WO1994001204A1 - Procede et dispositif de regulation de l'humidite d'un flux gazeux et simultanement d'elimination des gaz acides ou alcalins indesirables compris dans ce flux gazeux - Google Patents

Procede et dispositif de regulation de l'humidite d'un flux gazeux et simultanement d'elimination des gaz acides ou alcalins indesirables compris dans ce flux gazeux Download PDF

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Publication number
WO1994001204A1
WO1994001204A1 PCT/EP1993/001773 EP9301773W WO9401204A1 WO 1994001204 A1 WO1994001204 A1 WO 1994001204A1 EP 9301773 W EP9301773 W EP 9301773W WO 9401204 A1 WO9401204 A1 WO 9401204A1
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WO
WIPO (PCT)
Prior art keywords
membrane
gas flow
alkaline
gasses
acid
Prior art date
Application number
PCT/EP1993/001773
Other languages
English (en)
Inventor
Berend Philippus Ter Meulen
Original Assignee
Nederlandse Organisatie Voor Toegepast- Natuurwetenschappelijk Onderzoek (Tno)
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nederlandse Organisatie Voor Toegepast- Natuurwetenschappelijk Onderzoek (Tno) filed Critical Nederlandse Organisatie Voor Toegepast- Natuurwetenschappelijk Onderzoek (Tno)
Priority to JP6502960A priority Critical patent/JPH06510481A/ja
Priority to EP93915837A priority patent/EP0607387A1/fr
Publication of WO1994001204A1 publication Critical patent/WO1994001204A1/fr

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/22—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by diffusion
    • B01D53/229—Integrated processes (Diffusion and at least one other process, e.g. adsorption, absorption)
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/26—Drying gases or vapours
    • B01D53/268—Drying gases or vapours by diffusion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F3/00—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems
    • F24F3/12—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling
    • F24F3/14—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification
    • F24F2003/1435—Air-conditioning systems in which conditioned primary air is supplied from one or more central stations to distributing units in the rooms or spaces where it may receive secondary treatment; Apparatus specially designed for such systems characterised by the treatment of the air otherwise than by heating and cooling by humidification; by dehumidification comprising semi-permeable membrane
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F6/00—Air-humidification, e.g. cooling by humidification

Definitions

  • the invention relates to a method for regulating the humidity of a gas flow and purifying that gas flow of, for example, acid or alkaline gasses, whereby the gas flow is led along a side - the retentive side - of a membrane, through which water vapour can diffuse and on the other ⁇ side of which - the permeation side - a hydroscopic liquid flows.
  • a practical and continuously usable method of this sort is descri- 5 bed in US patent no. 4.915.838: in order to remove water vapour from air, the air flow which is to be dried is led along the retentive side of a micro-porous membrane.
  • the membrane which is used is a so-called hollow-fibre membrane.
  • a hydroscopic liquid flows on the permeation side of the membrane. 0 Water vapour from the gas flow diffuses through the pores of the mem ⁇ brane from the retentive side to the permeation side and is there ab ⁇ sorbed and carried off by the hydroscopic liquid.
  • the invention relates to a method with which the regulation of the humidity of an air flow and the removal therefrom of undesired gasses, which are absorbed well in alkaline, acid or neutral watery solutions, can be achieved simultaneously in a single process.
  • the method accor ⁇ ding to the invention is characterized to that end in that a membrane is used through which the gasses concerned which are to be removed can also diffuse and that the hydroscopic liquid is mixed with a watery component, in such a manner that the water content of the mixture is adjusted to the desired humidity balance of the gas flow which is to be treated and that the composition thereof is adjusted to the solubility therein of the, for example, acid and alkaline components which are to be removed from the gas flow.
  • the water content of the hydroscopic mixture is decisive for the humidity balance which is to be adjusted.
  • the membrane can allow water vapour to pass through in both directions - from the retentive side to the permeation side and vice-versa, water vapour can be both added to the gas flow which is to be treated and can be removed there- from.
  • the gas component(s) concerned from the retentive side of the membrane to the permeation side thereof, followed by absorption in the watery, possibly acid or alkaline com ⁇ ponent of the hydroscopic mixture which flows along the permeation side of the membrane that (those) gas component(s) are removed from the gas flow which is to be treated simultaneously with the adjustment of the humidity.
  • the watery component must be of such a com ⁇ position, that the solubility of the component which is to be removed is increased and/or is accelerated by a physical or chemical interac ⁇ tion.
  • the composition must be adjusted to the nature of the gasses which are to be removed. For example, strong or weak organic or anor ⁇ ganic acids or alkalines are dissolved therein. Good results are achieved with a hydroscopic liquid which consists of polar glycols, alcohols or glycerols such as triethyleneglycol or polyethyleneglycol or mixtures thereof. Watery electrolite solutions with hydroscopic qualities are also possible. In general it applies, that such a hydroscopic mixture, the hydroscopic liquid with the parts dissolved therein, must be chosen which is compatible with the membrane and module materials which are to be used.
  • the invention also includes a method to regenerate a hydroscopic mixture used for regulating the humidity during the process until it has the desired water content again. That method is characterized to that end in that the mixture is then first heated or cooled to a cer ⁇ tain temperature, it is then brought into contact via a membrane which is permeable for water vapour with a gas flow with a certain humidity, until equilibrium is reached and finally the mixture is cooled again, or respectively heated again, to the working temperature.
  • the membrane module which is to be used contains one or more mem ⁇ branes, which are micro-porous and hydrophobic.
  • Polypropylene for example, suffices in this respect.
  • they must have a suf ⁇ ficiently large exchange surface for the purpose; they may be hollo — fibre membranes, but also flat membranes can be applied. In principle it makes no difference on which side of the membrane the gas, or the liquid flow respectively, are led.
  • a hol ⁇ low-fibre membrane either the liquid flow or the gas flow can flow through the fibre.
  • a thin top layer consists, for example, of PDMS (silicon rubber) or polytrimethylsilylpropyne, or of thin gel layers on a polymer basis.
  • this top layer for both water va ⁇ pour and for the parts which are to be removed from the gas which is to be treated must be sufficiently large in order to ensure that an effec ⁇ tive removal is achieved.
  • Such a top layer may be hydrophobic or hydro- philic.
  • a membrane module wit one or more membranes through which both water vapour and the, fo example, acid or alkaline gasses, which are to be removed can diffuse, and equipped with means to lead the gas flow which is to be purifie and regulated as concerns humidity across it on the one side of th membrane(s), and to lead an acid, alkaline or neutral hydroscopic mix ture across it on the other side.
  • the membranes are then preferably micro-porous and hydrophobic, have a sufficiently large exchange surface and may be equipped with non-porous top layer with a sufficiently large permeability for th substances which are to diffuse through it.
  • Example 1 A humid nitrogen flow with an S ⁇ 2 content of 500 ppm was lead a 20 "C with a flow rate of 4 liters per minute through the fibres of hollow-fibre membrane module (type ENKA LM2P06), polypropylene fibres, microporous).
  • the membrane module has fibres with an internal diamete of 0.6 mm and a total membrane surface of 400 cm 2 .
  • the fibre bundle was surrounded on the outside by 0.25 1/min. of mixture of ethylene glycol and sodium carbonate solution.
  • the ratio o ethylene glycol and sodium carbonate solution in this mixture was 4:1 on a weight basis.
  • For the incoming nitrogen flow a relative humidity of approximately 94% was measured, with a dew point of 18.8 °C.
  • the SO2 concentration was brought to 500 ppm.
  • In the outgoing nitrogen flow a relative humidity of approximately 61% was measured, with a dew point of 12.1 °C.
  • a content of 0.5 ppm was measured as SO2 concentration of the outgoing nitrogen flow.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Treating Waste Gases (AREA)
  • Gas Separation By Absorption (AREA)

Abstract

Procédé et dispositif de régulation de l'humidité d'un flux gazeux et simultanément d'élimination des gaz acides ou alcalins indésirables compris dans ce flux gazeux. On fait passer le flux gazeux sur la face rétentive d'une membrane au travers de laquelle peut se diffuser de la vapeur d'eau. Un liquide hygroscopique s'écoule sur la face perméable de la membrane. On utilise une membrane au travers de laquelle peuvent se diffuser les gaz acides ou alcalins en question. Le liquide hygroscopique se mélange à un constituant aqueux dont on règle la teneur en humidité en fonction de l'égalisation d'humidité voulue dans le flux gazeux, et dont on règle la composition de manière à augmenter et/ou à accélérer la solubilité des constituants mélangés que l'on souhaite éliminer du flux gazeux.
PCT/EP1993/001773 1992-07-08 1993-07-02 Procede et dispositif de regulation de l'humidite d'un flux gazeux et simultanement d'elimination des gaz acides ou alcalins indesirables compris dans ce flux gazeux WO1994001204A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP6502960A JPH06510481A (ja) 1992-07-08 1993-07-02 ガス流の湿度を調整し同時にガス流から好ましくない酸性あるいはアルカリ性のガスを浄化する方法および装置
EP93915837A EP0607387A1 (fr) 1992-07-08 1993-07-02 Procede et dispositif de regulation de l'humidite d'un flux gazeux et simultanement d'elimination des gaz acides ou alcalins indesirables compris dans ce flux gazeux

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL9201226A NL9201226A (nl) 1992-07-08 1992-07-08 Werkwijze en inrichting voor het reguleren van de vochtigheid van een gasstroom en het tegelijkertijd zuiveren daarvan van ongewenste zure of basische gassen.
NL9201226 1992-07-08

Publications (1)

Publication Number Publication Date
WO1994001204A1 true WO1994001204A1 (fr) 1994-01-20

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1993/001773 WO1994001204A1 (fr) 1992-07-08 1993-07-02 Procede et dispositif de regulation de l'humidite d'un flux gazeux et simultanement d'elimination des gaz acides ou alcalins indesirables compris dans ce flux gazeux

Country Status (4)

Country Link
EP (1) EP0607387A1 (fr)
JP (1) JPH06510481A (fr)
NL (1) NL9201226A (fr)
WO (1) WO1994001204A1 (fr)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995015206A1 (fr) * 1993-12-01 1995-06-08 Gas Research Institute Procede d'elimination des emissions organiques
WO1995026225A1 (fr) 1994-03-25 1995-10-05 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Procede d'absorption de gaz au travers d'une membrane
NL9400483A (nl) * 1994-03-25 1995-11-01 Tno Werkwijze voor gas/vloeistof-absorptie met behulp van holle vezelmembranen.
WO1995034371A1 (fr) * 1994-06-15 1995-12-21 Nederlandse Organisatie Voor Toegepast- Natuurwetenschappelijk Onderzoek Tno Procede et dispositif d'extraction du gaz ammoniac d'un gaz
US5490884A (en) * 1994-09-09 1996-02-13 Tastemaker Method and system for extracting a solute from a fluid using dense gas and a porous membrane
WO1997019196A1 (fr) * 1995-11-22 1997-05-29 North Carolina State University Traitement par bioreacteur destine a l'elimination continue de composes organiques d'un flux de traitement en phase vapeur
US5797272A (en) * 1994-05-30 1998-08-25 F F Seeley Nominees Pty Ltd Vacuum dewatering of desiccant brines
US6083297A (en) * 1995-12-13 2000-07-04 Whatman, Inc. Gas dehydration membrane with low oxygen and nitrogen permeability
WO2002038250A1 (fr) * 2000-11-08 2002-05-16 Clearwater International, L.L.C. Deshydratation de gaz effectuee au moyen d'une membrane et d'une solution de formiate de potassium
WO2002044624A1 (fr) * 2000-12-01 2002-06-06 Daimlerchrysler Ag Dispositif d'humidification et de deshumidification en continu de l'air fourni dans des processus de fabrication et des installations de conditionnement de l'air
US6497749B2 (en) * 2001-03-30 2002-12-24 United Technologies Corporation Dehumidification process and apparatus using collodion membrane
US6517607B2 (en) * 2001-06-04 2003-02-11 Gas Technology Institute Method and apparatus for selective removal of a condensable component from a process stream with latent heat recovery
US6926829B2 (en) 2000-03-06 2005-08-09 Kvaerner Process Systems A.S. Apparatus and method for separating fluids through a membrane
US7625427B2 (en) 2002-12-02 2009-12-01 Molecular Products Limited Apparatus and process for carbon dioxide absorption
US8679230B2 (en) 2008-12-19 2014-03-25 Michael L. Strickland Reducing emissions of VOCs from low-pressure storage tanks

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10782261B2 (en) * 2014-03-25 2020-09-22 The Procter & Gamble Company Apparatus for sensing environmental humidity changes

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4147754A (en) * 1975-07-28 1979-04-03 General Electric Company System for selective removal of hydrogen sulfide from a mixture of gases
EP0308002A1 (fr) * 1987-09-09 1989-03-22 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Procédé et membrane pour éliminer de la vapeur d'eau à partir d'un mélange gaz/vapeur par perméation-vapeur
US4900448A (en) * 1988-03-29 1990-02-13 Honeywell Inc. Membrane dehumidification
EP0430331A1 (fr) * 1989-11-23 1991-06-05 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Purification d'air
WO1991015284A1 (fr) * 1990-04-03 1991-10-17 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Procede de separation utilisant une membrane et servant a deshydrater un melange de gaz, de vapeur ou de liquides par evaporation a travers une membrane, par penetration de vapeur ou degazage
US5084073A (en) * 1990-10-11 1992-01-28 Union Carbide Industrial Gases Technology Corporation Membrane drying process and system

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4147754A (en) * 1975-07-28 1979-04-03 General Electric Company System for selective removal of hydrogen sulfide from a mixture of gases
EP0308002A1 (fr) * 1987-09-09 1989-03-22 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Procédé et membrane pour éliminer de la vapeur d'eau à partir d'un mélange gaz/vapeur par perméation-vapeur
US4900448A (en) * 1988-03-29 1990-02-13 Honeywell Inc. Membrane dehumidification
EP0430331A1 (fr) * 1989-11-23 1991-06-05 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Purification d'air
WO1991015284A1 (fr) * 1990-04-03 1991-10-17 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Procede de separation utilisant une membrane et servant a deshydrater un melange de gaz, de vapeur ou de liquides par evaporation a travers une membrane, par penetration de vapeur ou degazage
US5084073A (en) * 1990-10-11 1992-01-28 Union Carbide Industrial Gases Technology Corporation Membrane drying process and system

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995015206A1 (fr) * 1993-12-01 1995-06-08 Gas Research Institute Procede d'elimination des emissions organiques
WO1995026225A1 (fr) 1994-03-25 1995-10-05 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Procede d'absorption de gaz au travers d'une membrane
NL9401233A (nl) * 1994-03-25 1995-11-01 Tno Werkwijze voor membraangasabsorptie.
NL9400483A (nl) * 1994-03-25 1995-11-01 Tno Werkwijze voor gas/vloeistof-absorptie met behulp van holle vezelmembranen.
US5749941A (en) * 1994-03-25 1998-05-12 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Method for gas absorption across a membrane
US5797272A (en) * 1994-05-30 1998-08-25 F F Seeley Nominees Pty Ltd Vacuum dewatering of desiccant brines
WO1995034371A1 (fr) * 1994-06-15 1995-12-21 Nederlandse Organisatie Voor Toegepast- Natuurwetenschappelijk Onderzoek Tno Procede et dispositif d'extraction du gaz ammoniac d'un gaz
NL9400976A (nl) * 1994-06-15 1996-01-02 Tno Werkwijze en inrichting voor het verwijderen van ammoniak uit gas.
US5490884A (en) * 1994-09-09 1996-02-13 Tastemaker Method and system for extracting a solute from a fluid using dense gas and a porous membrane
US5954858A (en) * 1995-11-22 1999-09-21 North Carolina State University Bioreactor process for the continuous removal of organic compounds from a vapor phase process stream
WO1997019196A1 (fr) * 1995-11-22 1997-05-29 North Carolina State University Traitement par bioreacteur destine a l'elimination continue de composes organiques d'un flux de traitement en phase vapeur
US6083297A (en) * 1995-12-13 2000-07-04 Whatman, Inc. Gas dehydration membrane with low oxygen and nitrogen permeability
US6926829B2 (en) 2000-03-06 2005-08-09 Kvaerner Process Systems A.S. Apparatus and method for separating fluids through a membrane
WO2002038250A1 (fr) * 2000-11-08 2002-05-16 Clearwater International, L.L.C. Deshydratation de gaz effectuee au moyen d'une membrane et d'une solution de formiate de potassium
WO2002044624A1 (fr) * 2000-12-01 2002-06-06 Daimlerchrysler Ag Dispositif d'humidification et de deshumidification en continu de l'air fourni dans des processus de fabrication et des installations de conditionnement de l'air
US6887303B2 (en) 2000-12-01 2005-05-03 Daimlerchrysler Ag Device for continuously humidifying and dehumidifying feed air
US6497749B2 (en) * 2001-03-30 2002-12-24 United Technologies Corporation Dehumidification process and apparatus using collodion membrane
US6517607B2 (en) * 2001-06-04 2003-02-11 Gas Technology Institute Method and apparatus for selective removal of a condensable component from a process stream with latent heat recovery
US7625427B2 (en) 2002-12-02 2009-12-01 Molecular Products Limited Apparatus and process for carbon dioxide absorption
US8679230B2 (en) 2008-12-19 2014-03-25 Michael L. Strickland Reducing emissions of VOCs from low-pressure storage tanks

Also Published As

Publication number Publication date
NL9201226A (nl) 1994-02-01
JPH06510481A (ja) 1994-11-24
EP0607387A1 (fr) 1994-07-27

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