A high-concentration SO3-containing tail gas recovery device

Abstract

This utility model relates to a high-concentration SO3-containing tail gas recovery device, comprising an SO3 tail gas absorption tower equipped with packing material, a circulating pump, a cooler, and an SO3 buffer tank. The SO3 tail gas absorption tower has an absorbent inlet and an absorbent outlet on its upper and lower sides, respectively. The absorbent inlet is connected to a concentrated sulfuric acid inlet pipe, and the absorbent outlet is connected to the circulating pump. The circulating pump is connected to the cooler inlet, and the cooler outlet is connected to the absorbent return port at the top of the SO3 tail gas absorption tower and the SO3 buffer tank. The exhaust port at the top of the SO3 tail gas absorption tower is connected to a tail gas outlet pipe for outputting the tail gas to a tail gas treatment system. By utilizing the combination of cooled concentrated sulfuric acid and packing material, the SO3-containing tail gas is fully absorbed at low temperature, effectively improving the absorption effect and efficiency of SO3 in the tail gas. Simultaneously, the absorbent liquid provides temporary storage, facilitating subsequent packaging and reuse in the packaging area or other devices.

Description

Technical Field

[0001] This utility model relates to a device for recovering high-concentration SO3-containing exhaust gas. Background Technology

[0002] In the field of wet electronic chemical production, especially in the preparation of high-purity electronic-grade sulfuric acid and its subsequent tank storage and packaging, process tail gas is inevitably generated. The main component of this tail gas is high-concentration sulfur trioxide (SO3) gas. However, this type of sulfur trioxide tail gas has significant special characteristics and treatment difficulties, such as: (1) high moisture content: the tail gas usually carries a certain amount of water (H2O); (2) high dew point characteristics: due to the presence of moisture, the dew point temperature of the gas is significantly higher. These characteristics make it difficult for traditional sulfur trioxide recovery and acid production processes to directly recover and utilize the gas, because high moisture and high dew point will easily form sulfuric acid mist (H2SO4 mist) in traditional processes (such as conventional concentrated sulfuric acid absorption towers), which is difficult to capture, and cause serious equipment corrosion and pipeline blockage problems. Therefore, traditional processes cannot effectively realize the resource recovery of SO3 in this type of tail gas and use it to reproduce qualified acid products. Utility Model Content

[0003] This invention addresses the problems existing in the prior art by providing a high-concentration SO3-containing tail gas recovery device.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: a high-concentration SO3-containing tail gas recovery device, comprising an SO3 tail gas absorption tower, a circulating pump, a cooler, and an SO3 buffer tank. The SO3 tail gas absorption tower is internally packed with packing material. The SO3 tail gas absorption tower has an absorbent inlet and an absorbent outlet on the upper and lower sides of the packing material, respectively. The absorbent inlet is connected to a concentrated sulfuric acid inlet pipe. The absorbent outlet is connected to the inlet of the circulating pump. The outlet of the circulating pump is connected to the inlet of the cooler. The outlet of the cooler is connected to the absorbent return port at the top of the SO3 tail gas absorption tower and the SO3 buffer tank. A tail gas inlet pipe is connected between the packing material and the absorbent outlet of the SO3 tail gas absorption tower. The exhaust port at the top of the SO3 tail gas absorption tower is connected to a tail gas outlet pipe for outputting the tail gas to a tail gas treatment system.

[0005] Furthermore, there are two circulating pumps, which are connected in parallel.

[0006] Furthermore, the output end of the SO3 buffer tank is connected to an SO3 discharge pump.

[0007] Furthermore, the height of the packing material is ≥2m.

[0008] Furthermore, the packing material is Pall ring packing.

[0009] Compared with the prior art, the present invention has the following advantages: The present invention is reasonably designed and utilizes the combination of cooled concentrated sulfuric acid and packing material to fully absorb SO3-containing tail gas at low temperature, which effectively improves the absorption effect and efficiency of SO3 in the tail gas. At the same time, the absorbent liquid is temporarily stored in the SO3 buffer tank, which facilitates subsequent delivery to the packaging area or other devices for packaging and reuse. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model.

[0011] In the picture:

[0012] 1-SO3 tail gas absorption tower; 2-circulating pump; 3-cooler; 4-SO3 buffer tank; 5-SO3 discharge pump; 6-concentrated sulfuric acid inlet pipe; 7-tail gas inlet pipe; 8-packing; 9-tail gas outlet pipe. Detailed Implementation

[0013] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0014] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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.

[0015] like Figure 1As shown, this utility model discloses a high-concentration SO3-containing tail gas recovery device, comprising an SO3 tail gas absorption tower 1, a circulating pump 2, a cooler 3, and an SO3 buffer tank 4. The SO3 tail gas absorption tower 1 is internally filled with packing material 8. The absorption tower 1 has an absorbent inlet and an absorbent outlet on the upper and lower sides of the packing material 8, respectively. The absorbent inlet is connected to a concentrated sulfuric acid inlet pipe 6, which is used to input high-concentration concentrated sulfuric acid into the SO3 tail gas absorption tower 1, i.e., concentrated sulfuric acid is used as the absorbent. The absorbent outlet is connected to the inlet of the circulating pump 2, and the outlet of the circulating pump 2 is connected to the inlet of the cooler 3. The circulating pump 2 outputs the absorbent from the SO3 tail gas absorption tower 1 and then sends it to the cooler 3 for cooling. The output end of 3 is connected to the absorbent return port at the top of SO3 tail gas absorption tower 1 and SO3 buffer tank 4 respectively. The absorbent after cooling is sent into SO3 tail gas absorption tower 1 for recycling. After treatment, the absorbent can be sent into SO3 buffer tank 4 for temporary storage. The SO3 tail gas absorption tower 1 is connected to the packing 8 and the absorbent outlet with a tail gas input pipe 7. The tail gas input pipe 7 facilitates the input of tail gas from electronic grade sulfuric acid production, tank area and packaging workshop into SO3 tail gas absorption tower 1. The exhaust port at the top of SO3 tail gas absorption tower 1 is connected to a tail gas output pipe 9 for outputting tail gas to tail gas treatment system (not shown in the figure). Under the negative pressure of the tail gas treatment system, the tail gas in SO3 tail gas absorption tower is transported to tail gas treatment system through tail gas output pipe.

[0016] In this embodiment, the output end of the cooler 3 is connected to the absorbent return port at the top of the SO3 tail gas absorption tower and the SO3 buffer tank respectively through a three-way connector and pipeline. Control valves are provided on the pipeline connecting the output end of the cooler 3 to the absorbent return port at the top of the SO3 tail gas absorption tower and on the pipeline connecting the output end of the cooler 3 to the SO3 buffer tank to facilitate the control of the on / off state.

[0017] In this embodiment, there are two circulating pumps 2, which are connected in parallel.

[0018] In this embodiment, the output end of the SO3 buffer tank 4 is connected to an SO3 discharge pump 5, which then outputs the SO3 to the packaging area / other devices for packaging and reuse.

[0019] In this embodiment, the packing 8 is a bulk packing, which can be Pall ring packing. The height of the packing is ≥2m, which has low cost, good absorption effect and high absorption efficiency.

[0020] Detailed operation process:

[0021] Before the sulfuric acid workshop starts production, concentrated sulfuric acid is fed into SO3 tail gas absorption tower 1 through the concentrated sulfuric acid input pipe. The concentrated sulfuric acid serves as the absorbent. Circulating pump 2 outputs the concentrated sulfuric acid to cooler 3 for cooling, and then returns it to SO3 tail gas absorption tower 1, achieving a circulating cooling process for the concentrated sulfuric acid. After the sulfuric acid workshop starts production, the tail gas first enters SO3 tail gas absorption tower 1 for buffering. The buffered SO3 tail gas, under the negative pressure of the tail gas treatment system, rises through the packing material 8 (height ≥ 2m) inside SO3 tail gas absorption tower 1 before entering the tail gas treatment system. During this process, the concentrated sulfuric acid output by circulating pump 2 is cooled to a low temperature (≤ 15℃) by cooler 3. Then, under the action of the packing material inside the SO3 tail gas absorption tower, it undergoes thorough low-temperature absorption with the SO3 tail gas. The SO3 concentration in the absorbent continuously increases after continuous circulation and absorption. In SO3 tail gas absorption tower 1, when the SO3 concentration in the absorption liquid reaches a certain level, it is output to SO3 buffer tank 4 for temporary storage through circulation pump 2 and cooler 3, and then output to packaging area / other devices for packaging and reuse through SO3 discharge pump 5.

[0022] The advantages of this utility model are:

[0023] (1) Recover SO3 from exhaust gas as a byproduct to increase economic benefits;

[0024] (2) Reduce the quantity and frequency of acidic wastewater treatment generated in the exhaust gas treatment system by wastewater treatment equipment;

[0025] (3) Reduce the amount of water used for makeup water in the water scrubbing tower and alkali used for makeup alkali in the alkali scrubbing tower in the exhaust gas treatment system.

[0026] If this utility model discloses or relates to mutually fixedly connected parts or structural components, then, unless otherwise stated, a fixed connection can be understood as: a detachable fixed connection (e.g., using bolts or screws), or a non-detachable fixed connection (e.g., riveting, welding). Of course, mutually fixed connections can also be replaced by an integral structure (e.g., manufactured using a casting process) (except where it is obviously impossible to use an integral forming process).

[0027] In addition, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in this utility model above include states or shapes that are similar to, close to, or approximate with them.

[0028] Any component provided by this utility model can be assembled from multiple individual components, or it can be a single component manufactured by a one-piece molding process.

[0029] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A high concentration SO3 containing tail gas recovery unit, characterized by: The system includes an SO3 tail gas absorption tower, a circulating pump, a cooler, and an SO3 buffer tank. The SO3 tail gas absorption tower is filled with packing material. The absorption tower has an absorbent inlet and an absorbent outlet on the upper and lower sides of the packing material, respectively. The absorbent inlet is connected to a concentrated sulfuric acid inlet pipe. The absorbent outlet is connected to the inlet of the circulating pump, and the outlet of the circulating pump is connected to the inlet of the cooler. The outlet of the cooler is connected to the absorbent return port at the top of the SO3 tail gas absorption tower and the SO3 buffer tank. A tail gas inlet pipe is connected between the packing material and the absorbent outlet of the SO3 tail gas absorption tower. An exhaust port at the top of the SO3 tail gas absorption tower is connected to a tail gas outlet pipe for outputting tail gas to a tail gas treatment system.

2. The high concentration SO3 containing tail gas recovery unit of claim 1, wherein: There are two circulating pumps, which are connected in parallel.

3. The high concentration SO3 containing tail gas recovery unit of claim 1, wherein: The SO3 buffer tank is connected to an SO3 discharge pump at its output end.

4. The high concentration SO3 containing tail gas recovery unit of claim 1, wherein: The height of the packing material is ≥2m.

5. The high concentration SO3 containing off-gas recovery device according to claim 1, characterized in that: The packing material used is Pall ring packing.

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