Integrated catalytic hydrolysis desulfurization tower, integrated dry purification device and method

Abstract

The present invention relates to an integrated catalytic hydrolysis desulfurization tower, an integrated dry purification device and method, belonging to the field of pollutant control technology in environmental protection engineering technology. The integrated catalytic hydrolysis desulfurization tower includes a gas inlet, a tower shell, a catalytic hydrolysis section, a desulfurization section and a clean blast furnace gas discharge outlet. The gas inlet is arranged at the top of the catalytic hydrolysis desulfurization tower and is connected to the inlet flue of the catalytic hydrolysis desulfurization tower, and is used for sending blast furnace gas into the catalytic hydrolysis section. The clean blast furnace gas outlet is arranged at the bottom of the catalytic hydrolysis desulfurization tower and is used for discharging the blast furnace gas purified by the integrated catalytic hydrolysis desulfurization tower. The catalytic hydrolysis section is filled with a hydrolysis catalyst, which is used for hydrolyzing and catalyzing the blast furnace gas introduced from the gas inlet. The desulfurization section is filled with a desulfurizer, and the desulfurizer is used for absorbing the sulfur-containing gas in the blast furnace gas after hydrolysis and catalytic treatment in the catalytic hydrolysis section. Thus, the removal of sulfur-containing substances in the blast furnace gas is realized, and the problem of excessive sulfur dioxide is solved from the source.

Description

Technical Field

[0001] The present invention relates to the technical field of pollutant control in environmental protection engineering technology, and particularly relates to an integrated catalytic hydrolysis desulfurization tower, an integrated dry purification device and a method for removing sulfur-containing substances in blast furnace gas, which are used to achieve the total sulfur removal of blast furnace gas in a set of processes. Background Art

[0002] As the combustible gas with the largest output in iron and steel enterprises, the statistical output of blast furnace gas is as high as 70 - 80 billion cubic meters per month. The existing purification and subsequent application of blast furnace gas mainly use bag filters to remove particulate matter. After that, through TRT residual pressure power generation, it is sent to user units such as blast furnace hot stoves, rolling heating furnaces, and gas power generation as fuel. However, harmful substances such as sulfur and chlorine still exist in blast furnace gas. With the promulgation of the "Opinions on Promoting the Implementation of Ultra-low Emissions in the Iron and Steel Industry", the iron and steel industry has officially entered the "ultra-low emission" era. User units such as blast furnace hot stoves, rolling heating furnaces, and gas power generation all require that the SO2 in the combustion exhaust gas reach ultra-low emission limits, while the existing blast furnace gas purification process cannot meet the SO2 control requirements.

[0003] The current technical routes mainly include source control and end treatment after combustion. For example, if the end treatment method is adopted, desulfurization facilities need to be set up at multiple points. At the same time, the exhaust gas volume after gas combustion is large, and the scale of the treatment facilities becomes larger; if the source control method is adopted, centralized treatment can be carried out, and the gas volume to be treated is only about 60% of the flue gas volume after combustion. Therefore, the total investment is low, the total floor area is small, the operating cost is low, and the management is convenient. At the same time, source treatment promotes the service life of the pipeline network and the combustion efficiency. Implementing the total sulfur removal of blast furnace gas and reducing the sulfur content in the gas can greatly reduce the pressure of end treatment and even eliminate the end treatment facilities.

[0004] The total sulfur removal of blast furnace gas is a new technical development direction. At present, there are many single organic sulfur hydrolysis technologies and dry adsorption and removal technologies, and there are also relevant application examples for blast furnace gas dechlorination technology. However, there is no report or engineering case on the total sulfur removal technology of blast furnace gas. Therefore, the total sulfur removal technology of blast furnace gas is still in the stage of frontier exploration. Summary of the Invention

[0005] The purpose of the present invention is to provide an integrated catalytic hydrolysis desulfurization tower, an integrated dry purification device and a method for achieving the total sulfur removal of blast furnace gas, preferably an integrated catalytic hydrolysis desulfurization tower, an integrated dry purification device and a method for removing sulfur-containing substances such as COS, CS2, H2S, SO2, etc. in blast furnace gas and synergistically removing HCl, so as to solve the above technical problems.

[0006] According to one aspect of the present invention, there is provided an integrated catalytic hydrolysis desulfurization tower for realizing the total sulfur removal of blast furnace gas, characterized in that: the integrated catalytic hydrolysis desulfurization tower includes: a gas inlet, a tower shell, a catalytic hydrolysis section, a desulfurization section and a clean blast furnace gas outlet, wherein: the gas inlet is arranged at the top of the integrated catalytic hydrolysis desulfurization tower and is connected to the inlet flue of the integrated catalytic hydrolysis desulfurization tower for feeding the blast furnace gas into the catalytic hydrolysis section, and the clean blast furnace gas outlet is arranged at the bottom of the integrated catalytic hydrolysis desulfurization tower for discharging the blast furnace gas purified by the integrated catalytic hydrolysis desulfurization tower, and wherein: the catalytic hydrolysis section of the integrated catalytic hydrolysis desulfurization tower is filled with a hydrolysis catalyst for catalytically hydrolyzing the blast furnace gas introduced from the gas inlet; the desulfurization section of the integrated catalytic hydrolysis desulfurization tower is filled with a desulfurizing agent for absorbing the sulfur-containing gas in the blast furnace gas after catalytic hydrolysis treatment in the catalytic hydrolysis section.

[0007] According to another aspect of the present invention, there is provided an integrated dry purification device for realizing the total sulfur removal of blast furnace gas, characterized in that it includes a pneumatic conveying device and at least one of the above-mentioned integrated catalytic hydrolysis desulfurization towers, wherein the pneumatic conveying device is connected to the at least one integrated catalytic hydrolysis desulfurization tower for feeding the desulfurizing agent into the desulfurization section.

[0008] According to still another aspect of the present invention, there is provided an integrated dry purification method for realizing the total sulfur removal of blast furnace gas, characterized by including the following steps: catalytic hydrolysis treatment, feeding the inlet blast furnace gas into the catalytic hydrolysis section of the integrated catalytic hydrolysis desulfurization tower, and catalytically converting the carbonyl sulfide and carbon disulfide in the blast furnace gas into hydrogen sulfide through the catalyst filled in the catalytic hydrolysis section; desulfurization treatment, the generated hydrogen sulfide enters the desulfurization section of the integrated catalytic hydrolysis desulfurization tower along with the blast furnace gas, and the desulfurizing agent filled in the desulfurization section absorbs hydrogen sulfide, sulfur dioxide, hydrogen chloride to remove the sulfur-containing substances and hydrogen chloride in the blast furnace gas; and discharging the clean blast furnace gas, the blast furnace gas after being treated by the integrated catalytic hydrolysis desulfurization tower is discharged through the clean blast furnace gas outlet of the integrated catalytic hydrolysis desulfurization tower.

[0009] Correspondingly, through the present invention, the treated clean gas is discharged from the bottom of the tower and incorporated into the pipe network, thereby realizing the removal of sulfur-containing substances in the blast furnace gas and solving the problem of excessive SO2 from the source.

[0010] In addition, in the present invention, COS and CS2 in the blast furnace gas are catalytically converted into H2S in the catalytic hydrolysis section; the desulfurizing agent in the desulfurization section absorbs the sulfur-containing gas in the gas, thereby realizing the removal of sulfur-containing substances in the blast furnace gas. More preferably, the desulfurizing agent in the desulfurization section absorbs acidic gases such as H2S, SO2, HCl in the gas, thereby the synergistic removal of HCl controls the problem of gas pipeline corrosion to a certain extent.

[0011] The present invention provides an integrated catalytic hydrolysis desulfurization tower, an integrated dry purification device and a method for desulfurization in blast furnace gas, which have a simple technical process, low cost and good reliability, and can especially realize desulfurization in the temperature range of 40 - 150°C.

[0012] In addition: The present invention also provides an integrated catalytic hydrolysis desulfurization tower, an integrated dry purification device and a method for simultaneously removing H2S, SO2, HCl and other acidic gases in blast furnace gas. In the integrated dry purification method of the present invention, organic sulfur such as COS and CS2 is first catalytically converted into H2S, and then acidic gases such as H2S, SO2, and HCl in the gas are absorbed by the desulfurizer in the desulfurization section. This method can provide steel mills and environmental protection companies with accurate process layout plans and operating parameters for controlling sulfur pollutants in blast furnace gas, solve the problem of excessive SO2 from the source, and at the same time, the co-removal of HCl controls the corrosion problem of gas pipelines to a certain extent. The process is simple, has good reliability, stable operation, and reduces the cost of pollutant control. Brief Description of the Drawings

[0013] Figure 1 is a structural diagram of the integrated catalytic hydrolysis desulfurization tower for realizing total sulfur removal in blast furnace gas according to the present invention;

[0014] Figure 2 is an operation schematic diagram of the integrated dry purification device for realizing total sulfur removal in blast furnace gas according to the present invention;

[0015] Figure 3 is a layout diagram of the integrated dry purification device for realizing total sulfur removal in blast furnace gas according to the present invention;

[0016] Figure 4 is a flow chart of the integrated dry purification method for realizing total sulfur removal in blast furnace gas according to the present invention; and

[0017] Figure 5 is a process diagram of the integrated dry purification method for realizing total sulfur removal in blast furnace gas according to the present invention. Detailed Embodiments

[0018] The present invention will now be described in detail with reference to the accompanying drawings, in which the same reference numerals denote the same components, and: 1 - inlet blast furnace gas, 2 - feeding port of the catalytic hydrolysis section, 3 - catalyst support mesh, 4 - discharging port of the catalytic hydrolysis section, 5 - desulfurizer inlet, 6 - inlet shut-off valve 1, 7 - inlet buffer bin, 8 - purge gas interface 1, 9 - gas purge valve 1, 10 - inlet shut-off valve 2, 11 - venting interface 1, 12 - venting valve 1, 13 - observation window, 14 - reaction chamber, 15 - rapping motor, 16 - outlet shut-off valve 1, 17 - venting valve 2, 18 - venting interface 2, 19 - outlet buffer bin, 20 - outlet shut-off valve 2, 21 - desulfurizer outlet, 22 - purge gas interface 2, 23 - gas purge valve 2, 24 - desulfurizer support mesh, 25 - blast furnace gas discharge port, 26 - inlet gas cut-off valve 1, 27 - inlet gas cut-off valve 2, 28 - outlet gas cut-off valve 1, 29 - outlet gas cut-off valve 2, 30 - pneumatic conveying device, 31 - inspection hole, 32 - venting valve 3, 33 - gas purge valve 3, 34 - gas inlet, 35 - gas outlet, 36 - tower shell.

[0019] As Figure 1 shown, the integrated catalytic hydrolysis desulfurization tower for realizing the total sulfur removal of blast furnace gas according to the present invention includes a gas inlet 34, a tower shell 36, a catalytic hydrolysis section, a desulfurization section, and a blast furnace gas outlet 35. The gas inlet 34 at the top of the tower shell is connected to the inlet flue of the integrated catalytic hydrolysis desulfurization tower for feeding blast furnace gas into the catalytic hydrolysis section; the blast furnace gas outlet 35 is arranged below the desulfurization section for discharging the blast furnace gas purified by the integrated catalytic hydrolysis desulfurization tower.

[0020] The catalytic hydrolysis section has a catalyst support mesh 3, a catalyst feeding port 2, a catalyst discharging port 4, and an inspection hole 31; the catalyst support mesh 3 is arranged inside the tower shell for supporting the hydrolysis catalyst; the feeding port 2 and the discharging port 4 are arranged on the tower shell for feeding and discharging the hydrolysis catalyst, and an inspection hole 31 is arranged above the catalytic hydrolysis section for maintenance personnel to enter the tower for maintenance under accident conditions.

[0021] The desulfurization section is provided with a reaction chamber 14, and preferably also includes an online desulfurizer replacement system. From top to bottom in the desulfurization section, a desulfurizer inlet 5, an inlet shut-off valve 1, an inlet buffer bin 7, an inlet shut-off valve 2, an outlet shut-off valve 1, an outlet buffer bin 19, an outlet shut-off valve 2, and a desulfurizer outlet 21 are sequentially arranged; replacement gas interfaces 1 and 2, and vent interfaces 1 and 2 are respectively arranged on the sides of the inlet buffer bin 7 and the outlet buffer bin 19, which are used to displace and vent the coal gas in the buffer bin with nitrogen or other inert gases before replacing the desulfurizer to ensure site safety. Vibration motors 15 are arranged on both sides of the inlet buffer bin 7, the reaction chamber 14, and the outlet buffer bin 19 to vibrate the bin wall regularly to maintain the fluidized state of the desulfurizer. An observation hole 13 is arranged on the tower wall between the desulfurization section and the catalytic hydrolysis section to observe the situation inside the bin in real time during operation. A desulfurizer support mesh 24 is arranged below the reaction chamber of the desulfurization section to support the desulfurizer, and a blast furnace gas outlet 35 is arranged below the desulfurizer support mesh 24 to discharge the blast furnace gas purified by the reaction tower.

[0022] In the present invention, the catalytic hydrolysis section has an inlet flue, a catalyst support mesh 3, a catalyst feeding port 2, a catalyst discharging port 4, and a maintenance hole 31. The top of the tower shell is connected to the inlet flue of the integrated catalytic hydrolysis desulfurization tower, which is used to send blast furnace gas into the catalytic hydrolysis section; the catalyst support mesh 4 is arranged inside the tower shell to support the hydrolysis catalyst; a feeding port 2 and a discharging port 4 are arranged on the tower shell, which are used to feed and discharge the hydrolysis catalyst, and a maintenance hole 31 is arranged above the catalytic hydrolysis section, which is used for maintenance personnel to enter the tower for maintenance under accident conditions.

[0023] Preferably, in the present invention, the catalyst is one or more of honeycomb, rod-shaped, Raschig ring-shaped, and spherical. The organic sulfur such as carbonyl sulfide (COS) and carbon disulfide (CS2) in the blast furnace gas is catalytically hydrolyzed and converted into H2S. The active components of the catalyst are one or more of Na, K, Fe, Cu, and Ni salts, and the carrier is one or more of activated alumina, activated carbon, cordierite, and hydrotalcite-like.

[0024] When the catalyst configuration is a Raschig ring-shaped catalyst, it is preferably randomly stacked from large to small on the catalyst support mesh (3) in the catalytic hydrolysis section during catalyst loading, so that the catalytic reaction space velocity is 500 - 4000h -1 , and the coal gas flow velocity is 0.5 - 2 m / s; preferably, 80% - 95% by volume of carbonyl sulfide (COS) and carbon disulfide (CS2) in the blast furnace gas are catalytically converted into H2S in the catalytic hydrolysis section.

[0025] Preferably, the gas pressure drop in the desulfurization section is low, the desulfurizer has little wear, the gas-solid two-phase contact is uniform, and the adjustment flexibility of the desulfurizer residence time is large. The gas flow rate in the desulfurization section is controlled at 0.5 - 3 m / s to ensure uniform air distribution; preferably, the inlet temperature of blast furnace gas is 40 - 150 °C, and the outlet temperature remains basically unchanged.

[0026] Preferably, in the present invention, the desulfurizer is in a porous columnar shape, the carrier is a mixture of zeolite and pumice, and the molar ratio of pumice to zeolite is between 0.2 - 0.5; the active components are mainly one or more of iron oxide, manganese oxide, potassium hydroxide, and sodium carbonate, and the mass fraction of the active components in the desulfurizer is 3% - 10%. The desulfurizer is filled with a certain volume to make the desulfurization reaction space velocity 500 - 5000 h -1 , to ensure the efficient removal of pollutants in blast furnace gas.

[0027] As Figure 2 , 3 shown, an integrated dry purification device capable of achieving total sulfur removal from blast furnace gas, preferably an integrated dry purification device capable of removing sulfur-containing substances such as COS, CS2, H2S, SO2, etc. in blast furnace gas and synergistically removing HCl, includes a pneumatic conveying device 30 and at least one integrated catalytic hydrolysis desulfurization tower; the pneumatic conveying device 30 is connected to the integrated catalytic hydrolysis desulfurization tower for feeding the desulfurizer into the desulfurization section of the integrated catalytic hydrolysis desulfurization tower; the catalytic hydrolysis section of the integrated catalytic hydrolysis desulfurization tower is filled with a hydrolysis catalyst for hydrolytic catalysis of the blast furnace gas introduced from the upper part of the tower, and the desulfurization section is filled with a desulfurizer for absorbing hydrogen sulfide (H2S), sulfur dioxide (SO2), hydrogen chloride (HCl), and other acidic gases in the blast furnace gas after hydrolytic catalytic treatment. A clean blast furnace gas outlet 35 is provided at the bottom of the tower for discharging the blast furnace gas after being treated by the integrated catalytic hydrolysis desulfurization tower through the clean blast furnace gas discharge outlet and sending it into the blast furnace gas pipeline network.

[0028] As Figure 2 , 3As shown, there are 4 integrated catalytic hydrolysis desulfurization towers with 3 in operation and 1 in standby. During operation, the switching of the reaction towers is achieved by opening and closing the inlet gas cut-off valves 1 and 2 and the outlet gas cut-off valves 1 and 2 for the blast furnace gas. The 4 towers take turns to replace the desulfurizer at certain time intervals to ensure the desulfurization effect. During normal operation, the inlet shut-off valves 6 and 10 and the outlet shut-off valves 16 and 20 are all in the closed state. If the desulfurizer needs to be replaced, first open the outlet shut-off valve 16 to discharge the desulfurizer in the reaction chamber 14 into the outlet buffer chamber 19, then close the outlet shut-off valve 16, open the gas displacement valve 23 and the bleed valve 17, and introduce nitrogen or other inert gases into the outlet buffer chamber 19 to displace the gas in the chamber and bleed it; then close the gas displacement valve 23 and the bleed valve 17, open the outlet shut-off valve 20, and discharge the desulfurizer in the outlet buffer chamber 19 through the desulfurizer outlet 21 and transport it away by truck, and close the outlet shut-off valve 20; next, add the desulfurizer transported by the truck to the desulfurizer inlet 5 through the pneumatic conveying device 30, open the gas displacement valve 9 and the bleed valve 12, introduce nitrogen or other inert gases into the inlet buffer chamber 7 to displace the gas in the chamber and bleed it; then close the gas displacement valve 9 and the bleed valve 12, open the inlet shut-off valve 6 to discharge the desulfurizer into the inlet buffer chamber 7, close the inlet shut-off valve 6, open the inlet shut-off valve 10 to discharge the desulfurizer into the reaction chamber 14, and close the inlet shut-off valve 10 to complete the desulfurizer replacement process. The use of buffer chambers and gas displacement can prevent the leakage of blast furnace gas and ensure the safe operation of the system. If the integrated catalytic hydrolysis desulfurization tower needs to be overhauled, after emptying the desulfurizer in the aforementioned manner, close the inlet shut-off valve 6, the outlet shut-off valve 20, the gas inlet cut-off valves 26 and 27, and the gas outlet cut-off valves 28 and 29, open the inlet shut-off valve 10 and the outlet shut-off valve 16, open the gas displacement valves 9, 23, and 33 and the bleed valves 12, 17, and 32, introduce nitrogen or other inert gases into the entire tower to displace the gas in the tower and bleed it, and then purge the entire system with compressed air to ensure the safety of the maintenance personnel.

[0029] Preferably, in the present invention, the configuration of the catalyst is one or more of honeycomb, rod, Raschig ring, and spherical. The organic sulfur such as carbonyl sulfide (COS) and carbon disulfide (CS2) in the blast furnace gas is catalytically hydrolyzed and converted into H2S. The active components of the catalyst are one or more of Na, K, Fe, Cu, and Ni salts, and the carrier is one or more of activated alumina, activated carbon, cordierite, and hydrotalcite-like. The catalyst with a Raschig ring configuration is randomly stacked from large to small on the catalyst support mesh 3 in the catalytic hydrolysis section. The catalyst is loaded so that the catalytic reaction space velocity is 500 - 4000h -1, the coal gas flow rate is 0.5 - 2 m / s; preferably, in the catalytic hydrolysis section, 80% - 95% by volume of carbonyl sulfide (COS) and carbon disulfide (CS2) in the blast furnace gas are catalytically converted into H2S. The desulfurization section has a low gas pressure drop, less wear of the desulfurizer, uniform gas-solid two-phase contact, and a large adjustment elasticity of the desulfurizer residence time. The gas flow rate in the desulfurization section is controlled at 0.5 - 3 m / s to ensure uniform air distribution; preferably, the inlet temperature of the blast furnace gas is 40 - 150 °C, and the outlet temperature remains basically unchanged. The desulfurizer is in a porous column shape, and the carrier is a mixture of zeolite and pumice, and the molar ratio of pumice to zeolite is between 0.2 - 0.5; the active components are mainly one or more of iron oxide, manganese oxide, potassium hydroxide, and sodium carbonate, and the active components account for 3% - 10% of the mass of the desulfurizer. The desulfurizer is filled with a certain volume so that the desulfurization reaction space velocity is 500 - 5000 h -1 , ensuring the efficient removal of pollutants in the blast furnace gas.

[0030] It should be noted that although the above description mentions an integrated dry purification device including 4 integrated catalytic hydrolysis desulfurization towers 3 with 3 in use and 1 standby, the integrated dry purification device of the present invention can of course also include only 1 integrated catalytic hydrolysis desulfurization tower and still achieve the desulfurization purpose.

[0031] Next, specifically refer to Figure 4 to describe a dry purification method for the full sulfur removal of blast furnace gas according to the present invention, preferably a dry purification method for the removal of sulfur-containing substances such as COS, CS2, H2S, and SO2 in the blast furnace gas and the co-removal of HCl, preferably, the purification method uses Figure 2 , 3 as shown, an integrated dry purification device for the full sulfur removal of blast furnace gas; the integrated dry purification method of the present invention includes the following steps:

[0032] (1) The inlet blast furnace gas 1 first enters the catalytic hydrolysis section of the integrated catalytic hydrolysis desulfurization tower for treatment, and COS and CS2 in the blast furnace gas are catalytically converted into H2S by the catalyst filled in the catalytic hydrolysis section;

[0033] (2) The generated H2S enters the desulfurization section with the blast furnace gas, and the desulfurizer is sent into the desulfurization section through the pneumatic conveying system 30 to absorb H2S, SO2, HCl and other acidic gases, achieving the removal of sulfur-containing substances in the blast furnace gas;

[0034] (3) The blast furnace gas treated by the integrated catalytic hydrolysis desulfurization tower is discharged through the clean blast furnace gas discharge port 25 and sent into the blast furnace gas pipeline network, thereby realizing the desulfurization of the blast furnace gas.

[0035] Preferably, during the operation process, the replacement frequency of the desulfurizer is adjusted according to the concentration of H2S in the outlet gas, so as to remove sulfur-containing substances in the blast furnace gas, solve the problem of excessive SO2 from the source, and at the same time, the co-removal of HCl controls the corrosion problem of the gas pipeline to a certain extent.

[0036] The process of the present invention is as Figure 5 shown: The combustible gas (containing nitrogen (N2), carbon monoxide (CO), carbon dioxide (CO2), hydrogen (H2), hydrocarbons, a small amount of sulfur-containing compounds and dust) by-produced during the blast furnace ironmaking production process, after gravity dust removal, bag dust removal, and a top pressure recovery turbine (TRT), is used as the inlet blast furnace gas 1 of the purification method described in the present invention. The blast furnace gas passes through an integrated catalytic hydrolysis desulfurization tower. In the upper half of the tower, the catalytic hydrolysis section is filled with a catalyst. The catalyst uses one or more of activated alumina, activated carbon, cordierite, and hydrotalcite-like compounds as carriers, and one or more of Na, K, Fe, Cu, and Ni salts as active components. The catalyst configuration is a Raschig ring catalyst. The catalyst is filled so that the catalytic reaction space velocity is 500 - 4000h -1 , the gas flow rate is 0.5 - 2m / s, so that in the catalytic hydrolysis section, 80% - 95% by volume of COS and CS2 in the blast furnace gas are catalytically converted into H2S, and then enter Figure 2 the lower half of the tower, the desulfurization section. The desulfurization section is filled with a desulfurizer. The desulfurizer is a porous column type, and the carrier is a mixture of zeolite and pumice. The molar ratio of pumice to zeolite is between 0.2 - 0.5; the main active components are one or more of iron oxide, manganese oxide, potassium hydroxide, and sodium carbonate, and the active components account for 3% - 10% of the mass of the desulfurizer. The desulfurizer is filled with a certain volume so that the desulfurization reaction space velocity is 500 - 5000h -1 , ensuring the efficient removal of pollutants in the blast furnace gas.

[0037] In the catalytic hydrolysis section, the blast furnace gas and moisture react under the action of the catalyst as follows:

[0038] COS + H20 = CO2 + H2S;

[0039] CS2 + H20 = COS + H2S;

[0040] CS2 + 2H2O = 2H2S + CO2.

[0041] Subsequently, the H2S generated by the reaction and a small amount of acidic gases such as HCl and SO2 originally present in the blast furnace gas react with the desulfurizer in the desulfurization section as follows:

[0042] Fe2O3.H2O + 3H2S = Fe2S3.H2O + 3H2O

[0043] MnO + H2S = MnO + H2O

[0044] H2S + 2KOH = K2S + 2H2O, SO2 + 2KOH = K2SO3 + H2O, HCl + KOH = KCl + H2O

[0045] H2S + 2Na2CO3 = Na2S + 2NaHCO3, SO2 + 2Na2CO3 + H2O = 2NaHCO3 + Na2SO3,

[0046] HCl + Na2CO3 = NaCl + NaHCO3

[0047] In the presence of O2, Na2SO3 can be oxidized to Na2SO4.

[0048] Example:

[0049] For the blast furnace gas of a steel mill, the purification device and method of the present invention are used. The temperature of the gas at the inlet of the integrated catalytic hydrolysis desulfurization tower is 90 °C, the contents of COS and CS2 are 120 mg / Nm 3 , the content of H2S is 50 mg / Nm 3 , the inlet gas flow rate is 5000 Nm 3 / h, the catalyst is filled in the catalytic hydrolysis section with a volume of 2.5 m 3 , the cross-sectional area of the catalyst perpendicular to the gas flow direction is 1.5 m 2 , the gas flow rate in the catalytic hydrolysis section is 1 m / s. After passing through the catalytic hydrolysis section, the proportion of COS and CS2 catalytically converted into H2S is 91%. The generated H2S enters the desulfurization section with the blast furnace gas. The gas channel in the desulfurization section is circular with a diameter of 1.5 m, and the apparent gas flow rate is 0.9 m / s. A total of 4 integrated catalytic hydrolysis desulfurization towers are set up, 3 are in use and 1 is in reserve. The total volume of a single tower is 10 m 3 , and the temperature of the gas at the outlet is 85 °C. After this dry purification process, the conversion efficiency of COS and CS2 is greater than 90%, and the outlet H2S concentration is lower than 15 mg / Nm 3 .

[0050] The above-described embodiments are only preferred embodiments given to fully illustrate the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or transformations made by those skilled in the art on the basis of the present invention are all within the protection scope of the present invention. The protection scope of the present invention is subject to the claims.

Claims

1. An integrated catalytic hydrolysis desulfurization tower for realizing the complete desulfurization of blast furnace gas, characterized in that: The integrated catalytic hydrolysis desulfurization tower includes: a gas inlet (34), a tower shell (36), a catalytic hydrolysis section, a desulfurization section, and a clean blast furnace gas outlet (35), where: The gas inlet (34) is arranged at the top of the integrated catalytic hydrolysis desulfurization tower and is connected to the inlet flue of the integrated catalytic hydrolysis desulfurization tower, for feeding blast furnace gas into the catalytic hydrolysis section, and the clean blast furnace gas outlet (35) is arranged at the bottom of the integrated catalytic hydrolysis desulfurization tower, for discharging the blast furnace gas purified by the integrated catalytic hydrolysis desulfurization tower, and where: The catalytic hydrolysis section of the integrated catalytic hydrolysis desulfurization tower is filled with a hydrolysis catalyst, for hydrolytic catalysis of the blast furnace gas introduced from the gas inlet (34), and the catalyst catalytically converts carbonyl sulfide and carbon disulfide in the blast furnace gas into hydrogen sulfide; the desulfurization section of the integrated catalytic hydrolysis desulfurization tower is filled with a desulfurizer, and the desulfurizer is used to absorb the sulfur-containing gas in the blast furnace gas after hydrolytic catalysis treatment in the catalytic hydrolysis section. The desulfurizer is in a porous column shape, and the carrier is a mixture of zeolite and pumice, and the molar ratio of pumice to zeolite is between 0.2 and 0.5; The catalytic hydrolysis section includes a catalyst support mesh (3), a catalyst feeding port (2), a catalyst discharging port (4), and an inspection hole (31), where: the catalyst support mesh (3) is arranged inside the tower shell, for supporting the hydrolysis catalyst; the catalyst feeding port (2) and the catalyst discharging port (4) are arranged on the tower shell, for feeding and discharging the hydrolysis catalyst; and the inspection hole (31) is arranged above the catalytic hydrolysis section, for maintenance personnel to enter the tower for maintenance under accident conditions; the desulfurization section is provided with a reaction chamber (14), and there is a desulfurizer support mesh (24) in the reaction chamber, for supporting the desulfurizer; and an observation hole (13) is arranged on the tower wall between the desulfurization section and the catalytic hydrolysis section, for observing the situation inside the reaction chamber (14) in real time; The integrated catalytic hydrolysis desulfurization tower further includes a desulfurizer on-line replacement system, for on-line replacement of the desulfurizer in the desulfurization section. The desulfurizer on-line replacement system includes: a desulfurizer inlet (5), an inlet shut-off valve (6), an inlet buffer bin (7), an inlet shut-off valve (10), an outlet shut-off valve (16), an outlet buffer bin (19), an outlet shut-off valve (20), and a desulfurizer outlet (21) arranged in sequence from top to bottom in the desulfurization section; and a gas replacement and venting system, which includes replacement gas interfaces (8, 22) and venting interfaces (11, 18) respectively arranged on the sides of the inlet buffer bin (7) and the outlet buffer bin (19), for replacing and venting the gas in the buffer bin with nitrogen before replacing the desulfurizer.

2. The integrated catalytic hydrolysis desulfurization tower for realizing total sulfur removal of blast furnace gas according to claim 1, characterized in that, Vibrating motors (15) are arranged on both sides of the inlet buffer bin (7), the reaction chamber (14), and the outlet buffer bin (19), for periodically vibrating each bin wall to keep the desulfurizer in a fluidized state.

3. The integrated catalytic hydrolysis desulfurization tower for realizing the complete desulfurization of blast furnace gas according to any one of claims 1-2, characterized in that, The catalyst is one or more of honeycomb, rod-shaped, Raschig ring-shaped, and spherical catalysts. The active component of the catalyst is one or more of Na, K, Fe, Cu, and Ni salts, and the carrier is one or more of activated alumina, activated carbon, cordierite, and hydrotalcite-like compounds.

4. The integrated catalytic hydrolysis desulfurization tower for realizing complete desulfurization of blast furnace gas as claimed in claim 3, wherein The catalyst has a Raschig ring configuration and is randomly stacked from large to small on the catalyst support mesh (3) in the catalytic hydrolysis section. The catalyst is loaded to achieve a catalytic reaction space velocity of 500 - 4000 h -1 , and the coal gas flow rate is 0.5 - 2 m / s.

5. The integrated catalytic hydrolysis desulfurization tower for realizing complete desulfurization of blast furnace gas according to claim 3, characterized in that, The desulfurizer is used to absorb hydrogen sulfide, sulfur dioxide, and hydrogen chloride in the blast furnace gas after hydrolysis catalytic treatment; the active components are one or more of iron oxide, manganese oxide, potassium hydroxide, and sodium carbonate, and the active components account for 3%-10% of the mass fraction of the desulfurizer. The desulfurizer is filled so that the space velocity of the desulfurization reaction is 500-5000h -1 .

6. An integrated dry purification device for realizing the total sulfur removal of blast furnace gas, characterized in that, It includes a pneumatic conveying device (30) and at least one integrated catalytic hydrolysis desulfurization tower for realizing the total sulfur removal of blast furnace gas as described in any one of the above claims 1-5. Among them, the pneumatic conveying device (30) is connected to the at least one integrated catalytic hydrolysis desulfurization tower for feeding the desulfurizer into the desulfurization section.

7. The integrated dry purification device according to claim 6, characterized in that, The integrated dry purification device includes 4 integrated catalytic hydrolysis desulfurization towers, with 3 towers in operation and 1 tower in standby. During operation, the switching of the integrated catalytic hydrolysis desulfurization towers is achieved by the opening and closing of the inlet gas cut-off valve 1 (26), inlet gas cut-off valve 2 (27), outlet gas cut-off valve 1 (28), and outlet gas cut-off valve 2 (29). The 4 towers take turns at intervals for desulfurizer replacement.

8. An integrated dry purification method for realizing the total sulfur removal of blast furnace gas, which uses the integrated catalytic hydrolysis desulfurization tower for realizing the total sulfur removal of blast furnace gas as described in any one of claims 1-5, characterized in that It includes the following steps: Catalytic hydrolysis treatment: Feed the inlet blast furnace gas into the catalytic hydrolysis section of the integrated catalytic hydrolysis desulfurization tower, and catalytically convert carbonyl sulfide and carbon disulfide in the blast furnace gas into hydrogen sulfide through the catalyst filled in the catalytic hydrolysis section. Desulfurization treatment: The generated hydrogen sulfide enters the desulfurization section of the integrated catalytic hydrolysis desulfurization tower along with the blast furnace gas. The desulfurizer filled in the desulfurization section absorbs hydrogen sulfide, sulfur dioxide, and hydrogen chloride to remove sulfur-containing substances and hydrogen chloride in the blast furnace gas. And Discharge clean blast furnace gas: The blast furnace gas after being treated by the integrated catalytic hydrolysis desulfurization tower is discharged through the clean blast furnace gas discharge port of the integrated catalytic hydrolysis desulfurization tower.

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