CN112250089A - Method for producing sodium metabisulfite by utilizing sulfur-containing tail gas - Google Patents
Method for producing sodium metabisulfite by utilizing sulfur-containing tail gas Download PDFInfo
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- CN112250089A CN112250089A CN202011180421.9A CN202011180421A CN112250089A CN 112250089 A CN112250089 A CN 112250089A CN 202011180421 A CN202011180421 A CN 202011180421A CN 112250089 A CN112250089 A CN 112250089A
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- sulfur
- tail gas
- containing tail
- sodium metabisulfite
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
- C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
- C01D5/14—Preparation of sulfites
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
- Y02P20/129—Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
Abstract
The application discloses a method for producing sodium metabisulfite by utilizing sulfur-containing tail gas, which comprises the following steps: burning the sulfur-containing tail gas at the temperature of 550-750 ℃; dedusting the burnt sulfur-containing tail gas, and adsorbing sulfur dioxide by using active carbon; desorbing the activated carbon after absorbing the sulfur dioxide at the temperature of 400-500 ℃ to discharge gas; and introducing gas discharged from the activated carbon into a saturated sodium bisulfite solution to generate sodium metabisulfite crystals. The method for producing the sodium metabisulfite by utilizing the sulfur-containing tail gas provided by the application converts sulfur in the tail gas into sodium metabisulfite crystals through the steps of burning, dedusting, adsorbing, desorbing and saturating sodium bisulfite solution, thereby not only being beneficial to environmental protection, but also leading sulfide to be recycled.
Description
Technical Field
The application relates to the technical field of chemical processes, in particular to a method for producing sodium metabisulfite by utilizing sulfur-containing tail gas.
Background
Sulfur dioxide (SO)2) Is one of the main pollutants in the atmosphere, can cause the damage of respiratory organs and has great influence on the health of human bodies. Sulfur dioxide is emitted in various production processes such as fossil fuel combustion, roasting of sulfur-containing ores, and smelting and chemical production. Therefore, controlling the emission of sulfur dioxide and reducing the environmental pollution are important issues to be solved.
In order to control the emission of sulfur dioxide, it is necessary to remove the sulfur from the tail gas. The existing method is to prepare the removed sulfur into calcium sulfate for utilization, but has the defects that the quality of gypsum is difficult to ensure and secondary pollution is easy to cause.
Therefore, how to remove the sulfur in the tail gas and recycle the sulfur into resources is a technical problem to be solved urgently by the technical personnel in the field.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide a method for producing sodium metabisulfite by utilizing sulfur-containing tail gas; the method for producing the sodium metabisulfite by utilizing the sulfur-containing tail gas provided by the application converts sulfur in the tail gas into sodium metabisulfite crystals through the steps of burning, dedusting, adsorbing, desorbing and saturating sodium bisulfite solution, thereby not only being beneficial to environmental protection, but also leading sulfide to be recycled.
The technical scheme provided by the invention is as follows:
a method for producing sodium metabisulfite by utilizing sulfur-containing tail gas comprises the following steps:
burning the sulfur-containing tail gas at the temperature of 550-750 ℃;
dedusting the burnt sulfur-containing tail gas, and adsorbing sulfur dioxide by using active carbon;
desorbing the activated carbon after absorbing the sulfur dioxide at the temperature of 400-500 ℃ to discharge gas;
and introducing gas discharged from the activated carbon into a saturated sodium bisulfite solution to generate sodium metabisulfite crystals.
Preferably, the burned sulfur-containing tail gas is subjected to waste heat utilization and temperature reduction and then is dedusted.
Preferably, the burned sulfur-containing tail gas is introduced into a waste heat utilization pipeline for heat exchange, and dust is removed after temperature reduction.
Preferably, a cyclone is used for dust removal.
Preferably, the saturated sodium bisulfite solution is prepared by desorbing the vented gas with activated carbon and reacting with a sodium carbonate solution.
Preferably, the method further comprises the following steps: and introducing gas discharged by the activated carbon into a saturated sodium bisulfite solution to generate gas during reaction, and pressurizing and cooling to obtain liquefied carbon dioxide.
Preferably, the sodium metabisulfite crystals obtained are dried to form powder and packaged.
The application provides a method for producing sodium metabisulfite by utilizing sulfur-containing tail gas, which converts sulfur in the tail gas into sodium metabisulfite crystals through the steps of burning, dedusting, adsorbing, desorbing and saturating sodium bisulfite solution, thereby not only being beneficial to environmental protection, but also leading sulfide to be recycled.
According to the method for producing sodium metabisulfite from sulfur-containing tail gas, firstly, sulfur-containing components (hydrogen sulfide, carbon disulfide and the like) in the tail gas react with oxygen to be converted into sulfur dioxide through firing, and after dust removal, activated carbon is used for adsorbing the sulfur dioxide. The sulfur content of the gas adsorbed by the activated carbon is reduced to the emission standard, the activated carbon adsorbing the sulfur dioxide can discharge the adsorbed sulfur dioxide under the heating condition of 400-500 ℃, and the desorbed activated carbon can be recycled. Meanwhile, the content of sulfur dioxide in the gas discharged by the activated carbon is higher, so that the subsequent reaction is facilitated to generate sodium metabisulfite, and the production efficiency is improved.
At present, the application field and the use amount of sodium metabisulfite are rapidly increased, and the market demand of sodium metabisulfite is vigorous. The sulfur in the tail gas is used for preparing the sodium metabisulfite, so that the market demand can be met, the production cost can be reduced, and the effect of reducing the environmental pollution can be achieved.
Detailed Description
The embodiments of the present application are written in a progressive manner.
The embodiment of the invention provides a method for producing sodium metabisulfite by utilizing sulfur-containing tail gas, which comprises the following steps:
burning the sulfur-containing tail gas at the temperature of 550-750 ℃;
dedusting the burnt sulfur-containing tail gas, and adsorbing sulfur dioxide by using active carbon;
desorbing the activated carbon after absorbing the sulfur dioxide at the temperature of 400-500 ℃ to discharge gas;
and introducing gas discharged from the activated carbon into a saturated sodium bisulfite solution to generate sodium metabisulfite crystals.
The application provides a method for producing sodium metabisulfite by utilizing sulfur-containing tail gas, which converts sulfur in the tail gas into sodium metabisulfite crystals through the steps of burning, dedusting, adsorbing, desorbing and saturating sodium bisulfite solution, thereby not only being beneficial to environmental protection, but also leading sulfide to be recycled.
According to the method for producing sodium metabisulfite from sulfur-containing tail gas, firstly, sulfur-containing components (hydrogen sulfide, carbon disulfide and the like) in the tail gas react with oxygen to be converted into sulfur dioxide through firing, and after dust removal, activated carbon is used for adsorbing the sulfur dioxide. The sulfur content of the gas adsorbed by the activated carbon is reduced to the emission standard, the activated carbon adsorbing the sulfur dioxide can discharge the adsorbed sulfur dioxide under the heating condition of 400-500 ℃, and the desorbed activated carbon can be recycled. Meanwhile, the content of sulfur dioxide in the gas discharged by the activated carbon is higher, so that the subsequent reaction is facilitated to generate sodium metabisulfite, and the production efficiency is improved.
At present, the application field and the use amount of sodium metabisulfite are rapidly increased, and the market demand of sodium metabisulfite is vigorous. The sulfur in the tail gas is used for preparing the sodium metabisulfite, so that the market demand can be met, the production cost can be reduced, and the effect of reducing the environmental pollution can be achieved.
Preferably, the burned sulfur-containing tail gas is subjected to waste heat utilization and temperature reduction and then is dedusted.
Preferably, the burned sulfur-containing tail gas is introduced into a waste heat utilization pipeline for heat exchange, and dust is removed after temperature reduction.
The burning process needs to be carried out at the temperature of more than 550 ℃, so the temperature of the sulfur-containing tail gas obtained after burning is higher, the requirements on equipment for direct dust removal and activated carbon adsorption are higher, and the heat contained in the tail gas cannot be fully utilized. Therefore, it is preferable to use the residual heat of the burned sulfur-containing tail gas, cool the tail gas, and remove dust. The preferable waste heat utilization mode is to introduce the sulfur-containing tail gas into a waste heat utilization pipeline, perform heat exchange in process equipment needing heat energy without directly contacting with the outside, and avoid the pollution caused by substances in the tail gas or the influence on other processes.
Preferably, a cyclone is used for dust removal.
Preferably, the saturated sodium bisulfite solution is prepared by desorbing the vented gas with activated carbon and reacting with a sodium carbonate solution.
A saturated sodium bisulfite solution, preferably prepared by reacting the effluent gas from activated carbon desorption (containing mainly sulfur dioxide) with a sodium carbonate solution. The sodium carbonate is easy to purchase and configure, after the sodium carbonate solution is configured in the initial stage of sodium metabisulfite production, the sulfur dioxide gas generated continuously is used for reaction to prepare saturated sodium bisulfite solution, and the sodium carbonate is supplemented if necessary.
Preferably, the method further comprises the following steps: and introducing gas discharged by the activated carbon into a saturated sodium bisulfite solution to generate gas during reaction, and pressurizing and cooling to obtain liquefied carbon dioxide.
In the reaction process of sodium carbonate and sulfur dioxide, a large amount of carbon dioxide gas can be produced, and the carbon dioxide gas is directly discharged to cause resource waste. Therefore, it is preferable to collect the gas generated by the reaction, and after pressurization and temperature reduction, the carbon dioxide is liquefied, while other gases are still in a gaseous state, and the liquefied carbon dioxide can be separated by collecting. The carbon dioxide can be used for preparing carbonate products.
Preferably, the sodium metabisulfite crystals obtained are dried to form powder and packaged.
The obtained sodium pyrosulfite crystal is dried and dehydrated to be made into powder, and the powder is packaged and stored.
Example 1
A method for producing sodium metabisulfite by utilizing sulfur-containing tail gas comprises the following steps:
burning the sulfur-containing tail gas at 700 ℃;
introducing the burnt sulfur-containing tail gas into a waste heat utilization pipeline, carrying out heat exchange, cooling, dedusting by using a cyclone separator, and adsorbing sulfur dioxide by using activated carbon;
desorbing the activated carbon adsorbed with sulfur dioxide at 450 ℃ to discharge gas;
introducing gas discharged from the activated carbon into a saturated sodium bisulfite solution to generate sodium metabisulfite crystals, drying to prepare powder, and packaging; and meanwhile, the generated gas is pressurized and cooled to obtain liquefied carbon dioxide for collection and utilization.
Wherein, the saturated sodium bisulfite solution is prepared by desorbing discharged gas by activated carbon and reacting with a sodium carbonate solution.
Example 2
A method for producing sodium metabisulfite by utilizing sulfur-containing tail gas comprises the following steps:
burning the sulfur-containing tail gas at 550 ℃;
introducing the burnt sulfur-containing tail gas into a waste heat utilization pipeline, carrying out heat exchange, cooling, dedusting by using a cyclone separator, and adsorbing sulfur dioxide by using activated carbon;
desorbing the activated carbon adsorbed with sulfur dioxide at 400 ℃ to discharge gas;
introducing gas discharged from the activated carbon into a saturated sodium bisulfite solution to generate sodium metabisulfite crystals, drying to prepare powder, and packaging; and meanwhile, the generated gas is pressurized and cooled to obtain liquefied carbon dioxide for collection and utilization.
Wherein, the saturated sodium bisulfite solution is prepared by desorbing discharged gas by activated carbon and reacting with a sodium carbonate solution.
Example 3
A method for producing sodium metabisulfite by utilizing sulfur-containing tail gas comprises the following steps:
burning the sulfur-containing tail gas at 650 ℃;
introducing the burnt sulfur-containing tail gas into a waste heat utilization pipeline, carrying out heat exchange, cooling, dedusting by using a cyclone separator, and adsorbing sulfur dioxide by using activated carbon;
desorbing the activated carbon adsorbed with sulfur dioxide at 500 ℃ to discharge gas;
introducing gas discharged from the activated carbon into a saturated sodium bisulfite solution to generate sodium metabisulfite crystals, drying to prepare powder, and packaging; and meanwhile, the generated gas is pressurized and cooled to obtain liquefied carbon dioxide for collection and utilization.
Wherein, the saturated sodium bisulfite solution is prepared by desorbing discharged gas by activated carbon and reacting with a sodium carbonate solution.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (7)
1. A method for producing sodium metabisulfite by utilizing sulfur-containing tail gas is characterized by comprising the following steps:
burning the sulfur-containing tail gas at the temperature of 550-750 ℃;
dedusting the burnt sulfur-containing tail gas, and adsorbing sulfur dioxide by using active carbon;
desorbing the activated carbon after absorbing the sulfur dioxide at the temperature of 400-500 ℃ to discharge gas;
and introducing gas discharged from the activated carbon into a saturated sodium bisulfite solution to generate sodium metabisulfite crystals.
2. The method for producing sodium metabisulfite from sulfur-containing tail gas as recited in claim 1, wherein the burned sulfur-containing tail gas is subjected to waste heat utilization, temperature reduction and then dust removal.
3. The method for producing sodium metabisulfite using sulfur-containing tail gas as claimed in claim 2, wherein the burned sulfur-containing tail gas is introduced into a waste heat utilization pipeline for heat exchange, and dust removal is performed after temperature reduction.
4. The method for producing sodium metabisulfite using sulfur-containing tail gas as set forth in any one of claims 1 to 3, characterized in that a cyclone is used for dust removal.
5. The method for producing sodium metabisulfite using sulfur-containing tail gas according to claim 1, wherein the saturated sodium bisulfite solution is prepared by desorbing discharged gas with activated carbon and reacting with sodium carbonate solution.
6. The method for producing sodium metabisulfite from sulfur-containing tail gas as claimed in claim 1, further comprising the steps of: and introducing gas discharged by the activated carbon into a saturated sodium bisulfite solution to generate gas during reaction, and pressurizing and cooling to obtain liquefied carbon dioxide.
7. The method for producing sodium metabisulfite using sulfur-containing tail gas as claimed in claim 1, wherein the obtained sodium metabisulfite crystals are dried, powdered and packaged.
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| CN202011180421.9A CN112250089A (en) | 2020-10-29 | 2020-10-29 | Method for producing sodium metabisulfite by utilizing sulfur-containing tail gas |
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| CN202011180421.9A CN112250089A (en) | 2020-10-29 | 2020-10-29 | Method for producing sodium metabisulfite by utilizing sulfur-containing tail gas |
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| CN110743344A (en) * | 2019-10-10 | 2020-02-04 | 株洲三特环保节能股份有限公司 | Method for removing low-concentration sulfur dioxide in flue gas and preparing sodium metabisulfite |
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2020
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Patent Citations (14)
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| US5976485A (en) * | 1996-10-07 | 1999-11-02 | Solvay Minerals, Inc. | Sodium metabisulfite process |
| CN1356261A (en) * | 2001-10-16 | 2002-07-03 | 广东中成化工有限公司 | Process for recovering food-class CO2 by adding alkaline tail gas to mother liquid of sodium salt of pyrosulfurous acid |
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