferrous iron silo control valve (13), and the hydrogen peroxide silo control valve (14) are sequentially connected in series.

2. A gas-liquid-solid circulating fluidized bed reactor according to claim 1, characterized in that: The diameter of the fluidized bed reactor (1) is larger than that of the baffled riser (6), and the baffled riser (6) is provided with a plurality of baffles (601).

3. A method for operating a gas-liquid-solid circulating fluidized bed reactor, applied to a gas-liquid-solid circulating fluidized bed reactor according to any one of claims 1 to 2, characterized in that: include: The Fenton reaction is carried out on sewage and tryptophan-type sewage based on a gas-liquid-solid circulating fluidized bed reactor, wherein the steps of carrying out the Fenton reaction on the sewage include: Step 1.1: The sewage to be treated passes through the sewage inlet (16) and is regulated by the controller (9). The sewage to be treated enters the fluidized bed reactor (1) from the sewage inlet (17) of the fluidized bed reactor. The controller (9) regulates the hydrogen peroxide silo (10) and the divalent iron silo (11) respectively to add hydrogen peroxide and iron salt into the fluidized bed reactor (1). The divalent iron in the iron salt reacts with the hydrogen peroxide to generate hydroxyl radicals and trivalent iron. The hydroxyl radicals oxidize the difficult-to-degrade pollutants in the sewage to be treated. The trivalent iron crystallizes on the carrier particles from top to bottom. The effluent enters the effluent tank (8) and is discharged through the outlet (2) after being tested and meeting the standards. Step 1.2: The crystallized carrier particles enter the inclined tube (20) of the baffled riser from the solid phase and enter the baffled riser (6). The hydrogen peroxide enters the inclined tube (25) of the baffled riser through the controller (9) and enters the baffled riser (6). The crystals on the carrier particles react with the hydrogen peroxide to generate divalent iron and peroxyhydroxyl radicals. The peroxyhydroxyl radicals continue to react with the crystals on the carrier to generate divalent iron and oxygen. The divalent iron, peroxyhydroxyl radicals and oxygen generated by the reaction are transported to the solid-liquid separator (5). Step 1.3: In the solid-liquid separator (5), the oxygen generated by the reaction and the oxygen generated by the self-decomposition of hydrogen peroxide are recovered. The liquid phase product is separated and returned to the fluidized bed reactor (1) through the recycling water tank control valve (3) and the recycling water tank (4) to participate in the Fenton reaction and wash away the crystals on the solid phase product; Step 1.4: The solid phase product after elution and crystallization is transported to the fluidized bed reactor (1) through the inclined tube (21) of the solid phase fluidized bed reactor for reuse.

4. The method for operating a gas-liquid-solid circulating fluidized bed reactor according to claim 3, characterized in that: The steps of Fenton reaction on tryptophan wastewater include: Step 2.1: The tryptone wastewater to be treated is passed through the wastewater inlet (16) and, under the control of the controller (9), enters the fluidized bed reactor (1) from the wastewater inlet (17) of the fluidized bed reactor. The controller (9) controls the hydrogen peroxide silo (10) and the divalent iron silo (11) respectively to add hydrogen peroxide and iron salt to the fluidized bed reactor (1); Step 2.2: The divalent iron in the iron salt reacts with hydrogen peroxide to generate hydroxyl radicals and trivalent iron. The hydroxyl radicals oxidize the difficult-to-degrade pollutants in the tryptophan wastewater to be treated. The trivalent iron crystallizes on the carrier particles from top to bottom. The crystallized carrier particles enter the inclined tube (20) of the baffled riser through the solid phase and enter the baffled riser (6). Step 2.2 is repeated 3-5 times. Step 2.3: After 3-5 cycles, the to-be-treated tryptophan wastewater is diverted under the control of the controller (9), and the diverted tryptophan wastewater is mixed with the hydrogen peroxide solution and enters the diverted riser (6) through the inclined tube (25) that enters the diverted riser. The crystals on the carrier particles react with the hydrogen peroxide to generate divalent iron and peroxyhydroxyl radicals. The peroxyhydroxyl radicals continue to react with the crystals on the carrier to generate divalent iron and oxygen. The tryptophan substances in the to-be-treated tryptophan wastewater also react with the peroxyhydroxyl radicals. Step 2.3 is repeated until the treated alcohol wastewater meets the discharge standard. Step 2.4: The divalent iron, peroxyhydroxyl radicals and oxygen generated by the reaction are transported to the solid-liquid separator (5) to recover the oxygen generated by the reaction and the oxygen generated by the self-decomposition of hydrogen peroxide. The liquid phase product is separated and returned to the fluidized bed reactor (1) through the recycling water tank control valve (3) and the recycling water tank (4) to participate in the Fenton reaction and wash away the crystals on the solid phase product; Step 2.4: The solid phase product after elution and crystallization is transported to the fluidized bed reactor (1) through the inclined tube (21) of the solid phase fluidized bed reactor for reuse.

5. The method for operating a gas-liquid-solid circulating fluidized bed reactor according to claim 3 or 4, characterized in that: During the operation of the gas-liquid-solid circulating fluidized bed reactor, the pH control device (24) controls the pH value of the fluidized bed reactor (1) to be between 3 and 4.

6. The method for operating a gas-liquid-solid circulating fluidized bed reactor according to claim 3 or 4, characterized in that: The molar ratio of the total molar amount of divalent iron to hydrogen peroxide in the fluidized bed reactor (1) is (1:1)-(1:1.12), and the concentration of hydrogen peroxide is more than 30%.

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