Waste gas combustion temperature adjusting system

Abstract

The utility model discloses a waste gas combustion temperature adjusting system, and belongs to the technical field of waste gas purification. A waste gas combustion temperature adjusting system comprises a control cabinet, a first temperature sensor, a second temperature sensor, a first oxygen adjusting valve, a second oxygen adjusting valve and a waste gas control valve. The first temperature sensor is mounted at the exhaust end of the first reactor; the second temperature sensor is mounted at the exhaust end of the second reactor; the first oxygen regulating valve is mounted at the gas inlet end of the first reactor; the second oxygen regulating valve is mounted at the gas inlet end of the second reactor; the control cabinet is electrically connected with the first temperature sensor and the second temperature sensor and used for detecting the exhaust gas temperature of the exhaust ends of the first reactor and the second reactor; the control cabinet is electrically connected with the first oxygen regulating valve and the second oxygen regulating valve and is used for controlling the rate of oxygen introduced into the first reactor and the second reactor.

Description

Technical Field

[0001] The utility model relates to the technical field of waste gas purification, and more specifically to a waste gas combustion temperature regulating system. Background Art

[0002] Acrylic acid, as an important chemical raw material, produces some harmful exhaust gases during its production process, such as volatile organic compounds (VOCs) and other emissions that may have a negative impact on the environment and human health. In order to control these emissions, catalytic combustion is usually used to purify the exhaust gas.

[0003] After searching the existing patent document with publication number CN105650651A, a method for purifying high-concentration organic waste gas is provided. The device sets a plurality of completely isolated catalyst beds in a catalytic combustion reactor, and controls the degree of catalytic combustion reaction by segmented oxygenation of each bed, thereby controlling the temperature of the organic waste gas in the bed. At the same time, the waste gas from each bed is timely led out for heat extraction. While recovering heat, the temperature of the waste gas after heat extraction can be controlled to meet the initial reaction temperature required for the next catalytic combustion reaction.

[0004] Although the device has many beneficial effects, it still has the following problems: when controlling the temperature, the device controls the oxygen supplementation amount of the inlet exhaust gas of each catalyst bed layer through the outlet temperature of each catalyst bed layer to prevent excessive oxygen from causing excessive combustion heat. Although this temperature control method can prevent catalyst sintering, it will lead to insufficient catalytic combustion reaction of exhaust gas, affecting the purification effect.

[0005] In view of this, we propose an exhaust gas combustion temperature regulation system. Utility Model Content

[0006] 1. Technical issues to be solved

[0007] The purpose of the utility model is to provide an exhaust gas combustion temperature regulating system to solve the problems raised in the above background technology.

[0008] 2. Technical solution

[0009] The utility model is realized by the following technical solutions:

[0010] An exhaust gas combustion temperature regulating system comprises a control cabinet, a first temperature sensor, a second temperature sensor, a first oxygen regulating valve, a second oxygen regulating valve, a first reactor, a second reactor and an exhaust gas control valve;

[0011] The exhaust end of the first reactor is connected to the intake end of the second reactor;

[0012] The first temperature sensor is installed at the exhaust end of the first reactor;

[0013] The second temperature sensor is installed at the exhaust end of the second reactor;

[0014] The first oxygen regulating valve is installed at the air inlet end of the first reactor;

[0015] The second oxygen regulating valve is installed at the air inlet end of the second reactor;

[0016] The exhaust gas control valve is installed at the air inlet end of the second reactor and is electrically connected to the control cabinet to control the concentration of organic matter discharged into the second reactor;

[0017] The control cabinet is electrically connected to the first temperature sensor and the second temperature sensor, and is used to detect the exhaust gas temperature at the exhaust end of the first reactor and the second reactor;

[0018] The control cabinet is electrically connected to the first oxygen regulating valve and the second oxygen regulating valve, and is used to control the rate of oxygen flowing into the first reactor and the second reactor.

[0019] As an optional solution of the technical solution of this application document, it also includes: a pressurized fan, a heat exchanger, a heater and a heat recovery device. The waste gas to be treated is introduced into the air inlet end of the first reactor through the pressurized fan, the heat exchanger and the heater.

[0020] As an optional solution of the technical solution of this application document, the exhaust end of the first reactor is connected to the heat exchanger and the heat recovery device, and the exhaust gas discharged from the first reactor is passed through the heat exchanger and the heat recovery device to the intake end of the second reactor;

[0021] A heat regulating valve is installed at the air inlet end of the heat recovery device, and a third temperature sensor is installed at the air inlet end of the second reactor. The third temperature sensor and the heat regulating valve are electrically connected to a control cabinet, and the control cabinet controls the opening of the heat regulating valve based on the signal of the third temperature sensor.

[0022] As an optional solution of the technical solution of this application document, the waste gas to be treated is introduced into the air inlet end of the first reactor through a pressurized fan, a heat exchanger, a heater, and a waste gas control valve.

[0023] As an optional solution of the technical solution of this application document, a pollutant analyzer is installed at the exhaust end of the second reactor, and the pollutant analyzer is electrically connected to the control cabinet.

[0024] 3. Beneficial effects

[0025] Compared with the prior art, the beneficial effects of the utility model are:

[0026] 1. The present application sets a first temperature sensor to collect the temperature of the exhaust end of the first reactor, and controls the opening of the first oxygen regulating valve according to the signal of the first temperature sensor, so as to control the reaction temperature in the first reactor within a set range, thereby avoiding excessive temperature in the first reactor and causing catalyst sintering.

[0027] 2. The present application adopts a third temperature sensor to collect the temperature of the exhaust gas introduced into the second reactor, and controls the heat regulating valve according to the signal of the third temperature sensor to achieve full recovery of heat.

[0028] 3. The present application adopts a second temperature sensor to collect the temperature of the exhaust gas discharged from the second reactor, and controls the temperature of the exhaust gas control valve according to the signal of the second temperature sensor, so as to realize dynamic adjustment of the concentration of organic matter in the exhaust gas entering the second reactor and increase the exhaust gas treatment efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the overall structure of an exhaust gas combustion temperature regulating system;

[0030] In the figure: 1. control cabinet; 2. first temperature sensor; 3. second temperature sensor; 4. first oxygen regulating valve; 5. second oxygen regulating valve; 6. first reactor; 7. second reactor; 8. pressurized fan; 9. heat exchanger; 10. heater; 11. heat recovery device; 12. heat regulating valve; 13. third temperature sensor; 14. exhaust gas control valve; 15. pollutant analyzer. DETAILED DESCRIPTION

[0031] The technical solution of the utility model will be clearly and completely described below in conjunction with the accompanying drawings.

[0032] See also Figure 1 The utility model provides an exhaust gas combustion temperature regulation system, comprising: a control cabinet 1, a first temperature sensor 2, a second temperature sensor 3, a first oxygen regulating valve 4, a second oxygen regulating valve 5, a first reactor 6, a second reactor 7, a pressurized fan 8, a heat exchanger 9, a heater 10, a heat recovery device 11 and an exhaust gas control valve 14.

[0033] The waste gas to be treated is pressurized by the booster fan 8, heated by the heat exchanger 9 and the heater 10, and passed into the first reactor 6 for primary combustion; the waste gas discharged from the first reactor 6 passes into the heat exchanger 9 and the heat recovery device 11 to achieve heat recovery, and then mixed with the waste gas treated by the booster fan 8, the heat exchanger 9 and the heater 10, and passed into the second reactor 7 for secondary combustion.

[0034] The first temperature sensor 2 is installed at the exhaust end of the first reactor 6; the second temperature sensor 3 is installed at the exhaust end of the second reactor 7; the first oxygen regulating valve 4 is installed at the intake end of the first reactor 6; the second oxygen regulating valve 5 is installed at the intake end of the second reactor 7; the exhaust gas control valve 14 is installed at the intake end of the second reactor 7 and is electrically connected to the control cabinet 1 for controlling the concentration of organic matter discharged into the second reactor 7; the control cabinet 1 is electrically connected to the first temperature sensor 2 and the second temperature sensor 3 for detecting the exhaust gas temperature at the exhaust end of the first reactor 6 and the second reactor 7; the control cabinet 1 is electrically connected to the first oxygen regulating valve 4 and the second oxygen regulating valve 5 for controlling the oxygen rate entering the first reactor 6 and the second reactor 7.

[0035] The first reactor 6 and the second reactor 7 are both provided with a catalyst bed, which is used for catalytic combustion of the exhaust gas. The maximum activity range of the catalyst is usually between 200°C and 400°C, so the reaction temperature in the first reactor 6 and the second reactor 7 needs to be controlled within the range of 200°C to 400°C. The concentration of organic matter introduced into the first reactor 6 is relatively high, generally between 30% and 60%. If the temperature is not controlled, the heat released during combustion will cause the catalyst to sinter, reduce the exhaust gas purification efficiency, and cause the pollutant emission to exceed the standard. Therefore, the temperature of the exhaust gas discharged from the first reactor 6 is detected by setting a first temperature sensor 2, and the opening of the first oxygen regulating valve 4 is controlled by the control cabinet 1. When the temperature is high, the opening of the first oxygen regulating valve 4 is reduced, and the temperature of the gas discharged from the first reactor 6 is controlled within 300°C to 500°C by reducing the concentration of the reactants and the reaction rate. The exhaust gas discharged from the first reactor 6 is then introduced into the second reactor 7 for secondary combustion to control the pollutant concentration within the standard range.

[0036] In order to fully utilize the thermal energy and avoid the exhaust gas temperature entering the second reactor 7 being lower than 200°C, it is necessary to install a heat regulating valve 12 at the air inlet end of the heat recovery device 11 and a third temperature sensor 13 at the air inlet end of the second reactor 7; the control cabinet 1 collects the temperature of the exhaust gas at the air inlet end of the second reactor 7 through the third temperature sensor 13, controls the opening of the heat regulating valve 12, and increases the opening of the heat regulating valve 12 when the exhaust gas temperature entering the second reactor 7 is too high, and reduces the opening of the heat regulating valve 12 when the exhaust gas temperature entering the second reactor 7 is low.

[0037] The organic matter concentration of the exhaust gas after the primary combustion is about 10%. In order to increase the exhaust gas treatment efficiency, the exhaust gas treated by the booster fan 8, the heat exchanger 9 and the heater 10 can be mixed with the exhaust gas after the primary combustion through the exhaust gas control valve 14 to increase the concentration of organic matter in the exhaust gas entering the second reactor 7; the control cabinet 1 collects the temperature of the exhaust gas discharged from the second reactor 7 through the second temperature sensor 3, and controls the temperature of the exhaust gas discharged from the second reactor 7 at 300°C-500°C by controlling the opening of the exhaust gas control valve 14.

[0038] In order to avoid equipment failure that may result in exhaust gas purification failing to meet standards, a pollutant analyzer 15 may be installed at the exhaust end of the second reactor 7. The control cabinet 1 collects the content of harmful substances such as carbon monoxide CO, nitrogen oxides NOx, and sulfides in the exhaust gas through the pollutant analyzer 15, so that corresponding measures can be taken in a timely manner when pollutant emissions fail to meet standards.

Claims

1. An exhaust gas combustion temperature adjustment system, characterized in that: It comprises: a control cabinet (1), a first temperature sensor (2), a second temperature sensor (3), a first oxygen regulating valve (4), a second oxygen regulating valve (5), a first reactor (6), a second reactor (7) and an exhaust gas control valve (14); The exhaust end of the first reactor (6) is connected to the intake end of the second reactor (7); The first temperature sensor (2) is installed at the exhaust end of the first reactor (6); The second temperature sensor (3) is installed at the exhaust end of the second reactor (7); The first oxygen regulating valve (4) is installed at the air inlet end of the first reactor (6); The second oxygen regulating valve (5) is installed at the air inlet end of the second reactor (7); The exhaust gas control valve (14) is installed at the air inlet end of the second reactor (7) and is electrically connected to the control cabinet (1) to control the concentration of organic matter discharged into the second reactor (7); The control cabinet (1) is electrically connected to the first temperature sensor (2) and the second temperature sensor (3) and is used to detect the exhaust gas temperature at the exhaust end of the first reactor (6) and the second reactor (7); The control cabinet (1) is electrically connected to the first oxygen regulating valve (4) and the second oxygen regulating valve (5) and is used to control the rate of oxygen flowing into the first reactor (6) and the second reactor (7).

2. The exhaust gas combustion temperature adjustment system according to claim 1, characterized in that: Also includes: A pressurized fan (8), a heat exchanger (9), a heater (10) and a heat recovery device (11), the waste gas to be treated is introduced into the air inlet end of the first reactor (6) through the pressurized fan (8), the heat exchanger (9) and the heater (10).

3. The exhaust gas combustion temperature adjustment system according to claim 2, characterized in that: The exhaust end of the first reactor (6) is connected to the heat exchanger (9) and the heat recovery device (11), and the exhaust gas discharged from the first reactor (6) is passed through the heat exchanger (9) and the heat recovery device (11) into the intake end of the second reactor (7); A heat regulating valve (12) is installed at the air inlet end of the heat recovery device (11), and a third temperature sensor (13) is installed at the air inlet end of the second reactor (7). The third temperature sensor (13) and the heat regulating valve (12) are both electrically connected to a control cabinet (1), and the control cabinet (1) controls the opening of the heat regulating valve (12) based on a signal from the third temperature sensor (13).

4. The exhaust gas combustion temperature adjustment system according to claim 2, characterized in that: The waste gas to be treated is introduced into the air inlet of the first reactor (6) through a pressure blower (8), a heat exchanger (9), a heater (10) and a waste gas control valve (14).

5. The exhaust gas combustion temperature adjustment system according to claim 1, characterized in that: A pollutant analyzer (15) is installed at the exhaust end of the second reactor (7), and the pollutant analyzer (15) is electrically connected to the control cabinet (1).

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