NO742328L

NO742328L -

Info

Publication number: NO742328L
Application number: NO742328A
Authority: NO
Inventors: J Lawrence
Original assignee: Cluett Peabody & Co Inc
Priority date: 1973-08-31
Filing date: 1974-06-26
Publication date: 1975-03-24
Also published as: ZA743400B; RO65628A; JPS5051499A; BR7401071A; SE397820B; BE819304A; DE2431308A1; FR2242333B1; ES427679A1; GB1452161A; FI178874A; NL7408280A; SE7410855L; CA1014334A; IN142469B; FR2242333A1; DD114940A5; BG27069A3; HK31377A; IT1019147B

Description

Fremgangsmåte for fjerning av ammoniakk fra en spillgassblanding. Process for removing ammonia from a waste gas mixture.

I de senere år med utvikling av permanent press påIn recent years with the development of permanent pressure on

klær og industriell fremstillIng av tekstiler som formes til spesielle former, har det oppstått en bkende interesse for behandling av tekstiler med flytende ammoniakk.;,, Store mengder ammoniakk brukes til slike metoder og det oppstår fcJlgelig problemer med fjerning eller gjenvinning av ammoniakken. Som for-urensning er ammoniakk aggressiv i og for seg. Ammoniakk virker også som gjSdnlngsmiddel og bker algeveksten i vannleiene ub'nsket. Gjenvinning av ammoniakk fra behandlingskammere har vist seg meget kostbar. Tekstilfabrikkene har funnet gunstigere måter å investere kapital på enn i systemer for gjenvinning av clothing and the industrial production of textiles that are formed into special shapes, there has been a growing interest in treating textiles with liquid ammonia.;,, Large quantities of ammonia are used for such methods and problems naturally arise with the removal or recovery of the ammonia. As a pollutant, ammonia is aggressive in and of itself. Ammonia also acts as a fertilizer and inhibits the unwanted growth of algae in the water beds. Recovery of ammonia from treatment chambers has proven to be very expensive. The textile factories have found more favorable ways of investing capital than in systems for recycling

ammoniakk.ammonia.

I de tilfelle hvor store mengder ammoniakk benyttes kan gjenvinning gjennomfares på Skonomisk måte med gjenvizmings-utbytter^på generelt omkring 90?$. Vanligvis har gjenvinning av ammoniakkinnholdet ut over 90% vist seg for kostbar og man har kastet resten av ammoniakken. I andre tilfelle hvor det brukes mindre mengder ammoniakk og hvor ammoniakken foreligger sammen med store mengder luft, vanndamp og/elier andre bestanddeler, har gjenvinning av ammoniakk vist seg uøkonomisk. I disse tilfelle har man blitt kvitt det ammoniakkholdige avfall ved å fSre avfallet til vannveier eller til forbrenningsanlegg. In cases where large quantities of ammonia are used, recycling can be carried out in an economical way with recycling yields generally around 90?$. Usually, recovery of the ammonia content above 90% has proven too expensive and the rest of the ammonia has been thrown away. In other cases, where smaller quantities of ammonia are used and where the ammonia is present together with large quantities of air, water vapor and/or other components, recovery of ammonia has proven to be uneconomical. In these cases, the ammonia-containing waste has been disposed of by sending the waste to waterways or to incineration plants.

Det har oppstått et klart behov for fremgangsmåter for gjenvinning av ammoniakk fra avfalls-media fra ammoniakkbehandlingskammere, innenfor slike driftsmessige og okonomiske forhold som tekstilindustrien kan befatte seg,.med. A clear need has arisen for methods for the recovery of ammonia from waste media from ammonia treatment chambers, within such operational and economic conditions as the textile industry can deal with.

Man har oppdaget at det er stort behov for vandig ammoniakk i konsentrasjoner på fra 20 - 3056. Slik ammoniakk fremstilles vanligvis ved å fortynne variO^ ammoniakk med vann. Ovennevnte problemer med gjenvinning av ammoniakk fra avlc5ps-media som inneholder ammoniakk i marginale mengder lases i henhold til oppfinnelsen på en ny og særlig enkel måte. Mer spe-sielt anordnes en kjBler inneholdende et vannbad. Et kjb*lemedi-um sirkuleres i kontakt-fritt varmevekslings-forhold med vannbadet. Et vasketårn (scrubber) er anordnet over dette og i strBmningskommunlkasjon med kjBleren. Over skrubberen og i strBmningsforbindelse med denne finnes en passende luftekanal. En spillgass-stram som inneholder en blanding av ammoniakk og luft, vanndamp og/eller andre bestanddeler fSres tii kjbleren og bobler opp gjennom vannbadet slik at en del av ammoniakken absorberes fra blandingen og delvis ammoniserer vannbadet samtidig som det viderefores en delvis deammonisec^tgassblanding (ammoniakk-befridd gassblanding) opp til vasketårnet. Den delvis ammoniakk-befridde gassen vaskes med ferskvann som går ned gjennom vasketårnet slik at ferskvannet absorberes mere av ammoniakken og leverer en vesentlig deammonisert gassblanding som feires til avlopskanalen samtidig som det ammoniakkrike vann strSmmer nedover og blander seg med vannbadet. Et produkt som fortrinnsvis inneholder mellom 20 og 30 vektprosent ammoniakk i vann tappes av fra vannbadet. Oppfinnelsen karakteriseres videre ved at kjøleren og vasketårnet (skrubberen) er anordnet i et enkelt hus hvor kjøleren har en generelt horisontal avlang sylindrisk form og vasketårnet er anbragt i midten av kjølerens lengde og stikker opp fra denne. Temperaturen på vannbadet regulerer strømmen av kjølevæske som går i kontaktfri varmevekslings-sirkulasjon med vannbadet i kjøleren. Produktet re-sirkuleres til badet hvis aimnoniakk-konsentrasjonen er util-strekkelig. Man vil se at oppfinnelsen fyller et behov innen tekstilindustrien for et ammoniakkg jenvinningssystem av den Snskede type. It has been discovered that there is a great need for aqueous ammonia in concentrations of from 20 - 3056. Such ammonia is usually produced by diluting variO^ ammonia with water. The above-mentioned problems with the recovery of ammonia from avlc5ps media containing ammonia in marginal amounts are solved according to the invention in a new and particularly simple way. More specifically, a heater containing a water bath is arranged. A heating medium is circulated in contact-free heat exchange conditions with the water bath. A washing tower (scrubber) is arranged above this and in flow communication with the boiler. Above the scrubber and in direct connection with it, there is a suitable air duct. A waste gas stream containing a mixture of ammonia and air, water vapor and/or other constituents is fed into the boiler and bubbled up through the water bath so that part of the ammonia is absorbed from the mixture and partially ammoniates the water bath while at the same time passing on a partially deammonified gas mixture ( ammonia-free gas mixture) up to the washing tower. The partially ammonia-freed gas is washed with fresh water that goes down through the washing tower so that the fresh water is absorbed more by the ammonia and delivers a substantially deammonified gas mixture that is fed to the sewer at the same time that the ammonia-rich water flows down and mixes with the water bath. A product which preferably contains between 20 and 30 percent by weight of ammonia in water is drained from the water bath. The invention is further characterized in that the cooler and the washing tower (scrubber) are arranged in a single housing where the cooler has a generally horizontal elongated cylindrical shape and the washing tower is placed in the middle of the length of the cooler and protrudes from it. The temperature of the water bath regulates the flow of coolant, which runs in contact-free heat exchange circulation with the water bath in the cooler. The product is re-circulated to the bath if the ammonia concentration is insufficient. It will be seen that the invention fulfills a need within the textile industry for an ammonia recovery system of the type requested.

En hensikt med oppfinnelsen er således å tilveiebringe en fremgangsmåte og et system av den nevnte type for gjenvinning av ammoniakkholdige avløpsgasser, som er billig og virker mer effektivt enn tidligere kjente metoder. One purpose of the invention is thus to provide a method and a system of the aforementioned type for the recovery of ammonia-containing waste gases, which is cheap and works more efficiently than previously known methods.

En annen hensikt med oppfinnelsen er å eliminere Another purpose of the invention is to eliminate

ammoniakk-f orur ensning.ammonia-f orur ensation.

Ennå en hensikt med oppfinnelsen er å redusere drift-omkostningene 1 forbindelse med ammoniakkbehandlingskammere i tekstilfabrikker ved gjenvinning av et salgbart og utnyttbart produkt. Another purpose of the invention is to reduce the operating costs 1 in connection with ammonia treatment chambers in textile factories by recycling a salable and usable product.

Ennå en hensikt med oppfinnelsen er å oppnå et 20--30-prosentig ammoniakkvann som kan brukes som gjødningsmiddel, kJenjikalium for behandling av andre avløpsvann eller lignende. Another purpose of the invention is to obtain a 20--30 percent ammonia water that can be used as a fertiliser, potassium for the treatment of other waste water or the like.

Ennå et trekk ved oppfinnelsen er at det tilveiebringes et system og en fremgangsmåte av den angitte type som er enkel i drift, robust, sam kan anvendes på mange forskjellige forhold og som forøvrig fyller de oppsatte krav. Another feature of the invention is that it provides a system and a method of the specified type which is simple to operate, robust, can be used in many different situations and which otherwise fulfills the stated requirements.

Disse hensikter og trekk ved oppfinnelsen vil fremgå klarere i forbindelse med en detaljert beskrivelse av en fore-trukken utførelse av oppfinnelsen, i forbindelse med den ved-lagte tegning som viser en noe forenklet eller idealisert fremgangsmåte og instrumentering av et system som tar i bruk oppfinnelsens metode. These purposes and features of the invention will appear more clearly in connection with a detailed description of a preferred embodiment of the invention, in connection with the attached drawing which shows a somewhat simplified or idealized method and instrumentation of a system that uses the invention's method.

Som man ser av tegningen, kommer spillgass (inneholdende ammoniakk i blanding med luft, vanndamp og/eller andre stoffer) inn i systemet gjennom ledning 11, filteret 12, viften 13, vifteregulator 14 og spjeldet 15. Spillgassledningen 11 deles i to ledninger 16 og 17 for innløp i kjøleren 18. Kjøler-en 18 er delt på kjent måte 1 en rørside og en syliniderside. Rørsiden står i forbindelse med ledningene 19 og 21 for sirku-lasjon av et kjølemedium (vanligvis vann). Sylindersiden i kjøleren opptar vannbadet 22. As can be seen from the drawing, waste gas (containing ammonia mixed with air, water vapor and/or other substances) enters the system through line 11, filter 12, fan 13, fan regulator 14 and damper 15. The waste gas line 11 is divided into two lines 16 and 17 for inlet in the cooler 18. The cooler 18 is divided in a known manner into a tube side and a cylinder side. The pipe side is in connection with the lines 19 and 21 for the circulation of a cooling medium (usually water). The cylinder side in the cooler occupies the water bath 22.

Avgassen gjennom ledningene 16, 17 føres til to kammere 23i 24, respektivt (som dannes av ledeplatene 25 og 26, respek-Uvt) og fordeles langs kjøleren 18 hvorved spillgassen bobler oppover gjennom vannbadet 22 slik at en del av ammoniakken fra avgassen absorberes og delvis ammoniserer vannbadet 22. Den resulterende og delvis deammoniserte avgassen 27 går oppover til et vasketårn 28 som er anordnet over kjøleren 18 og står i forbindelse med denne. The exhaust gas through the lines 16, 17 is led to two chambers 23 and 24, respectively (which are formed by the guide plates 25 and 26, respectively-Uvt) and distributed along the cooler 18 whereby the waste gas bubbles upwards through the water bath 22 so that part of the ammonia from the exhaust gas is absorbed and partly ammonifies the water bath 22. The resulting and partially deammonified exhaust gas 27 goes upwards to a washing tower 28 which is arranged above the cooler 18 and is in connection with it.

I kjøletårnet 28 vaskes den delvis ammoniakkbefridde (deammoniserte) avløpsgassen 27 med ferskvann. Ferskvannet innføres gjennom ledning 29, regulerlngsventil 31 og en del dusjdyser 32. Forstøvningsorganer som f.eks. duken 33 er inn-satt i or å sikre at ferskvannet brytes opp .i,-jgahge små dråper 34. Dråpene 34 går ned gjennom vasketårnet 28 i direkte fysisk kratakt med den delvis ammoniakkbefridde avgassen 27 og absorberer mere av gassens ammoniakk slik at det dannes f.en i det vesentlige. ammoniakkfri gassblanding 35 som stiger opp til utløp gjennom luftekanalen 36, forsynt med spjeldet 37. Ferskvannet som er delvis ammoniakk-anriket av gassen 27 strømmer nedover og sammen med vannbadet 22 på sylindersiden av kjøleren 18. In the cooling tower 28, the partially ammonia-free (deammonised) waste gas 27 is washed with fresh water. The fresh water is introduced through line 29, control valve 31 and some shower nozzles 32. Atomizing devices such as e.g. the cloth 33 is inserted to ensure that the fresh water is broken up into small droplets 34. The droplets 34 go down through the washing tower 28 in direct physical contact with the partially ammonia-free exhaust gas 27 and absorb more of the gas's ammonia so that it forms f.en essentially. ammonia-free gas mixture 35 which rises to the outlet through the air channel 36, provided with the damper 37. The fresh water which is partially ammonia-enriched by the gas 27 flows downwards and together with the water bath 22 on the cylinder side of the cooler 18.

Et ammpniakkvann-produkt som med fordel har et ammoniakk-innhold på 20 - 30 vektprosent eller mer, tappes ut fra kjølerens sylinderside via en synkebrønn 38, ledning 39, ventil 41, pumpe 42 og ledning 43 til lagringstank 44. Sirkulasjonen av kjøle-veske gjennom ledning 19, rørsiden av kjøleren 18 og ledningen An ammonia water product, which advantageously has an ammonia content of 20 - 30 percent by weight or more, is drained from the cooler's cylinder side via a sump 38, line 39, valve 41, pump 42 and line 43 to storage tank 44. The circulation of coolant through line 19, the pipe side of the cooler 18 and the line

21 reguleres ved hjelp av reguleringsventilen 45 som igjen 21 is regulated using the control valve 45 as again

reguleres av en temperaturregulator 46. En konsentrasjonsindi-kator 47 er operativt forbundet med ledningen 41 og måler en egnet elektrisk parameter hos produktet som funksjon av ammoniakk-konsentrasjonen. Konsentrasjonsindikatoren M%©r forbundet slik at den betjener en treveisventil 48 som fører produktet enten gjennom ledning 43 til lagringstanken 44 eller gjennom ledning 49 til ledningen 11 for resirkulasjon til vannbadet 22 inntil is regulated by a temperature regulator 46. A concentration indicator 47 is operatively connected to the line 41 and measures a suitable electrical parameter of the product as a function of the ammonia concentration. The concentration indicator M% © is connected so that it operates a three-way valve 48 which leads the product either through line 43 to the storage tank 44 or through line 49 to line 11 for recirculation to the water bath 22 until

produktet når en tilstrekkelig høy ammoniakk-konsentrasjon. Tilførsel av ferskvann gjennom ledning 29 og dusjhodene 3§ reguleres av nivåreguleringsventilen 31 som igjen reguleres av nivåregulatoren 51 som er operativt forbundet med kjøleren 18. the product reaches a sufficiently high ammonia concentration. The supply of fresh water through line 29 and the shower heads 3§ is regulated by the level control valve 31 which in turn is regulated by the level regulator 51 which is operatively connected to the cooler 18.

Vasketårnet 28 og kjøleren 18 er med fordel sammen-satt i et enkelt hus eller kappe 52, ikke bare for enkelhets skyld og av Økonomiske grunner, men også f or å oppnå spesielle fordeler som vil fremgå. Kjøleren 18 har en generelt horisontal avlang sylindrisk form og vasketårnet 28 er anbragt i midten i forhold til kjølerens lengde og stikker opp. fra denne. Kjole-tårnet 28 har en generelt vertikal form og avsluttes i en Øvre ende 53 hvorpå luftekanalen eller pipen 36 kan plaseres. Brøn-nen 38 gir dybde til vannbadet 22 slik at man kan oppnå en an-riking av ammoniakkinnholdet også når ammoniakkvann tappes av gjennom ledning 39 til lagertank 43. The washing tower 28 and the cooler 18 are advantageously assembled in a single housing or casing 52, not only for the sake of simplicity and for economic reasons, but also to obtain special advantages which will appear. The cooler 18 has a generally horizontal oblong cylindrical shape and the washing tower 28 is placed in the middle in relation to the length of the cooler and sticks up. from this one. The dress tower 28 has a generally vertical shape and ends in an upper end 53 on which the air duct or pipe 36 can be placed. The well 38 provides depth to the water bath 22 so that an enrichment of the ammonia content can also be achieved when ammonia water is drained off through line 39 to storage tank 43.

For enkelhets skyld er forskjellige reguleringsorganer, sikkerhets-, låse- og andre organer ikke vist. Fagfolk på om-.rådet vil forstå at det kan foretas forskjellige avvikelser fra den viste utførelsen uten at man går utenom oppfinnelsens hoved-idé. For the sake of simplicity, various regulating, safety, locking and other means are not shown. Those skilled in the art will understand that various deviations from the embodiment shown can be made without deviating from the main idea of the invention.

Claims

1. Procedure for removing ammonia from waste gas mixtures containing ammonia mixed with air, water vapor and possibly other components, characterized by the following steps: - arrangement of a cooling zone containing a water bath, - circulation of a cooling medium in contact-free heat-exchange conditions to the water bath, - arrangement of a washing zone above and in flow connection with the cooling zone, - arrangement of ventilation ducts above and in flow communication with the washing zone, - delivery of mixtures to the cooling zone for bubbling up through the water bath so that part of the ammonia is absorbed from the mixture and partially ammonifies the water bath and delivery of a resulting partially deammonified gas mixture up to the washing zone, - arrangement of shower means in the washing zone for the introduction of fresh water which is fed down through the washing tower in direct contact with the partially deammonified gas mixture for absorption of more ammonia from this, resulting in an essentially ammonia-free gas mixture that goes up to the air channel and the resulting partially ammoniated water flows down and together with the water bath, and decanting part of the ammoniated water bath as a product.

2. Method as stated in claim 1, characterized by atomizing means in the washing zone for breaking up the fresh water flow into fine droplets.

3. Method as stated in claim 2, characterized in that the cooling zone and the washing zone are arranged in a single housing or casing•

4. Method as stated in claim 3, characterized in that the air duct forms a pipe.

5. Method as stated in claim 4, characterized by means for automatic recycling of product to the water bath until the ammonia concentration in the product is as desired.

6. Method as stated in claim 5, characterized by means for automatic regulation of the fresh water supply to the washing zone depending on the level of the water bath in the cooling zone.

7. Procedure for recovering ammonia from a waste gas mixture containing ammonia as well as air and water vapor and possibly other components, characterized by the following combination: a cooler with a cylinder side and a tube side, where the cylinder side occupies a water bath, - means for circulating a coolant on the pipe side, in contact-free heat exchange with the water bath, - a washing tower above and in flow connection with the cooler, - air duct above and in flow connection with the washing tower, - means for delivering the gas mixture to the pipe side of the cooler for bubbling up through the Water bath so that some ammonia is absorbed from the gas and partially ammonifies the water bath, and for delivering the resulting partially ammonia-free gas mixture up to the washing tower, - shower means in the washing tower for the supply of fresh water that goes down through the tower in direct contact with the partially ammonia-free gas mixture and absorbs more ammonia from this, resulting in a substantially deammonified gas landing that goes up through the air duct, and where the partially ammoniated water flows down to the water bath in the cooling zone, - as well as devices for decanting part of the ammonia water as a product.

8". System according to claim 7, characterized in that the cooler and the washing tower are formed by a single surrounding jacket.

9. System as stated in claim 8, additional performance data - the cooler has a generally horizontal elongated cylindrical shape, - the washing tower is arranged in the middle in relation to the cooler's length and extending upwards from the cooler, - the washing tower is arranged vertically and finished at the upper end, - the air duct is connected to the upper end of the washing tower.

10. System as stated in claim 9, characterized by atomizing means in the washing tower for dividing the fresh water flow into fine droplets.

11. System as stated in claim 10, character! sert in that the air duct is designed as a pipe.

12. System according to claim 11, characterized by means for automatic recycling of the product to the water bath until the ammonia concentration in the product reaches the desired height.

13. System as stated in claim 12, characterized by means for automatic regulation of the fresh water supply to the washing tower to maintain a desired level for the water bath.