Low-concentration organic waste gas treatment integrated device

Abstract

The utility model discloses a low-concentration organic waste gas treatment integrated device and belongs to the technical field of waste gas treatment. The device comprises a fan, a sewage inlet aeration tank and an RTO furnace, the fan is connected with a dry filter through a centrifugal fan and connected with the sewage inlet aeration tank through an air filter, and the sewage inlet aeration tank is connected with the RTO furnace. According to the low-concentration organic waste gas treatment device, after being effectively collected, the low-concentration organic waste gas is fed into the fan through the centrifugal fan to be used as fresh air, then enters the sewage aeration tank and enters the RTO furnace to be incinerated after being aerated, so that the treatment load of the RTO furnace is greatly reduced, and the fuel consumption of the RTO furnace is reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of waste gas treatment, and specifically relates to an integrated device for treating low-concentration organic waste gas. Background Art

[0002] At present, the main waste gas treatment measures in the fine chemical industry are RTO regenerative incinerators. The incineration method has the characteristics of high removal efficiency and continuous and stable emission compliance. When the RTO furnace is operating normally, the temperature in the furnace needs to be maintained at around 800°C. If the heat released by the combustion and oxidation of organic waste gas pollutants in the furnace body can maintain the furnace at around 800°C, the fuel consumed is relatively small. If not, a large amount of fuel needs to be burned to maintain the furnace temperature. Therefore, it is more appropriate to incinerate the organic waste gas generated by reaction, drying, and centrifugation in the production process of the chemical industry in the RTO furnace. This type of waste gas has a high concentration and can release a lot of heat during the RTO treatment process. However, the concentration of organic waste gas cannot be too high. If it enters the RTO too high, there will be safety risks. It needs to be adjusted to a suitable concentration with some low-concentration waste gas in the plant before entering the RTO furnace for incineration. Some low-concentration waste gas in the plant mainly comes from organic waste gas from reactor feeding, waste gas in sewage treatment, and waste gas from hazardous waste warehouses. Among them, the sewage aeration tank is an important link in the sewage treatment process. During normal operation, the waste gas comes from two parts: one is the waste gas volatilized from the sewage in the sewage tank itself, and the other is the waste gas generated by the fan aeration of the sewage. In the traditional process, the fan aeration air source is the fresh air around the fan. The fresh air is blown into the wastewater tank after passing through the fan, and then diffused out. Therefore, in addition to the waste gas generated by the production process of the entire plant, the waste gas from the hazardous waste warehouse and the waste gas from sewage treatment, a large amount of fresh air is added, so the design processing load of the RTO furnace is increased, and the investment in environmental protection equipment is increased accordingly. In addition, after the large amount of fresh air is added and aerated in the sewage tank, the diffused waste gas is all low-concentration waste gas, which enters the RTO for incineration, greatly increasing fuel consumption, thereby increasing the operating cost of environmental protection equipment.

[0003] Therefore, it is necessary to provide an integrated device for treating low-concentration organic waste gas. Utility Model Content

[0004] In view of the shortcomings of the prior art, the technical problem solved by the utility model is to provide an integrated device for treating low-concentration organic waste gas. The device effectively collects the low-concentration organic waste gas, and then sends it into the blower by a centrifugal fan to be used as fresh air. Then it enters the sewage aeration tank. After aeration is completed, it enters the RTO furnace for incineration, which greatly reduces the processing load of the RTO furnace and reduces the fuel consumption of the RTO furnace.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] An integrated device for treating low-concentration organic waste gas, comprising a fan, a sewage aeration tank and an RTO furnace. The fan is connected to a dry filter through a first centrifugal fan and to the sewage aeration tank through an air filter, and the sewage aeration tank is connected to the RTO furnace.

[0007] A switch butterfly valve is also provided between the fan and the first centrifugal fan.

[0008] A differential pressure gauge is connected in parallel to the dry filter.

[0009] An inlet flowmeter and a flame arrester are provided between the dry filter and the second centrifugal fan.

[0010] The inlet flowmeter is connected to the dry filter, and the flame arrester is connected to the second centrifugal fan.

[0011] An outlet flowmeter is provided between the air filter and the sewage aeration tank.

[0012] The first centrifugal fan is connected to the RTO furnace through a proportional regulating valve.

[0013] The fan is also connected to a pressure transmitter.

[0014] The dry filter is connected to a condensate drain port.

[0015] At least 3 fans are provided and are connected in series with each other.

[0016] Advantages of the present utility model:

[0017] (1) After effectively collecting the low-concentration organic waste gas, the present utility model sends it into the fan by a centrifugal fan, uses it as fresh air, then enters the sewage aeration tank, and enters the RTO furnace for incineration after aeration, greatly reducing the treatment load of the RTO furnace, reducing the fuel consumption of the RTO furnace, and being able to effectively reduce the total amount of waste gas in the whole plant, greatly reducing the investment cost and operation cost of the waste gas treatment equipment.

[0018] (2) The present utility model provides an exhaust gas bypass and a proportional regulating valve before the centrifugal fan sends the air into the fan inlet. In the case of fan failure or excessive air volume of low-concentration exhaust gas, the problem of exhaust gas leakage is effectively solved.

[0019] (3) The present utility model provides two access ports at the fan inlet. One path receives the low-concentration organic waste gas sent by the centrifugal fan, and the other path is open to the atmosphere. A pressure transmitter is provided on the pipeline open to the atmosphere, which can avoid insufficient air volume of the low-concentration organic waste gas resulting in insufficient aeration of the fan, and fresh air can be supplemented from the atmosphere.

[0020] (4) The flow monitoring at the inlet and outlet of this device and the pressure transmitters on the air pipe of the fan to the atmosphere provide double monitoring guarantees for all the low-concentration organic waste gas to enter the aeration system or the RTO furnace. Description of the Drawings

[0021] Figure 1 It is a schematic diagram of the overall structure of the present utility model;

[0022] Figure 2 It is a front elevation schematic diagram of the device of the present utility model.

[0023] In the figure: 1, flame arrester; 2, inlet flowmeter; 3, dry filter; 4, differential pressure gauge; 5, first centrifugal fan; 6, fan; 7, switch butterfly valve; 8, pressure transmitter; 9, air filter; 10, proportional regulating valve; 11, outlet flowmeter; 12, condensate drain port; 13, sewage aeration tank; 14, RTO furnace; 15, second centrifugal fan. Detailed Embodiment

[0024] Next, the technical solutions in the present utility model will be clearly and completely described in conjunction with the drawings in the present utility model. In addition, the forms of each structure described in the following embodiments are merely examples, and the present utility model is not limited to the structures described in the following embodiments. All other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present utility model.

[0025] Embodiment 1

[0026] As Figures 1-2As shown in the figure, the utility model provides an integrated device for treating low-concentration organic waste gas, which includes a fan 6, a sewage aeration tank 13 and an RTO furnace 14. The fan 6 is connected to a dry filter 3 through a first centrifugal fan 5 and to the sewage aeration tank 13 through an air filter 9, and the sewage aeration tank 13 is connected to the RTO furnace 14. After the low-concentration organic waste gas effectively collected throughout the plant is provided with the conveying power by a second centrifugal fan 15, it first enters the dry filter 3. The filtration air velocity of the filter bag is controlled at about 1.2 m / s. After filtration, it is sent into the inlet of the fan 6, pressurized by the fan 6 and then sent into the sewage tank aeration 13 through the air filter 9, and finally sent into the RTO furnace 14 for incineration by the waste gas collection measures of the aeration tank. At the same time, before the first centrifugal fan 5 sends the pretreated low-concentration organic waste gas into the inlet of the fan 6, an exhaust gas bypass pipeline is led out, and a proportional regulating valve 10 is arranged on the exhaust gas branch pipeline. In the case of the fan 6 undergoing fault repair, the on-off butterfly valve 7 before the inlet is closed, and the low-concentration organic waste gas is directly sent into the RTO main pipe through the exhaust gas bypass pipeline. Or in the case where the air volume of the first centrifugal fan 5 exceeds the intake air volume of the fan 6, part of the low-concentration organic waste gas is directly sent into the RTO main pipe through the exhaust gas bypass pipeline, and the flow rate of this part of the waste gas is controlled by the proportional regulating valve 10 on the branch pipeline, which serves as a standby emergency measure for this set of process equipment. The inlet of the fan 6 is divided into two paths. One path is the low-concentration organic waste gas sent by the first centrifugal fan 5, and the other path is directly to the atmosphere. In order to effectively judge whether all the low-concentration organic waste gas sent by the first centrifugal fan 5 enters the fan 6 to aerate the sewage tank, a pressure transmitter 8 is arranged on the pipeline to the atmosphere, and its pressure value should be negative, controlled at about -50 to 100 Pa(G). At the same time, flow monitoring is set on the main pipe for collecting low-concentration organic waste gas and the main pipe from the fan 6 to the sewage aeration tank 13, that is, an inlet flowmeter 2 and an outlet flowmeter 11. During operation, the inlet flow is controlled to be slightly less than the outlet flow.

[0027] There is also an on-off butterfly valve 7 between the fan 6 and the first centrifugal fan 5. When the fan 6 undergoes fault repair, the on-off butterfly valve 7 is closed to prevent the low-concentration organic waste gas from entering the fan 6. At this time, the on-off butterfly valve 7 is closed, so that the low-concentration organic waste gas directly enters the RTO furnace 14 for incineration through the exhaust gas bypass pipeline, and the flow rate is adjusted by the proportional regulating valve 10. The fan 6 is a Roots blower.

[0028] The air filter 9 is connected to the outlet of the fan 6. The low-concentration organic waste gas discharged from the first centrifugal fan 5 into the fan 6 passes through the air filter 9 again to filter dust and other particulate matters in the organic waste gas again, and then enters the sewage aeration tank 13 for aeration.

[0029] The dry filter 3 is connected in parallel with a differential pressure gauge 4, and a condensate drain port 12 is provided at the bottom for draining the sewage condensed from the low-concentration organic waste gas. At the same time, differential pressure gauges 4 are provided at the inlet and outlet of the dry filter 3 to evaluate whether the internal filter bags are blocked and then replaced. The low-concentration organic waste gas enters the dry filter 3, and the particulate matter in the waste gas is filtered and intercepted.

[0030] The dry filter 3 is connected in series with an inlet flowmeter 2, a flame arrester 1, and a second centrifugal fan 15. The low-concentration organic waste gas is collected by the second centrifugal fan 15 and then enters the dry filter 3. The flame arrester 1 and the inlet flowmeter 2 are arranged between the dry filter 3 and the second centrifugal fan 15. The flame arrester 1 is of the explosion suppression IIB type to prevent sparks from being generated due to classical friction and other reasons during the transportation of the organic waste gas, which poses a risk to the process safety of this device. The inlet flowmeter 2 is used to control the flow rate during operation to prevent the inlet flow rate from being greater than the outlet flow rate, resulting in incomplete treatment of the excessive waste gas concentration and increasing the treatment load and fuel consumption of the RTO furnace 14.

[0031] An outlet flowmeter 11 is provided between the air filter 9 and the sewage aeration tank 13. The flow rate of the organic waste gas passing through the air filter 9 and entering the sewage aeration tank 13 needs to be controlled by the outlet flowmeter 11 to make the outlet flow rate greater than the inlet flow rate, so that the RTO furnace can fully burn the waste gas.

[0032] The first centrifugal fan 5 is connected to the RTO furnace 14 through a proportional regulating valve 10 to form an exhaust gas bypass pipeline. In the case of maintenance of the fan 6, the inlet front butterfly valve 7 is closed, and the low-concentration organic waste gas is directly sent into the RTO main pipe through the exhaust gas bypass pipeline and then enters the RTO furnace 14 for combustion. The exhaust gas flow rate is controlled by the proportional regulating valve 10 on the branch pipeline, which is used as a standby emergency measure for this set of process equipment.

[0033] The fan 6 is also connected to a pressure transmitter 8. At least 3 fans 6 are provided and are connected in series. The inlet of the fan 6 is divided into two paths. One path is the low-concentration organic waste gas sent by the first centrifuge 5, and the other path is directly to the atmosphere. A pressure transmitter 8 is provided on the pipeline to the atmosphere. To effectively judge whether all the low-concentration organic waste gas of the first centrifugal fan 5 enters the fan 6 and then enters the sewage aeration tank 13 for aeration, its pressure value should be negative and controlled at about -50 to 100 Pa(G).

[0034] Usage method of the utility model: After the low-concentration organic waste gas effectively collected throughout the plant area is provided with conveying power by the second centrifugal fan 15, it first enters the dry filter 3. The filtration air velocity of the filter bag is controlled at about 1.2 m / s. After filtration, it is sent into the inlet of the fan 6, pressurized by the fan 6 and then sent into the sewage tank aeration 13 through the air filter 9, and finally sent into the RTO furnace 14 for incineration by the waste gas collection measures of the aeration tank. At the same time, before the first centrifugal fan 5 sends the pretreated low-concentration organic waste gas into the inlet of the fan 6, an exhaust gas bypass pipeline is led out, and a proportional regulating valve 10 is set on the exhaust gas branch pipeline. In the case of the fan 6 being under fault repair, the inlet butterfly valve 7 is closed, and the low-concentration organic waste gas is directly sent into the RTO main pipe through the exhaust gas bypass pipeline. Or when the air volume of the first centrifugal fan 5 exceeds the suction air volume of the fan 6, part of the low-concentration organic waste gas is directly sent into the RTO main pipe through the exhaust gas bypass pipeline. The flow rate of this part of the waste gas is controlled by the proportional regulating valve 10 on the branch pipeline, which serves as a standby emergency measure for this set of process equipment. The inlet of the fan 6 is divided into two paths. One path is the low-concentration organic waste gas sent by the first centrifugal fan 5, and the other path is directly to the atmosphere. To effectively judge whether all the low-concentration organic waste gas sent by the first centrifugal fan 5 enters the fan 6 to go to the sewage tank for aeration, a pressure transmitter 8 is set on the pipeline to the atmosphere, and its pressure value should be negative, controlled at about -50 to 100 Pa(G). At the same time, flow monitoring is set on the main pipe for collecting low-concentration organic waste gas and the main pipe for the fan 6 to go to the sewage aeration tank 13, that is, the inlet flowmeter 2 and the outlet flowmeter 11. During operation, the inlet flow is controlled to be slightly less than the outlet flow.

[0035] Example 2

[0036] According to the new low-concentration organic waste gas treatment process described in Example 1, taking the treatment of low-concentration organic waste gas in the hazardous waste storage and sludge pressure filtration room of a pharmaceutical factory as an example, there is a sewage treatment station in the plant area. The tank body that needs aeration is the nitrification reaction tank. The waste gas end treatment device of this factory is an RTO furnace, and the fuel used is natural gas. The specific example is as follows:

[0037] The low-concentration organic waste gas of the whole plant mainly comes from the hazardous waste warehouse and the sludge pressure filtration room. The main waste gas pollutants are acetone, methanol, and particulate matter, and the pollutant concentration ≤ 20 mg / m 3 , the designed treatment air volume is 3000 m 3 / h. The designed treatment air volume of the sewage treatment station in the plant area, that is, the nitrification reaction tank, is 5000 m 3 / h. Except for the above waste gas sources, the waste gas volume of the rest of the production workshops, etc., is designed to be 12000 m 3 / h. Before the transformation, the designed load of the RTO furnace of the whole plant is 20000 m 3 / h. The designed aeration air volume of the nitrification reaction tank in this plant area is 2500 - 3500 m 3 / h, after the low-concentration organic waste gas from the hazardous waste storage and sludge pressure filtration room is collected by the centrifugal fan 5, it is sent into the inlet of the fan 6 after passing through the flame arrester 1 and the dry filter 3 for pressure boosting, and then goes to the nitrification reaction tank for aeration. The on-off butterfly valve 7 and the fan 6 are controlled and interlocked with each other. When the fan 6 stops due to a fault, the on-off butterfly valve 7 is closed, and at the same time, the bypass branch proportional regulating valve 10 is fully opened. The proportional regulating valve 10 is also interlocked with the pressure transmitter 8 on the bypass branch of the inlet of the fan 6. The opening of the proportional regulating valve 10 is adjusted according to the magnitude of the pressure value detected by the pressure transmitter 8. When the detected pressure is positive, the proportional regulating valve 10 opens a certain opening. When the detected pressure is negative, fresh air is automatically supplemented into the atmosphere bypass of the inlet of the fan 6.

[0038] After the above transformation, the designed air volume of the low-concentration organic waste gas is 3000 m 3 / h is removed. At the same time, the air volume of the nitrification reaction tank remains unchanged, and the original operating air volume of the RTO incinerator is reduced from 20000 m 3 / h to 17000 m 3 / h. When the RTO incinerator maintains the furnace temperature at 800 °C and burns air, the required natural gas is 22 m 3 / per 10,000 m 3 of air. Since the concentration of the low-concentration organic waste gas is relatively low, calculated by air, the natural gas consumption of this factory can be saved by 6.6 m 3 . The RTO furnace operates for 7200 h per year, and 47520 m 3 of natural gas can be saved every year. The local natural gas is 3 yuan per m 3 on average, and 142560 yuan of natural gas can be saved every year.

Claims

1. An integrated device for treating low-concentration organic waste gas, characterized in that: The invention comprises a fan (6), a sewage aeration tank (13) and an RTO furnace (14); the fan (6) is connected to a dry filter (3) via a first centrifugal fan (5), and is connected to the sewage aeration tank (13) via an air filter (9); and the sewage aeration tank (13) is connected to the RTO furnace (14).

2. The integrated device for treating low-concentration organic waste gas according to claim 1, characterized in that: A switch butterfly valve (7) is also provided between the fan (6) and the first centrifugal fan (5).

3. The integrated device for treating low-concentration organic waste gas according to claim 1, characterized in that: The dry filter (3) is connected in parallel with a differential pressure gauge (4).

4. The integrated device for treating low-concentration organic waste gas according to claim 1, characterized in that: An inlet flow meter (2) and a flame arrester (1) are provided between the dry filter (3) and the second centrifugal fan (15).

5. The integrated device for treating low-concentration organic waste gas according to claim 4, characterized in that: The inlet flow meter (2) is connected to the dry filter (3), and the flame arrester (1) is connected to the second centrifugal fan (15).

6. The integrated device for treating low-concentration organic waste gas according to claim 1, characterized in that: An outlet flow meter (11) is provided between the air filter (9) and the sewage aeration tank (13).

7. The integrated device for treating low-concentration organic waste gas according to claim 1, characterized in that: The first centrifugal fan (5) is connected to the RTO furnace (14) via a proportional regulating valve (10).

8. The integrated device for treating low-concentration organic waste gas according to claim 1, characterized in that: The fan (6) is also connected to a pressure transmitter (8).

9. The integrated device for treating low-concentration organic waste gas according to claim 1, characterized in that: The dry filter (3) is connected to the condensate discharge port (12).

10. The integrated device for treating low-concentration organic waste gas according to claim 1, characterized in that: At least three fans (6) are provided and are connected in series.

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