CN102161474A - Method for refining hydrogen chloride gas - Google Patents
Method for refining hydrogen chloride gas Download PDFInfo
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- CN102161474A CN102161474A CN2010102747618A CN201010274761A CN102161474A CN 102161474 A CN102161474 A CN 102161474A CN 2010102747618 A CN2010102747618 A CN 2010102747618A CN 201010274761 A CN201010274761 A CN 201010274761A CN 102161474 A CN102161474 A CN 102161474A
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- hydrogen
- chloride gas
- hydrogen chloride
- oxygen
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Abstract
The invention provides a method for refining a hydrogen chloride gas and aims to provide a refining method with simple process flow, high hydrogen-removing rate and capacities of reducing refining procedures and saving energy cost. The method comprises the following steps of: measuring hydrogen content of the hydrogen chloride gas by using a hydrogen on-line monitoring instrument; under the condition that the hydrogen content does not exceed 14 percent (v/v), measuring the volume of the hydrogen-containing hydrogen chloride gas and the volume of oxygen/air respectively by using a flowmeter; adding a small amount of excess oxygen into the reaction, so that the molar ratio of the hydrogen to the oxygen is controlled to be 2:1-1.2, wherein the hydrogen and the oxygen enter the pipeline and are mixed uniformly; performing combustion reaction on the hydrogen and the oxygen in the reaction region in a combustor to generate water vapor and remove the hydrogen; and drying the purified hydrogen chloride gas and entering the next step, namely the high-temperature chlorinated alkane production procedure. The hydrogen content of the processed hydrogen chloride gas can be reduced to below 0.16 percent (v/v). The problems of subsequent treatment of a large amount of diluted hydrochloric acid and environmental pollution are solved.
Description
Technical field
The present invention relates to a kind of process for purification of hydrogen chloride gas.
Background technology
Be raw material with chlorine and hydrogen, adopting combustion method to prepare in the hydrogen chloride gas production technique, for making the chlorine energy perfect combustion with hypertoxic gas, regular meeting uses slightly excessive hydrogen.The hydrogen that so just often contains 6~14% (v/v) in the hydrogen chloride gas of feasible preparation.And be in the production chloralkane technology of raw material with hydrogen chloride gas and methyl alcohol, hydrogen in the hydrogen chloride gas is insoluble to methanol solution and is not participate in reacting, hydrogen can be assembled on reactor top, and when reaching its limits of explosion scope, concentration very easily blasts, bring serious potential safety hazard for the production of chloralkane, therefore, all must make with extra care usually, to remove hydrogen to the hydrogen chloride gas that contains hydrogen.And burning hydrogen must be resolved firing of hydrogen.
In having the production technique of removing hydrogen in the hydrogen chloride gas now, all be to contain the hydrogen chloride gas of hydrogen by film-falling absorption tower and water reaction, obtain 31% concentrated hydrochloric acid, hydrogen then carries out emptying by emptying device, through desorption tower used concentrated hydrochloric acid is heated to 142 ℃ again, hydrogen chloride gas is separated out make pure hydrogen chloride gas.Mainly there are following two problems in this technology: 1,, need to consume a large amount of steam heatings when adding the heat evolution hydrogen chloride gas desorption tower used, caused the waste of the too high and resource of production energy cost.2, produce 7 tons 18.5% dilute hydrochloric acid with 1 ton of hydrogen chloride gas of this prepared.And the dilute hydrochloric acid industrial utilization that produces value is not high, and present domestic dilute hydrochloric acid production capacity is also serious superfluous, and is therefore, relatively difficult as commodity selling.Chlorion has severe corrosive to hardware in the dilute hydrochloric acid, is not easy to store.Dilute hydrochloric acid must just can be discharged in the outside atmosphere through environmental protection treatment, and this has just increased the environmental protection cost, and the environmental protection treatment technology also is a bottleneck of modern industrial technology simultaneously.
As in the process route view of the disclosed a kind of refining hydrogen chloride gas of JT54097597 Japanese patent application case shown in Figure 3, this method mainly is by a cover series-parallel connection bonded burner 1, combustion tower 2, water cooler 3, absorption tower 4, recovery tower 5, hydrogen is sent into mouth 6, chlorine is sent into mouth 7, and rough hydrogen chloride gas is sent into mouth 8, and hydrochloride aqueous solution is extracted mouth 9 out, gas discharge outlet 10, water-in 11, water send into mouthfuls 12, and oxygen is sent into mouthfuls 13 and burnt and remove organic substance in the hydrogen chloride gas.The purified hydrogen chloride gas is prepared into hydrochloric acid after water absorbs.Its production technique is that the hydrogen chloride gas with hydrogen absorbs by water, and water-fast hydrogen is got rid of in emptying, obtains 31% saturated hydrochloric acid, again its saturated hydrochloric acid is heated to 142 ℃, and pure hydrogen chloride gas and remaining 18.5% dilute hydrochloric acid are separated out in evaporation.This method weak point is, it is wayward to remove in the hydrogen technology hydrogen/oxygen ratio, easily brings hidden danger and hydrogen a difficult problem such as can not remove fully.Will be when adding the heat evolution hydrogen chloride gas, need to consume a large amount of steam heatings, caused the waste of the too high and resource of production energy cost, by product dilute hydrochloric acid amount is big, can cause severe contamination to environment.
Summary of the invention
The objective of the invention is provides a kind of technical process simple, easy to operate at above-mentioned the deficiencies in the prior art part, processing power is big, and hydrogen is removed the efficient height, but the refining hydrogen chloride gas of serialization, and do not have potential safety hazard, can reduce refining step, the process for purification of save energy cost.
Above-mentioned purpose of the present invention can realize by following measure, a kind of process for purification of hydrogen chloride gas, has following technical characterictic: before purification of chlorinated hydrogen, at first hydrogen content in the hydrogen chloride gas is measured with hydrogen on-line monitoring instrument, be no more than at hydrogen content under the situation of 14% (v/v), measure the hydrogen chloride gas that contains hydrogen and the volume of oxygen/air respectively by under meter, enter hydrogen and oxygen mol ratio content in the pipeline by the control of the under meter on the pipeline, in reaction, add a small amount of excess of oxygen, make to enter and carry out well-mixed hydrogen in the pipeline and the oxygen mol ratio is controlled at 2: 1~1.2 scopes, mixed gas enters first step flame damper, and by behind the flame damper of the second stage, enter the first-stage burning device, hydrogen chloride gas and air/oxygen gaseous reaction mixture are at first-stage burning device conversion zone, allow hydrogen and the oxygen conversion zone in burner carry out combustion reactions and generate water vapor, remove hydrogen; At last the hydrogen chloride gas behind the purifying is carried out drying treatment, enter next step high-temp chlorination alkane production process.
The present invention has following beneficial effect than prior art.
The present invention at first carries out the mensuration that hydrogen content in the hydrogen chloride gas is no more than 14% (v/v), has guaranteed the normal operation of reaction system.Contain the hydrogen chloride gas of hydrogen and air/oxygen through the accurate proportioning of under meter, guaranteed that flameholding carries out and do not blast.Allow the hydrogen chloride gas and the oxygen that contain hydrogen carry out combustion reactions in burner, hydrogen safety and stability burning in burner realizes the purpose of refining hydrogen chloride gas, thereby makes it can directly enter next step production process safely.
When making with extra care hydrogen chloride gas, at the conversion zone of refining hydrogen chloride gas, the oxygen of adding slightly is in excess in hydrogen, makes combustion of hydrogen more complete, has guaranteed that the removal of hydrogen is complete, to satisfy the requirement of subsequent processing to hydrogen chloride gas purity.
Adopt the refining hydrogen chloride gas of combustion method, reaction product is a water vapor, makes hydrogen remove the pollution that does not cause by product in the process.After hydrogen chloride gas carried out drying treatment, the purification of chlorinated hydrogen that obtains can directly carry out subsequent processing and react, and then eliminated the potential safety hazard that may produce blast, simultaneously guaranteed that also the purity of hydrogen chloride gas has reduced production process again, save energy cost, reduced the generation of superfluous dilute hydrochloric acid.And whole technological process is simple, and is safe, easy to operate, is easy to realize suitability for industrialized production.
At conversion zone, provide the proportioning of (hydrogen: oxygen is 2: 1.0~1.2) to the system starting material, can realize the stably refining hydrogen chloride gas of continuous long period.The present invention reaches different purity requirements according to the requirement of hydrogen content in the hydrogen chloride gas by one-level, secondary or multistage combustion.
Experimental results show that, the present invention adopts the multistage combustion method to make with extra care hydrogen chloride gas, compares with the existing hydrogen technology of removing, and 1 ton of hydrogen chloride gas of every purifying can be saved 5~6 tons of steams, the facility investment of an operation be can save, and the subsequent disposal and the problem of environmental pollution of a large amount of dilute hydrochloric acid solved.Through the hydrogen chloride gas that the present invention handles, its hydrogen content can be reduced to below 0.16% (v/v).
Description of drawings
Fig. 1 is the process flow sheet of hydrogen chloride gas process for purification of the present invention.
Fig. 2 is the structure perspective diagram of burner of the present invention.
Fig. 3 is the process route view of the refining hydrogen chloride gas of prior art.
Among the figure: 1-burner ingress pipe, 2. nichrome wire, 3. electrically heated storehouse, 4. water outlet, 5. combustion chamber cylindrical shell, 6. burner delivery line, 7. cooling room, 8. water-in, 9. insulation jacket.
Embodiment
Consult Fig. 1.Present method is with the refining hydrogen chloride gas of the mode burning hydrogen of resistance wire, allow hydrogen and oxygen carry out the smooth combustion reaction, conversion zone at the preparation hydrogen chloride gas, importing contains the hydrogen chloride gas of impurity, add a spot of water and oxygen simultaneously, prevent that the decomposition product of impurity is blended in the purified hydrogen chloride gas.Its impurity is that byproduct hydrogen chloride gas wherein contains organic substances such as a spot of acetic acid at the monochlor(in)ate acetic acid of chlorine and acetic acid reaction preparation.In the presence of water vapour and oxygen, by hydrogen chlorine flame heating, oxidation operation changes into carbon dioxide, hydrogen and hydrogen chloride gas after decomposing fully, makes with extra care out hydrogen chloride gas.
According to the present invention,, during the purification refine hydrogen chloride gas, at first before purification of chlorinated hydrogen, measure containing amounts of hydrogen in the hydrogen chloride gas with hydrogen on-line monitoring instrument removing hydrogen in the burner internal combustion by hydrogen and oxygen.The content of hydrogen is no more than under the situation of 14% (v/v) in confirming hydrogen chloride gas, measure the hydrogen chloride gas that contains hydrogen and the volume of oxygen/air respectively by under meter, enter hydrogen and oxygen mol ratio content in the pipeline by the control of the under meter on the pipeline, in reaction, add a small amount of excess of oxygen, enter and carry out thorough mixing in the pipeline.Make to enter and carry out well-mixed hydrogen in the pipeline and the oxygen mol ratio is controlled at 2: 1~1.2 scopes.Hydrogen is provided: the proportioning ratio of oxygen can be 2: 1.1 dispensing oxygen.The supply form of oxygen can be that purity oxygen or air all can.Can carry out the emptying processing at subsequent processing because in reaction, add a small amount of excess of oxygen, can not bring potential safety hazard.
To contain the hydrogen chloride gas of hydrogen and a certain proportion of air/oxygen behind thorough mixing on the pipeline, enter the secondary flame damper, mol ratio is that 2: 1~1.2 hydrogen and oxygen mixed gas enter first step flame damper, and by behind the flame damper of the second stage, enter the first-stage burning device, hydrogen chloride gas and air/oxygen gaseous reaction mixture are at first-stage burning device conversion zone, allow hydrogen and the oxygen conversion zone in burner carry out combustion reactions and generate water vapor, the water vapor liquid heat-transfer medium separates with gas phase chlorination hydrogen from the other end of first-stage burning device, removes hydrogen.Then the hydrogen chloride gas behind the purifying is entered moisture eliminator, it is carried out drying treatment become anhydrous hydrogen chloride gas.If require purity higher to hydrogen chloride gas, can adopt polyphone two stage burner or multistage burner to burn more fully, can get the hydrogen chloride gas that purity is 99.99% (v/v).
Consult Fig. 2.Burner has the combustion chamber cylindrical shell 5 of a hydrogen supply gas/oxygen mixed gas conversion zone, be connected with at cylindrical shell 5 two ends, described combustion chamber for above-mentioned mixed gas catalytic combustion and purification of chlorinated hydrogen incendiary electrically heated storehouse 3, in described electrically heated storehouse 3, be provided with and make gas can contact the nichrome wire 2 that carries out combustion reactions fully.Be positioned at the parabolic center at two ends, 3 left and right sides, described electrically heated storehouse, be connected with the burner ingress pipe 1 and the burner delivery line 6 of straight through combustion chamber 3.Also be provided with the insulation jacket and water-in and the water outlet that prevent that the too high feeding water coolant of temperature of reaction from lowering the temperature on combustion chamber cylindrical shell 5 stack shells.Combustion chamber cylindrical shell 5 can be the housing of a cylinder body shape of being made by glass material or stainless steel metal material, and in it being one can carry out blended cooling room 7 by hydrogen supply/carrier of oxygen.Combustion chamber cylindrical shell 5 is provided with and feeds the insulation jacket 9 that water coolant is lowered the temperature.On the stack shell of insulation jacket 9, be provided with and prevent that temperature of reaction is too high, make insulation jacket 9 feed water coolants after, water-in 8 and the water outlet 4 that can lower the temperature to combustion chamber cylindrical shell 5.Water-in 8 is cooling fluid inlets, and water outlet 4 is outlets of cooling fluid.Cylindrical shell 5 two ports in combustion chamber are shaped on the normal ground joint that connects electrically heated storehouse, two ends 3.Electrically heated storehouse 3 is movably connected in the both sides of combustion chamber cylindrical shell 5 by the accurate ground joint at combustion chamber cylindrical shell 5 two ends.Electrically heated storehouse 3 removably connects in the normal ground joint at combustion chamber cylindrical shell 5 two ends.Be provided with in the electrically heated storehouse 3 and can make the directly metal electric heating silk of contact of inflow gas.Be positioned at the parabolic center at two ends, 3 left and right sides, electrically heated storehouse, connect burner ingress pipe 1 and burner delivery line 6.
Embodiment 1.Draw the hydrogen that hydrogen chloride gas contains 13.2% (v/v) with hydrogen on-line monitoring instrument mensuration, 30L enters pipeline by the under meter metering, with the 2.2L oxygen thorough mixing of another pipeline by the under meter metering, after mixed gas enters the one-level flame damper, behind the secondary flame damper, enter into and carry out combustion reactions in the first-stage burning device, generate the water of 0.17mol after the burning after measured.By the hydrogen chloride gas sampling analysis of moisture eliminator, hydrogen content is 0.14% (v/v) in the hydrogenchloride.
Embodiment 2.Draw the hydrogen that hydrogen chloride gas contains 13.5% (v/v) with hydrogen on-line monitoring instrument mensuration, 30L enters pipeline by the under meter metering, with the 2.3L oxygen thorough mixing of another pipeline by the under meter metering, after mixed gas enters the one-level flame damper, behind the secondary flame damper, enter into carry out combustion reactions in the first-stage burning device after, burning back gas enters into second stage burner and burns away, and generates the water of 0.18mol after the burning after measured.By the hydrogen chloride gas sampling analysis of moisture eliminator, hydrogen content is 0.01% (v/v) in the hydrogenchloride.
Claims (9)
1. the process for purification of a hydrogen chloride gas, has following technical characterictic: before purification of chlorinated hydrogen, at first hydrogen content in the hydrogen chloride gas is measured with hydrogen on-line monitoring instrument, be no more than at hydrogen content under the situation of 14% (v/v), measure the hydrogen chloride gas that contains hydrogen and the volume of oxygen/air respectively by under meter, enter hydrogen and oxygen mol ratio content in the pipeline by the control of the under meter on the pipeline; In reaction, add a small amount of excess of oxygen, make to enter and carry out well-mixed hydrogen in the pipeline and the oxygen mol ratio is controlled at 2: 1~1.2 scopes, mixed gas enters first step flame damper, and by behind the flame damper of the second stage, enter the first-stage burning device, hydrogen chloride gas and air/oxygen gaseous reaction mixture allow hydrogen and the oxygen conversion zone in burner carry out combustion reactions and generate water vapor at first-stage burning device conversion zone, remove hydrogen; At last the hydrogen chloride gas behind the purifying is carried out drying treatment, enter next step high-temp chlorination alkane production process.
2. the process for purification of hydrogen chloride gas as claimed in claim 1 is characterized in that, the supply form of oxygen is purity oxygen or air.
3. the process for purification of hydrogen chloride gas as claimed in claim 1, it is characterized in that, described burner has the combustion chamber cylindrical shell (5) of a hydrogen supply gas/oxygen mixed gas conversion zone, be connected with at described combustion chamber cylindrical shell (5) two ends for above-mentioned mixed gas catalytic combustion and purification of chlorinated hydrogen incendiary electrically heated storehouse (3), in described electrically heated storehouse (3), be provided with the nichrome wire (2) that gas can be contacted fully carry out combustion reactions.
4. the process for purification of hydrogen chloride gas as claimed in claim 3, it is characterized in that, cylindrical shell (5) two ports in described combustion chamber are respectively equipped with the normal ground joint that connects electrically heated storehouse (3), and electrically heated storehouse (3) are movably connected in the both sides of combustion chamber cylindrical shell (5) by the normal ground joint at combustion chamber cylindrical shell (5) two ends.
5. the process for purification of hydrogen chloride gas as claimed in claim 1 is characterized in that, described combustion chamber cylindrical shell (5) is provided with and feeds the water coolant insulation jacket (9) of lowering the temperature.
6. the process for purification of hydrogen chloride gas as claimed in claim 3, it is characterized in that, on the stack shell of insulation jacket (9), be provided with and prevent that temperature of reaction is too high, make insulation jacket (9) feed water coolant after, water-in (8) and the water outlet (4) that can lower the temperature to combustion chamber cylindrical shell (5).
7. the process for purification of hydrogen chloride gas as claimed in claim 3 is characterized in that, is positioned at the parabolic center at two ends, the left and right sides, described electrically heated storehouse (3), is connected with the burner ingress pipe (1) and the burner delivery line (6) of straight through combustion chamber 3.
8. the process for purification of hydrogen chloride gas as claimed in claim 3 is characterized in that, described combustion chamber cylindrical shell (5) is a cylindrical shell of being made by glass material or stainless steel metal material.
9. the process for purification of hydrogen chloride gas as claimed in claim 3 is characterized in that, has a hydrogen supply/carrier of oxygen to carry out blended cooling room (7) in the described combustion chamber cylindrical shell (5).
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CN2010102747618A CN102161474B (en) | 2010-09-08 | 2010-09-08 | Method for refining hydrogen chloride gas |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2016150869A (en) * | 2015-02-17 | 2016-08-22 | 住友精化株式会社 | Method for producing hydrogen chloride |
CN114436215A (en) * | 2021-12-29 | 2022-05-06 | 安徽华塑股份有限公司 | Dehydrogenation process of hydrogen chloride synthesis gas |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5497597A (en) * | 1978-01-20 | 1979-08-01 | Denki Kagaku Kogyo Kk | Purification of hydrochloric acid gas |
US6273008B1 (en) * | 1998-04-02 | 2001-08-14 | Tommy G. Taylor | Chlorinated hydrocarbon waste incinerator and valorization of chlorinated residuals process unit |
JP2002316803A (en) * | 2001-04-16 | 2002-10-31 | Nkk Corp | Method and facility for recovering hydrochloric acid from evolved gas of dechlorination treatment of chlorine-containing resin |
CN101115677A (en) * | 2005-02-08 | 2008-01-30 | 索维公司 | Method for purifying hydrogen chloride |
-
2010
- 2010-09-08 CN CN2010102747618A patent/CN102161474B/en not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5497597A (en) * | 1978-01-20 | 1979-08-01 | Denki Kagaku Kogyo Kk | Purification of hydrochloric acid gas |
US6273008B1 (en) * | 1998-04-02 | 2001-08-14 | Tommy G. Taylor | Chlorinated hydrocarbon waste incinerator and valorization of chlorinated residuals process unit |
JP2002316803A (en) * | 2001-04-16 | 2002-10-31 | Nkk Corp | Method and facility for recovering hydrochloric acid from evolved gas of dechlorination treatment of chlorine-containing resin |
CN101115677A (en) * | 2005-02-08 | 2008-01-30 | 索维公司 | Method for purifying hydrogen chloride |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2016150869A (en) * | 2015-02-17 | 2016-08-22 | 住友精化株式会社 | Method for producing hydrogen chloride |
CN114436215A (en) * | 2021-12-29 | 2022-05-06 | 安徽华塑股份有限公司 | Dehydrogenation process of hydrogen chloride synthesis gas |
CN114436215B (en) * | 2021-12-29 | 2023-12-29 | 安徽华塑股份有限公司 | Dehydrogenation process of hydrogen chloride synthesis gas |
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