Mobile off-line thermal regeneration device for SCR (Selective Catalytic Reduction) catalyst

Abstract

The utility model discloses a movable SCR (Selective Catalytic Reduction) catalyst offline thermal regeneration device which comprises a thermal regeneration box A, a thermal regeneration box B, a hot air circulating fan A and a hot air circulating fan B, wherein the hot air circulating fan A and the hot air circulating fan B are correspondingly arranged; the hot air circulating fan A and the hot air circulating fan B are respectively connected with the electric heater through a first three-way valve; the other end of the electric heater is respectively connected with the heat regeneration box A and the heat regeneration box B through a second three-way valve; an air supplement valve is arranged between the electric heater and the heat regeneration box A, and an air supplement valve is arranged between the electric heater and the heat regeneration box B. The two sides of the first three-way valve are respectively provided with an exhaust valve.

Description

Technical Field

[0001] The utility model relates to the field of catalyst regeneration, in particular to a mobile SCR catalyst off-line thermal regeneration device. Background Art

[0002] As domestic environmental protection requirements gradually increase, the flue gas denitrification of various waste power plants has been upgraded from the original SNCR to SCR. However, due to the particularity of the flue gas purification process of waste power plants, the flue gas SCR denitrification is conventionally arranged at the tail of the flue gas purification. However, after the front-end deacidification and heavy metal removal, the flue gas temperature at the outlet of the bag filter is conventionally 145°C. SCR denitrification mostly uses medium and low temperature catalysts, and the reaction temperature is controlled at 180°C to 220°C, so the energy consumption is relatively low. However, in a low temperature environment, crystals of ammonium sulfate will appear. This substance is adhesive and will stick to the catalyst surface, blocking the catalyst active surface and affecting the denitrification efficiency. Therefore, the low-temperature catalyst needs to be regenerated regularly to restore its activity, or replaced with a new catalyst.

[0003] Catalyst thermal regeneration technology can be divided into two types according to its function: "online thermal regeneration" and "offline thermal regeneration". Online thermal regeneration is to set up a bypass in the SCR system, switch to the bypass through the flue gas damper door, and the flue gas will go through the bypass, and thermal regeneration will be carried out in the SCR reactor.

[0004] However, since many projects do not have regeneration devices designed during the construction period, the utility model develops a movable SCR catalyst thermal regeneration device. The entire device is in a skid-mounted form, which is easy to install and use. Utility Model Content

[0005] In view of the deficiencies in the prior art, the utility model provides a mobile SCR catalyst off-line thermal regeneration device, which can be used for SCR catalyst thermal regeneration.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] A mobile SCR catalyst offline thermal regeneration device comprises a thermal regeneration box A, a thermal regeneration box B, and correspondingly arranged hot air circulation fans A and hot air circulation fans B; the hot air circulation fans A and hot air circulation fans B are respectively connected to an electric heater through a first three-way valve; the other end of the electric heater is respectively connected to the thermal regeneration box A and the thermal regeneration box B through a second three-way valve; an air supply valve is respectively arranged between the electric heater and the thermal regeneration box A and the thermal regeneration box B, and an exhaust valve is respectively arranged on both sides of the first three-way valve.

[0008] As a further solution of the utility model, a first temperature sensor is provided at the outlet of the electric heater, and a gas concentration detector is provided on the inlet pipe.

[0009] As a further solution of the present invention, a connecting valve is provided between the hot air circulation fans A and B.

[0010] As a further solution of the utility model, it also includes a mobile cart, which is used to transport the catalyst to the thermal regeneration box A and the thermal regeneration box B.

[0011] As a further solution of the utility model, the heat regeneration box A and the heat regeneration box B are respectively located in a sealed box, and the sealed box is provided with a second temperature sensor.

[0012] As a further solution of the utility model, the outlet of the electric heater is connected to the heat regeneration box A and the heat regeneration box B through a hot air circulation inlet pipe.

[0013] The utility model has the following beneficial effects:

[0014] The utility model can remove the ammonium salt component causing the catalyst to be deactivated offline by means of thermal regeneration, so as to restore the activity of the catalyst.

[0015] In order to more clearly illustrate the structural features and functions of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of the embodiment of the present utility model. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with the accompanying drawings and related knowledge, and described clearly and completely. Obviously, the described application is only a part of the embodiments of the present invention, rather than all the embodiments.

[0018] The sulfur oxides and water vapor in the existing industrial flue gas inevitably react with the reducing gas ammonia to form ammonium bisulfate, which can block the pore structure of the catalyst and cover the surface active sites, resulting in reduced denitration efficiency. Therefore, the deposition of ammonium sulfate on the catalyst surface has become the main obstacle to the industrial application of low-temperature SCR denitration process. The utility model removes the ammonium salt component that causes the catalyst to be deactivated offline by thermal regeneration to restore its activity.

[0019] Reference Figure 1As shown, the utility model provides a mobile SCR catalyst offline thermal regeneration device, including a thermal regeneration box A1 and a thermal regeneration box B2, which are used for heating and regenerating the catalyst, and correspondingly arranged hot air circulation fans A3 and hot air circulation fans B4, which are used for circulating hot air; the hot air circulation fans A3 and B4 are respectively connected to the electric heater 6 through a first three-way valve 5, which can play a role in hot air circulation; the other end of the electric heater 6 is respectively connected to the thermal regeneration box A1 and the thermal regeneration box B2 through a second three-way valve 7, so as to form a complete circulation loop; an air supply valve 8 is respectively arranged between the electric heater 6 and the thermal regeneration box A and the thermal regeneration box B, which is used to supply air to the heated gas and can cool the gas according to demand, and an exhaust valve 9 is respectively arranged on both sides of the first three-way valve 5 to allow the exhausted flue gas to enter the inlet flue of the deacidification tower of the garbage incineration; in Figure 1 The invention also includes a mobile trolley 10, which is used to transport the catalyst 11 to the thermal regeneration box A and the thermal regeneration box B to facilitate the transportation of the catalyst.

[0020] Reference Figure 1 As shown, the electric heater outlet 15 is provided with a first temperature sensor 11 for detecting the outlet temperature, and the inlet pipe is provided with a gas concentration detector 12 for detecting the SO2 concentration in the circulating gas. It should be noted that when the SO2 concentration is low, the loop formed by the heating gas is: electric heater → heat regeneration box A or heat regeneration box B → hot air circulation fan A or hot air circulation fan B → electric heater; when the SO2 concentration is high, the gas discharged by the hot air circulation fan A or hot air circulation fan B is discharged through the exhaust valve 9, and the flue gas generated by decomposition enters the inlet flue of the deacidification tower of the garbage incineration, or a part of it is discharged, which can be set as needed. And the electric heater outlet 15 is connected to the hot regeneration box A and the hot regeneration box B through the hot air circulation air inlet pipe 16.

[0021] In a preferred embodiment of the utility model, a connecting valve 13 is provided between the hot air circulation fans A and the hot air circulation fans B. In the utility model, the hot regeneration box A or the hot regeneration box B is working each time, that is, each regeneration is performed through one of the hot regeneration boxes A or the hot regeneration box B. When the regeneration is completed, the temperature of the catalyst is relatively high. Through the connection of the connecting valve 13, the remaining heat can be used to preheat the next catalyst.

[0022] In a preferred embodiment of the utility model, the heat regeneration box A and the heat regeneration box B are respectively located in a sealed box, and the sealed box is provided with a second temperature sensor 14. Further preferably, the heat regeneration box A and the heat regeneration box B are respectively located in a sealable sealed box, and the regeneration temperature is detected by the second temperature sensor 14. If the temperature is high, it can be adjusted by supplying air or setting the heater, etc.

[0023] In a preferred embodiment of the utility model, the device of the utility model can be a container-type movable type, which is easy to install at the project site and can be transported to another project by a trailer for catalyst regeneration.

[0024] Further preferably, four wheels with brakes (rubber wheels) are provided at the bottom of the box to facilitate the transport of the device, and the catalyst enters and exits the heating and regeneration device automatically by using an external transmission mechanism of a trolley;

[0025] The regeneration device of the utility model is equipped with a power regulator for a variable frequency fan and a heater, which can accurately control the fan air volume and the heater temperature through a PLC system, and can automatically control the switching of five groups of air valves to automatically realize the heating and cooling process.

[0026] In the utility model, the regeneration device is innovatively divided into two left and right heating chambers, namely, heat regeneration boxes A / B. After heating is completed in one of the boxes, the waste heat can be transferred to the other side for preheating during the cooling process, thereby improving work efficiency and being energy-saving and environmentally friendly.

[0027] Moreover, the inlet and outlet trolleys and the circulating heating air ducts in the regeneration device of the utility model are both provided with wind speed adjustment and rectification devices, which can ensure that the heated air is evenly distributed through each hole of the catalyst, thereby achieving uniform heating and avoiding secondary crystallization of ammonium sulfate caused by kicking.

[0028] In addition, the upper part of the regeneration device is equipped with an automatic SO2 flue gas monitoring device, which can monitor the sulfur dioxide concentration generated during the thermal regeneration of the denitrification catalyst in real time, effectively control the start and stop time cycle of the exhaust fan, reduce heat loss during the thermal regeneration process, and accurately determine the end point of the catalyst thermal regeneration, control the catalyst thermal regeneration time, and achieve the purpose of energy saving and consumption reduction.

[0029] The utility model uses an automatic exhaust and automatic air supply system, which can be controlled by a built-in PLC program. When a certain regeneration time is reached, the exhaust is automatically performed, and the air supply valve is automatically opened to replace the air supply. At the same time, the online automatic monitoring device feeds back the exhaust SO2 value. When SO2 is reduced to the set process parameter, it means that the thermal regeneration has ended, and the system thermal regeneration box A starts to automatically cool down, and the thermal regeneration box B heats up.

[0030] In some preferred embodiments, the device is integrated with a PLC control program, and the operating programs of various equipment, instruments, control valves, etc. are integrated into the PLC, which can achieve one-button start and automatic control with a high degree of automation.

[0031] In the utility model, during the working process, the catalyst is removed from the SCR denitration reactor → the catalyst 11 is transferred into the heat regeneration box A by using the mobile trolley 10 → preheating starts → heating to a preset temperature → PID adjusts the constant temperature → the flue gas generated by the decomposition of ammonium sulfate salt enters the inlet flue of the deacidification tower of the waste incineration → the regeneration heating is stopped after the SO2 concentration of the heating furnace flue is detected in real time to meet the standard → the catalyst is cooled and the high temperature of the waste heat of the catalyst is transferred to the heat regeneration box B on the other side → the catalyst in the heat regeneration box B is preheated → the catalyst in A is cooled and then enters the dust removal work → it is loaded into the SCR denitration reactor again.

[0032] The technical principle of the utility model is described above in combination with the specific embodiments, which are only the preferred implementation methods of the utility model. The protection scope of the utility model is not limited to the above embodiments, and all technical solutions under the idea of ​​the utility model belong to the protection scope of the utility model. Those skilled in the art can think of other specific implementation methods of the utility model without creative labor, and these methods will fall within the protection scope of the utility model.

Claims

1. A mobile SCR catalyst offline thermal regeneration device, characterized in that: It includes a heat regeneration box A, a heat regeneration box B, and corresponding hot air circulation fans A and hot air circulation fans B; the hot air circulation fans A and hot air circulation fans B are respectively connected to the electric heater through a first three-way valve; the other end of the electric heater is respectively connected to the heat regeneration box A and the heat regeneration box B through a second three-way valve; an air supply valve is respectively arranged between the electric heater and the heat regeneration box A and the heat regeneration box B, and an exhaust valve is respectively arranged on both sides of the first three-way valve.

2. A mobile SCR catalyst offline thermal regeneration device as claimed in claim 1, characterized in that: The outlet of the electric heater is provided with a first temperature sensor, and the inlet pipe is provided with a gas concentration detector.

3. A mobile SCR catalyst offline thermal regeneration device as claimed in claim 2, characterized in that: A connecting valve is provided between the hot air circulation fans A and B.

4. A mobile SCR catalyst offline thermal regeneration device as claimed in claim 3, characterized in that: It also includes a mobile cart, which is used to transport the catalyst to the thermal regeneration box A and the thermal regeneration box B.

5. A mobile SCR catalyst offline thermal regeneration device as claimed in claim 4, characterized in that: The heat regeneration box A and the heat regeneration box B are respectively located in a sealed box, and the sealed box is provided with a second temperature sensor.

6. A mobile SCR catalyst offline thermal regeneration device as claimed in claim 5, characterized in that: The outlet of the electric heater is connected to the heat regeneration box A and the heat regeneration box B through the hot air circulation air inlet pipe.

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