CN108557775B - Tail gas treatment method in chlorosulfonic acid preparation process, system for implementing method and chlorosulfonic acid preparation method - Google Patents
Tail gas treatment method in chlorosulfonic acid preparation process, system for implementing method and chlorosulfonic acid preparation method Download PDFInfo
- Publication number
- CN108557775B CN108557775B CN201810632199.8A CN201810632199A CN108557775B CN 108557775 B CN108557775 B CN 108557775B CN 201810632199 A CN201810632199 A CN 201810632199A CN 108557775 B CN108557775 B CN 108557775B
- Authority
- CN
- China
- Prior art keywords
- gas
- tail gas
- chlorosulfonic acid
- acid
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/46—Compounds containing sulfur, halogen, hydrogen, and oxygen
- C01B17/466—Chlorosulfonic acid (ClSO3H)
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B17/00—Sulfur; Compounds thereof
- C01B17/69—Sulfur trioxide; Sulfuric acid
- C01B17/74—Preparation
- C01B17/76—Preparation by contact processes
- C01B17/775—Liquid phase contacting processes or wet catalysis processes
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/01—Chlorine; Hydrogen chloride
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
Abstract
The invention provides a tail gas treatment method in a chlorosulfonic acid preparation process, a system for implementing the method and a chlorosulfonic acid preparation method. The tail gas treatment method comprises the following steps: acid washing step: absorbing SO in the tail gas by using an absorbent3A gas; and (3) water washing: absorbing HCl gas in the tail gas by using water to obtain hydrochloric acid; and (3) drying: drying the SO in the tail gas by using a drying agent2A gas. The tail gas generated in the preparation process of the chlorosulfonic acid is fully recycled by using a proper absorption and conversion treatment mode without alkali liquor absorption, so that only chlorosulfonic acid, hydrochloric acid and sulfuric acid are generated in the whole process, no waste water and waste gas are generated, resources are saved, and the environment is protected.
Description
Technical Field
The invention relates to a tail gas treatment method in a chlorosulfonic acid preparation process, a system for implementing the method and a chlorosulfonic acid preparation method, and belongs to the technical field of chemical processes.
Background
Chlorosulfonic acid is an important inorganic acid, and is mainly used for sulfonation of organic compounds, preparation of sulfonamides and saccharin, as a sulfonating agent of dye intermediates, preparation of pesticides, detergents, ion exchange resins, plastics and the like, and is used as a smoke screen agent in military.
Chlorosulfonic acid is produced by drying HCl gas and SO3The gas is used as raw material, and is made through synthetic reaction in a synthetic tower and an auxiliary tower, and then is condensed through cold separation. The synthesis process is a continuous processIn the process, the gas quantity is often unstable, SO HCl gas and SO are caused3The proportion of the gas is deviated, and the tail gas still contains a large amount of SO3、SO2And acid gases such as HCl and the like are absorbed by alkali liquor in order to protect the environment and achieve standard emission.
After the tail gas is absorbed by the alkali liquor, salt-containing mixtures such as sulfate, sulfite, chloride and the like can be obtained. The mixture of salts is then separated. However, since the salt mixture is not easily separated, it is generally disposed of. Or recycling part of tail gas to produce hydrochloric acid, and absorbing the rest with alkali liquor to obtain a salt-containing mixture, treating and discharging. However, the prepared salt mixture has low purity of a single salt component, so that tail gas cannot be recycled sufficiently, and a large amount of waste water is generated, thereby causing resource waste.
Patent application CN106800276A discloses an industrial production method for gas-phase synthesis of chlorosulfonic acid by using pure sulfur trioxide, which comprises a, using SO in a first conversion flue gas3Preparing 40% fuming sulfuric acid; b. evaporation to prepare pure product SO3A gas; c. desorbing hydrochloric acid to prepare pure HCl; d. using HCl gas and pure SO3Gas synthesis of rental chlorosulfonic acid; e. refining chlorosulfonic acid; and f, treating tail gas and the like. The method needs to obtain pure sulfur trioxide, and has the disadvantages of complex preparation method, high obtaining difficulty and high required cost.
Disclosure of Invention
Problems to be solved by the invention
The invention aims to provide a tail gas treatment method in a chlorosulfonic acid preparation process, a system for implementing the method and a chlorosulfonic acid preparation method. The tail gas generated in the preparation process of the chlorosulfonic acid is treated by proper absorption and conversion, and the byproducts are hydrochloric acid and sulfuric acid, so that zero emission of the tail gas can be realized, certain economic benefit and environmental protection benefit are realized, and the requirements of green chemical industry are met.
Furthermore, through proper technological conditions and reasonable measures, the resources in all the working procedures are fully utilized, and the chlorosulfonic acid with high concentration is produced.
Means for solving the problems
The invention provides a tail gas treatment method in a chlorosulfonic acid preparation process, which comprises the following steps:
acid washing step: absorbing SO in the tail gas by using an absorbent3A gas;
and (3) water washing: absorbing HCl gas in the tail gas by using water to obtain hydrochloric acid;
and (3) drying: drying the SO in the tail gas by using a drying agent2A gas.
The method for treating tail gas in the chlorosulfonic acid preparation process has the advantage that the concentration of hydrochloric acid obtained in the water washing step is 28-34%, preferably 28-32%.
The tail gas treatment method in the chlorosulfonic acid preparation process is characterized in that the temperature of the acid washing step is below 70 ℃; the absorbent comprises sulfuric acid, preferably, the concentration of the sulfuric acid is 93-100%, preferably 97.5-98.5%.
The tail gas treatment method in the chlorosulfonic acid preparation process is characterized in that the temperature of the drying step is below 70 ℃; the drying agent comprises sulfuric acid, preferably the concentration of the sulfuric acid is 93-100%, preferably 97.5-98.5%.
The tail gas treatment method in the chlorosulfonic acid preparation process, disclosed by the invention, further comprises the following steps of:
a conversion step: under the action of a catalyst, SO in the dried tail gas2Conversion of gas to SO3Gas to obtain SO-containing gas3The tail gas of (2).
The method for treating tail gas in the chlorosulfonic acid production process according to the present invention, wherein the temperature of the conversion step is controlled to be 380 to 450 ℃, preferably 400 to 420 ℃.
The method for treating tail gas in the chlorosulfonic acid production process according to the present invention is characterized in that the SO-containing gas obtained in the chlorosulfonic acid production process is used after the drying step and before the conversion step3The dried tail gas is preheated by the gas mixture of (1), whereinSaid SO containing3The temperature of the gas mixture of (a) is between 400 and 500 ℃, preferably between 420 and 480 ℃;
after preheating, contains SO3The temperature of the gas mixture of (a) is between 150 and 200 ℃; the temperature of the preheated tail gas is between 250 and 350 ℃.
The tail gas treatment method in the chlorosulfonic acid preparation process further comprises the following steps:
using said SO-containing3The tail gas exchanges heat with the preheated tail gas of the next batch; preferably, the temperature of the tail gas after heat exchange is between 340 and 430 ℃, preferably between 370 and 400 ℃.
The invention also provides a preparation method of chlorosulfonic acid, which comprises the following steps:
HCl gas preparation step: resolving hydrochloric acid to generate HCl gas;
SO3a gas preparation step: the SO-containing gas generated after burning the sulfur is converted and produced by a catalyst3The gas mixture of (a);
chlorosulfonic acid preparation step: reacting said HCl gas with said SO3Mixing the gas mixture to obtain chlorosulfonic acid gas;
and (3) tail gas treatment: the tail gas is treated according to the tail gas treatment method.
According to the method for preparing chlorosulfonic acid of the present invention, the chlorosulfonic acid preparation step further comprises:
and (3) cooling: cooling the chlorosulfonic acid gas;
and (3) a recovery step: reacting unreacted HCl gas with the SO-containing gas3Recovering the gas mixture of (1).
The method for preparing chlorosulfonic acid according to the present invention, wherein the SO is3SO-containing gas obtained in the gas preparation step3In the gas mixture of (3), SO38-11% of SO2The content is 0.5-2%;
preferably, the SO-containing3The temperature of the gas mixture of (a) is between 400 and 500 ℃, preferably between 420 and 480 ℃.
The present invention also provides a system for implementing a method for treating tail gas in a chlorosulfonic acid production process according to the present invention, comprising:
an acid wash tower that utilizes an absorbent to absorb SO in the tail gas3A gas;
a water scrubber for absorbing HCl gas in the tail gas with water to obtain hydrochloric acid;
a drying tower that dries SO in the tail gas using a desiccant2A gas.
The system according to the invention, wherein the system further comprises:
a converter for converting SO in the dried tail gas2Conversion of gas to SO3A gas.
The system according to the invention, wherein the system further comprises: one or the combination of more than two of a preheater, a heat exchanger, a heater, an economizer and an absorption tower.
The system according to the present invention, wherein the apparatus for preparing chlorosulfonic acid comprises:
a hydrochloric acid analysis device for analyzing the hydrochloric acid to generate HCl gas;
a sulfuric acid production device, which is used for converting furnace gas generated after burning sulfur into SO-containing gas by using a catalyst3The gas mixture of (a);
a chlorosulfonic acid production unit for reacting the HCl gas with the SO-containing gas3Mixing the gas mixture to obtain chlorosulfonic acid gas.
According to the system of the present invention, the chlorosulfonic acid production apparatus comprises: a synthesis column, a cold separation column and an auxiliary column, wherein
The synthesis tower is used for mixing the HCl gas and the SO-containing gas3Mixing the gas mixture to obtain chlorosulfonic acid gas;
the cold separation tower is used for cooling the obtained chlorosulfonic acid gas;
the auxiliary tower is used for mixing the unreacted HCl gas and the SO-containing gas3Recovering the gas mixture of (1).
ADVANTAGEOUS EFFECTS OF INVENTION
The tail gas generated in the preparation process of the chlorosulfonic acid is fully recycled by using a proper absorption and conversion treatment mode without alkali liquor absorption, so that only chlorosulfonic acid, hydrochloric acid and sulfuric acid are generated in the whole process, no waste water and waste gas are generated, resources are saved, and the environment is protected.
Furthermore, through proper process conditions and reasonable measures, resources among all the working procedures are fully utilized.
Further, SO3The heat in the gas conversion process can be fully utilized, external heat supply is not needed for preheating before tail gas conversion, and energy consumption is saved.
Drawings
Fig. 1 shows a flow chart of a process for preparing chlorosulfonic acid and treating tail gas in example 1 of the present invention.
Detailed Description
Various exemplary embodiments, features and aspects of the invention will be described in detail below. The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.
Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a better understanding of the present invention. It will be understood by those skilled in the art that the present invention may be practiced without some of these specific details. In other instances, methods, means, devices and steps which are well known to those skilled in the art have not been described in detail so as not to obscure the invention.
<First embodiment>
A first embodiment of the present invention provides a method for treating tail gas from a chlorosulfonic acid production process, comprising the steps of:
acid washing step: absorbing SO in the tail gas by using an absorbent3A gas;
and (3) water washing: absorbing HCl gas in the tail gas by using water to obtain hydrochloric acid;
and (3) drying: drying the tail with a desiccantSO in gas2And (5) gas, and obtaining dry tail gas.
In the present invention, the tail gas contains unreacted SO3Unreacted HCl and unreacted SO2In addition, the tail gas may also contain other gas components that may be present, such as air and the like. In the present invention, the acid washing step and the drying step may be performed in the same reactor, or may be performed in different reactors, for example: it can be carried out in a drying column or an acid washing column, respectively.
According to the method for treating the tail gas in the chlorosulfonic acid preparation process, the concentration of the hydrochloric acid obtained in the water washing step is 28-34%, and preferably 28-32%. The hydrochloric acid prepared during tail gas treatment can be reused in the HCl gas preparation step for hydrochloric acid resolution, so that HCl gas is prepared.
In the acid washing step of the present invention, the absorbent may be sulfuric acid, the concentration of the sulfuric acid may be 93% to 100%, preferably, the concentration of the sulfuric acid may be 97.5% to 98.5%, and the temperature of the acid washing step is below 70 ℃, preferably 55 to 65 ℃. In addition, in the drying step of the present invention, the drying agent may also be sulfuric acid, and the concentration of the sulfuric acid may also be 93% to 100%, preferably, the concentration of the sulfuric acid may be 97.5% to 98.5%; the temperature of the drying step is below 70 ℃, preferably 55-65 ℃.
According to the method for treating the tail gas in the chlorosulfonic acid preparation process, the drying step further comprises the following steps: a conversion step: under the action of a catalyst, SO in the dried tail gas2Conversion of gas to SO3Gas, thereby obtaining SO-containing3The tail gas of (2). The catalyst may be a vanadium catalyst, such as vanadium pentoxide, or the like. The obtained SO-containing3The tail gas can be reused to absorb SO in the tail gas by an absorbent3The gas is then recycled to the sulfuric acid production plant to produce chlorosulfonic acid. Generally, SO-containing products obtained by conversion in a converter3The temperature of the tail gas is 440-480 ℃.
In general, in the preparation of chlorosulfonic acid, SO is prepared3When the gas is used, the temperature can be generally between 400 and 500 DEG CPreferably between 420 and 480 ℃ in the presence of SO3The gas mixture of (1). The temperature range can be utilized3The gas mixture of (2) is subjected to a preheating treatment of the tail gas after the drying step and before the conversion step. Thereby making SO contained3The temperature of the gas mixture is reduced to 150-200 ℃ to facilitate the preparation of chlorosulfonic acid gas; and the temperature of the off-gas after the drying step and before the reforming step can be raised to between 250 and 350 c, preferably between 290 and 320 c, thereby facilitating the reforming step.
By using a gas containing SO3The gas mixture of (a) is subjected to a preheating treatment of the tail gas after the drying step and before the conversion step, SO that SO is obtained3The heat of the gas in the conversion process can be fully utilized, so that the energy can be further saved.
After preheating, the preheated tail gas can be subjected to heat exchange treatment again, and the SO-containing gas obtained after the last batch of tail gas is converted by the conversion step can be utilized3The tail gas is subjected to heat exchange. Generally, the preheated tail gas can be heat exchanged to 340-430 deg.C, and preferably, to 370-400 deg.C. The heating process does not adopt external heat supply, so that the energy consumption can be saved.
After heat exchange, the tail gas after the drying step and before the conversion step can be heated by a heater (an electric heating wire). And then heating the temperature of the tail gas after the drying step and before the conversion step to 380-450 ℃, preferably heating the temperature of the tail gas after the drying step and before the conversion step to 400-420 ℃.
According to the method for treating the tail gas in the chlorosulfonic acid preparation process, the SO contained in the tail gas obtained in the conversion step3After heat exchange, the tail gas contains SO3The temperature of the tail gas is reduced, generally between 380 and 400 ℃, and an economizer can be further utilized to reduce SO content3For example, to a temperature of 150-190 ℃. Further, an acid washing step (also referred to as an absorption step) may be further performed, that is: absorbing the converted SO with an absorbent3A gas. In the acid washing step, the absorbent preferably comprises sulfuric acid, the concentration of the sulfuric acid used is 93% -100%, preferably, the concentration of the sulfuric acid is 97.5% -98.5%; the temperature of the acid washing step is controlled below 70 ℃, preferably 55-65 ℃, and in the acid washing step, cross-flow absorption can be carried out by spraying an absorbent.
In the present invention, the finally produced sulfuric acid can be reused in the present invention for drying of HCl gas, an acid washing step in a tail gas recovery step, a drying step, a conversion step, and the like. In the tail gas recovery step of the present invention, the sulfuric acid in the drying step, the acid washing step and the conversion step may be used as needed, and the sulfuric acid may not be generated as waste sulfuric acid or may not be externally supplemented.
The tail gas treatment method in the chlorosulfonic acid preparation process can prepare sulfuric acid and hydrochloric acid for reuse in the chlorosulfonic acid preparation process.
< second embodiment >
A second embodiment of the present invention provides a method for preparing chlorosulfonic acid, comprising the steps of:
HCl gas preparation step: resolving hydrochloric acid to generate HCl gas;
SO3a gas preparation step: the SO-containing gas generated after burning the sulfur is converted and produced by a catalyst3The gas mixture of (a);
chlorosulfonic acid preparation step: reacting said HCl gas with said SO3Mixing the gas mixture to obtain chlorosulfonic acid gas;
and (3) tail gas treatment: the tail gas is treated according to the tail gas treatment method.
In the invention, hydrochloric acid analysis can be any existing analysis method, for example, the hydrochloric acid analysis can be carried out by a process of continuous contact countercurrent mass transfer and heat transfer of concentrated hydrochloric acid and high-temperature HCl gas heated by a reboiler and water vapor in a low-pressure high-temperature analysis tower, the concentrated hydrochloric acid descends along the surface of a filler by gravity and contacts with ascending gas, so that the content of the HCl gas in the ascending gas is increased continuously, the HCl gas containing saturated water is obtained at the top of the tower, the HCl gas is obtained by normal-temperature primary cooling and cryogenic secondary cooling, and the azeotropic acid is obtained at the bottom of the tower. The azeotropic acid is mixed with the boiling breaking agent solution in the high-pressure high-temperature desorption tower, the HCl gas is separated out again by utilizing the principle of breaking the azeotropic point, and the boiling breaking agent solution is treated and recycled.
The concentration of the HCl gas after the analysis is higher and can generally reach more than 99.5 percent. Generally, after the HCl gas is prepared, the HCl gas needs to be dried to obtain a dried HCl gas, thereby facilitating the preparation of chlorosulfonic acid gas.
In the method for preparing chlorosulfonic acid of the present invention, in the HCl gas preparation step, the HCl gas may be dried by using a drying agent, and the drying temperature is 70 ℃ or lower, preferably 55 to 65 ℃; more preferably, the drying agent may be sulfuric acid, the concentration of the sulfuric acid is 93% -100%, and further preferably, the concentration of the sulfuric acid is 97.5% -98.5%.
In the method for producing chlorosulfonic acid of the present invention, the SO3SO-containing gas obtained in the gas preparation step3In the mixed gas of (3), SO38-11% of SO2The content is 0.5-2%, and the balance is air. Prepared to contain SO3The mixed gas does not need to be treated and can be directly used for producing chlorosulfonic acid.
Preferably, the SO3In the gas preparation step, the obtained SO-containing3The temperature of the gas mixture of (a) is between 400 and 500 ℃, preferably between 420 and 480 ℃.
In the present invention, the temperature of the chlorosulfonic acid production step is generally 100 to 180 ℃, preferably 120 to 150 ℃. Preferably, the chlorosulfonic acid preparation step further comprises: and (3) cooling: cooling the chlorosulfonic acid gas to obtain liquid chlorosulfonic acid which is convenient to collect and apply; and (3) a recovery step: reacting unreacted HCl gas with the SO-containing gas3Recovering the unreacted HCl gas and the SO-containing gas3The gas mixture of (a) is mixed again, thereby further producing chlorosulfonic acid gas. In general, the temperature of the recovery step is generally in the range of 30 to 80 ℃ and preferably in the range of 40 to 60 ℃.
<Third embodiment>
A third embodiment of the present invention provides a system for implementing a method for treating off-gas in a chlorosulfonic acid production process according to the first embodiment or in the second embodiment of the present invention, comprising:
an acid wash tower that utilizes an absorbent to absorb SO in the tail gas3A gas;
a water scrubber for absorbing HCl gas in the tail gas with water to obtain hydrochloric acid;
a drying tower that dries SO in the tail gas using a desiccant2A gas.
The system according to the invention, further comprising:
a converter for converting SO in the dried tail gas2Conversion of gas to SO3A gas.
According to the system provided by the invention, the system further comprises one or more of a preheater, a heat exchanger, a heater, an economizer and an absorption tower.
The preheater may be used to preheat the tail gas after the drying step and before the reforming step; the heat exchanger can be used for heat exchange and temperature rise of preheated tail gas, and can also be used for SO-containing gas obtained after conversion3The tail gas is subjected to heat exchange and temperature reduction; the heater (such as an electric furnace) can be used for heating the tail gas after heat exchange and temperature rise SO as to be beneficial to the conversion step, and the coal economizer can be used for reducing the temperature of the converted SO-containing gas3And cooling the tail gas to 150-190 ℃, thereby being beneficial to the implementation of the acid washing step (also called as the absorption step). The absorption tower is used for absorbing SO obtained after the conversion by using an absorbent3SO in the tail gas of (2)3A gas.
According to the system of the present invention, the apparatus for preparing chlorosulfonic acid comprises:
a hydrochloric acid analysis device for analyzing the hydrochloric acid to generate HCl gas;
a sulfuric acid production device, which is used for converting furnace gas generated after burning sulfur into sulfur-containing gas by using a catalystSO3The gas mixture of (a);
a chlorosulfonic acid production unit for reacting the HCl gas with the SO-containing gas3Mixing the gas mixture to obtain chlorosulfonic acid gas.
In the invention, the generated HCl gas can be dried by a drying tower; for SO-containing by preheater and/or heat exchanger3The gas mixture is subjected to heat exchange and temperature reduction, and then the dried HCl gas and the SO subjected to heat exchange and temperature reduction are mixed3Mixing the gases to prepare chlorosulfonic acid gas.
In the invention, the chlorosulfonic acid production device comprises a synthesis tower, a cold separation tower and an auxiliary tower, wherein the synthesis tower is used for mixing the HCl gas and the SO-containing gas3The gas mixture of (a) is mixed to produce chlorosulfonic acid gas. Generally, the temperature of the synthesis column is controlled between 100 and 180 ℃ and preferably between 120 and 150 ℃. The cold separation tower is used for cooling the obtained chlorosulfonic acid gas so as to obtain liquid chlorosulfonic acid; the auxiliary tower is used for mixing the unreacted HCl gas and the SO-containing gas3The recovery of the gas mixture according to (1), generally speaking, the temperature of the auxiliary column is controlled between 30 and 80 ℃ and preferably between 40 and 60 ℃.
As shown in FIG. 1, in practice, in the synthesis column, SO is3Generally in excess, and after recovery in an auxiliary column, the auxiliary column will contain excess SO3May be fed to the auxiliary column, with unreacted HCl gas and SO-containing gas3Is mixed and re-fed to the synthesis column to synthesize chlorosulfonic acid.
Examples
Embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.
Example 1
FIG. 1 shows a process flow diagram for the preparation of chlorosulfonic acid and the treatment of tail gas. As shown in fig. 1, the preparation of chlorosulfonic acid and the tail gas treatment process comprise the following steps:
step 1) in a hydrochloric acid analysis device, analyzing hydrochloric acid to generate HCl gas, then drying the HCl gas by using sulfuric acid with the mass fraction of 98%, and conveying the dried HCl gas to a synthesis tower of a chlorosulfonic acid production device.
Step 2) in a sulfuric acid production device, converting furnace gas generated after burning sulfur to produce SO-containing furnace gas3In which SO is contained3In the gas mixture of (3), SO3The content of SO is 10.5%2The content is 0.8%. Containing SO3The temperature of the gas mixture of (a) is 440-450 ℃. Then using the SO-containing3The gas mixture of (A) is used for preheating the dried tail gas generated in the previous batch for producing chlorosulfonic acid, and the preheated tail gas contains SO3The temperature of the gas mixture is controlled between 160 ℃ and 170 ℃, and then the cooled SO-containing gas mixture is cooled3Is fed to the synthesis tower of a chlorosulfonic acid production plant.
Step 3) drying HCl gas and cooled SO3The gas is synthesized into chlorosulfonic acid gas in a synthesis tower, and the temperature of the synthesis tower is controlled to be 120-130 ℃.
And 4) conveying the chlorosulfonic acid gas synthesized in the step 4) to a cooling tower for cooling to prepare chlorosulfonic acid liquid. And reacting the unreacted HCl gas with the unreacted SO-containing gas3The gas mixture is conveyed to an auxiliary tower for recovery, wherein the temperature of the auxiliary tower is controlled to be 50-60 ℃, and chlorosulfonic acid gas is further prepared.
Step 5) absorbing SO in tail gas generated by chlorosulfonic acid production by circularly spraying 97.8 percent sulfuric acid in an acid cleaning tower3A gas.
And 6) circularly spraying and absorbing HCl gas in the tail gas in a water washing tower by using water, thereby preparing hydrochloric acid with the concentration of 28%.
Step 7) drying the residual tail gas by using 98% sulfuric acid to remove moisture; then using step 3) for preparationThe obtained SO-containing3Preheating the gas mixture, and preheating the dried tail gas to a temperature of between 280 and 290 ℃; then the SO-containing tail gas obtained by the conversion of the last batch of tail gas by the converter is reused3The tail gas is subjected to heat exchange to 380-390 ℃; then heating to 400-410 ℃ by using an electric furnace, then conveying the tail gas heated to 400-410 ℃ to a converter, and carrying out SO treatment on the heated tail gas2Conversion of gas to SO3Gas, SO-containing gas obtained by conversion in a converter3The temperature of the tail gas is 455-465 ℃.
Step 8) conversion by a converter to obtain SO3Utilizing the tail gas of the next batch containing SO3The tail gas preheated by the gas mixture is subjected to heat exchange and temperature reduction to 380-390 ℃, and then is subjected to temperature reduction by an economizer to 160-170 ℃. After the temperature is reduced, 98 percent of sulfuric acid is used for absorption in an absorption tower, wherein the temperature of the absorption tower is controlled to be 55-65 ℃.
Example 2
Step 1) in a hydrochloric acid analysis device, analyzing hydrochloric acid to generate HCl gas, then drying the HCl gas by using sulfuric acid with the mass fraction of 97.5%, and conveying the dried HCl gas to a synthesis tower of a chlorosulfonic acid production device.
Step 2) in a sulfuric acid production device, converting furnace gas generated after burning sulfur to produce SO-containing furnace gas3In which SO is contained3In the gas mixture of (3), SO39.8% of SO2The content is 1.5%. Containing SO3The temperature of the gas mixture of (a) is 420-430 ℃. Then using the SO-containing3The gas mixture of (A) preheats the dried tail gas generated in the previous batch production of chlorosulfonic acid, and the preheated tail gas contains SO3The temperature of the gas mixture is controlled between 170 and 180 ℃, and then the cooled SO-containing gas mixture is cooled3Is fed to the synthesis tower of a chlorosulfonic acid production plant.
Step 3) drying HCl gas and cooled SO3The gas is synthesized into chlorosulfonic acid gas in a synthesis tower, and the temperature of the synthesis tower is controlled to be 100-110 ℃.
Step 4) conveying the synthesized chlorosulfonic acid gas to a cooling deviceCooling in separate tower to obtain chlorosulfonic acid liquid. And reacting unreacted said HCl gas with unreacted said SO-containing gas3The gas mixture is conveyed to an auxiliary tower for recovery, wherein the temperature of the auxiliary tower is controlled to be 40-50 ℃, and chlorosulfonic acid gas is further prepared.
Step 5) absorbing SO in tail gas generated by chlorosulfonic acid production by circularly spraying 97.8 percent sulfuric acid in an acid cleaning tower3A gas.
And 6) circularly spraying and absorbing HCl gas in the tail gas in a water washing tower by using water, thereby preparing hydrochloric acid with the concentration of 28%.
Step 7) drying the residual tail gas by using 97.5 percent sulfuric acid to remove moisture; then utilizing the SO-containing product prepared in the step 3)3Preheating the gas mixture, and preheating the dried tail gas to the temperature of 300-310 ℃; then heating to 400-410 ℃ by using an electric furnace, then conveying the tail gas heated to 400-410 ℃ to a converter, and carrying out SO treatment on the heated tail gas2Conversion of gas to SO3Gas, SO-containing gas obtained by conversion in a converter3The temperature of the tail gas is 455-465 ℃.
Step 8) conversion by a converter to obtain SO3The tail gas is cooled to 180-190 ℃ by an economizer, and is absorbed by 98 percent of sulfuric acid in an absorption tower after being cooled, wherein the temperature of the absorption tower is controlled to be 55-65 ℃.
Comparative example
Step 1) burning SO generated by burning sulfur by using a sulfuric acid production device2Converting furnace gas to produce SO-containing3Then absorbing SO in the gas mixture by sulfuric acid circulation3In sulfuric acid, SO3The concentration is increased to 20 percent, and then a nicotinic acid evaporator is used for evaporation to obtain high-purity SO3Gas, in which SO3The purity of the gas was 99.3%.
And 2) in a hydrochloric acid analysis device, analyzing the hydrochloric acid to generate HCl gas, then drying the HCl gas by using sulfuric acid with the mass fraction of 97.8%, and conveying the dried HCl gas to a synthesis tower of a chlorosulfonic acid production device.
Step 3) mixing the dried HCl gas and the high-purity SO3The gas is synthesized into chlorosulfonic acid gas in a synthesis tower, and the temperature of the synthesis tower is controlled to be 100-110 ℃.
And 4) conveying the chlorosulfonic acid gas synthesized in the step 4) to a cooling tower for cooling to prepare chlorosulfonic acid liquid. And reacting the unreacted HCl gas with SO3The gas is conveyed to an auxiliary tower for recovery, wherein the temperature of the auxiliary tower is controlled to be 40-50 ℃.
Step 5) absorbing SO in tail gas by using 98 percent sulfuric acid in a pickling tower through circulating spraying3A gas.
And 6) circularly spraying and absorbing HCl gas in the tail gas in a water washing tower by using water, thereby preparing hydrochloric acid with the concentration of 28%.
And 7) absorbing the residual tail gas by using alkali liquor and then discharging.
Comparative example 2
Step 1) in a hydrochloric acid analysis device, analyzing hydrochloric acid to generate HCl gas, then drying the HCl gas by using sulfuric acid with the mass fraction of 98.3%, and conveying the dried HCl gas to a synthesis tower of a chlorosulfonic acid production device.
Step 2) in a sulfuric acid production device, converting furnace gas generated after burning sulfur to produce SO-containing furnace gas3In which SO is contained3In the gas mixture of (3), SO3The content of SO is 10.3%2The content was 1.1%. Containing SO3The temperature of the gas mixture of (a) is 450-460 ℃. Then using the SO-containing3The gas mixture exchanges heat with the dried tail gas generated in the previous batch of chlorosulfonic acid production, and the preheated tail gas contains SO3The temperature of the gas mixture is reduced to 150-160 ℃, and then the cooled SO-containing gas mixture is cooled3Is fed to the synthesis tower of a chlorosulfonic acid production plant.
Step 3) drying HCl gas and cooled SO3The gas is synthesized into chlorosulfonic acid gas in a synthesis tower, and the temperature of the synthesis tower is controlled to be 120-130 ℃.
Conveying the chlorosulfonic acid gas synthesized in the step 4) to a cooling tower for cooling to prepare chlorosulfonic acidAnd (3) acid liquid. And reacting unreacted said HCl gas with said SO3The gas mixture of (a) is sent to an auxiliary tower for recovery, wherein the temperature of the auxiliary tower is controlled to be 50-60 ℃.
And 5) absorbing tail gas generated in the chlorosulfonic acid production by using alkali liquor and then discharging.
Effect testing
The contents of chlorosulfonic acid prepared in examples 1 to 2 and comparative examples 1 to 2 were measured, and the heat energy recycling and the effect of tail gas treatment were evaluated as shown in table 1 below.
TABLE 1
Wherein, the testing method of the chlorosulfonic acid content utilizes a chemical titration method in 4.3.2 in GB/T13549-2016 to detect.
As can be seen from the results of the tests of examples 1-2 and comparative examples 1-2, the chlorosulfonic acid content produced by the method and apparatus of the present application meets the requirements of first-class chlorosulfonic acid. The hydrochloric acid and the sulfuric acid prepared by the tail gas treatment method can be directly reused in the chlorosulfonic acid production procedure, so that the waste of resources is avoided.
Compared with the comparative examples 1-2, the heat energy and the tail gas of the embodiment of the invention can be comprehensively utilized, the absorption discharge liquid is not generated, the process operation is simple, and the obtained SO3The tail gas of the invention can be directly used in the production process of chlorosulfonic acid, does not need to be absorbed and discharged by alkali liquor, and can be comprehensively utilized to produce hydrochloric acid and sulfuric acid.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and the present invention shall be covered thereby. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (23)
1. A tail gas treatment method in a chlorosulfonic acid preparation process is characterized by comprising the following steps:
acid washing step: absorbing SO in the tail gas by using an absorbent3A gas;
and (3) water washing: absorbing HCl gas in the tail gas by using water to obtain hydrochloric acid;
and (3) drying: drying the SO in the tail gas by using a drying agent2A gas;
preheating: by using SO obtained in the preparation of chlorosulfonic acid3The dried tail gas is preheated by the gas mixture; wherein said SO is contained3The temperature of the gas mixture of (a) is between 400 and 500 ℃; after preheating, contains SO3The temperature of the gas mixture of (a) is between 150 and 200 ℃; the temperature of the preheated tail gas is between 250 and 350 ℃;
a heat exchange step: carrying out heat exchange treatment on the preheated tail gas, and carrying out heat exchange on the preheated tail gas to 340-430 ℃;
a heating step: heating the heat-exchanged tail gas to 380-450 ℃ by a heater;
a conversion step: SO in the heated tail gas is treated under the action of a catalyst2Conversion of gas to SO3Gas to obtain SO-containing gas3Using said SO-containing tail gas3The tail gas exchanges heat with the preheated tail gas of the next batch.
2. The method for treating tail gas generated in the process of preparing chlorosulfonic acid according to claim 1, wherein the concentration of hydrochloric acid obtained in the water washing step is 28 to 34%.
3. The method for treating tail gas generated in the process of preparing chlorosulfonic acid according to claim 2, wherein the concentration of hydrochloric acid obtained in the water washing step is 28 to 32%.
4. The method for treating off-gas from chlorosulfonic acid production according to any of claims 1 to 3, wherein the temperature of the acid washing step is 70 ℃ or lower; the absorbent comprises sulfuric acid.
5. The method for treating tail gas generated in the preparation process of chlorosulfonic acid of claim 4, wherein the concentration of sulfuric acid is 93% to 100%.
6. The method for treating tail gas generated in the preparation process of chlorosulfonic acid according to claim 5, wherein the concentration of sulfuric acid is 97.5 to 98.5 percent.
7. The method for treating off-gas from a chlorosulfonic acid production process of any of claims 1 to 3, wherein the temperature of the drying step is 70 ℃ or lower; the desiccant comprises sulfuric acid.
8. The method for treating tail gas generated in the process of preparing chlorosulfonic acid according to claim 7, wherein the concentration of sulfuric acid is 93 to 100%.
9. The method of claim 8, wherein the concentration of sulfuric acid is 97.5-98.5%.
10. The method for treating off-gas from chlorosulfonic acid production as claimed in any of claims 1 to 3, wherein the temperature of the converting step is controlled to be between 380 ℃ and 450 ℃.
11. The method for treating tail gas from chlorosulfonic acid production process of claim 10, wherein the temperature of said converting step is controlled to be between 400-420 ℃.
12. The method for treating tail gas from chlorosulfonic acid production process of any of claims 1 to 3, wherein said SO comprises3The temperature of the gas mixture of (a) is between 420 and 480 ℃.
13. The method for treating tail gas from chlorosulfonic acid production of any of claims 1 to 3, wherein the temperature of the heat exchanged tail gas is between 340 and 430 ℃.
14. The method for treating tail gas generated in the preparation process of chlorosulfonic acid of claim 13, wherein the temperature of the tail gas after heat exchange is 370-400 ℃.
15. The preparation method of chlorosulfonic acid is characterized by comprising the following steps:
HCl gas preparation step: resolving hydrochloric acid to generate HCl gas;
SO3a gas preparation step: the SO-containing gas generated after burning the sulfur is converted and produced by a catalyst3The gas mixture of (a);
chlorosulfonic acid preparation step: reacting said HCl gas with said SO3Mixing the gas mixture to obtain chlorosulfonic acid gas;
and (3) tail gas treatment: the exhaust gas treatment process according to any one of claims 1 to 14.
16. The method of claim 15, wherein the step of preparing chlorosulfonic acid further comprises:
and (3) cooling: cooling the chlorosulfonic acid gas;
and (3) a recovery step: reacting unreacted HCl gas with the SO-containing gas3Recovering the gas mixture of (1).
17. A method for the preparation of chlorosulfonic acid of claim 15 or 16 wherein said SO is3SO-containing gas obtained in the gas preparation step3In the gas mixture of (3), SO38-11% of SO2The content is 0.5-2%.
18. The method of claim 17, wherein the SO comprises3The temperature of the gas mixture of (a) is between 400 and 500 ℃.
19. The method of producing chlorosulfonic acid of claim 18 wherein said SO comprises3The temperature of the gas mixture of (a) is between 420 and 480 ℃.
20. A system for carrying out the method for treating off-gas from chlorosulfonic acid production of any of claims 1 to 14 comprising:
an acid wash tower that utilizes an absorbent to absorb SO in the tail gas3A gas;
a water scrubber for absorbing HCl gas in the tail gas with water to obtain hydrochloric acid;
a drying tower that dries SO in the tail gas using a desiccant2A gas;
preheater using SO-containing gas obtained in the production of chlorosulfonic acid3The dried tail gas is preheated by the gas mixture of (a), wherein the SO is contained3The temperature of the gas mixture of (a) is between 400 and 500 ℃; after preheating, contains SO3The temperature of the gas mixture of (a) is between 150 and 200 ℃; the temperature of the preheated tail gas is between 250 and 350 ℃;
a heat exchanger: the heat exchanger is used for carrying out heat exchange treatment on the preheated tail gas, and carrying out heat exchange on the preheated tail gas to 340-430 ℃;
a heater: the device is used for heating the tail gas subjected to heat exchange to 380-450 ℃;
a converter for converting SO in the preheated tail gas2Conversion of gas to SO3Gas using said SO-containing gas3The tail gas exchanges heat with the preheated tail gas of the next batch.
21. The system of claim 20, further comprising: one or a combination of two of the economizer and the absorption tower.
22. The system of claim 20 or 21, wherein the equipment for preparing the chlorosulfonic acid comprises:
a hydrochloric acid analysis device for analyzing the hydrochloric acid to generate HCl gas;
a sulfuric acid production device, which is used for converting furnace gas generated after burning sulfur into SO-containing gas by using a catalyst3The gas mixture of (a);
a chlorosulfonic acid production unit for reacting the HCl gas with the SO-containing gas3Mixing the gas mixture to obtain chlorosulfonic acid gas.
23. The system of claim 22, wherein the chlorosulfonic acid production means comprises: a synthesis column, a cold separation column and an auxiliary column, wherein
The synthesis tower is used for mixing the HCl gas and the SO-containing gas3Mixing the gas mixture to obtain chlorosulfonic acid gas;
the cold separation tower is used for cooling the obtained chlorosulfonic acid gas;
the auxiliary tower is used for mixing the unreacted HCl gas and the SO-containing gas3Recovering the gas mixture of (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810632199.8A CN108557775B (en) | 2018-06-19 | 2018-06-19 | Tail gas treatment method in chlorosulfonic acid preparation process, system for implementing method and chlorosulfonic acid preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810632199.8A CN108557775B (en) | 2018-06-19 | 2018-06-19 | Tail gas treatment method in chlorosulfonic acid preparation process, system for implementing method and chlorosulfonic acid preparation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108557775A CN108557775A (en) | 2018-09-21 |
| CN108557775B true CN108557775B (en) | 2020-06-02 |
Family
ID=63553845
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810632199.8A Active CN108557775B (en) | 2018-06-19 | 2018-06-19 | Tail gas treatment method in chlorosulfonic acid preparation process, system for implementing method and chlorosulfonic acid preparation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108557775B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109668131B (en) * | 2018-12-10 | 2020-01-17 | 山东京博众诚清洁能源有限公司 | System and process for preparing medium-pressure steam by utilizing waste heat in sulfuric acid production |
| CN111320141A (en) * | 2020-03-05 | 2020-06-23 | 浙江巨化股份有限公司硫酸厂 | Production process for synthesizing high-purity chlorosulfonic acid by gas phase circulation method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1164479C (en) * | 2002-11-13 | 2004-09-01 | 顾林建 | Technology of synthesizing high concentration chlorosulfonic acid using low concentration salfur trioxide |
| KR101796236B1 (en) * | 2015-11-27 | 2017-11-09 | 주식회사 포스코 | Method for remonal of carbon dioxide from flue gas and device for the same |
| CN107983090A (en) * | 2017-11-30 | 2018-05-04 | 山东凯盛新材料股份有限公司 | The technique of the acyl chlorides tail gas comprehensive regulation |
-
2018
- 2018-06-19 CN CN201810632199.8A patent/CN108557775B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN108557775A (en) | 2018-09-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108557775B (en) | Tail gas treatment method in chlorosulfonic acid preparation process, system for implementing method and chlorosulfonic acid preparation method | |
| US4053507A (en) | Method of recovering unreacted materials and heat in urea synthesis | |
| SU1421254A3 (en) | Method of producing hydrogen fluoride | |
| CN103896215A (en) | Fluorite-sulfuric acid method for preparing hydrogen fluoride | |
| TW201136872A (en) | Method to recover organic tertiary amines from waste sulfuric acid | |
| CN105645358A (en) | Method for preparing hydrogen fluoride from fluosilicic acid | |
| CN110203898A (en) | A kind of mixed acid waste liquor recovery method | |
| CN110817912A (en) | Process for directly treating and utilizing hydrogen chloride gas | |
| US3490868A (en) | Method of recovery of sulphuric acid | |
| TW201136871A (en) | Method to recover organic tertiary amines from waste sulfuric acid employing a plug flow reactor | |
| US20100143236A1 (en) | Preparation of hydrogen fluoride from calcium fluoride and sulfuric acid | |
| US2405747A (en) | Recovery of acidic gases | |
| JPS5943402B2 (en) | Method for producing sulfuric acid | |
| US2879135A (en) | Manufacture of sulfuric acid | |
| CN104774162B (en) | Method used for preparing diethyl sulfate | |
| US3285695A (en) | Production of ammonium nitrate | |
| US3449079A (en) | Hydrogen halide oxidation in acid medium | |
| CN109651072B (en) | Method for preparing chloroethane from hydrochloric acid containing sulfur dioxide | |
| US1901416A (en) | Production of gaseous mixtures containing sulphur dioxide | |
| CN105645363A (en) | Sulfuric acid producing method capable of drying gas twice and increasing waste heat recovery rate | |
| CN108862208A (en) | A kind of processing method of the Waste Sulfuric Acid of alkylation production process discharge | |
| US2123072A (en) | Process for the treatment of gases | |
| US1930664A (en) | Process for the recovery of free chlorine from chlorides | |
| CN109052332B (en) | Method for preparing chlorosulfonic acid by regenerating high-COD (chemical oxygen demand) saline dilute acid | |
| CN108328583B (en) | A kind of production technology of refined sulfuric acid reagent |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |