An exhaust gas treatment system

Abstract

This utility model discloses a waste gas treatment system, including a pretreatment recovery unit. The inlet of the pretreatment recovery unit is connected to the outlet of the waste gas pipeline. The outlet of the pretreatment recovery unit is connected to the inlet of a cold recovery mechanism. The outlet of the cold recovery mechanism is connected to the inlet of a reduction absorption mechanism. The outlet of the reduction absorption mechanism is connected to the inlet of an exhaust stack via a centrifugal fan. This utility model can perform preliminary and deep recovery of chromic acid mist in waste gas, thereby effectively improving the recovery degree of chromic acid mist in waste gas. This reduces the amount of reducing agent required for chromic acid mist absorption and purification during subsequent purification, thus lowering the cost of reducing agent consumption.

Description

Technical Field

[0001] This utility model relates to the field of chromic acid mist treatment technology, and in particular to a waste gas treatment system. Background Technology

[0002] Currently, the main technology for treating chromic acid mist in the electroplating industry is the chromic mist recovery + reduction absorption purification process. The existing process route for chromic acid mist recovery uses mechanical filtration, collision interception and other principles to recover chromic acid mist. In the existing technology, the purification of chromic acid mist mainly uses a reducing agent to reduce highly toxic hexavalent chromium to low-toxic trivalent chromium, thereby reducing the environmental impact of hexavalent chromium and achieving the purpose of purification.

[0003] However, when chromic acid mist is recovered using mechanical filtration, collision interception and other principles, the recovery effect is poor and the efficiency is low, and the chromic acid mist cannot be fully recovered. Since most of the chromic acid mist is recovered, the amount of reducing agent required for chromic acid mist absorption and purification is reduced, thus reducing the cost of reducing agent consumption. Utility Model Content

[0004] (I) Purpose of the utility model

[0005] To address the technical problems existing in the background art, this utility model proposes a waste gas treatment system. This device can recover and deeply recover chromic acid mist in waste gas, thereby effectively improving the recovery degree of chromic acid mist in waste gas. As a result, in the subsequent purification of chromic acid mist, the amount of reducing agent required for chromic acid mist absorption and purification is reduced, thus reducing the cost of reducing agent consumption.

[0006] (II) Technical Solution

[0007] This utility model provides a waste gas treatment system, including a pretreatment recovery unit. The inlet of the pretreatment recovery unit is connected to the outlet of the waste gas pipeline. The outlet of the pretreatment recovery unit is connected to the inlet of a cold recovery mechanism. The outlet of the cold recovery mechanism is connected to the inlet of a reduction absorption mechanism. The outlet of the reduction absorption mechanism is connected to the inlet of an exhaust stack via a centrifugal fan.

[0008] Preferably, the cryogenic recovery mechanism includes a cryogenic recovery unit and a cooling water unit. The air inlet of the cryogenic recovery unit is connected to the air outlet of the pretreatment recovery unit, the air outlet of the cryogenic recovery unit is connected to the air inlet of the reduction absorption mechanism, the water outlet of the cooling water unit is connected to the water inlet of the cryogenic recovery unit, and the water inlet of the cooling water unit is connected to the water outlet of the cryogenic recovery unit.

[0009] Preferably, the cooling water unit includes a chiller and a cooling water tower. The cooling water tower is connected to the chiller via a circulating water pump. The inlet of the chiller is connected to the outlet of the cryogenic recovery unit. The outlet of the chiller is connected to the inlet of the cryogenic recovery unit via a chilled water pump.

[0010] Preferably, the reduction absorption mechanism includes an absorption tower, a circulating water tank, and a drug supply unit for supplying drugs to the circulating water pump. The air inlet of the absorption tower is connected to the air outlet of the cryogenic recovery unit. The air outlet of the absorption tower is connected to the water inlet of the exhaust stack via the centrifugal fan. The water outlet of the circulating water tank is connected to the water inlet of the absorption tower via the circulating pump. The water inlet of the circulating water tank is connected to both the water outlet of the absorption tower and the water supply end of the water supply mechanism. The drug supply end of the drug supply unit is connected to the circulating water tank.

[0011] Preferably, the drug supply unit includes a first dosing tank and a second dosing tank, the first dosing tank being connected to a circulating water tank via a first dosing pump, and the second dosing tank being connected to the circulating water tank via a second dosing pump.

[0012] Preferably, the circulating water tank is equipped with an OPR detector and a pH detector, and the circulating water tank is equipped with a first liquid level transfer device.

[0013] Preferably, the first dosing tank and the second dosing tank are each equipped with a second liquid level transfer device.

[0014] Compared with the prior art, the above-mentioned technical solution of this utility model has the following beneficial technical effects:

[0015] In this invention, the device can recover and deeply recover chromic acid mist in exhaust gas, thereby effectively improving the recovery degree of chromic acid mist in exhaust gas. This reduces the amount of reducing agent required for chromic acid mist absorption and purification during subsequent purification, thus reducing the cost of reducing agent consumption. Attached Figure Description

[0016] Figure 1 This is a flowchart of a waste gas treatment system proposed in this utility model.

[0017] Reference numerals: 1. Pretreatment recovery unit; 2. Cryogenic recovery unit; 3. Refrigeration unit; 4. Cooling tower; 5. Circulating water pump; 6. Chilled water pump; 7. Absorption tower; 8. Circulating water tank; 9. Circulating pump; 10. Centrifugal fan; 11. Exhaust stack; 12. First dosing tank; 13. Second dosing tank. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of this utility model. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of this utility model.

[0019] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," and "connected," etc., should be interpreted broadly. For example, "connected" can be a fixed connection, such as welding, riveting, or bonding; it can also be a detachable connection, such as threaded connection, keyed connection, or pin connection; or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; or it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0021] like Figure 1 As shown, the present invention proposes a waste gas treatment system, including a pretreatment recovery unit 1. The inlet end of the pretreatment recovery unit 1 is connected to the outlet end of the waste gas pipeline. The outlet end of the pretreatment recovery unit 1 is connected to the inlet end of the cold recovery mechanism. The outlet end of the cold recovery mechanism is connected to the inlet end of the reduction absorption mechanism. The outlet end of the reduction absorption mechanism is connected to the inlet end of the exhaust stack 11 through a centrifugal fan 10.

[0022] In this invention, during operation, the waste gas is first transported through a pipeline into the pretreatment recovery unit 1. Particulate matter and other impurities in the waste gas are intercepted and removed by the pretreatment recovery unit 1, which also performs preliminary recovery of chromic acid mist in the waste gas. After preliminary recovery, the waste gas continues into the cold recovery mechanism, where it undergoes condensation, thus efficiently separating the chromic acid mist. The waste gas then re-enters the reduction absorption mechanism, where it undergoes a thorough reaction to reduce and purify the residual chromic acid mist. Finally, the waste gas is discharged through the centrifugal fan 10 and the exhaust stack 11. This device can perform both initial and deep recovery of chromic acid mist in waste gas, effectively improving the recovery rate and reducing the amount of reducing agent required for subsequent chromic acid mist purification, thereby lowering the cost of reducing agent consumption.

[0023] In an optional embodiment, the cryogenic recovery mechanism includes a cryogenic recovery unit and a cooling water unit. The inlet of the cryogenic recovery unit 2 is connected to the outlet of the pretreatment recovery unit, and the outlet of the cryogenic recovery unit 2 is connected to the inlet of the reduction absorption unit. The outlet of the cooling water unit is connected to the inlet of the cryogenic recovery unit 2, and the inlet of the cooling water unit is connected to the outlet of the cryogenic recovery unit 2. The cooling water unit can produce cold water for the cryogenic recovery unit 2 to maintain its normal operation. The cryogenic recovery unit 2 can also effectively condense the exhaust gas, thereby completing the separation and recovery of chromic acid mist from emphysema.

[0024] In an optional embodiment, the cooling water unit includes a chiller 3 and a cooling tower 4. The cooling tower is connected to the chiller 3 via a circulating water pump 5. The inlet of the chiller 3 is connected to the outlet of the cryogenic recovery unit 2. The outlet of the chiller 3 is connected to the inlet of the cryogenic recovery unit 2 via a chilled water pump 6. The cooling tower 4 and the circulating water pump 5 can effectively cool the chiller 3, ensuring its normal operation. The chiller 3 can also effectively cool the hot water discharged from the cryogenic recovery unit 2, and then discharge it back into the cryogenic recovery unit 2 after cooling.

[0025] In an optional embodiment, the reduction absorption mechanism includes an absorption tower 7, a circulating water tank 8, and a drug supply unit for supplying chemicals to the circulating water pump 5. The air inlet of the absorption tower 7 is connected to the air outlet of the cryogenic recovery unit 2. The air outlet of the absorption tower 7 is connected to the water inlet of the exhaust stack 11 via the centrifugal fan 10. The water outlet of the circulating water tank 8 is connected to the water inlet of the absorption tower 7 via the circulating pump 9. The water inlet of the circulating water tank 8 is connected to both the water outlet of the absorption tower 7 and the water supply end of the water supply mechanism. The drug supply end of the drug supply unit is connected to the circulating water tank 8. The absorption tower 7 can effectively absorb chromic acid mist, attaching it to the water and allowing it to enter the circulating water tank 8. The drug supply unit can effectively reduce the chromic acid mist solution in the circulating water tank 8. After removing the chromic acid mist, the absorption tower 7 completes the purification of the waste gas, which can then be discharged through the centrifugal fan 10 and the exhaust stack 11.

[0026] In an optional embodiment, the dosing unit includes a first dosing tank 12 and a second dosing tank 13. The first dosing tank 12 is connected to the circulating water tank 8 via a first dosing pump, and the second dosing tank 13 is connected to the circulating water tank 8 via a second dosing pump. The first dosing tank 12 contains a (10%–20%) sodium metabisulfite solution, and the second dosing tank 13 contains a (10%–30%) NaOH solution. The two different solutions can effectively reduce the chromic acid mist entering the circulating water tank 8.

[0027] In an optional embodiment, the circulating water tank 8 is equipped with an OPR detector and a pH detector, and the circulating water tank 8 is equipped with a first liquid level transfer device. The detectors can effectively detect and monitor the real-time situation inside the circulating water tank 8.

[0028] In an optional embodiment, the first dosing tank 12 and the second dosing tank 13 are respectively provided with a second liquid level transmitter, which can effectively monitor the liquid level of different reducing agents in the first dosing tank 12 and the second dosing tank 13.

[0029] In one optional embodiment, the specific mechanisms mentioned above are all prior art and will not be described in detail in the patent.

[0030] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of this utility model and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of this utility model should be included within its protection scope. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. An exhaust gas treatment system characterized by, It includes a pretreatment and recovery unit, the air inlet of which is connected to the air outlet of the exhaust gas pipeline, the air outlet of which is connected to the air inlet of the cold recovery mechanism, the air outlet of which is connected to the air inlet of the reduction and absorption mechanism, and the air outlet of the reduction and absorption mechanism is connected to the air inlet of the exhaust stack through a centrifugal fan.

2. An exhaust treatment system according to claim 1, wherein, The cold recovery mechanism includes a cryogenic recovery unit and a cooling water unit. The air inlet of the cryogenic recovery unit is connected to the air outlet of the pretreatment recovery unit, and the air outlet of the cryogenic recovery unit is connected to the air inlet of the reduction absorption mechanism. The water outlet of the cooling water unit is connected to the water inlet of the cryogenic recovery unit, and the water inlet of the cooling water unit is connected to the water outlet of the cryogenic recovery unit.

3. An exhaust treatment system according to claim 2, wherein, The cooling water unit includes a chiller and a cooling water tower. The cooling water tower is connected to the chiller via a circulating water pump. The inlet of the chiller is connected to the outlet of the cryogenic recovery unit. The outlet of the chiller is connected to the inlet of the cryogenic recovery unit via a chilled water pump.

4. An exhaust treatment system according to claim 2, wherein, The reduction absorption mechanism includes an absorption tower, a circulating water tank, and a drug supply unit for supplying drugs to the circulating water pump. The air inlet of the absorption tower is connected to the air outlet of the cryogenic recovery unit. The air outlet of the absorption tower is connected to the water inlet of the exhaust stack via the centrifugal fan. The water outlet of the circulating water tank is connected to the water inlet of the absorption tower via the circulating pump. The water inlet of the circulating water tank is connected to both the water outlet of the absorption tower and the water supply end of the water supply mechanism. The drug supply end of the drug supply unit is connected to the circulating water tank.

5. An exhaust treatment system according to claim 4, wherein, The drug supply unit includes a first dosing tank and a second dosing tank. The first dosing tank is connected to the circulating water tank via a first dosing pump, and the second dosing tank is connected to the circulating water tank via a second dosing pump.

6. An exhaust treatment system according to claim 4, wherein, The circulating water tank is equipped with an OPR detector and a pH detector, and the circulating water tank is also equipped with a first liquid level transfer device.

7. An exhaust treatment system according to claim 5, wherein, The first and second dosing tanks are each equipped with a second liquid level transfer device.

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