CN1262333C - Method for cleaning, adsorbing bed by sucked air in sucking procedure in pressure varied adsorption - Google Patents
Method for cleaning, adsorbing bed by sucked air in sucking procedure in pressure varied adsorption Download PDFInfo
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- CN1262333C CN1262333C CN 03135128 CN03135128A CN1262333C CN 1262333 C CN1262333 C CN 1262333C CN 03135128 CN03135128 CN 03135128 CN 03135128 A CN03135128 A CN 03135128A CN 1262333 C CN1262333 C CN 1262333C
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Abstract
The present invention relates to a method for flushing an adsorption bed by using sucked air in the absolutely sucking course through changing pressure and adsorption, which relates to a method for separating, removing impurities and purification for mixed gas. The present invention aims to solve the problems that adsorbent in the existing method incompletely regenerates, or the recovery rate of purifying gas is low because the flushing gas is used for flushing. In the method, in the adsorption bed in which is adsorbent is contained, a configuration pipeline, a control valve and a pressure changing absorption device of a vacuum pump, the adsorption bed absorbs and regenerates selectivity gas of the mixed gas, and separates impurity gas. Thus, clean gas is obtained. The adsorption bed is at least provided with an air suction valve which is connected with the atmosphere. In the regeneration step and the pumping out step, the adsorption bed is flushed by air sucked by the air suction valve. In the pumping out step, the pressure of the adsorption bed is from 0.05 to 0.007MPa, the air quantity of sucked air is 5% to 50% of handling quantity of the mixed gas during adsorption. The present invention is suitable for separating and purifying the mixed gas and removing impurities of the mixed gas.
Description
Technical field
The present invention relates to the pressure swing absorption process of the separation impurity and purification of gaseous mixture, particularly the evacuation process utilization in pressure swing absorption process sucks air adsorbent bed is found time to add process of washing.
Background technology
Common pressure swing absorption process carries out in the pressure-swing absorption apparatus that the adsorbent bed of filled with adsorbent and configuring pipes thereof, control valve constitute, and pressure swing absorption process utilizes the adsorptive selectivity of adsorbent to gas, the pressure-dependent characteristic of adsorption capacity.Adsorption capacity raise when adsorbent raise at pressure, and adsorption capacity reduced desorption and regeneration when pressure reduced.In pressure-swing absorption process,, adopt find time desorption and regeneration and flushing desorption and regeneration or two kinds of process combined usually to the regeneration of adsorbent.The general desorption and regeneration technology of finding time that adopts under the condition that the purified gas rate of recovery is had relatively high expectations.In the desorption procedure of finding time, the desorption effect that is adsorbed on the component on the adsorbent is subjected to the influence of this component factor such as diffusion velocity on adsorbent.Therefore often desorption and regeneration is incomplete to the bigger component of adsorbance on adsorbent in pressure-swing absorption apparatus, causes the purity of purified gas to descend.In to the high pressure swing adsorption technique of purified gas purity requirement, adopt the returning part purified gas in evacuation step, adsorbent bed to be washed, can improve the purity of purified gas, but returning of purified gas will cause the purified gas rate of recovery to reduce by 5～30%.
Summary of the invention
In view of above-mentioned, what the object of the present invention is to provide a kind of purity that can improve purified gas, the rate of recovery utilizes the method that sucks the air douche adsorbent bed in the evacuation process of transformation absorption.
The present invention adopts the inlet valve that configuration directly communicates with atmosphere on adsorbent bed, and open inlet valve in evacuation process in existing pressure-swing absorption apparatus, and the suction atmosphere is found time to add flushing to adsorbent bed and realized its purpose.
The method (referring to accompanying drawing) that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing of the present invention, in the pressure-swing absorption apparatus of the adsorbent bed that filled with adsorbent is arranged and configuring pipes, control valve and vavuum pump, the adsorbent bed operation is to the selective gas absorption and the regenerative process of gaseous mixture, removing impurities gas, obtain purified gas, it is characterized in that the inlet valve that adsorbent bed has at least one to be communicated with atmosphere, in the evacuation step of regenerative process, suck air adsorbent bed is washed through inlet valve.
The adsorbent bed pressure of above-mentioned evacuation step is 0.05～0.007MPa, the tolerance that sucks air during for absorption the gaseous mixture treating capacity 5%～50%.The tolerance of above-mentioned adsorbent bed pressure, suction air is determined according to purifying precision and gas impurity content to be clean.
Above-mentioned evacuation step is found time to adsorbent bed with vavuum pump, sucks the air douche adsorbent bed with opening inlet valve after 40%～95% desorb of absorption impurity, closes inlet valve after adsorbent holomorphosis, extracts the air that remains on the adsorbent out adsorbent bed.
Above-mentioned adsorbent bed circular flow, is reversely put pressures, is found time to add suction air douche, the step of boosting at each circulation experience absorption successively.
Above-mentioned adsorbent bed circular flow, is reversely put pressures, is found time to add and suck air douche, at least once equal voltage rise, the step of boosting at each circulation experience absorption successively, at least once all pressure drops.
The present invention compared with prior art, the inventive method is in the evacuation step of the regenerative process of transformation absorption, with vavuum pump adsorbent bed is found time earlier, the impurity that the dividing potential drop of impurity is adsorbed on the adsorbent major part in the reduction adsorbent bed is separated the sucking-off adsorbent bed, open the inlet valve that communicates with atmosphere again, sucking atmosphere when finding time washes adsorbent bed, make adsorbent obtain more completely regeneration, before finishing, evacuation step closes the inlet valve that communicates with atmosphere, the air that utilizes vavuum pump will remain on the adsorbent is extracted adsorbent bed out, thereby, have and can improve the adsorbent reactivation effect, improve the purity of purified gas, the advantage of the rate of recovery.
When using the inventive method from the mist of modified atmosphere fresh-keeping storage discharging, to remove ethene, find time to add flushing owing to suck air, thereby the concentration of ethene can be controlled to below the 5ppm in the purified gas of acquisition in evacuation step.Simultaneously do not lose nitrogen, guarantee that nitrogen has the high rate of recovery.
The present invention is applicable to the separation impurity and purification to gaseous mixture.
Below, with embodiment and accompanying drawing thereof the present invention is further described again.
Description of drawings
Accompanying drawing is a kind of schematic flow sheet that utilizes the method that sucks the air douche adsorbent bed in the evacuation process of transformation absorption of the present invention.
The specific embodiment
Embodiment 1
A kind of method that sucks the air douche adsorbent bed of utilizing in the evacuation process of transformation absorption of the present invention is used for removing ethene from the gaseous mixture of modified atmosphere fresh-keeping storage discharging.
As shown in drawings, present embodiment adopts common adsorbent bed A and adsorbent bed B, the pipeline 10,20,30,40 that is communicated with adsorbent bed A and adsorbent bed B configuration and control valve 1A, 2A, 3A, 4A, 1B, 2B, 3B, 4B respectively, wherein control valve 4A, 4B are the inlet valves that respectively A tower and B tower is communicated with atmosphere, the vavuum pump D that are communicated with control valve 3A and 3B etc. constitute pressure swing adsorption system, filled with adsorbent active carbon in adsorbent bed.
Pressure swing adsorption system is operation under computer program control, two adsorbent beds hocket adsorption process and regenerative process.Adsorption process operation adsorption step, the regenerative process operation is reverse puts pressures, find time to add suction air douche, the step of boosting.Each adsorbent bed circular flow, is reversely put pressures, is found time to add suction air douche, the step of boosting at each circulation experience absorption successively.To contain ethene 5000ppm, the modified atmosphere fresh-keeping storage tail gas 500Nm of carbon dioxide 3%
3/ h is pressurized to 0.15MPa by air blast, by pipeline 10, enter the adsorbent bed A that is in adsorption step through valve 1A, the ethene in the gas is loaded in the adsorbents adsorb in the adsorbent bed, and the purified gas that obtains is sent into modified atmosphere fresh-keeping storage through pipeline 20 again through valve 2A and recycled.Open with control valve 1A, 2A that adsorbent bed A links this moment, and control valve 3A, 4A then are in closed condition.When adsorbent bed A was in adsorption process and promptly carries out adsorption step, adsorbent bed B then was in regenerative process, and promptly adsorbent bed B enters regenerative process after executing first step adsorption step.Second step of adsorbent bed B is the reverse pressure step of putting, control valve 1B, the 2B, the 3B that link to each other with adsorbent bed B all are in closed condition, ethene inhaled saturated by adsorbent in the adsorbent bed B, follow opening controlling valve 3B, the gas of certain pressure in the adsorbent bed is discharged outside the adsorbent bed by pipeline 40, the 3rd step of adsorbent bed B tower adds rinsing step for finding time, open inlet valve 4B and vavuum pump D, adsorbent bed is found time and suck air through inlet valve 4B the adsorbent that has adsorbed ethene, carbon dioxide is regenerated.Close inlet valve 4B earlier before evacuation step finishes, continuing to find time to make the air that remains on the adsorbent to extract adsorbent bed out by vavuum pump to adsorbent bed does not increase with oxygen content in the nitrogen that guarantees to return air-conditioned cold store.The 4th step of adsorbent bed B tower is the step of boosting, and opening controlling valve 2B, purified gas progressively boost to adsorbent bed B, reach till the adsorptive pressure, immediately closed control valve 2B.Adsorbent bed B carries out adsorption step and enters adsorption process then, and this moment, adsorbent bed A entered regenerative process.Two adsorbent beds like this continuously alternately the circulation adsorb, regenerative process.
The time of the adsorption step of present embodiment is 6 minutes, and in the regenerative process, reverse putting pressed step 0.5 minute, found time to add and suck air douche step 5 minute, comprising sucking air douche 4 minutes, and the step 0.5 of boosting minute.Contain ethene＜5ppm in the purified gas, directly return modified atmosphere fresh-keeping storage and recycle.Rate of recovery of nitrogen 96%.
Embodiment 2
A kind of method that sucks the air douche adsorbent bed of utilizing in the evacuation process of transformation absorption of the present invention, present embodiment adopt the pressure swing adsorption system that 4 adsorbent beds arranged similar with embodiment 1, to 2000Nm
3The nitrogen that contains 15% carbon dioxide of/h carries out purified treatment.Adsorptive pressure 0.4MPa, evacuation step pressure 0.03MPa.Adsorbent is an active carbon.4 adsorbent beds continuously alternately the processing steps that carry out of circulation be: absorption, all pressure drops, reversely put pressures, find time to add and suck air douche (suction air capacity 600Nm
3/ h), all voltage rises, boost.Carbonated in the purified gas＜0.01%, rate of recovery of nitrogen 98%.
Embodiment 3
A kind of method that sucks the air douche adsorbent bed of utilizing in the evacuation process of transformation absorption of the present invention, present embodiment adopt the pressure swing adsorption system that 4 adsorbent beds arranged similar with embodiment 1, to 3000Nm
3The nitrogen that contains 10% carbon dioxide of/h carries out purified treatment.Adsorptive pressure 0.6MPa, vacuum step pressure 0.02MPa.Adsorbent is an active carbon 30%+ Kiselgel A 60%+ activated alumina 10%.4 adsorbent beds continuously alternately the processing steps that carry out of circulation be: absorption, once all pressure drops, the equal pressure drop of secondary, reversely put pressures, find time to add and suck air douche (suction air capacity 350Nm
3/ h), the equal voltage rise of secondary, once all voltage rises, the step of boosting.Carbonated in the purified gas after the processing＜0.005%, rate of recovery of nitrogen 98.5%.
Embodiment 4
A kind of method that sucks the air douche adsorbent bed of utilizing in the evacuation process of transformation absorption of the present invention, present embodiment adopt the pressure swing adsorption system that 6 adsorbent beds arranged similar with embodiment 1, to 2500Nm
3The nitrogen that contains 20% carbon dioxide of/h carries out purified treatment.Adsorptive pressure 0.8MPa, vacuum step pressure 0.02MPa.Adsorbent is a property charcoal 30%+ Kiselgel A 40%+ activated alumina 20%.6 adsorbent beds are the processing steps that carry out of circulation alternately continuously: absorption, once all pressure drops, the equal pressure drop of secondary, three equal pressure drops, reversely put pressures, find time to add and suck air douche (suction air capacity 1250Nm
3/ h), three equal voltage rises, the equal voltage rise of secondary, once all voltage rises, boost.Carbonated in the purified gas after the processing＜0.005%, rate of recovery of nitrogen 98%.
Embodiment 5
A kind of method that sucks the air douche adsorbent bed of utilizing in the evacuation process of transformation absorption of the present invention, present embodiment adopt the pressure swing adsorption system that 8 adsorbent beds arranged similar with embodiment 1, to 10000Nm
3The nitrogen that contains 10% carbon dioxide of/h purifies.Adsorptive pressure 2.0MPa, vacuum step pressure 0.03MPa.Adsorbent is an active carbon 60%+ Kiselgel A 20%+ activated alumina 20%.8 adsorbent beds are the processing steps that carry out of circulation alternately continuously: absorption, once all pressure drops, the equal pressure drop of secondary, three equal pressure drops, reverse putting are pressed step, are found time to add and suck air douche and (suck air capacity 500Nm
3/ h), three equal voltage rises, the equal voltage rise of secondary, once all voltage rises, the step of boosting.Handle carbonated＜0.01% in the after-purification gas, rate of recovery of nitrogen 98.5%.
Embodiment 6
A kind of method that sucks the air douche adsorbent bed of utilizing in the evacuation process of transformation absorption of the present invention, present embodiment adopt the pressure swing adsorption system that 8 adsorbent beds arranged similar with embodiment 1, to 8000Nm
3The nitrogen that contains 10% carbon dioxide of/h purifies.Adsorptive pressure 2.0MPa, vacuum step pressure 0.025MPa.Adsorbent is an active carbon 60%+ Kiselgel A 20%+ activated alumina 20%.8 adsorbent beds are the processing steps that carry out of circulation alternately continuously: absorption, once all pressure drops, the equal pressure drop of secondary, three equal pressure drops, four equal pressure drops, reverse putting are pressed step, are found time to add and suck air douche and (suck air capacity 500Nm
3/ h), four equal voltage rises, three equal voltage rises, the equal voltage rise of secondary, once all voltage rises, the step of boosting.Handle carbonated＜0.015% in the after-purification gas, rate of recovery of nitrogen 98.5%.
Embodiment 7
A kind of method that sucks the air douche adsorbent bed of utilizing in the evacuation process of transformation absorption of the present invention, present embodiment adopt the pressure swing adsorption system that 10 adsorbent beds arranged similar with embodiment 1, to 15000Nm
3The nitrogen that contains 8% carbon dioxide of/h purifies.Adsorptive pressure 2.3MPa, vacuum step pressure 0.025MPa.Adsorbent is an active carbon 50%+ Kiselgel A 30%+ activated alumina 20%.10 adsorbent beds are the processing steps that carry out of circulation alternately continuously: absorption, once all pressure drops, the equal pressure drop of secondary, three equal pressure drops, four equal pressure drops, five equal pressure drops, reverse putting are pressed step, are found time to add and suck air douche and (suck air capacity 500Nm
3/ h), five equal voltage rises, four equal voltage rises, three equal voltage rises, the equal voltage rise of secondary, once all voltage rises, the step of boosting.Handle carbonated＜0.02% in the after-purification gas, rate of recovery of nitrogen 98.5%.
Claims (9)
1, a kind of method that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing, at adsorbent bed that filled with adsorbent is arranged and configuring pipes thereof, in the pressure-swing absorption apparatus of control valve and vavuum pump, the adsorbent bed operation is to the selective gas absorption and the regenerative process of gaseous mixture, removing impurities gas, obtain purified gas, it is characterized in that the inlet valve that adsorbent bed has at least one to be communicated with atmosphere, sucking air through inlet valve in the evacuation step of regenerative process washes adsorbent bed, the pressure of the adsorbent bed of evacuation step is 0.05-0.007MPa, the 5%-50% of gaseous mixture treating capacity when the tolerance of suction air is absorption.。
2, require the 1 described method that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing according to uncle's profit, it is characterized in that said evacuation step finds time to adsorbent bed with vavuum pump, suck the air douche adsorbent bed with opening inlet valve after 40%～95% desorb of absorption impurity, after adsorbent holomorphosis, close inlet valve, extract the air that remains on the adsorbent out adsorbent bed.
3, the method that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing according to claim 1 and 2, it is characterized in that said adsorbent bed circular flow, each circulation experience absorption successively, reversely put pressures, find time to add suction air douche, the step of boosting.
4, the method that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing according to claim 1 and 2, it is characterized in that said adsorbent bed circular flow, each circulation experience absorption successively, at least once all pressure drops, reversely put pressures, find time to add and suck air douche, at least once equal voltage rise, the step of boosting.
5, the method that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing according to claim 1 and 2, it is characterized in that said adsorbent bed circular flow, each circulation experience absorption successively, once all pressure drops, reversely put pressures, find time to add and suck air douche, once equal voltage rise, the step of boosting.
6, the method that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing according to claim 1 and 2, it is characterized in that 4 circular flows of said adsorbent bed, each circulation experience absorption successively, once all pressure drops, the equal pressure drop of secondary, reversely put pressures, find time to add and suck air douche, the equal voltage rise of secondary, once equal voltage rise, the step of boosting.
7, the method that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing according to claim 1 and 2, it is characterized in that said adsorbent bed 6 or 8 circular flows, each circulation experience absorption successively, once all pressure drops, the equal pressure drop of secondary, three equal pressure drops, reversely put pressures, find time to add and suck air douche, three equal voltage rises, the equal voltage rise of secondary, once equal voltage rise, the step of boosting.
8, the method that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing according to claim 1 and 2, it is characterized in that 8 circular flows of said adsorbent bed, each circulation experience absorption successively, one. inferior equal pressure drop, the equal pressure drop of secondary, three equal pressure drops, four equal pressure drops, reversely put pressures, find time to add and suck air douche, four equal voltage rises, three equal voltage rises, the equal voltage rise of secondary, once equal voltage rise, the step of boosting.
9, the method that sucks the air douche adsorbent bed of in the evacuation process of transformation absorption, utilizing according to claim 1 and 2, it is characterized in that 10 circular flows of said adsorbent bed, each circulation experience absorption successively, once all pressure drops, the equal pressure drop of secondary, three equal pressure drops, four equal pressure drops, five equal pressure drops, reversely put pressures, find time to add and suck air douche, five equal voltage rises, four equal voltage rises, three equal voltage rises, the equal voltage rise of secondary, once equal voltage rise, the step of boosting.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03135128 CN1262333C (en) | 2003-06-06 | 2003-06-06 | Method for cleaning, adsorbing bed by sucked air in sucking procedure in pressure varied adsorption |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03135128 CN1262333C (en) | 2003-06-06 | 2003-06-06 | Method for cleaning, adsorbing bed by sucked air in sucking procedure in pressure varied adsorption |
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| Publication Number | Publication Date |
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| CN1552506A CN1552506A (en) | 2004-12-08 |
| CN1262333C true CN1262333C (en) | 2006-07-05 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 03135128 Expired - Lifetime CN1262333C (en) | 2003-06-06 | 2003-06-06 | Method for cleaning, adsorbing bed by sucked air in sucking procedure in pressure varied adsorption |
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| CN102179129B (en) * | 2011-01-14 | 2013-03-13 | 海湾环保工程（北京）股份有限公司 | Treatment process for absorbed condensate waste gas |
| CN106861364A (en) * | 2017-02-21 | 2017-06-20 | 深圳市宸瀞环境科技有限公司 | A kind of radon gas remove device |
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Address after: Chengdu hi tech Zone Technology Innovation Service Center, No.5 Gaopeng Avenue, Chengdu hi tech Zone, Sichuan 610225 Patentee after: Haohua Chemical Technology Group Co.,Ltd. Address before: 445 box 610225, Airport Road, Sichuan, Chengdu Patentee before: SICHUAN TIANYI SCIENCE AND TECHNOLOGY Co.,Ltd. |
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Effective date of registration: 20200727 Address after: No. 5 high tech Zone Gaopeng road in Chengdu city of Sichuan Province in 610225 Patentee after: SOUTHWEST RESEARCH & DESIGN INSTITUTE OF CHEMICAL INDUSTRY Address before: Chengdu hi tech Zone Technology Innovation Service Center, No.5 Gaopeng Avenue, Chengdu hi tech Zone, Sichuan 610225 Patentee before: Haohua Chemical Technology Group Co.,Ltd. |
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Granted publication date: 20060705 |