Electronic grade high-purity hydrogen chloride preparation system
Technical Field
The utility model relates to a purification field, concretely relates to high-purity hydrogen chloride preparation system of electron level.
Background
The prior art mainly adopts the following methods for producing hydrogen chloride:
the method comprises the following steps: a synthesis method;
3.1.1, basic principle: hydrogen and chlorine gas are combusted to generate hydrogen chloride H2+CL2→2HCL
3.1.2, description of disadvantages and drawbacks:
(1) the ignition difficulty is high;
(2) once flameout occurs in the combustion process, the ignition is troublesome again, the explosion risk exists, and the potential safety hazard is large;
(3) huge heat energy is brought in the combustion process, water cooling is utilized, once the reaction kettle is punctured, huge acidic liquid hydrochloric acid is formed, the treatment difficulty is high, drugs are easy to prepare, the management is not good, and the social hazard is huge;
3.2, a second method for producing hydrogen chloride in the prior art: an analytical method: dewatering by concentrated hydrochloric acid
3.2.1, basic principle: HCL. H2O+H2SO4(concentrated) → HCL (anhydrous) + H2SO4·H2O
3.2.2, description of disadvantages and drawbacks:
(1) the corrosion of concentrated hydrochloric acid and hot concentrated sulfuric acid is severe, the requirement on equipment is severe, and the manufacturing cost of the equipment is high;
(2) a large amount of waste acid (mixture of hydrochloric acid and sulfuric acid) is generated in the production process, and the environmental protection pressure is huge;
(3) a large amount of heat is generated in the production process, so that violent boiling and high-temperature liquid splashing are easily caused, and the safety is not high;
(4) concentrated hydrochloric acid and concentrated sulfuric acid are easy to prepare poison management substances, and the administrative procedures of purchasing and transporting are troublesome;
3.3, a third method for producing hydrogen chloride in the prior art: double decomposition method
3.3.1, basic principle: concentrated sulfuric acid reacts with roasted potassium chloride (sodium chloride)
KCL(NaCL)+H2SO4(concentrated) → HCL (anhydrous) + KHSO4(NaHSO4)
3.3.2, description of disadvantages and drawbacks:
(1) the alkali metal hydrochloride is easy to harden and agglomerate in the roasting process, so that the reaction cannot be completely finished, the consumption of materials is serious, more solid wastes are generated, and the environmental protection pressure is huge;
(2) other weak acid salt species are present in alkali metal hydrochlorides and other acidic species are present during metathesis reactions, such as: hydrogen sulfide, hydrogen bromide, carbon dioxide and the like, and the impurities are more, the subsequent purification treatment difficulty is high, and the product quality stability is poor;
(3) the double decomposition reaction has high temperature, strict requirements on materials of a reaction kettle, high energy consumption and unobvious economic value advantages.
Disclosure of Invention
The utility model aims at providing a higher and more environmental protection's of security electron level high-purity hydrogen chloride preparation system.
In order to achieve the above purpose, the utility model adopts the technical scheme that: an electronic grade high purity hydrogen chloride production system comprising:
a feed gas source for providing a feed gas comprising hydrogen chloride;
a first gas compression delivery apparatus for compressed delivery of a feed gas, an inlet of the first gas compression delivery apparatus being in communication with the feed gas source;
the dryer is used for removing moisture in the raw material gas, and the inlet of the dryer is communicated with the outlet of the first gas compression conveying device;
the second gas compression conveying device is used for conveying the feed gas in a compression mode, and an inlet of the second gas compression conveying device is communicated with an outlet of the dryer;
a gas phase inlet of the pre-cooling liquefier is communicated with an outlet of the second gas compression conveying equipment
The light component removal rectifying tower is used for removing light components in the feed liquid and obtaining a tower bottom product A, and a feed liquid inlet in the middle of the light component removal rectifying tower is communicated with a liquid phase outlet of the pre-cooling liquefier;
the heavy component removal rectifying tower is used for removing heavy components of a tower bottom product A and obtaining reflux liquid and a tower bottom product B, and a middle feed liquid inlet of the heavy component removal rectifying tower is communicated with a tower bottom product outlet of the light component removal rectifying tower;
the finished product tank is used for storing finished product hydrogen chloride, and an inlet of the finished product tank is communicated with a reflux liquid pipeline of the de-heavy rectifying tower;
and the recovery rectifying tower is used for vaporizing liquid hydrogen chloride in the tower bottom product B, a middle feed liquid inlet of the recovery rectifying tower is communicated with a tower bottom product outlet of the de-heavy rectifying tower, and a tower top product outlet of the recovery rectifying tower is communicated with an inlet of the first gas compression conveying equipment or an inlet of the second gas compression conveying equipment.
Preferably, the raw material gas source is a raw material gas storage tank or a production line for producing monochlorotoluene by chlorination reaction of toluene and chlorine, and an inlet of the first gas compression conveying equipment is communicated with an outlet of the raw material gas storage tank, or an inlet of the first gas compression conveying equipment is communicated with a byproduct hydrogen chloride gas outlet of the production line.
Preferably, the first gas compression conveying device is a screw compressor.
Preferably, the second gas compression delivery device is a diaphragm compressor.
Preferably, the dryer is provided with a molecular sieve.
Preferably, the top product outlet of the light component removal rectifying tower is communicated with a light component recovery system.
Preferably, the bottom product outlet of the recovery rectifying tower is communicated with a heavy component recovery system.
Because of the application of the technical scheme, compared with the prior art, the utility model has the following advantages:
the utility model discloses an electronic grade high-purity hydrogen chloride preparation system, which changes the process of converting hydrogen chloride generated after the original toluene chlorination process into hydrochloric acid into a production method for producing electronic grade high-purity hydrogen chloride, and industrial hydrochloric acid is basically rich in waste liquid in the practical chemical production and needs to be treated; the electronic grade high-purity hydrogen chloride has wide application, so the utility model changes waste into valuable, does not cause new pollution, lightens the environmental protection pressure, improves the economic benefit, and improves the safety and does not cause explosion danger compared with a synthesis method; compared with a dehydration method, the safety is improved, the environmental protection pressure is greatly reduced, the equipment construction requirement is reduced, and the administrative risk is reduced; compared with a double decomposition method, the method has the advantages that the safety and the environmental protection pressure are improved, the subsequent treatment difficulty is reduced, the purification of products and the yield are improved, the competitiveness is improved, and the precooling liquefier is arranged, so that the cold load of the light component removal rectifying tower is reduced, and the running stability (especially the operating pressure) of the device is improved.
Drawings
Fig. 1 is a schematic connection diagram of an electronic grade high purity hydrogen chloride production system disclosed in the present invention.
Wherein: 1. a source of raw gas; 2. a first gas compression delivery device; 3. a dryer; 4. a second gas compression delivery device; 5. a light component removal rectifying tower; 6. a heavy component removal rectifying tower; 7. a finished product tank; 8. recovering the rectifying tower; 9. a pre-cooling liquefier; 10. a vaporizer; 11. a steel cylinder.
Detailed Description
The invention will be further described with reference to the accompanying drawings and examples:
referring to fig. 1, an electronic grade high purity hydrogen chloride production system, as shown in the figure, comprises:
a feed gas source 1 for providing a feed gas comprising hydrogen chloride;
the first gas compression conveying device 2 is used for conveying the raw material gas in a compression mode, and an inlet of the first gas compression conveying device 2 is communicated with the raw material gas source 1;
the dryer 3 is used for removing moisture in the feed gas, and an inlet of the dryer 3 is communicated with an outlet of the first gas compression conveying device 2;
the second gas compression conveying device 4 is used for conveying the raw material gas in a compression mode, and an inlet of the second gas compression conveying device 4 is communicated with an outlet of the dryer 3;
a light component removing rectifying tower 5 for removing light components in the feed liquid and obtaining a tower bottom product A, wherein a feed liquid inlet in the middle of the light component removing rectifying tower 5 is communicated with an outlet of the second gas compression conveying equipment 4;
the heavy component removal rectifying tower 6 is used for removing the heavy components of the tower bottom product A and obtaining reflux liquid and a tower bottom product B, and a middle feed liquid inlet of the heavy component removal rectifying tower 6 is communicated with a tower bottom product outlet of the light component removal rectifying tower 5;
the finished product tank 7 is used for storing finished product hydrogen chloride, and an inlet of the finished product tank is communicated with a reflux liquid pipeline of the heavy component removal rectifying tower;
a recovered hydrogen chloride rectifying tower 8 for vaporizing liquid hydrogen chloride in the tower bottom product B, wherein a middle feed liquid inlet of the recovered hydrogen chloride rectifying tower 7 is communicated with a tower bottom product outlet of the heavy component removing rectifying tower 6;
and the precooling liquefier 9 is used for liquefying the gaseous hydrogen chloride, a gas phase inlet of the precooling liquefier 9 is communicated with an outlet of the second gas compression conveying equipment 4, and a middle feed liquid inlet of the light component removal rectifying tower 5 is communicated with a liquid phase outlet of the precooling liquefier 9.
The process of converting hydrogen chloride generated after the original toluene chlorination process into hydrochloric acid is changed into a production method for producing electronic-grade high-purity hydrogen chloride, and industrial hydrochloric acid is basically rich in waste liquid in the practical chemical production and needs to be treated; therefore, the invention changes waste into valuable, does not cause new pollution, lightens the pressure of environmental protection, improves the economic benefit, and has improved safety and no explosion hazard compared with a synthesis method; compared with a dehydration method, the safety is improved, the environmental protection pressure is greatly reduced, the equipment construction requirement is reduced, and the administrative risk is reduced; compared with a double decomposition method, the method has the advantages that the safety and the environmental protection pressure are improved, the subsequent treatment difficulty is reduced, the purification of products and the yield are improved, the competitiveness is improved, and the precooling liquefier is arranged, so that the cold load of the light component removal rectifying tower is reduced, and the running stability (especially the operating pressure) of the device is improved.
In the preferred embodiment of the present embodiment, the top product outlet of the hydrogen chloride recovery rectifying tower 7 is communicated with the inlet of the second gas compression conveying device 4.
In a preferred embodiment of the present embodiment, the raw material gas source 1 is a production line for producing monochlorotoluene by chlorination reaction of toluene and chlorine, and the inlet of the first gas compression conveying device 1 is communicated with the byproduct hydrogen chloride gas outlet of the production line.
In a preferred embodiment of this embodiment, the first gas compression conveying device 2 is a screw compressor.
In the preferred embodiment of this embodiment, the second gas compressing and delivering device 4 is a diaphragm compressor.
In a preferred embodiment of this example, the dryer 3 is provided with a molecular sieve.
In the preferred embodiment of this example, the overhead product outlet of the light ends removal rectification column 5 is connected to a light ends recovery system (not shown).
In the preferred embodiment of the present embodiment, the bottom product outlet of the rectification column 6 for recovering hydrogen chloride is communicated with a heavy component recovery system (not shown in the figure).
The preferred embodiment in this embodiment further includes:
the pressure boosting vaporizer 10 is used for boosting the pressure of the liquid hydrogen chloride in the finished product tank 8, and an inlet and an outlet of the pressure boosting vaporizer 10 are communicated with the finished product tank 8;
and the steel cylinder 11 is used for storing the product hydrogen chloride, and an inlet of the steel cylinder 11 is communicated with an outlet of the finished product tank 8.
Through set up the vaporizer that steps up at the finished product jar, the hydrogen chloride in to the finished product jar steps up, does not need to adopt mechanical pump during filling dress, also need not the vacuum pump moving part for the power consumption reduces, the system is simple, be difficult for leaking, can not cause secondary pollution.
Carrying out chlorination reaction on toluene and chlorine to produce chlorotoluene and byproduct hydrogen chloride gas, wherein the byproduct is used as a raw material and is compressed to be not less than 5bar by a screw compressor; removing water content to be below 20PPm through molecular sieve adsorption, compressing the water content to 10-80 bar through a diaphragm compressor, entering a precooling liquefier which takes liquid nitrogen (without extra compression and pressurization), dichloromethane, glycol and water mixed liquid or cooling water as a refrigerant, exchanging heat through a condenser at-70-50 ℃, and condensing gaseous hydrogen chloride into liquid hydrogen chloride; feeding liquid hydrogen chloride from an inlet at the middle lower part of the light component removal rectifying tower, and removing substances (such as hydrogen, nitrogen, oxygen, carbon monoxide, methane and the like) with lower boiling points than the hydrogen chloride through the light component removal rectifying tower; the operating pressure of the light component removal rectifying tower is as follows: 5-80 bar; when the light components in the light component removal rectifying tower meet the design requirements, discharging from the bottom of the light component removal rectifying tower, entering the lower part of the heavy component removal rectifying tower, removing substances (such as moisture, chlorine, chlorotoluene, toluene, metal ions and the like) with a boiling point higher than that of hydrogen chloride by the heavy component removal rectifying tower, and operating pressure of the heavy component removal rectifying tower: 5-80 bar (slightly lower than the working pressure of the light component removal rectifying tower); when the heavy component meets the standard of electronic grade high-purity hydrogen chloride, separating and collecting liquid hydrogen chloride from the reflux liquid at the top of the de-heavy rectifying tower in a product intermediate tank or a finished product tank as an electronic grade product for later use; the light components separated from the top of the light component removal rectifying tower are absorbed by a tail gas absorption system to be byproduct industrial hydrochloric acid, and the heavy components separated from the bottom of the heavy component removal rectifying tower contain liquid chlorine which is absorbed by the tail gas absorption system to be byproduct industrial sodium hypochlorite and industrial hydrochloric acid byproduct. The whole process changes the process of converting hydrogen chloride generated after the original toluene chlorination process into hydrochloric acid into a production method for producing electronic-grade high-purity hydrogen chloride, and industrial hydrochloric acid is basically rich in waste liquid in the actual chemical production and needs to be treated; therefore, the invention changes waste into valuable and does not cause new pollution.
The indexes of a crude product are as follows after the mixture generated by the chlorination reaction of industrial chlorine and toluene is subjected to preliminary freezing separation and simple rectification:
name (R)
|
HCL
|
CL2 |
H2 |
O2+Ar
|
N2 |
CO
|
CO2
|
CH4 |
H2O
|
CH3-PH-CL
|
Concentration of
|
97.6%
|
2%
|
0.3%
|
20ppm
|
800ppm
|
20ppm
|
1ppm
|
5ppm
|
200ppm
|
5ppm |
After the crude hydrogen chloride is pressurized to 5bar by a compressor, the water is removed by a molecular sieve adsorbent to below 20PPm, and the crude hydrogen chloride directly enters a precooler, wherein the precooler adopts case one, case two and case three as refrigerants, and the specific operating temperature is shown in the following table:
example one:
the precooling liquefier takes liquid nitrogen as a refrigerant, and the light component removing rectifying tower and the heavy component removing rectifying tower adopt a low-temperature low-pressure rectifying mode
Example two:
the precooling liquefier takes dichloromethane and glycol as refrigerants, and the light component removing rectifying tower and the heavy component removing rectifying tower adopt a low-temperature medium-pressure rectifying mode
Example three:
the precooling liquefier adopts a cooling water medium, and the light component removing rectifying tower and the heavy component removing rectifying tower adopt a normal-temperature high-pressure rectifying mode
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.