System for preparing electronic-grade hydrochloric acid by using Mannheim device

Abstract

The utility model relates to a system for preparing electronic-grade hydrochloric acid by using a Mannheim device. Comprising a potassium chloride storage tank, a desalted water pipeline and a concentrated sulfuric acid storage tank, the potassium chloride storage tank and the concentrated sulfuric acid storage tank are respectively connected with a Mannheim furnace, a byproduct hydrogen chloride gas pipeline of the Mannheim furnace is connected with a B acid washing tower, a gas pipeline in the B acid washing tower is connected with an A acid washing tower, and a gas pipeline in the A acid washing tower is connected with an inlet of a drying tower; a spraying pipeline at the upper part in the drying tower is connected with a concentrated sulfuric acid storage tank; a gas phase outlet of the drying tower is connected with an electronic-grade hydrochloric acid storage tank through a gas purifying and absorbing unit and a filtering unit in sequence; a bottom liquid phase outlet of the drying tower is connected with a concentrated sulfuric acid inlet of the Mannheim furnace; the method has the advantages of improving the added value of products and reducing the production cost.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic-grade hydrochloric acid production, in particular to a system for preparing electronic-grade hydrochloric acid by utilizing a Mannheim device. Background Art

[0002] The principle of the Mannheim potassium sulfate process is to evenly add sulfuric acid and potassium chloride into the reaction chamber of the "Mannheim furnace" through a feeder for reaction. At the same time, under the continuous stirring of the stirrer, the reactants, sulfuric acid and potassium chloride absorb a large amount of heat to produce potassium sulfate and HCl gas, and finally the potassium sulfate will be pushed out by the stirrer. The HCl gas passes through the B acid washing tower to produce B acid, and then passes through the A acid washing tower to produce A acid after washing and absorption; the by-product hydrochloric acid of the device contains impurities such as free chlorine, organic matter, and metal ions, which are not easy to use, resulting in an increase in the storage of dilute hydrochloric acid, affecting the production capacity of sulfur-based fertilizers, and sometimes additional fees are required for the disposal of the by-product hydrochloric acid of compound fertilizers; the A acid refers to the acid containing very little SO4 2- hydrochloric acid; B acid refers to acid containing SO4 2- About 5% hydrochloric acid.

[0003] In addition, due to its high added value and broad market prospects, the current production of electronic-grade hydrochloric acid uses industrial-grade synthetic hydrochloric acid as raw material. For example: Chinese Patent Publication No. CN110436416A, the name of the invention patent is: A process for preparing electronic-grade hydrochloric acid by removing free chlorine; it discloses a method for preparing electronic-grade hydrochloric acid using industrial-grade hydrochloric acid. This production method has distance requirements for the manufacturer and the chlor-alkali plant. If the distance from the chlor-alkali plant is far, the freight will increase, resulting in a higher production cost. Utility Model Content

[0004] The utility model aims to provide a system for preparing electronic grade hydrochloric acid by using a Mannheim device, so as to overcome the defects in the prior art.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A system for preparing electronic-grade hydrochloric acid by using a Mannheim device comprises a potassium chloride storage tank, a desalted water pipeline and a concentrated sulfuric acid storage tank, wherein the potassium chloride storage tank and the concentrated sulfuric acid storage tank are respectively connected to a Mannheim furnace in the Mannheim device, a byproduct hydrogen chloride gas pipeline of the Mannheim furnace is connected to a B acid washing tower, a hydrogen chloride gas pipeline after washing in the B acid washing tower is connected to an A acid washing tower, a hydrogen chloride gas pipeline after absorption in the A acid washing tower is connected to a lower inlet of a drying tower, a spray pipeline in the upper part of the drying tower is connected to a concentrated sulfuric acid storage tank, a gas phase outlet at the top of the drying tower is connected to the electronic-grade hydrochloric acid storage tank through a gas purification absorption unit and a filtering unit in sequence; a liquid phase outlet at the bottom of the drying tower is connected to a concentrated sulfuric acid inlet of the Mannheim furnace; a first tee is arranged between the liquid phase outlet at the bottom of the drying tower and the concentrated sulfuric acid inlet of the Mannheim furnace, a second tee is arranged between the concentrated sulfuric acid storage tank and the spray pipeline, and a first circulation pump and a first heat exchanger are arranged between the first tee and the second tee.

[0007] The beneficial effects of the utility model are as follows: through the above-mentioned setting of the utility model, the coupling of the Mannheim device and the electronic-grade hydrochloric acid preparation device can be realized. On the one hand, the hydrogen chloride gas used for absorbing A acid can be effectively recycled while preparing potassium sulfate, and on the other hand, the problem of the existing electronic-grade hydrochloric acid preparation process relying on chlorine and alkali can be overcome, thereby achieving the advantages of increasing product added value and reducing production costs; further, the utility model can use sulfuric acid used as a raw material in the Mannheim device as a desiccant in the preparation of electronic-grade hydrochloric acid, and the sulfuric acid used as a desiccant can be reused as a raw material, thereby eliminating the need to purchase additional desiccant and achieving the characteristic of full utilization of sulfuric acid.

[0008] Preferably, the gas purification absorption unit includes a scrubbing tower, the gas phase outlet at the top of the drying tower is connected to the inlet of the scrubbing tower, the gas phase outlet at the top of the scrubbing tower is connected to the inlet of the absorption tower, the liquid phase outlet at the bottom of the absorption tower is connected to the filtration unit through a third tee, and the third end of the third tee is connected to the circulating liquid inlet at the top of the absorption tower through a second circulation pump and a second heat exchanger; the scrubbing tower and the upper inner part of the absorption tower are respectively provided with demisters.

[0009] Preferably, the tail gas outlet of the Mannheim furnace, the tail gas outlet of the A acid washing tower, the tail gas outlet of the B acid washing tower and the tail gas outlet of the absorption tower are respectively connected to the tail gas absorption tower in the Mannheim device, and the gas phase outlet of the tail gas absorption tower is connected to the chimney.

[0010] Preferably, the liquid phase outlet of the A acid washing tower is connected to the A acid tank, and the liquid phase outlet of the B acid washing tower and the liquid phase outlet of the gas washing tower are respectively connected to the B acid tank.

[0011] Preferably, the ultrapure water inlets at the top of the scrubbing tower and the absorption tower are respectively connected to ultrapure water pipelines.

[0012] Preferably, a reagent adding pipeline connected to the scrubber is provided at the lower part of the scrubber, and a circulation pipeline at the lower part of the scrubber is connected to a circulation liquid inlet at the upper part of the scrubber through a third circulation pump and a third heat exchanger.

[0013] Preferably, a fourth heat exchanger and a circulation tank are sequentially arranged between the liquid phase outlet at the bottom of the absorption tower and the third tee.

[0014] Preferably, the filtration unit comprises three microporous filters connected in series.

[0015] According to the above scheme, a system for preparing electronic-grade hydrochloric acid using a Mannheim device is prepared. The utility model uses the hydrogen chloride used to absorb A acid in the existing Mannheim device as a raw material, which not only does not need to use industrial-grade hydrochloric acid as a raw material, but also can save the hydrochloric acid analysis device and the corresponding process. The essence of the utility model is that through the coupling of the Mannheim device and the electronic-grade hydrochloric acid preparation device, on the one hand, the byproduct gas phase can be effectively recycled while preparing potassium sulfate, and on the other hand, the problem of the existing electronic-grade hydrochloric acid preparation process relying on chlorine and alkali can be overcome, thereby achieving the advantages of increasing product added value and reducing production costs; further, the utility model can use sulfuric acid as a raw material in the Mannheim device as a desiccant in the preparation of electronic-grade hydrochloric acid, and the sulfuric acid used as a desiccant is reused as a raw material, so that there is no need to purchase additional desiccant, and the characteristics of sulfuric acid being fully utilized are achieved. In addition, the utility model uses the waste removal system in the Mannheim device to treat the waste in the electronic-grade hydrochloric acid preparation device, thereby achieving the characteristics of saving investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the utility model.

[0017] In the figure: 1. Potassium chloride storage tank; 2. Desalted water pipeline; 3. Concentrated sulfuric acid storage tank; 4. Mannheim furnace; 5. B acid washing tower; 6. A acid washing tower; 7. Drying tower; 8. Spray pipeline; 9. Electronic grade hydrochloric acid storage tank; 10. First tee; 11. Second tee; 12. First circulation pump; 13. First heat exchanger; 14. Scrubber; 15. Absorption tower; 16. Third tee; 17. Second circulation pump; 18. Second heat exchanger; 19. Tail gas absorption tower; 20. Chimney; 21. A acid tank; 22. Ultrapure water pipeline; 23. Drug addition pipeline; 24. Third heat exchanger; 25. Fourth heat exchanger; 26. Circulation tank; 27. Microporous filter; 28. B acid tank; 29. ​​Defogger; 30. Third circulation pump. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0019] Reference Figure 1 As shown, the utility model is a system for preparing electronic grade hydrochloric acid by using a Mannheim device, comprising a potassium chloride storage tank 1, a desalted water pipeline 2 and a concentrated sulfuric acid storage tank 3, the potassium chloride storage tank 1 and the concentrated sulfuric acid storage tank 3 are respectively connected to a Mannheim furnace 4 in the Mannheim device, a byproduct hydrogen chloride gas pipeline of the Mannheim furnace 4 is connected to a B acid washing tower 5, a hydrogen chloride gas pipeline after washing in the B acid washing tower 5 is connected to an A acid washing tower 6, a hydrogen chloride gas pipeline after absorption in the A acid washing tower 6 is connected to a lower inlet of a drying tower 7, and an upper inlet of the drying tower 7 is connected to a desalted water pipeline 2 and a concentrated sulfuric acid storage tank 3. The spray pipe 8 at the bottom is connected to the concentrated sulfuric acid storage tank 3, and the gas phase outlet at the top of the drying tower 7 is connected to the electronic grade hydrochloric acid storage tank 9 through the gas purification absorption unit and the filtration unit in turn; the liquid phase outlet at the bottom of the drying tower 7 is connected to the concentrated sulfuric acid inlet of the Mannheim furnace 4; a first tee 10 is arranged between the liquid phase outlet at the bottom of the drying tower 7 and the concentrated sulfuric acid inlet of the Mannheim furnace 4, a second tee 11 is arranged between the concentrated sulfuric acid storage tank 3 and the spray pipe 8, and a first circulation pump 12 and a first heat exchanger 13 are arranged between the first tee 10 and the second tee 11. The utility model is an improvement based on the existing Mannheim device, and utilizes the hydrogen chloride used for absorbing A acid in the Mannheim device as a raw material to couple with the electronic grade hydrochloric acid preparation device to achieve the characteristics of increasing product added value and reducing operating costs. In the utility model, the hydrogen chloride gas absorbed from the A acid washing tower 6 is a by-product of potassium sulfate production, and has the characteristics of high water content, many impurities and unstable hydrogen chloride gas content. Based on this, the utility model uses the raw concentrated sulfuric acid in the Mannheim device as a desiccant to dry the above tail gas, and further removes impurities through a gas purification absorption unit and a filtering unit on this basis to achieve the purpose of preparing electronic grade hydrochloric acid. At the same time, the sulfuric acid used as a desiccant is returned to the Mannheim furnace 4 as a raw material to achieve full utilization of sulfuric acid and reduce operating costs and waste acid treatment costs.

[0020] Furthermore, the gas purification absorption unit includes a scrubbing tower 14, the gas phase outlet at the top of the drying tower 7 is connected to the inlet of the scrubbing tower 14, the gas phase outlet at the top of the scrubbing tower 14 is connected to the inlet of the absorption tower 15, the liquid phase outlet at the bottom of the absorption tower 15 is connected to the filtration unit through the third tee 16, and the third end of the third tee 16 is connected to the circulating liquid inlet at the top of the absorption tower 15 through the second circulating pump 17 and the second heat exchanger 18; the upper inner parts of the scrubbing tower 14 and the absorption tower 15 are respectively provided with demisters 29. The gas purification absorption unit in the utility model comprises a scrubber 14 and an absorption tower 15. The dried hydrogen chloride gas enters from the bottom of the scrubber 14 and contacts with the leaching liquid entering the circulation from the top of the tower, and the dust, metal ions, organic matter, etc. therein are washed and absorbed and refluxed to the bottom of the tower kettle; a quantitative reducing agent is added to the tower kettle to remove free chlorine in the hydrogen chloride gas; after the circulating leaching liquid is cooled, it is pumped into the hydrogen chloride gas in the leaching tower at the top of the tower, and the washed hydrogen chloride gas passes through a demister 29 to remove acid mist and macromolecular impurities; after washing and impurity removal in the scrubber 14, clean HCl gas is obtained; dry Clean hydrogen chloride gas enters from the bottom of the absorption tower 15, and contacts with the HCl liquid sprayed from the top of the absorption tower 15 in reverse direction for absorption and concentration, so as to meet the requirements for preparing electronic grade hydrochloric acid; the reducing agent in the scrubber 14 includes stannous oxide, hydrazine hydrate and other agents for reducing Cl2; the circulating eluent is a saturated hydrochloric acid solution, and the cooling of the circulating eluent refers to the use of a 5-10°C freezing medium for cooling; the absorption liquid in the absorption tower 15 is ultrapure water, with a resistivity of ≥18.2MΩ*cm and metal ions ≤1ppt; the absorption liquid is cooled by a 5-10°C freezing medium.

[0021] Further, the tail gas outlet of the Mannheim furnace 4, the tail gas outlet of the A acid washing tower 6, the tail gas outlet of the B acid washing tower 5 and the tail gas outlet of the absorption tower 15 are respectively connected to the tail gas absorption tower 19 in the Mannheim device, and the gas phase outlet of the tail gas absorption tower 19 is connected to the chimney 20. The waste gas produced in the utility model can be uniformly treated by the tail gas absorption tower 19 in the Mannheim device and then discharged from the chimney 20. The waste gas produced in the utility model includes the tail gas from the Mannheim furnace 4 in the Mannheim device, the tail gas from the A acid washing tower 6, the tail gas from the B acid washing tower 5 and the tail gas from the absorption tower 15 in the electronic grade hydrochloric acid preparation device.

[0022] Furthermore, the liquid phase outlet of the A acid washing tower 6 is connected to the A acid tank 21, and the liquid phase outlet of the B acid washing tower 5 and the liquid phase outlet of the gas washing tower 14 are respectively connected to the B acid tank 28. The byproduct acid produced in the utility model is also treated by the device for treating waste acid in the Mannheim device; the treatment of the above-mentioned waste gas and waste acid can achieve the feature of avoiding the need to set up a waste treatment device in the electronic grade hydrochloric acid preparation device, so as to achieve the advantage of saving investment costs.

[0023] Furthermore, the ultrapure water inlets at the tops of the scrubbing tower 14 and the absorption tower 15 are respectively connected to the ultrapure water pipeline 22 .

[0024] Furthermore, a reagent adding pipeline 23 connected to the scrubber 14 is provided at the lower part of the scrubber 14 , and a circulation pipeline at the lower part of the scrubber 14 is connected to a circulation liquid inlet at the upper part of the scrubber 14 through a third circulation pump 30 and a third heat exchanger 24 .

[0025] Furthermore, a fourth heat exchanger 25 and a circulation tank 26 are sequentially arranged between the liquid phase outlet at the bottom of the absorption tower 15 and the third three-way connection 16 .

[0026] Furthermore, the filtering unit includes three microporous filters 27 connected in series.

[0027] The utility model also provides a method for preparing an electronic grade hydrochloric acid system using a Mannheim device, the method comprising the following steps:

[0028] Step 1: Potassium chloride in potassium chloride storage tank 1 and concentrated sulfuric acid in concentrated sulfuric acid storage tank 3 enter Mannheim furnace 4 for stirring reaction, hydrogen chloride gas produced as a byproduct of the reaction enters B acid washing tower 5, and the liquid phase after circulating washing enters B acid tank 28; the hydrogen chloride gas after circulating washing enters A acid washing tower 6 for circulating washing and absorption;

[0029] Step 2: The liquid phase after cyclic washing and absorption enters the A acid tank 21; the hydrogen chloride gas after cyclic washing enters the drying tower 7, and countercurrently contacts with the concentrated sulfuric acid from the concentrated sulfuric acid storage tank 3 to absorb moisture and remove potassium chloride and sulfate ion impurities dissolved in the water; the sulfuric acid after absorbing moisture and impurities in the drying tower 7 enters the Mannheim furnace 4 for repeated use; the dried hydrogen chloride gas enters the scrubbing tower 14;

[0030] Step 3: The dried hydrogen chloride gas enters the scrubber 14 and then moves upward to countercurrently contact with the circulating water to remove dust, metal ions, organic matter and free chlorine in the dried hydrogen chloride gas; the circulating water includes ultrapure water from the ultrapure water pipeline 22 and a reducing agent added from the agent adding pipeline 23, wherein the reducing agent is stannous oxide and hydrazine hydrate;

[0031] Step 4: The hydrogen chloride gas after impurities removal by the scrubber 14 enters the absorption tower 15, and is reversely contacted with the HCl solution circulating in the absorption tower 15 for absorption. When the concentration in the circulation tank 26 reaches 37±0.5%, it is filtered through the three-stage microporous filter 27 and then sent to the electronic grade hydrochloric acid storage tank 9;

[0032] Step 5: The tail gas in the Mannheim furnace 4, the tail gas in the A acid washing tower 6, the tail gas in the B acid washing tower 5 and the tail gas in the absorption tower 15 are respectively sent to the tail gas absorption tower 19 through the corresponding tail gas outlets for tail gas absorption, and the gas after tail gas absorption is discharged through the chimney 20;

[0033] Step 6: The inner tops of the scrubber tower 14 and the absorption tower 15 are both provided with demisters 29 for removing acid mist and macromolecular impurities.

[0034] In the utility model, the hydrogen chloride used for absorbing A acid in the Mannheim device is used as a raw material. The hydrogen chloride contains sulfuric acid, saturated water vapor, air, dust, metal ions and organic matter, etc. The content of hydrogen chloride is approximately how much, and it will fluctuate with the operation of the system; therefore, although the electronic-grade hydrochloric acid preparation device of the utility model eliminates the hydrochloric acid analysis device and the related analysis process, the hydrogen chloride gas in the utility model has more impurities and the content is unstable, which results in the poor quality of the raw material compared with the traditional production method, that is, the purification is difficult; part of the concentrated sulfuric acid described in the utility model is used as a raw material for producing potassium sulfate in the Mannheim furnace 4, and the other part is used as a desiccant in the drying tower 7. As a desiccant, it can remove moisture on the one hand, and dissolve hydrogen chloride on the other hand. Soluble impurities in the gas are removed to achieve the purpose of preliminary purification. The concentration of concentrated sulfuric acid is 98%. The concentration of concentrated sulfuric acid after drying by the drying tower 7 is preferably not less than 95%, so that it can be re-entered into the Mannheim furnace 4 for reuse; further, the utility model further removes impurities from the dried gas through the scrubbing tower 14. The impurity removal uses a saturated hydrochloric acid solution in combination with a reducing agent to remove dust, metal ions, organic matter and free chlorine in the gas, that is: ultrapure water absorbs hydrogen chloride gas in the scrubbing tower 14 to form a saturated hydrochloric acid solution, and the saturated hydrochloric acid solution is used to absorb the above impurities to achieve the characteristic of purifying hydrogen chloride gas; the saturated hydrochloric acid solution after absorbing impurities is recovered as waste acid into the B acid tank 28 of the Mannheim device.

[0035] Test example:

[0036] The dilute hydrochloric acid produced by potassium sulfate with the existing Mannheim device is generally sold at a price of less than 100 yuan / ton. According to the annual production of 200,000 tons of sulfur-based fertilizer production equipment, the by-product is about 70,000 tons of dilute hydrochloric acid, and the normal sales income is about 7 million yuan. The hydrochloric acid with a product purity reaching electronic grade (G3 grade or above) that can be produced by the utility model has a sales price of more than 2,200 yuan / t. Based on 10,000 tons of electronic grade products, the sales income can be increased by 21 million yuan.

[0037] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A system for preparing electronic grade hydrochloric acid using a Mannheim device, comprising a potassium chloride storage tank (1), a desalted water pipeline (2) and a concentrated sulfuric acid storage tank (3), wherein the potassium chloride storage tank (1) and the concentrated sulfuric acid storage tank (3) are respectively connected to a Mannheim furnace (4) in the Mannheim device, a byproduct hydrogen chloride gas pipeline of the Mannheim furnace (4) is connected to a B acid washing tower (5), and a hydrogen chloride gas pipeline after washing in the B acid washing tower (5) is connected to an A acid washing tower (6), characterized in that: The hydrogen chloride gas pipeline absorbed in the A acid washing tower (6) is connected to the lower inlet of the drying tower (7), the spray pipeline (8) in the upper part of the drying tower (7) is connected to the concentrated sulfuric acid storage tank (3), and the gas phase outlet at the top of the drying tower (7) is connected to the electronic grade hydrochloric acid storage tank (9) through the gas purification absorption unit and the filtering unit in sequence; The bottom liquid phase outlet of the drying tower (7) is connected to the concentrated sulfuric acid inlet of the Mannheim furnace (4); a first tee (10) is provided between the bottom liquid phase outlet of the drying tower (7) and the concentrated sulfuric acid inlet of the Mannheim furnace (4); a second tee (11) is provided between the concentrated sulfuric acid storage tank (3) and the spray pipe (8); and a first circulation pump (12) and a pipe path of a first heat exchanger (13) are provided between the first tee (10) and the second tee (11).

2. A system for preparing electronic grade hydrochloric acid using a Mannheim device according to claim 1, characterized in that: The gas purification absorption unit comprises a scrubbing tower (14), the gas phase outlet at the top of the drying tower (7) is connected to the inlet of the scrubbing tower (14), the gas phase outlet at the top of the scrubbing tower (14) is connected to the inlet of the absorption tower (15), the liquid phase outlet at the bottom of the absorption tower (15) is connected to the filtering unit through a third tee (16), and the third end of the third tee (16) is connected to the circulating liquid inlet at the top of the absorption tower (15) through a second circulating pump (17) and a second heat exchanger (18); The upper inner parts of the scrubbing tower (14) and the absorption tower (15) are respectively provided with demisters (29).

3. A system for preparing electronic grade hydrochloric acid using a Mannheim device according to claim 2, characterized in that: The tail gas outlet of the Mannheim furnace (4), the tail gas outlet of the A acid washing tower (6), the tail gas outlet of the B acid washing tower (5) and the tail gas outlet of the absorption tower (15) are respectively connected to the tail gas absorption tower (19) in the Mannheim device, and the gas phase outlet of the tail gas absorption tower (19) is connected to the chimney (20).

4. A system for preparing electronic grade hydrochloric acid using a Mannheim device according to claim 2, characterized in that: The liquid phase outlet of the A acid washing tower (6) is connected to the A acid tank (21), and the liquid phase outlet of the B acid washing tower (5) and the liquid phase outlet of the gas washing tower (14) are respectively connected to the B acid tank (28).

5. A system for preparing electronic grade hydrochloric acid using a Mannheim device according to claim 2, characterized in that: The ultrapure water inlets at the tops of the scrubbing tower (14) and the absorption tower (15) are respectively connected to the ultrapure water pipeline (22).

6. A system for preparing electronic grade hydrochloric acid using a Mannheim device according to claim 5, characterized in that: A reagent adding pipeline (23) connected to the scrubbing tower (14) is provided at the lower part of the scrubbing tower (14), and a circulation pipeline at the lower part of the scrubbing tower (14) is connected to a circulation liquid inlet at the upper part of the scrubbing tower (14) through a third circulation pump (30) and a third heat exchanger (24).

7. A system for preparing electronic grade hydrochloric acid using a Mannheim device according to claim 2, characterized in that: A fourth heat exchanger (25) and a circulation tank (26) are arranged in sequence between the liquid phase outlet at the bottom of the absorption tower (15) and the third tee (16).

8. A system for preparing electronic grade hydrochloric acid using a Mannheim device according to claim 1, characterized in that: The filtration unit comprises three microporous filters (27) connected in series.

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