Process for producing chlorine by using byproduct hydrogen chloride gas of Mannheim potassium sulfate

Abstract

The invention discloses a process for producing chlorine from a byproduct hydrogen chloride gas from Mannheim potassium sulfate, and relates to the technical field of chemical process optimization and resource recycling, and the process comprises the following steps: directly introducing the byproduct hydrogen chloride gas in the reaction process of a Mannheim reaction furnace into an oxidation reactor without external heating; the heat of the hydrogen chloride gas is directly utilized to carry out high-temperature oxidation reaction under the action of a catalyst to generate chlorine and water vapor. According to the invention, the problem of treatment of traditional byproduct hydrochloric acid is solved, the energy consumption of traditional chlorine production from hydrochloric acid is reduced, the integrated design of resource recovery and the device is realized, and the overall economic benefit and environmental friendliness are remarkably improved; according to the method, the high-temperature characteristic of the reaction tail gas is fully utilized, in-situ conversion chlorine preparation without absorption, storage and heating is realized, the treatment problem of the byproduct hydrogen chloride gas is effectively solved, and meanwhile, the chlorine preparation cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chemical process optimization and resource recycling, and particularly relates to a process for producing chlorine gas from hydrogen chloride gas by-produced in a Mannheim potassium sulfate production process. BACKGROUND

[0002] The Mannheim potassium sulfate production device is built with high-temperature-resistant refractory bricks, insulating bricks and common red bricks, and the top of the device is insulated with insulating bricks and asbestos. The reaction furnace has two cavities, an oval cavity in the middle serving as a reaction chamber, and a cavity serving as a combustion chamber. Sulfuric acid and potassium chloride are uniformly fed into the reaction chamber of the Mannheim furnace through a feeder, and the combustion chamber is provided with a combustion nozzle. The heat released by the fuel indirectly heats the reaction chamber. The cavity is provided with a stirring rake, which rotates at 1-2 r / min during the reaction to continuously mix and react the sulfuric acid and potassium chloride to produce potassium sulfate and hydrogen chloride gas. The potassium sulfate is pushed out by the stirring rake, and the hydrogen chloride gas is recycled. The sulfuric acid and potassium chloride are uniformly fed into the reaction chamber of the Mannheim furnace through the feeder, and the combustion chamber provides a large amount of heat energy for the materials reacting in the reaction chamber. Under the continuous stirring of the stirrer, the reaction materials, sulfuric acid and potassium chloride, absorb a large amount of heat to produce potassium sulfate and hydrogen chloride gas.

[0003] At present, the Mannheim potassium sulfate production device produces about 1.2 tons of 31% hydrochloric acid (or equivalent amount of hydrogen chloride gas) as by-products for every ton of potassium sulfate produced in the production process. These by-product hydrochloric acid is difficult to utilize locally due to high absorption, storage and transportation costs. The traditional approach is to produce calcium chloride and other low-value-added products, which results in energy waste and environmental burden. On the other hand, the traditional hydrochloric acid electrolysis method and the oxidation method for producing chlorine gas have high energy consumption and large investment. SUMMARY

[0004] The present application provides a process for producing chlorine gas from hydrogen chloride gas by-produced in a Mannheim potassium sulfate production process to solve the above problems.

[0005] To achieve the above-mentioned purpose, the technical solution of the present application is as follows: A process for producing chlorine gas from hydrogen chloride gas by-produced in a Mannheim potassium sulfate production process, the process comprising: The hydrogen chloride gas by-produced in the Mannheim reaction furnace reaction process is directly introduced into the oxidation reactor without external heating, and the heat of the hydrogen chloride gas itself is directly utilized to perform high-temperature oxidation reaction under the action of a catalyst to generate chlorine gas and water vapor.

[0006] In a preferred embodiment of the present application, the hydrogen chloride gas by-produced in the Mannheim reaction furnace reaction process is first introduced into a deacidifier to remove dust and mist before being introduced into the oxidation reactor.

[0007] In a preferred embodiment of the present application, the catalyst is CuCl2 or Al2O3 or RuO2 or Fe2O3.

[0008] In a preferred embodiment of the present application, after the generation of chlorine gas and water vapor, the water vapor is separated by condensation through a cooler to obtain high-purity chlorine gas.

[0009] In a preferred embodiment of the present application, the separated water vapor enters a tail gas absorption tower for treatment.

[0010] In a preferred embodiment of the present application, the high-purity chlorine gas is directly connected to a downstream chlorine product device to realize on-site consumption of chlorine gas.

[0011] In a preferred embodiment of the present application, the obtained high-purity chlorine gas can be input again into the oxidation reactor for further purification.

[0012] The beneficial effects of the present application are: The present application solves the problem of traditional by-product hydrochloric acid treatment, reduces the energy consumption of traditional hydrochloric acid chlorine production, realizes resource recycling and integrated design of the device, and significantly improves the overall economic benefit and environmental friendliness.

[0013] The present application fully utilizes the high-temperature characteristics of the reaction tail gas to realize on-site conversion of chlorine without absorption, storage, and heating, effectively solves the problem of by-product hydrogen chloride gas treatment, and reduces the cost of chlorine production.

[0014] The present application can be directly connected to a downstream chlorine product device to realize on-site consumption of chlorine gas, greatly improving the treatment efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0016] Figure 1 The process flow chart of the present application. DETAILED DESCRIPTION

[0017] In order to make the technical means, creative features, purposes and effects achieved by the present application easy to understand, the present application is further described below.

[0018] Referring to Figure 1 The present application provides a process for producing chlorine gas from by-product hydrogen chloride gas in a Mannheim potassium sulfate production process, which comprises: The hydrogen chloride gas by-produced in the reaction process of the Mannheim reaction furnace is directly introduced into the oxidation reactor, without external heating, and directly utilizes the heat of the hydrogen chloride gas itself to generate chlorine gas and water vapor under the action of a catalyst.

[0019] Since the hydrogen chloride gas by-produced in the reaction process of the Mannheim reaction furnace is in a high-temperature state, about 450℃, which is just suitable for the oxidation reaction, the present application directly introduces the hydrogen chloride gas by-produced in the Mannheim reaction furnace into the oxidation reactor for oxidation reaction, thus omitting the subsequent heating process and improving the work efficiency and saving energy consumption.

[0020] The oxidation reactor can directly generate chlorine gas and water vapor by inputting external air or oxygen into the oxidation reactor and then performing high-temperature oxidation reaction with the hydrogen chloride gas introduced into the oxidation reactor under the action of a catalyst.

[0021] In order to improve the oxidation efficiency, the oxidation reactor can be connected to a heat exchanger, and the oxygen or air is heated by the heat exchanger before being input into the oxidation reactor, and then performs high-temperature oxidation reaction with the hydrogen chloride gas under the action of a catalyst, thus preventing the temperature of the oxygen or air from being too low to affect the oxidation reaction.

[0022] The catalyst used in the present application is a common catalyst, which can be CuCl2 or Al2O3 or RuO2 or Fe2O3, or other catalysts, as long as it can make the hydrogen chloride gas perform high-temperature oxidation reaction.

[0023] The reaction of the high-temperature oxidation reaction is as follows: the conversion rate can reach 60-75% per pass, and the conversion rate is very high.

[0024]

[0025] In addition, before introducing the hydrogen chloride gas by-produced in the reaction process of the Mannheim reaction furnace into the oxidation reactor, it can first enter a deacidifier to remove dust and mist, and then be introduced into the oxidation reactor, which can further improve the reaction quality.

[0026] In the application, the oxidation reactor is also connected to a cooler, and the gas after the reaction of the oxidation reactor is condensed after passing through the cooler to separate out water vapor, and high-purity chlorine gas is obtained, improving the purity of the chlorine gas.

[0027] The present application also provides an optimized embodiment, and the present application can also recycle the heat of the water vapor and chlorine gas after the reaction, and the recycled heat can be directly fed back to the combustion chamber of the reaction furnace of the Mannheim potassium sulfate device for heating, reducing fuel consumption.

[0028] The separated water vapor can enter a tail gas absorption tower for treatment, facilitating subsequent recycling, such as: The condensed water treated by the absorption tower is purified and then used as a raw material of the Mannheim furnace reaction (e.g., to prepare dilute sulfuric acid), thereby reducing fresh water consumption.

[0029] In the application, the obtained high-purity chlorine gas can be directly connected to a downstream chlorine product device, such as sodium hypochlorite, which is a high-value-added product using chlorine gas as a raw material, to realize on-site consumption of chlorine gas, save other intermediate links, and improve efficiency.

[0030] In addition, the chlorine gas obtained after condensation by the cooler can be introduced into the oxidation reactor again for further purification until the required purity is reached, and then be recycled or directly connected to a downstream chlorine product device.

[0031] In addition, the application produces hydrogen chloride gas during the reaction of the Mannheim reaction furnace of the potassium sulfate device, which is converted into chlorine gas mixture under the condition of a catalyst, wherein the chlorine content is 50% to 60%, the oxygen content is 20% to 25%, and the remaining part is nitrogen. Now these mixed gases can be used to produce bromine under certain conditions, which can be directly sold. This process reduces the cost of hydrochloric acid purification device and converts hydrogen chloride into more valuable bromine.

[0032] It is necessary to explain that the oxidation reaction of hydrogen chloride gas in the oxidation reactor to produce hydrogen is a conventional technology in the field, but the application directly matches the Mannheim potassium sulfate device, directly introduces the hydrogen chloride gas generated by the Mannheim potassium sulfate device at high temperature into the oxidation reactor, uses the temperature suitable for oxidation reaction of the hydrogen chloride gas, directly performs oxidation reaction on site, and directly connects the obtained hydrogen to the downstream chlorine product device to realize on-site consumption of chlorine gas. This implementation is obtained by the application of creative labor.

[0033] Through the implementation of the application, chlorine can be directly converted on site without absorption, storage, and heating, effectively solving the problem of processing hydrogen chloride gas by-product of the Mannheim potassium sulfate device, reducing the cost of chlorine production, improving the overall economy and environmental friendliness of the system, and reducing the cost of chlorine production.

[0034] The above shows and describes the basic principles and main features of the application and the advantages of the application. Those skilled in the art should understand that the application is not limited to the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the application. Without departing from the spirit and scope of the application, various changes and improvements can be made to the application, and these changes and improvements all fall within the scope of the claimed application. The scope of protection of the application is defined by the appended claims and their equivalents.

Claims

1. A process for the production of chlorine gas from the by-product hydrogen chloride gas of the Mannheim potassium sulfate process, characterized in that, The process comprises: The hydrogen chloride gas by-produced in the reaction process of the Mannheim reaction furnace is directly introduced into the oxidation reactor, without external heating, and directly utilizes the heat of the hydrogen chloride gas itself to generate chlorine and water vapor under the action of a catalyst.

2. A process for the production of chlorine gas from the by-product hydrogen chloride gas from the production of potassium sulfate by the Mannheim process according to claim 1, characterized in that, The hydrogen chloride gas by-produced in the reaction process of the Mannheim reaction furnace is first introduced into a deacidifier to remove dust and mist before being introduced into the oxidation reactor.

3. A process for the production of chlorine gas from the by-product hydrogen chloride gas of the production of potassium sulfate by the Mannheim process according to claim 1, characterized in that, The catalyst is CuCl2 or Al2O3 or RuO2 or Fe2O3.

4. A process for the production of chlorine gas from the by-product hydrogen chloride gas from the production of potassium sulfate by the Mannheim process as claimed in claim 1, characterized in that, After the generation of chlorine and water vapor, the water vapor is separated by a condenser to obtain high-purity chlorine.

5. A process for the production of chlorine gas from the by-product hydrogen chloride gas from the production of potassium sulfate by the Mannheim process as claimed in claim 4, characterized in that, The separated water vapor is introduced into a tail gas absorption tower for treatment.

6. A process for the production of chlorine gas from the by-product hydrogen chloride gas from the production of potassium sulfate by the Mannheim process as claimed in claim 4, characterized in that, The high-purity chlorine is directly connected to a downstream chlorine product device to realize on-site consumption of the chlorine.

7. A process for the production of chlorine gas from the by-product hydrogen chloride gas from the production of potassium sulfate by the Mannheim process as claimed in claim 4, characterized in that, The obtained high-purity chlorine can be input into the oxidation reactor again for further purification.

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