Electronic-grade hydrofluoric acid production waste acid recovery device

Abstract

A waste acid recovery device for electronic-grade hydrofluoric acid production comprises a first-stage rectifying tower kettle and a second-stage rectifying tower kettle, a waste acid discharge port of the first-stage rectifying tower kettle is connected with a first waste acid tank through a pipeline, and the first waste acid tank is connected with a first sampler and a first delivery pump through pipelines. A waste acid discharge port of the second-stage rectifying tower kettle is connected with a second waste acid tank, the second waste acid tank is respectively connected with a second sampler and a second delivery pump through pipelines, and liquid outlets of the first delivery pump and the second delivery pump are respectively connected with an industrial-grade hydrofluoric acid preparation pipeline and a preprocessor through pipelines; one side of the pretreater is connected with a filter through a pipeline, one side of the filter is connected with a rectification pipeline, the waste acid discharged at different stages is recovered to different storage tanks, so that the pollution of raw materials can be reduced, and effective contrastive analysis can be carried out; the standard waste acid is further purified through impurity removal, filtration and the like before entering a rectification system, so that the influence on product quality fluctuation is prevented; after waste acid recovery, hydrogen fluoride unit consumption of the device can be reduced by about 10%.

Description

Technical Field

[0001] The utility model relates to a waste acid recovery device, in particular to a waste acid recovery device for electronic grade hydrofluoric acid production. Background Art

[0002] The raw materials for producing ultra-high-purity electronic-grade hydrofluoric acid are primarily high-purity anhydrous hydrogen fluoride and ultrapure water. The production of high-purity anhydrous hydrogen fluoride requires distillation and purification, which produces a large amount of low-quality anhydrous hydrogen fluoride (waste acid). Currently, waste acid is primarily used to produce low-grade products such as industrial-grade hydrofluoric acid or photovoltaic-grade hydrofluoric acid, resulting in high hydrogen fluoride consumption and increased costs. Utility Model Content

[0003] In view of the above situation, in order to overcome the defects of the prior art, the utility model provides a waste acid recovery device for the production of electronic-grade hydrofluoric acid, which effectively solves the problem that the current waste acid treatment method is mainly used to prepare low-grade products such as industrial-grade hydrofluoric acid or photovoltaic-grade hydrofluoric acid, resulting in high hydrogen fluoride consumption and increased costs.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: the present invention includes a first-stage distillation tower kettle, a second-stage distillation tower kettle, a first waste acid tank, a first sampler, a first delivery pump, a second waste acid tank, a second sampler, a second delivery pump, an industrial-grade hydrofluoric acid preparation pipeline, a preprocessor, a filter and a distillation pipeline. The waste acid discharge port of the first-stage distillation tower kettle is connected to the first waste acid tank through a pipeline, the first waste acid tank is respectively connected to the first sampler and the first delivery pump through pipelines, the waste acid discharge port of the second-stage distillation tower kettle is connected to the second waste acid tank, the second waste acid tank is respectively connected to the second sampler and the second delivery pump through pipelines, the liquid outlets of the first delivery pump and the second delivery pump are respectively connected to the industrial-grade hydrofluoric acid preparation pipeline and the preprocessor through pipelines, one side of the preprocessor is connected to the filter through a pipeline, and one side of the filter is connected to the distillation pipeline.

[0005] Preferably, the preprocessor is a DN200 preprocessor.

[0006] Preferably, the first sampler and the second sampler are both sealed samplers made of PFA material.

[0007] Preferably, both the first waste acid tank and the second waste acid tank are equipped with liquid level gauges.

[0008] Preferably, the filter is a filter with an accuracy of 10 μm.

[0009] Preferably, solenoid valves are installed on the industrial-grade hydrofluoric acid preparation pipeline and the pipeline between the preprocessor and the first delivery pump and the second delivery pump.

[0010] Beneficial effect: When the utility model is used, the waste acid generated in the first stage distillation tower kettle is transported to the first waste acid tank through the pipeline, and the waste acid generated in the second stage distillation tower kettle is transported to the second waste acid tank through the pipeline. It is observed by the liquid level meter that when the liquid levels in the first waste acid tank and the second waste acid tank reach 30%, the first sampler and the second sampler are used to sample the waste acid liquid in the first waste acid tank and the second waste acid tank respectively. After sampling, the samples are sent to the inspector for inspection. If the indicators meet the requirements of the GB7746-2011 quality standard, the industrial-grade hydrofluoric acid preparation pipeline is closed, and the first delivery pump or the second delivery pump is controlled to work by an external switch. The first delivery pump or the second delivery pump works to deliver the qualified waste acid liquid to the preprocessor, i.e., the DN200 type preprocessor for impurity removal treatment. After treatment, it is filtered through a filter to become a liquid with an accuracy of 10um, and finally delivered to the distillation system for reuse. If the indicators do not meet the requirements of GB The 7746-2011 quality standard requires that when the preprocessor pipeline is closed, the first or second delivery pump is controlled by an external switch to operate, and the first or second delivery pump operates to deliver qualified waste acid liquid to the industrial-grade hydrofluoric acid production pipeline to produce industrial-grade hydrofluoric acid. This utility model has a novel structure and ingenious design. The waste acid discharged at different stages is recycled into different storage tanks, reducing raw material contamination and enabling effective comparative analysis. Before entering the distillation system, the qualified waste acid undergoes further purification through impurity removal and filtration to prevent fluctuations in product quality. The recycled waste acid can reduce the unit hydrogen fluoride consumption of the device by approximately 10%. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0012] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0013] Numbers in the figure: 1. First-stage distillation tower kettle; 2. Second-stage distillation tower kettle; 3. First waste acid tank; 4. First sampler; 5. First transfer pump; 6. Second waste acid tank; 7. Second sampler; 8. Second transfer pump; 9. Industrial-grade hydrofluoric acid preparation pipeline; 10. Pretreatment unit; 11. Filter; 12. Distillation pipeline. DETAILED DESCRIPTION

[0014] The following is combined with Figure 1 The specific implementation methods of the present utility model are further described in detail.

[0015] Embodiment 1, by Figure 1The utility model provides an electronic grade hydrofluoric acid production waste acid recovery device, comprising a first stage distillation tower reactor 1, a second stage distillation tower reactor 2, a first waste acid tank 3, a first sampler 4, a first delivery pump 5, a second waste acid tank 6, a second sampler 7, a second delivery pump 8, an industrial grade hydrofluoric acid preparation pipeline 9, a pretreatment unit 10, a filter 11 and a distillation pipeline 12, the waste acid discharge port of the first stage distillation tower reactor 1 is connected to the first waste acid tank 3 through a pipeline, and the first waste acid tank 3 is respectively connected to the first sampler 4 and The first delivery pump 5 and the waste acid discharge port of the second-stage distillation tower bottom 2 are connected to the second waste acid tank 6, and the second waste acid tank 6 is respectively connected to the second sampler 7 and the second delivery pump 8 through pipelines. The liquid outlets of the first delivery pump 5 and the second delivery pump 8 are respectively connected to the industrial-grade hydrofluoric acid preparation pipeline 9 and the preprocessor 10 through pipelines. One side of the preprocessor 10 is connected to the filter 11 through a pipeline, and one side of the filter 11 is connected to the distillation pipeline 12. The first delivery pump 5 and the second delivery pump 8 are respectively electrically connected to the external control switch.

[0016] The pre-processor 10 adopts a DN200 type pre-processor, which is convenient for pre-processing qualified waste acid.

[0017] The first sampler 4 and the second sampler 7 are both sealed samplers made of PFA material, which facilitates sealed sampling.

[0018] Liquid level gauges are installed on both the first waste acid tank 3 and the second waste acid tank 6 to facilitate observation of the liquid levels of the first waste acid tank 3 and the second waste acid tank 6 .

[0019] The filter 11 adopts a filter with an accuracy of 10 μm, which is convenient for filtering qualified waste acid.

[0020] Solenoid valves are installed on the industrial-grade hydrofluoric acid preparation pipeline 9 and the pipelines between the pre-processor 10 and the first delivery pump 5 and the second delivery pump 8 to facilitate the control of the pipelines.

[0021] Working principle: When the present invention is used, the waste acid produced by the first stage distillation tower kettle 1 is transported to the first waste acid tank 3 through a pipeline, and the waste acid produced by the second stage distillation tower kettle 2 is transported to the second waste acid tank 6 through a pipeline. It is observed by a liquid level gauge that when the liquid levels in the first waste acid tank 3 and the second waste acid tank 6 reach 30%, the first sampler 4 and the second sampler 7 are used to sample the waste acid liquid in the first waste acid tank 3 and the second waste acid tank 6 respectively. After sampling, the waste acid liquid is sent to the inspector for inspection. If the indicators meet the requirements of the GB 7746-2011 quality standard, the industrial-grade hydrofluoric acid preparation pipeline 9 is closed, and the first delivery pump 5 or the second delivery pump 8 is controlled to work by an external switch. The first delivery pump 5 or the second delivery pump 8 works to deliver the qualified waste acid liquid to the preprocessor 10, i.e., the DN200 type preprocessor, for impurity removal treatment. After treatment, it is filtered into a liquid with an accuracy of 10um through the filter 11, and finally delivered to the distillation system for reuse. If the indicators do not meet the requirements of GB According to the 7746-2011 quality standard, when the pre-processor 10 pipeline is closed, the first delivery pump 5 or the second delivery pump 8 is controlled by an external switch to work, and the first delivery pump 5 or the second delivery pump 8 works to deliver the qualified waste acid liquid to the industrial-grade hydrofluoric acid preparation pipeline 9 to prepare industrial-grade hydrofluoric acid.

[0022] Beneficial effects: The utility model has a novel structure and an ingenious concept. Waste acid discharged at different stages is recycled into different storage tanks, which can reduce raw material pollution and conduct effective comparative analysis. The qualified waste acid is further purified by impurity removal and filtration before entering the distillation system to prevent fluctuations in product quality. After the waste acid is recycled, the unit consumption of hydrogen fluoride in the device can be reduced by about 10%.

[0023] Through the use of wires by those skilled in the art, all electrical components in this case are connected to their corresponding power supplies, and appropriate controllers and encoders should be selected according to actual conditions to meet control requirements. The specific connection and control sequence should refer to the following working principle, in which the electrical components are electrically connected in sequence. The detailed connection means are well-known technologies in this field. The following mainly introduces the working principle and process, and no longer explains the electrical control.

[0024] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A device for recovering waste acid from the production of electronic-grade hydrofluoric acid, comprising a first-stage distillation tower still (1) and a second-stage distillation tower still (2), characterized in that: The waste acid discharge port of the first-stage distillation tower kettle (1) is connected to a first waste acid tank (3) through a pipeline, and the first waste acid tank (3) is respectively connected to a first sampler (4) and a first delivery pump (5) through pipelines. The waste acid discharge port of the second-stage distillation tower kettle (2) is connected to a second waste acid tank (6), and the second waste acid tank (6) is respectively connected to a second sampler (7) and a second delivery pump (8) through pipelines. The liquid outlets of the first delivery pump (5) and the second delivery pump (8) are respectively connected to an industrial-grade hydrofluoric acid preparation pipeline (9) and a preprocessor (10) through pipelines. One side of the preprocessor (10) is connected to a filter (11) through a pipeline, and one side of the filter (11) is connected to a distillation pipeline (12).

2. The electronic-grade hydrofluoric acid production waste acid recovery device according to claim 1, characterized in that: The preprocessor (10) adopts a DN200 type preprocessor.

3. The electronic-grade hydrofluoric acid production waste acid recovery device according to claim 1, characterized in that: The first sampler (4) and the second sampler (7) are both sealed samplers made of PFA material.

4. The electronic-grade hydrofluoric acid production waste acid recovery device according to claim 1, characterized in that: Liquid level gauges are installed on both the first waste acid tank (3) and the second waste acid tank (6).

5. The electronic-grade hydrofluoric acid production waste acid recovery device according to claim 1, characterized in that: The filter (11) is a filter with a precision of 10 μm.

6. The electronic-grade hydrofluoric acid production waste acid recovery device according to claim 1, characterized in that: Solenoid valves are installed on the industrial-grade hydrofluoric acid preparation pipeline (9) and the pipelines between the pre-processor (10) and the first delivery pump (5) and the second delivery pump (8).

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