VOCs waste gas catalytic combustion treatment equipment with built-in heat exchange structure

Abstract

The invention relates to the technical field of VOCs waste gas treatment, and discloses VOCs waste gas catalytic combustion treatment equipment with a built-in heat exchange structure, the VOCs waste gas catalytic combustion treatment equipment comprises a catalytic combustion unit and a plurality of adsorption units, activated carbon adsorption assemblies are arranged in the adsorption units and used for adsorbing organic compounds in waste gas, and in the same time period, the activated carbon adsorption assemblies are used for adsorbing the organic compounds in the waste gas. One part of the adsorption units are used for absorbing organic compounds in gas discharged from the filtering device, the other part of the adsorption units are standby, when absorption is saturated, desorption steam enters the saturated adsorption units for desorption after being heated by the catalytic combustion unit, and the standby adsorption units replace the desorption steam to participate in absorption of the organic compounds. Through the arrangement of the back flushing tank, gas in the back flushing tank is heated by utilizing heat of steam, so that air in the back flushing tank is heated to expand, and high-pressure airflow is generated to reversely purge the filter, on one hand, the effect of cleaning the filter is achieved, and on the other hand, heat generated by catalytic combustion is further effectively utilized.

Description

Technical Field

[0001] The invention relates to the technical field of VOCs waste gas treatment, and in particular to a VOCs waste gas catalytic combustion treatment device with a built-in heat exchange structure. Background Art

[0002] For the treatment of large-volume, low-concentration organic waste gas, the current mainstream process is "adsorption concentration + desorption treatment". Adsorption concentration is the adsorption of pollutants through porous media such as zeolite molecular sieves and activated carbon. Common post-desorption treatment methods include catalytic combustion, incineration, condensation recovery, etc. Activated carbon has a large adsorption capacity and low price, and catalytic combustion is low-temperature and efficient. Therefore, activated carbon adsorption and desorption plus catalytic combustion technology is more common in the treatment of large-volume, low-concentration organic waste gas.

[0003] Catalytic combustion VOCs waste gas treatment equipment is an efficient and environmentally friendly technical equipment, which is specially used to treat volatile organic compounds (VOCs) waste gas generated in industrial production processes. It converts organic matter in the waste gas into harmless carbon dioxide and water through catalytic oxidation reaction, thereby achieving the purpose of purifying the waste gas. During the catalytic combustion process, a large amount of heat will be generated, and if this part of the heat is allowed to dissipate naturally, it will undoubtedly cause a large waste of resources. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a VOCs waste gas catalytic combustion treatment device with a built-in heat exchange structure, which solves the current problem of heat generated by catalytic combustion being wasted.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a VOCs waste gas catalytic combustion treatment device with a built-in heat exchange structure, including a catalytic combustion unit and a plurality of adsorption units, wherein the adsorption unit is provided with an activated carbon adsorption component for adsorbing organic compounds in the waste gas, and in the same period of time, a part of the adsorption unit is used to absorb the organic compounds in the gas discharged from the filtering device, and the other part of the adsorption unit is used as a standby. When the absorption is saturated, the desorption steam is heated by the catalytic combustion unit and enters the saturated adsorption unit for the desorption step, and the standby adsorption unit replaces it to participate in the absorption of organic compounds, and the desorbed organic compounds are used as a standby adsorption unit. The mixture of the desorbed matter and the steam enters the catalytic combustion unit for catalytic combustion treatment. The filtering device comprises a filter, the input end of the filter is connected to the exhaust gas pipe, the filter has two output ends, one of which is connected to the adsorption unit, and the other is connected to the back-blowing tank, and a pressure detection valve is arranged between the two. A spiral heat dissipation pipe is arranged in the back-blowing tank, and part of the desorbed steam heated by the catalytic combustion unit flows in the spiral heat dissipation pipe and heats the gas in the back-blowing tank. When the air pressure in the back-blowing tank exceeds the set value of the pressure detection valve, the gas in the back-blowing tank is ejected to reversely purge the inside of the filter.

[0006] Preferably, the adsorption unit has two air inlets and two air outlets, and valves are provided at the air inlets and the air outlets. One of the air inlets is connected to the filtering device through an air inlet pipe, and the corresponding air outlet is connected to the emission mechanism through an exhaust pipe 1. The exhaust gas is filtered by the filtering device to remove particulate impurities, enters the adsorption unit through the air inlet pipe to remove organic compound components, and is finally transported to the emission mechanism through the exhaust pipe 1 for discharge.

[0007] Preferably, the discharge mechanism comprises a discharge fan, an air inlet end of the discharge fan is connected to an exhaust pipe, and an exhaust end of the discharge fan is connected to a chimney.

[0008] Preferably, the catalytic combustion unit is divided into a catalytic combustion zone and a heat exchange zone, the two are isolated from each other, and a heat exchanger is arranged between the two. The heat exchanger exchanges the heat energy generated in the catalytic combustion zone and transports it to the heat exchange zone. A desorption airflow output pipe runs through the heat exchange zone, one end of the desorption airflow output pipe is connected to the steam generating equipment, and the other end is connected to another air inlet of the adsorption unit. The other air outlet of the adsorption unit is connected to the heat exchange zone through a desorption airflow reflux pipe. A desorption fan is also arranged between the heat exchange zone and the catalytic combustion zone. The desorbed organic compounds are mixed with steam and preheated in the heat exchange zone before being transported to the catalytic combustion zone by the desorption fan.

[0009] Preferably, the catalytic combustion zone is connected to the chimney through exhaust pipe 2, and the desorbed organic compounds are converted into carbon dioxide and water through catalytic combustion treatment and discharged to the outside through the chimney.

[0010] Preferably, both ends of the spiral heat dissipation pipe respectively penetrate the back-blowing tank body and are respectively connected to the desorption airflow output pipe and the desorption airflow return pipe. Part of the desorption steam enters the spiral heat dissipation pipe from the desorption airflow output pipe and then directly enters the desorption airflow return pipe.

[0011] Preferably, a flow regulating valve is provided between the spiral heat dissipation pipe and the desorption airflow output pipe, for regulating the flow of the desorption steam entering the spiral heat dissipation pipe.

[0012] The present invention provides a VOCs waste gas catalytic combustion treatment device with a built-in heat exchange structure. It has the following beneficial effects: The present invention, through the setting of the catalytic combustion unit, utilizes the heat generated by the catalytic combustion of the catalytic combustion unit to heat the steam used for desorption, so that the steam temperature is increased to meet the desorption requirements, thereby realizing the reuse of the heat generated by the catalytic combustion, thereby avoiding the problem of waste of resources. At the same time, through the setting of the back-blowing tank, the heat of the steam is utilized to heat the gas in the back-blowing tank, so that the air inside the tank is heated and expanded, and a high-pressure airflow is generated to reversely purge the filter, which, on the one hand, achieves the effect of cleaning the filter, increases the service life of the filter, and reduces the maintenance cost of the filter, and on the other hand, realizes the further effective utilization of the heat generated by the catalytic combustion. At the same time, the setting of the flow regulating valve is utilized so that it can cooperate with the desorption fan to perform real-time regulation on the flow of the desorption steam and the concentration of organic compounds in the gas after desorption, thereby realizing the optimal concentration ratio of the catalytic combustion, and ensuring the efficiency and effect of the catalytic combustion. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a rear perspective view of a VOCs waste gas catalytic combustion treatment device with a built-in heat exchange structure according to the present invention; Figure 2 It is a front perspective view of a VOCs waste gas catalytic combustion treatment device with a built-in heat exchange structure according to the present invention; Figure 3 It is a front view of a VOCs waste gas catalytic combustion treatment device with a built-in heat exchange structure according to the present invention; Figure 4 It is a three-dimensional schematic diagram of the catalytic combustion unit in the present invention; Figure 5 It is a schematic diagram of a part of the internal structure of the catalytic combustion unit in the present invention; Figure 6 It is a schematic diagram of the structure of the filtering device in the present invention; Figure 7 It is a schematic diagram of the internal structure of the back-blowing tank in the present invention.

[0014] Among them, 1. catalytic combustion unit; 101. catalytic combustion zone; 102. heat exchange zone; 103. heat exchanger; 104. desorption fan; 105. exhaust pipe 2; 2. adsorption unit; 3. filter; 4. air inlet pipe; 5. exhaust pipe 1; 6. exhaust fan; 7. chimney; 8. desorption airflow output pipe; 9. desorption airflow reflux pipe; 10. valve; 11. backblowing tank; 12. pressure detection valve; 13. flow control valve; 14. spiral heat dissipation pipe. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] Please see attached Figure 1 -Attached Figure 7 The embodiment of the present invention provides a VOCs waste gas catalytic combustion treatment device with a built-in heat exchange structure, including a catalytic combustion unit 1 and a plurality of adsorption units 2. The adsorption unit 2 is provided with an activated carbon adsorption component for adsorbing organic compounds in the waste gas. In the same period, a part of the adsorption unit 2 is used to absorb the organic compounds in the gas discharged from the filtering device, and the other part of the adsorption unit 2 is reserved. When the absorption is saturated, the desorption steam is heated by the catalytic combustion unit 1 and enters the saturated adsorption unit 2 for the desorption step. The spare adsorption unit 2 replaces it to participate in the absorption of organic compounds. The desorbed organic compounds are mixed with the steam and enter the catalytic combustion unit Catalytic combustion treatment is carried out in element 1, and the filtering device includes a filter 3. The input end of the filter 3 is connected to the exhaust gas pipeline. The filter 3 is provided with two output ends, one of which is connected to the adsorption unit 2, and the other is connected to the back-blowing tank 11, and a pressure detection valve 12 is arranged between the two. A spiral heat dissipation pipe 14 is arranged in the back-blowing tank 11. Part of the desorbed steam heated by the catalytic combustion unit 1 flows in the spiral heat dissipation pipe 14 and heats the gas in the back-blowing tank 11. When the air pressure in the back-blowing tank 11 exceeds the set value of the pressure detection valve 12, the gas in the back-blowing tank 11 is ejected to reversely purge the inside of the filter 3.

[0017] By setting up the catalytic combustion unit 1, the heat generated by the catalytic combustion of the catalytic combustion unit 1 is used to heat the steam used for desorption, so that the steam temperature is increased to meet the desorption requirements, thereby realizing the reuse of the heat generated by the catalytic combustion, thereby avoiding the problem of waste of resources. At the same time, by setting up the back-blowing tank 11, the heat of the steam is used to heat the gas in the back-blowing tank 11, so that the air inside the back-blowing tank 11 expands due to the heat, generating a high-pressure airflow to reversely purge the filter 3. On the one hand, the effect of cleaning the filter 3 is achieved, the service life of the filter 3 is increased, and the maintenance cost of the filter 3 is reduced. On the other hand, further effective utilization of the heat generated by the catalytic combustion is achieved.

[0018] The adsorption unit 2 is provided with two air inlets and two air outlets, and valves 10 are provided at the air inlets and the air outlets. One of the air inlets is connected to the filtering device through the air inlet pipe 4, and the corresponding air outlet is connected to the emission mechanism through the exhaust pipe 5. The exhaust gas is filtered by the filtering device to remove particulate impurities, enters the adsorption unit 2 through the air inlet pipe 4 to remove organic compound components, and is finally transported to the emission mechanism through the exhaust pipe 5 for discharge.

[0019] The industrial waste gas is filtered by the filter device to remove particulate impurities therein, and then enters the adsorption unit 2 with the valve 10 opened through the intake pipe 4. Through the intermolecular van der Waals force, the activated carbon adsorption component adsorbs the organic compound components in the waste gas in the pores, thereby achieving the purpose of purifying the waste gas.

[0020] It should be noted that, in the adsorption unit 2 used for the step of adsorbing organic compounds, the valve 10 connected to the air inlet pipe 4 and the exhaust pipe 5 is in an open state, and another set of valves 10 at the air inlet and the air outlet are in a closed state.

[0021] The discharge mechanism includes a discharge fan 6, the air inlet end of the discharge fan 6 is connected to the exhaust pipe 5, and the exhaust end is connected to the chimney 7.

[0022] By utilizing the suction force generated by the operation of the exhaust fan 6 , the exhaust gas can flow sequentially through the filter 3 , the air inlet pipe 4 , the adsorption unit 2 , and the exhaust pipe 5 , and finally be discharged through the chimney 7 .

[0023] The catalytic combustion unit 1 is divided into a catalytic combustion zone 101 and a heat exchange zone 102, which are isolated from each other and a heat exchanger 103 is arranged between the two. The heat exchanger 103 exchanges the heat energy generated in the catalytic combustion zone 101 and transports it to the heat exchange zone 102. A desorption airflow output pipe 8 runs through the heat exchange zone 102. One end of the desorption airflow output pipe 8 is connected to the steam generating device, and the other end is connected to another air inlet of the adsorption unit 2. The other air outlet of the adsorption unit 2 is connected to the heat exchange zone 102 through the desorption airflow return pipe 9. A desorption fan 104 is also arranged between the heat exchange zone 102 and the catalytic combustion zone 101. The desorbed organic compounds are mixed with steam and preheated in the heat exchange zone 102, and then transported to the catalytic combustion zone 101 by the desorption fan 104. The catalytic combustion zone 101 is connected to the chimney 7 through the exhaust pipe 2 105. The desorbed organic compounds are converted into carbon dioxide and water through catalytic combustion treatment and discharged to the outside through the chimney 7.

[0024] Catalytic combustion uses the active sites on the surface of the catalyst to make oxygen molecules and pollutants react on the catalyst surface, reduce the reaction activation energy, and improve the reaction efficiency, so that the oxidation reaction that originally occurred at more than 600°C can be carried out at 250-300°C, and the purification efficiency is generally not less than 95%. Organic pollutants are oxidized and decomposed to generate CO2 and H2O and release a large amount of heat, thereby achieving the purpose of purifying exhaust gas. The catalyst usually uses precious metals such as Pd and Pt as active components and transition metal oxides, molecular sieves, etc. as carriers. The final products of catalytic combustion treatment of pollutants are pollution-free CO2 and H2O.

[0025] When the activated carbon adsorption component in a part of the adsorption unit 2 is saturated with organic compounds, it will lose the ability to continue to adsorb organic compounds, but this ability is reversible. The catalytic combustion zone 101 continues to catalytically burn the organic compounds, and the heat generated is transported to the heat exchange zone 102 through the heat exchanger 103, so that the temperature in the heat exchange zone 102 increases, and part of the desorption airflow output pipe 8 is located in the heat exchange zone 102. Of course, in order to improve efficiency, part of the circulation pipe of the heat exchanger 103 can be used to wrap the desorption airflow output pipe 8, or part of the circulation pipe of the heat exchanger 103 can be directly located in the desorption airflow output pipe 8, so that the steam in the desorption airflow output pipe 8 is fully heated to achieve the desorption conditions. At the same time, the mixed airflow after desorption also enters the heat exchange zone 102, and is preheated by the heat therein to a temperature close to the catalytic combustion temperature, and then enters the catalytic combustion zone 101, thereby reducing the operating pressure of the catalytic combustion bed in the catalytic combustion zone 101, and further realizing the rational use of thermal energy.

[0026] Both ends of the spiral heat dissipation tube 14 respectively penetrate the tank body of the back-blowing tank 11 and are respectively connected to the desorption airflow output pipe 8 and the desorption airflow return pipe 9. Part of the desorption steam enters the spiral heat dissipation tube 14 from the desorption airflow output pipe 8 and directly enters the desorption airflow return pipe 9.

[0027] When the desorption step is performed, the desorption steam flows in the desorption airflow output pipe 8, the saturated adsorption unit 2 and the desorption airflow return pipe 9, and also flows in the spiral heat dissipation pipe 14, so that the high-temperature desorption steam heats the gas in the back-blowing tank 11, so that the temperature in the back-blowing tank 11 increases, and the air pressure also increases accordingly. When the air pressure exceeds the set value of the pressure detection valve 12, the pressure detection valve 12 opens, and the gas in the back-blowing tank 11 forms a high-pressure airflow and is ejected to reversely purge the inside of the filter 3. Such a design, on the one hand, achieves the effect of cleaning the filter 3, increases the service life of the filter 3, and reduces the maintenance cost of the filter 3, and on the other hand, achieves further effective utilization of the heat generated by catalytic combustion.

[0028] A flow regulating valve 13 is provided between the spiral heat dissipation tube 14 and the desorption airflow output tube 8 , and is used to regulate the flow of the desorption steam entering the spiral heat dissipation tube 14 .

[0029] Affected by various uncontrollable factors, the desorption effect of the desorption steam on the activated carbon adsorption component in the adsorption unit 2 may change, resulting in a change in the concentration of the organic compound that finally enters the catalytic combustion zone 101. When the concentration of the organic compound is too low, the efficiency of the catalytic combustion will be reduced, and when the concentration of the organic compound is too high, the catalytic combustion will be insufficient. In order to achieve the most ideal catalytic combustion effect, it is necessary to regulate the proportion of the organic compound concentration. The desorption fan 104 can achieve a part of the flow control effect. However, relying solely on this control method will have the problem of low control progress and poor effect. The flow control valve 13 is used to regulate the flow of the desorption steam entering the spiral heat pipe 14 to achieve an auxiliary control effect on the final organic compound concentration. The combination of the two improves the control effect.

[0030] By setting the flow control valve 13, it can cooperate with the desorption fan 104 to adjust the flow of the desorption steam and the concentration of organic compounds in the gas after desorption in real time, thereby achieving the optimal concentration ratio of catalytic combustion and ensuring the efficiency and effect of catalytic combustion. At the same time, by adjusting the flow of the desorption steam entering the spiral heat dissipation pipe 14 by the flow control valve 13, the spiral heat dissipation pipe 14 can be quickly dissipated to increase the total amount of gas entering the back-blowing tank 11, thereby increasing the flow of the subsequent back-blowing flow and improving the back-blowing effect.

[0031] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A VOCs waste gas catalytic combustion treatment device with a built-in heat exchange structure, comprising a catalytic combustion unit (1) and a plurality of adsorption units (2), characterized in that: The adsorption unit (2) is provided with an activated carbon adsorption component for adsorbing organic compounds in the exhaust gas. In the same period of time, a part of the adsorption unit (2) is used to absorb the organic compounds in the gas discharged from the filtering device, and another part of the adsorption unit (2) is reserved. When the absorption is saturated, the desorption steam is heated by the catalytic combustion unit (1) and enters the saturated adsorption unit (2) to perform the desorption step. The spare adsorption unit (2) replaces it to participate in the absorption of organic compounds. The desorbed organic compounds are mixed with the steam and enter the catalytic combustion unit (1) for catalytic combustion treatment. The filtering device comprises a filter (3). The filter (3) The input end is connected to the exhaust gas pipeline. The filter (3) has two output ends, one of which is connected to the adsorption unit (2) and the other is connected to the back-blowing tank (11). A pressure detection valve (12) is provided between the two. A spiral heat dissipation pipe (14) is provided in the back-blowing tank (11). Part of the desorbed steam heated by the catalytic combustion unit (1) flows in the spiral heat dissipation pipe (14) and heats the gas in the back-blowing tank (11). When the gas pressure in the back-blowing tank (11) exceeds the set value of the pressure detection valve (12), the gas in the back-blowing tank (11) is ejected to perform reverse purge on the inside of the filter (3).

2. The VOCs waste gas catalytic combustion treatment equipment with a built-in heat exchange structure according to claim 1 is characterized in that: The adsorption unit (2) is provided with two air inlets and two air outlets, and valves (10) are provided at the air inlets and the air outlets. One of the air inlets is connected to the filter device through an air inlet pipe (4), and the corresponding air outlet is connected to the emission mechanism through an exhaust pipe (5). The exhaust gas is filtered by the filter device to remove particulate impurities, enters the adsorption unit (2) through the air inlet pipe (4) to remove organic compound components, and is finally transported to the emission mechanism through the exhaust pipe (5) for discharge.

3. The VOCs waste gas catalytic combustion treatment equipment with a built-in heat exchange structure according to claim 2 is characterized in that: The discharge mechanism comprises a discharge fan (6), the air inlet end of the discharge fan (6) being connected to the first exhaust pipe (5), and the exhaust end of the discharge fan (6) being connected to the chimney (7).

4. The VOCs waste gas catalytic combustion treatment equipment with a built-in heat exchange structure according to claim 3 is characterized in that: The catalytic combustion unit (1) is divided into a catalytic combustion zone (101) and a heat exchange zone (102), which are isolated from each other and a heat exchanger (103) is arranged between the two. The heat exchanger (103) exchanges the heat energy generated in the catalytic combustion zone (101) and transports it to the heat exchange zone (102). A desorption airflow output pipe (8) runs through the heat exchange zone (102). One end of the desorption airflow output pipe (8) is connected to a steam generating device, and the other end is connected to another air inlet of the adsorption unit (2). The other air outlet of the adsorption unit (2) is connected to the heat exchange zone (102) through a desorption airflow return pipe (9). A desorption fan (104) is also arranged between the heat exchange zone (102) and the catalytic combustion zone (101). The desorbed organic compounds are mixed with steam and preheated in the heat exchange zone (102) before being transported to the catalytic combustion zone (101) by the desorption fan (104).

5. The VOCs waste gas catalytic combustion treatment equipment with a built-in heat exchange structure according to claim 4 is characterized in that: The catalytic combustion zone (101) is connected to the chimney (7) via the second exhaust pipe (105); the desorbed organic compounds are converted into carbon dioxide and water through catalytic combustion and discharged to the outside through the chimney (7).

6. The VOCs waste gas catalytic combustion treatment equipment with a built-in heat exchange structure according to claim 4 is characterized in that: Both ends of the spiral heat dissipation pipe (14) respectively penetrate the tank body of the back-blowing tank (11) and are respectively connected to the desorption airflow output pipe (8) and the desorption airflow return pipe (9); part of the desorption steam enters the spiral heat dissipation pipe (14) from the desorption airflow output pipe (8) and then directly enters the desorption airflow return pipe (9).

7. The VOCs waste gas catalytic combustion treatment equipment with a built-in heat exchange structure according to claim 6 is characterized in that: A flow regulating valve (13) is provided between the spiral heat dissipation tube (14) and the desorption airflow output tube (8) for regulating the flow of desorption steam entering the spiral heat dissipation tube (14).

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