CN212050528U

CN212050528U - High-efficient purification system of hydrogen fluoride

Info

Publication number: CN212050528U
Application number: CN202020321996.7U
Authority: CN
Inventors: 卫文碧; 向飞虎; 范如意; 张超
Original assignee: Hubei Wengfu Lantian Chemical Co ltd
Current assignee: Hubei Wengfu Lantian Chemical Co ltd
Priority date: 2020-03-16
Filing date: 2020-03-16
Publication date: 2020-12-01
Anticipated expiration: 2030-03-16

Abstract

The utility model relates to a high-efficient purification system of hydrogen fluoride, the system includes first heat exchanger, and first heat exchanger, first condenser and reation kettle pass through the pipeline and UNICOM in proper order, reation kettle top exhaust duct passes through pipeline and first purifying column UNICOM, the reation kettle bottom is through pipeline and second purifying column, second condenser, second heat exchanger, distilling column UNICOM in proper order, the distilling column passes through the pipeline and communicates with third condenser, milipore filter system in proper order. The utility model discloses a carry out the preliminary treatment at the raw materials to avoid the raw materials quality to cause the influence to hydrogen fluoride purity, in concentrated sulfuric acid decomposition produces hydrogen fluoride reaction, carry out the separation of thick step to the hydrogen fluoride in gas and the solution respectively, obtain hydrogen fluoride gas and get into rectifying column rectification, isolate high, low boiling impurity, obtain hydrogen fluoride condensate and pass through ultrafiltration treatment again, through raw materials preliminary treatment, the purifying column purifies, the rectification, physical membrane separation combines the processing to obtain electronic level hydrogen fluoride product.

Description

High-efficient purification system of hydrogen fluoride

Technical Field

The utility model relates to a belong to chemical industry technical field, concretely relates to high-efficient purification system of hydrogen fluoride.

Background

Hydrogen fluoride is the basis of modern fluorine chemical industry and is the most basic raw material for preparing elemental fluorine, various fluorine refrigerants, novel fluorine-containing materials, inorganic fluoride salts, various organic fluorides and the like. The natural fluorite resource relying on the existence of fluorine chemical industry is exhausted, people look to phosphorite associated fluorine, and hope to recover the associated fluorine resource from the production process of the phosphorus chemical industry. Mixing fluosilicic acid from a phosphate fertilizer plant with concentrated sulfuric acid to generate mixed gas of silicon tetrafluoride, hydrogen fluoride and the like, and absorbing the mixed gas by the concentrated sulfuric acid, wherein the silicon tetrafluoride enters a concentration system to be absorbed; the sulfuric acid after the reaction contains a large amount of hydrogen fluoride, and the hydrogen fluoride and the sulfuric acid are separated by distillation to obtain an anhydrous hydrogen fluoride product. The process does not remove impurities from the raw material fluosilicic acid, and chloride in the fluosilicic acid can interfere with the production of anhydrous hydrogen fluoride and influence the purity. In the cn201911048712.x document, in order to reduce the participation of water vapor in the hydrogen fluoride preparation process, the raw materials are dried, the energy consumption is high, and in the purification process, only the temperature reduction treatment is adopted, so that the high-boiling-point impurities are converted from a gas phase to a liquid phase or a solid phase through a temperature reduction mode, and the high-boiling-point impurities are removed, and the method only removes some high-boiling-point substances and does not completely remove clean impurities.

Disclosure of Invention

The utility model aims to solve the technical problem that a high-efficient purification system of hydrogen fluoride is provided, guarantee to obtain high-purity hydrogen fluoride product through combining the processing at raw materials preliminary treatment stage, production technology stage, purification stage.

In order to solve the technical problem, the utility model discloses the technical scheme who adopts is:

the utility model provides a high-efficient purification system of hydrogen fluoride, the system includes first heat exchanger, and first heat exchanger, first condenser and reation kettle pass through the pipeline UNICOM in proper order, reation kettle top exhaust duct passes through pipeline and first purifying column UNICOM, the reation kettle bottom passes through pipeline and second purifying column, second condenser, second heat exchanger, distillation column UNICOM in proper order, the distillation column passes through the pipeline and communicates in proper order with third condenser, milipore filter system.

Preferably, the exhaust pipe at the top of the first purification tower is communicated with the fourth condenser and the second heat exchanger in sequence.

Preferably, the reaction kettle is communicated with a sulfuric acid storage tank through a pipeline.

Preferably, a reboiler is arranged outside the bottom of the distillation tower.

Preferably, the distillation column comprises a lower column and an upper column, and the diameter of the lower column is larger than that of the upper column.

The utility model discloses beneficial effect:

1. the utility model discloses an carry out the preliminary treatment at the raw materials, fluosilicic acid is concentrated in with the raw materials, take off arsenic, iodine, compositions such as chloride ion, can avoid the raw materials quality to cause the influence to hydrogen fluoride purity, the use amount of raw materials hydrofluoric acid solution has also been reduced, in concentrated sulfuric acid decomposition produces hydrogen fluoride reaction, carry out the separation of thick step to the hydrogen fluoride in gas and the solution respectively, obtain hydrogen fluoride gas and get into the rectifying column rectification, isolate out high, low boiling impurity, it is handled again to obtain hydrogen fluoride condensate, through the raw materials preliminary treatment, the purifying column purifies, the rectification, physical membrane separation combines the processing to obtain electron level hydrogen fluoride product.

2. And the exhaust pipe at the top of the first purification tower is communicated with the fourth condenser and the second heat exchanger in sequence. By separating and purifying the gas in the product and the hydrogen fluoride in the liquid in the reaction, a small amount of hydrogen fluoride dissolved in the solution is separated and recovered, the product yield is improved, and the dilute sulfuric acid solution separated by the second purification tower can be further recycled.

3. The distillation column comprises a lower column and an upper column, the diameter of the lower column is larger than that of the upper column, the staying time of hydrogen fluoride gas in the upper column can be prolonged, and high-boiling-point impurities directly fall into the bottom of the lower column to be separated out, so that the separation effect is improved.

Drawings

FIG. 1: the utility model has a schematic structure;

wherein: the system comprises a first heat exchanger 1, a first condenser 2, a reaction kettle 3, a first purification tower 4, a second purification tower 5, a second condenser 6, a second heat exchanger 7, a distillation tower 8, a lower tower 801, an upper tower 802, a third condenser 9, an ultrafiltration membrane system 10, a fourth condenser 11, a sulfuric acid storage tank 12 and a reboiler 13.

Detailed Description

Example 1

As shown in fig. 1, a high-efficiency purification system for hydrogen fluoride, which comprises a first heat exchanger 1, is characterized in that: first heat exchanger 1, first condenser 2 and reation kettle 3 pass through the pipeline UNICOM in proper order, 3 top exhaust duct of reation kettle pass through pipeline and first purifying column 4 UNICOM, 3 bottoms of reation kettle pass through pipeline and second purifying column 5, second condenser 6, second heat exchanger 7, distillation column 8 UNICOM in proper order, distillation column 8 communicates in proper order through pipeline and third condenser 9, milipore filter system 10.

Preferably, the exhaust pipe at the top of the first purification tower 4 is communicated with the fourth condenser 11 and the second heat exchanger 7 in sequence.

Preferably, the reaction kettle 3 is communicated with a sulfuric acid storage tank 12 through a pipeline.

Preferably, a reboiler 13 is provided outside the bottom of the distillation column 8.

Preferably, the distillation column 8 comprises a lower column 801 and an upper column 802, and the diameter of the lower column 801 is larger than that of the upper column 802.

The working principle of the embodiment is as follows:

raw material fluosilicic acid (17.5-18 wt% of fluosilicic acid, 1.4-1.6wt% of chloride ions, 18-22mg/L of iodine, 8-19mg/L of arsenic, 0.04-0.25% of phosphorus pentoxide and the balance of water) is subjected to superheated steam heat exchange (the temperature of the superheated steam is 210 ℃ and 250 ℃ and the pressure is 0.7-0.85 MPa) through a first heat exchanger 1, vaporized gas enters a first condenser 2 for cooling, the fluosilicic acid is cooled into liquid as a raw material and enters a reaction kettle 3, the concentration of the condensed fluosilicic acid is 18.5-18.9wt%, the concentration of the chloride ions is 0.25-0.35wt%, the concentration of the iodine is 5-8mg/L, the concentration of the arsenic is 3-4mg/L, the concentration of the phosphorus pentoxide is 0.03-0.05%, and the balance of the water. And the rest gas in the later period of the first condenser 2 enters into a post-washing chamber and is discharged.

Concentrated acid fluorosilicic acid solution pretreated by reaction kettle 3Adding concentrated sulfuric acid into the solution to react to produce SiF₄HF, sulfuric acid and silicon dioxide, wherein the gas discharged from the top of the reaction kettle 3 comprises HF, water vapor and silicon dioxide, and the liquid discharged from the bottom of the reaction kettle 3 is a small amount of hydrogen fluoride solution contained in dilute sulfuric acid. Gas discharged from the top of the reaction kettle 3 enters the first purification tower 4 and is washed by purified water, water vapor and silicon dioxide are dissolved in water and are discharged from the bottom, and hydrogen fluoride gas is discharged from the top of the first purification tower 4 and then enters the fourth condenser 11 for condensation and discharge. The mixed solution of dilute sulfuric acid and hydrogen fluoride discharged from the bottom of the reaction kettle 3 enters a second purification tower 5, hydrogen fluoride gas is separated through the boiling point difference between sulfuric acid and hydrogen fluoride, and the hydrogen fluoride gas enters a second condenser 6 to be condensed into hydrogen fluoride liquid.

The hydrogen fluoride liquid discharged by the fourth condenser 11 and the second condenser 6 is crude HF, enters the second heat exchanger 7 for advanced preheating treatment, enters the distillation tower 8 for distillation separation, is rectified to remove high and low point impurities to obtain an anhydrous hydrogen chloride product, is condensed into hydrogen fluoride liquid by the third condenser 9, and then enters the ultrafiltration membrane system 10 (below 0.2 mu m) to obtain an electronic grade hydrogen fluoride product.

Claims

1. A high-efficiency purification system of hydrogen fluoride, which comprises a first heat exchanger (1), and is characterized in that: first heat exchanger (1), first condenser (2) and reation kettle (3) are through pipeline UNICOM in proper order, reation kettle (3) top exhaust duct passes through pipeline and first purifying column (4) UNICOM, pipeline and second purifying column (5), second condenser (6), second heat exchanger (7), distillation column (8) UNICOM in proper order are passed through to reation kettle (3) bottom, distillation column (8) communicate in proper order with third condenser (9), milipore filter system (10) through the pipeline.

2. The system for purifying hydrogen fluoride with high efficiency according to claim 1, wherein: and the exhaust pipe at the top of the first purification tower (4) is communicated with the fourth condenser (11) and the second heat exchanger (7) in sequence.

3. The system for purifying hydrogen fluoride with high efficiency according to claim 1, wherein: the reaction kettle (3) is communicated with a sulfuric acid storage tank (12) through a pipeline.

4. The system for purifying hydrogen fluoride with high efficiency according to claim 1, wherein: a reboiler (13) is arranged on the outer side of the bottom of the distillation tower (8).

5. The system for purifying hydrogen fluoride with high efficiency according to claim 1, wherein: the distillation tower (8) comprises a lower tower (801) and an upper tower (802), wherein the diameter of the lower tower (801) is larger than that of the upper tower (802).

6. The system for purifying hydrogen fluoride with high efficiency according to claim 1, wherein: the feed inlet of the spraying pipeline of the first purifying tower (4) is communicated with the purified water pipeline, and the feed inlet of the spraying pipeline of the second purifying tower (5) is communicated with the sulfuric acid storage tank (12).