A hydrofluoric acid tail gas recovery device

Abstract

This utility model relates to a recovery device, specifically a hydrofluoric acid tail gas recovery device, comprising a recovery tank equipped with a first cooling device. An absorption condenser is connected to the upper end of the recovery tank. The upper part of the recovery tank is connected to a workshop tail gas inlet pipe, an anhydrous hydrofluoric acid pipe, and a demineralized water pipe. The bottom of the recovery tank is connected to the input end of an absorption pump assembly via a first pipeline. The output end of the absorption pump assembly is connected to the upper part of the absorption condenser via a second pipeline. A branch pipeline connected to a hydrofluoric acid storage tank is provided on the second pipeline. This device can effectively improve the recovery and processing capacity, and the recovered hydrofluoric acid can be used as a by-product, increasing economic benefits.

Description

Technical Field

[0001] This utility model relates to a recycling device, specifically a hydrofluoric acid tail gas recycling device. Background Technology

[0002] The production of hydrofluoric acid generates a large amount of hydrofluoric acid tail gas. Hydrofluoric acid also volatilizes tail gas when stored at room temperature. Currently, the conventional treatment method for hydrofluoric acid tail gas is to collect the tail gas through a pipeline in the workshop. The collected tail gas is then directly discharged into the atmosphere after being treated in a water washing tower and an alkali washing tower. If the tail gas is directly discharged into the atmosphere, it will not only seriously pollute the environment, but also cause serious harm to animals and plants.

[0003] Common methods for treating exhaust gases include dilution, absorption, and adsorption. Dilution involves diluting the exhaust gas with air before high-altitude emission. This method is highly environmentally damaging and has been phased out. Absorption uses water or alkaline solutions to absorb and neutralize HF. This method is highly effective, and the absorption products can be recycled, effectively avoiding secondary pollution.

[0004] However, existing absorption methods are not ideal in terms of treatment efficiency and effect, and their exhaust gas treatment capacity needs to be improved. Adsorption methods use powdered or granular adsorbents (such as activated carbon) to adsorb fluorides. This method has a better purification effect, but it suffers from drawbacks such as large equipment size and high investment and operating costs. Utility Model Content

[0005] The purpose of this invention is to provide a hydrofluoric acid tail gas recovery device, which can effectively improve the recovery and processing capacity, and the recovered hydrofluoric acid can be used as a by-product to increase economic benefits.

[0006] The technical solution of this utility model is as follows: a hydrofluoric acid tail gas recovery device, including a recovery tank, the recovery tank is equipped with a first cooling device, the upper end of the recovery tank is connected to an absorption condenser, the upper part of the recovery tank is connected to the workshop tail gas input pipe, an anhydrous hydrofluoric acid pipe and a demineralized water pipe, the bottom of the recovery tank is connected to the input end of an absorption pump assembly via a first pipeline, the output end of the absorption pump assembly is connected to the upper part of the absorption condenser via a second pipeline, and a branch pipeline connected to a hydrofluoric acid storage tank is provided on the second pipeline.

[0007] Furthermore, the first cooling device includes a cooling pipe disposed in the recovery tank, one end of which is connected to a first low-temperature circulating water inlet pipe passing through the side wall of the recovery tank, and the other end of which is connected to a second low-temperature circulating water outlet pipe passing through the side wall of the recovery tank.

[0008] Furthermore, the side wall of the recovery tank is provided with a jacketed cavity, and a second low-temperature circulating water inlet pipe is connected to the bottom of one side of the jacketed cavity on the recovery tank, and a second low-temperature circulating water outlet pipe is connected to the upper part of the other side of the jacketed cavity on the recovery tank.

[0009] Furthermore, the lower part of the absorption condenser is connected to a third low-temperature circulating water inlet pipe, the upper part of the absorption condenser is connected to a third low-temperature circulating water outlet pipe, and the top of the absorption condenser is connected to the exhaust gas treatment system via a pipeline.

[0010] Furthermore, the absorption pump assembly consists of two sets of absorption pumps connected in parallel.

[0011] Furthermore, the top of the hydrofluoric acid storage tank is provided with a return pipe connected to the workshop exhaust gas input pipe.

[0012] Furthermore, the bottom of the hydrofluoric acid storage tank is connected to a discharge pump via a third pipeline, and the discharge pump is connected to the packaging system via a fourth pipeline.

[0013] Furthermore, the side wall of the hydrofluoric acid storage tank is provided with a jacketed cavity, the bottom of the hydrofluoric acid storage tank is connected to a fourth low-temperature circulating water inlet pipe, and the upper part of the hydrofluoric acid storage tank is connected to a fourth low-temperature circulating water outlet pipe.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] This device, through its pipeline design connecting the recovery tank, absorption condenser, absorption pump, and storage tank, is primarily designed to collect and recover hydrofluoric acid gas generated at each step of the hydrofluoric acid production process. The recovered hydrofluoric acid tail gas is then processed and formulated into industrial-grade hydrofluoric acid as a byproduct, increasing economic benefits, effectively enhancing recovery and treatment capacity, and reducing the quantity and frequency of fluoride-containing wastewater treatment in the tail gas system. It also reduces the amount of water used for makeup water in the water scrubbing tower and the amount of alkali used for makeup alkali in the alkali scrubbing tower within the tail gas system. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model;

[0017] In the diagram: 1-Recovery tank; 11-Workshop exhaust gas inlet pipe; 12-Anhydrous hydrofluoric acid pipe; 13-Desalinated water pipe; 14-First pipeline; 15-Cooling pipeline; 16-First low-temperature circulating water inlet pipe; 17-Second low-temperature circulating water outlet pipe; 18-Second low-temperature circulating water inlet pipe; 19-Second low-temperature circulating water outlet pipe; 2-Absorption condenser; 21-Second pipeline; 22-Branch pipeline; 23-Third low-temperature circulating water inlet pipe; 24-Third low-temperature circulating water outlet pipe; 3-Absorption pump; 4-Hydrofluoric acid storage tank; 41-Return pipe; 42-Third pipeline; 43-Fourth low-temperature circulating water inlet pipe; 44-Fourth low-temperature circulating water outlet pipe; 5-Discharge pump; 51-Fourth pipeline. Detailed Implementation

[0018] To make the above-mentioned features and advantages of this utility model more easily understood, specific embodiments are described below in conjunction with the accompanying drawings, but this utility model is not limited thereto.

[0019] refer to Figure 1

[0020] A hydrofluoric acid tail gas recovery device includes a recovery tank 1, which is equipped with a first cooling device. An absorption condenser 2 is connected to the upper end of the recovery tank 1. The upper part of the recovery tank 1 is connected to a workshop tail gas inlet pipe 11, an anhydrous hydrofluoric acid pipe 12, and a demineralized water pipe 13. The bottom of the recovery tank 1 is connected to the input end of an absorption pump assembly via a first pipeline 14. The output end of the absorption pump assembly is connected to the upper part of the absorption condenser 2 via a second pipeline 21. A branch pipeline 22 connected to a hydrofluoric acid storage tank 4 is provided on the second pipeline 21. The absorption condenser, recovery tank, and absorption pump are connected by pipelines to form a circulation system.

[0021] In this embodiment, in order to facilitate the cooling and temperature reduction of hydrofluoric acid tail gas and to perform low-temperature circulating treatment for the recovery tank, the first cooling device includes a cooling pipe 15 disposed in the recovery tank 1. One end of the cooling pipe 15 is connected to a first low-temperature circulating water inlet pipe 16 passing through the side wall of the recovery tank 1, and the other end of the cooling pipe 15 is connected to a second low-temperature circulating water outlet pipe 17 passing through the side wall of the recovery tank 1.

[0022] In this embodiment, the side wall of the recovery tank 1 is provided with a jacketed cavity. A second low-temperature circulating water inlet pipe 18 is connected to the bottom of one side of the jacketed cavity on the recovery tank 1, and a second low-temperature circulating water outlet pipe 19 is connected to the upper part of the other side of the jacketed cavity on the recovery tank 1.

[0023] In this embodiment, in order to perform low-temperature circulating treatment on the absorption condenser, the absorption condenser 2 is provided with a second cooling device. The second cooling device includes a third low-temperature circulating water inlet pipe 23 connected to the lower part of the absorption condenser 2, a third low-temperature circulating water outlet pipe 24 connected to the upper part of the absorption condenser 2, and the top of the absorption condenser is connected to the exhaust gas treatment system via a pipeline.

[0024] In this embodiment, the absorption pump assembly consists of two sets of absorption pumps 3 connected in parallel to improve absorption capacity.

[0025] In this embodiment, the top of the hydrofluoric acid storage tank 4 is provided with a return pipe 41 connected to the workshop exhaust gas input pipe 11, so that the hydrofluoric acid can be returned to the recovery tank for further recycling.

[0026] In this embodiment, the bottom of the hydrofluoric acid storage tank 4 is connected to a discharge pump 5 via a third pipeline 42. The discharge pump 5 is connected to the packaging system via a fourth pipeline 51, so that industrial-grade hydrofluoric acid can be discharged to the packaging system for packaging. The discharge pump is an industrial-grade hydrofluoric acid discharge pump.

[0027] In this embodiment, in order to perform cyclic cryogenic treatment on the hydrofluoric acid storage tank, the hydrofluoric acid storage tank 4 is provided with a third cooling device. The third cooling device includes a jacketed cavity disposed on the side wall of the hydrofluoric acid storage tank 4. The bottom of the jacketed cavity is connected to a fourth cryogenic circulating water inlet pipe 43, and the top of the jacketed cavity is connected to a fourth cryogenic circulating water outlet pipe 44.

[0028] Working Principle: Before starting production in the hydrofluoric acid workshop, demineralized water is injected into the hydrofluoric acid recovery tank 1, and the water is circulated and cooled. After the hydrofluoric acid production starts, the workshop exhaust gas first enters the hydrofluoric acid recovery tank 1 for buffering. The buffered hydrofluoric acid exhaust gas, under the negative pressure of the exhaust gas system, passes through the absorption condenser 2 and then enters the exhaust gas treatment system. During this process, the hydrofluoric acid exhaust gas and demineralized water undergo sufficient low-temperature absorption to form a hydrofluoric acid absorbent. The hydrofluoric acid absorbent forms an absorption cycle through the circulation recovery absorption pump 3 and the absorption condenser 2. The concentration of hydrofluoric acid after absorption continuously increases and is stored at low temperature in the hydrofluoric acid recovery tank 1. After the concentration in the hydrofluoric acid recovery tank 1 reaches a certain level, an appropriate amount of anhydrous hydrofluoric acid is added to adjust the concentration to achieve industrial-grade hydrofluoric acid concentration. During operation, the low-temperature circulating water inlet and outlet pipes of the recovery tank 1, absorption condenser 2, and hydrofluoric acid storage tank 4 continuously perform low-temperature circulating treatment.

[0029] After the hydrofluoric acid concentration in the hydrofluoric acid recovery tank 1 is adjusted to meet the industrial-grade concentration requirements, it is output to the industrial-grade hydrofluoric acid storage tank 4 for temporary storage, and then output to the packaging system for packaging through the industrial-grade hydrofluoric acid discharge pump 5.

[0030] If the terms "first" and "second" are used in the above description to define the components, those skilled in the art should know that the use of "first" and "second" is only for the convenience of distinguishing the components in the description. Unless otherwise stated, the above terms have no special meaning.

[0031] 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 or 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).

[0032] 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.

[0033] 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.

[0034] The above description is only a preferred embodiment of the present utility model. All equivalent changes and modifications made within the scope of the patent application of the present utility model shall be covered by the present utility model.

Claims

1. A hydrofluoric acid tail gas recovery apparatus comprising a recovery vessel, characterised in that, The recovery tank is equipped with a first cooling device. An absorption condenser is connected to the upper end of the recovery tank. The upper part of the recovery tank is connected to the workshop exhaust gas inlet pipe, anhydrous hydrofluoric acid pipe, and demineralized water pipe. The bottom of the recovery tank is connected to the input end of the absorption pump assembly via a first pipeline. The output end of the absorption pump assembly is connected to the upper part of the absorption condenser via a second pipeline. A branch pipeline connected to the hydrofluoric acid storage tank is provided on the second pipeline.

2. A hydrogen fluoride tail gas recovery unit according to claim 1, wherein, The first cooling device includes a cooling pipe installed inside the recovery tank. One end of the cooling pipe is connected to a first low-temperature circulating water inlet pipe that passes through the side wall of the recovery tank, and the other end of the cooling pipe is connected to a second low-temperature circulating water outlet pipe that passes through the side wall of the recovery tank.

3. A hydrogen fluoride tail gas recovery unit according to claim 2, wherein, The side wall of the recovery tank is provided with a jacketed cavity. A second low-temperature circulating water inlet pipe is connected to the bottom of one side of the jacketed cavity on the recovery tank, and a second low-temperature circulating water outlet pipe is connected to the upper part of the other side of the jacketed cavity on the recovery tank.

4. A hydrogen fluoride tail gas recovery apparatus according to claim 1, 2 or 3, characterised in that, The lower part of the absorption condenser is connected to a third low-temperature circulating water inlet pipe, the upper part of the absorption condenser is connected to a third low-temperature circulating water outlet pipe, and the top of the absorption condenser is connected to the exhaust gas treatment system via a pipeline.

5. A hydrogen fluoride tail gas recovery apparatus according to claim 1, 2 or 3, characterised in that, The absorption pump assembly consists of two sets of absorption pumps connected in parallel.

6. A hydrogen fluoride tail gas recovery unit according to claim 1, wherein, The top of the hydrofluoric acid storage tank is equipped with a return pipe that is connected to the workshop exhaust gas input pipe.

7. A hydrofluoric acid tail gas recovery device according to claim 1, 2, 3 or 6, characterized in that, The bottom of the hydrofluoric acid storage tank is connected to a discharge pump via a third pipeline, and the discharge pump is connected to the packaging system via a fourth pipeline.

8. A hydrogen fluoride tail gas recovery apparatus according to claim 1, 2, 3 or 6, wherein, The hydrofluoric acid storage tank has a jacketed cavity on its side wall. The hydrofluoric acid storage tank is located at the bottom of the jacketed cavity and connected to a fourth low-temperature circulating water inlet pipe. The hydrofluoric acid storage tank is located at the top of the jacketed cavity and connected to a fourth low-temperature circulating water outlet pipe.

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