A combined device and method for desulfurization and decarburization and online blockage cleaning of blast furnace gas

Abstract

The application provides a combined device and method for desulfurization and decarburization of blast furnace gas and online blockage removal, which comprises a heat exchange temperature control unit, a desulfurization purification unit and a decarburization regeneration unit connected in sequence from front to back; the desulfurization purification unit comprises a dechlorination pretreatment reaction tower, a hydrolysis reaction tower and an adsorption reaction tower connected in sequence from front to back, and the three towers are respectively radial flushing reaction towers; a discharge port of the decarburization and regeneration unit is connected with a feed port of a liquid carbon dioxide preparation unit, a discharge port of the liquid carbon dioxide preparation unit is connected with a feed port of a dry ice preparation storage and distribution unit; a discharge port of the dry ice preparation storage and distribution unit is connected with a flushing port of the heat exchange temperature control unit; and the discharge port of the dry ice preparation storage and distribution unit is also connected with outer hole cylinder flushing ports and inner hole cylinder flushing ports of the dechlorination pretreatment reaction tower, the hydrolysis reaction tower and the adsorption reaction tower respectively. The device in the application realizes the carbon emission reduction target and the carbon dioxide resource utilization.

Description

Technical Field

[0001] This invention belongs to the field of energy conservation and environmental protection technology, and relates to equipment and methods for reducing pollution and carbon emissions from blast furnace gas, specifically to a combined device and method for desulfurization, decarbonization and online unblocking of blast furnace gas. Background Technology

[0002] The typical dry blast furnace gas has the following main components: CO: 24.0–26.0%, CO2: 20.0–24.0%, H2: 2.0–3.0%, N2: 49.0–53.0%, and O2: 0.0–1.5%. Impurities and pollutants in the blast furnace gas after dust removal mainly include tar, dust, salt, organic sulfur (mainly COS), inorganic sulfur (mainly H2S), and hydrogen chloride. The content of these impurities and pollutants is generally around 500 mg / Nm³. 3 Within this range. As the largest by-product gas of steel enterprises, the desulfurization and decarbonization of blast furnace gas is of paramount importance.

[0003] Currently, the low-temperature hydrolysis conversion and dry adsorption catalytic oxidation desulfurization technology for blast furnace gas after TRT (Transient Refrigerant Regulator) has matured, and multiple units have been built and are in operation. However, during operation, dust, tar, and crystalline salts in the gas frequently clog the orifice plates of the radial flushing reaction tower and the tube bundles of the heat exchanger. Commonly used industrial methods such as steam purging are not suitable for blast furnace gas desulfurization and purification units. Currently, offline flushing and cleaning are mainly relied upon, lacking effective online unclogging methods, which affects the stable operation of the unit. Therefore, there is an urgent need for a device and method that integrates desulfurization, decarbonization, and online unclogging functions to solve the above problems.

[0004] The method for decarbonization and fine desulfurization of blast furnace gas disclosed in patent CN116478739A adopts a process route of first decarbonizing and then desulfurizing. Acidic impurities such as chlorides and sulfides in the gas will contaminate the absorbent liquid, resulting in a decrease in absorption efficiency. This has a significant adverse effect on the amine method for removing carbon dioxide. This process route has drawbacks in its process design, and the process is complex and requires repeated adjustment of the gas temperature, resulting in high energy consumption and large equipment investment.

[0005] The desulfurization and decarbonization system and process for blast furnace gas disclosed in patent CN115558529A utilizes an absorbent to remove both H2S and carbon dioxide simultaneously. However, the subsequent desorption of the absorbent and the separation of sulfur are quite complex, resulting in a long overall process, a complex system, and high maintenance difficulty. Furthermore, it involves multiple heating and cooling operations and condensation gas-liquid separation operations, leading to high energy consumption.

[0006] Patent CN113684068A discloses a CO2 capture and utilization device suitable for blast furnace gas, which uses limestone before decarbonization. Gypsum wet coarse desulfurization uses alkaline spray for fine desulfurization. However, because the carbon dioxide content in the coal gas is much greater than the H2S content, some carbon dioxide will be absorbed by the alkaline solution during the alkaline spray desulfurization process. This weakens the selectivity of the absorbent for H2S, increases solvent consumption, and wastes the alkaline solution. This method has been proven to be ineffective in the past blast furnace gas desulfurization and is now rarely used. Summary of the Invention

[0007] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a combined device and method for desulfurization and decarbonization of blast furnace gas and online cleaning of blockage, so as to solve the technical problem that it is difficult to achieve both desulfurization and decarbonization of blast furnace gas and online cleaning of the device in the existing technology.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0009] A combined device for desulfurization, decarbonization, and online unblocking of blast furnace gas includes a heat exchange and temperature control unit. The outlet of the heat exchange and temperature control unit is connected to the inlet of the desulfurization and purification unit, and the outlet of the desulfurization and purification unit is connected to the inlet of the decarbonization and regeneration unit.

[0010] The desulfurization and purification unit includes a dechlorination pretreatment reaction tower, a hydrolysis reaction tower, and an adsorption reaction tower that are connected in sequence from front to back.

[0011] The dechlorination pretreatment reaction tower, hydrolysis reaction tower and adsorption reaction tower are all radial flushing reaction towers.

[0012] The outlet of the decarbonization and regeneration unit is connected to the inlet of the liquid carbon dioxide preparation unit, and the outlet of the liquid carbon dioxide preparation unit is connected to the inlet of the dry ice preparation, storage and distribution unit.

[0013] The outlet of the dry ice preparation, storage and distribution unit is also connected to the flushing port of the heat exchange and temperature control unit.

[0014] The outlet of the dry ice preparation, storage and distribution unit is also connected to the flushing port of the outer cylinder of the dechlorination pretreatment reaction tower, the hydrolysis reaction tower and the adsorption reaction tower.

[0015] The outlet of the dry ice preparation, storage and distribution unit is also connected to the flushing port of the inner cylinder of the dechlorination pretreatment reaction tower, the hydrolysis reaction tower and the adsorption reaction tower.

[0016] The present invention also has the following technical features: Specifically, the radial flushing reaction tower includes a closed radial flushing reaction tower shell, the internal cavity of the radial flushing reaction tower shell is an installation cavity, a bottom plate is horizontally arranged near the bottom of the installation cavity, and the outer side wall of the bottom plate is fixedly connected to the inner side wall of the radial flushing reaction tower shell along the circumference; the installation cavity at the upper part of the bottom plate is the upper axial section installation cavity, and the installation cavity at the lower part of the bottom plate is the lower axial section installation cavity.

[0017] The upper axial section of the mounting cavity is coaxially fitted with a cylindrical outer tube that is open at both ends in the axial direction. The upper axial end of the outer tube is fixedly connected to the top inner wall of the radial flushing reaction tower shell, and the lower axial end of the outer tube is fixedly connected to the upper part of the base plate. Inside the outer tube, a cylindrical inner tube that is open at both ends in the axial direction is also coaxially fitted. The upper axial end of the inner tube is fixedly connected to the top inner wall of the radial flushing reaction tower shell, and the lower axial end of the inner tube is fixedly connected to the upper part of the base plate.

[0018] The radial flushing reaction tower shell is also provided with multiple external cylinder flushing ports, which are evenly distributed circumferentially on the upper part of the bottom plate.

[0019] The axial upper section of the mounting cavity is also provided with multiple external orifice flushing pipes. The multiple external orifice flushing pipes are evenly distributed circumferentially between the inner side wall of the radial flushing reaction tower shell and the outer side wall of the external orifice. Each external orifice flushing pipe is arranged axially and is connected to the external orifice flushing port through a first inlet hose.

[0020] Each outer bore flushing pipe is provided with multiple radially penetrating outer bore nozzles on the side near the outer bore. The multiple outer bore nozzles are evenly distributed along the axial direction, and an outer bore nozzle is installed at each outer bore nozzle.

[0021] The radial flushing reaction tower shell is also provided with an inner tube flushing port, which is located at the upper axial end of the inner tube.

[0022] The axial upper section of the mounting cavity is also provided with an inner bore flushing pipe along the axial direction. The inner bore flushing pipe is coaxially fitted inside the inner bore, and the axial upper end of the inner bore flushing pipe is connected to the inner bore flushing port through a second inlet hose.

[0023] The inner bore flushing pipe is also provided with multiple inner bore nozzles that penetrate the sidewalls radially. The multiple inner bore nozzles are evenly distributed along the axial direction, and an inner bore nozzle is installed at each inner bore nozzle.

[0024] Specifically, the axial ends of the external tube flushing pipe are closed, and a buffer spring is provided at the lower axial end of the external tube flushing pipe. The lower axial end of the buffer spring is fixedly connected to the upper part of the base plate. A buffer spring is provided at the upper axial end of the external tube flushing pipe. The upper axial end of the buffer spring is fixedly connected to the inner wall of the radial flushing reaction tower shell.

[0025] The radial flushing reaction tower shell is also equipped with multiple axial reciprocating components on its side wall, which enable the outer tube flushing pipe to move up and down axially.

[0026] The inner wall of the radial flushing reaction tower shell is also equipped with multiple outer tube support guides. The multiple outer tube support guides are evenly distributed along the axial and circumferential directions. Each outer tube support guide is connected to the outer tube flushing pipe. The multiple outer tube support guides can support and guide the outer tube flushing pipe when it moves up and down along the axial direction.

[0027] The radial flushing reaction tower shell is also equipped with a drive motor. The output shaft of the drive motor is coaxially arranged with the inner cylinder flushing pipe. The inner cylinder flushing pipe can be driven by the output shaft of the drive motor to achieve circumferential rotation around its own central axis.

[0028] The inner wall of the inner cylinder is also equipped with multiple inner tube support guides. These multiple inner tube support guides are evenly distributed along the axial direction and can support and guide the inner cylinder flushing pipe when it rotates in the circumferential direction.

[0029] Specifically, the cavity between the inner wall of the outer bore and the outer wall of the inner bore is a filler cavity, which is filled with filler.

[0030] The outer cylinder is also provided with multiple radially penetrating gas channels on its sidewall, and the multiple gas channels are evenly distributed along the axial and circumferential directions respectively.

[0031] The inner cylinder is also provided with multiple radially penetrating gas channels on its sidewall, and the multiple gas channels are evenly distributed along the axial and circumferential directions respectively.

[0032] The radial flushing reaction tower shell is provided with a first reaction gas channel at its lower axial end and a second reaction gas channel at its upper axial end; the bottom plate is also provided with multiple third reaction gas channels, which are arranged between the outer cylinder and the radial flushing reaction tower shell.

[0033] The output shaft of the drive motor is also coaxially fitted with a protective sleeve, which is located inside the mounting cavity in the lower axial section.

[0034] The base plate is also equipped with a seal, which is located at the connection between the output shaft of the drive motor and the inner cylinder flushing pipe.

[0035] A swivel joint is also installed at the connection between the inner tube flushing pipe and the second inlet hose.

[0036] Specifically, the feed inlet of the heat exchange and temperature control unit is connected to the blast furnace gas transmission pipeline.

[0037] The heat exchange and temperature control unit includes a heat exchanger. The heat exchanger includes one or more combinations of a GGH heat exchanger, a heater, and a cooler.

[0038] The first channel of the dechlorination pretreatment reaction tower is connected to the outlet of the heat exchange and temperature control unit; the dechlorination pretreatment reaction tower contains a calcium-based or alumina-based dechlorinating agent to adsorb hydrogen chloride impurities in the coal gas to remove Cl. - The hydrolysis reaction tower contains a built-in γ-Al2O3-based hydrolysant to convert organic sulfur into inorganic sulfur; the adsorption reaction tower contains a built-in iron oxide-based or activated carbon-based adsorbent to remove inorganic sulfur, thereby achieving desulfurization and purification of the coal gas and obtaining clean coal gas after desulfurization and purification.

[0039] The decarbonization and regeneration unit includes an absorption tower. The inlet of the absorption tower is connected to the second channel of the reaction gas of the adsorption reaction tower. The outlet of the absorption tower is connected to the inlet of the auxiliary equipment of the absorption tower and desorption tower. The outlet of the auxiliary equipment of the absorption tower and desorption tower is connected to the inlet of the desorption tower. The outlet of the desorption tower is connected to the inlet of the liquid carbon dioxide preparation unit.

[0040] The absorption tower and desorption tower auxiliary equipment include one or more combinations of cooling tower, lean and rich liquid heat exchanger and washing tower.

[0041] The liquid carbon dioxide preparation unit includes one or more combinations of a compressor, an ice machine, a precooler, a distillation column, a condenser, a subcooler, and a product storage tank.

[0042] The dry ice preparation, storage and distribution unit includes one or more combinations of an expansion chamber, a dry ice pellet mill, a dry ice insulation box and conveying equipment and pipelines.

[0043] This invention also protects a combined method for blast furnace gas desulfurization, decarbonization, and online unblocking, which is implemented using the combined blast furnace gas desulfurization, decarbonization, and online unblocking device described above; the method specifically includes the following steps: Step 1, Adjust the temperature: Using the GGH heat exchanger in the heat exchange and temperature control unit, the media on both sides of the GGH heat exchanger are blast furnace gas and desulfurized purified gas, respectively. The temperature of the blast furnace gas is adjusted to 60℃~90℃ to obtain gas with regulated temperature.

[0044] Step 2, Desulfurization: The coal gas obtained in step one after temperature adjustment is fed into the dechlorination pretreatment reaction tower in the desulfurization and purification unit, and then passes through the hydrolysis reaction tower and the adsorption reaction tower to obtain the desulfurized and purified coal gas.

[0045] Step 3, decarbonization: The desulfurized and purified coal gas obtained in step two is introduced into the absorption tower of the decarbonization and regeneration unit. Using an alcohol amine solution or ammonia water as the absorbent, carbon dioxide in the desulfurized and purified coal gas is absorbed in the absorption tower by chemical absorption. The rich liquid after carbon dioxide absorption enters the desorption tower for desorption and regeneration to obtain regenerated carbon dioxide gas. The decarbonized purified coal gas is then output and stored for later use.

[0046] Step 4, liquefaction: The regenerated carbon dioxide gas obtained in step three is introduced into the liquid carbon dioxide preparation unit, and a liquefaction distillation process is used to produce industrial-grade or food-grade liquid carbon dioxide products from the regenerated carbon dioxide gas.

[0047] Step 5, online congestion clearing: A portion of the liquid carbon dioxide product obtained in step four is extracted and fed into the dry ice preparation, storage and distribution unit to form dry ice pellets, while the other portion is stored as liquid carbon dioxide product for later use. The dry ice pellets are then sprayed through the dry ice preparation, storage and distribution unit onto the orifice plate of the radial flushing reaction tower of the desulfurization purification unit, as well as the tube bundles of the heat exchanger in the heat exchange and temperature control unit, which are prone to clogging, to achieve online unclogging.

[0048] Specifically, in step one, the temperature of the blast furnace gas is adjusted from 30℃~60℃ or greater than or equal to 90℃ to 60℃~90℃ to obtain the gas with adjusted temperature.

[0049] Specifically, in step two, the Cl in the dechlorination pretreatment reaction tower... - The removal of H2S to ≤1mg / Nm³; the COS conversion rate during inorganic sulfur conversion in the hydrolysis reaction tower is ≥95%; the removal of H2S to ≤1mg / Nm³ during desulfurization and purification in the adsorption reaction tower.

[0050] Specifically, in step three, when absorbing carbon dioxide from the desulfurized and purified coal gas, the carbon dioxide absorption rate is ≥90%; when desorption and regeneration are carried out in the desorption tower, the regenerated carbon dioxide concentration is ≥95%.

[0051] Specifically, in step five, the dry ice particles have a particle size of 1–3 mm.

[0052] Compared with the prior art, the present invention has the following technical effects: (I) The device in this invention uses the byproduct of decarbonization regeneration, namely high-concentration carbon dioxide gas, to prepare liquid carbon dioxide products and dry ice products, thereby reducing carbon dioxide emissions, achieving carbon emission reduction targets and carbon dioxide resource utilization, generating additional economic benefits, and reducing the overall cost of blast furnace gas purification treatment; at the same time, dry ice products are used to clean the tube bundles of the heat exchanger and the orifice plates of the radial flushing reaction tower online, ensuring the continuity of production and achieving a balance between the economic and environmental benefits of the enterprise.

[0053] (II) The device in this invention achieves deep removal of sulfur and effective removal of carbon dioxide from blast furnace gas through combined desulfurization and decarbonization. It boasts high desulfurization efficiency, controlling the total sulfur content in blast furnace gas to an extremely low level, meeting the ultra-low emission requirements of the steel industry for gas purification, and providing clean energy for subsequent gas utilization. The total sulfur in the blast furnace gas is removed to below 10 mg / Nm³. Further decarbonization after desulfurization reduces the carbon dioxide content in the gas from 20-24% to 1-2%, significantly reducing carbon emissions and effectively improving purification efficiency.

[0054] (III) The device in this invention effectively solves the problem of equipment blockage by using dry ice for online cleaning. The device does not require offline cleaning, greatly improving operational stability, reducing frequent shutdowns and maintenance time and costs caused by blockages, extending the device's service life, and increasing production efficiency. The low-temperature embrittlement of deposits by dry ice particles improves cleaning efficiency and extends the desulfurization and purification unit's operating cycle by 3 to 5 times. It avoids production interruptions caused by offline cleaning, reducing annual maintenance costs by 50%.

[0055] (IV) The device in this invention can increase the calorific value of blast furnace gas. The combustible component in blast furnace gas is mainly CO, which accounts for more than 20%. After removing carbon dioxide, the CO concentration is even higher, and the calorific value of the blast furnace gas is even higher. The carbon dioxide absorption rate is ≥90%, and the calorific value of the blast furnace gas is increased by 5% to 8%.

[0056] (V) The device in this invention is simple and compact. The entire device integrates functions such as desulfurization, decarbonization, carbon dioxide product preparation, and online unblocking, optimizes the process flow, reduces the equipment footprint, and lowers investment costs and operating energy consumption. It has good feasibility and scalability.

[0057] (VI) The method in this invention solves the defects of existing blast furnace gas desulfurization and decarbonization technologies, such as complex processes, prominent equipment blockage problems, and limited removal effects. It realizes the deep purification and resource utilization of blast furnace gas, meets the needs of ultra-low emissions and carbon emission reduction in the steel industry, realizes the resource utilization of carbon dioxide, and forms a closed loop of pollution reduction and carbon reduction.

[0058] (VII) The method in this invention optimizes the desulfurization and decarbonization processes to ensure that while achieving efficient desulfurization, the decarbonization effect is also optimal, thereby improving the efficiency and quality of coal gas purification.

[0059] (VIII) The method in this invention uses dry ice for online unblocking, which effectively cleans clogged equipment and ensures the stable operation of the device. Attached Figure Description

[0060] Figure 1 This is a schematic diagram of the overall structure of the device of the present invention.

[0061] Figure 2 This is a schematic axial cross-sectional view of the radial flushing reaction tower in the device of the present invention.

[0062] Figure 3 This is a schematic cross-sectional view of the radial flushing reaction tower in the device of the present invention.

[0063] Figure 4(a) is a partially enlarged physical image of the outer cylinder in the device of the present invention in a clean state.

[0064] Figure 4(b) is a partially enlarged physical image of the outer cylinder in the device of the present invention when it is completely blocked.

[0065] Figure 5(a) is a physical image of the heat exchanger tube bundle in the device of the present invention in a clean state.

[0066] Figure 5(b) is a physical diagram of the heat exchanger tube bundle in the device of the present invention when it is severely fouled.

[0067] The meanings of the labels in the diagram are as follows: 1-Heat exchange and temperature control unit, 2-Desulfurization and purification unit, 3-Decarbonization and regeneration unit, 4-Liquid carbon dioxide preparation unit, 5-Dry ice preparation, storage and distribution unit, 6-Radial flushing reaction tower, 7-Packing.

[0068] 201 - Dechlorination pretreatment reaction tower, 202 - Hydrolysis reaction tower, 203 - Adsorption reaction tower.

[0069] 301 - Absorption tower, 302 - Absorption tower and desorption tower auxiliary equipment, 303 - Desorption tower.

[0070] 601-Radial flushing of the reaction tower shell, 602-Mounting cavity, 603-Base plate, 604-Outer bore, 605-Inner bore, 606-Outer bore flushing port, 607-Outer bore flushing pipe, 608-First inlet hose, 609-Outer bore nozzle, 610-Inner bore flushing port, 611-Inner bore flushing pipe, 612-Second inlet hose, 613-Inner bore nozzle, 614-Lower end buffer spring of outer tube, 615-Upper end buffer spring of outer tube, 616-Axial up and down Reciprocating assembly, 617-Outer tube support guide, 618-Drive motor, 619-Inner tube support guide, 620-Filling cavity, 621-Outer cylinder gas channel, 622-Inner cylinder gas channel, 623-First reaction gas channel, 624-Second reaction gas channel, 625-Third reaction gas channel, 626-Seal, 627-Rotating joint, 628-Outer cylinder nozzle, 629-Inner cylinder nozzle, 630-Protective sleeve, 631-Outer cylinder flushing pipe branch.

[0071] 60201 - Lower axial section mounting cavity, 60202 - Upper axial section mounting cavity.

[0072] The specific content of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0073] It should be noted that, unless otherwise specified, all equipment, components and materials in this invention are based on equipment, components and materials known in the prior art. For example, the absorption tower is a known absorption tower, the drive motor is a known drive motor, the compressor is a known compressor, the ice machine is a known ice machine, the precooler is a known precooler, the first inlet hose and the second inlet hose are both known hoses, the packing is a known packing, the calcium-based or alumina-based dechlorinating agent is a known calcium-based or alumina-based dechlorinating agent, the γ-Al2O3-based hydrolysant is a known γ-Al2O3-based hydrolysant, and the iron oxide-based or activated carbon-based adsorbent is a known iron oxide-based or activated carbon-based adsorbent.

[0074] The technical concept of this invention is as follows: The temperature of the gas after blast furnace dust removal and blast furnace gas residual pressure turbine generator is first adjusted, and then a "pretreatment + hydrolysis + dry adsorption desulfurization" technology is adopted. This solves many problems existing in traditional blast furnace gas desulfurization technologies, such as dispersed post-combustion emission points, high carbon dioxide concentration leading to large alkali consumption in traditional wet hydrogen sulfide removal processes, system wastewater discharge, equipment corrosion, complex reaction processes, difficulty in forming elemental sulfur, complex operation, decreased calorific value due to increased water content, and the need for a pressure boosting device due to high system resistance. Simultaneously, this technology, due to the inclusion of a pretreatment agent, protects the hydrolysis catalyst from the dual effects of high-temperature filter bag damage and excessive dust and impurities.

[0075] This technology has the following advantages: First, it possesses mature, stable, and reliable desulfurizing agents and hydrolysants with long-term operation. Extensive project verification has shown that, compared to existing catalysts with regeneration capabilities on the market, it offers higher reliability and stronger stability, avoiding problems such as low regeneration efficiency and short service life.

[0076] Secondly, the dechlorination pretreatment device can adapt to the complex operating conditions of blast furnaces, is simple and reliable, has low energy consumption and does not generate wastewater, effectively improving the problems of complex systems, high energy consumption and large amounts of wastewater generated by other fine desulfurization pretreatment devices.

[0077] Third, the core equipment such as the hydrolysis tower and desulfurization tower adopts an advanced radial fixed bed structure, which has the advantages of uniform flow field, low bed pressure drop, low equipment energy consumption, high space velocity, high processing capacity and easy large-scale production.

[0078] Fourth, adopting standardized and modular design concepts can significantly improve design efficiency, reduce construction difficulty, and save material costs.

[0079] Chemical absorption decarbonization technologies (including the alkanolamine method and the ammonia method) have been demonstrated and applied in industries such as power generation and coal chemical engineering for the removal of carbon dioxide from flue gas from coal-fired boilers. However, blast furnace gas decarbonization has not yet received significant attention. While blast furnace gas is already relatively clean after desulfurization, it can undergo further decarbonization treatment to thoroughly reduce pollution and carbon emissions. The high-concentration carbon dioxide gas regenerated after blast furnace gas decarbonization can be used to produce industrial or food-grade liquid carbon dioxide products and dry ice products. The resulting dry ice particles can be used for online cleaning of the orifice plates and heat exchanger tube bundles in radial flushing reaction towers, ensuring the long-term stable operation of the desulfurization and purification equipment.

[0080] Besides dry ice online cleaning systems, other online unblocking technologies such as ultrasonic unblocking, jet unblocking, or vibration unblocking can be considered. Ultrasonic unblocking uses the vibration of ultrasonic waves to loosen and remove blockages; jet unblocking uses a high-speed fluid jet to impact the blocked area and wash away the blockage; vibration unblocking uses mechanical vibration to cause relative displacement between equipment components and the blockage, thereby clearing the blockage. These methods each have their advantages and applicable scope, but considering factors such as equipment structure, the nature of the blockage, operating conditions, and equipment stability, none are currently suitable for online unblocking of blast furnace gas purification devices.

[0081] In this invention, the full name of the GGH heat exchanger is Gas-Gas Heater. The GGH heat exchanger refers to a gas-to-gas heat exchanger. The gas-to-gas heat exchanger adopts the commonly known gas-to-gas heat exchanger in the art. In this invention, the gas-to-gas heat exchanger is used for heat exchange between high-temperature coal gas and low-temperature coal gas.

[0082] In this invention, the perforated plate includes an outer perforated cylinder 604 and an inner perforated cylinder 605, and the perforated plate adopts a commonly used perforated plate known in the art.

[0083] The working principle of dry ice cleaning in this invention is as follows: when dry ice particles come into contact with the surface being cleaned, several key processes occur: First, the temperature effect: Because dry ice particles have an extremely low sublimation temperature (about -78.5℃), they quickly cool the dirt and coatings on the cleaned surface, causing the dirt and coatings to become brittle and shrink, making them easier to remove.

[0084] Second, the expansion effect: When dry ice particles come into contact with the surface being cleaned, the dry ice particles quickly sublimate into gaseous carbon dioxide, generating a gas impact that helps to blow away impurities on the surface being cleaned.

[0085] Third, impact effect: Dry ice particles have high-speed impact capabilities, which can break up dirt, coatings and deposits on the surface being cleaned.

[0086] Following the above technical solutions, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0087] Example 1: This embodiment presents a combined device for blast furnace gas desulfurization, decarbonization, and online unblocking, such as... Figure 1 As shown, it includes a heat exchange and temperature control unit 1, the outlet of which is connected to the inlet of the desulfurization and purification unit 2, and the outlet of the desulfurization and purification unit 2 is connected to the inlet of the decarbonization and regeneration unit 3.

[0088] The desulfurization and purification unit 2 includes a dechlorination pretreatment reaction tower 201, a hydrolysis reaction tower 202, and an adsorption reaction tower 203 connected in sequence from front to back.

[0089] The dechlorination pretreatment reaction tower 201, the hydrolysis reaction tower 202 and the adsorption reaction tower 203 are respectively equipped with radial flushing reaction tower 6.

[0090] The outlet of the decarbonization and regeneration unit 3 is connected to the inlet of the liquid carbon dioxide preparation unit 4, and the outlet of the liquid carbon dioxide preparation unit 4 is connected to the inlet of the dry ice preparation, storage and distribution unit 5.

[0091] The outlet of the dry ice preparation, storage and distribution unit 5 is also connected to the flushing port of the heat exchange and temperature control unit 1.

[0092] The outlet of the dry ice preparation, storage and distribution unit 5 is also connected to the outer tube flushing port 606 of the dechlorination pretreatment reaction tower 201, the hydrolysis reaction tower 202 and the adsorption reaction tower 203, respectively.

[0093] The outlet of the dry ice preparation, storage and distribution unit 5 is also connected to the inner tube flushing port 610 of the dechlorination pretreatment reaction tower 201, the hydrolysis reaction tower 202 and the adsorption reaction tower 203, respectively.

[0094] As a preferred embodiment of this invention, such as Figures 2 to 3 As shown, the radial flushing reaction tower 6 includes a closed radial flushing reaction tower shell 601. The internal cavity of the radial flushing reaction tower shell 601 is a mounting cavity 602. A base plate 603 is horizontally arranged near the bottom in the mounting cavity 602. The outer side wall of the base plate 603 is fixedly connected to the inner side wall of the radial flushing reaction tower shell 601 in the circumferential direction. The mounting cavity 602 at the upper part of the base plate 603 is the axial upper section mounting cavity 60202, and the mounting cavity 602 at the lower part of the base plate 603 is the axial lower section mounting cavity 60201.

[0095] A cylindrical outer bore 604 with open axial ends is coaxially fitted inside the axial upper section mounting cavity 60202. The upper axial end of the outer bore 604 is fixedly connected to the top inner wall of the radial flushing reaction tower shell 601, and the lower axial end of the outer bore 604 is fixedly connected to the upper part of the bottom plate 603. A cylindrical inner bore 605 with open axial ends is also coaxially fitted inside the outer bore 604. The upper axial end of the inner bore 605 is fixedly connected to the top inner wall of the radial flushing reaction tower shell 601, and the lower axial end of the inner bore 605 is fixedly connected to the upper part of the bottom plate 603.

[0096] The radial flushing reaction tower shell 601 is also provided with multiple external cylinder flushing ports 606, which are evenly distributed circumferentially on the upper part of the bottom plate 603.

[0097] Multiple external orifice flushing pipes 607 are also arranged in the axial upper section mounting cavity 60202. The multiple external orifice flushing pipes 607 are evenly arranged circumferentially between the inner side wall of the radial flushing reaction tower shell 601 and the outer side wall of the external orifice 604. Each external orifice flushing pipe 607 is arranged axially and each external orifice flushing pipe 607 is connected to the external orifice flushing port 606 through the first inlet hose 608.

[0098] Each outer bore flushing pipe 607 is provided with multiple radially penetrating outer bore nozzles 609 on the side near the outer bore 604. The multiple outer bore nozzles 609 are evenly distributed along the axial direction, and an outer bore nozzle 628 is installed at each outer bore nozzle 609.

[0099] The radial flushing reaction tower shell 601 is also provided with an inner tube flushing port 610, which is located at the upper axial end of the inner tube 605.

[0100] An inner bore flushing pipe 611 is also provided axially inside the upper section of the mounting cavity 60202. The inner bore flushing pipe 611 is coaxially fitted inside the inner bore 605. The upper axial end of the inner bore flushing pipe 611 is connected to the inner bore flushing port 610 through a second inlet hose 612.

[0101] The inner tube flushing pipe 611 is also provided with multiple inner tube nozzles 613 that penetrate the side wall radially. The multiple inner tube nozzles 613 are evenly distributed along the axial direction, and an inner tube nozzle 629 is installed at each inner tube nozzle 613.

[0102] In this embodiment, both the first inlet hose 608 and the second inlet hose 612 have sufficient expansion margin.

[0103] In this embodiment, two adjacent external cylinder flushing pipes 607 are connected by external cylinder flushing pipe branch pipes 631 arranged along an arc. The external cylinder flushing pipe branch pipes 631 and the first inlet hose 608 correspond one-to-one. An external cylinder flushing port 606 is connected to the first inlet hose 608 and the external cylinder flushing pipe branch pipe 631 in sequence, and finally connected to the two adjacent external cylinder flushing pipes 607 at the same time.

[0104] In this embodiment, the outer orifice nozzle 628 is a flushing nozzle with an angle of 60 to 150 degrees. Under normal operating conditions, a fan-shaped nozzle with a long, narrow flushing area is preferred; under better operating conditions, a conical nozzle with a circular flushing area can also be selected. In this embodiment, the outer orifice nozzle 628 selected is a fan-shaped nozzle. The fan-shaped nozzle adopts a commonly used fan-shaped nozzle known in the art.

[0105] In this embodiment, the inner tube nozzle 629 is also a fan-shaped nozzle.

[0106] In this embodiment, the axial direction of the radial flushing reaction tower shell 601 is vertical.

[0107] In this embodiment, dry ice particles are sprayed onto the orifice plate and heat exchanger tube bundle surface of the radial flushing reaction tower 6 through the outer orifice nozzle 628 and the inner orifice nozzle 629. The impact force and sublimation properties of the dry ice particles are utilized to remove blockages, achieving online unblocking. Impurities generated during cleaning are discharged with the gas flow, eliminating the need for shutdown maintenance.

[0108] As a preferred embodiment, the axial ends of the external tube flushing pipe 607 are closed, and the lower axial end of the external tube flushing pipe 607 is provided with a lower outer tube buffer spring 614, the lower axial end of the lower outer tube buffer spring 614 is fixedly connected to the upper part of the base plate 603; the upper axial end of the external tube flushing pipe 607 is provided with an upper outer tube buffer spring 615, the upper axial end of the upper outer tube buffer spring 615 is fixedly connected to the inner wall of the radial flushing reaction tower shell 601.

[0109] Multiple axial reciprocating components 616 are also installed on the side wall of the radial flushing reaction tower shell 601. The axial reciprocating components 616 enable the outer cylinder flushing pipe 607 to move up and down along the axial direction.

[0110] Multiple outer tube support guides 617 are also installed on the inner wall of the radial flushing reaction tower shell 601. The multiple outer tube support guides 617 are evenly distributed along the axial and circumferential directions. Each outer tube support guide 617 is connected to the outer tube flushing pipe 607. The multiple outer tube support guides 617 can support and guide the outer tube flushing pipe 607 when it moves up and down along the axial direction.

[0111] A drive motor 618 is also installed on the radial flushing reaction tower shell 601. The output shaft of the drive motor 618 is coaxially arranged with the inner cylinder flushing pipe 611. The inner cylinder flushing pipe 611 can be driven by the output shaft of the drive motor 618 to achieve circumferential rotation around its own central axis.

[0112] Multiple inner tube support guides 619 are also installed on the inner wall of the inner cylinder 605. The multiple inner tube support guides 619 are evenly distributed along the axial direction. The multiple inner tube support guides 619 can support and guide the inner cylinder flushing pipe 611 when it rotates in the circumferential direction.

[0113] In this embodiment, the axial up-and-down reciprocating component 616 is a motor-driven linear reciprocating motion mechanism, which adopts a motor-driven linear reciprocating motion mechanism commonly known in the art.

[0114] In this embodiment, the axial reciprocating assembly 616 and the outer bore flushing pipe branch 631 are in one-to-one correspondence. The axial reciprocating assembly 616 and the outer bore flushing pipe branch 631 are connected, that is, one axial reciprocating assembly 616 can drive two outer bore flushing pipes 607 at the same time.

[0115] In this embodiment, multiple outer tube support guides 617 enable the outer tube flushing pipe 607 and the outer tube nozzle 628 to move only up and down along the axial direction; the outer tube support guides 617 adopt commonly used outer tube support guides known in the art.

[0116] In this embodiment, the lower end buffer spring 614 and the upper end buffer spring 615 of the outer tube play a buffering role when the outer tube flushing pipe 607 moves up and down along the axial direction. At the same time, the lower end buffer spring 614 and the upper end buffer spring 615 of the outer tube can also be replaced by anti-collision blocks or buffer blocks.

[0117] In this embodiment, multiple inner tube support guides 619 enable the inner tube flushing pipe 611 to rotate only in the circumferential direction, and the central axis of the inner tube flushing pipe 611 during circumferential rotation is the central axis of the inner tube flushing pipe 611; the inner tube support guides 619 adopt the commonly known inner tube support guides 619 in the art.

[0118] In this embodiment, each inner tube support guide 619 is connected to the inner wall of the inner bore 605, with three connection points.

[0119] As a preferred embodiment, the cavity between the inner wall of the outer cylinder 604 and the outer wall of the inner cylinder 605 is a packing cavity 620, which is filled with packing 7.

[0120] Multiple radially penetrating gas channels 621 are provided on the side wall of the outer cylinder 604, and the multiple gas channels 621 are evenly distributed along the axial and circumferential directions respectively.

[0121] Multiple gas channels 622 that radially penetrate the sidewall of the inner cylinder 605 are also provided on the sidewall. The multiple gas channels 622 are evenly distributed along the axial and circumferential directions.

[0122] The radial flushing reaction tower shell 601 is provided with a first reaction gas channel 623 at the lower axial end and a second reaction gas channel 624 at the upper axial end. Multiple third reaction gas channels 625 are also provided on the bottom plate 603, and the multiple third reaction gas channels 625 are arranged between the outer cylinder 604 and the radial flushing reaction tower shell 601.

[0123] A protective sleeve 630 is also coaxially mounted on the output shaft of the drive motor 618, and the protective sleeve 630 is arranged inside the axial lower section mounting cavity 60201.

[0124] A seal 626 is also installed on the base plate 603. The seal 626 is located at the connection between the output shaft of the drive motor 618 and the inner tube flushing pipe 611.

[0125] A swivel joint 627 is also installed at the connection between the inner tube flushing pipe 611 and the second inlet hose 612.

[0126] As can be seen from Figures 4(a) to 5(b), dry ice particles have a good cleaning effect, which further ensures the continuity of production and realizes online unclogging of the device.

[0127] In this embodiment, the first reaction gas channel 623 is the reaction gas inlet, and the second reaction gas channel 624 is the reaction gas outlet. The reaction gas entering the dechlorination pretreatment reaction tower 201 refers to the blast furnace gas after its temperature has been adjusted by the heat exchange and temperature control unit 1, that is, the blast furnace gas with a temperature of 60-90°C.

[0128] In this embodiment, the rotary joint 627 ensures that the second inlet hose 612 remains stationary, while the inner tube flushing pipe 611 rotates around its own central axis. The rotary joint 627 is a commonly known rotary joint 627 in the art.

[0129] In this embodiment, the seal 626 ensures both the circumferential rotation of the inner cylinder flushing pipe 611 around its own axis and a reliable seal at the connection between the inner cylinder flushing pipe 611 and the output shaft of the drive motor 618 on the base plate 603. The seal 626 is a commonly used seal known in the art.

[0130] In this embodiment, the protective sleeve 630 ensures that the output shaft of the drive motor 618 does not come into contact with the reaction gas.

[0131] As a preferred embodiment, the feed inlet of the heat exchange and temperature control unit 1 is connected to the blast furnace gas transmission pipeline.

[0132] The heat exchange temperature control unit 1 includes a heat exchanger; the heat exchanger includes one or more combinations of a GGH heat exchanger, a heater, and a cooler.

[0133] The first reaction gas channel 623 of the dechlorination pretreatment reaction tower 201 is connected to the outlet of the heat exchange and temperature control unit 1; the dechlorination pretreatment reaction tower 201 contains a calcium-based or alumina-based dechlorinating agent to adsorb hydrogen chloride impurities in the coal gas to remove Cl. - The hydrolysis reaction tower 202 contains a built-in γ-Al2O3-based hydrolysant to convert organic sulfur into inorganic sulfur; the adsorption reaction tower 203 contains a built-in iron oxide-based or activated carbon-based adsorbent to remove inorganic sulfur, thereby achieving desulfurization and purification of the coal gas and obtaining clean coal gas after desulfurization and purification.

[0134] The decarbonization and regeneration unit 3 includes an absorption tower 301. The inlet of the absorption tower 301 is connected to the second reaction gas channel 624 of the adsorption reaction tower 203. The outlet of the absorption tower 301 is connected to the inlet of the auxiliary equipment 302 of the absorption tower and desorption tower. The outlet of the auxiliary equipment 302 of the absorption tower and desorption tower is connected to the inlet of the desorption tower 303. The outlet of the desorption tower 303 is connected to the inlet of the liquid carbon dioxide preparation unit 4.

[0135] The absorption tower and desorption tower auxiliary equipment 302 includes one or more combinations of cooling tower, lean and rich liquid heat exchanger and scrubbing tower.

[0136] The liquid carbon dioxide production unit 4 includes one or more combinations of a compressor, an ice machine, a precooler, a distillation column, a condenser, a subcooler, and a product storage tank.

[0137] The dry ice preparation, storage and distribution unit 5 includes one or more combinations of an expansion chamber, a dry ice pellet mill, a dry ice insulation box and conveying equipment and pipelines.

[0138] In this embodiment, the blast furnace gas transmission pipeline adopts the commonly used blast furnace gas transmission pipeline known in the art. The blast furnace gas is transported in the blast furnace gas transmission pipeline. The blast furnace gas is the blast furnace gas generated during the production and processing of steel enterprises, etc.

[0139] In this embodiment, the conveying equipment and pipelines used are those commonly known in the art.

[0140] In this embodiment, the heat exchange temperature control unit 1 is used to regulate the temperature of blast furnace gas. By adjusting the flow rate of steam or cooling medium, the temperature of blast furnace gas is controlled at 60-90°C, providing suitable temperature conditions for the subsequent desulfurization reaction.

[0141] In this embodiment, the dechlorination pretreatment reaction tower 201, the hydrolysis reaction tower 202, and the adsorption reaction tower 203 are all dechlorination pretreatment reaction towers, hydrolysis reaction towers, and adsorption reaction towers known in the art.

[0142] In this embodiment, the decarbonization and regeneration unit 3 achieves the purpose of decarbonization and carbon dioxide regeneration. The calorific value of the gas after carbon dioxide removal is increased, and it can be used as fuel for subsequent applications.

[0143] In this implementation, the liquid carbon dioxide preparation unit 4 is used to prepare industrial or food-grade liquid carbon dioxide products, thereby realizing the resource utilization of carbon dioxide.

[0144] In this implementation, dry ice particles are sprayed onto the orifice plate of the radial flushing reaction tower 6 in the desulfurization purification unit 2, and the tube bundles of the heat exchanger in the heat exchange and temperature control unit 1, as well as other easily clogged parts, through the dry ice preparation, storage, and distribution unit 5, pipelines, and nozzles. The low temperature and impact of the dry ice cause impurities such as dust, tar, and crystalline salts adhering to the equipment surface to become brittle, shrink, and crack, and are then blown away, thereby achieving online unblocking, solving equipment blockage problems, and ensuring the long-term stable operation of the desulfurization purification unit. The pipelines and nozzles used are those commonly known in the art.

[0145] In this embodiment, the outlet of the desulfurization purification unit 2 can also be connected to the shell-side inlet of the GGH heat exchanger in the heat exchange and temperature control unit 1, and the shell-side outlet of the GGH heat exchanger in the heat exchange and temperature control unit 1 can also be connected to the inlet of the absorption tower 301 in the decarbonization and regeneration unit 3. This connection method can both cool the desulfurized and purified coal gas to below 40°C to meet the temperature requirements for the desulfurized and purified coal gas to enter the decarbonization and regeneration unit 3, and heat the blast furnace gas in the heat exchange and temperature control unit 1 to meet the temperature requirements for entering the desulfurization purification unit 2, thus realizing the full utilization of heat resources.

[0146] The working principle of the radial flushing reaction tower 6 in this embodiment is as follows: the reaction gas enters the outer cavity composed of the radial flushing reaction tower shell 601 and the outer cylinder 604 from front to back through the first reaction gas channel 623 and the third reaction gas channel 625, and then passes horizontally through the outer cylinder gas channel 621 on the outer cylinder 604, the packing 7, and the inner cylinder gas channel 622 on the inner cylinder 605. Finally, the reaction gas flows to the next section through the second reaction gas channel 624.

[0147] The flushing principle of the outer bore 604 in the radial flushing reaction tower 6 is as follows: flushing gas or flushing liquid flows from multiple outer bore flushing ports 606 through the first inlet hose 608 and the outer bore flushing pipe branch pipe 631 to the outer bore flushing pipe 607. The flushing gas or flushing liquid is then distributed from the outer bore flushing pipe 607 to each outer bore nozzle 628. The flushing gas or flushing liquid is sprayed from the outer bore nozzle 628 onto the surface of the outer bore 604 for cleaning. The flushing gas or flushing liquid forms a long strip-shaped flushing area in the horizontal direction on the surface of the outer bore 604. After the axial reciprocating assembly 616 is started, the outer bore flushing pipe 607 can move up and down in the axial direction, which in turn drives the outer bore nozzle 628 to move up and down in the axial direction, making the long strip-shaped flushing area into a surface area, thus increasing the flushing area.

[0148] The flushing principle of the inner cylinder 605 in the radial flushing reaction tower 6 is as follows: flushing gas or flushing liquid flows from the inner cylinder flushing port 610 through the second inlet hose 612 to the inner cylinder flushing pipe 611. The flushing gas or flushing liquid is then distributed from the inner cylinder flushing pipe 611 to each inner cylinder nozzle 629. The flushing gas or flushing liquid is sprayed from the inner cylinder nozzle 629 onto the surface of the inner cylinder 605 for cleaning. The flushing gas or flushing liquid forms a long strip-shaped flushing area in the vertical direction on the surface of the inner cylinder 605. After the drive motor 618 is started, the rotation of the output shaft of the drive motor 618 drives the inner cylinder flushing pipe 611 and the inner cylinder nozzle 629 to rotate circumferentially, so that the long strip-shaped flushing area in the vertical direction is flushed in a complete circle.

[0149] Example 2: This embodiment provides a combined method for blast furnace gas desulfurization, decarbonization, and online unblocking. This method utilizes the combined blast furnace gas desulfurization, decarbonization, and online unblocking device described in Embodiment 1. The method specifically includes the following steps: Step 1, Adjust the temperature: Using the GGH heat exchanger in the heat exchange and temperature control unit 1, the media on both sides of the GGH heat exchanger are blast furnace gas and desulfurized purified gas, respectively. The temperature of the blast furnace gas is adjusted to 60℃~90℃ to obtain gas with adjusted temperature.

[0150] In this embodiment, the blast furnace gas input to the heat exchange and temperature control unit 1 in step one is the gas after passing through the blast furnace dust collector and the blast furnace gas residual pressure turbine generator. The temperature of the blast furnace gas is 30℃~60℃ or greater than or equal to 90℃, and the pressure of the blast furnace gas is 10~20kPa. The blast furnace gas residual pressure turbine generator is a commonly used blast furnace gas residual pressure turbine generator known in the art, abbreviated as TRT.

[0151] In step one, the temperature of the blast furnace gas is adjusted from 30℃~60℃ or greater than or equal to 90℃ to 60℃~90℃ to obtain the blast furnace gas with adjusted temperature. In step two, the temperature of the desulfurized and purified blast furnace gas is 60℃~90℃. When the temperature of the blast furnace gas input in step one is 30℃~60℃, the desulfurized and purified blast furnace gas is used to heat the blast furnace gas to fully utilize its own heat. The insufficient heat is supplemented by a heater to adjust the temperature of the blast furnace gas to 60℃~90℃. The heat source of the heater is waste steam or waste hot water from the plant area. When the temperature of the blast furnace gas is greater than or equal to 90℃, the cooler in the heat exchange temperature control unit 1 is used to adjust the temperature of the blast furnace gas to 60℃~90℃. The cold source of the cooler is the plant's circulating cooling water. Furthermore, in this embodiment, the temperature of the blast furnace gas input in step one is greater than or equal to 90℃, and a cooler is used for cooling.

[0152] Step 2, Desulfurization: The coal gas obtained in step one after temperature adjustment is passed into the dechlorination pretreatment reaction tower 201 in the desulfurization and purification unit 2, and then through the hydrolysis reaction tower 202 and the adsorption reaction tower 203 to obtain the clean coal gas after desulfurization and purification.

[0153] In step two, Cl in dechlorination pretreatment reaction tower 201 - The removal of H2S to ≤1mg / Nm³; COS conversion rate ≥95% during inorganic sulfur conversion in hydrolysis reaction tower 202; H2S removal to ≤1mg / Nm³ during desulfurization and purification in adsorption reaction tower 203.

[0154] In this embodiment, the purified coal gas obtained in step two needs to have its temperature reduced to below 40°C before entering the decarbonization and regeneration unit 3. There are two methods for cooling this gas. The first method involves passing the purified coal gas from step two into the GGH heat exchanger in the heat exchange and temperature control unit 1 for heat exchange before entering the decarbonization and regeneration unit 3. The temperature of the purified coal gas in the GGH heat exchanger is reduced to below 40°C to accommodate the carbon dioxide chemical absorption reaction temperature. The second method involves installing a cooler before the decarbonization and regeneration unit 3. The cooler's cold source is the plant's circulating cooling water, which reduces the temperature of the purified coal gas from step two to below 40°C. The cooler used is a commonly known cooler in the art. Furthermore, this embodiment specifically employs the second method, i.e., installing a cooler before the decarbonization and regeneration unit 3.

[0155] Step 3, decarbonization: The desulfurized and purified coal gas obtained in step two is introduced into the absorption tower 301 of the decarbonization and regeneration unit 3. Using an amine solution or ammonia water as the absorbent, carbon dioxide in the desulfurized and purified coal gas is absorbed in the absorption tower 301 by chemical absorption. The rich liquid after carbon dioxide absorption enters the desorption tower 303 for desorption and regeneration to obtain regenerated carbon dioxide gas. The decarbonized purified coal gas is then output and stored for later use.

[0156] In step three, when absorbing carbon dioxide from the desulfurized and purified coal gas, the carbon dioxide absorption rate is ≥90%; when desorption and regeneration are carried out in desorption tower 303, the regenerated carbon dioxide concentration is ≥95%.

[0157] Step 4, liquefaction: The regenerated carbon dioxide gas obtained in step three is introduced into the liquid carbon dioxide preparation unit 4, and the regenerated carbon dioxide gas is converted into industrial-grade or food-grade liquid carbon dioxide products using a liquefaction distillation process.

[0158] In this embodiment, the liquefaction distillation process used in step four to convert the regenerated carbon dioxide gas into industrial-grade or food-grade liquid carbon dioxide products is a commonly used liquefaction distillation process known in the art.

[0159] Step 5, online congestion clearing: A portion of the liquid carbon dioxide product obtained in step four is extracted and fed into the dry ice preparation, storage and distribution unit 5 to form dry ice particles, while the other portion is output and stored for later use as liquid carbon dioxide product. The dry ice particles are then sprayed through the dry ice preparation, storage and distribution unit 5 onto the orifice plate of the radial flushing reaction tower 6 in the desulfurization purification unit 2, as well as the tube bundles and other easily clogged parts of the heat exchanger in the heat exchange temperature control unit 1, to achieve online unclogging.

[0160] In step five, the dry ice particles have a diameter of 1–3 mm.

[0161] In this embodiment, step five involves using a dry ice forming machine to form dry ice particles from liquid carbon dioxide. The liquid carbon dioxide enters the dry ice forming machine through a pipe, where it is throttled, depressurized, and cooled to form a powdery solid. This powder is then extruded through a mold to form granular dry ice. The dry ice forming machine is a commonly used type known in the art.

[0162] In this embodiment, the injection pressure during injection in step five is 1-2 MPa.

[0163] In this embodiment, the dry ice used in the orifice plates of the dechlorination pretreatment reaction tower 201, hydrolysis reaction tower 202, and adsorption reaction tower 203 in the online desulfurization and purification unit 2, as well as the heat exchanger in the heat exchange and temperature control unit 1, is recycled throughout the entire combined unit. The dry ice particles are vaporized during the cleaning process and then return to the clean coal gas after desulfurization and purification. Finally, they enter the decarbonization and regeneration unit 3 through the second reaction gas channel 624 of the adsorption reaction tower 203, where they are reabsorbed and captured. They are then remade into dry ice particles in the liquid carbon dioxide preparation unit 4 and the dry ice preparation, storage, and distribution unit 5 for use.

Claims

1. A combined device for desulfurization, decarbonization and online unblocking of blast furnace gas, comprising a heat exchange and temperature control unit, wherein the outlet of the heat exchange and temperature control unit is connected to the inlet of the desulfurization and purification unit, and the outlet of the desulfurization and purification unit is connected to the inlet of the decarbonization and regeneration unit. The desulfurization purification unit comprises a dechlorination pretreatment reaction tower, a hydrolysis reaction tower, and an adsorption reaction tower connected sequentially from front to back; characterized in that: The dechlorination pretreatment reaction tower, hydrolysis reaction tower, and adsorption reaction tower mentioned above are all radial flushing reaction towers; The outlet of the decarbonization and regeneration unit is connected to the inlet of the liquid carbon dioxide preparation unit, and the outlet of the liquid carbon dioxide preparation unit is connected to the inlet of the dry ice preparation, storage and distribution unit. The outlet of the dry ice preparation, storage and distribution unit is also connected to the flushing port of the heat exchange and temperature control unit. The radial flushing reaction tower includes a closed radial flushing reaction tower shell. The internal cavity of the radial flushing reaction tower shell is a mounting cavity. A bottom plate is horizontally arranged near the bottom of the mounting cavity. The outer side wall of the bottom plate is fixedly connected to the inner side wall of the radial flushing reaction tower shell along the circumference. The mounting cavity at the upper part of the bottom plate is an axial upper section mounting cavity, and the mounting cavity at the lower part of the bottom plate is an axial lower section mounting cavity. The upper axial section of the mounting cavity is coaxially fitted with a cylindrical outer tube that is open at both axial ends. The upper axial end of the outer tube is fixedly connected to the top inner wall of the radial flushing reaction tower shell, and the lower axial end of the outer tube is fixedly connected to the upper part of the base plate. Inside the outer tube, a cylindrical inner tube that is open at both axial ends is also coaxially fitted. The upper axial end of the inner tube is fixedly connected to the top inner wall of the radial flushing reaction tower shell, and the lower axial end of the inner tube is fixedly connected to the upper part of the base plate. The radial flushing reaction tower shell is also provided with multiple external cylinder flushing ports, which are evenly distributed circumferentially on the upper part of the bottom plate. The axial upper section of the mounting cavity is also provided with multiple external cylinder flushing pipes. The multiple external cylinder flushing pipes are evenly arranged circumferentially between the inner side wall of the radial flushing reaction tower shell and the outer side wall of the external cylinder. Each external cylinder flushing pipe is arranged axially and is connected to the external cylinder flushing port through the first inlet hose. The radial flushing reaction tower shell is also provided with an inner tube flushing port, which is located at the upper axial end of the inner tube. An inner bore flushing pipe is also provided axially within the upper axial section of the mounting cavity. The axial ends of the external cylinder flushing pipe are closed, and multiple axial reciprocating components are installed on the side wall of the radial flushing reaction tower shell. The axial reciprocating components enable the external cylinder flushing pipe to move up and down along the axial direction. The outlet of the dry ice preparation, storage and distribution unit is also connected to the flushing port of the outer cylinder of the dechlorination pretreatment reaction tower, the hydrolysis reaction tower and the adsorption reaction tower, respectively. The outlet of the dry ice preparation, storage and distribution unit is also connected to the flushing port of the inner cylinder of the dechlorination pretreatment reaction tower, the hydrolysis reaction tower and the adsorption reaction tower.

2. The combined device for blast furnace gas desulfurization, decarbonization, and online unblocking as described in claim 1, characterized in that, Each of the aforementioned outer cylinder flushing pipes is provided with multiple radially penetrating outer cylinder nozzles near the outer cylinder side. The multiple outer cylinder nozzles are evenly distributed along the axial direction, and an outer cylinder nozzle is installed at each outer cylinder nozzle. The inner bore flushing pipe is coaxially fitted inside the inner bore, and the upper axial end of the inner bore flushing pipe is connected to the inner bore flushing port through a second inlet hose. The inner bore flushing pipe is also provided with multiple inner bore nozzles that penetrate the sidewalls radially. The multiple inner bore nozzles are evenly distributed along the axial direction, and an inner bore nozzle is installed at each inner bore nozzle.

3. The combined device for blast furnace gas desulfurization, decarbonization, and online unblocking as described in claim 2, characterized in that, The inner wall of the radial flushing reaction tower shell is also equipped with multiple outer tube support guides. The multiple outer tube support guides are evenly distributed along the axial and circumferential directions. Each outer tube support guide is connected to the outer tube flushing pipe. The multiple outer tube support guides can support and guide the outer tube flushing pipe when it moves up and down along the axial direction. The radial flushing reaction tower shell is also equipped with a drive motor. The output shaft of the drive motor is coaxially arranged with the inner cylinder flushing pipe. The inner cylinder flushing pipe can be driven by the output shaft of the drive motor to achieve circumferential rotation around its own central axis. The inner wall of the inner cylinder is also equipped with multiple inner tube support guides. These multiple inner tube support guides are evenly distributed along the axial direction and can support and guide the inner cylinder flushing pipe when it rotates in the circumferential direction.

4. The combined device for blast furnace gas desulfurization, decarbonization, and online unblocking as described in claim 3, characterized in that, The cavity between the inner wall of the outer bore and the outer wall of the inner bore is a filler cavity, which is filled with filler. The outer cylinder is also provided with multiple radially penetrating gas channels on its sidewall, and the multiple gas channels are evenly distributed along the axial and circumferential directions respectively. The inner cylinder is also provided with multiple radially penetrating gas channels on its sidewall, and the multiple gas channels are evenly distributed along the axial and circumferential directions respectively. The radial flushing reaction tower shell is provided with a first reaction gas channel at the lower axial end and a second reaction gas channel at the upper axial end; the bottom plate is also provided with a plurality of third reaction gas channels, which are arranged between the outer cylinder and the radial flushing reaction tower shell. A swivel joint is also installed at the connection between the inner tube flushing pipe and the second inlet hose.

5. The combined device for blast furnace gas desulfurization, decarbonization, and online unblocking as described in claim 4, characterized in that, The feed inlet of the heat exchange and temperature control unit is connected to the blast furnace gas transmission pipeline; The heat exchange and temperature control unit includes a heat exchanger; the heat exchanger includes one or more combinations of a GGH heat exchanger, a heater, and a cooler. The first channel of the dechlorination pretreatment reaction tower is connected to the outlet of the heat exchange and temperature control unit; the dechlorination pretreatment reaction tower contains a calcium-based or alumina-based dechlorinating agent to adsorb hydrogen chloride impurities in the coal gas to remove Cl. - The hydrolysis reaction tower contains a built-in γ-Al2O3-based hydrolysant to convert organic sulfur into inorganic sulfur; the adsorption reaction tower contains a built-in iron oxide-based or activated carbon-based adsorbent to remove inorganic sulfur, thereby achieving desulfurization and purification of the coal gas and obtaining clean coal gas after desulfurization and purification. The decarbonization and regeneration unit includes an absorption tower, the inlet of which is connected to the second channel of the reaction gas of the adsorption reaction tower, the outlet of which is connected to the inlet of the absorption tower and the auxiliary equipment of the desorption tower, the outlet of which is connected to the inlet of the desorption tower, and the outlet of the desorption tower is connected to the inlet of the liquid carbon dioxide preparation unit. The absorption tower and desorption tower auxiliary equipment include one or more combinations of cooling tower, lean and rich liquid heat exchanger and scrubbing tower; The liquid carbon dioxide production unit includes one or more combinations of a compressor, an ice machine, a precooler, a distillation column, a condenser, a subcooler, and a product storage tank. The dry ice preparation, storage and distribution unit includes one or more combinations of an expansion chamber, a dry ice pellet mill, a dry ice insulation box and conveying equipment and pipelines.

6. A combined method for desulfurization, decarbonization, and online unblocking of blast furnace gas, characterized in that, This method employs a combined device for blast furnace gas desulfurization, decarbonization, and online unblocking as described in any one of claims 1 to 5; the method specifically includes the following steps: Step 1, Adjust the temperature: Using the GGH heat exchanger in the heat exchange and temperature control unit, the media on both sides of the GGH heat exchanger are blast furnace gas and desulfurized purified gas, respectively. The temperature of the blast furnace gas is adjusted to 60℃~90℃ to obtain gas with adjusted temperature. Step 2, Desulfurization: The coal gas obtained in step one after temperature adjustment is fed into the dechlorination pretreatment reaction tower in the desulfurization and purification unit, and then passes through the hydrolysis reaction tower and the adsorption reaction tower to obtain the clean coal gas after desulfurization and purification. Step 3, decarbonization: The desulfurized and purified coal gas obtained in step two is introduced into the absorption tower of the decarbonization and regeneration unit. Using amine solution or ammonia water as absorbent, carbon dioxide in the desulfurized and purified coal gas is absorbed in the absorption tower by chemical absorption method. The rich liquid after carbon dioxide absorption enters the desorption tower for desorption and regeneration to obtain regenerated carbon dioxide gas. The decarbonized purified coal gas is then output and stored for later use. Step 4, liquefaction: The regenerated carbon dioxide gas obtained in step three is fed into the liquid carbon dioxide preparation unit, and the regenerated carbon dioxide gas is converted into industrial-grade or food-grade liquid carbon dioxide products using a liquefaction distillation process. Step 5, online congestion clearing: A portion of the liquid carbon dioxide product obtained in step four is extracted and fed into the dry ice preparation, storage and distribution unit to form dry ice pellets, while the other portion is stored as liquid carbon dioxide product for later use. The dry ice pellets are then sprayed into the orifice plate of the radial flushing reaction tower of the desulfurization purification unit and the tube bundle of the heat exchanger in the heat exchange and temperature control unit through the dry ice preparation, storage and distribution unit to achieve online unblocking.

7. The combined method for blast furnace gas desulfurization, decarbonization, and online unblocking as described in claim 6, characterized in that, In step one, the temperature of the blast furnace gas is adjusted from 30℃~60℃ or greater than or equal to 90℃ to 60℃~90℃ to obtain the gas with adjusted temperature.

8. The combined method for blast furnace gas desulfurization, decarbonization, and online unblocking as described in claim 6, characterized in that, In step two, the Cl in the dechlorination pretreatment reaction tower - The removal of H2S to ≤1mg / Nm³; the COS conversion rate during inorganic sulfur conversion in the hydrolysis reaction tower is ≥95%; the removal of H2S to ≤1mg / Nm³ during desulfurization and purification in the adsorption reaction tower.

9. The combined method for blast furnace gas desulfurization, decarbonization, and online unblocking as described in claim 6, characterized in that, In step three, when absorbing carbon dioxide from the desulfurized and purified coal gas, the carbon dioxide absorption rate is ≥90%; when desorption and regeneration are carried out in the desorption tower, the regenerated carbon dioxide concentration is ≥95%.

10. The combined method for blast furnace gas desulfurization, decarbonization, and online unblocking as described in claim 6, characterized in that, In step five, the dry ice particles have a particle size of 1–3 mm.

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