Method and equipment for dephosphorizing and desulfurizing yellow phosphorus tail gas

Abstract

The invention discloses a method and equipment for dephosphorizing and desulfurizing yellow phosphorus tail gas, aiming at solving the technical problem of efficiently removing phosphorus-containing pollutants and sulfur-containing pollutants in the yellow phosphorus tail gas. Comprising the following steps: introducing yellow phosphorus tail gas into a dephosphorization device to remove phosphorus-containing substances in the yellow phosphorus tail gas, wherein the dephosphorization device adopts a first catalytic flue gas treatment device; introducing the dephosphorized flue gas into an organic sulfur hydrolysis conversion device to convert organic sulfur in the dephosphorized flue gas into H2S, wherein the organic sulfur hydrolysis conversion device adopts a second catalytic flue gas treatment device; and introducing the organic sulfur hydrolysis conversion flue gas into a desulfurization device to remove H2S in the organic sulfur hydrolysis conversion flue gas, wherein the desulfurization device adopts a third catalytic flue gas treatment device. The efficient continuous treatment of phosphorus-containing pollutants and sulfur-containing pollutants in the yellow phosphorus tail gas can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of catalytic flue gas treatment, and in particular to a method and equipment for dephosphorization and desulfurization of yellow phosphorus tail gas and a catalytic flue gas treatment device. Background Art

[0002] In order to remove sulfur dioxide from the flue gas to be treated, the applicant has developed a catalytic flue gas treatment technology. For example, the applicant has disclosed catalytic flue gas desulfurization equipment in patent documents with publication numbers CN214764545U, CN114653202A, and CN114797450A. However, their use is limited to the removal of sulfur dioxide.

[0003] On the other hand, yellow phosphorus tail gas is a process gas mainly containing carbon monoxide, which is discharged after the phosphorus collection process in the electric furnace yellow phosphorus production process. In addition to CO, the gas usually also contains impurities such as P4, CO2, PH3, O2, COS, CS2, H2S, water vapor, HF, etc. At present, the main methods for purifying yellow phosphorus tail gas are:

[0004] 1) Water washing method: Introduce yellow phosphorus tail gas into a water washing tower to remove most of the dust and fluoride, phosphide and sulfide;

[0005] 2) Alkali washing method: Introduce the yellow phosphorus tail gas into the alkaline washing tower and wash it with NaOH solution to remove a large amount of acidic gases such as H2S and CO2 in the tail gas;

[0006] 3) Temperature swing adsorption (TSA): Use temperature changes to control the adsorption and desorption process, adsorption at low temperature, desorption and regeneration at high temperature, mainly used for dephosphorization;

[0007] 4) Pressure swing adsorption (PSA): using pressure changes to control the adsorption and desorption process, high pressure adsorption, low pressure desorption regeneration, mainly used to remove H2S and CO2 in yellow phosphorus tail gas;

[0008] 5) DePOx continuous catalytic oxidation dephosphorization process: a continuous treatment process that uses a selective catalyst to oxidize PH3 in yellow phosphorus tail gas into elemental phosphorus and water at 200-300°C and near normal pressure by precisely controlling the amount of oxygen;

[0009] 6) For phosphine and hydrogen sulfide in yellow phosphorus tail gas, there are also ferric chloride method, sodium hypochlorite oxidation method, concentrated sulfuric acid absorption method, and hydrogen peroxide oxidation method. They all use chemical oxidants (FeCl3, NaClO, H2SO4, H2O2) to oxidize PH3 and H2S into harmless or easy-to-handle products, so they can be collectively referred to as chemical oxidant oxidation methods.

[0010] At present, most manufacturers adopt a combination of water washing and alkaline washing processes. A small number of manufacturers, based on the water washing and alkaline washing processes, also add temperature swing adsorption (TSA), pressure swing adsorption (PSA), DePOx continuous catalytic oxidation dephosphorization process, and chemical oxidant oxidation process. Summary of the invention

[0011] The purpose of the present invention is to provide a novel method and equipment for dephosphorization and desulfurization of yellow phosphorus tail gas, so as to solve the technical problem of efficiently removing phosphorus-containing pollutants and sulfur-containing pollutants in yellow phosphorus tail gas.

[0012] In addition, another object of the present invention is to provide a catalytic flue gas treatment device, which can be used in but not limited to the above-mentioned yellow phosphorus tail gas dephosphorization and desulfurization method and equipment to solve the technical problem of secondary pollution caused by the generation of sulfur dioxide when catalytic oxidation of H2S.

[0013] In the first aspect, a method for dephosphorization and desulfurization of yellow phosphorus tail gas is provided, comprising: passing the yellow phosphorus tail gas into a dephosphorization device to remove phosphorus-containing substances in the yellow phosphorus tail gas, the dephosphorization device adopts a first catalytic flue gas treatment device, the first catalytic flue gas treatment device comprises a first reactor, when working, the yellow phosphorus tail gas enters the first reactor from the air inlet of the first reactor, passes through a first catalyst, and is then discharged from the exhaust port of the first reactor to become dephosphorized flue gas, PH3 and P4 in the yellow phosphorus tail gas react on the first catalyst to form phosphorus oxides and phosphoric acid when passing through the first catalyst, when the first catalyst is washed and regenerated, the phosphorus oxides and the phosphoric acid enter the regeneration liquid sprayed on the first catalyst and are then discharged from the discharge port of the first reactor; the dephosphorized flue gas is passed into an organic sulfur hydrolysis conversion device to convert the organic sulfur in the dephosphorized flue gas into H2S, the organic sulfur hydrolysis conversion device adopts a second catalytic flue gas treatment device, the second catalytic flue gas treatment device comprises a second reactor, when working, the dephosphorized flue gas is passed from the air inlet of the second reactor The organic sulfur hydrolysis-converted flue gas enters the second reactor and then passes through the second catalyst and is then discharged from the exhaust port of the second reactor to become organic sulfur hydrolysis-converted flue gas. The organic sulfur in the dephosphorized flue gas is hydrolyzed and converted into H2S when passing through the second catalyst. The organic sulfur hydrolysis-converted flue gas is passed into a desulfurization device to remove H2S in the organic sulfur hydrolysis-converted flue gas. The desulfurization device adopts a third catalytic flue gas treatment device. The third catalytic flue gas treatment device includes a third reactor. When working, the organic sulfur hydrolysis-converted flue gas enters the third reactor from the air inlet of the third reactor and then passes through the third catalyst and is then discharged from the exhaust port of the third reactor to become desulfurized flue gas. The H2S in the organic sulfur hydrolysis-converted flue gas reacts on the third catalyst to form elemental S and sulfuric acid when passing through the third catalyst. The sulfuric acid is generated by further catalytic oxidation of sulfur dioxide generated by the reaction of the elemental S with oxygen and reacting with water. When the third catalyst is washed and regenerated, the elemental S and the sulfuric acid enter the regeneration liquid sprayed on the third catalyst and are then discharged from the drain port of the third reactor.

[0014] In the second aspect, a yellow phosphorus tail gas dephosphorization and desulfurization device comprises: a dephosphorization device for receiving yellow phosphorus tail gas and removing phosphorus-containing substances in the yellow phosphorus tail gas, the dephosphorization device adopts a first catalytic flue gas treatment device, the first catalytic flue gas treatment device comprises a first reactor, when working, the yellow phosphorus tail gas enters the first reactor from the air inlet of the first reactor, passes through the first catalyst, and is then discharged from the exhaust port of the first reactor to become dephosphorized flue gas, PH3 and P4 in the yellow phosphorus tail gas react on the first catalyst to form phosphorus oxides and phosphoric acid when passing through the first catalyst, when the first catalyst is washed and regenerated, the phosphorus oxides and the phosphoric acid enter the regeneration liquid sprayed on the first catalyst and are discharged from the discharge port of the first reactor; an organic sulfur hydrolysis conversion device for receiving the dephosphorized flue gas and converting the organic sulfur in the dephosphorized flue gas into H2S, the organic sulfur hydrolysis conversion device adopts a second catalytic flue gas treatment device, the second catalytic flue gas treatment device comprises a second reactor, when working, the dephosphorized flue gas enters the air inlet of the second reactor The second reactor then passes through the second catalyst and is then discharged from the exhaust port of the second reactor to become organic sulfur hydrolysis conversion flue gas. The organic sulfur in the dephosphorized flue gas is hydrolyzed and converted into H2S when passing through the second catalyst. A desulfurization device is used to receive the organic sulfur hydrolysis conversion flue gas and remove H2S from the organic sulfur hydrolysis conversion flue gas. The desulfurization device adopts a third catalytic flue gas treatment device. The third catalytic flue gas treatment device includes a third reactor. When working, the organic sulfur hydrolysis conversion flue gas enters the third reactor from the air inlet of the third reactor and then passes through the third catalyst and is then discharged from the exhaust port of the third reactor to become desulfurized flue gas. The H2S in the organic sulfur hydrolysis conversion flue gas reacts on the third catalyst to form elemental S and sulfuric acid when passing through the third catalyst. The sulfuric acid is generated by further catalytic oxidation of sulfur dioxide generated by the reaction of the elemental S with oxygen and reacting with water. When the third catalyst is washed and regenerated, the elemental S and the sulfuric acid enter the regeneration liquid sprayed on the third catalyst and are discharged from the drain port of the third reactor.

[0015] The above-mentioned yellow phosphorus tail gas dephosphorization and desulfurization method and equipment adopts a three-stage catalytic flue gas treatment: the first stage converts PH3 and P4 into controllable phosphorus oxides and phosphoric acid through catalytic oxidation; the second stage converts organic sulfur (such as COS, CS2) into H2S through catalytic hydrolysis; the third stage catalytically oxidizes H2S to elemental S. The entire treatment process can achieve efficient and continuous treatment of phosphorus-containing pollutants and sulfur-containing pollutants in yellow phosphorus tail gas through the selective reaction of the catalyst. In addition, in order to solve the problem that elemental S is easily oxidized to form sulfur dioxide and cause secondary pollution, the third catalyst can further catalytically oxidize sulfur dioxide and react with water to form sulfuric acid, thereby avoiding the emission of sulfur dioxide.

[0016] More specifically, the above three-stage catalytic flue gas treatment has the following coupling effects: First, phosphides (especially PH3 and P4) are toxic in themselves and will poison the subsequent catalysts (phosphides such as PH3 and P4 have strong reducing and coordination properties. When they come into contact with the catalyst surface, they are prone to certain chemical adsorption and chemical reactions with the catalyst active sites, thereby occupying or covering the catalyst active sites). Therefore, by preferentially removing phosphides, the activity and service life of the subsequent second and third catalysts can be effectively protected. Secondly, organic sulfur is uniformly converted into H2S through the second-stage catalytic hydrolysis. Compared with organic sulfides such as COS and CS2, H2S is more easily catalytically oxidized, which can significantly improve the desulfurization efficiency of the third stage. Finally, the temperature gradient and chemical reaction characteristics of the entire treatment chain form a good synergistic effect.

[0017] According to a third aspect, a catalytic flue gas treatment device is provided, comprising: a reaction system for removing H2S in the flue gas to be treated by reaction, comprising at least one reactor, wherein the reactor has an air inlet, an exhaust port, a liquid discharge port and a catalyst located in the reactor, wherein the reactor is provided with a regeneration liquid spraying device for washing and regenerating the catalyst, wherein during operation, the flue gas to be treated enters the reactor from the air inlet of the reactor, passes through the catalyst and is then discharged from the exhaust port of the reactor to become treated flue gas, wherein the H2S in the flue gas to be treated reacts on the catalyst to form elemental S and sulfuric acid when passing through the catalyst, wherein the sulfuric acid is generated by further catalytic oxidation of sulfur dioxide generated by the reaction of the elemental S with oxygen and reacting with water, and wherein when the catalyst is washed and regenerated, the elemental S and the sulfuric acid enter the regeneration liquid sprayed on the catalyst and are then discharged from the liquid discharge port of the reactor; A liquid circulation system, comprising at least one regeneration liquid tank and a regeneration liquid circulation control pipeline network connected between the at least one regeneration liquid tank and each reactor, wherein the regeneration liquid circulation control pipeline network comprises an output side control pipeline network, an input side control pipeline network and a regeneration liquid driving device, wherein the output side control pipeline network can introduce the regeneration liquid in the selected regeneration liquid tank into the regeneration liquid spraying device of the selected reactor, and the input side control pipeline network can introduce the regeneration liquid output from the discharge port of the selected reactor into the selected regeneration liquid tank, and the regeneration liquid driving device can provide the required power to the regeneration liquid; a flue gas conveying system, comprising an air intake pipeline network and an exhaust pipeline network, wherein the air intake pipeline network comprises an air intake main pipe and various air intake branches connecting the air intake main pipe to the air intake ports of each reactor respectively, and each air intake branch pipe has an on-off control mechanism respectively, and the exhaust pipeline network comprises an exhaust main pipe and various exhaust branches connecting the exhaust main pipe to the exhaust ports of each reactor respectively.

[0018] The above-mentioned catalytic flue gas treatment device integrates a reaction system, a regeneration liquid circulation system and a flue gas delivery system. The catalyst converts H2S into elemental S. In view of the problem that elemental S is easily oxidized to form sulfur dioxide, thereby causing secondary pollution, the catalyst can further catalytically oxidize sulfur dioxide and react with water to form sulfuric acid, thereby avoiding the problem of sulfur dioxide emissions. In addition, the regeneration liquid circulation system realizes directional transportation and recovery of the regeneration liquid through a circulation control network, and the operation is flexible; the design of the intake and exhaust pipe network of the flue gas delivery system enables multiple reactors to operate in parallel, which is convenient for maintenance and overhaul. It can be used in, but not limited to, the above-mentioned yellow phosphorus tail gas dephosphorization and desulfurization method and equipment.

[0019] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. Additional aspects and advantages provided by the present invention will be partially given in the following description, partially become apparent from the following description, or be learned through practice. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting a part of this specification are used to assist in understanding the present invention. The contents provided in the drawings and their related descriptions in this specification may be used to explain the present invention, but shall not constitute improper limitations on the present invention.

[0021] Figure 1 This is a schematic diagram of a yellow phosphorus tail gas dephosphorization and desulfurization device according to an embodiment of the present invention.

[0022] Figure 2 for Figure 1 A partial enlarged view of the desulfurization unit.

[0023] Figure 3 for Figure 1 Schematic diagram of the specific structure of the desulfurization device.

[0024] Figure 4 It is a schematic diagram of a pre-desulfurization device in a yellow phosphorus tail gas dephosphorization and desulfurization equipment according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The present invention is described clearly and completely below in conjunction with the accompanying drawings. A person skilled in the art will be able to implement the present invention based on these descriptions. Before describing the present invention in conjunction with the accompanying drawings, it should be particularly noted that:

[0026] The technical solutions and technical features provided in each section, including the following description, can be combined with each other without conflict. In addition, where possible, these technical solutions, technical features and related combinations can be assigned specific technical themes and protected by relevant patents.

[0027] The embodiments of the present invention involved in the following description are generally only a part of the embodiments rather than all the embodiments. Based on these embodiments, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of patent protection.

[0028] The terms "include", "comprises", "have" and any variations thereof in this specification and the corresponding claims and related parts are intended to cover non-exclusive inclusions. Other related terms and units can be reasonably interpreted based on the relevant content provided in this specification.

[0029] Figure 1 This is a schematic diagram of a yellow phosphorus tail gas dephosphorization and desulfurization device according to an embodiment of the present invention. Figure 1 As shown, a yellow phosphorus tail gas dephosphorization and desulfurization device mainly includes: a dephosphorization device 7, an organic sulfur hydrolysis conversion device 8 and a desulfurization device 9.

[0030] The dephosphorization device 7 is used to receive yellow phosphorus tail gas and remove phosphorus-containing substances in the yellow phosphorus tail gas. The dephosphorization device 7 adopts a first catalytic flue gas treatment device, which includes a first reactor 71. During operation, the yellow phosphorus tail gas enters the first reactor 71 from the air inlet of the first reactor 71, passes through the first catalyst, and is then discharged from the exhaust port of the first reactor 71 to become dephosphorized flue gas. PH3 and P4 in the yellow phosphorus tail gas react on the first catalyst to form phosphorus oxides and phosphoric acid when passing through the first catalyst. When the first catalyst is washed and regenerated, the phosphorus oxides and the phosphoric acid enter the regeneration liquid sprayed on the first catalyst and are discharged from the discharge port of the first reactor 71.

[0031] The organic sulfur hydrolysis conversion device 8 is used to receive the dephosphorized flue gas and convert the organic sulfur in the dephosphorized flue gas into H2S. The organic sulfur hydrolysis conversion device 8 adopts a second catalytic flue gas treatment device, and the second catalytic flue gas treatment device includes a second reactor 81. During operation, the dephosphorized flue gas enters the second reactor 81 from the air inlet of the second reactor 81, passes through the second catalyst, and is discharged from the exhaust port of the second reactor 81 to become organic sulfur hydrolysis conversion flue gas. The organic sulfur in the dephosphorized flue gas is hydrolyzed and converted into H2S when passing through the second catalyst.

[0032] The desulfurization device 9 is used to receive the organic sulfur hydrolysis conversion flue gas and remove H2S in the organic sulfur hydrolysis conversion flue gas. The desulfurization device 9 adopts a third catalytic flue gas treatment device, and the third catalytic flue gas treatment device includes a third reactor 91. During operation, the organic sulfur hydrolysis conversion flue gas enters the third reactor 91 from the air inlet of the third reactor 91, passes through the third catalyst, and is then discharged from the exhaust port of the third reactor 91 to become desulfurized flue gas. The H2S in the organic sulfur hydrolysis conversion flue gas reacts on the third catalyst to form elemental S and sulfuric acid when passing through the third catalyst. The sulfuric acid is generated by further catalytic oxidation of sulfur dioxide generated by the reaction of the elemental S with oxygen and reacting with water. When the third catalyst is washed and regenerated, the elemental S and the sulfuric acid enter the regeneration liquid sprayed on the third catalyst and are discharged from the discharge port of the third reactor 91.

[0033] The above-mentioned yellow phosphorus tail gas dephosphorization and desulfurization equipment adopts a three-stage catalytic flue gas treatment method: the first stage converts PH3 and P4 into controllable phosphorus oxides and phosphoric acid through catalytic oxidation; the second stage converts organic sulfur (such as COS, CS2) into H2S through catalytic hydrolysis; the third stage catalytically oxidizes H2S to elemental S. The entire treatment process can achieve efficient and continuous treatment of phosphorus-containing pollutants and sulfur-containing pollutants in yellow phosphorus tail gas through the selective reaction of the catalyst. In addition, in order to solve the problem that elemental S is easily oxidized to form sulfur dioxide and cause secondary pollution, the third catalyst can further catalytically oxidize sulfur dioxide and react with water to form sulfuric acid, thereby avoiding the emission of sulfur dioxide.

[0034] More specifically, the above three-stage catalytic flue gas treatment has the following coupling effects: First, phosphides (especially PH3 and P4) are toxic in themselves and will poison the subsequent catalysts (phosphides such as PH3 and P4 have strong reducing and coordination properties. When they come into contact with the catalyst surface, they are prone to certain chemical adsorption and chemical reactions with the catalyst active sites, thereby occupying or covering the catalyst active sites). Therefore, by preferentially removing phosphides, the activity and service life of the subsequent second and third catalysts can be effectively protected. Secondly, organic sulfur is uniformly converted into H2S through the second-stage catalytic hydrolysis. Compared with organic sulfides such as COS and CS2, H2S is more easily catalytically oxidized, which can significantly improve the desulfurization efficiency of the third stage. Finally, the temperature gradient and chemical reaction characteristics of the entire treatment chain form a good synergistic effect.

[0035] like Figure 1As shown, the above-mentioned yellow phosphorus tail gas dephosphorization and desulfurization equipment may also include a leaching pretreatment device, which is arranged before the dephosphorization device 7, and is used to perform leaching pretreatment on the yellow phosphorus tail gas before sending it into the dephosphorization device 7; the leaching pretreatment 7 includes a first leaching system 1 and / or a second leaching system 2, the first leaching system 1 is used to perform water leaching treatment on the yellow phosphorus tail gas, and the second leaching system 2 is used to perform alkaline solution leaching treatment on the yellow phosphorus tail gas.

[0036] Specifically, in this embodiment, the elution pretreatment 7 includes a first elution system 1 and a second elution system 2, wherein the first elution system 1 includes two-stage first elution towers, and the second elution system 2 includes one-stage second elution tower, and the second elution tower is arranged in series after the two-stage first elution towers.

[0037] The elution pretreatment device is mainly used to remove large particulate matter and some water-soluble gaseous pollutants in yellow phosphorus tail gas. Water elution treatment can preliminarily remove some phosphorus- and sulfur-containing compounds, and alkaline solution elution treatment can further remove acidic gases, thereby reducing the load of subsequent treatment.

[0038] In addition, a gas-liquid separation device 3 and a gas heating device are sequentially arranged between the leaching pretreatment device and the dephosphorization device 7. The function of the gas-liquid separation device 3 is to achieve gas-liquid separation, and the separated yellow phosphorus tail gas can first enter the gas separation cylinder 4, and the gas separation cylinder 4 can shunt the yellow phosphorus tail gas as needed. For example, the gas separation cylinder 4 can shunt a part of the yellow phosphorus tail gas to a gas tank for storage (the yellow phosphorus tail gas in the gas tank can be used for combustion) and shunt a part of the yellow phosphorus tail gas to the gas heating device.

[0039] The gas separation cylinder 4 is arranged after the gas-liquid separation device 3 and before the gas heating device, and can divert the yellow phosphorus tail gas according to actual needs, which not only realizes the rational use of resources, but also avoids overloading of subsequent catalytic treatment devices.

[0040] In this embodiment, the gas heating device specifically includes a heat exchanger 5 and a heater 6. The function of the heat exchanger 5 is to use the yellow phosphorus tail gas output by the desulfurization device 9 to preheat the yellow phosphorus tail gas output by the gas cylinder 4, and the function of the heater 6 is to use external water vapor to further heat the yellow phosphorus tail gas preheated by the heat exchanger 5.

[0041] The gas heating device adopts a two-stage heating method of a heat exchanger 5 and a heater 6. This design not only saves energy but also ensures that the yellow phosphorus gas entering the dephosphorization device 7 reaches a suitable reaction temperature.

[0042] In summary, the working process of the above-mentioned yellow phosphorus tail gas dephosphorization and desulfurization equipment is as follows: the yellow phosphorus tail gas first passes through the first elution system (including two-stage first elution towers) for water elution treatment and the second elution system (including one-stage second elution tower) for alkaline solution elution treatment, and then enters the gas separation cylinder 4 after separation by the gas-liquid separation device 3. The gas separation cylinder 4 diverts part of the yellow phosphorus tail gas to the gas tank for storage for combustion, and the other part is heated by the heat exchanger 5 (preheating the yellow phosphorus tail gas output by the desulfurization device 9) and the heater 6, and then enters the dephosphorization device 7 (PH3 and P4 react on the first catalyst to form phosphorus oxides and phosphoric acid), the organic sulfur hydrolysis conversion device 8 (organic sulfur is hydrolyzed on the second catalyst to form H2S) and the desulfurization device 9 (H2S reacts on the third catalyst to form elemental S and sulfuric acid), and is finally discharged as desulfurized flue gas.

[0043] It should be pointed out that the above-mentioned first catalytic flue gas treatment device, the second catalytic flue gas treatment device and the third catalytic flue gas treatment device all use catalytic method to treat flue gas. From the process principle point of view, each of them is not a brand new technology (for example, there is a technology for catalytic hydrolysis of organic sulfur into hydrogen sulfide in the field of natural gas purification), but the key lies in the combination method and the selection of suitable catalysts and operating process parameters according to the combined process.

[0044] In this embodiment, the operating conditions of the first reactor are:

[0045] 1) First catalyst formula:

[0046] The first catalyst is mainly composed of the following components in parts by weight uniformly mixed:

[0047] Nano PdO particles: 0.8-1.2 parts;

[0048] Nano PtO2 particles: 0.4-0.6 parts;

[0049] CeO2: 3.5-4.5 parts;

[0050] V2O5: 2.5-3.5 parts;

[0051] Activated carbon carrier: 90-93 parts;

[0052] Wherein, the weight ratio of nano-PdO particles to nano-PtO2 particles is (1.8-2):1, and the weight ratio of CeO2 to V2O5 is (1.2-1.5):1;

[0053] 2) Operation parameters of the first reactor: operate at 100-120℃, control the air velocity to 1000-2000h -1 , O2 concentration in the gas phase is 5-8% (v / v%), and the moisture content is less than 2% (v / v%).

[0054] It can be seen that the first catalyst is mainly composed of nano-PdO particles, nano-PtO2 particles, CeO2, V2O5 and activated carbon carrier, wherein the weight ratio of nano-PdO to nano-PtO2 is controlled at (1.8-2):1, and the weight ratio of CeO2 to V2O5 is controlled at (1.2-1.5):1. Under the conditions of 100-120℃ and the space velocity of 1000-2000h -1 , it operates under the conditions of O2 concentration of 5-8% (v / v%) in the gas phase and moisture content less than 2% (v / v%).

[0055] Nano-scale PdO and PtO2 in the first catalyst are the main active components, which have excellent oxidation catalytic performance and can efficiently catalyze the oxidation conversion of PH3 and P4; CeO2 has good oxygen storage and release performance and redox performance, which can provide active oxygen for the reaction; V2O5 can improve the sulfur resistance of the catalyst; and the activated carbon carrier provides a large specific surface area, which is conducive to the dispersion of active components and the adsorption of reactants. The overall formula design achieves efficient catalytic oxidation of phosphorus-containing pollutants.

[0056] Specifically, CeO2 has a unique fluorite crystal structure, Ce ions can reversibly switch between +3 and +4 valence states, and lattice oxygen can freely enter and exit the lattice to form oxygen vacancies. Under oxygen-rich conditions, CeO2 can absorb and store oxygen. 3+ Oxidized to Ce 4+ ; Under hypoxic conditions, Ce 4+ It will release oxygen and reduce to Ce 3+ This oxygen storage and release process can be expressed as: This property enables CeO2 to regulate the local oxygen concentration and continuously provide active oxygen for the catalytic oxidation reaction, thereby maintaining stable catalytic activity. The oxygen vacancies on the CeO2 surface can serve as active sites, promoting the activation of oxygen molecules and improving the catalytic oxidation efficiency.

[0057] V2O5 forms a VOV structure in the catalyst, which has a strong resistance to sulfur poisoning. When sulfur-containing compounds come into contact with the catalyst, the sulfate formed on the surface of V2O5 is easier to decompose and will not accumulate on the catalyst surface to form stable sulfides, thus avoiding permanent deactivation of active sites. In addition, there is a strong interaction between V2O5 and CeO2, forming a Ce-OV bridge bond structure, which further enhances the redox performance and sulfur resistance of the catalyst. During the catalyst regeneration process, V2O5 also helps to oxidize and remove sulfides, allowing the catalyst to continue to maintain high activity.

[0058] The reaction formulas involved in the first reactor are: 4PH3+8O2→2P2O5+6H2O; P4+5O2→P2O5;

[0059] P2O5+3H2O→2H3PO4.

[0060] In this embodiment, the operating conditions of the second reactor are:

[0061] 1) Second catalyst formula:

[0062] The second catalyst is mainly composed of the following components in parts by weight uniformly mixed:

[0063] CeO2: 5-7 parts;

[0064] V2O5: 3-4 parts;

[0065] MoO3: 2-3 parts;

[0066] γ-Al2O3 carrier: 86-90 parts;

[0067] Among them, the weight ratio of CeO2 to V2O5 is (1.6-1.8):1, and the weight ratio of V2O5 to MoO3 is (1.4-1.6):1;

[0068] 2) Operation parameters of the second reactor: operate at 70-90°C and control the air velocity to 1000-2000h -1 , the moisture content is 15-20% (v / v%).

[0069] It can be seen that the second catalyst is mainly composed of CeO2, V2O5, MoO3 and γ-Al2O3 carrier, wherein the weight ratio of CeO2 to V2O5 is (1.6-1.8):1, and the weight ratio of V2O5 to MoO3 is (1.4-1.6):1. Under the condition of 70-90℃ and the space velocity of 1000-2000h -1 , and operate under the condition of moisture content 15-20% (v / v%).

[0070] CeO2 through Ce 4+ / Ce 3+ The valence state conversion provides sufficient redox active sites and forms a stable Ce-OV structure with V2O5 to enhance the anti-poisoning ability; V2O5 provides an appropriate amount of acidic sites to promote the hydrolysis reaction, and its V-OH group can activate water molecules to accelerate the hydrolysis process; MoO3 not only 6+ It provides additional Lewis acid sites to enhance hydrolysis activity, effectively inhibits sulfur poisoning and forms a Mo-O-Ce structure with other components; the γ-Al2O3 carrier has a large specific surface area (>200m 2 / g) and suitable pore structure ensure that the active components are highly dispersed while providing excellent mechanical strength and thermal stability. The precise ratio of the three active components (CeO2:V2O5=(1.6-1.8):1, V2O5:MoO3=(1.4-1.6):1) ensures the optimal balance between acidic sites and redox sites, achieving efficient and stable hydrolysis conversion of organic sulfur under low temperature conditions.

[0071] The hydrolysis conversion process includes the following reaction formulas: COS+H2O=H2S+CO2 and CS2+2H2O=2H2S+CO2.

[0072] In this embodiment, the operating conditions of the third reactor are:

[0073] 1) The third catalyst formula:

[0074] The third catalyst is mainly composed of the following components in parts by weight uniformly mixed:

[0075] Fe2O3: 3-5 parts;

[0076] CuO: 2-3 parts;

[0077] MnO2: 1-2 parts;

[0078] Activated carbon carrier: 90-94 parts;

[0079] Wherein, the weight ratio of Fe2O3 to CuO is (1.5-1.8):1, and the weight ratio of CuO to MnO2 is (1.8-2.0):1;

[0080] 2) Operation parameters of the third reactor:

[0081] Run at 65-85℃, control airspeed at 800-1500h -1 , the O2 concentration in the gas phase is 3-5% (v / v%), and the moisture content is 2-8% (v / v%).

[0082] The third catalyst is mainly composed of Fe2O3, CuO, MnO2 and activated carbon carrier, wherein the weight ratio of Fe2O3 to CuO is (1.5-1.8):1, and the weight ratio of CuO to MnO2 is (1.8-2.0):1. Under the condition of 65-85℃, the space velocity is 800-1500h -1 , it operates under the conditions of 3-5% (v / v%) O2 concentration in the gas phase and 2-8% (v / v%) moisture content.

[0083] The third catalyst is actually divided into a first component and a second component. The first component includes Fe2O3, CuO, and MnO2, and is used to catalyze the reaction of H2S and oxygen in the flue gas to be treated to generate elemental S. The second component includes an activated carbon carrier, and is used to further catalytically oxidize the sulfur dioxide generated by the reaction of the elemental S and oxygen and react with water to generate sulfuric acid.

[0084] Fe2O3 is the main active component. 3+ / Fe 2+ Valence state cycle catalyzes H2S oxidation; CuO via Cu 2+ / Cu + The conversion enhances the efficiency of electron transfer; MnO2 provides additional redox sites. The precise ratio of the three oxides (Fe2O3:CuO=(1.5-1.8):1, CuO:MnO2=(1.8-2.0):1) forms an efficient multi-metal oxide composite system, which realizes the selective oxidation of H2S to elemental sulfur at low temperature (65-85℃). The appropriate oxygen concentration and water content during the reaction are conducive to maintaining the catalytic cycle and inhibiting over-oxidation.

[0085] Activated carbon not only provides a large specific surface area to disperse active components as a carrier, but more importantly, its surface oxygen-containing functional groups play a key role in the second-stage reaction. When a small amount of elemental sulfur is over-oxidized to generate SO2, the oxygen-containing functional groups on the surface of activated carbon can catalyze the further oxidation of SO2 and convert it into sulfuric acid in the presence of water, thereby achieving deep desulfurization. This dual-functional catalytic system not only ensures the efficient removal of H2S under low temperature conditions, but also can process the SO2 generated during the process, reflecting the integrity and advancement of the catalyst design.

[0086] It can be seen that the three-stage catalytic flue gas treatment implemented by the above-mentioned yellow phosphorus tail gas dephosphorization and desulfurization equipment belongs to low-temperature catalytic technology (the first reactor is operated at 100-120°C, the second reactor is operated at 70-90°C, and the third reactor is operated at 65-85°C), and the temperature of the three-stage catalytic flue gas treatment is reduced step by step. This temperature gradient design reduces energy consumption (heater 6 can use a steam heater, and the steam source required by the steam heater is already available in the yellow phosphorus manufacturer and can be used directly; and the yellow phosphorus tail gas does not need to be heated except for heater 6), while avoiding the catalyst sintering deactivation caused by excessive temperature.

[0087] Figure 2 for Figure 1 A partial enlarged view of the desulfurization unit. Figure 3 for Figure 1 Schematic diagram of the specific structure of the desulfurization device. Figure 2-Figure 3 As shown, the above desulfurization device specifically includes: a reaction system, a regeneration liquid circulation system and a flue gas transportation system. Figure 1 It can be seen that the above-mentioned dephosphorization device also includes a reaction system, a regeneration liquid circulation system and a flue gas conveying system. The following will focus on the reaction system, the regeneration liquid circulation system and the flue gas conveying system of the desulfurization device.

[0088] like Figure 2-Figure 3 As shown, the reaction system of the desulfurization device is used for reacting and removing H2S in the flue gas to be treated, and comprises at least one reactor (i.e., the third reactor 91), wherein the reactor has an air inlet, an exhaust port, a liquid discharge port and a catalyst (i.e., the third catalyst) located in the reactor, and the reactor is provided with a regeneration liquid spraying device for washing and regenerating the catalyst. During operation, the flue gas to be treated enters the reactor from the air inlet of the reactor, passes through the catalyst, and is then discharged from the exhaust port of the reactor to become treated flue gas. When passing through the catalyst, the H2S in the flue gas to be treated reacts on the catalyst to form elemental S and sulfuric acid. The sulfuric acid is generated by further catalytic oxidation of sulfur dioxide generated by the reaction of the elemental S with oxygen and reacting with water. When the catalyst is washed and regenerated, the elemental S and the sulfuric acid enter the regeneration liquid sprayed on the catalyst and are then discharged from the liquid discharge port of the reactor.

[0089] The regeneration liquid circulation system 92 includes at least one regeneration liquid tank 921 and a regeneration liquid circulation control pipeline network connected between the at least one regeneration liquid tank 921 and each reactor. The regeneration liquid circulation control pipeline network has an output side control pipeline network 922, an input side control pipeline network 923 and a regeneration liquid driving device. The output side control pipeline network 922 can introduce the regeneration liquid in the selected regeneration liquid tank 921 into the regeneration liquid spraying device of the selected reactor, and the input side control pipeline network 923 can introduce the regeneration liquid output from the discharge port of the selected reactor into the selected regeneration liquid tank 921. The regeneration liquid driving device can provide the required power to the regeneration liquid.

[0090] The flue gas delivery system 93 includes an air intake network 931 and an exhaust network 932. The air intake network 931 includes an air intake main pipe and air intake branches respectively connecting the air intake main pipe to the air inlets of each reactor, and each air intake branch has an on-off control mechanism. The exhaust network 932 includes an exhaust main pipe and exhaust branches respectively connecting the exhaust main pipe to the exhaust ports of each reactor.

[0091] Among them, each air intake branch pipe has a bending portion 933 that extends downward, then turns back and extends upward. When it is necessary to cut off the air intake of the smoke in the selected air intake branch pipe, a liquid sealing liquid is injected into the corresponding bending portion 933 through a liquid inlet structure arranged on the corresponding bending portion to form a liquid seal for the bending portion. When it is necessary to conduct the air intake of the smoke in the selected air intake branch pipe, the liquid sealing liquid in the corresponding bending portion is discharged through a liquid discharge structure arranged on the corresponding bending portion 933.

[0092] The above structure of the desulfurization device can refer to the relevant structures of the catalytic flue gas desulfurization equipment involved in the patent documents with publication numbers CN214764545U, CN114653202A, CN114797450A, etc. The working process of the desulfurization device in the present invention and the catalytic flue gas desulfurization equipment in these patent documents is similar.

[0093] However, in the desulfurization device of the present invention, the height of the intake side of the bend 933 on each intake branch pipe is set higher than the height of the exhaust side of the bend 933 (see Figure 2 , the height difference between the height of the air inlet side of the curved portion 933 and the height of the exhaust side of the curved portion 933 is H). In addition, the liquid level of the sealing liquid injected into the curved portion 933 can rise to the exhaust side of the curved portion 933 and overflow from the channel on the exhaust side of the curved portion 933 to the air inlet of the corresponding reactor.

[0094] The height of the air inlet side of the bend 933 on each air inlet branch pipe is set higher than the height of the air outlet side of the bend 933, so that it is easier to control the liquid level of the liquid sealing liquid injected into the bend 933 (the overflow point height of the channel on the air outlet side of the bend 933), and ensure that the overflow direction is always toward the air inlet of the reactor, so as to prevent the liquid sealing liquid from flowing back into the air inlet main pipe. This design makes the flow direction of the liquid sealing liquid more controllable and improves the reliability and safety of the liquid seal.

[0095] In addition, the liquid inlet structure of the bend 933 on each inlet branch pipe is connected to the at least one regeneration liquid tank through a liquid sealing liquid delivery pipeline system. The output side control pipe network 922 includes an output side main pipe and an output side branch connected between the output side main pipe and the regeneration liquid spraying device of each reactor, and each output side branch is provided with a regeneration liquid delivery control valve 924. A liquid sealing liquid delivery manifold 925 is branched out from the pipeline located before the corresponding regeneration liquid delivery control valve 924 on each output side branch, and each liquid delivery manifold is connected to the liquid inlet structure of the bend 933 on the inlet branch pipe of the corresponding reactor through the liquid sealing liquid delivery control valve 925 provided on the liquid delivery manifold in a one-to-one correspondence. The liquid inlet structure is a liquid inlet interface provided on the pipeline on the exhaust side of the corresponding bend 933.

[0096] In this way, when the catalyst in the selected reactor needs to be washed and regenerated, the regeneration liquid in the selected regeneration liquid tank is guided to the regeneration liquid spraying device of the selected reactor through the regeneration liquid circulation system. In this process, the liquid sealing liquid delivery control valve corresponding to the selected reactor is first opened for a period of time, so that the liquid level of the liquid sealing liquid injected into the corresponding bend rises to the overflow height on the exhaust side of the bend, and the liquid sealing liquid is discharged from the channel on the exhaust side of the bend to the air inlet of the corresponding reactor, so that the liquid level of the liquid sealing liquid injected into the corresponding bend is maintained below the overflow height on the exhaust side of the bend, and then the liquid sealing liquid delivery control valve corresponding to the selected reactor is closed and the regeneration liquid delivery control valve corresponding to the selected reactor is ensured to be opened.

[0097] By opening the sealing liquid delivery control valve corresponding to the selected reactor for a period of time, the liquid level of the sealing liquid injected into the corresponding bend rises to the overflow height on the exhaust side of the bend and the sealing liquid is discharged from the channel on the exhaust side of the bend to the air inlet of the corresponding reactor, so that the liquid level of the sealing liquid injected into the corresponding bend is maintained below the overflow height on the exhaust side of the bend, and then the sealing liquid delivery control valve corresponding to the selected reactor is closed and the regeneration liquid delivery control valve corresponding to the selected reactor is opened, not only can the liquid level of the sealing liquid be accurately controlled to prevent the sealing liquid from flowing back into the intake manifold, thereby ensuring the reliability and safety of the liquid seal, but also the sealing liquid and the regeneration liquid are driven simultaneously by the regeneration liquid driving device.

[0098] As mentioned above, the working process of the yellow phosphorus tail gas dephosphorization and desulfurization equipment of the above embodiment is as follows: the yellow phosphorus tail gas is firstly subjected to water elution treatment by the first elution system and alkaline solution elution treatment by the second elution system, and then enters the gas cylinder 4 after separation by the gas-liquid separation device 3. The gas cylinder 4 diverts part of the yellow phosphorus tail gas to the gas cabinet for storage for combustion, and the other part is heated by the heat exchanger 5 and the heater 6, and then enters the dephosphorization device 7, the organic sulfur hydrolysis conversion device 8 and the desulfurization device 9 in sequence, and finally discharged as desulfurized flue gas. The experiment found that after the yellow phosphorus tail gas is washed with water and alkali, it still contains more inorganic sulfur (H2S) and organic sulfur (COS, CS2, etc.). The composition and content of these sulfides depend on the nature and quality of the raw materials, and H2S will react with oxygen to generate sulfur element, which is a yellow solid and will be deposited on the surface of the first catalyst, increasing the resistance of the first catalyst layer.

[0099] Therefore, the yellow phosphorus tail gas dephosphorization and desulfurization equipment according to another embodiment of the present invention improves the above yellow phosphorus tail gas dephosphorization and desulfurization equipment by adding a pre-desulfurization device before the dephosphorization device 7.

[0100] Figure 4 Schematic diagram of a pre-desulfurization device in a yellow phosphorus tail gas dephosphorization and desulfurization device according to an embodiment of the present invention. Figure 4As shown, the pre-desulfurization device 10 adopts a liquid phase absorption process, and its core principle is to use a proprietary liquid phase desulfurization agent in the desulfurization tower 101 to absorb H2S into a rich liquid; the rich liquid (stored in the rich liquid tank 102) is regenerated by contact with air in the ejector 103, and after being restored to a lean liquid, it is returned to the desulfurization tower 101 for use through the lean liquid tank 104.

[0101] This liquid phase desulfurizer can use a mixed solution of sodium carbonate and sodium arsenite, which reacts with H2S during the absorption process to generate NaHS and NaHCO3, and then undergoes an oxidation regeneration reaction when in contact with air in the ejector, while precipitating elemental sulfur; the NaOH generated during the regeneration process reacts with CO2 in the air to regenerate Na2CO3, thereby realizing the recycling of the liquid phase desulfurizer. The pre-desulfurization device 10 can be operated at normal temperature and pressure, and has the characteristics of simple operation and high efficiency. Sodium arsenite (NaAsO2) is an active component (the dosage is generally a few grams / liter) and plays a catalytic role to improve the regeneration efficiency and reaction rate: it is reduced to arsenic when absorbing H2S, and is oxidized back to sodium arsenite when in contact with air, and this cycle is repeated.

[0102] Of course, the pre-desulfurization device can also use the same desulfurization device as the desulfurization device 9. In an optional embodiment, the desulfurization device 9 is a desulfurization tower, and a plurality of reactors are distributed in the desulfurization tower, some of which are used as reactors of the pre-desulfurization device, and the other part are used as reactors of the desulfurization device 9.

[0103] The above is a description of the relevant contents of the present invention. A person skilled in the art will be able to implement the present invention based on these descriptions. Based on the above contents of this specification, all other embodiments obtained by a person skilled in the art without making creative work should fall within the scope of the present invention.

Claims

1. A method for dephosphorization and desulfurization of yellow phosphorus tail gas, characterized in that: include: Passing yellow phosphorus tail gas into a dephosphorization device to remove phosphorus-containing substances in the yellow phosphorus tail gas, wherein the dephosphorization device adopts a first catalytic flue gas treatment device, wherein the first catalytic flue gas treatment device comprises a first reactor, wherein the yellow phosphorus tail gas enters the first reactor from an air inlet of the first reactor, passes through a first catalyst, and is then discharged from an exhaust port of the first reactor to become dephosphorized flue gas, wherein PH3 and P4 in the yellow phosphorus tail gas react on the first catalyst to form phosphorus oxides and phosphoric acid when passing through the first catalyst, and when the first catalyst is washed and regenerated, the phosphorus oxides and the phosphoric acid enter a regeneration liquid sprayed on the first catalyst and are then discharged from a liquid discharge port of the first reactor; The dephosphorized flue gas is passed through an organic sulfur hydrolysis conversion device to convert organic sulfur in the dephosphorized flue gas into H2S. The organic sulfur hydrolysis conversion device adopts a second catalytic flue gas treatment device. The second catalytic flue gas treatment device comprises a second reactor. When working, the dephosphorized flue gas enters the second reactor from the air inlet of the second reactor, passes through the second catalyst, and is discharged from the exhaust port of the second reactor to become organic sulfur hydrolysis conversion flue gas. The organic sulfur in the dephosphorized flue gas is hydrolyzed and converted into H2S when passing through the second catalyst. The organic sulfur hydrolysis conversion flue gas is passed into a desulfurization device to remove H2S in the organic sulfur hydrolysis conversion flue gas. The desulfurization device adopts a third catalytic flue gas treatment device, and the third catalytic flue gas treatment device includes a third reactor. During operation, the organic sulfur hydrolysis conversion flue gas enters the third reactor from the air inlet of the third reactor, passes through the third catalyst, and is then discharged from the exhaust port of the third reactor to become desulfurized flue gas. The H2S in the organic sulfur hydrolysis conversion flue gas reacts on the third catalyst to form elemental S and sulfuric acid when passing through the third catalyst. The sulfuric acid is generated by further catalytic oxidation of sulfur dioxide generated by the reaction of the elemental S with oxygen and reacting with water. When the third catalyst is washed and regenerated, the elemental S and the sulfuric acid enter the regeneration liquid sprayed on the third catalyst and are discharged from the discharge port of the third reactor.

2. The method for dephosphorization and desulfurization of yellow phosphorus tail gas as claimed in claim 1, characterized in that: The operating conditions of the first reactor are: 1) First catalyst formula: The first catalyst is mainly composed of the following components in parts by weight uniformly mixed: Nano PdO particles: 0.8-1.2 parts; Nano PtO2 particles: 0.4-0.6 parts; CeO2: 3.5-4.5 parts; V2O5: 2.5-3.5 parts; Activated carbon carrier: 90-93 parts; Wherein, the weight ratio of nano-PdO particles to nano-PtO2 particles is (1.8-2):1, and the weight ratio of CeO2 to V2O5 is (1.2-1.5):1; 2) Operation parameters of the first reactor: operate at 100-120℃, control the air velocity to 1000-2000h -1 , O2 concentration in the gas phase is 5-8% (v / v%), and the moisture content is less than 2% (v / v%).

3. The method for dephosphorization and desulfurization of yellow phosphorus tail gas as claimed in claim 1, characterized in that: The operating conditions of the second reactor are: 1) Second catalyst formula: The second catalyst is mainly composed of the following components in parts by weight uniformly mixed: CeO2: 5-7 parts; V2O5: 3-4 parts; MoO3: 2-3 parts; γ-Al2O3 carrier: 86-90 parts; Among them, the weight ratio of CeO2 to V2O5 is (1.6-1.8):1, and the weight ratio of V2O5 to MoO3 is (1.4-1.6):1; 2) Operation parameters of the second reactor: operate at 70-90°C and control the air velocity to 1000-2000h -1 , the moisture content is 15-20% (v / v%).

4. The method for dephosphorization and desulfurization of yellow phosphorus tail gas as claimed in claim 1, characterized in that: The operating conditions of the third reactor are: 1) The third catalyst formula: The third catalyst is mainly composed of the following components in parts by weight uniformly mixed: Fe2O3: 3-5 parts; CuO: 2-3 parts; MnO2: 1-2 parts; Activated carbon carrier: 90-94 parts; Wherein, the weight ratio of Fe2O3 to CuO is (1.5-1.8):1, and the weight ratio of CuO to MnO2 is (1.8-2.0):1; 2) Operation parameters of the third reactor: Run at 65-85℃, control airspeed at 800-1500h -1 , the O2 concentration in the gas phase is 3-5% (v / v%), and the moisture content is 2-8% (v / v%).

5. The method for dephosphorization and desulfurization of yellow phosphorus tail gas according to any one of claims 1 to 4, characterized in that: The yellow phosphorus tail gas is subjected to leaching pretreatment before being sent to the dephosphorization device; the leaching pretreatment includes passing the yellow phosphorus tail gas into a first leaching system for water leaching treatment and / or passing the yellow phosphorus tail gas into a second leaching system for alkaline solution leaching treatment.

6. The method for dephosphorization and desulfurization of yellow phosphorus tail gas as claimed in claim 5, characterized in that: The yellow phosphorus tail gas after the leaching pretreatment is successively subjected to gas-liquid separation treatment and heating, and then sent to the dephosphorization device.

7. Yellow phosphorus tail gas dephosphorization and desulfurization equipment, characterized by: include: A dephosphorization device is used to receive yellow phosphorus tail gas and remove phosphorus-containing substances in the yellow phosphorus tail gas. The dephosphorization device adopts a first catalytic flue gas treatment device. The first catalytic flue gas treatment device includes a first reactor. When working, the yellow phosphorus tail gas enters the first reactor from the air inlet of the first reactor, passes through the first catalyst, and is then discharged from the exhaust port of the first reactor to become dephosphorized flue gas. PH3 and P4 in the yellow phosphorus tail gas react on the first catalyst to form phosphorus oxides and phosphoric acid when passing through the first catalyst. When the first catalyst is washed and regenerated, the phosphorus oxides and the phosphoric acid enter the regeneration liquid sprayed on the first catalyst and are discharged from the discharge port of the first reactor. An organic sulfur hydrolysis conversion device is used to receive the dephosphorized flue gas and convert the organic sulfur in the dephosphorized flue gas into H2S. The organic sulfur hydrolysis conversion device adopts a second catalytic flue gas treatment device. The second catalytic flue gas treatment device includes a second reactor. When working, the dephosphorized flue gas enters the second reactor from the air inlet of the second reactor, passes through the second catalyst, and is discharged from the exhaust port of the second reactor to become organic sulfur hydrolysis conversion flue gas. The organic sulfur in the dephosphorized flue gas is hydrolyzed and converted into H2S when passing through the second catalyst. A desulfurization device is used to receive the organic sulfur hydrolysis conversion flue gas and remove H2S in the organic sulfur hydrolysis conversion flue gas. The desulfurization device adopts a third catalytic flue gas treatment device, and the third catalytic flue gas treatment device includes a third reactor. When working, the organic sulfur hydrolysis conversion flue gas enters the third reactor from the air inlet of the third reactor, passes through the third catalyst, and is then discharged from the exhaust port of the third reactor to become desulfurized flue gas. When passing through the third catalyst, the H2S in the organic sulfur hydrolysis conversion flue gas reacts on the third catalyst to form elemental S and sulfuric acid. The sulfuric acid is generated by further catalytic oxidation of sulfur dioxide generated by the reaction of the elemental S with oxygen and reacting with water. When washing and regenerating the third catalyst, the elemental S and the sulfuric acid enter the regeneration liquid sprayed on the third catalyst and are discharged from the discharge port of the third reactor.

8. The yellow phosphorus tail gas dephosphorization and desulfurization equipment according to claim 7, characterized in that:

1. The operating conditions of the first reactor are: 1) First catalyst formula: The first catalyst is mainly composed of the following components in parts by weight uniformly mixed: Nano PdO particles: 0.8-1.2 parts; Nano PtO2 particles: 0.4-0.6 parts; CeO2: 3.5-4.5 parts; V2O5: 2.5-3.5 parts; Activated carbon carrier: 90-93 parts; Wherein, the weight ratio of nano-PdO particles to nano-PtO2 particles is (1.8-2):1, and the weight ratio of CeO2 to V2O5 is (1.2-1.5):1; 2) Operation parameters of the first reactor: operate at 100-120℃, control the air velocity to 1000-2000h -1 , O2 concentration in the gas phase is 5-8% (v / v%), and the moisture content is less than 2% (v / v%); 2. The operating conditions of the second reactor are: 1) Second catalyst formula: The second catalyst is mainly composed of the following components in parts by weight uniformly mixed: CeO2: 5-7 parts; V2O5: 3-4 parts; MoO3: 2-3 parts; γ-Al2O3 carrier: 86-90 parts; Among them, the weight ratio of CeO2 to V2O5 is (1.6-1.8):1, and the weight ratio of V2O5 to MoO3 is (1.4-1.6):1; 2) Operation parameters of the second reactor: operate at 70-90°C and control the air velocity to 1000-2000h -1 , moisture content is 15-20% (v / v%); 3. The operating conditions of the third reactor are: 1) The third catalyst formula: The third catalyst is mainly composed of the following components in parts by weight uniformly mixed: Fe2O3: 3-5 parts; CuO: 2-3 parts; MnO2: 1-2 parts; Activated carbon carrier: 90-94 parts; Wherein, the weight ratio of Fe2O3 to CuO is (1.5-1.8):1, and the weight ratio of CuO to MnO2 is (1.8-2.0):1; 2) Operation parameters of the third reactor: Run at 65-85℃, control airspeed at 800-1500h -1 , the O2 concentration in the gas phase is 3-5% (v / v%), and the moisture content is 2-8% (v / v%).

9. The yellow phosphorus tail gas dephosphorization and desulfurization equipment according to claim 7, characterized in that: It comprises a leaching pretreatment device, which is arranged before the dephosphorization device and is used for leaching and pretreating the yellow phosphorus tail gas before sending it into the dephosphorization device; the leaching pretreatment comprises a first leaching system and / or a second leaching system, the first leaching system is used for leaching the yellow phosphorus tail gas with water, and the second leaching system is used for leaching the yellow phosphorus tail gas with an alkaline solution.

10. The method for dephosphorization and desulfurization of yellow phosphorus tail gas according to claim 9, characterized in that: The first elution system comprises at least two first elution towers, and the second elution system comprises at least one second elution tower, wherein the second elution tower is arranged in series after the at least two first elution towers; And / or, a gas-liquid separation device and a gas heating device are sequentially arranged between the elution pretreatment device and the dephosphorization device.

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