Low-backpressure industrial denitration catalytic box

Abstract

The utility model discloses a low back pressure industrial denitration catalytic box relates to waste gas treatment technical field, including shell and outer mount, the middle part of shell is provided with the central channel, and the shell and the central channel form annular clearance, and the outer mount is fixed in the annular clearance. Waste gas flows into the outer side of the center channel from the annular gap formed by the shell and the center channel and penetrates through the hole part of the center channel and the catalyst carrier installed in the hole part, harmful substances in the waste gas are eliminated, and the treated waste gas enters the inner side of the center channel and then flows out from the tail end of the center channel. Therefore, waste gas flow forms an inward gathering passage in the catalytic box, the situation that waste gas flows in a straight line in a traditional catalytic box is changed, meanwhile, through the structural design of the catalytic box, it is guaranteed that the inflow sectional area of catalyst carrier gas flow is far larger than the inflow sectional area of gas flow of the traditional catalytic box, and the structure can better meet the requirement for ultra-low back pressure.

Description

Technical Field

[0001] The utility model relates to the technical field of waste gas treatment, in particular to an industrial denitration catalytic box with low back pressure. Background Art

[0002] In the industrial field, waste gas treatment systems are commonly used to eliminate polluted waste gas. Catalytic decomposition technology is usually used to treat pollutants, such as industrial denitrification, industrial VOCs elimination, and industrial CO removal. The industries involved are: chemical, steel, cement, power generation, internal combustion engines, printing, papermaking, etc.

[0003] Among them, catalytic technology is to mix catalytically active substances and various auxiliary materials into catalyst slurry, coat and fix it on the surface tissue of the carrier, and form a large number of catalytic active sites on the microstructure of the surface tissue. When the exhaust gas containing harmful substances passes through the catalyst surface, the exhaust gas molecules come into contact with the catalytically active substances. Under certain reaction conditions, a catalytic reaction occurs to eliminate the harmful substances in the exhaust gas.

[0004] The catalyst box is used as a carrier for implementing catalytic technology and is used to load and carry catalysts. The catalyst carrier is installed and arranged in the catalyst box, and the catalyst box provides a reaction flow channel for the exhaust gas flow. The layout of the catalyst carrier needs to be designed according to the engineering target requirements, which is related to the exhaust gas flow characteristics, exhaust gas treatment efficiency, back pressure and other parameters.

[0005] In the field of industrial denitration, especially for gas turbines, gas boilers and other equipment, the back pressure requirements for the exhaust gas denitration system are very high, usually 200Pa, and some are even lower, up to 100Pa. If the back pressure of the exhaust gas denitration system exceeds the standard, it will affect the output of the equipment. The back pressure can be appropriately reduced by selecting the catalyst carrier, but the reduction is limited. When ultra-low back pressure is required, it is difficult to meet the requirements by selecting and optimizing the catalyst carrier alone.

[0006] Specifically, depending on the conditions at the denitration project site, the traditional installation method of the catalyst box is a straight-through type, that is, the flow direction of the exhaust gas discharged from the source exhaust pipe is in a straight line with the channel direction of the catalyst honeycomb carrier, that is, the flow of the exhaust gas in the catalyst box is a straight line. In the traditional straight-through catalyst box, when the airflow flows through the catalyst box, the back pressure is related to the flow cross-sectional area of ​​the catalyst box and the effective length of the catalyst box (that is, the height of the carrier): the back pressure is inversely proportional to the flow cross-sectional area of ​​the catalyst box and is proportional to the effective length of the catalyst box; in order to reduce the back pressure, the flow cross-sectional area of ​​the catalyst box is often increased and the height of the carrier is reduced. However, due to the actual size and space limitations of the project, the flow cross-sectional area of ​​the catalyst box cannot be very large, which will result in a large occupied space area. Therefore, in order to meet the needs of ultra-low back pressure, the traditional straight-through catalyst box structure is difficult to meet engineering needs. Utility Model Content

[0007] The utility model aims to solve the problem that the traditional straight-through catalytic box structure in the prior art is difficult to meet the ultra-low back pressure requirement due to the actual size and space limitation, and proposes a low back pressure industrial denitrification catalytic box.

[0008] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a low back pressure industrial denitrification catalytic box, including an outer shell and an external fixed frame, a central channel is arranged in the middle of the outer shell, and an annular gap is formed between the outer shell and the central channel, a partition is fixedly connected to the middle of the outer side of the central channel, the partition is provided with a plurality of groups of through holes, a plurality of groups of catalyst carriers are tightly fixedly installed around the outer side of the central channel, a blind plate is fixedly connected to one end of the central channel, and a tail plate is fixedly connected to the annular gap position of the other end of the outer shell and the central channel.

[0009] Preferably, the shell and the central channel are fixedly connected via a plurality of groups of partitions, and the plurality of groups of catalyst carriers are located on both sides of the partitions.

[0010] Preferably, the cross-sectional shape of the central channel may be polygonal or circular.

[0011] Compared with the prior art, the advantages and positive effects of the utility model are:

[0012] 1. In the utility model, the exhaust gas flow flows from the annular gap formed by the outer shell and the central channel into the outside of the central channel, the hole portion of the central channel and the catalyst carrier installed in the hole portion, the catalyst carrier catalyzes the exhaust gas to eliminate harmful substances in the exhaust gas, and the treated exhaust gas enters the inner side of the central channel and then flows out from the tail end of the central channel, thereby the exhaust gas flow forms an inwardly converging passage in the catalyst box, changing the situation that the exhaust gas flows in a straight line in the traditional catalyst box. At the same time, through the structural design of the catalyst box, it is ensured that the catalyst carrier airflow inflow cross-sectional area is much larger than the airflow inflow cross-sectional area of ​​the traditional catalyst box, and the cross-sectional area of ​​the central channel and the airflow inflow cross-sectional area around the catalyst box are larger than the cross-sectional area of ​​the exhaust gas airflow pipe, and the structure can better meet the needs of ultra-low back pressure.

[0013] 2. In the utility model, a partition is provided between the outer shell and the central channel of the catalyst box. The partition plays the role of supporting the catalyst carrier. The catalyst carrier can be designed to be smaller, which is convenient for replacement and maintenance. While ensuring that the catalyst box effectively eliminates harmful substances in the exhaust gas, its service life is extended. At the same time, the partition is hollowed out with multiple groups of through holes, and the airflow can flow around it, ensuring that the airflow flows evenly, thereby ensuring the catalytic quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a first three-dimensional structural schematic diagram of a low back pressure industrial denitration catalytic box proposed by the utility model;

[0015] Figure 2 A second three-dimensional structural schematic diagram of a low back pressure industrial denitration catalytic box is proposed for the utility model;

[0016] Figure 3 The utility model provides a first three-dimensional structural schematic diagram of the interior of an industrial denitration catalytic box with low back pressure;

[0017] Figure 4 A second three-dimensional structural schematic diagram of the interior of an industrial denitration catalytic box with low back pressure is proposed for the utility model;

[0018] Figure 5 A side view of the interior of an industrial denitration catalytic box with low back pressure is provided for the utility model;

[0019] Figure 6 The utility model provides a three-dimensional structural schematic diagram of the flow direction of the exhaust gas flow in the side air intake catalytic box of the industrial denitration catalytic box with low back pressure;

[0020] Figure 7 The utility model provides a cross-sectional schematic diagram of airflow flowing around a catalyst box in a low back pressure industrial denitration catalyst box.

[0021] Legend: 1. Outer shell; 2. External fixing frame; 3. Partition plate; 4. Through hole; 5. Catalyst carrier; 6. Blind plate; 7. Tail plate; 8. Center channel. DETAILED DESCRIPTION

[0022] In order to more clearly understand the above-mentioned purpose, features and advantages of the utility model, the utility model is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0023] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0024] Embodiment 1

[0025] like Figure 1-7As shown, the utility model provides an industrial denitrification catalytic box with low back pressure, including an outer shell 1 and an outer fixing frame 2, a central channel 8 is provided in the middle of the outer shell 1, and an annular gap is formed between the outer shell 1 and the central channel 8, a partition plate 3 is fixedly connected to the middle of the outer side of the central channel 8, and the partition plate 3 is provided with multiple groups of through holes 4, multiple groups of catalyst carriers 5 are tightly fixedly installed around the outer side of the central channel 8, a blind plate 6 is fixedly connected to one end of the central channel 8, a tail plate 7 is fixedly connected to the annular gap position of the other end of the outer shell 1 and the central channel 8, the outer shell 1 and the central channel 8 are fixedly connected via multiple groups of partition plates 3, and the multiple groups of catalyst carriers 5 are located on both sides of the partition plate 3.

[0026] The specific settings and functions of this embodiment are described in detail below: the end face of the low back pressure industrial denitration catalyst box in the air inlet direction is provided with a blind plate 6, the exhaust gas flow flows into the outside of the central channel 8 from the annular gap formed by the shell 1 and the central channel 8, the air flow passes through the open central channel 8 and the catalyst carrier 5 installed in the hole, the catalyst carrier 5 catalyzes the exhaust gas to eliminate harmful substances in the exhaust gas, the treated exhaust gas enters the inner side of the central channel 8, and then flows out from the tail end of the central channel 8, the central channel 8 is open around, so that the air flow flows from the outer side of the central channel to the inner side, thereby the exhaust gas flow forms an inwardly gathered passage in the catalyst box, changing the situation that the exhaust gas flows in a straight line in the traditional catalyst box;

[0027] According to the size of the exhaust gas flow pipeline, the central channel 8 of the catalyst box is designed, and the cross-sectional area of ​​the central channel 8 is larger than the cross-sectional area of ​​the exhaust gas flow pipeline; according to the size of the exhaust gas flow pipeline, the airflow inflow area around the catalyst box is designed, and the airflow inflow area around the catalyst box is larger than the cross-sectional area of ​​the exhaust gas flow pipeline; the catalyst carrier 5 is arranged around the central channel 8 of the catalyst box, and the area of ​​the catalyst carrier 5 passing through the central channel 8 is much larger than the cross-sectional area of ​​the exhaust gas flow pipeline; under the condition of meeting the requirements of engineering design, the arrangement of the side air intake denitration catalyst box is more flexible, the length of the catalyst box and the height of the carrier can be adjusted according to actual requirements, and the structure can better meet the requirements of ultra-low back pressure;

[0028] The catalyst carrier 5 can be designed to be smaller, which is convenient for replacement and maintenance. While ensuring that the catalyst box effectively eliminates harmful substances in the exhaust gas, its service life is extended. There is a partition 3 between the shell 1 and the central channel 8 in the catalyst box, and the partition 3 plays the role of supporting the catalyst carrier 5. At the same time, the partition 3 is hollowed out with multiple groups of through holes 4, and the airflow can flow around, ensuring that the airflow around the four sides flows evenly, avoiding the excessive flow rate of the airflow on one side affecting the catalytic quality.

[0029] Embodiment 2

[0030] According to the actual needs of the project, the air intake area around the central channel 8 and the height of the catalyst carrier 5 are designed, and the flow rate and back pressure of the catalyst box are further calculated.

[0031] Specifically, taking an industrial denitration project as an example, the back pressure of the catalytic box of the utility model and the traditional straight-through catalytic box is compared to describe the beneficial effects brought by the utility model:

[0032] Engineering case parameters:

[0033] Exhaust gas flow pipe cross-sectional dimensions: length 1m, width 1m, cross-sectional area 1m 2 ;

[0034] Standard exhaust gas flow rate: 5000Nm 3 / h;

[0035] Design airspeed: 10000h -1 ;

[0036] Total volume of catalyst carrier: 0.5m 3 ;

[0037] Catalyst carrier open porosity: 80%.

[0038] The calculation of the traditional straight-through type and the catalyst box of the utility model is as follows:

[0039]

[0040] It can be seen that in this embodiment, the back pressure of the structure of the utility model is only 12.5% ​​of that of the traditional straight-through type while meeting the design requirements. It can be concluded that the back pressure of the denitration catalyst box of the utility model is significantly lower than that of the traditional straight-through type.

[0041] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A low back pressure industrial denitration catalytic box, comprising a housing (1) and an external fixing frame (2), characterized in that: A central channel (8) is provided in the middle of the shell (1), and an annular gap is formed between the shell (1) and the central channel (8). A partition (3) is fixedly connected to the middle of the outer side of the central channel (8), and each of the partitions (3) is provided with a plurality of groups of through holes (4).

2. The low back pressure industrial denitration catalytic box according to claim 1, characterized in that: A plurality of groups of catalyst carriers (5) are tightly fixedly installed around the outer side of the central channel (8).

3. The low back pressure industrial denitration catalytic box according to claim 1, characterized in that: A blind plate (6) is installed on the inlet side of the central channel (8), and a tail plate (7) is installed on the outlet side of the central channel (8).

4. The low back pressure industrial denitration catalytic box according to claim 1, characterized in that: The outer shell (1) and the central channel (8) are fixedly connected via a plurality of groups of partitions (3).

5. The low back pressure industrial denitration catalytic box according to claim 1, characterized in that: The cross-sectional shape of the central channel (8) is one of a polygon and a circle.

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