Electronic grade dilute sulphuric acid preparation equipment

Abstract

The utility model provides electronic grade dilute sulphuric acid preparation equipment which comprises an ultrapure water storage tank, a concentrated sulphuric acid storage tank, a dilution tank, a heat exchanger, a dilute sulphuric acid storage tank and a filtering system, and an ultrapure water spraying device, a concentrated sulphuric acid spraying device, a concentration meter and a temperature control system are arranged in the dilution tank. Concentrated sulfuric acid and ultrapure water are mixed through the concentrated sulfuric acid spraying device and the ultrapure water spraying device, and the situation that a large amount of heat is intensively released is avoided; dilute sulfuric acid is cooled through the heat exchanger, the cooling rate is increased, the dilution efficiency is improved, the dilute sulfuric acid is deeply filtered through the filtering system, small particles and impurities in the solution are effectively removed, and therefore the granularity quality of the sulfuric acid is remarkably improved; according to the equipment, high-purity, stable and automatic production of dilute sulphuric acid is realized through an accurate metering system, an efficient circulating system, an accurate temperature control system and a reliable purification system, and the requirements of the electronic industry on high-purity dilute sulphuric acid are met.

Description

Technical Field

[0001] The utility model belongs to the field of chemical engineering, and specifically relates to an electronic grade dilute sulfuric acid preparation device. Background Art

[0002] Dilute sulfuric acid, as an important chemical raw material, is widely used in the electronics industry. Its preparation method directly impacts the quality and performance of electronic products. In semiconductor manufacturing, dilute sulfuric acid is used to clean and etch wafers, and its purity and stability are directly related to wafer yield. In photovoltaic cell production, dilute sulfuric acid is used to etch and clean silicon wafers, crucially impacting cell conversion efficiency. And in flat-panel display manufacturing, dilute sulfuric acid is used to clean glass substrates, and its quality directly impacts the display's clarity and lifespan.

[0003] Existing methods for preparing dilute sulfuric acid typically involve manual dilution and simple mixing. These methods suffer from the following issues: The control precision during the preparation process is low, making it difficult to meet the electronics industry's stringent requirements for dilute sulfuric acid purity. The operation is complex, requiring extensive manual intervention, increasing operating costs and the risk of human error. Furthermore, imperfect purification systems make it difficult to remove metal ions and other impurities from the sulfuric acid, impacting the quality of the final product. Therefore, the electronics industry urgently needs automated equipment for preparing dilute sulfuric acid that achieves high purity, high stability, ease of operation, and cost-effectiveness. Utility Model Content

[0004] In order to address the deficiencies of the prior art, the main purpose of the utility model is to provide an electronic-grade dilute sulfuric acid preparation device, which achieves high purity, stability and automated production of dilute sulfuric acid through a precise metering system, an efficient circulation system, a precise temperature control system and a reliable purification system.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] An electronic grade dilute sulfuric acid preparation device, comprising an ultrapure water storage tank, a concentrated sulfuric acid storage tank, a dilution tank, a heat exchanger and a dilute sulfuric acid storage tank.

[0007] The ultrapure water storage tank is connected to the dilution tank through a first pipe, one end of the first pipe connected to the dilution tank is located in the middle of the dilution tank, and the end of the first pipe connected to the dilution tank is provided with an ultrapure water spray device;

[0008] The concentrated sulfuric acid storage tank is connected to the dilution tank through a second pipe, one end of the second pipe connected to the dilution tank is located at the top of the dilution tank, and the other end of the second pipe connected to the dilution tank is provided with a concentrated sulfuric acid spray device;

[0009] The heat exchanger includes a first heat exchanger and a second heat exchanger, wherein the first heat exchanger is wrapped around the outside of the dilution tank to reduce the heat generated during the dilution process and prevent thermal corrosion;

[0010] The second heat exchanger is arranged outside the dilution tank and connected to the dilution tank through a third pipe, and is used to cool the dilute sulfuric acid;

[0011] The dilute sulfuric acid storage tank is connected to the heat exchanger through a fourth pipeline and is used to store cooled dilute sulfuric acid.

[0012] Furthermore, the equipment also includes a filtering system, which is arranged outside the dilute sulfuric acid storage tank.

[0013] Furthermore, the filtration system is a three-stage filtration system, which deeply filters the dilute sulfuric acid in the storage tank, further improving the particle size quality of the dilute sulfuric acid and ensuring that the product meets electronic grade standards; the filtered dilute sulfuric acid is transported to the packaging container to complete the preparation and packaging of the product.

[0014] Furthermore, the dilution tank is provided with a temperature control system for monitoring and adjusting the temperature during the dilution process to ensure the stability and safety of the dilution process.

[0015] Furthermore, the ultrapure water spraying devices are symmetrically located at the middle and upper parts of the side walls of the dilution tank, and are used to contact with the atomized concentrated sulfuric acid droplets for dilution.

[0016] Furthermore, there are at least two ultrapure water spraying devices.

[0017] Furthermore, the concentrated sulfuric acid spraying device is arranged at the top middle position of the dilution tank, and is used to atomize the concentrated sulfuric acid and spray it evenly into the ultrapure water.

[0018] Furthermore, a first concentration meter is provided in the concentrated sulfuric acid storage tank for real-time monitoring of the concentration of concentrated sulfuric acid; and a flow meter and a control valve are provided on the second pipeline for accurately measuring and adjusting the flow of concentrated sulfuric acid.

[0019] Furthermore, a second concentration meter is provided at the bottom of the dilution tank for monitoring the concentration of dilute sulfuric acid and extracting it after reaching a set value; a dilute sulfuric acid outlet is provided at the lower middle part of the side wall of the dilution tank for circulating the cooled dilute sulfuric acid back to the dilution tank.

[0020] Furthermore, a circulation pump is provided on the third pipeline, and the circulation pump is connected to the bottom of the dilution tank through a pipeline to promote mixing of concentrated sulfuric acid and ultrapure water.

[0021] This utility model provides equipment for preparing electronic-grade dilute sulfuric acid. The equipment utilizes a concentrated sulfuric acid spray device and an ultrapure water spray device to mix concentrated sulfuric acid and ultrapure water, thus avoiding the concentrated release of large amounts of heat. The dilute sulfuric acid is cooled twice via a heat exchanger, accelerating the cooling rate and improving dilution efficiency. Through a precise metering system, an efficient circulation system, a precise temperature control system, and a reliable purification system, the equipment achieves high-purity, stable, and automated production of dilute sulfuric acid, meeting the electronics industry's demand for high-purity dilute sulfuric acid. It also improves the preparation efficiency of electronic-grade dilute sulfuric acid, reduces operating costs, and ensures operational safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below with reference to the accompanying drawings:

[0023] Figure 1 It is a schematic diagram of the electronic grade dilute sulfuric acid preparation equipment of the utility model;

[0024] In the figure: 1 ultrapure water storage tank, 2 acid storage tank, 3 flow meter and control valve, 4 first concentration meter, 5 ultrapure water spray device, 6 dilution tank, 7 concentrated sulfuric acid spray device, 8 first heat exchanger, 9 second concentration meter, 10 dilute sulfuric acid outlet, 11 second heat exchanger, 12 dilute sulfuric acid storage tank, 13 tertiary filtration system, 14 packaging product, 15 first diaphragm pump, 16 second diaphragm pump, 17 circulation pump, 18 third diaphragm pump, 19 fourth diaphragm pump. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to the accompanying drawings:

[0026] like Figure 1 As shown, an electronic grade dilute sulfuric acid preparation equipment includes a water storage tank, a concentrated sulfuric acid storage tank, a dilution tank, a heat exchanger and a dilute sulfuric acid storage tank, the ultrapure water storage tank 1 is connected to the dilution tank 6 through a first pipe, the end of the first pipe connected to the dilution tank 6 is located in the middle of the dilution tank 6, and the end of the first pipe connected to the dilution tank 6 is provided with an ultrapure water spray device 5; the concentrated sulfuric acid storage tank 2 is connected to the dilution tank 6 through a second pipe, and the end of the second pipe connected to the dilution tank is provided with a concentrated sulfuric acid spray device 7, the end of the second pipe connected to the dilution tank 6 is located in the middle of the top of the dilution tank 6, for atomizing the concentrated sulfuric acid and evenly spraying it into the ultrapure water; the heat exchanger includes a first heat exchanger 8 and a second heat exchanger 11, the first heat exchanger 8 is wrapped around the outside of the dilution tank 6, for reducing the heat generated during the dilution process and preventing thermal corrosion; the second heat exchanger 11 is arranged outside the dilution tank 6, connected to the dilution tank through a third pipe, for cooling the diluted sulfuric acid; the dilute sulfuric acid storage tank 12 is connected to the heat exchanger 11 through a fourth pipe for storing cooled dilute sulfuric acid.

[0027] In a specific embodiment, the equipment also includes a filtration system 13, which is arranged outside the dilute sulfuric acid storage tank; the filtration system is a three-stage filtration system 13, and the three-stage filtration system 13 is composed of multiple precision filters. The size selection range of the filter element is 0.1μm-0.01μm, and the dilute sulfuric acid in the storage tank 12 is deeply filtered. The dilute sulfuric acid is deeply filtered to effectively remove tiny particles and impurities in the solution, thereby significantly improving the particle size quality of the sulfuric acid and ensuring that it meets the high-standard semiconductor application requirements; after circulating filtration, until the sulfuric acid reaches the specified purity standard, it is transported to the packaging container to complete the preparation and packaging of the product.

[0028] In a specific embodiment, the dilution tank is provided with a temperature control system for monitoring and adjusting the temperature during the dilution process to ensure the stability and safety of the dilution process.

[0029] In a specific embodiment, a first diaphragm pump 15 is provided on the first pipeline for transporting ultrapure water to the ultrapure water spraying device 5 .

[0030] In a specific embodiment, in the ultrapure water storage tank 1, the tank shell is made of 316L stainless steel and polypropylene, which has sufficient corrosion resistance to ensure that no metal precipitation occurs, thereby guaranteeing the quality of ultrapure water; the resistivity of the ultrapure water is above 18.2 MΩ·cm, the total organic carbon (TOC) content is less than 5 ppb, and the metal ion content is less than 1 ppb.

[0031] In a specific embodiment, the ultrapure water spray devices 5 are symmetrically located at the middle and upper parts of the side walls of the dilution tank, and are used to contact with the atomized concentrated sulfuric acid droplets for dilution; there are at least two ultrapure water spray devices 5.

[0032] In a specific embodiment, in the concentrated sulfuric acid storage tank 2, the storage tank shell is made of 316L stainless steel, and the shell lining is high-purity PFA material to provide sufficient corrosion resistance to ensure that no metal precipitation occurs during storage. A first concentration meter 4 is provided in the concentrated sulfuric acid storage tank 2 for real-time monitoring of the concentration of concentrated sulfuric acid; a flow meter and a control valve 3 are provided on the second pipeline for accurately measuring and adjusting the flow of concentrated sulfuric acid. The above-mentioned concentration meter 4, flow meter and control valve 3 ensure accurate control of the extraction ratio and concentration of concentrated sulfuric acid to meet the preparation requirements of electronic grade dilute sulfuric acid. The ratio of concentrated sulfuric acid extraction is adjusted according to the required concentration to achieve the purpose of accurately controlling the concentration of dilute sulfuric acid. A second diaphragm pump 16 is also provided on the second pipeline for transporting concentrated sulfuric acid to the concentrated sulfuric acid spray device 7.

[0033] In a specific embodiment, a second concentration meter 9 is provided at the bottom of the dilution tank 6 for monitoring the sulfuric acid concentration and extracting it after reaching a set value; a dilute sulfuric acid outlet 10 is provided at the lower middle part of the side wall of the dilution tank for circulating the dilute sulfuric acid cooled by the heat exchanger 11 back to the dilution tank.

[0034] In a specific embodiment, a circulation pump 17 is provided on the third pipeline, and the circulation pump is connected to the bottom of the dilution tank to promote mixing of concentrated sulfuric acid and ultrapure water.

[0035] In a specific embodiment, a third diaphragm pump 18 is provided on the fourth pipeline for transporting the qualified dilute sulfuric acid to the dilute sulfuric acid storage tank 12 .

[0036] In this embodiment, the dilute sulfuric acid in the dilute sulfuric acid storage tank is fed into the tertiary filtration system 13 via a fourth diaphragm pump 19. The filtration system 13 then filters the dilute sulfuric acid until it reaches the specified purity standard. The qualified dilute sulfuric acid is then delivered to the packaging line. The dilute sulfuric acid on the packaging line is then filled into specialized packaging products 14. After being securely sealed and labeled, the product preparation and packaging process is completed, providing high-quality dilute sulfuric acid to the market.

[0037] In a specific embodiment, the three-stage filtration system comprises multiple precision filters with filter elements ranging in size from 0.1 μm to 0.01 μm. This deep filtration of dilute sulfuric acid effectively removes tiny particles and impurities from the solution, significantly improving the particle size and quality of the sulfuric acid, ensuring it meets the high-standard semiconductor application requirements.

[0038] The working principle of the present invention is as follows: the amount of ultrapure water and concentrated sulfuric acid is calculated based on the concentration of the dilute sulfuric acid solution to be prepared. A first diaphragm pump 15 is used to transport the ultrapure water from the ultrapure water storage tank 1 to the dilution tank 6, and a diaphragm pump 16 is used to transport the concentrated sulfuric acid from the concentrated sulfuric acid storage tank 2 to the dilution tank 6. The ultrapure water spray device 5 and the concentrated sulfuric acid spray device 7 are used to evenly mix the solutions. An external heat exchanger 8 is used to reduce the heat during the dilution process to prevent thermal corrosion. The diluted dilute sulfuric acid is collected under real-time monitoring by a second concentration meter 9 after reaching the set concentration. After cooling in the second heat exchanger 11 via a circulation pump 17, it is transported to the dilute sulfuric acid storage tank 12 via a third diaphragm pump 18. In the dilute sulfuric acid storage tank 12, the dilute sulfuric acid undergoes deep filtration through a three-stage filtration system 13 to improve the particle size quality. After circulating filtration until the dilute sulfuric acid reaches the specified purity, it is finally transported to the packaging line via a fourth diaphragm pump 19 and filled into professional packaging products 14, completing the preparation and packaging process.

[0039] The utility model is a device for preparing electronic-grade dilute sulfuric acid, which has the characteristics of high-precision control, safety and stability, and convenient sampling and detection, and provides an efficient, accurate and safe solution for preparing dilute sulfuric acid for the electronics industry.

[0040] The above embodiments are merely preferred technical solutions of the present invention and should not be construed as limiting the present invention. The scope of protection of the present invention shall be the technical solutions set forth in the claims, including equivalent alternatives to the technical features of the technical solutions set forth in the claims. Equivalent alternatives and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. An electronic grade dilute sulfuric acid preparation device, characterized in that: It includes an ultrapure water storage tank (1), a concentrated sulfuric acid storage tank (2), a dilution tank (6), a heat exchanger and a dilute sulfuric acid storage tank (12), The ultrapure water storage tank (1) is connected to the dilution tank (6) via a first pipe, one end of the first pipe connected to the dilution tank is located in the middle of the dilution tank, and an ultrapure water spraying device (5) is provided at the other end of the first pipe connected to the dilution tank; The concentrated sulfuric acid storage tank (2) is connected to the dilution tank via a second pipe, one end of the second pipe connected to the dilution tank is located at the top of the dilution tank, and the other end of the second pipe connected to the dilution tank is provided with a concentrated sulfuric acid spraying device (7); The heat exchanger comprises a first heat exchanger (8) and a second heat exchanger (11), wherein the first heat exchanger (8) is wrapped around the outside of the dilution tank to reduce the heat generated during the dilution process and prevent thermal corrosion; The second heat exchanger (11) is arranged outside the dilution tank and connected to the dilution tank (6) through a third pipe, and is used to cool the dilute sulfuric acid; The dilute sulfuric acid storage tank (12) is connected to the heat exchanger (11) via a fourth pipeline and is used to store cooled dilute sulfuric acid.

2. A device for preparing electronic-grade dilute sulfuric acid according to claim 1, characterized in that: The electronic-grade dilute sulfuric acid preparation equipment further includes a filtering system (13) disposed outside the dilute sulfuric acid storage tank (12).

3. The electronic grade dilute sulfuric acid preparation equipment according to claim 1, wherein: The dilution tank (6) is provided with a temperature control system.

4. The electronic grade dilute sulfuric acid preparation equipment according to claim 1, wherein: The ultrapure water spraying device (5) is symmetrically distributed in the middle and upper part of the side wall of the dilution tank (6).

5. The electronic grade dilute sulfuric acid preparation equipment according to claim 1, wherein: The concentrated sulfuric acid spraying device (7) is arranged at the top middle position of the dilution tank (6).

6. The electronic grade dilute sulfuric acid preparation equipment according to claim 1, characterized in that: A first concentration meter (4) is provided in the concentrated sulfuric acid storage tank (2), and a flow meter and a control valve (3) are provided on the second pipeline.

7. The electronic grade dilute sulfuric acid preparation equipment according to claim 1, characterized in that: A second concentration meter (9) is provided at the bottom of the dilution tank (6), and a circulating dilute sulfuric acid outlet (10) is provided at the lower middle portion of the side wall of the dilution tank.

8. The electronic grade dilute sulfuric acid preparation equipment according to claim 1, characterized in that: A circulation pump (17) is provided on the third pipeline, and the circulation pump (17) is connected to the bottom of the dilution tank (6) through a pipeline.

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