Acid waste heat recovery device of anhydrous hydrogen fluoride

Abstract

The utility model discloses an acid waste heat recovery device of anhydrous hydrogen fluoride, which is characterized in that a first acid storage tank and a second acid storage tank are respectively connected with a first preheater, the first preheater is sequentially connected with a first mixed reaction tank and a second mixed reaction tank through pipelines, and the second mixed reaction tank is connected with a second preheater through an acid circulating pump; the second preheater is sequentially connected with a first silicon generator and a second silicon generator, the second silicon generator is connected with the first preheater through a second acid circulating pump, and the first preheater is sequentially connected with a steam heater, a hydrogen fluoride reboiler storage tank and a hydrogen fluoride stripping tower. According to the utility model, heat in high-temperature dilute sulphuric acid generated in the production process of anhydrous hydrogen fluoride is recycled through the plurality of preheaters, so that the steam consumption is reduced, energy conservation and consumption reduction are realized, and the environment-friendly concept is met.

Description

Technical Field

[0001] The utility model belongs to the technical field of heat recovery and utilization, and particularly relates to an acid waste heat recovery device for anhydrous hydrogen fluoride without water. Background Technique

[0002] Hydrogen fluoride is the basis of modern fluorochemical industry and has been widely used in industries such as chemical industry, petroleum, medicine, agriculture, electronics, atomic energy, etc. It is a strong oxidant and also the most basic raw material for preparing elemental fluorine, fluorine-containing new materials, inorganic fluorides, various organic fluorides such as fluorine refrigerants, etc. It can be formulated into hydrofluoric acid for various uses, used in graphite manufacturing and as a catalyst for manufacturing organic compounds, etc., and occupies a very important position in the national economy. At present, the production technology of anhydrous hydrogen fluoride mainly uses the fluorite-sulfuric acid method. In this method, fluorite powder, fuming sulfuric acid, and 98% sulfuric acid need to be mixed in a certain proportion and then reacted in a rotary reaction furnace. The generated crude hydrogen fluoride gas is subjected to procedures such as washing, crystallization, drying, cooling, and purification to obtain anhydrous hydrogen fluoride products. During the production process of anhydrous hydrogen fluoride, a large amount of heat is generated, such as a large amount of flue gas waste heat in the rotary reaction furnace, high-temperature sulfuric acid, etc.

[0003] Chinese Patent CN220205797U discloses a flue gas waste heat recovery and utilization system for the rotary reaction furnace of anhydrous hydrogen fluoride, including a rotary reaction furnace, a gas-fired hot blast stove, first, second, and third heat exchangers, an integrated DCS control system, a hot water circulation tank. The gas-fired hot blast stove is connected to the rotary reaction furnace, the first heat exchanger, the second heat exchanger, and the third heat exchanger; the rotary reaction furnace is connected to the gas-fired hot blast stove. The third heat exchanger is connected to a blower, and the third heat exchanger is connected to the first heat exchanger, a low-nitrogen burner, and the gas-fired hot blast stove. The low-nitrogen burner is connected to a natural gas pipeline. The second heat exchanger is connected to the hot water circulation tank through a heater, and the hot water circulation tank is connected to the second heat exchanger through a hot water circulation pump. It achieves the purpose of energy conservation and environmental protection.

[0004] Chinese Patent CN215026119U discloses an exhaust gas heat recovery and utilization device for the production of anhydrous hydrogen fluoride, including a heating box, a heating furnace, an exhaust gas treatment box, and a rectification reboiler. An air vent plate is installed inside the heating box through a connecting piece. The top of the air vent plate is communicated with the heating furnace through an inlet pipe, and the bottom of the air vent plate is communicated with the exhaust gas treatment box through an outlet pipe. One side of the heating box is communicated with a water inlet pipe, and the other side of the heating box is communicated with the rectification reboiler through a water outlet pipe. Through the cooperation between devices, it realizes using the generated exhaust gas to heat the condensed water inside the heating box and introducing the heated water into the rectification reboiler for recycling, and well recovers the heat of the exhaust gas.

[0005] However, the heat recovery devices currently applied in the production field of anhydrous hydrogen fluoride only focus on the heat recovery of the rotary kiln. In the production process of anhydrous hydrogen fluoride, sulfuric acid needs to be heated, so a large amount of high-temperature sulfuric acid will be generated. If the heat in the high-temperature sulfuric acid is not recovered, a large amount of heat will be wasted. Therefore, it is necessary to design a device that can recover and utilize the heat energy in high-temperature sulfuric acid, so as to achieve energy conservation and consumption reduction. Summary of the Invention

[0006] In view of the above technical problems, the utility model provides an acid waste heat recovery device for anhydrous hydrogen fluoride, which recovers and utilizes the heat in the high-temperature dilute sulfuric acid generated in the production process of anhydrous hydrogen fluoride through multiple preheaters, reduces the steam consumption, realizes energy conservation and consumption reduction, and conforms to the environmental protection concept.

[0007] To achieve the above object, the utility model provides an acid waste heat recovery device for anhydrous hydrogen fluoride. The first acid storage tank and the second acid storage tank are respectively connected to the first preheater. The first preheater is sequentially connected to the first mixing reaction tank and the second mixing reaction tank through pipelines. The second mixing reaction tank is connected to the second preheater through an acid circulation pump. The second preheater is sequentially connected to the first silicon generator and the second silicon generator. The second silicon generator is connected to the first preheater through a second acid circulation pump. The first preheater is sequentially connected to a steam heater, a hydrogen fluoride reboiler storage tank, and a hydrogen fluoride stripping tower.

[0008] Preferably, the first mixing reaction tank is connected to the second mixing reaction tank through an overflow pipeline.

[0009] Further preferably, the first mixing reaction tank is connected to a fluorosilicic acid storage tank.

[0010] Preferably, the first silicon generator is connected to the second silicon generator through an overflow pipeline.

[0011] Preferably, the second preheater is connected to a third acid storage tank through an acid pump.

[0012] Preferably, the second preheater is sequentially connected to a heat exchanger and a dilute sulfuric acid storage tank.

[0013] Further preferably, the heat exchanger is connected to a circulating water storage tank in a circulating manner.

[0014] The beneficial effects of the utility model are as follows: The heat in the high-temperature dilute sulfuric acid with different temperatures generated in the production process of anhydrous hydrogen fluoride is recovered through two preheaters, and is used to heat the mixed solution and the silicon tetrafluoride solution generated after the reaction with fluorosilicic acid, reducing the energy consumption for heating the relevant solutions subsequently, reducing the steam consumption, improving the utilization efficiency of heat energy, and reducing the production energy consumption. Brief Description of the Drawings

[0015] Figure 1This is the overall structural schematic diagram of the present utility model. In the figure, 1 is the first acid storage tank, 2 is the second acid storage tank, 3 is the first preheater, 4 is the first mixing reaction tank, 5 is the second mixing reaction tank, 6 is the first acid circulation pump, 7 is the second acid circulation pump, 8 is the acid pump, 9 is the steam heater, 10 is the first silicon generator, 11 is the second silicon generator, 12 is the hydrogen fluoride reboiler storage tank, 13 is the hydrogen fluoride stripping tower, 14 is the third acid storage tank, 15 is the second preheater, 16 is the circulating water storage tank, 17 is the fluorosilicic acid storage tank, 18 is the heat exchanger, and 19 is the dilute sulfuric acid storage tank. Detailed implementation manners

[0016] The technical solution of the present utility model will be further explained below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the following embodiments are only the preferred embodiments of the present utility model and should not be construed as a limitation of the present utility model. The protection scope of the present utility model shall be subject to the content recorded in the claims. Any modification or replacement made by those skilled in the art to the technical solution of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0017] Embodiment 1

[0018] As Figure 1 shown, an acid waste heat recovery device for anhydrous hydrogen fluoride, the first acid storage tank 1 and the second acid storage tank 2 are respectively connected to the tube layer of the first preheater 3, and the high-temperature acid in the two acid storage tanks is used for heating; the first preheater 3 is successively connected to the first mixing reaction tank 4 and the second mixing reaction tank 5 through pipelines, and the second mixing reaction tank 5 is connected to the shell layer of the second preheater 15 through the acid circulation pump 6 for heat exchange; the shell layer of the second preheater 15 is successively connected to the first silicon generator 10 and the second silicon generator 11, and the second silicon generator 11 is connected to the shell layer of the first preheater 3 through the second acid circulation pump 7 to realize heat exchange with the high-temperature acid in the first acid storage tank 1 and the second acid storage tank 2, thereby heating the fluorine-containing material; the first preheater 3 is successively connected to the steam heater 9, the hydrogen fluoride reboiler storage tank 12 and the hydrogen fluoride stripping tower 13, and the fluorine-containing material is further heated and then the fluorine-containing material escapes from the hydrogen fluoride reboiler storage tank 12.

[0019] Preferably, the first mixing reaction tank 4 is connected to the second mixing reaction tank 5 through an overflow pipeline.

[0020] More preferably, the first mixing reaction tank 4 is connected to the fluorosilicic acid storage tank 17, and fluorosilicic acid is added to the first mixing reaction tank 4 to react with the dilute sulfuric acid after heat exchange, thereby generating a fluorine-containing material.

[0021] Preferably, the first silicon generator 10 is connected to the second silicon generator 11 through an overflow pipeline.

[0022] Preferably, the tube layer of the second preheater 15 is connected to the third acid storage tank 14 via an acid pump 8, and the high-temperature acid in the third acid storage tank 14 is transported to the second preheater 15 to exchange heat with the solution in the second mixing reaction tank 5.

[0023] Preferably, the second preheater 15 is sequentially connected to a heat exchanger 18 and a dilute sulfuric acid storage tank 19. The acid after heat exchange is further cooled by circulating water in the heat exchanger 18 and then stored in the dilute sulfuric acid storage tank 19.

[0024] More preferably, the heat exchanger 18 is connected in a cycle with a circulating water storage tank 16 to continuously supply low-temperature water to the heat exchanger 18 to reduce the temperature of the acid.

[0025] Example 2

[0026] The high-temperature dilute sulfuric acid (about 220 °C) generated during the production of anhydrous hydrogen fluoride is respectively stored in a first acid storage tank 1 and a second acid storage tank 2. The high-temperature dilute sulfuric acid is transported to the tube layer of a first preheater 3 through a pipeline to exchange heat with the solution in the shell layer. The temperature of the dilute sulfuric acid output from the first preheater 3 is about 177 °C, and then it is transported to a first mixing reaction tank 4. Fluorosilicic acid is added to the first mixing reaction tank 4 from a fluorosilicic acid storage tank 17, and silicon tetrafluoride and hydrogen fluoride are generated by reaction and then overflow to the second mixing reaction tank. At this time, the temperature of the solution becomes about 95 °C;

[0027] The solution is transported to the shell layer of the second preheater 15 through a first acid circulation pump 6 for heat exchange and temperature rise, and then after rising to about 115 °C, it is transported to a first silicon generator 10 to generate silicon tetrafluoride by reaction and then overflows to a second silicon generator 11;

[0028] The solution in the second silicon generator 11 is transported to the shell layer of the first preheater 3 through a second acid circulation pump 7, and after heat exchange with the high-temperature dilute sulfuric acid, the temperature rises to about 140 °C, and then it is transported to a steam heater 9 for further heating, and finally, it is stored in a hydrogen fluoride stripping tower 13 after being processed by a hydrogen fluoride reboiler storage tank 12.

[0029] The third acid storage tank 14 stores high-temperature dilute sulfuric acid with a temperature of about 150 °C, which is transported to the tube layer of the second preheater 15 through an acid pump 8 to exchange heat with the solution output from the second mixing reaction tank 5, and after heat exchange, it enters the heat exchanger 18 to exchange heat with circulating water for cooling and then is stored in the dilute sulfuric acid storage tank 19.

Claims

1. An acid waste heat recovery device for anhydrous hydrogen fluoride, characterized in that: The first acid storage tank (1) and the second acid storage tank (2) are respectively connected to the first preheater (3). The first preheater (3) is connected to the first mixing reaction tank (4) and the second mixing reaction tank (5) in sequence through pipelines. The second mixing reaction tank (5) is connected to the second preheater (15) through an acid circulation pump (6). The second preheater (15) is connected to the first silicon generator (10) and the second silicon generator (11) in sequence. The second silicon generator (11) is connected to the first preheater (3) through a second acid circulation pump (7). The first preheater (3) is connected to a steam heater (9), a hydrogen fluoride reboiler storage tank (12), and a hydrogen fluoride stripping tower (13) in sequence.

2. The acid waste heat recovery device for anhydrous hydrogen fluoride according to claim 1, wherein: The first mixing reaction tank (4) is connected to the second mixing reaction tank (5) through an overflow pipeline.

3. The acid waste heat recovery device for anhydrous hydrogen fluoride according to claim 1 or 2, characterized in that: The first mixing reaction tank (4) is connected to a fluosilicic acid storage tank (17).

4. An acid waste heat recovery device for anhydrous hydrogen fluoride according to claim 1, characterized in that: The first silicon generator (10) is connected to the second silicon generator (11) through an overflow pipeline.

5. An acid waste heat recovery device for anhydrous hydrogen fluoride according to claim 1, characterized in that: The second preheater (15) is connected to a third acid storage tank (14) through an acid pump (8).

6. The acid waste heat recovery device for anhydrous hydrogen fluoride according to claim 1, characterized in that: The second preheater (15) is connected to a heat exchanger (18) and a dilute sulfuric acid storage tank (19) in sequence.

7. An acid waste heat recovery device for anhydrous hydrogen fluoride according to claim 6, characterized in that: The heat exchanger (18) is connected to a circulating water storage tank (16) in a circulating manner.

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