Integrated denitration and dehydrocarbon ceramic filter tube

Abstract

This utility model discloses an integrated denitrification and dehydrocarbonization ceramic filter tube, belonging to the field of industrial flue gas purification technology. The filter tube adopts a two-section integrated structure, including a lower denitrification section and an upper dehydrocarbonization section. The bottom of the denitrification section is equipped with a base with a larger outer diameter, ensuring overall structural stability. The dehydrocarbonization section is internally constructed with a porous honeycomb carrier, whose channels can be filled with a dehydrocarbonization catalyst. The denitrification and dehydrocarbonization sections are seamlessly connected by a socket structure, allowing the flue gas to complete the denitrification and dehydrocarbonization reactions sequentially within a single filter tube. This utility model, through functional partitioning design, solves the problems of easy clogging and short catalyst life in traditional ceramic filter tubes, achieving highly efficient synergistic purification of nitrogen oxides (NOx) and non-methane total hydrocarbons (NMHCs), and has the advantages of compact structure, convenient installation, and high purification efficiency.

Description

Technical Field

[0001] This invention belongs to the field of industrial flue gas purification technology, specifically relating to a multifunctional integrated ceramic filter tube, and more particularly to an integrated denitrification and dehydrocarbonization ceramic filter tube that can simultaneously and efficiently remove nitrogen oxides (NOx) and non-methane total hydrocarbons (NMHCs). Background Technology

[0002] In recent years, with the in-depth implementation of the "ultra-low emission" policy in the coal-fired power industry, the flue gas emission standards of industrial kilns such as glass kilns, coke ovens, and biomass boilers have become increasingly stringent, and multi-pollutant synergistic control technology has become a research hotspot.

[0003] Traditional ceramic filter tubes, by incorporating denitrification agents, have achieved integrated dust removal and denitrification, effectively reducing process steps and floor space. However, industrial flue gas commonly contains organic pollutants such as non-methane hydrocarbons (NMHCs), especially in industries like coking and glass manufacturing. When these NMHCs are directly released into the atmosphere, they undergo photochemical reactions with nitrogen oxides, generating ozone and secondary organic aerosols. These are significant precursors to photochemical smog and fine particulate matter (PM2.5) pollution, posing a serious threat to the environment and human health.

[0004] Currently, there is a lack of integrated technologies capable of simultaneously and efficiently removing dust, NOx, and NMHCs within a single device. Simply mixing and coating denitrification agents and dehydrocarbonization catalysts onto traditional filter tubes can easily lead to catalyst deactivation and pore blockage due to incompatible physicochemical properties. Therefore, there is an urgent need for a novel ceramic filter tube with a rational structure, functional zones, and the ability to synergistically purify multiple pollutants. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an integrated denitrification and dehydrocarbonization ceramic filter tube with a stable structure, clear functional division, resistance to clogging, and long catalyst life.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An integrated denitrification and dehydrocarbonization ceramic filter tube includes a denitrification section and a dehydrocarbonization section seamlessly connected by a socket structure. The lower part of the denitrification section is a solid support base, and the upper part is a cavity structure with denitrification function; the outer diameter of the solid support base is larger than the outer diameter of the upper part of the denitrification section and the outer diameter of the dehydrocarbonization section, and the base provides stable support and a sealing surface for the entire filter tube. The dehydrogenation section is a hollow tubular structure with a porous honeycomb structure inside, and the honeycomb channels can be filled with a dedicated dehydrogenation catalyst. The inner and outer diameters of the denitrification section and the dehydrogenation section are matched at the connection point to ensure that the flue gas can flow through the denitrification section and the dehydrogenation section in sequence, so as to achieve the sequential removal and synergistic purification of NOx and NMHCs.

[0007] Preferably, the ceramic filter tube adopts a "side-in, top-out" airflow path: flue gas enters from the side wall of the denitrification section, and dust is filtered and NOx is catalytically converted when passing through the cavity of the denitrification section; then the flue gas enters the dehydrogenation section, flows through a porous honeycomb structure filled with dehydrogenation catalyst, and NMHCs are catalytically oxidized; finally, the purified gas is discharged from the top of the dehydrogenation section.

[0008] Preferably, the total length of the ceramic filter tube is 80±5cm. The length ratio of the denitrification cavity to the dehydrogenation section is (2-3):1, and the volume of the dehydrogenation section accounts for 25%-35% of the total filter tube volume. This design ratio ensures sufficient residence time for both catalytic reactions and avoids excessive pressure drop caused by an excessively long filter tube.

[0009] Preferably, the porous honeycomb structure inside the dehydrogenation section has a pore size of 0.8–1.5 mm, a honeycomb pore density of 200–400 cpsi, and a wall thickness of 0.2–0.3 mm. This structure ensures sufficient specific surface area and catalytic reaction interface while exhibiting low gas flow resistance.

[0010] Preferably, the outer diameter of the solid support base for the denitrification section is 18–22 cm; the outer diameter of the top of the denitrification section and the dehydrogenation section is 14–16 cm; and the inner diameter of the denitrification section and the dehydrogenation section are the same, both being 9–11 cm. This size design allows for a compact arrangement of the filter tubes within the reactor, and the base provides good installation stability.

[0011] The useful effects of this utility model are as follows: (1) Strong structural integrity: The denitrification section is an integral structure including a solid base. It has a compact structure, strong integrity, and high mechanical strength, avoiding the risk of cracking at the connection due to thermal stress. (2) Clear functional zoning: The denitrification section undertakes the supporting and primary denitrification functions, while the dehydrocarbonization section is independently responsible for deep dehydrocarbonization. The gas flow path is clear, and the two catalytic reactions do not interfere with each other, resulting in high synergistic purification efficiency. (3) Anti-clogging and long life: The dehydrogenation section uses an independent porous honeycomb carrier to fill the catalyst, instead of mixing or coating it with the denitrification catalyst. This avoids the mutual influence between different catalysts and the micropore blockage caused by dust accumulation, which significantly extends the life of the dehydrogenation catalyst. (3) Easy installation: The solid base at the bottom of the denitrification section forms a natural load-bearing and sealing surface, which is convenient for installation and fixation in the reactor. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the integrated denitrification and dehydrocarbonization ceramic filter tube of this utility model.

[0013] In the diagram: 1. Denitrification section; 2. Hydrocarbon removal section; Detailed Implementation

[0014] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0015] Please see Figure 1 The embodiments of this utility model will be further described below with reference to the accompanying drawings.

[0016] An integrated denitrification and dehydrocarbonization ceramic filter tube includes a denitrification section 1 and a dehydrocarbonization section 2. The filter tube is a ceramic fiber filter tube doped with a denitrification agent, and the denitrification section is used to remove NOx. The outer diameter of the base of the denitrification section is the largest, at 20 cm, while the outer diameter of the top of the denitrification section is 15 cm and the inner diameter is 10 cm.

[0017] The outer diameter of the dehydrogenation section matches that of the top of the denitration section, which is 15 cm, while the inner diameter is 10 cm. Its interior is a porous honeycomb ceramic structure with a pore size of 1.2 mm and a pore density of 300 cpsi. The honeycomb channels can be filled with a dehydrogenation catalyst with a thickness of about 17 cm.

[0018] The total length of the filter tube is set at 83cm. The base of the denitrification section is 3cm high, and the cavity is 60cm long; the dehydrogenation section is 20cm long, with a length ratio of 3:1, and the volume of the dehydrogenation section accounts for 30%.

[0019] The working process is as follows: High-temperature flue gas (e.g., 300-400℃) enters from the side wall of denitrification section 1. Inside the denitrification section cavity, dust is filtered out, and NOx is catalytically converted by the denitrification filter tubes. The preliminarily purified flue gas then enters the dehydrocarbonization section 2, flowing through porous honeycomb channels filled with dehydrocarbonization catalyst, where NMHCs are catalytically oxidized to CO2 and H2O. Finally, the clean flue gas is discharged from the top of dehydrocarbonization section 2.

[0020] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An integrated denitrification and dehydrocarbonization ceramic filter tube, characterized in that, This includes a denitrification section and a dehydrocarbonization section that are seamlessly connected by a socket-type structure; The lower part of the denitrification section is a solid support base, and the upper part is a cavity structure with denitrification function; the outer diameter of the solid support base is larger than the outer diameter of the upper part of the denitrification section and the dehydrogenation section. The dehydrogenation section is a hollow tubular structure with a porous honeycomb structure inside. The channels of the porous honeycomb are filled with a dehydrogenation catalyst for removing NMHCs. The inner and outer diameters of the connection between the denitrification section and the dehydrogenation section are matched to form a continuous channel through which the flue gas flows sequentially between denitrification and dehydrogenation.

2. The integrated denitrification and dehydrocarbonization ceramic filter tube according to claim 1, characterized in that, The porous honeycomb has a pore size of 0.8-1.5 mm, a honeycomb pore density of 200-400 cpsi, and a wall thickness of 0.2-0.3 mm.

3. The integrated denitrification and dehydrocarbonization ceramic filter tube according to claim 1, characterized in that, The thickness of the dehydrogenation catalyst layer is 16-18 cm.

4. The integrated denitrification and dehydrocarbonization ceramic filter tube according to claim 1, characterized in that, The total length of the ceramic filter tube is 80±5cm, and the length ratio of the hollow part of the denitrification section to the length of the dehydrogenation section is (2~3):1; The total volume of the dehydrocarbonization section accounts for 25% to 35% of the total volume of the filter tube.

5. The integrated denitrification and dehydrocarbonization ceramic filter tube according to claim 1, characterized in that, The diameter of the ceramic filter tube is as follows: The outer diameter of the denitrification section base of the ceramic filter tube is 18-22 cm; The top diameter of the ceramic filter tube denitrification section and the outer diameter of the dehydrogenation section are 14-16 cm. The inner diameter of the denitrification and dehydrogenation sections of the ceramic filter tube is 9–11 cm.

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