WO1994026391A1 - Traitement de gaz industriel - Google Patents

Traitement de gaz industriel Download PDF

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Publication number
WO1994026391A1
WO1994026391A1 PCT/SE1994/000447 SE9400447W WO9426391A1 WO 1994026391 A1 WO1994026391 A1 WO 1994026391A1 SE 9400447 W SE9400447 W SE 9400447W WO 9426391 A1 WO9426391 A1 WO 9426391A1
Authority
WO
WIPO (PCT)
Prior art keywords
gas
liquid
treatment
drops
sound
Prior art date
Application number
PCT/SE1994/000447
Other languages
English (en)
Inventor
Bengt Nilsson
Olle Wennberg
Original Assignee
Kvaerner Pulping Technologies Ab
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 Kvaerner Pulping Technologies Ab filed Critical Kvaerner Pulping Technologies Ab
Priority to AU68106/94A priority Critical patent/AU6810694A/en
Priority to EP94916458A priority patent/EP0699102A1/fr
Publication of WO1994026391A1 publication Critical patent/WO1994026391A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D51/00—Auxiliary pretreatment of gases or vapours to be cleaned
    • B01D51/02—Amassing the particles, e.g. by flocculation
    • B01D51/06—Amassing the particles, e.g. by flocculation by varying the pressure of the gas or vapour
    • B01D51/08—Amassing the particles, e.g. by flocculation by varying the pressure of the gas or vapour by sound or ultrasonics
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D47/00—Separating dispersed particles from gases, air or vapours by liquid as separating agent
    • B01D47/06—Spray cleaning
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D47/00—Separating dispersed particles from gases, air or vapours by liquid as separating agent
    • B01D47/10—Venturi scrubbers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D49/00—Separating dispersed particles from gases, air or vapours by other methods
    • B01D49/006—Separating dispersed particles from gases, air or vapours by other methods by sonic or ultrasonic techniques
    • 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
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/46—Removing components of defined structure
    • B01D53/48—Sulfur compounds
    • B01D53/50—Sulfur oxides
    • B01D53/501—Sulfur oxides by treating the gases with a solution or a suspension of an alkali or earth-alkali or ammonium compound
    • B01D53/504—Sulfur oxides by treating the gases with a solution or a suspension of an alkali or earth-alkali or ammonium compound characterised by a specific device
    • 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
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/46—Removing components of defined structure
    • B01D53/48—Sulfur compounds
    • B01D53/52—Hydrogen sulfide
    • 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
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/08—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
    • B01J19/10—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing sonic or ultrasonic vibrations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2259/00—Type of treatment
    • B01D2259/80—Employing electric, magnetic, electromagnetic or wave energy, or particle radiation
    • B01D2259/816—Sonic or ultrasonic vibration

Definitions

  • the present invention relates to a method of continuously treating a gas obtained from an industrial process, to separate particles and/or liquid and/or gaseous substances from the gas and, if applicable, to transfer heat from or to the gas, the gas being introduced into a treatment chamber and brought into contact with at least one treating liquid which is suspended in the gas in the form of drops that absorb said particles and substances and receive or emit heat from and to the gas, respectively, said drops then being collected and the liquid thus collected being removed via an outlet which is spaced from an outlet for removing the gas cleaned, the amount of the treating liquid supplied being sufficient to obtain a state of equilibrium between gas and liquid in the treatment chamber.
  • Transfer resistance always exists when mass or heat is being transferred between two media. This resistance is of great significance to the efficiency of a process step and if it can be reduced efficiency will be improved.
  • the object of the present invention is to provide a method of continuously treating a process gas, which will result in improved transfer of heat and mass between gas phase and liquid phase, the gas phase of which being the continuous phase, and in improved separation of particles out of the gas.
  • the method according to the invention is characterized in that the treatment is performed while the gas is being exposed to infra-sound.
  • the gas is exposed to infra-sound having a frequency of at most 150 Hz, preferably at most 40 Hz and most preferred at most 20 Hz.
  • the sound intensity in the zone for absorption and transfer of heat exceeds 120 dB, preferably at least 140 dB.
  • the infra-sound is generated by at least one infra-sound generator.
  • the process gas contains sulphurous gases, such as SO2 and H2S, which are absorbed by liquid drops obtained from an alkaline water solution.
  • the process gas suitably contains particles which have been formed upon sublimation of vaporized substances and which are absorbed by the liquid drops.
  • the treatment is performed in a Venturi scrubber or a spray tower scrubber.
  • the treatment is performed as a selective absorption, absorption of one component in the process gas being in the first place limited by the convective mass transport, whereas absorption of other components, absorption of which is undesired, is limited by other parameters such as reaction velocities in the liquid phase.
  • the process gas contains H2S and CO2, and H2S is absorbed selectively by the alkali-containing liquid drops, while CO2 substantially accompanies the cleaned gas out of the treatment chamber.
  • the process gas has a higher temperature than the treatment liquid and heat is absorbed by the liquid drops moving downwards in counterflow to or concurrent with the process gas in a scrubber, preferably a spray tower scrubber.
  • the gas originates from a combustion process for sulphite waste liquor containing SO2•
  • the gas originates from an MgO boiler containing SO2 and the absorption liquid contains alkali in the form of hydrated MgO.
  • the treatment is carried out at a pressure in the treatment chamber of from atmospheric pressure up to 150 bar.
  • Figure 1 shows schematically a gas washing apparatus for treating combustion gas with suspended liquids at various levels.
  • Figure 2 shows schematically a Venturi scrubber for cleaning flue gas from a magnesium sulphite steam boiler.
  • FIG. 1 it is shown schematically therein an apparatus for treating a combustion gas recovered when gasifying black liquor in a gasification reactor containing gaseous substances or components including CO, H2, H2S, CO2 and H2O.
  • the apparatus is in the form of a gas washing apparatus including a closed vertical cylindrical vessel 1 having a washing chamber 2.
  • the combustion gas is transferred to the vessel from the gasification reactor (not shown) via a pipe 3 and is introduced in the lower part of the washing chamber 2.
  • the combustion gas flows up through the washing chamber and washed gas leaves the top of the vessel via a pipe 4 to be used as combustion gas and/or in the production of chemicals.
  • Alkali liquid such as green liquor
  • a pipe 5 provided with openings in the form of a plurality of nozzles 6 at a central level in the washing chamber 2, from which the alkali liquid is fed out as liquid drops.
  • Two more sets of nozzles 7, 8 are arranged at different levels above the first-mentioned liquor nozzles 6.
  • a pipe 9 is connected to the lower of these two additional sets of nozzles 7, 8 for the supply of water containing NaOH or Na2C03, and a pipe 10 is connected to the upper nozzles 8 for the supply of water containing no additives, the water being fed out of these nozzles as drops.
  • the liquid drops fall down by their own weight through the washing chamber 2, encountering the gas flowing upwards, and then collecting at the bottom of the vessel 1.
  • the liquid collected is fed back to the gasification reactor via a pipe 26 to be mixed with the green liquor therein.
  • the gas washing apparatus is equipped with a sound generator 11, the resonance tube 12 of which is connected to the vessel 1 and has its orifice in the washing chamber 2.
  • the resonance tube 12 is suitably inclined somewhat downwardly as illustrated in Figure 1, thus preventing liquid from entering the sound generator. If desired one or several more sound generators can be connected to the gas washer.
  • a bell-bottom is arranged in the upper part of the vessel, just above the nozzles 7, and weak liquor or similar alkaline liquid is supplied via pipe 10 and nozzles 8 and then removed from the bell-bottom which forms a liquid lock and through which the gas is pressed upwardly to be subjected to a washing step.
  • a sound generator is also arranged in the space above the bell-bottom.
  • FIG. 2 shows schematically an apparatus for treating a flue gas obtained on combustion of concentrated spent liquor in a magnesium sulphite steam boiler, said gas having a high sulphur dioxide content.
  • the apparatus is in the form of a Venturi scrubber in which the flue gas is cleaned with liquid in order to recover the sulphur.
  • the Venturi scrubber comprises a closed vertical Venturi vessel 13 enclosing a cleaning chamber 14.
  • the flue gas is transferred from the MgO steam boiler (not shown) to the Venturi vessel via a pipe 15 and is introduced at the upper end of the Venturi vessel 13, thereafter flowing down through the cleaning chamber 14.
  • the lower end of the Venturi vessel 13 opens via a connection 16 into a vertical separation vessel 17 through which the cleaned gas flows upwards to be discharged via a conduit 18.
  • Liquid is supplied via a pipe 19 connected to one or more downwardly directed nozzles 20 located in the Venturi neck 21.
  • the liquid is supplied through the nozzles 20 in the form of drops which thus move concurrent with the flue gas.
  • the liquid drops accompany the flue gas and are collected at the bottom of the adjacent separation vessel 17, and a part of the liquid collected is fed out via a circulation pipe 22 which is connected to the inlet pipe 19 for mixing with clean liquid, while the other part is fed out via a level pipe 23 as scrubbing liquid for the recovery of sulphate catched therein.
  • the liquid supplied suitably contains alkali additives, such as sodium hydroxide or sodium carbonate, in order to absorb sulphur dioxide and thus influence the sulphur dioxide content in the flue gas.
  • the Venturi scrubber is equipped with a sound generator 24, the resonance tube opens into the cleaning chamber 14 a little way below the Venturi neck 21.
  • the resonance tube 25 is suitably inclined downwardly as illustrated in Figure 2. If desired one or more additional sound generators can be connected to the Venturi scrubber. They should be located after the Venturi neck because the active mass and heat transfer zone extends from the Venturi neck and downwardly. A significant pressure drop also occurs in the Venturi neck, which also entails sound losses.
  • the sound generators 11, 24 are of the type that generate low-frequency sound, i.e. infra-sound, with a frequency of at most 150 Hz, preferably at most 40 Hz and most preferred at most 20 Hz.
  • the sound intensity must be sufficiently high to ensure improved mass and heat transfer.
  • the sound level should exceed 120 dB, preferably at least 140 dB, in the zone where mass and heat transfer occurs.
  • the gas must constitute the continuous phase if the infra-sound is to be able to reproduce itself right up to the contact surface between gas and liquid.
  • the contact means i.e. the treatment vessel, must have a relatively large free volume.
  • the conditions in the nozzle and Venturi scrubbers described above are very favourable to enable the infra-sound to reproduce itself to all the places where liquid and gas come into contact with each other. Contact means in the form of filler columns may therefore be unsuitable since the sound will be absorbed by the packing material therein.
  • CO2 shall as far as possible pass straight through the scrubber without reacting with the treating liquid or the scrubber liquid.
  • CO2 absorption is mainly kinetic-controlled whereas H2S absorption is diffusion-controlled.
  • the present invention with infra-sound exposure disintegrating the diffusion layers enables both control and intensification of the desired absorption process. This in turn means that the selectivity with regard to H2S in relation to CO2 is improve .
  • the liquid is sprayed into the upper half of the scrubber and the liquid drops formed fall downwardly while the gas rises, thereby producing counterflow contact.
  • the liquid drops will have a velocity in relation to the gas.
  • the relative velocity between gas and liquid drops contributes to the mass and heat transfer.
  • the liquid drops may have considerably higher velocity than lower down where the liquid drops are retarded by the flow resistance in the gas.
  • the method according to the invention can be repeated in one or more treatment chambers of the type described located consecutively.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Biomedical Technology (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Toxicology (AREA)
  • Organic Chemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Gas Separation By Absorption (AREA)
  • Treating Waste Gases (AREA)

Abstract

L'invention concerne un procédé de traitement continu d'un gaz obtenu à partir d'un procédé industriel, afin de séparer des particules et/ou des substances liquides et/ou gazeuses du gaz et, s'il convient, afin de transférer de la chaleur vers le gaz ou à partir de celui-ci, le gaz étant introduit dans une chambre de traitement (2) et mis au contact d'au moins un liquide de traitement en suspension dans le gaz sous la forme de gouttelettes absorbant lesdites particules et substances et recevant ou émettant de la chaleur depuis le gaz et vers celui-ci, respectivement. Les gouttelettes sont collectées, et du liquide ainsi que du gaz épuré sont extraits à travers différentes sorties (26, 4). Le liquide de traitement est fourni en une quantité suffisante pour obtenir un état d'équilibre entre les deux phases. Selon l'invention, le traitement est exécuté tandis que le gaz est exposé à des infrasons.
PCT/SE1994/000447 1993-05-19 1994-05-13 Traitement de gaz industriel WO1994026391A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU68106/94A AU6810694A (en) 1993-05-19 1994-05-13 Treating process gas
EP94916458A EP0699102A1 (fr) 1993-05-19 1994-05-13 Traitement de gaz industriel

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9301713A SE508789C2 (sv) 1993-05-19 1993-05-19 Behandling av processgas
SE9301713-5 1993-05-19

Publications (1)

Publication Number Publication Date
WO1994026391A1 true WO1994026391A1 (fr) 1994-11-24

Family

ID=20389987

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE1994/000447 WO1994026391A1 (fr) 1993-05-19 1994-05-13 Traitement de gaz industriel

Country Status (5)

Country Link
EP (1) EP0699102A1 (fr)
AU (1) AU6810694A (fr)
CA (1) CA2163236A1 (fr)
SE (1) SE508789C2 (fr)
WO (1) WO1994026391A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004041413A2 (fr) * 2002-11-01 2004-05-21 Board Of Regents Stimulation acoustique d'un systeme de diffusion de vapeur et procede associe
US7150779B2 (en) 2002-04-26 2006-12-19 Board Of Regents, The University Of Texas System Modulated acoustic agglomeration system and method
WO2015127518A1 (fr) * 2014-02-25 2015-09-03 SOVEX Em EOOD Procédé d'épuration de gaz de combustion et appareils pour sa mise en œuvre
CN107158856A (zh) * 2017-05-25 2017-09-15 华北电力大学 一种化学团聚联合声波团聚去除燃煤烟气细小颗粒物的方法
CN109126333A (zh) * 2018-09-11 2019-01-04 宁夏宝丰能源集团股份有限公司 气体净化装置
CN111036006A (zh) * 2019-12-24 2020-04-21 上海海事大学 一种声波增强的船舶废气脱硫及颗粒物去除装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1330870A (en) * 1969-12-10 1973-09-19 Braxton Corp Process and apparatus for removing unwanted particles from a gas
DE3507596A1 (de) * 1985-03-04 1986-09-04 Wehrle-Werk Ag, 7830 Emmendingen Verfahren und vorrichtung zur trockenen oder quasitrockenen abscheidung gasfoermiger schadstoffe aus abgasen, insbesondere rauchgasen
SE454409B (sv) * 1985-10-10 1988-05-02 Asea Stal Ab Sett vid borttagning av fororeningar fran gaser

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1330870A (en) * 1969-12-10 1973-09-19 Braxton Corp Process and apparatus for removing unwanted particles from a gas
DE3507596A1 (de) * 1985-03-04 1986-09-04 Wehrle-Werk Ag, 7830 Emmendingen Verfahren und vorrichtung zur trockenen oder quasitrockenen abscheidung gasfoermiger schadstoffe aus abgasen, insbesondere rauchgasen
SE454409B (sv) * 1985-10-10 1988-05-02 Asea Stal Ab Sett vid borttagning av fororeningar fran gaser

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DERWENT'S ABSTRACT, No. 87-312167/44, week 8744; & SU,A,1291189 (LVOV POLY), 23 February 1987 (23.02.87). *
DERWENT'S ABSTRACT, No. 90-266329/35, week 9035; & SU,A,1519761 (HALURGY RESEARCH IN), 7 November 1989 (07.11.89). *

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7150779B2 (en) 2002-04-26 2006-12-19 Board Of Regents, The University Of Texas System Modulated acoustic agglomeration system and method
WO2004041413A2 (fr) * 2002-11-01 2004-05-21 Board Of Regents Stimulation acoustique d'un systeme de diffusion de vapeur et procede associe
WO2004041413A3 (fr) * 2002-11-01 2004-07-08 Regents Board Of Stimulation acoustique d'un systeme de diffusion de vapeur et procede associe
US7238223B2 (en) 2002-11-01 2007-07-03 Board Of The Regents, The University Of Texas System Acoustical stimulation of vapor diffusion system and method
WO2015127518A1 (fr) * 2014-02-25 2015-09-03 SOVEX Em EOOD Procédé d'épuration de gaz de combustion et appareils pour sa mise en œuvre
CN107158856A (zh) * 2017-05-25 2017-09-15 华北电力大学 一种化学团聚联合声波团聚去除燃煤烟气细小颗粒物的方法
CN109126333A (zh) * 2018-09-11 2019-01-04 宁夏宝丰能源集团股份有限公司 气体净化装置
CN111036006A (zh) * 2019-12-24 2020-04-21 上海海事大学 一种声波增强的船舶废气脱硫及颗粒物去除装置

Also Published As

Publication number Publication date
SE508789C2 (sv) 1998-11-02
EP0699102A1 (fr) 1996-03-06
CA2163236A1 (fr) 1994-11-24
AU6810694A (en) 1994-12-12
SE9301713D0 (sv) 1993-05-19
SE9301713L (sv) 1994-11-20

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