SE176069C1

SE176069C1 -

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Publication number: SE176069C1
Authority: SE
Publication date: 1961-01-01

Description

Uppfinnare: A P Bally Prioritet begard frdn den 30 juni 1959 ( Nederlanderna) Da petroleumkolvateoljor innehallande svavel krackas eller underkastas »reforming», bildas svavelvate och karbonylsulfid, som, da de krackade produkterna fraktioneras, vfisentligen kvarbliva i fraktionerna innehallande etan, etylen, propan, propylen, butan och butylen. Narvaron air dessa svavelforeningar gör de krackade produkterna illaluktande och korrosiva och ãr skadlig da de skola vidarebearbetas for erhallande av losningsmedel, säsom alkoholer. Vidare resulterar narvaron av sma mangder vatten i de krackade produkter, som redan fullstandigt befriats fran svavelvale, i bildandet genom hydrolys av koldioxid och svavelvate air karbonylsulfid, varvid svavelvatet av spar av syre oxideras till fritt svavel, som endast med stor svarighet kan avlagsnas. Inventor: AP Bally Priority requested from 30 June 1959 (Netherlands) When petroleum hydrocarbon oils containing sulfur are cracked or subjected to "reforming", hydrogen sulphide and carbonyl sulphide are formed which, when the cracked products are fractionated, essentially remain in the fractions containing ethane, propylene, ethylene, , butane and butylene. Narvaron air these sulfur compounds make the cracked products smelly and corrosive and are harmful as they must be further processed to obtain solvents, such as alcohols. Furthermore, the presence of small amounts of water in the cracked products, which have already been completely freed from sulfur whale, results in the formation by hydrolysis of carbon dioxide and hydrogen sulphide carbonyl sulphide, whereby the sulfur water is oxidized by traces of oxygen to free sulfur.

Namnda svavelforeningar forekomma aven i industrigaser, sasom vattengas, koksugnar, generatorgas och lysgas, och deras narvaro dari är lika olamplig som i de krackade produkterna. Said sulfur compounds also occur in industrial gases, such as water gases, coke ovens, generator gases and light gases, and their presence in them is as unsightly as in the cracked products.

Olika fOrmanliga forfaranden tillampas for avlagsnande av svavelvate. Sa t. ex. tvattas kolvaten med alkalimetallhydroxidlosning for avlagsnande air svavelvate. Vidare avslojas i amerikanska patentet 2 238 201 ett satt, enligt vilket flytande kolvaten innehMlande svavelvale och/eller andra sura foreningar behandlas med vattenlosliga, basiskt reagerande aminer, sasom etanolaminer, isopropanolaminer, polyetylen- oth polypropylenaminer, aminopropandioler och diaminopropanoler. Enligt brittiska patentet 631 704 kunna emellertid aminer icke anvandas med tillfredsstallande resultat i sadana fall dt kolvatena innehalla karbonylsulfid, koldisulfid och/eller aldehyder, enar dessa foreningar reagera med aminerna under hildande av stabila, neutrala kvaveforeningar, som icke ha flagon formaga att upptaga ytterligare mangder svavelvate. Vi-dare kunna de ursprungliga aminerna icke atervinnas ur reaktionsprodukten genom enkel upphettning. Enligt detta brittiska patent utgor emellertid en vattenlOsning av dietanolamin ett undantag, i det att den kan anvandas for avlfigsnande av svavelvate fran flytande kolvaten, varvid eventuellt forhandenvarande karbonylsulfid icke bindes. Dietanolaminlosningen innehallande svavelvate kan regenereras genom upphettning. Sistnamnda forfarande är emellertid behaftat med den nackdelen, att utgangsmaterial innehallande karbonylsulfid forutom svavelvate mas Le underkastas en efterbehandling fOr avagsnande av karbonylsulfiden. Enligt brittiska patentet 481 235 utfares en saclan efterbehandling air kolvaten i ett tvastegsforfarande, i vilket ett frail svavelvate redan befriat kolvate forst Ewes i beroring med en i huvudsak vattenfri alkoholisk losning av alkalimetallhydroxid, varpa det av karbonylsulfiden bildade svavelvatet avlagsnas fran det behandlade kolvatet med hj alp av en vattenlosning av alkalimetallhydroxid. En nackdel med detta forfarande är att del atgar stora mangder alkalimetaIlhydroxid, som icke kan regenereras pa enkelt satt. Various advanced procedures are applied for the removal of sulfur cotton. In e.g. the hydrocarbons are washed with alkali metal hydroxide solution to remove air sulfur water. Furthermore, U.S. Pat. However, according to British Patent 631,704, amines can not be used with satisfactory results in cases where the hydrocarbons contain carbonyl sulfide, carbon disulfide and / or aldehydes, these compounds react with the amines to form stable, neutral nitrogen compounds which have no flakes capable of taking up additional amounts. sulfur water. Furthermore, the original amines can not be recovered from the reaction product by simple heating. According to this British patent, however, an aqueous solution of diethanolamine is an exception, in that it can be used for the removal of hydrogen sulphide from the liquid hydrocarbons, whereby any carbonyl sulphide present is not bound. The diethanolamine solution containing hydrogen sulfide can be regenerated by heating. However, the latter process has the disadvantage that starting material containing carbonyl sulphide in addition to sulfuric hydrogen Le is subjected to a post-treatment to remove the carbonyl sulphide. According to British Pat. alp of an aqueous solution of alkali metal hydroxide. A disadvantage of this process is that some take up large amounts of alkali metal hydroxide, which cannot be easily regenerated.

I motsats till vad som angives i brittiska patentet 631 704 betraffande den inerta naturen air karbonylsulfid relativt en vattenlosning av dietanolamin ha senare undersokningar (brittiska patentet 803 043) visat, att det med tillampande av intensiv blandning faktiskt fir mojligt att avlagsna karbonylsulfid ur gaser och vatskor med hjalp av en vattenlosning av dietanolamin och att den resulterande anvanda dietanolaminlosningen dessutom kan regenereras. Contrary to what is stated in British patent 631 704 concerning the inert nature of air carbonyl sulphide relative to an aqueous solution of diethanolamine, recent studies (British patent 803 043) have shown that with the application of intensive mixing it is actually possible to remove carbonyl sulphide from gases and water shoes with the aid of an aqueous solution of diethanolamine and that the resulting used diethanolamine solution can also be regenerated.

I detta samband hfinvisas aven till amerikanska patentet 2 726 992, som beskriver ett satt for avlagsnande av karbonylsulfid fran 2— — normalt gasformiga petroleumkolvaten genom intensiv omroring av dessa gaser i flytande tillstand med en vattenlosning av dietanolamin. In this connection reference is also made to U.S. Pat.

Mot formodan har det nu visat sig, att anvandandet av intensiv-blandning m8jliggor eft avlagsnande av karbonylsulfid helt eller i huvudsak helt frau gaser och vatskor, som atminstone delvis aro oblandbara med vatten, med hj alp av en vattenlOsning av dipropanol&miner, och att den vid denna behandling erhallna vatskan kan pa enkelt satt regenereras. Presumably, it has now been found that the use of intensive mixing makes it possible to remove carbonyl sulphide completely or substantially completely from gases and liquids, which are at least partially immiscible with water, with the aid of an aqueous solution of dipropanol & mines, and that in The liquid obtained from this treatment can be easily regenerated.

Uppfinningen avser darfor ett salt att framstalla gaser och/eller vatskor helt eller i huvudsak belt befriade fran karbonylsulfid och vilka Mminstone delvis aro oblandbara med vatten genom behandling av gaserna och/eller vatskorna med en vattenlosning av en amin, varvid gaserna och/eller vatskorna innehallande karbonylsulfiden intensivt blandas med vattenlosningen av aminen under minst 15 sekunder vid en temperatur icke 8verstigande 70° C oth aminfasen darefter franskiljes, vilket salt kannetecknas av att den anvanda aminlosningen utgores av en vattenlosning av en eller flera dipropanolaminer. The invention therefore relates to a salt for producing gases and / or water shoes completely or substantially liberated from carbonyl sulphide and which are at least partially immiscible with water by treating the gases and / or water shoes with an aqueous solution of an amine, the gases and / or water shoes containing the carbonyl sulphide is intensively mixed with the aqueous solution of the amine for at least 15 seconds at a temperature not exceeding 70 ° C and the amine phase is then separated, which salt is characterized by the amine solution used being an aqueous solution of one or more dipropanolamines.

Vattenlosningen av en eller flera dipropanolaminer benamnes i det faljande aven »dipropanolaminfasen» eller »aminfasen». The aqueous solution of one or more dipropanolamines is hereinafter referred to as the "dipropanolamine phase" or the "amine phase".

Dipropanolaminer lampliga for anvandande enligt uppfinningen innefatta di-n-propanolamin [11N(C11.-CH2-CH2OH),] och di-isopropanolamin [HN(CH2-CHOH-C113)2] och blandningar darav. Speciellt diisopropanolamin har befunnits lamplig. Det har visat sig, att sistnamnda forening har storre absorptionsformaga med avseende pa. de sura foreningar, sasom svavelvate och koldioxid, an dietanolamin, sA att en mindre mangd absorptionsvatska erfordras. Dipropanolamines suitable for use in the invention include di-n-propanolamine [11N (C11-CH2-CH2OH),] and di-isopropanolamine [HN (CH2-CHOH-C113) 2] and mixtures thereof. Especially diisopropanolamine has been found to be suitable. It has been found that the latter association has a greater absorption capacity with respect to pa. the acidic compounds, such as hydrogen sulfide and carbon dioxide, an diethanolamine, so that a smaller amount of absorption liquid is required.

Ett praktiskt prov liar visat, att ur en viss gas 1 mol svavelvatekoldioxid kan absor- bers per 5 mol dietanolamin, medan endast 3 mol diisopropanolamin erfordrades under i ovrigt jamforbara f8rhallanden. A practical test has shown that from a certain gas 1 mole of hydrogen sulphide dioxide can be absorbed per 5 moles of diethanolamine, while only 3 moles of diisopropanolamine were required under otherwise comparable conditions.

Av ekonomiska skal aro i praktiken tekniska dipropanolaminblandningar att foredraga, sadana de erhallas exempelvis sasom biprodukt vid framstallning av dietanolamin. Dessa tekniska blandningar innehalla vanligtvis Over 90 vikts% diisopropanolamin och 10 vikts% eller mindre mono- och tripropanolaminer. Det Ar tydligt att blandningar innehallande dietanolamin avenledes kunna anvandas. Of economical purposes, technical dipropanolamine mixtures are preferred in practice, such as are obtained, for example, as a by-product in the production of diethanolamine. These technical mixtures usually contain over 90% by weight of diisopropanolamine and 10% by weight or less of mono- and tripropanolamines. It is clear that mixtures containing diethanolamine can also be used.

DA man blandar fasen innehallande karbonylsulfid med dipropanolfasen, overgar en viss mangd karbonylsulfid till den sistnamnda fasen, i vilken den formodlingen myeket snabbt hydrolyseras till svavelvate och koldioxid, vilka bindas av den basiskt reagerande aminen. Resultatet ar att mangden karbonylsulfid i dipropanolaminfasen minskas och att en ytterligare mangd karbonylsulfid aterigen kan overga till denna fas frau den behandlade fasen. Den tid, som erfordras for att karbonylsulfiden skall passera fran den ena till den andra fasen, beror vasentligen pA intensiteten I ber8ringen mellan de hada faserna. God kontakt ernas i forsta hand genom att intimt blanda de hada faserna, men mangdforhallandet mellan dessa Ar avenledes en faktor att rakna med. When the phase containing carbonyl sulphide is mixed with the dipropanol phase, a certain amount of carbonyl sulphide passes over to the latter phase, in which the formulation is very rapidly hydrolyzed to hydrogen sulphide and carbon dioxide, which are bound by the basic reacting amine. The result is that the amount of carbonyl sulfide in the dipropanolamine phase is reduced and that an additional amount of carbonyl sulfide can again be transferred to this phase from the treated phase. The time required for the carbonyl sulfide to pass from one phase to another depends essentially on the intensity of contact between the phases. Good contacts are primarily made by intimately mixing the hated phases, but the multiplicity ratio between these is a factor to be reckoned with.

Ju intensivare blandningen ar, desto kortare kan beroringstiden valj as. Med for narvarande till forfogande staende apparativ utrustning ar det emellertid praktiskt taget omojligt att minska tiden under 15 sekunder, enar delta skulle innebara ett sa stort kraftbehov for blandningen, att forfarandet skulle bliva oekonomiskt att anvandas i praktisk skala. Vid anvandande i laboratorieskala har det befunnits, att forfarandet kan genomforas pa c:a 2 sekunder i en kolloidkvarn. I detta fall uppgar emellertid den mekaniska kraft, som av omroringsorganet overfores till blandningen av de hada faserna till c:a 150 kW per m3 blandning. The more intense the mixture, the shorter the contact time can be chosen. With currently available apparatus equipment, however, it is practically impossible to reduce the time to 15 seconds, one delta would require such a large power requirement for the mixture that the process would be uneconomical to use on a practical scale. When used on a laboratory scale, it has been found that the procedure can be carried out in about 2 seconds in a colloid mill. In this case, however, the mechanical power transmitted by the agitator to the mixture of the had phases amounts to about 150 kW per m3 of mixture.

Ur teknisk och ekonomisk synpunkt erhallas vanligtvis goda resultat da blandningen ar sadan, att den av omroringsorganen till blandningen av de hada faserna overforda mekaniska energien uppgar till 0,2-1,5 kW per m3 blandning. I detta fall kommer beroringstiden vanligtvis icke att overstiga 30 minuter. DA den for behandling avsedda fasen innehaller en stor mangd karbonylsulfid, blir kontakttiden mellan de hada faserna langre och/eller maste man rOra om mera intensivt An da man renar en fas innehMlande en mindre mangd karbonylsulfid. Blandare, i vilka forfarandet lampligen kan genomforas, speciellt for be-handling av vatskor, aro propellerblandare och eentrifugalblandare, exempelvis turbomixen och Ultraturrax-mixen. For behandling av gaser anvandas foretradesvis apparater, medelst vilka gasen kan finfordelas i behandlingsvatskan. Myeket goda resultat ernas med kolonner forsedda med klockbottnar liksom kolonner med fyllkroppar, sasom Raschigringar. From a technical and economic point of view, good results are usually obtained when the mixture is such that the mechanical energy transferred by the stirring means to the mixture of the had phases amounts to 0.2-1.5 kW per m3 of mixture. In this case, the touch time will usually not exceed 30 minutes. Since the phase to be treated contains a large amount of carbonyl sulphide, the contact time between the had phases becomes longer and / or more intensive must be stirred than when a phase containing a small amount of carbonyl sulphide is purified. Mixers in which the process can be conveniently carried out, especially for the treatment of liquids, are propeller mixers and centrifugal mixers, for example the turbomix and the Ultraturrax mix. For the treatment of gases, apparatus are preferably used, by means of which the gas can be atomized in the treatment liquid. Very good results are obtained with columns fitted with bell bottoms as well as columns with filling bodies, such as Raschi rings.

Vid hehandling av gaser beror viktsforhallandet mellan dipropanolaminfasen och gasfasen i hog grad pa gasernas halt av svavelvate och karbonylsulfid. I praktiken ligger fOrhallandet i allmanhet mellan 0,1 och 20 och vanligtvis mellan 2 och 10. When handling gases, the weight ratio between the dipropanolamine phase and the gas phase depends to a large extent on the gases' content of hydrogen sulphide and carbonyl sulphide. In practice, the ratio is generally between 0.1 and 20 and usually between 2 and 10.

Det Ar fOrdelaktigt att fOra de for behandling avsedda gaserna i beroring med dipropanolaminlosningen vid forhojt tryck. I detta fall gor den mindre gasvolymen det mojligt att anvanda en kontaktapparat med mindre dimensioner. En annan f8rdel ar att Overgangen av svavelvate och karbonylsulfid till aminfasen forbattras genom Rat partialtryck hos dessa foreningar i gasen. It is advantageous to carry the gases to be treated in contact with the dipropanolamine solution at elevated pressure. In this case, the smaller gas volume makes it possible to use a contact device with smaller dimensions. Another advantage is that the transition of hydrogen sulfide and carbonyl sulfide to the amine phase is improved by Rat partial pressure of these compounds in the gas.

Vid behandling av vatskor ar det onskvart att volymforhallandet mellan dipropanolaminfas och f Or behandling avsedd vatskefas upp- — —3 gar till minst 0,1. Dessutom är syftet att tillforsakra att efter behandlingen minsta moj- liga mangd vattenlosning av dipropanolamin Or dispergerad i vatskan. FOr att erna detta bor volymforhallandet mellan dipropanol- aminfasen och den for behandling avsedda vatskan under blandningen icke understiga 0,25 och foretradesvis hallas vid c:a 0,5 enar under dessa betingelser dipropanolaminfasen är kontinuerlig och endast sin& mangder av den behandlade vatskan medtagas av dipropanolaminfasen. When treating liquids, it is desirable that the volume ratio between the dipropanolamine phase and the liquid phase intended for treatment amounts to at least 0.1. In addition, the purpose is to ensure that after the treatment the least possible amount of aqueous solution of dipropanolamine Or is dispersed in the liquid. In order to do this, the volume ratio between the dipropanolamine phase and the liquid to be treated during the mixing should not be less than 0.25 and preferably kept at about 0.5 units under these conditions. The dipropanolamine phase is continuous and only amounts of the treated liquid are taken from dipropanolamine phase.

Koncentrationen a vattenl5sningen av dipropanolamin kan variera Mom vida granser. Dipropanolaminhalten i losningen ligger i allmanhet mellan 10 och 60 vikts% och speciellt mellan 15 och 30 vikts %. Resultaten av foreliggande forfarande kunna ytterligare f6rbattras genom att fOrsatta vattenlosningen av dipropanolamin med en eller flera fOreningar, sasom trietylenglykol eller 2-metoxietanol, som framja overgangen av karbonylsulfid frau gasen eller vatskan till denna losning. The concentration of the aqueous solution of dipropanolamine can vary widely. The dipropanolamine content in the solution is generally between 10 and 60% by weight and especially between 15 and 30% by weight. The results of the present process can be further improved by providing the aqueous solution of dipropanolamine with one or more compounds, such as triethylene glycol or 2-methoxyethanol, which promote the transition of carbonyl sulfide from the gas or liquid to this solution.

Den temperatur, vid vilken forfarandet enligt uppfinningen genomfores, ligger i allmanhet Mom omradet 0-70° C och foretradesvis 15-50° C. The temperature at which the process according to the invention is carried out is generally in the range 0-70 ° C and preferably 15-50 ° C.

Da den. fran en krackningsanlaggning erhallna etan-, propan- eller butan-fraktionen behandlas enligt uppfinningen, sker detta i allm5nhet vid overatmosfariskt tryck, enar i manga fall dessa fraktioner foreligga i flytande tillstand redan i raffinaderiet och aven vidarebehandlas i detta aggregationstillstand. Da man behandlar exempelvis flytande pro-pan enligt uppfinningen, uppgar trycket vanligtvis till c:a 25 atm. abs., och dá man behandlar butan uppgar det i allmanhet till c:a 10 atm. abs. Da den. The ethane, propane or butane fraction obtained from a cracking plant is treated according to the invention, this generally takes place at superatmospheric pressure, in many cases these fractions are already in a liquid state in the refinery and are also further processed in this state of aggregation. When treating, for example, liquid propane according to the invention, the pressure usually amounts to about 25 atm. abs., and when treating butane it generally amounts to about 10 atm. abs.

Forfarandet enligt uppfinningen utfores foretradesvis i tva steg enligt motstromsprincipen. Om forfarandet genomfores i blandare och avsattningskarl, blandas den has, som innehaller karbonylsulfiden och som skall behandlas, i det forsta steget med dipropanolaminlosning, som redan delvis forbrukats. De hada faserna separeras darefter i en avsattningskammare och den has, som skall ytterligare behandlas, blandas med en ny och/eller regenererad dipropanolaminlosning for fullstandigande av behandlingen. Den i det sista steget erhallna delvis forbrukade dipropanolaminlosningen kan pa nytt blandas med obehandlad gas och/eller vatska. Forfarandet kan givetvis utforas i fler an Iva steg, i vilket fall behandlingen foretradesvis sker i motstrom i en kolonn. Da forfarandet genomfores i ett steg, foreligger det risk for att icke all karbonylsulfid skall overga till dipropanolaminfasen och for att icke alit svavelvate skall das av dipropanolaminen utan kvarbliver i eller atervander till den behandlade fasen. Da man arbetar med fler an ett steg, vidmakthallas ovannamnda betingelser med intensiv blandning, volymf5rhallande mellan de hada faserna och eventuellt tryck samt koncentration hos dipropanolaminlosningen i allmanhet I varje steg. I ett flerstegsforfarande kan det vara lampligt att anvanda en temperaturgradient, i det att temperaturen är hogst i det steg, i vilket den for behandling avsedda f asen forsta gangen blandas rued dipropanolaminl5sningen. The process according to the invention is preferably carried out in two steps according to the countercurrent principle. If the process is carried out in mixers and settling vessels, the hash containing the carbonyl sulphide to be treated is mixed in the first step with dipropanolamine solution, which has already been partially consumed. The hot phases are then separated in a deposition chamber and the hash to be further treated is mixed with a new and / or regenerated dipropanolamine solution to complete the treatment. The partially consumed dipropanolamine solution obtained in the last step can be mixed again with untreated gas and / or liquid. The process can of course be carried out in several steps, in which case the treatment preferably takes place in countercurrent in a column. As the process is carried out in one step, there is a risk that not all of the carbonyl sulphide will transfer to the dipropanolamine phase and that not all sulfur water will be taken up by the dipropanolamine but remain in or return to the treated phase. When working with more than one step, the above-mentioned conditions are maintained with intensive mixing, volume ratio between the hot phases and any pressure and concentration of the dipropanolamine solution in general in each step. In a multi-step process, it may be appropriate to use a temperature gradient, in that the temperature is highest in the step in which the phase to be treated is first mixed with the red dipropanolamine solution.

Den helt eller delvis forbrukade aminlosningen kan regenereras pa mycket enkelt satt, varpâ den pa nytt kan anvandas i processen. Regenereringen kan exempelvis ske genom upphettningen av aminlosningen till en temperatur av 70-130° C, foretradesvis 100120° C, varigenom de ur de behandlade gaserna absorberade komponenterna och/eller de bildade hydrolys-produkterna avdrivas me-deist den vattenanga, som utvecklas fran den kokande losningen. Denna behandling kan med stor fordel genomforas genom indirekt upphettning med lagtrycksanga av den f5r regenerering avsedda 15sningen, varvid absorberat svavelvate, koldioxid etc. effektivt forangas. The fully or partially consumed amine solution can be regenerated in a very simple manner, whereupon it can be reused in the process. The regeneration can take place, for example, by heating the amine solution to a temperature of 70-130 ° C, preferably 100120 ° C, whereby the components absorbed from the treated gases and / or the hydrolysis products formed are evaporated off with the water vapor which develops from the boiling solution. This treatment can with great advantage be carried out by indirect heating with low-pressure steam of the solution intended for regeneration, whereby absorbed hydrogen sulphide, carbon dioxide, etc. are effectively evaporated.

Overraskande nog har det visat sig, att vid regenereringen av en forbrukad diisopropanolaminlosning en mindre mangd vattenanga be-hover anvandas an vid regenerering av en motsvarande forbrukad dietanolaminlosning. Surprisingly, it has been found that in the regeneration of a spent diisopropanolamine solution a smaller amount of water vapor needs to be used in regenerating a corresponding spent diethanolamine solution.

Karbonylsulfid-svavelhalten i gaserna och/ eller vatskorna kan minskas till mindre an 10 % av den ursprungliga halten genom forfarandet enligt uppfinningen, i vilket fall svavelvate-halten vanligtvis uppgar till 0,005 % eller darunder. The carbonyl sulphide sulfur content of the gases and / or liquids can be reduced to less than 10% of the original content by the process of the invention, in which case the hydrogen sulphide content usually amounts to 0.005% or less.

Pa bifogade ritning askadliggores schematiskt sasom exempel ett satt, varpa en vatska innehallande karbonylsulfid kan behandlas enligt uppfinningen i ett tvastegsforfarande enligt motstromsprincipen. Den for behandling avsedda vatskan inkommer genom ledningen 1 i propeller-mixen 2, dar den omr5- res med redan delvis forbrukad dipropanolaminlosning tillford genom ledningen 3. Efter intensiv omroring avgar blandningen genom ett ror 4 till en avsattningstank 5, fran vilken den forbrukade dipropanolaminlosningen bortgar genom en ledning 6 f6r att regenereras, och den. for vidarebehandling avsedda vatskan genom ledning 7 fores till en propeller-mix 8, dar den intensivt omrores med fly eller regenererad dipropanolaminlosning till- f5rd genom en ledning 9. Blandningen fOres genom en ledning 10 till en avsattningstank 11, frail vilken den vatska, som är helt eller I huvudsak helt befriad fran karbonylsulfid och svavelvate uttages genom en ledning 12, medan den delvis fOrbrukade dipropanolamin- losningen genom ledningen 3 pumpas till propeller-mixen 2, dar den omrores med obehand- lad vatska. Da man behandlar en gas innehallande karbonylsulfid, infores den i propellermixen genom en ringformig ledning, som ar 4— — forsedd med oppningar och anordnad under propellern. I detta fall tillfores dipropanolaminlosningen pa samma satt som visat a ritningen for behandling av vatska bortsett fran att den infores vid bottnen av propeller-mixen. Behandlingen av gaser kan emellertid i allmanhet genomforas pa enkelt salt i en kolonn fOrsedd med klockbottnar. In the accompanying drawing, a set, in which a liquid containing a carbonyl sulphide liquid can be treated schematically as an example is schematically illustrated in a two-step process according to the countercurrent principle. The liquid to be treated enters through line 1 of the propeller mix 2, where it is stirred with already partially consumed dipropanolamine solution fed through line 3. After intensive stirring, the mixture exits through a tube 4 to a settling tank 5, from which the spent dipropanolamine solution is removed. through a line 6 for regeneration, and the. The liquid for further treatment through line 7 is fed to a propeller mix 8, where it is intensively stirred with escape or regenerated dipropanolamine solution supplied through line 9. The mixture is passed through a line 10 to a deposition tank 11, from which the liquid, which is completely or substantially completely freed of carbonyl sulphide and hydrogen sulphide is taken out through a line 12, while the partially consumed dipropanolamine solution is pumped through the line 3 to the propeller mix 2, where it is stirred with untreated liquid. When treating a gas containing carbonyl sulphide, it is introduced into the propeller mix through an annular conduit which is 4 - - provided with openings and arranged below the propeller. In this case, the dipropanolamine solution is fed in the same manner as shown in the drawing for the treatment of liquid except that it is introduced at the bottom of the propeller mix. However, the treatment of gases can generally be carried out on simple salt in a column provided with bell bottoms.

Uppfinningen fortydligas ytterligare genom foljande exempel. The invention is further elucidated by the following examples.

Exempel. Example.

En gas innehallande 12 volym % metan, 15 volym% etan etylen, 15 volymVo propan propylen, c:a 58 volym% irate saint 0,05 volym% svavelvate °ch. 50 dpm (delar per 1 million delar) karbonylsulfid infordes kontinuerligt av en kolonn med en diameter av 1,8 in och en langd av 12 in samt fOrsedd med 15 klockbottnar vid en temperatur av 40° C och ett tryck av 15 atm. A gas containing 12% by volume methane, 15% by volume ethane ethylene, 15% by volume propane propylene, about 58% by volume irate saint 0.05% by volume sulfur water. 50 ppm (parts per 1 million parts) of carbonyl sulphide was continuously introduced from a column with a diameter of 1.8 in and a length of 12 in and provided with 15 bell bottoms at a temperature of 40 ° C and a pressure of 15 atm.

En 10%-ig vattenlosning av teknisk diisopropanolamin. bestaende av 95 vikts % diisopropanolamin, 4 vikts % monopropanolamin och 2 vikts % tripropanolamin infordes kontinuerligt nara toppen. A 10% aqueous solution of technical diisopropanolamine. consisting of 95% by weight of diisopropanolamine, 4% by weight of monopropanolamine and 2% by weight of tripropanolamine was introduced continuously near the top.

Volymforhallandet mellan inford gas och diisopropanolaminlosning uppgick till 900:1, varjamte en total mangd om 350 ton gas och 60 ton diisopropanolaminlosning fordes genom kolonnen under 24 timmar. The volume ratio between introduced gas and diisopropanolamine solution was 900: 1, and a total of 350 tons of gas and 60 tons of diisopropanolamine solution was passed through the column for 24 hours.

Den vid toppen av kolonnen avga'ende gasen hade en svavelvatehalt av mindre in 0,0015 volym% och karbonylsulfidhalten lag under 0,5 dmp. The gas emitting at the top of the column had a sulfur water content of less than 0.0015% by volume and the carbonyl sulphide content was just under 0.5 dmp.

Detta exempel, som genomfordes i teknisk skala, visar att praktiskt taget all karbonylsulfid, namligen 99 %, och ungefar 97 % av svavelvatet avlagsnades fran gasen. This example, which was carried out on a technical scale, shows that practically all of the carbonyl sulphide, namely 99%, and about 97% of the sulfur water was removed from the gas.

Med anirandande av en vattenlosning av dietanolamin on med forhallandena i ovrigt oforandrade avlagsnades 80 % av karbonylsulfiden och 90 % av svavelvatet fran gasen. By stirring an aqueous solution of diethanolamine with the conditions otherwise unchanged, 80% of the carbonyl sulfide and 90% of the hydrogen sulfide were removed from the gas.

Den fr5n absorptionskolonnen avgaende diisopropanolaminlosningen innehallande 0,2 mol svavelvate och koldioxid per mol dlisopropanolamin infordes kontinuerligt upptill i en regenereringskolonn vid svagt overatmosfariskt tryck (0,5 atm.). Denna kolonn hade en diameter air 0,9 m och en hojd av 15 m samt inneholl 16 klockbottnar. Bottentemperaturen hölls vid 108° C genom indirekt upphettning med vattenanga. Vid denna temperatur kokar diisopropanolaminlosningen och de ur de behandlade gaserna absorberade och/ eller de bildade hydrolysprodukterna avdrivas med den frail den kokande losningen utvecklade vatten5.ngan. Med 3 kg avdrivande vattenanga per kg upptill i kolonnen avgaende gaser inneholl den fran bottnen av kolonnen avgaende diisopropanolaminlosningen 0,05 mol svavelvate och koldioxid per mol dlisopropanolamin. Denna losning aterinf6rdes i processen sedan den kylts i varmevax lare. Svavelvatekoncentrationen i den avdrivna och Iran regenereringskolonnens topp avgaende gasen Sr sa.clan att den kan vidarebehandlas utan nagon ytterligare behandling i en svavelatervinningsanlaggning. The diisopropanolamine solution from the absorption column containing 0.2 moles of hydrogen sulfide and carbon dioxide per mole of dlisopropanolamine was introduced continuously at the top of a regeneration column at slightly superatmospheric pressure (0.5 atm.). This column had a diameter of 0.9 m and a height of 15 m and contained 16 bell bottoms. The bottom temperature was maintained at 108 ° C by indirect heating with water vapor. At this temperature the diisopropanolamine solution boils and the hydrolysis products absorbed and / or the hydrolysis products formed are evaporated off with the water evolved from the boiling solution. With 3 kg of stripping water vapor per kg of gases emanating from the top of the column, the diisopropanolamine solution emanating from the bottom of the column contained 0.05 moles of hydrogen sulphide and carbon dioxide per mole of dlisopropanolamine. This solution was reintroduced into the process after it was cooled in a heat exchanger. The sulfur water concentration in the stripped gas from the stripped and Iran regeneration column Sr sa.clan that it can be further treated without any further treatment in a sulfur ether recovery plant.

Vid regenerering av en motsvarande ftirbrukad dietanolaminlOsning maste 4 kg avdrivande vattenanga anvandas per kg frail kolonntoppen avgaende gaser. When regenerating a corresponding spent diethanolamine solution, 4 kg of stripping water vapor must be used per kg of frail gases emitted from the top of the column.

Claims

Patent claim:

Introduced to produce gases and / or liquids which are wholly or substantially free of Iran carbonyl sulphide, wherein gases and / or liquids which contain carbonyl sulphide and which are at least partially immiscible with water are treated with an aqueous solution of one or more alkanolamines and the carbonyl sulphide containing the gases and / or liquids is intensively mixed with the aqueous solution for at least 15 seconds and at a temperature not exceeding 70 ° C, after which the amine phase is separated, characterized in that the carbonyl sulphide-containing gases and / or vapors are treated with an aqueous solution containing one or more flora dipropanolamines .

Salt according to claim 1, characterized in that in the treatment of gases the weight ratio of the Indian dipropanolamine phase and the gas phase is measured at 0.1: 20 during the mixing.

Salt according to patent claim 2, can be shown & ray, that the weight ratio is maintained at 2:10.

4. Salt according to patent claim 1, characterized in that in the treatment of water liquors the volume ratio between the dipropanolamine phase and the liquid phase is kept at a value not less than 0.10 during the mixing.

Salt according to claim 4, characterized in that the volume ratio is not less than 0.25.

6. sat according to patent claim 5, characterized in that the volume ratio amounts to about 0.5.

7. Salt according to any one of claims 1-6, characterized in that the mechanical energy transferred to the mixture of dipropanolamine phase and phase intended for treatment amounts to 0.2-1.5 kW per m3 volume of the mixer.

Salt according to any one of claims 7 to 7, characterized in that the intensive mixing is carried out in a propeller mix.

9. According to claim 17, characterized in that the intensive mixing is carried out in a turbo-mix.

10. A kit according to any one of claims 1-9, characterized in that the dipropanolamine content in the aqueous solution is between 10 and 60% by weight. - Salt according to claim 10, characterized in that the dipropanolamine content of the aqueous solution is between 15 and 30% by weight. 3. SUL according to any one of claims 1-11, characterized in that the aqueous solution of dipropanolamine is continued with one or more compounds which promote the transition of carbonyl sulphide from the gas and / or the liquid. 4. A claim according to claim 12, characterized in that triethylene glycol was added. Salt according to patent specification 12, Urinary characterized by the addition of 2-methoxyethanol. 6. According to one of claims 1-14, it may be noted that the treatment temperature is stated to be 15-0 G. 7. Salt according to nfi.got of claims 1-15, may be characterized in that the cracked gases are kept or transferred to a liquid state and then treated with the aqueous solution of dipropanolamine. Sift according to one of claims 1-16, characterized in that the treatment of the gas and / or the sink with aqueous solution. of dipropanolamine is carried out in more than one step according to the countercurrent principle. Silt according to claim 17, characterized in that the treatment of the gas and / or the filter is carried out in an absorption column. 10. Set according to any one of claims 1-18, characterized in that an aqueous solution of diisopropanolamine was used.

11. A kit according to any one of claims 1-18, characterized in that a technical dipropanolamine blister with a diisopropanolamine content of more than 90% by weight was used.

Gases and / or wafers wholly or substantially wholly free from carbonyl sulphide and at least partially immiscible with water, characterized in that they have been treated in any of the preceding patent claims Artford Publications: French Patent Nos. 1,192,158; U. S. A. Reissue 18 958, 2 726 992. Stoeitholin 1961. liungl. Polar. P. A. Norstedt & Soner. 510089