A cascade dry coal gas dust removal, dechlorination and desulfurization device

Abstract

The utility model relates to a cascade dry method coal gas dust removal, dechlorination and desulfurization device, including dust removal subassembly, dechlorination subassembly, hydrolytic component and desulfurization subassembly in proper order, dechlorination subassembly includes dechlorination tower and second feed pipe, second discharge pipe, second feed pipe is connected with first discharge pipe, and dechlorination tower is equipped with dechlorination packing, desulfurization subassembly includes desulfurization tower, fourth feed pipe and fourth discharge pipe, third discharge pipe is connected with fourth feed pipe, and desulfurization tower is equipped with desulfurization packing. Through the collaborative purification structure of multistage series connection, the efficient cascade removal of dust, chloride ion and sulfide in the coal gas is realized, not only solves the catalyst poisoning and equipment corrosion problem in traditional process, but also significantly improves the hydrolysis reaction efficiency through the heater, and the operation stability and purification effect are significantly improved.

Description

Technical Field

[0001] This utility model relates to the field of coal gas desulfurization, specifically to a cascade dry coal gas dust removal, dechlorination and desulfurization device. Background Technology

[0002] Before entering the desulfurization unit, blast furnace gas still contains a significant amount of dust and chloride ions, which affects subsequent hydrolysis and desulfurization processes, shortens the service life of desulfurization agents, and accelerates corrosion of pipelines, valve components, and equipment. Currently, dry desulfurization systems for blast furnace gas generally adopt a series process of "bag filter dust collection + hydrolysis catalysis + desulfurization," but this process has the following drawbacks: traditional dust collection processes are insufficient in intercepting submicron-sized dust, leading to poisoning and failure of subsequent hydrolysis catalysts; the lack of a dedicated dechlorination unit results in severe corrosion of system equipment; the absence of a precise temperature control mechanism affects the efficiency of the hydrolysis reaction; and the simple series connection of each treatment unit leads to a large system pressure drop and high energy consumption. Utility Model Content

[0003] In view of the above problems, this utility model provides a cascade dry gas dust removal, dechlorination and desulfurization device, which solves the corrosion problem caused by the high chloride ion content in existing blast furnace gas affecting the subsequent desulfurization process.

[0004] To achieve the above objectives, this application provides a cascade dry coal gas dust removal, dechlorination, and desulfurization device, including a dust removal component, a dechlorination component, a hydrolysis component, and a desulfurization component. The dust removal component includes a dust removal tower and a first feed pipe and a first discharge pipe, with the dust removal tower connected to both the first feed pipe and the first discharge pipe. The dust removal tower is equipped with dust removal packing material, which is configured as metal fiber sintered felt, nano-ceramic fiber membrane, and an oleophobic and hydrophobic coating. The dechlorination component includes a dechlorination tower and a second feed pipe and a second discharge pipe, with the dechlorination tower connected to both the second feed pipe and the second discharge pipe. The second feed pipe is connected to the first discharge pipe, and the dechlorination tower is equipped with dechlorination packing. The hydrolysis assembly includes a heater, a hydrolysis tower, a third feed pipe, and a third discharge pipe. The input end of the heater is connected to the second discharge pipe, and the output end of the heater is connected to the third feed pipe. The hydrolysis tower is connected to both the third feed pipe and the third discharge pipe. The hydrolysis tower is equipped with hydrolysis packing. The desulfurization assembly includes a desulfurization tower, a fourth feed pipe, and a fourth discharge pipe. The desulfurization tower is connected to both the fourth feed pipe and the fourth discharge pipe. The third discharge pipe is connected to the fourth feed pipe. The desulfurization tower is equipped with desulfurization packing.

[0005] In some embodiments, a first dust removal layer, a second dust removal layer, and a third dust removal layer are sequentially provided in the dust removal tower along the flow direction from the first feed pipe to the first discharge pipe; the first dust removal layer is configured as a metal fiber sintered felt; the second dust removal layer is configured as a nano-ceramic fiber membrane; and the third dust removal layer is configured as an oleophobic and hydrophobic coating.

[0006] In some embodiments, the dust removal assembly further includes a dust concentration sensor, a first pressure gauge, and a second pressure gauge. The dust concentration sensor is disposed in the first discharge pipe; the first pressure gauge is disposed in the first feed pipe; and the second pressure gauge is disposed in the first discharge pipe.

[0007] In some embodiments, the dechlorination packing is configured as a reaction packing and a protective packing; the reaction packing is configured as γ-Al2O3 spheres loaded with CuO / ZnO; and the protective packing is configured as alkali-impregnated activated carbon.

[0008] In some embodiments, the inner side of the dechlorination tower is coated with a nickel-based alloy C276.

[0009] In some embodiments, the heater is configured as a brazed plate heat exchanger; the dechlorination assembly also includes a heat pipe connected to the outside of the dechlorination tower, with the other end of the heat pipe connected to the heater.

[0010] In some embodiments, the hydrolysis packing is configured as a titanium-based catalyst; the hydrolysis tower is provided with a honeycomb ceramic structure, and the hydrolysis packing is disposed within the honeycomb ceramic structure.

[0011] In some embodiments, the desulfurization tower includes a first desulfurization zone and a second desulfurization zone, and the desulfurization packing includes a first desulfurization packing and a second desulfurization packing; the first desulfurization zone is filled with the first desulfurization packing, and the second desulfurization zone is filled with the second desulfurization packing; the input end of the first desulfurization zone is connected to a fourth feed pipe, the output end of the first desulfurization zone is connected to the input end of the second desulfurization zone, and the output end of the second desulfurization zone is connected to a fourth discharge pipe.

[0012] In some embodiments, the first desulfurization filler is configured as an iron oxide desulfurizer; the second desulfurization filler is configured as a nano-ZnO desulfurizer.

[0013] In some embodiments, the output end of the second desulfurization zone is further provided with a demister, and the output end of the demister is connected to the fourth discharge pipe.

[0014] Unlike existing technologies, the above technical solution sequentially includes a dust removal component, a dechlorination component, a hydrolysis component, and a desulfurization component. The dust removal component includes a dust removal tower, a first feed pipe, and a first discharge pipe, with dust removal packing inside the dust removal tower. The dechlorination component includes a dechlorination tower, a second feed pipe, and a second discharge pipe, with the second feed pipe connected to the first discharge pipe; the dechlorination tower also contains dechlorination packing. The hydrolysis component includes a heater, a hydrolysis tower, a third feed pipe, and a third discharge pipe, with the heater connected between the second discharge pipe and the third feed pipe; the hydrolysis tower also contains hydrolysis packing. The desulfurization component includes a desulfurization tower, a fourth feed pipe, and a fourth discharge pipe, with the third discharge pipe connected to the fourth feed pipe; the desulfurization tower also contains desulfurization packing. Through this multi-stage synergistic purification structure, efficient cascade removal of dust, chloride ions, and sulfides from coal gas is achieved. This not only solves the problems of catalyst poisoning and equipment corrosion in traditional processes but also significantly improves the hydrolysis reaction efficiency through the heater, resulting in significantly enhanced operational stability and purification effect.

[0015] The above description of the utility model is merely an overview of the technical solution of this utility model. In order to enable those skilled in the art to better understand the technical solution of this utility model and to implement it based on the description and drawings, and to make the above-mentioned objectives and other objectives, features and advantages of this utility model easier to understand, the following description is provided in conjunction with the specific embodiments and drawings of this utility model. Attached Figure Description

[0016] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, and effects of the present invention and other related contents, and should not be considered as limitations on the present invention.

[0017] In the accompanying drawings of the instruction manual:

[0018] Figure 1 This is a schematic diagram of the device described in a specific embodiment;

[0019] Figure 2 A schematic diagram of the dust removal tower described in the specific implementation method;

[0020] Figure 3 This is a schematic diagram of the dechlorination tower described in a specific implementation method;

[0021] Figure 4 This is a schematic diagram of the hydrolysis tower described in the specific implementation method;

[0022] Figure 5 This is a schematic diagram of the desulfurization tower described in a specific embodiment. The reference numerals in the above figures are explained as follows: 1. Dust removal component;

[0023] 11. Dust removal tower;

[0024] 12. First feed pipe;

[0025] 13. First discharge pipe;

[0026] 14. First pressure gauge;

[0027] 15. Second pressure gauge;

[0028] 16. First dust removal layer;

[0029] 17. Second dust removal layer;

[0030] 18. Third dust removal layer;

[0031] 2. Dechlorination components;

[0032] 21. Dechlorination tower;

[0033] 22. Second feed pipe;

[0034] 23. Second discharge pipe;

[0035] 24. Reaction packing material;

[0036] 25. Protective packing material;

[0037] 3. Hydrolysis components;

[0038] 31. Hydrolysis tower;

[0039] 32. Third feed pipe;

[0040] 33. Third discharge pipe;

[0041] 34. Honeycomb ceramic structure;

[0042] 35. Heater;

[0043] 4. Desulfurization components;

[0044] 41. Desulfurization tower;

[0045] 411. First desulfurization zone;

[0046] 412. Second desulfurization zone;

[0047] 42. Fourth feed pipe;

[0048] 43. Fourth discharge pipe;

[0049] 44. Demister. Detailed Implementation

[0050] To illustrate in detail the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this utility model, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this utility model and are therefore intended to limit the scope of protection of this utility model.

[0051] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this utility model. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this utility model, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0052] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit the invention.

[0053] In the description of this utility model, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " generally indicates that the preceding and following objects have an "or" logical relationship.

[0054] In this invention, terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy, or order between these entities or operations.

[0055] Without further limitations, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this invention is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a series of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.

[0056] Similar to the understanding in the Examination Guidelines, in this utility model, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments of this utility model, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.

[0057] In the description of the embodiments of this utility model, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the convenience of describing the specific embodiments of this utility model or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model.

[0058] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this utility model, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this utility model pertains, the specific meaning of the above terms in the embodiments of this utility model can be understood according to the specific circumstances.

[0059] Please see Figures 1 to 5This embodiment provides a cascade dry gas dust removal, dechlorination, and desulfurization device, including a dust removal component 1, a dechlorination component 2, a hydrolysis component 3, and a desulfurization component 4. The dust removal component 1 includes a dust removal tower 11, a first feed pipe 12, and a first discharge pipe 13. The dust removal tower 11 is connected to the first feed pipe 12 and the first discharge pipe 13, respectively. The dust removal tower 11 is equipped with dust removal packing material, which is configured as metal fiber sintered felt, nano-ceramic fiber membrane, and oleophobic and hydrophobic coating. The dechlorination component 2 includes a dechlorination tower 21, a second feed pipe 22, and a second discharge pipe 23, respectively. The dechlorination tower 21 is connected to the second feed pipe 22 and the second discharge pipe 23, respectively. The second feed pipe 22 is connected to the first discharge pipe 12 and the first discharge pipe 13, respectively. The dechlorination tower 21 is equipped with dechlorination packing; the hydrolysis assembly 3 includes a heater 35, a hydrolysis tower 31, a third feed pipe 32, and a third discharge pipe 33. The input end of the heater 35 is connected to the second discharge pipe 23, and the output end of the heater 35 is connected to the third feed pipe 32. The hydrolysis tower 31 is connected to the third feed pipe 32 and the third discharge pipe 33 respectively. The hydrolysis tower 31 is equipped with hydrolysis packing; the desulfurization assembly 4 includes a desulfurization tower 41, a fourth feed pipe 42, and a fourth discharge pipe 43. The desulfurization tower 41 is connected to the fourth feed pipe 42 and the fourth discharge pipe 43 respectively. The third discharge pipe 33 is connected to the fourth feed pipe 42. The desulfurization tower 41 is equipped with desulfurization packing.

[0060] Dust collector tower 11 refers to a cylindrical pressure vessel, preferably made of corrosion-resistant stainless steel, used to house dust collector packing and complete the primary purification of coal gas. The metal fiber sintered felt in the dust collector packing is a three-dimensional network structure formed by high-temperature sintering of micron-sized metal fibers, used to intercept particles larger than 5μm; the nano-ceramic fiber membrane is a filter layer made of alumina nanofibers, used to capture submicron-sized dust; the oleophobic and hydrophobic coating is a fluoropolymer surface treatment layer used to prevent oil mist adhesion. The first feed pipe 12 and the first discharge pipe 13 are both flanged pipes, used for coal gas input and purified gas output, respectively.

[0061] The dechlorination tower 21 is a tower with a structure similar to the dust removal tower 11. The dechlorination packing material inside is preferably zinc oxide-copper oxide composite particles, which selectively remove chlorine-containing compounds such as HCl through chemical adsorption. The second feed pipe 22 and the first discharge pipe 13 are connected by socket welding to ensure airtightness. The heater 35 in the hydrolysis assembly 3 is used to heat the coal gas to the optimal temperature range for the hydrolysis reaction. The hydrolysis packing material inside the hydrolysis tower 31 is a titanium-based catalyst honeycomb structure, whose regular pore structure is conducive to airflow distribution and organic sulfur conversion. The desulfurization tower 41 has a collection hopper at the bottom, and its internal desulfurization packing material is iron oxide-zinc oxide composite particles, which fix H2S through chemical adsorption. The connecting pipes between the towers (the third feed pipe 32, the fourth feed pipe 42, etc.) are all designed with insulation to prevent temperature loss. Optionally, the first discharge pipe 13, the second discharge pipe 23, the third discharge pipe 33, and the fourth discharge pipe 43 are all equipped with pneumatic regulating valves to achieve precise flow control.

[0062] During operation, the coal gas enters the dust removal tower 11, where it undergoes tiered particulate filtration through a metal fiber sintered felt and a nano-ceramic fiber membrane. An oleophobic and hydrophobic coating ensures long-term, non-clogging operation. The pre-purified coal gas then enters the dechlorination tower 21 via the first discharge pipe 13. The active components in the dechlorination packing undergo an irreversible chemical reaction with chloride ions, fundamentally eliminating the risk of equipment corrosion. After dechlorination, the coal gas is heated by the heater 35 and then enters the hydrolysis tower 31, where organic sulfur compounds such as COS are converted to H2S under the action of a catalyst. Finally, the coal gas enters the desulfurization tower 41, where the desulfurization packing completely removes sulfides through chemical adsorption. The series design of this embodiment allows each purification unit to complement its function. The deep filtration of the dust removal packing creates clean conditions for subsequent processes, the high selectivity of the dechlorination packing protects the catalyst activity, and temperature-controlled hydrolysis ensures complete conversion of organic sulfur compounds, ultimately achieving efficient purification of all components of the coal gas. Compared to traditional processes, this device has significant advantages such as high purification efficiency, long operating cycle, and easy maintenance, making it particularly suitable for the deep treatment of complex gases such as blast furnace gas.

[0063] Please see Figure 2 In some embodiments, the dust removal tower 11 is provided with a first dust removal layer 16, a second dust removal layer 17 and a third dust removal layer 18 in sequence along the flow direction from the first feed pipe 12 to the first discharge pipe 13; the first dust removal layer 16 is configured as a metal fiber sintered felt; the second dust removal layer 17 is configured as a nano-ceramic fiber membrane; and the third dust removal layer 18 is configured as an oleophobic and hydrophobic coating.

[0064] The first dust removal layer 16 refers to the metal fiber sintered felt filter layer located at the airflow inlet. It adopts a multi-layered 316L stainless steel fiber felt structure, with a fiber diameter preferably of 8-12 μm and a porosity controlled at 60-70%. It is mainly used to intercept coarse dust particles larger than 10 μm in the gas. The second dust removal layer 17 refers to the nano-ceramic fiber membrane filter layer located in the middle section. This membrane layer is made of alumina nanofibers through a special process, with an average pore size of 0.5-1 μm, which can effectively capture fine particles of 1-10 μm. The third dust removal layer 18 refers to the oleophobic and hydrophobic coating functional layer near the gas outlet. This coating is formed on the surface of the metal substrate using plasma spraying technology to form a fluoropolymer film with a contact angle greater than 150°, which can effectively block the adhesion of oil mist and water vapor. The three-layer filtration structure is arranged in a gradient along the airflow direction. The first dust removal layer 16, with its sintered metal fiber felt, removes most of the dust load. The second dust removal layer 17, with its nano-ceramic fiber membrane, performs fine filtration. The third dust removal layer 18, with its oleophobic and hydrophobic coating, ensures that the filtration system will not clog during long-term operation. This guarantees dust removal efficiency and significantly extends service life.

[0065] Please see Figure 1 In some embodiments, the dust removal assembly 1 further includes a dust concentration sensor, a first pressure gauge 14 and a second pressure gauge 15. The dust concentration sensor is disposed in the first discharge pipe 13; the first pressure gauge 14 is disposed in the first feed pipe 12; and the second pressure gauge 15 is disposed in the first discharge pipe 13.

[0066] In this embodiment, the dust concentration sensor can be an online monitoring device based on the laser scattering principle, installed on the straight section of the first discharge pipe 13, for real-time detection of the residual particulate matter content in the gas after dust removal treatment. Preferably, its measurement range is 0-50 mg / m³. 3 The detection accuracy can reach ±1mg / m 3 The first pressure gauge 14 refers to the corrosion-resistant diaphragm pressure gauge installed on the first feed pipe 12 at the inlet end of the dust collector 11. It is used to monitor the input pressure of the raw coal gas, and its range is configured according to the system working pressure, with a typical value of 0-1.6 MPa. The second pressure gauge 15 refers to the same type of pressure gauge installed on the first discharge pipe 13 at the outlet end of the dust collector 11. It is used in conjunction with the first pressure gauge 14 to calculate the pressure loss of the dust collection section. These three measuring instruments are connected to the control system through a 4-20mA signal line, forming a complete dust collection efficiency monitoring system. The dust concentration sensor directly reflects the dust collection effect, while the pressure difference data of the pressure gauges before and after the dust collection is used to determine the degree of blockage of the dust collection packing, providing a basis for maintenance. This achieves comprehensive monitoring of the operating status of the dust collection component 1, ensuring that the purification quality meets the standards and providing timely warnings of filter material failure.

[0067] Please see Figure 3In some embodiments, the dechlorination packing is configured as a reaction packing 24 and a protective packing 25; the reaction packing 24 is configured as γ-Al2O3 spheres loaded with CuO / ZnO; and the protective packing 25 is configured as alkali-impregnated activated carbon.

[0068] In this embodiment, the reaction packing 24 refers to γ-Al2O3 carrier spheres with a diameter of 3-5 mm. Its surface is loaded with 20-30 wt% CuO / ZnO composite active components via impregnation. The specially formulated metal oxides exhibit selective chemical adsorption of chlorine-containing compounds such as HCl, and can fix chlorine as metal chlorides at an operating temperature of 200-300℃. The protective packing 25 refers to an alkali-impregnated activated carbon layer stacked on top of the reaction packing 24. It uses coconut shell activated carbon with a particle size of 4-6 mm as a carrier and, after impregnation with K2CO3 solution, has an alkali loading of 30-40%. It is mainly used to adsorb acidic gases and some heavy metal impurities in the coal gas, preventing them from poisoning the downstream reaction packing 24. These two packings are layered in a 2:1 volume ratio. The protective packing 25 is located upstream of the gas flow for pretreatment of the coal gas, while the reaction packing 24 performs deep dechlorination downstream. This combined design extends the overall service life of the packing material and ensures dechlorination efficiency through staged purification. The protective packing material 25 can be replaced periodically, while the reaction packing material 24 maintains a longer catalytic activity cycle. Porous distribution plates are installed between the packing layers to ensure uniform airflow through each reaction zone, preventing channeling phenomena that could affect the purification effect.

[0069] In some embodiments, the inner side of the dechlorination tower 21 is coated with a nickel-based alloy C276. Nickel-based alloy C276 refers to a corrosion-resistant alloy containing molybdenum, chromium, and tungsten (UNS N10276), which forms a continuous protective layer on the inner surface of the tower body through a high-pressure thermal spraying process. The coating process includes three stages: surface sandblasting pretreatment, coating application, and high-temperature post-treatment. Sandblasting is used to obtain an activated surface with Sa3 cleanliness, while high-temperature post-treatment is used to reduce coating porosity and enhance bonding strength. The coating is preferably positioned to cover the entire gas-phase contact area of ​​the dechlorination tower 21, including the cylinder section, the head transition zone, and the connection points of internal support components. In the packing filling area, the coating thickness needs to be adaptively increased to resist mechanical wear of the packing.

[0070] This embodiment utilizes a nickel-based alloy C276 coating to provide long-term protection for the dechlorination tower 21 in a chlorine-containing corrosive environment. When chlorine-containing gas flows through the tower, the molybdenum and chromium elements in the coating preferentially react with the corrosive medium to form a stable passivation film, blocking corrosion pathways in the base steel. Simultaneously, the dense structure of the coating prevents pitting corrosion caused by chloride ion penetration, and its high-temperature stability ensures continuous protection under fluctuating process temperatures. This maintains the overall pressure-bearing strength of the equipment and avoids the problem of easy aging of rubber or plastic linings.

[0071] In some embodiments, the heater 35 is configured as a brazed plate heat exchanger; the dechlorination assembly 2 also includes a heat pipe connected to the outside of the dechlorination tower 21, and the other end of the heat pipe is connected to the heater 35.

[0072] In this embodiment, the brazed plate heat exchanger uses a vacuum brazing process to integrally form stainless steel plates and copper-based brazing filler metal. Its corrugated plate structure creates staggered flow channels to enhance heat transfer. The heat transfer pipe is a seamless stainless steel pipe with an insulating outer wall. It is connected to the jacket cavity outside the dechlorination tower 21 via a flange connection, and its other end is welded to the heat medium outlet of the brazed plate heat exchanger, forming a closed-loop circulation circuit. The heat source for the heater 35 can be steam or thermal oil; saturated steam is preferred as the heating medium to utilize its latent heat of phase change and improve energy efficiency. The heat transfer pipe is arranged in a spiral coil structure on the dechlorination tower 21 side. This increases the contact area to ensure uniform temperature distribution within the tower. The pipe diameter must be selected to match the flow characteristics of the heat exchanger to avoid excessive flow resistance.

[0073] This embodiment achieves efficient thermal energy management of the dechlorination system through a brazed plate heat exchanger and heat pipes. The compact structure of the brazed plate heat exchanger reduces the floor space, and its high heat transfer coefficient ensures rapid response to process temperature regulation requirements, while the insulating design of the heat pipes effectively reduces heat loss during transport.

[0074] Please see Figure 4 In some embodiments, the hydrolysis packing is configured as a titanium-based catalyst; the hydrolysis tower 31 is provided with a honeycomb ceramic structure 34, and the hydrolysis packing is disposed within the honeycomb ceramic structure 34.

[0075] Titanium-based catalysts refer to composite catalytic materials that use porous titanium as a support and load active components. Their surfaces are oxidized to form catalytically active TiO2 crystals. The honeycomb ceramic structure 34 is an integral porous support made of cordierite or mullite, with a hexagonal grid-like cross-section. The inner walls of individual pores are coated with a γ-Al2O3 transition layer to enhance catalyst adhesion. Hydrolysis filler is extruded into the interconnected pores of the honeycomb ceramic, with a packing density controlled at 60%-70% to balance gas flow and catalytic contact area. The active component of the titanium-based catalyst is preferably a tungstate composite, which effectively promotes the hydrolysis of organochlorides at 120-180℃. The axial length to tower diameter ratio of the honeycomb ceramic structure 34 is 1:1.2 to 1:1.5 to ensure sufficient gas diffusion.

[0076] This embodiment significantly improves the dechlorination efficiency and operational stability of the hydrolysis tower 31 through the combined design of a titanium-based catalyst and a honeycomb ceramic structure 34. When the gas stream containing organic chlorides flows through the honeycomb ceramic channels, the titanium-based catalyst provides a large number of active sites that promote the breaking of C-Cl bonds, while the regular flow channels of the honeycomb ceramic effectively reduce gas pressure loss. The high thermal stability of the ceramic matrix avoids the local hot spot problem that is prone to occur in traditional random packed beds, and its integral structure also prevents the catalyst particles from pulverizing and being lost during long-term operation. The mesoporous characteristics of the titanium-based catalyst surface increase the reaction contact interface, while the isothermal distribution characteristics of the honeycomb ceramic ensure the uniformity of the reaction temperature throughout the tower. This enables the hydrolysis tower 31 to achieve efficient conversion of organic chlorine to inorganic chlorine with lower energy consumption and creates favorable conditions for the deep purification of the subsequent dechlorination tower 21. The overall system exhibits stronger adaptability to fluctuations in gas composition.

[0077] Please see Figure 5 In some embodiments, the desulfurization tower 41 includes a first desulfurization zone 411 and a second desulfurization zone 412, and the desulfurization packing includes a first desulfurization packing and a second desulfurization packing; the first desulfurization zone 411 is filled with the first desulfurization packing, and the second desulfurization zone 412 is filled with the second desulfurization packing; the input end of the first desulfurization zone 411 is connected to the fourth feed pipe 42, the output end of the first desulfurization zone 411 is connected to the input end of the second desulfurization zone 412, and the output end of the second desulfurization zone 412 is connected to the fourth discharge pipe 43.

[0078] The first desulfurization packing refers to a desulfurizing agent with iron oxide as the main active ingredient. Its particle diameter is 3-5 mm, possessing high sulfur capacity and mechanical strength, suitable for treating high-concentration hydrogen sulfide gas. The second desulfurization packing refers to a refined desulfurizing agent with zinc oxide as the main component. Its particle diameter is 1-2 mm, possessing a finer pore structure, specifically designed for deep removal of residual trace sulfides. The fourth feed pipe 42 is a 316L stainless steel pipe connecting to the output end of the hydrolysis tower 31, with a pipe diameter determined according to the design gas velocity (DN200-DN250). The fourth discharge pipe 43 is a 304 stainless steel pipe supplying purified gas to the downstream process, and is equipped with an interface for an online sulfur content analyzer. Optionally, a guide cone section is used between the first desulfurization zone 411 and the second desulfurization zone 412 to achieve uniform redistribution of airflow. The preferred inclination angle of the cone section is 60° to avoid ash accumulation.

[0079] This embodiment achieves efficient, stepwise removal of sulfides from coal gas through a staged desulfurization process. When sulfur-containing coal gas enters the first desulfurization zone 411 via the fourth feed pipe 42, the iron oxide packing preferentially reacts with high-concentration hydrogen sulfide to generate iron sulfide, completing the coarse desulfurization process. Subsequently, after adjusting the flow pattern in the guide section, the gas enters the second desulfurization zone 412, where zinc oxide packing removes residual organic sulfur and trace amounts of hydrogen sulfide through chemical adsorption. The dual-stage series structure fully utilizes the advantages of different desulfurization materials. The large-particle packing in the first desulfurization zone 411 ensures processing capacity and anti-clogging ability, while the small-particle packing in the second desulfurization zone 412 provides the final purification guarantee.

[0080] In some embodiments, the first desulfurization filler is configured as an iron oxide desulfurizer; the second desulfurization filler is configured as a nano-ZnO desulfurizer.

[0081] The first desulfurization packing material is an iron oxide desulfurizing agent, specifically using α-Fe₂O₃·H₂O as the main active component. Its particles are reddish-brown spherical, with a diameter of 3-5 mm and a bulk density of 0.8-1.0 g / cm³. 3 Specific surface area 60-80m² 2 / g, working sulfur capacity ≥30wt%. The second desulfurization filler is a nano-ZnO desulfurizer, which uses porous alumina as a carrier, with ZnO particles of 20-30nm on the surface, ZnO loading of 40-50wt%, particle diameter of 1-2mm, and bulk density of 1.2-1.4g / cm³. 3 Specific surface area 200-250m² 2 / g, breakthrough sulfur capacity ≥15wt%.

[0082] Iron oxide desulfurizer is suitable for high sulfur load conditions in the first desulfurization zone. It reacts with H2S at room temperature as follows:

[0083] Fe2O3·H2O+3H2S→2FeS+S+4H2O;

[0084] This reaction is exothermic; maintaining the optimal reaction kinetics by keeping the temperature in the first desulfurization zone between 30-50℃ is crucial. The nano-ZnO desulfurizing agent achieves deep desulfurization in the second desulfurization zone, and its reaction mechanism is as follows:

[0085] ZnO + H₂S → ZnS + H₂O;

[0086] The high specific surface area and quantum effect of nano-sized ZnO enable it to maintain excellent adsorption activity for ppm-level sulfides, and the reaction temperature should be controlled at 40-60℃.

[0087] In some embodiments, the output end of the second desulfurization zone 412 is further provided with a demister 44, the output end of which is connected to the fourth discharge pipe 43. The demister 44 is a gas-liquid separation device used to remove tiny droplets and solid particles entrained in the gas. Its structure can be a filter unit composed of multiple layers of metal wire mesh. The metal wire mesh is preferably made of 316L stainless steel to resist hydrogen sulfide corrosion. The surface of the wire mesh is hydrophobically treated to enhance the droplet capture capacity and prevent scaling and clogging.

[0088] This embodiment further purifies the gas before it is discharged by installing a demister 44 at the outlet of the second desulfurization zone 412. When the gas containing trace amounts of droplets and particulate matter passes through the demister 44, the wire mesh structure captures the suspended matter through inertial collision and interception. The dry and clean gas then enters the fourth discharge pipe 43 and is transported to the downstream process. This solves the problem of dust escape that may be generated by nano-level desulfurizing agents and also eliminates residual sulfide aerosols in the gas, ensuring that the cleanliness of the final output gas meets stringent process requirements. The demister 44 improves the terminal purification function of the desulfurization system, compensating for the limitations of chemical desulfurization in removing fine particulate matter through physical interception. The modular structure of the demister 44 facilitates maintenance and cleaning, and can be carried out simultaneously with the maintenance cycle of the desulfurization tower 41, without adding extra maintenance burden.

[0089] The above technical solution includes, in sequence, a dust removal component 1, a dechlorination component 2, a hydrolysis component 3, and a desulfurization component 4; the dust removal component 1 includes a dust removal tower 11, a first feed pipe 12, and a first discharge pipe 13, and the dust removal tower 11 is equipped with dust removal packing; the dechlorination component 2 includes a dechlorination tower 21, a second feed pipe 22, and a second discharge pipe 23, the second feed pipe 22 being connected to the first discharge pipe 13, and the dechlorination tower 21 being equipped with dechlorination packing; the hydrolysis component 3 includes a heater 35, a hydrolysis tower 31, a third feed pipe 32, and a third discharge pipe 33, the heater 35 being connected between the second discharge pipe 23 and the third feed pipe 32, and the hydrolysis tower 31 being equipped with hydrolysis packing; the desulfurization component 4 includes a desulfurization tower 41, a fourth feed pipe 42, and a fourth discharge pipe 43, the third discharge pipe 33 being connected to the fourth feed pipe 42, and the desulfurization tower 41 being equipped with desulfurization packing. Through a multi-stage series synergistic purification structure, efficient stepwise removal of dust, chloride ions and sulfides from coal gas is achieved. This not only solves the problems of catalyst poisoning and equipment corrosion in traditional processes, but also significantly improves the efficiency of hydrolysis reaction through heater 35, resulting in a significant improvement in operational stability and purification effect.

[0090] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this utility model, this should not limit the scope of patent protection of this utility model. Any technical solutions resulting from equivalent structural or procedural substitutions or modifications made based on the essential concept of this utility model and utilizing the content described in the text and drawings of this utility model, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of patent protection of this utility model.

Claims

1. A cascade dry gas dust removal, dechlorination, and desulfurization device, characterized in that, include: The dust removal assembly includes a dust removal tower, a first feed pipe, and a first discharge pipe. The dust removal tower is connected to the first feed pipe and the first discharge pipe respectively. The dust removal tower is provided with dust removal packing material, which is configured as metal fiber sintered felt, nano-ceramic fiber membrane, and oleophobic and hydrophobic coating. A dechlorination assembly includes a dechlorination tower, a second feed pipe, and a second discharge pipe. The dechlorination tower is connected to the second feed pipe and the second discharge pipe, respectively. The second feed pipe is connected to the first discharge pipe. The dechlorination tower is equipped with dechlorination packing. The hydrolysis assembly includes a heater, a hydrolysis tower, a third feed pipe, and a third discharge pipe. The input end of the heater is connected to the second discharge pipe, and the output end of the heater is connected to the third feed pipe. The hydrolysis tower is connected to the third feed pipe and the third discharge pipe, respectively. The hydrolysis tower is equipped with hydrolysis packing material. The desulfurization assembly includes a desulfurization tower, a fourth feed pipe, and a fourth discharge pipe. The desulfurization tower is connected to the fourth feed pipe and the fourth discharge pipe, respectively. The third discharge pipe is connected to the fourth feed pipe. The desulfurization tower is equipped with desulfurization packing.

2. The cascade dry gas dust removal, dechlorination, and desulfurization device according to claim 1, characterized in that, The dust removal tower is provided with a first dust removal layer, a second dust removal layer and a third dust removal layer in sequence from the first feed pipe to the first discharge pipe in the flow direction. The first dust removal layer is configured as a metal fiber sintered felt; The second dust removal layer is configured as a nano-ceramic fiber membrane; The third dust removal layer is configured as an oleophobic and hydrophobic coating.

3. The cascade dry gas dust removal, dechlorination, and desulfurization device according to claim 1, characterized in that, The dust removal assembly also includes: A dust concentration sensor is installed in the first discharge pipe; A first pressure gauge is installed in the first feed pipe; The second pressure gauge is installed in the first discharge pipe.

4. The cascade dry gas dust removal, dechlorination, and desulfurization device according to claim 1, characterized in that, The dechlorination packing is configured as both a reaction packing and a protective packing. The reaction filler is configured as γ-Al2O3 spheres loaded with CuO / ZnO; The protective filler is configured as alkali-impregnated activated carbon.

5. The cascade dry gas dust removal, dechlorination, and desulfurization device according to claim 1, characterized in that, The dechlorination tower has a nickel-based alloy C276 coating on its inner side.

6. The cascade dry gas dust removal, dechlorination, and desulfurization device according to claim 1, characterized in that, The heater is configured as a brazed plate heat exchanger. The dechlorination assembly also includes: A heat pipe is connected to the outside of the dechlorination tower, and the other end of the heat pipe is connected to the heater.

7. The cascade dry gas dust removal, dechlorination, and desulfurization device according to claim 1, characterized in that, The hydrolysis filler is configured as a titanium-based catalyst; The hydrolysis tower is equipped with a honeycomb ceramic structure, and the hydrolysis packing is disposed within the honeycomb ceramic structure.

8. The cascade dry gas dust removal, dechlorination, and desulfurization device according to claim 1, characterized in that, The desulfurization tower includes a first desulfurization zone and a second desulfurization zone, and the desulfurization packing includes a first desulfurization packing and a second desulfurization packing. The first desulfurization zone is filled with a first desulfurization packing material, and the second desulfurization zone is filled with a second desulfurization packing material. The input end of the first desulfurization zone is connected to the fourth feed pipe, the output end of the first desulfurization zone is connected to the input end of the second desulfurization zone, and the output end of the second desulfurization zone is connected to the fourth discharge pipe.

9. The cascade dry gas dust removal, dechlorination, and desulfurization device according to claim 8, characterized in that, The first desulfurization packing is configured as an iron oxide desulfurizing agent; The second desulfurization filler is configured as a nano-ZnO desulfurizer.

10. The cascade dry gas dust removal, dechlorination, and desulfurization device according to claim 9, characterized in that, The output end of the second desulfurization zone is also equipped with a demister, and the output end of the demister is connected to the fourth discharge pipe.

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