Treatment device and method for reaction medium leakage around heating electrode of molten salt chlorination furnace

Abstract

The invention belongs to the technical field of titanium chemical industry, and relates to a treatment device and method for reaction medium leakage around a heating electrode of a molten salt chlorination furnace. The device comprises a gas washing unit which is filled with washing liquid for washing impurity gas; the pipeline unit comprises a gas inlet pipeline, a gas outlet pipeline and a gas extractor arranged on the gas inlet pipeline and / or the gas outlet pipeline, gas around the heating electrode is introduced into the gas washing unit through the gas inlet pipeline to be washed, and the washed gas is discharged to the periphery of the heating electrode through the gas outlet pipeline. The device can realize real-time purification around the heating electrode of the molten salt chlorination furnace, and effectively solves the problem of leakage of a reaction medium of the molten salt chlorination furnace.

Description

Technical Field

[0001] The invention belongs to the technical field of titanium chemical industry, and in particular relates to a device and method for processing leakage of reaction medium around heating electrodes of a molten salt chlorination furnace. Background Art

[0002] Before the production of the molten salt chlorination furnace, the molten salt must be heated and insulated by graphite electrode heating. Generally, the temperature is raised to about 750°C. The heat release of the chlorination reaction can be controlled by controlling the amount of coke, titanium slag and chlorine. At this time, the heating electrode can be turned off. The lining of the molten salt chlorination furnace is built with clay bricks. The clay castable produces a tiny gap around the graphite electrode during the drying and shrinking process. In the range of 20°C-1000°C, the thermal expansion coefficient of the clay castable is 4.5-6.0×10 -6 m / ℃, while the thermal expansion coefficient of graphite electrode is 1.5×10 -6 m / ℃, due to the large difference in thermal expansion coefficients, the gap between the graphite electrode and the refractory material increases, and at the operating temperature, the gas will leak out along the gap. Leakage of the reaction medium around the heating electrode of the molten salt chlorination furnace may cause chemical burns, poisoning hazards, fire and explosion, electrical failure and other safety accidents.

[0003] In the prior art, leakage of reaction medium around the heating electrode of the molten salt chlorination furnace is often prevented by selecting high-quality equipment, regularly checking seals to ensure seal maintenance, real-time pressure and temperature monitoring, and strict compliance with standard operations. Once a leak occurs, the common treatment method is to stop the operation of the molten salt chlorination furnace, effectively isolate the leak area, collect the leaked material and place it in a special container for subsequent treatment, check the leak point and repair the leak point. Among them, solid and liquid leaks such as reaction molten salt are relatively easy to collect, while gaseous leaks are prone to non-directional volatilization and are extremely difficult to collect.

[0004] Currently, there is no solution that can effectively solve the problem of reaction medium leakage in molten salt chlorination furnaces. Summary of the invention

[0005] In view of this, the present invention proposes a device and method for processing leakage of reaction medium around heating electrodes of a molten salt chlorination furnace.

[0006] In order to solve at least one of the above technical problems, the present invention adopts the following technical solution: According to the present invention, a device for processing leakage of reaction medium around the heating electrode of a molten salt chlorination furnace is provided, comprising: a gas washing unit, which contains a washing liquid for washing impurity gas; a pipeline unit, which includes an air inlet pipeline, an air outlet pipeline and an exhaust device arranged on the air inlet pipeline and / or the air outlet pipeline, wherein the gas around the heating electrode is introduced into the gas washing unit through the air inlet pipeline for washing, and the washed gas is discharged to the surrounding of the heating electrode through the air outlet pipeline.

[0007] According to one embodiment of the present invention, the gas washing unit is a water circulation washing unit, and the washing liquid is water.

[0008] According to one embodiment of the present invention, the gas washing unit is an alkaline solution circulation washing unit, and the washing liquid is alkaline solution.

[0009] According to one embodiment of the present invention, the gas washing unit comprises a water circulation washing unit and an alkali solution circulation washing unit connected in series.

[0010] According to one embodiment of the present invention, the gas washing unit is a dual-purpose washing unit, comprising a water circulation washing unit and an alkali liquid circulation washing unit in parallel, wherein the air inlet end of the water circulation washing unit and the alkali liquid circulation washing unit is provided with a first valve, and the air outlet end of the water circulation washing unit and the alkali liquid circulation washing unit is provided with a second valve.

[0011] According to one embodiment of the present invention, the processing device also includes: a detection unit, including a first detection component installed around the heating electrode, the first detection component is configured to detect the content of impurity gas around the heating electrode; wherein the first valve and the second valve are communicated with the first detection component, and are configured to connect to the pipeline where the water circulation washing unit is located in response to the content of the impurity gas meeting a preset condition, and to connect to the pipeline where the alkali liquid circulation washing unit is located in response to the content of the impurity gas not meeting the preset condition.

[0012] According to an embodiment of the present invention, the content of the impurity gas satisfies a preset condition, which includes: the mass percentage of chlorine in the gas around the heating electrode drops below 10 ppm.

[0013] According to one embodiment of the present invention, the processing device further comprises: a detection unit, comprising a second detection component disposed in the alkali solution circulating washing unit, wherein the second detection component is configured to detect the carbonate content in the alkali solution circulating washing unit.

[0014] According to an embodiment of the present invention, the processing device further comprises: a control unit, which is in communication with the second detection component and is configured to replace the alkaline solution in response to the carbonate content being higher than a set threshold.

[0015] According to the present invention, a method for treating leakage of reaction medium around a heating electrode of a molten salt chlorination furnace is provided, and a treatment device described in any of the above embodiments is arranged at the heating electrode.

[0016] By adopting the above technical solution, the present invention has at least one of the following advantages compared with the prior art: 1. The device for treating leakage of reaction medium around the heating electrode of the molten salt chlorination furnace according to the present invention has a simple structure, and does not need to change the original structure of the molten salt chlorination furnace. Only a slight modification is required to achieve effective purification around the heating electrode of the molten salt chlorination furnace; 2. The method for treating the leakage of the reaction medium around the heating electrode of the molten salt chlorination furnace according to the present invention can realize the real-time purification around the heating electrode of the molten salt chlorination furnace, and fundamentally avoid the adverse effects caused by the leakage of the reaction medium around the heating electrode; 3. The method for treating leakage of reaction medium around heating electrodes of molten salt chlorination furnace according to the present invention detects the impurity gas content around the hot electrode and the purification capacity of the treatment device by using a detection unit, so that the purification function is more perfect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of a device for processing leakage of reaction medium around a heating electrode of a molten salt chlorination furnace according to an embodiment of the present invention is shown; Figure 2 A schematic diagram showing a device for processing leakage of reaction medium around a heating electrode of a molten salt chlorination furnace according to another embodiment of the present invention is shown; Figure 3 A schematic diagram of a device for processing leakage of reaction medium around a heating electrode of a molten salt chlorination furnace according to yet another embodiment of the present invention is shown.

[0019] In the accompanying drawings, 100. Heating electrode; 200, gas washing unit, 210, water circulation washing unit, 220, alkali solution circulation washing unit; 300, pipeline unit, 310, air inlet pipeline, 320, air outlet pipeline, 330, air extraction device, 340, first valve, 350, second valve; 400, detection unit, 410, first detection component, 420, second detection component. DETAILED DESCRIPTION

[0020] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0021] It should be understood that the embodiments of the present invention shown in the exemplary embodiments are only illustrative. Although only a few embodiments are described in detail in the present invention, it is easy for those skilled in the art to appreciate that multiple modifications are feasible without actually departing from the teaching of the subject matter of the present invention. Accordingly, all such modifications should be included within the scope of the present invention. Without departing from the gist of the present invention, other replacements, modifications, changes and deletions may be made to the design, operating conditions and parameters of the following exemplary embodiments.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field of the present invention; the terms used in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. For example, the directions or positions indicated by the terms "length", "width", "up", "down", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the directions or positions shown in the drawings, which are only for the convenience of description and should not be understood as limitations on the present technical solution.

[0023] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

[0024] The gas produced by the molten salt chlorination furnace during normal production has a complex composition, which contains a certain amount of chlorine, hydrogen chloride, carbon dioxide, etc. When the reaction medium around the heating electrode of the molten salt chlorination furnace leaks into gas, the exhaust gas of the molten salt chlorination furnace needs to be treated in order to ensure that the gas can meet the emission standards.

[0025] According to one aspect of the present invention, a device for treating leakage of reaction medium around heating electrodes of a molten salt chlorination furnace is provided. Figure 1As shown, it generally includes: a gas washing unit 200 and a pipeline unit 300. Specifically, the gas washing unit 200 contains a washing liquid for washing impurity gas; the pipeline unit 300 may include an air inlet pipeline 310, an air outlet pipeline 320, and an exhaust device 330 arranged on the air inlet pipeline 310 and / or the air outlet pipeline 320. Among them, a sealed gas delivery pipeline is connected between the molten salt chlorination furnace and the gas washing unit 200, and the negative pressure generated by the exhaust device 330 such as a fan and a vacuum pump is used to suck the gas from around the heating electrode 100, and then transported to the gas washing unit 200 along the air inlet pipeline 310 for washing, and the washed gas is discharged to around the heating electrode 100 through the air outlet pipeline 320.

[0026] In one embodiment of the present invention, the gas washing unit 200 may be a water circulation washing unit 210 using water as a washing liquid, and water is used to circulate and wash the gas around the heating electrode of the molten salt chlorination furnace to absorb the impurity gas in the gas. Specifically, the impurity gas around the heating electrode 100 is introduced into the water circulation washing unit 210 and is fully contacted with water. The impurity gas will be transferred to the water by dissolving or chemical reaction, for example, hydrogen chloride is soluble in water. The washed gas is separated from the water, purified and circulated around the heating electrode 100. Preferably, the water containing impurities can also be recycled after appropriate treatment.

[0027] Alternatively, the gas washing unit 200 may be an alkali liquid circulation washing unit 220 using alkali liquid as a washing liquid. The alkali liquid may be an alkali liquid of any composition that can react with the impurity gas to achieve the purpose of purification. Taking sodium hydroxide solution as an example, it can react with carbon dioxide. When carbon dioxide is in a small amount, it can react with sodium hydroxide to generate sodium carbonate (2NaOH+CO2=Na2CO3+H2O); when carbon dioxide is in excess, it will further react to generate sodium bicarbonate. The generated carbonate substances such as sodium carbonate or sodium bicarbonate exist in the system. If the impurity gas contains chlorine, the chlorine will react with the water in the alkali liquid to generate hydrochloric acid and hypochlorous acid (Cl2+H2O=HCl+HClO), and the generated hydrochloric acid can react with the carbonate or bicarbonate generated by the previous reaction of the alkali liquid and carbon dioxide to undergo a double decomposition reaction, for example, react with sodium carbonate to generate sodium chloride, carbon dioxide and water (2HCl+Na2CO3=2NaCl+CO2↑+H2O). As a result, carbon dioxide and chlorine can be transferred to the alkali liquid by chemical reactions to achieve the purpose of purification.

[0028] In another embodiment of the present invention, Figure 2As shown, the gas washing unit 200 may include a water circulation washing unit 210 and an alkali liquid circulation washing unit 220 connected in series. The principle of purifying impurity gas by the water circulation washing unit 210 and the alkali liquid circulation washing unit 220 is not described in detail here. It should be understood that although Figure 2 It is shown that the impurity gas first flows through the water circulation washing unit 210 and then flows through the alkali liquid circulation washing unit 220. Alternatively, the staff can change the number and arrangement order of the water circulation washing unit 210 and the alkali liquid circulation washing unit 220 according to actual needs.

[0029] In another embodiment of the present invention, Figure 3 As shown, the gas washing unit 200 is a dual-purpose washing unit, comprising a water circulation washing unit 210 and an alkali liquid circulation washing unit 220 connected in parallel, the air inlet end of the water circulation washing unit 210 and the alkali liquid circulation washing unit 220 is provided with a first valve 340, and the air outlet end of the water circulation washing unit 210 and the alkali liquid circulation washing unit 220 is provided with a second valve 350. In this embodiment, the processing device further includes a detection unit 400. Among them, the detection unit 400 may include a first detection component 410 installed around the heating electrode 100, and the first detection component 410 is configured to detect the content of impurity gas around the heating electrode 100. The first valve 340 and the second valve 350 are connected to the first detection component 410 in communication, and are configured to connect the pipeline where the water circulation washing unit 210 is located in response to the content of the impurity gas meeting the preset condition, and connect the pipeline where the alkali liquid circulation washing unit 220 is located in response to the content of the impurity gas not meeting the preset condition. The staff can set the content of impurity gas to meet the preset conditions according to the on-site working conditions, such as but not limited to reducing the mass percentage of chlorine in the gas around the heating electrode 100 to below 10ppm. Thus, the dual-purpose washing unit can use only water to wash the gas around the heating electrode in the normal production state of the molten salt chlorination furnace, and can use only alkali liquid to circulate and wash the gas around the heating electrode in the abnormal state of the molten salt chlorination furnace and reduce the mass percentage of chlorine in the gas around the heating electrode after washing to below 10ppm.

[0030] Combination Figure 1-3As shown, in an embodiment including an alkali liquid circulation washing unit 220, the detection unit 400 may further include a second detection component 420 disposed in the alkali liquid circulation washing unit 220. The second detection component 420 is configured to detect the content of carbonate in the alkali liquid circulation washing unit 220. The staff can manually or automatically replace the alkali liquid based on the detection result of the second detection component 420. Preferably, the processing device also includes a control unit (not shown in the figure). The control unit is connected to the second detection component 420 for communication, and is configured to automatically replace the alkali liquid in response to the content of carbonate being higher than a set threshold. Specifically, the control unit replaces the first circulating liquid in the alkali liquid circulation washing unit 220 with a new alkali liquid according to the detection result of the second detection component 420 to ensure that the carbonate corresponding to the new alkali liquid is not deposited in the alkali liquid circulation washing unit. The staff can set a set threshold value according to the on-site working conditions to avoid the alkali liquid from completely reacting and affecting the purification effect.

[0031] According to another aspect of the present invention, a method for treating leakage of reaction medium around a heating electrode of a molten salt chlorination furnace is provided. The method requires setting a treatment device of any of the above embodiments at the heating electrode 100, and the treatment device circulates and washes the gas around the heating electrode 100 to achieve gas purification.

[0032] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0033] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A device for treating leakage of reaction medium around heating electrodes of a molten salt chlorination furnace, characterized in that: include: A gas washing unit (200) containing a washing liquid for washing impurity gases; The pipeline unit (300) comprises an air inlet pipeline (310), an air outlet pipeline (320), and an air extraction device (330) arranged on the air inlet pipeline (310) and / or the air outlet pipeline (320), wherein the gas around the heating electrode (100) is introduced into the gas washing unit (200) through the air inlet pipeline (310) for washing, and the washed gas is discharged to the vicinity of the heating electrode (100) through the air outlet pipeline (320).

2. The processing device according to claim 1, characterized in that The gas washing unit (200) is a water circulation washing unit (210), and the washing liquid is water.

3. The processing device according to claim 1, characterized in that The gas washing unit (200) is an alkaline solution circulation washing unit (220), and the washing liquid is alkaline solution.

4. The processing device according to claim 1, characterized in that The gas washing unit (200) comprises a water circulation washing unit (210) and an alkali solution circulation washing unit (220) connected in series.

5. The processing device according to claim 1, characterized in that The gas washing unit (200) is a dual-purpose washing unit, comprising a water circulation washing unit (210) and an alkali solution circulation washing unit (220) connected in parallel, wherein the air inlet ends of the water circulation washing unit (210) and the alkali solution circulation washing unit (220) are provided with a first valve (340), and the air outlet ends of the water circulation washing unit (210) and the alkali solution circulation washing unit (220) are provided with a second valve (350).

6. The processing device according to claim 5, characterized in that The processing device also includes: A detection unit (400) comprising a first detection component (410) installed around the heating electrode (100), the first detection component (410) being configured to detect the content of impurity gas around the heating electrode (100); The first valve (340) and the second valve (350) are connected to the first detection component (410) in communication, and are configured to connect the pipeline of the water circulation washing unit (210) in response to the content of the impurity gas meeting a preset condition, and to connect the pipeline of the alkali liquid circulation washing unit (220) in response to the content of the impurity gas not meeting the preset condition.

7. The processing device according to claim 6, characterized in that The content of the impurity gas meets the preset conditions including: The mass percentage content of chlorine gas in the gas around the heating electrode (100) is reduced to below 10 ppm.

8. The processing device according to any one of claims 3 to 7, characterized in that: The processing device also includes: The detection unit (400) comprises a second detection component (420) arranged in the alkali solution circulation washing unit (220), wherein the second detection component (420) is arranged to detect the content of carbonate in the alkali solution circulation washing unit (220).

9. The processing device according to claim 8, characterized in that The processing device also includes: A control unit is connected in communication with the second detection component (420) and is configured to replace the alkali solution in response to the carbonate content being higher than a set threshold.

10. A method for treating leakage of reaction medium around heating electrodes of a molten salt chlorination furnace, characterized in that: A processing device according to any one of claims 1 to 9 is arranged at the heating electrode (100).

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