DK142624B - Process for producing a methane-rich gas. - Google Patents
Process for producing a methane-rich gas. Download PDFInfo
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- DK142624B DK142624B DK162178AA DK162178A DK142624B DK 142624 B DK142624 B DK 142624B DK 162178A A DK162178A A DK 162178AA DK 162178 A DK162178 A DK 162178A DK 142624 B DK142624 B DK 142624B
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10K—PURIFYING OR MODIFYING THE CHEMICAL COMPOSITION OF COMBUSTIBLE GASES CONTAINING CARBON MONOXIDE
- C10K3/00—Modifying the chemical composition of combustible gases containing carbon monoxide to produce an improved fuel, e.g. one of different calorific value, which may be free from carbon monoxide
- C10K3/02—Modifying the chemical composition of combustible gases containing carbon monoxide to produce an improved fuel, e.g. one of different calorific value, which may be free from carbon monoxide by catalytic treatment
- C10K3/04—Modifying the chemical composition of combustible gases containing carbon monoxide to produce an improved fuel, e.g. one of different calorific value, which may be free from carbon monoxide by catalytic treatment reducing the carbon monoxide content, e.g. water-gas shift [WGS]
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C1/00—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon
- C07C1/02—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon from oxides of a carbon
- C07C1/04—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon from oxides of a carbon from carbon monoxide with hydrogen
- C07C1/06—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon from oxides of a carbon from carbon monoxide with hydrogen in the presence of organic compounds, e.g. hydrocarbons
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2523/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00
- C07C2523/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00 of the iron group metals or copper
- C07C2523/74—Iron group metals
- C07C2523/755—Nickel
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Description
(11) FREML/EGGELSESSKRIFT 142624 DANMARK «ο int.ci.» o 10 κ 3/02 (21) Ansøgning nr. 1621/78 (22) Indleveret den 1J. apr. 1978 mi (24) Løbedag 1 3 . apr. 1978 (44) Ansøgningen fremlagt og frem I æggelsesskriftet offentliggjort den 1 . d.00 . 1 980(11) FOREIGN / ANNOUNCEMENT 142624 DENMARK «ο int.ci.» o 10 κ 3/02 (21) Application No. 1621/78 (22) Filed on 1J. April 1978 mi (24) Race day 1 3. April 1978 (44) The application presented in the writ of annulment published on 1. d.00. 1 980
DIREKTORATET FORDIRECTORATE OF
PATENT- OG VAREMÆRKEVÆSENET <30) Woritet begæret fra den (71) HALDOR TOPS/E Å/s, Nymøllevej 55» 2800 Lyngby, DK.PATENT AND TRADEMARK LABEL <30) Woritet requested from the (71) HALDOR TOPS / E Å / s, Nymøllevej 55 »2800 Lyngby, DK.
(72) Opfinder: Carsten Sejrbo Nielsen, Poppelgade 9, 1. tv., 2200 Købene havn N., DK.(72) Inventor: Carsten Sejrbo Nielsen, Poppelgade 9, 1st TV., 2200 Purchases harbor N., DK.
(74) Fuldmægtig under sagens behandling:(74) Plenipotentiary in the proceedings:
Kontor for Industriel Eneret v. Svend Schørmlng.__ (54) P^emgangsraåde til fremstilling af en metanrig gas.Office of Industrial Energetic v. Svend Schørmlng .__ (54) Procedures for the production of a methane-rich gas.
Den foreliggende opfindelse angår en fremgangsmåde til i mindst én adiabatisk metaniseringsreaktor at fremstille en metanrig gas ved katalytisk omdannelse af en indgangsstrøm, fremkommet ved kombinering af en forvarmet syntesegas i hovedsagen bestående af hydrogen og kulmonoxyd i rumfangsforholdet H2/CO 3:1 med en recirkulationsstrøm fra reaktoren, ved hjælp af en metaniseringskatalysator, hvis aktive komponent hovedsagelig er nikkel, og en shiftkatalysator til at shift-konvertere en del af kulmonoxydet med vanddamp i recirkulationsstrømmen, idet den kombinerede strøm føres gennem katalysatorlejet i reaktoren og en udgangsstrøm fra denne med en temperatur mellem 500 og 700°C deles i recirkulationsstrømmen, der afkøles, og en produktgasstrøm der føres bort til brug eller viderebehandling.The present invention relates to a process for producing, in at least one adiabatic methanization reactor, a methane-rich gas by catalytic conversion of an input stream, obtained by combining a preheated synthesis gas consisting essentially of hydrogen and carbon monoxide in the volume ratio H2 / CO 3: 1 with a recycle stream from the reactor, by means of a methanization catalyst whose active component is mainly nickel, and a shift catalyst to shift convert a portion of the carbon monoxide with water vapor into the recycle stream, the combined stream being passed through the catalyst bed in the reactor and an output stream thereof at a temperature between 500 and 700 ° C are divided into the recirculating stream which is cooled and a product gas stream which is diverted for use or further treatment.
I de senere år har man ofte haft en lokal og/eller periodisk mangel på naturgas. Metaniseringsprocesser har der- 2 142626 for tiltrukket sig stor opmærksomhed i forbindelse med fremstilling af metanrige gasser, som egner sig til erstatningsgas for naturgas, også betegnet syntetisk naturgas eller SNG.In recent years, there has often been a local and / or periodic shortage of natural gas. Methanisation processes have therefore attracted considerable attention in connection with the production of methane-rich gases suitable for natural gas substitute gas, also known as synthetic natural gas or SNG.
Fremstilling af erstatningsnaturgas vil normalt foregå i fire procestrin.The replacement of natural gas will normally take four steps.
Den første delproces er en trykforgasning af kulholdigt materiale, almindeligvis fast eller flydende fossilt brændstof såsom kul eller fuelolie. Ved denne proces omdannes kullet eller karbonhydriderne til kuloxyder samt mindre mængder hydrogen og metan. Trykforgasningen efterfølges som regel af en såkaldt shift-konversion. I denne proces foregår følgende såkaldte shift-reak-tion: (1) CO + H20^=i C02 + H2 ΔΗ298°Κ = ~9'9 kcal/molThe first sub process is a gasification of carbonaceous material, usually solid or liquid fossil fuel such as coal or fuel oil. In this process, the coal or hydrocarbons are converted to carbon oxides as well as smaller amounts of hydrogen and methane. The pressure gasification is usually followed by a so-called shift conversion. In this process, the following so-called shift reaction takes place: (1) CO + H2 O ^ = in CO 2 + H2 ΔΗ298 ° Κ = ~ 9'9 kcal / mol
Formålet ved shift-processen er at omdanne en del af kulmonoxydet til hydrogen. Man tilstræber altså ikke en fuldstændig omdannelse af kulmonoxydet, men som regel et forhold mellem hydrogen og kulmonoxyd i udgangsgassen fra shift-reaktoren på 3 eller lidt over 3.The purpose of the shift process is to convert part of the carbon monoxide to hydrogen. Thus, a complete conversion of the carbon monoxide is not sought, but usually a ratio of hydrogen to carbon monoxide in the exhaust gas from the shift reactor of 3 or just over 3.
Inden gassen kan underkastes metanisering må den renses idet metaniseringskatalysatoren ellers vil blive deaktiveret. Gasrensningen er normalt en vask.af gassen enten med en alkalisk vandig opløsning eller en organisk væske såsom metanol. Mange processer til gasrensning er udviklet og anvendes industrielt. Ved rensningen fjernes alt efter dens art først og fremmest kuldioxyd og svovlforbindelser, men derudover også andre sporstoffer der kan virke som katalysatorgifte. Man kan foretage gasrensningen før og/eller efter shift-konversionen, alt efter hvorledes det passer med de foreliggende driftsomstændigheder.Before the gas can be subjected to methanization, it must be purified as the methanization catalyst will otherwise be deactivated. The gas purification is usually a wash of the gas either with an alkaline aqueous solution or an organic liquid such as methanol. Many gas purification processes have been developed and used industrially. In the purification process, according to its nature, carbon dioxide and sulfur compounds are first and foremost removed, but also other trace elements which can act as catalyst poisons. You can do the gas cleaning before and / or after the shift conversion, depending on how it fits with the current operating conditions.
Metaniseringen foregår i overensstemmelse med nedenstående reaktionsligninger: (2) CO + 3 H2*=^CH4 + H20 δΗ298°κ = -49,3 kcal/mol (3) C02 +4 H2i=^CH4 + 2H20 AH2ggoK = -39,4 kcal/mol 3 142624The methanization is carried out according to the reaction equations below: (2) CO + 3 H2 * = ^ CH4 + H2O δΗ298 ° κ = -49.3 kcal / mol (3) CO2 +4 H2i = ^ CH4 + 2H20 AH2ggoK = -39.4 kcal / mol 3 142624
Dannelsen af metan, hvad enten den sker ifølge reaktion (2) eller (3) er således ledsaget af en kraftig varmeudvikling. Temperaturen af reaktanterne og produkterne vil derfor stige under passagen gennem et katalysatorleje i en adiabatisk reaktor.The formation of methane, whether according to reaction (2) or (3), is thus accompanied by strong heat generation. Therefore, the temperature of the reactants and products will rise during passage through a catalyst bed in an adiabatic reactor.
En sådan stigende temperatur vil ifølge Le Chateliers princip have tendens til at forskyde ligevægten hen imod lavere metankoncentration. Følgelig vil fuldstændig eller næsten fuldstændig konver-sion kun være mulig hvis temperaturstigningen begrænses ved at man afkøler den reagerende gas på en eller anden måde, fx ved recirkulation af afkølet produktgas.Such a rising temperature, according to Le Chatelier's principle, will tend to shift the equilibrium towards lower methane concentration. Accordingly, complete or almost complete conversion will only be possible if the rise in temperature is limited by cooling the reacting gas in some way, for example, by recirculating cooled product gas.
Fra dansk patentansøgning nr. 4956/75 kendes fremstilling af en metanrig gas i mindst én adiabatisk arbejdende metaniserings-reaktor indeholdende et leje af en metaniseringskatalysator, hvor en strøm af en forvarmet metansyntesegas indeholdende hydrogen og karbonmonoxyd kombineres med recirkulatiohssfcrøm fra metaniserings-reaktoren så de sammen føres gennem katalysatorlejet i reaktoren, mens en udgangsstrøm fra reaktoren deles i nævnte recirkulationsstrøm og en strøm af produktgas til videre behandling eller opsamling til afkøling og anvendelse. Ved denne kendte fremgangsmåde drives metaniseringsreaktoren på en sådan måde at udgangsstrømmen har en temperatur mellem 500°C og 700°C og afkøles til en temperatur mellem 250°C og 350°C, der dog samtidig er mindst-50°C over dugpunktet for udgangsstrømmen (dvs. kondénsationstemperaturen for dampen i udgangsstrømmen) ved dennes faktiske tryk og sammensætning, og recirkulationsstrømmen uddrages derpå fra udgangsstrømmen efter denne køling og kombineres uden yderligere behandling med indgangsstrømmen.Danish Patent Application No. 4956/75 discloses the preparation of a methane-rich gas in at least one adiabatic methanization reactor containing a bed of a methanization catalyst in which a stream of a pre-heated methane synthesis gas containing hydrogen and carbon monoxide is combined with recycled methane stream from recirculation stream. is passed through the catalyst bed in the reactor, while an output stream from the reactor is divided into said recycle stream and a stream of product gas for further processing or collection for cooling and use. In this known process, the methanization reactor is operated in such a way that the output stream has a temperature between 500 ° C and 700 ° C and is cooled to a temperature between 250 ° C and 350 ° C, yet at least 50 ° C above the dew point of the output stream. (i.e., the condensation temperature of the steam in the output stream) at its actual pressure and composition, and the recycle stream is then extracted from the output stream after this cooling and combined without further treatment with the input stream.
Det kritiske punkt i denne og andre adiabatiske reaktioner er recirkulationsforholdet, defineret som mængdeforholdet mellem recirkulationsstrøm og syntesegasstrøm. Alt andet lige er det ønskeligt at holde recirkulationsforholdet så lavt som muligt, idet de midler der anvendes til at drive recirkulationsstrømmen tilbage til syntesegasstrømmen, kompressorer o.l., er særdelen energikrævende, og derfor har en uheldig indvirkning på hele processens økonomi.The critical point in this and other adiabatic reactions is the recirculation ratio, defined as the ratio of recirculation flow to synthesis gas flow. All else being equal, it is desirable to keep the recirculation ratio as low as possible, since the means used to drive the recirculation stream back to the synthesis gas stream, compressors and the like are extremely energy intensive and therefore have an adverse effect on the entire economy of the process.
Det gælder, at man ved beregninger- af en metaniseringspro-ces, i hvilken en del af den afkølede udgangsstrøm recirkuleres til reaktorindgangen hvor den blandes op med syntésegåsstrømaen, kan vise at alt andet lige formindskes recirkulationsforholdet U 2624 4 når temperaturdifferencen over reaktoren, dvs. temperaturforskellen mellem indgangsstrømmen og udgangsstrømmen,øges.It is important to show that by calculating a methanization process in which a portion of the cooled output stream is recycled to the reactor input where it is mixed with the synthesis gas stream, it can be shown that all else equal the recycle ratio U 2624 4 is reached when the temperature difference across the reactor, ie. the temperature difference between the input current and the output current increases.
Por at opnå den mest økonomiske recirkulations-metaniserings-proces bør man derfor stræbe efter at få så høj en temperatur i udgangsstrømmen og så lav en temperatur i indgangsstrømmen som muligt. Praktiske, kinetiske og termodynamiske forhold sætter dog en grænse for, hvor stor en temperaturdifference man kan opnå over reaktoren.Therefore, in order to achieve the most economical recirculation methanization process, one should strive to obtain as high a temperature in the output stream and as low a temperature in the input stream as possible. However, practical, kinetic and thermodynamic conditions limit how much temperature difference can be achieved over the reactor.
Som nævnt er de to metaniseringsreaktioner meget exoterme, og ved høje temperaturer vil der derfor være tendens til sønderdeling af metan i karbonmonoxyd og hydrogen. Dette vil selvfølgelig have til resultat, at jo højere temperaturen er i udgangsstrømmen, desto mindre vil metanindholdet være når det antages at reaktionerne (2) og (3) løber til ligevægt. Det er derfor ikke hensigtsmæssigt at drive metaniseringsprocessen ved temperaturer over 700°C, som regel endda næppe over 600°C. I praksis vil det være vanskeligt at fremstille en metaniseringskatalysator der både er mekanisk stabil og har passende katalytisk aktivitet efter at have været udsat for så høj en temperatur gennem længere tid. Velegnede katalysatorer er beskrevet i DK-patentansøgningerne 2968/75 & 2388/76.As mentioned, the two methanation reactions are very exothermic, and therefore at high temperatures there will be a tendency for the decomposition of methane into carbon monoxide and hydrogen. Of course, this will result in the higher the temperature of the output stream, the less the methane content will be when it is assumed that reactions (2) and (3) run to equilibrium. Therefore, it is not appropriate to operate the methanization process at temperatures above 700 ° C, usually even barely above 600 ° C. In practice, it will be difficult to produce a methanization catalyst which is both mechanically stable and has the appropriate catalytic activity after being exposed to such a high temperature for a long time. Suitable catalysts are disclosed in DK patent applications 2968/75 & 2388/76.
Selv om dannelsen af metan termodynamisk begunstiges af lave temperaturer, sætter reaktionshastigheden dog en nedre grænse for hvor lav en temperatur i indgangsstrømmen til reaktoren det er rimeligt at have. I praksis har det vist sig at den nedre grænse dog er knyttet til katalysatorens natur. Det viser sig nemlig overraskende at nikkelkatalysatoren ødelægges, hvis indgangstemperaturen bliver for lille. Det vides ikke nøjagtigt, hvor denne grænse er, men det formodes at hvis indgangstemperaturen til reaktoren holdes under 280-300°C, så vil det i det lange løb resultere i katalysatorens ødelæggelse.However, although the formation of methane is thermodynamically favored by low temperatures, the reaction rate sets a lower limit on how low a temperature in the inlet stream to the reactor it is reasonable to have. In practice, however, the lower limit has been found to be linked to the nature of the catalyst. Surprisingly, it turns out that the nickel catalyst is destroyed if the input temperature becomes too small. It is not known exactly where this limit is, but it is believed that if the inlet temperature of the reactor is kept below 280-300 ° C, then in the long run it will result in the destruction of the catalyst.
Det er opfindelsens formål at tilvejebringe en metaniserings-proces af den indledningsvis angivne art, hvor procesøkonomien forbedres ved at recirkuleringsarbejdet nedsættes ved nedsættelse af recirkulationsforholdet. Som det vil forstås af det foregående kan dette indebære en forøgelse af forskellen mellem indgangsstrømmens og udgangsstrømmens temperatur. Det vil af det foregående også forstås at andre hensyn taler imod denne øgning af temperatur-forskellen over katalysatorelejet, idet en for høj udgangstempera-tur giver for lavt metanindhold i udgangsgassen og desuden kan 142624 5' give problemer med katalysatorens stabilitet og aktivitet» mens en for lav indgangstemperatur har tendens til at ødelægge den nikkelholdige katalysator. Det er derfor specielt opfindelsens formål at tilvejebringe en metaniseringsproces af den angivtie art, hvor recirkulationsarbejdet mindskes og nævnte temperaturforskel øges ved at temperaturen af indgangsgassen til reaktoren sænkes i forhold til hvad der ellers har været anset'for muligt.It is an object of the invention to provide a methanization process of the kind initially described, wherein the process economy is improved by reducing the recycling work by reducing the recirculation ratio. As will be understood from the foregoing, this may involve increasing the difference between the temperature of the input current and the output current. It will also be appreciated from the foregoing that other considerations contradict this increase in the temperature difference across the catalyst bed, with an excessively high starting temperature giving too low methane content in the exhaust gas and, moreover, causing problems with the stability and activity of the catalyst. too low an input temperature tends to destroy the nickel-containing catalyst. It is therefore the object of the invention, in particular, to provide a methanization process of the type indicated, in which the recirculation work is reduced and said temperature difference is increased by lowering the temperature of the input gas to the reactor relative to what was otherwise considered possible.
Dette opnås hvis ifølge opfindelsen nævnte kombinerede ind-gangsstrøm holdes på en temperatur mellem 175 øg 250°C og at shiftkatalysatoren er nikkel- og jernfri, er anbragt umiddelτ bart foran metaniseringskatalysatoren, regnet i indgangsstrømmens strømningsretning, og udgør mellem 10 og 75%, fortrinsvis mellem 30 og 60% af det samlede katalysatorrumfang'.This is achieved if, according to the invention, the combined input stream is maintained at a temperature between 175 ° C and 250 ° C and the shift catalyst is nickel and iron free, is located directly in front of the methanation catalyst, calculated in the flow direction of the input stream, and is between 10 and 75%, preferably between 30 and 60% of the total catalyst volume '.
Mens man ved den forannævnte kendte metanisering med recirkulation arbejder med en indgangstemperatur af gassen på over : 250°C, har det ved den foreliggende fremgangsmåde vist sig muligt at sænke denne temperatur til under denne værdi, uden at" der sker ødelæggelse af nikkelkatalysatoren.While using the aforementioned known methanization with recirculation, an operating temperature of the gas above: 250 ° C is employed, it has been found by the present process to lower this temperature below this value without destroying the nickel catalyst.
Opfindelsen skal ikke være bundet til nogen bestemt teori om grunden til at nikkelkatalysatorer til møtaniseringsreaktioner normalt deaktiveres ved indgangstemperaturer under 250-300°C, men ikke gør det under de foreliggende omstændigheder. Imidlertid kan følgende forklaring muligvis bidrage til forståelsen. Det menes at den deaktivering af nikkelkatalysatoren, der sker ved lav indgangstemperatur, skyldes dannelse af nikkelkarbonyl, Ni(C0)4, ved reaktion mellem metallisk Ni og gasformigt CO. Dette nikkelkarbonyl, som er stabilt ved det betragtede tryk ved temperaturer mindre end 290-300°C, kan således dannes ved reaktorens indgang. Ved transport med gassen til efterfølgende varmere zoner i reaktoren sker der formentlig en sønderdeling af nikkelkarbonylet og derved en aflejring af nikkel som giver anledning til krystalvækst. Hypotesen understøttes af at undersøgelser af metaniseringskatalysatoren fra et forsøg (omstående forsøg 2) viser, at der sker en transport'' af nikkel fra det øverste katalysatorlag til varmere dele af reaktoren. En kvantitativ analyse af prøver udtaget fra de øversté 30 cm af katalysatoren viste et relativt fald i nikkelindhold mellem 0 og 5%. En tilsvarende analyse på prøver udtaget 50-60 cm fra katalysatorlagets top viste en relativ stigning i nikkelindholdet mellem 2 og 4%. Idet tendensen til nikkelkarbonyldannelse U2624 6 ud over tryk og temperatur må være afhængig af den koncentration af CO, som foreligger i gassen, tænkes den foreliggende fremgangsmåde at virke som følger: Den CO-rige gas bliver ved en lav temperatur, hvor der vil ske karbonyldannelse over en nikkelkatalysator, først ført gennem en shiftkatalysator hvis aktive metaller ikke danner karbonylforbindelser. Den svagt exoterme shiftproces vil opvarme gassen en smule samt delvis omdanne karbonmonoxyd.The invention should not be bound by any particular theory as to the reason why nickel catalysts for counteracting reactions are normally deactivated at input temperatures below 250-300 ° C, but do not in the present circumstances. However, the following explanation may contribute to the understanding. It is believed that the deactivation of the nickel catalyst that occurs at low input temperature is due to the formation of nickel carbonyl, Ni (CO) 4, by reaction of metallic Ni with gaseous CO. Thus, this nickel carbonyl, which is stable at the considered pressure at temperatures less than 290-300 ° C, can be formed at the inlet of the reactor. When transported with the gas to subsequent warmer zones in the reactor, there is probably a decomposition of the nickel carbonyl and thereby a deposition of nickel which gives rise to crystal growth. The hypothesis is supported by studies of the methanization catalyst from one experiment (inverse experiment 2) showing that there is a transport of nickel from the upper catalyst layer to warmer portions of the reactor. A quantitative analysis of samples taken from the top 30 cm of the catalyst showed a relative decrease in nickel content between 0 and 5%. A similar analysis on samples taken 50-60 cm from the top of the catalyst layer showed a relative increase in nickel content between 2 and 4%. Since the tendency for nickel carbonyl formation U2624 6 to depend on pressure and temperature depends on the concentration of CO present in the gas, the present process is thought to work as follows: The CO-rich gas stays at a low temperature where carbonyl formation over a nickel catalyst, first passed through a shift catalyst whose active metals do not form carbonyl compounds. The slightly exothermic shift process will slightly heat the gas as well as partially convert carbon monoxide.
Når gassen herefter ledes over metaniseringskatalysatoren er tendensen til nikkelkarbonyldannelse på grund af den svage temperaturstigning og lavere CO-’indhold i det væsentlige fjernet.When the gas is then passed over the methanization catalyst, the tendency for nickel carbonyl formation due to the low temperature rise and lower CO₂ content is substantially removed.
Det er mest hensigtsmæssigt at shiftkatalysatoren og metaniseringskatalysatoren befinder sig i samme reaktor og således at førstnævnte - ved anvendelse af strømningsretning med nedadgående gasstrøm, hvad der vil være det normale -danner et lag umiddelbart oven på sidstnævnte. Det giver den sim-pleste apparatopbygning og sikrer det mest muligt intime samvirke mellem de to katalysatorer på den beskrevne måde.It is most convenient for the shift catalyst and the methanation catalyst to be in the same reactor and so that the former - using downstream gas flow direction, which would be the normal - forms a layer immediately on top of the latter. It provides the simplest device design and ensures the most intimate interaction between the two catalysts in the manner described.
Imidlertid kan der i nogle tilfælde være tale om ombygning af et eksisterende metaniseringsanlæg hvor der allerede forefindes en metaniseringsreaktor, og en sådan vil som regel blot have den størrelse som behøves for et anlæg af den givne størrelse. I så fald kan det ifølge opfindelsen være hensigtsmæssigt at de to katalysatorer er anbragt i hver sin reaktor, der tilsammen virker som et adiabatisk arbejdende reaktorkompleks, idet reaktoren med shiftkatalysatoren befinder sig umiddelbart foran reaktoren med metaniseringskatalysatoren, regnet i den kombinerede indgangsstrøms strømningsretning.However, in some cases it may be a rebuild of an existing methanisation plant where a methanisation reactor already exists, and such will usually only have the size needed for a given size plant. In this case, it may be convenient for the invention to have the two catalysts disposed in their respective reactors, which together act as an adiabatic working reactor complex, the reactor with the shift catalyst located directly in front of the reactor with the methanization catalyst, calculated in the combined flow stream direction.
Som metaniseringskatalysator kan anvendes enhver kendt me-taniseringskatalysator der indeholder nikkel. Nikkelet vil som regel være på en haar er. Denne kan bestå af konventionelle materialer såsom aluminiumoxyd, siliciumdioxyd, magniumspinel eller blandinger deraf. Særlig fordelagtigt er det hvis bæreren delvis består af zirkoniumoxyd som beskrevet i forannævnte DK-patentan-søgning nr. 2968/75. Nikkelet kan med særlig fordel være promo-teret med molybdæn som beskrevet i DK-patentansøgning nr. 2388/76. Eventuelt kan en del af nikkelet være erstattet med kobolt. Det er dog ikke væsentligt for den gode virkning af fremgangsmåden ifølge opfindelsen om den anvendes med den ene eller anden nik-kelholdige katalysator.Any known methanation catalyst containing nickel can be used as a methanization catalyst. The nickel will usually be on a hair's. This may consist of conventional materials such as alumina, silica, magnesium spinel or mixtures thereof. It is particularly advantageous if the carrier is partially made of zirconia as described in the aforementioned DK patent application 2968/75. The nickel may be particularly advantageously promoted with molybdenum as described in DK Patent Application No. 2388/76. Optionally, part of the nickel may be replaced by cobalt. However, it is not essential for the good effect of the process according to the invention if used with some nickel-containing catalyst.
Shift-katalysatoren kan ligeledes være en konventionel 7 142624 shiftkatalysator. Sådanne Indeholder normalt mindst to af metallerne Cu, Zn og Cr, eventuelt 1 form af oxyder og eventuelt på en bærer. Det er uden betydning for den gunstige virkning af den foreliggende fromgangsmåde, hvilken shift-katalysator den indeholder, blot shift-katalysatoren ikke indeholder metaller der danner metalkarbonyler.The shift catalyst may also be a conventional shift catalyst. Such usually contain at least two of the metals Cu, Zn and Cr, optionally 1 form of oxides and optionally on a support. The shift catalyst it contains is of no importance to the beneficial effect of the present process, provided that the shift catalyst does not contain metals forming metal carbonyls.
Det skal nævnes at det i og for sig er kendt at anbringe en shiftkatalysator og en metaniseringskatalysator i samme reaktor, fe fra tysk offentliggørelsesskrift nr. 2432887. Det beskriver en fremgangsmåde til fremstilling af en metanrig naturgas-erstatningsgas ud fra en af kul, tjære eller residualolier ved forgasning frembragt rågas, idet man efter rensning og udvaskning til et indhold af COj på under 2% indstiller den vaskede gas på et rumfangsforhold vanddamp: kulmonoxyd på 0,55:1 til 1:1 og fører denne gas ved en indgangstemperatur på 300-500°C gennem en reaktionszone som indeholder en shift-katalysator og en metaniseringskatalysator i rumfangsforholdet ca. 1:4 til 1:10. 'It should be mentioned that it is known per se to place a shift catalyst and a methanization catalyst in the same reactor, German Patent Publication No. 2432887. It describes a process for producing a methane-rich natural gas substitute gas from a coal, tar or Residual oils by gasification produced crude gas, after purification and leaching to a content of CO 2 of less than 2% the vaporized gas was adjusted to a volume ratio of water vapor: carbon monoxide of 0.55: 1 to 1: 1 and conducted this gas at an inlet temperature of 300 -500 ° C through a reaction zone containing a shift catalyst and a methanization catalyst in the volume ratio of approx. 1: 4 to 1:10. '
Det der sker ved den kendte fremganggmåde er således noget ; andet end der sker ved den foreliggende fremgangsmåde, nemlig at-man forlægger shift-reaktionen og metaniseringsreaktionen til samme reaktor, og man opnår i det væsentlige at spare plads, specielt at nedsætte selve reaktorrumfangene, samtidig med at man udnytter det vand der dannes ved metaniseringsreaktionen (se foranstående reaktionsligninger (2) og (3)) scan råmateriale i shiftreaktionen (ligning (1)).Thus, what happens in the known method is something; other than by the present process, namely, placing the shift reaction and the methanation reaction to the same reactor, and substantially saving space, in particular reducing the reactor volumes themselves, while utilizing the water generated by the methanation reaction. (see preceding reaction equations (2) and (3)) scan raw material in the shift reaction (equation (1)).
Derimod opnår man ikke ved den kendte fremgangsmåde at nedsætte indgangstemperaturen til metaniseringsreaktoren, og recirkulationsforholdet skal derfor være højt. Det skal fremhæves åt man ved den foreliggende fremgangsmåde ikke undgår en shift-reaktor, hvis fremgangsmåden indgår som led i en proces til fremstilling af SNG ved forgasning af kul, tjære eller tung olie, rensning, shift-reaktion og metanlsering, idet udgangsmaterialet for den forelig- ' gende fremgangsmåde jo er en gas der indeholder hydrogen og kulmonoxyd i hovedsagen i forholdet 3:1 og fx hår været underkastet shift-reaktionen. ? I tysk offentliggørelsesskrift nr. 2432887 nævnes at man som shift-katalysator kan anvende fe en blanding af jemcxyd og krctnoxyd, og scat metaniseringskatalysator nikkel på et vandfast bæremateriale. I skriftets eksempel er der dog kun én katalysator, nemlig en metaniserings- 142624 8 katalysator af 50 vægt% nikkel på en bærer af magniumspinel, der har fungeret som både shift- og metaniseringskatalysator. Både jern og nikkel danner metalkarbonyler, men det er næppe sket i den kendte proces, eftersom temperaturen i reaktoren, selv ved indgangen har været for høj til at de foran forklarede vanskeligheder vil opstå; som nævnt fordrer skriftet en indgangstemperatur på 300-500°C; eksemplet nævner kun udgangstemperaturer, der er 460°C.By contrast, by the known method, the inlet temperature of the methanization reactor is not lowered and the recirculation ratio must therefore be high. It should be emphasized that in the present process a shift reactor is not avoided if the process is part of a process for the production of SNG by gasification of coal, tar or heavy oil, purification, shift reaction and methane leaching, the starting material for the In the present method, a gas containing hydrogen and carbon monoxide in the ratio of 3: 1 and, for example, hair, has been subjected to the shift reaction. ? German Publication No. 2432887 mentions that as a shift catalyst, a mixture of iron oxide and chlorine oxide can be used, and scat methanation catalyst nickel on a water-resistant support material. In the example, however, there is only one catalyst, namely a methanization catalyst of 50 wt% nickel on a magnesium spinel support which has acted as both shift and methanation catalyst. Both iron and nickel form metal carbonyls, but this has hardly happened in the known process since the temperature of the reactor, even at the inlet, has been too high for the difficulties explained above to occur; as mentioned, the writing requires an inlet temperature of 300-500 ° C; the example mentions only exit temperatures which are 460 ° C.
Fremgangsmåden ifølge opfindelsen skal i det følgende forklares nærmere under henvisning til tegningen, der viser et principskema for fremstilling af en metanrig gas ud fra kul, olie eller tjære ved forgasning, rensning, shift-reaktion og metanise-ring. Som det vil forstås omhandler opfindelsen kun sidstnævnte trin.The process according to the invention will be explained in more detail below with reference to the drawing, which shows a principle diagram for the preparation of a methane-rich gas from coal, oil or tar by gasification, purification, shift reaction and methanisation. As will be understood, the invention relates only to the latter step.
Råmateriale såsom kul eller en tung oliefraktion, fx en tung residualolie eller fuelolie, føres gennem en ledning eller andet tilførselsorgan til en forgasningszone 12, hvor råmaterialet under højt tryk forgasses. Den dannede gas føres gennem en ledning 13 til et rensetrin 14, derfra gennem en ledning 15 til en shiftreaktor 16 og fra denne gennem en ledning 17 til en vaskezone 18. I vaskezonerne 14 og 18 sker der fjernelse af katalysatorgifte m.m. og udvaskning af kuldioxyd; den ene af dem, fortrinsvis zonen 14, kan eventuelt udelades. Fra vaskezonen 18 går gassen ind i en ledning 19 med et rumfangsforhold mellem Hg og CO på i det væsentlige 3:1; gassen her kan indeholde vekslende mængde vanddamp og ganske små mængder kuldioxyd og metan. Gassen føres gennem ledningen 19 til en metaniseringsreaktor 20 med en indgangstemperatur her på 175-250°C. Metaniseringsreaktoren er af i og for sig konventionel type, men mens en metaniseringsreaktor ved konventionelle metaniseringsreaktioner kun indeholder en metaniseringskatalysator, normalt med nikkel som hovedkomponent i det katalytisk aktive materiale, så indeholder den foreliggende reaktor nederst et lag 22 med en metaniseringskatalysator og umiddelbart oven på dette et lag 21 med en shift-katalysator. Det forudsættes herved at gasstrømmens retning som vist med pile er oppefra nedefter; hvis strømningsretningen er den modsatte, skal de to katalysatorers placering ombyttes, idet shift-katalysatoren skal være ved reaktorens indgang. De to katalysatorer skilles af et grænselag 23. Dette kan eventuelt, men behøver ikke at være apparatmæs- 9 142624 sigt markeret, fx ved hjælp af et trådnet. Qassen forlader meta-niseringsreqdctoren 20 gennem en udgangsiednipg 24 med en tempera^ tur mellem 500 og 700°C, fortrinsvis højst <S00°C. Den afkøles i et køleorgan 25 og deles herefter i to strømroe, en udgangsstrøm 26 der føres bort til videre behandling eller brug, og en recirkulationsstrøm 27 der føres tilbage til in£gangslednirtgen IS, hvor den blandes med frisk syntesegas fra shiftrqaktpren 16 og vasketrii)-net 18. Som forklaret foran skal recirkulat^onsstrømmen være så lille som muligt og indgangstemperaturen af den af recirkulationsstrømmen og strømmen af den friske syntesegas kombinerede indgangsstrøm i ledningen 19 være så lav som muligt inden for de angivne grænser; som også forklaret hænger disse to parametre sammen.Raw material such as coal or a heavy oil fraction, e.g., a heavy residual oil or fuel oil, is passed through a conduit or other feed means to a gasification zone 12 where the raw material is gasified under high pressure. The gas formed is passed through a conduit 13 to a purification stage 14, thence through a conduit 15 to a shift reactor 16 and thence through a conduit 17 to a washing zone 18. In the washing zones 14 and 18, catalyst poisoning and the like are removed. and leaching of carbon dioxide; one of them, preferably zone 14, may optionally be omitted. From the wash zone 18, the gas enters a conduit 19 with a volume ratio of Hg to CO of substantially 3: 1; the gas here may contain alternating amounts of water vapor and very small amounts of carbon dioxide and methane. The gas is passed through conduit 19 to a methanization reactor 20 having an inlet temperature here of 175-250 ° C. The methanization reactor is of a conventional type per se, but while in conventional methanization reactions a methanization reactor contains only one methanization catalyst, usually with nickel as the main component of the catalytically active material, the present reactor contains at the bottom a layer 22 with a methanization catalyst and immediately on top of it. a layer 21 with a shift catalyst. It is hereby assumed that the direction of the gas flow as shown by arrows is from top to bottom; if the flow direction is the opposite, the location of the two catalysts must be changed, the shift catalyst having to be at the reactor entrance. The two catalysts are separated by a boundary layer 23. This may or may not be marked in terms of apparatus, for example by means of a wire mesh. The cassette leaves the metization reactor 20 through an output nip 24 with a temperature between 500 and 700 ° C, preferably at most <S00 ° C. It is cooled in a cooling means 25 and then divided into two streams, an output stream 26 which is passed on for further processing or use, and a recirculation stream 27 which is returned to the inlet joint IS, where it is mixed with fresh synthesis gas from the shaker 16 and washing stream). 18. As explained above, the recirculation flow must be as small as possible and the inlet temperature of the recirculation stream and the flow of the fresh synthesis gas inlet conduit 19 must be as low as possible within the specified limits; as also explained, these two parameters are related.
Fremgangsmåden ifølge opfindelsen skal yderligere belyses ved et forsøg (i det følgende betegnet forsøg nr. 3), der er sammenlignet med to sammenligningsforsøg (1 og‘2). Afle tre forsøg udførtes som langtidsforsøg i et pilotanlæg der; kun omfattede en metaniseringsreaktor af i princippet samme art som reaktoren 20 på tegningen, samt refurfedninger etc. Der blev således ikke foretaget forgasning, rensning og shift-konvertering. Den benyttede reaktor var desuden af hensyn til at der var tale om fprsøg udstyret med en termolomme placeret kongruent med reaktoren i denries akse. Termolommen, der er indført i bunden af reaktoren, løber langs aksen helt op til reaktorens top. I en sådan tpfmolonaje kan man placere ternjometre og således bestemme temperatupprofilen i reaktoren.The method according to the invention is further elucidated by an experiment (hereinafter referred to as experiment # 3), which is compared with two comparative experiments (1 and 2). Three trials were conducted as long-term trials in a pilot plant there; only included a methanization reactor of basically the same kind as the reactor 20 in the drawing, as well as refurements, etc. No gasification, purification and shift conversion were thus carried out. The reactor used was, moreover, for the purpose of the probe being equipped with a thermocouple located congruent with the reactor in the denries axis. The thermocouple inserted at the bottom of the reactor runs along the axis all the way to the top of the reactor. In such tpmolonaje, ternometers can be placed and thus determine the temperature profile in the reactor.
Reaktorens dimensioner var:The reactor dimensions were:
Materiale AISX 316* Længde 2800 mmMaterial AISX 316 * Length 2800 mm
Indre diameter 50 isnInner diameter 50 isn
Ydre diameter 63 mmOuter diameter 63 mm
Termolommens ydre diameter · 8 mro 2Thermal pocket outer diameter · 8 mro 2
Frit tværsnitsareal 191Q mm x Standard-stållegering ifølge American Iron and Steel Institute indeholdende bl.a. krom, nikkel og molybdæn.Free cross-sectional area 191Q mm x Standard steel alloy according to the American Iron and Steel Institute containing, inter alia, chrome, nickel and molybdenum.
10 14262410 142624
Reaktoren blev under alle tre forsøg drevet adiabatisk, dvs. uden varmeveksling med omgivelserne. Ud over isolering var reaktoren omviklet med et elektrisk varmelegeme, ved hvis hjælp der blev kompenseret for det varmetab, som det er umuligt at undgå i praksis.The reactor was operated adiabatically in all three experiments, ie. without heat exchange with the surroundings. In addition to insulation, the reactor was wrapped with an electric heater, with the help of which was compensated for the heat loss which is impossible to avoid in practice.
Ialt tre forskellige katalysatorer blev brugt under forsøgene.A total of three different catalysts were used during the experiments.
Til metanisering blev brugt to forskellige katalysatorer betegnet Ml og M2. Begge katalysatorer er konventionelle nikkelkatalysatorer med .25% W/W nikkel på en keramisk bærer. M2 adskiller sig kun fra Ml ved at indeholde 2% W/W molybdæn. Indholdet af molybdæn i katalysatoren M2 indvirker ikke på forsøgsresultaterne og har ingen betydning for opfindelsen. Denne er som nævnt ikke knyttet til brugen af en bestemt slags metaniserings- eller shift-katalysator, blot førstnævnte indeholder nikkel og sidstnævnte ikke gør det.For methanization, two different catalysts designated M1 and M2 were used. Both catalysts are conventional nickel catalysts with .25% W / W nickel on a ceramic support. M2 differs from Ml only by containing 2% W / W molybdenum. The content of molybdenum in the catalyst M2 does not affect the test results and has no bearing on the invention. As mentioned, it is not linked to the use of a particular type of methanization or shift catalyst, only the former contains nickel and the latter does not.
Den benyttede shiftkatalysator. S, var en konventionel Cu-Zn-Cr katalysator.The shift catalyst used. S, was a conventional Cu-Zn-Cr catalyst.
Syntesestrømmen blev af praktiske grunde fremstillet ved krakning af metanol over en katalysator efterfulgt af tilsætning af brint til et brint-karbonmonoxydforhold på 3.The synthesis stream was prepared for practical reasons by cracking methanol over a catalyst followed by the addition of hydrogen to a hydrogen-carbon monoxide ratio of 3.
I modsætning til hvad man vil gøre ved normal drift blev recirkulationsstrømmen af praktiske grunde drevet tilbage til syntes egas strømmen af en kompressor, beregnet til at arbejde ved temperaturer under ca. 100°C. Af denne grund afkøledes udgangsstrømmen fra reaktoren til under 100°C i modsætning til hvad man vil gøre ved normal drift, hvorved al vanddampen kondenseredes ud.Contrary to what one would do in normal operation, the recirculation flow was, for practical reasons, driven back to the egas flow by a compressor, designed to operate at temperatures below approx. 100 ° C. For this reason, the output stream from the reactor was cooled to below 100 ° C as opposed to what would be done in normal operation, thereby condensing out all the water vapor.
Efter fraskillelse af vandet deltes den tørre udgangsstrøm i en recirkulationsstrøm og en produktstrøm, hvorefter der foretoges opvarmning til den ønskede temperatur. Til recirkulationsstrømmen sattes efter kompressionen den beregnede mængde vand, den ville have indeholdt, hvis det ikke havde været nødvendigt at fjerne dette inden kompressionen. En vandmængde svarende til forskellen mellen udkondenseret vand og vand tilsat recirkulationsstrømmen tænkes tilsat produktstrømmen. På denne måde simuleredes de virkelige driftsforhold som ville have hersket, hvis der ikke havde været anvendt en kompressor som nævnt.After separating the water, the dry starting stream is divided into a recycle stream and a product stream, after which heating to the desired temperature is carried out. To the recycle stream, after compression, the calculated amount of water it would have contained had it not been necessary to remove it prior to compression was added. An amount of water corresponding to the difference between condensed water and water added to the recycle stream is thought to be added to the product stream. In this way, the real operating conditions that would have prevailed if a compressor had not been used as mentioned above were simulated.
Tabel 1 viser driftsparametre for de tre forsøg. Forsøgene var, som det ses af tabellen, meget langvarige. Over så lange 11 142624 tidsrum er det ikke muligt at holde de enkelte temperaturer, gasstrømmenes sammensætning og volumenhastighed samt tryk helt konstante. Små svingninger omkring de tilstræbte værdier i tidjen kan ikke undgås. Med jævne mellemrum blev der derfor i hvert forsøg foretaget målinger af de forskellige temperaturer, tryk og gasstrømmenes volumenhastighed. Gasstrømmene blev ligeledes analyse- ret og deres indhold af forskellige komponenter bestemt. Det er således tre sådanne målinger, der er angivet i Tabel 1. De enkelte målinger er udvalgt fordi de skønnes at repræsentere et gennemsnit af målinger foretaget i løbet af hvert forsøg.Table 1 shows operating parameters for the three experiments. The experiments, as seen in the table, were very lengthy. Over such a long period of time, it is not possible to keep the individual temperatures, the composition and volume of the gas streams as well as the pressure constant. Small oscillations around the desired values in the thigh cannot be avoided. Therefore, at regular intervals, measurements of the various temperatures, pressures and gas flow volume velocities were made in each experiment. The gas streams were also analyzed and their contents of various components determined. Thus, there are three such measurements listed in Table 1. The individual measurements are selected because they are estimated to represent an average of measurements taken during each trial.
Det ses af tabellen, at sammensætningerne af recirkulationsstrømmen og produktstrømmen ikke er ens, som de teoretisk skulle være. Det skyldes dels måleusikkerhed, dels at det ikke er muligt helt nøjagtigt at beregne hvor meget vanddamp man ved simulationen skal tilsætte recirkulationsstrømraen efter kompressionen.It can be seen from the table that the compositions of the recycle stream and the product stream are not the same as they should theoretically be. This is partly due to measurement uncertainty and partly that it is not possible to calculate exactly how much water vapor is to be added in the simulation after compression in the simulation.
Den i forsøg nr. 1 anvendte katalysator var Ml. Mængden af katalysator i reaktoren var 3,3 liter svarende til at 1730 mm af reaktoren var fyldt op med Ml. Forsøget kunne gennemføres i den , viste lange tid stort set uden ændringer.The catalyst used in experiment # 1 was Ml. The amount of catalyst in the reactor was 3.3 liters, corresponding to 1730 mm of the reactor being filled with Ml. The experiment could be conducted in it, shown for a long time virtually without change.
I forsøg nr. 2 blev benyttet en kombination af de to metani-seringskatalysatorer. Ialt blev der brugt 1,15 liter Ml og 2,16 liter M2. Katalysatorerne var fordelt således, at regnet fra indgangen til reaktoren var de første 500 mm Ml, de næste 1130 mm M2 og de sidste 100 mm igen Ml.In experiment # 2, a combination of the two methanation catalysts was used. A total of 1.15 liters of Ml and 2.16 liters of M2 were used. The catalysts were distributed such that from the entrance to the reactor the first 500 mm ml, the next 1130 mm m2 and the last 100 mm again were ml.
I forsøg nr. 3 blev benyttet en kombination af shiftkataly-: satoren S og M2. De anvendte mængder af katalysator var henholdsvis 0,95 liter og 2,85 liter. Placeringen i reaktoren var fra indgangen at regne således, at de første 500 mm var S og de efterfølgende 1500 mm var M2. Forholdet mellem shift- og metaniseringska-talysator var som følge heraf 1:3 på volumenbasis. Beregnet på vægtbasis er forholdet 1:3,5, idet en liter af hver katalysator vejer henholdsvis 1040 g og 1228 g i reduceret tilstand.In experiment # 3, a combination of the shift catalyst S and M2 was used. The amounts of catalyst used were 0.95 liters and 2.85 liters, respectively. The position in the reactor was calculated from the entrance so that the first 500 mm was S and the subsequent 1500 mm was M2. As a result, the ratio of shift to methanation catalyst was 1: 3 on a volume basis. Calculated on a weight basis, the ratio is 1: 3.5, with one liter of each catalyst weighing 1040 g and 1228 g in reduced state, respectively.
Under forsøg nr. 2 observeredes det, at deaktiveringen af metaniseringskatalysatoren begyndte i træflaget mellem indgangsgassen til reaktoren og katalysatoren og med tiden bredte sig ned gennem katalysatorlaget.During experiment # 2, it was observed that the deactivation of the methanization catalyst began in the wood flake between the input gas to the reactor and the catalyst and, over time, spread through the catalyst layer.
Grunden til at deaktiveringen af metaniseringskatalysatoren ikke giver sig udslag i formindsket metanindhold i produktstrømmen, er at reaktoren indeholder metaniseringskatalysator i overskud.The reason that the deactivation of the methanization catalyst is not reflected in reduced methane content in the product stream is that the reactor contains methanization catalyst in excess.
12 14262412 142624
Dette medførte at mængden af aktiv katalysator hele tiden var så stor, at metaniseringsreaktionerne (2) og (3) kunne nå at løbe til ligevægt.As a result, the amount of active catalyst was constantly so high that the methanation reactions (2) and (3) could reach equilibrium.
Som mål for deaktiveringen af katalysatoren ved forsøgets afslutning benyttedes middeldiameteren af katalysatorens nikkelkrystaller, idet en krystalvækst i disse forsøg kan tages som udtryk for deaktivering.As a measure of the deactivation of the catalyst at the end of the experiment, the average diameter of the catalyst nickel crystals was used, as crystal growth in these experiments can be taken as an expression of deactivation.
Der blev ikke observeret nogen deaktivering af katalysatoren under forsøg nr. 1 udover hvad der normalt forekommer. Ved åbning af reaktoren efter afslutning af forsøget observeredes at katalysatoren syntes at være i god stand. En nærmere undersøgelse af det øverste 50 cm store lag afslørede, at den gennemsnitlige nikkelkrystaldiameter var 200 Å. Nikkelkrystaldiameteren i den ubrugte katalysator varierer mellem 140 og 180 Å.No deactivation of the catalyst was observed during Experiment # 1 beyond what normally occurs. Upon opening the reactor after completion of the experiment, it was observed that the catalyst appeared to be in good condition. Closer examination of the top 50 cm layer revealed that the average nickel crystal diameter was 200 Å. The nickel crystal diameter of the unused catalyst varies between 140 and 180 Å.
Til trods for den kortere forsøgstid blev der efter afslutning af forsøg nr. 2 konstateredes en deaktivering af katalysatoren. Ved inspektion af katalysatoren bemærkede man således en generel misfarvning samt en nedbrydning af dele af det øverste katalysatorlag. En analyse af det øverste 50 cm lange katalysatorlag viste at nikkelkrystaldiameteren varierede mellem 10.000 og 20.000 Å. .Despite the shorter test time, after the end of experiment # 2, a deactivation of the catalyst was observed. Thus, upon inspection of the catalyst, a general discoloration as well as a degradation of parts of the upper catalyst layer were noticed. An analysis of the upper 50 cm long catalyst layer showed that the nickel crystal diameter varied between 10,000 and 20,000 Å. .
Efter forsøg nr. 3 inspiceredes både shift- og metanise-ringskatalysatoren. Både shiftkatalysatoren og metaniseringskatalysatoren havde normalt udseende. En analyse af det øverste 50 cm lange lag af metaniseringskatalysatoren viste, at den gennemsnitlige nikkelkrystaldiameter var 200 Å.After Experiment # 3, both the shift and the methanation catalyst were inspected. Both the shift catalyst and the methanation catalyst had normal appearance. An analysis of the top 50 cm long layer of the methanization catalyst showed that the average nickel crystal diameter was 200 Å.
Tabel 1Table 1
Forsøg_:_.__1 _2_ 3Attempt _: _.__ 1 _2_ 3
Syntesegasstrøm, Nm3/h 12,65 13,28 12,17 % H2 74,6 73,0 72,9 % CK4 0,2.0,4 0,3 I CO 24,5 25,8 25,7 % C02 0,7 0,8 1,1Synthesis gas flow, Nm3 / h 12.65 13.28 12.17% H2 74.6 73.0 72.9% CK4 0.2.0.4 0.3 I CO 24.5 25.8 25.7% CO 2 O, 7 0.8 1.1
Indgangsstrøm, Nm3/h 50,87 49,53 38,77 % H2 35,3 33,5 36,5 % CH4 29,1 29,6 27,9 % CO 6,8 7,6 7,7 14262Λ 13Input flow, Nm3 / h 50.87 49.53 38.77% H2 35.3 33.5 36.5% CH4 29.1 29.6 27.9% CO 6.8 7.6 7.7 14262Λ 13
Tabel 1 (fortsat)Table 1 (continued)
Forsøg _1 2_ 3 % C02 2,8 3,4 2,9 % H20 26,0 25,9 25,0Test _ 1 2_ 3% CO 2 2.8 3.4 2.9% H 2 O 26.0 25.9 25.0
Recirkulationsstrøm, Nm3/h 38,22 36,25 26,6 % H2 22,1 18,7 19,1 % CH4 39,0 41,1 40,1 % CO 0,7 0,8 0,6 % C02 3,6 4,5 3,7 % H20 34,5 35,0 36,5Recycle flow, Nm3 / h 38.22 36.25 26.6% H2 22.1 18.7 19.1% CH4 39.0 41.1 40.1% CO 0.7 0.8 0.6% CO 2 3 , 4.5 4.5 3.7% H2 O 34.5 35.0 36.5
Produktstrøm, Nm3/h 7,39 7,05 6,84 % H2 22,2 19,2 19,1 % CH4 39,2 42,3 . 40,0 % CO 0,7 0,8 0,6 % C02 3,6 4,6 3,7 % H20 34,2 33,0 36,5Product flow, Nm3 / h 7.39 7.05 6.84% H2 22.2 19.2 19.1% CH4 39.2 42.3. 40.0% CO 0.7 0.8 0.6% CO2 3.6 4.6 3.7% H2 O 34.2 33.0 36.5
Katalysator Ml M1+M2 S+M2Catalyst Ml M1 + M2 S + M2
Temperaturen i indgangsstrømmen, °C 300 245 226The temperature of the input current, ° C 300 245 226
Temperaturen i udgangsstrømmen, °C 598 601 593The output current temperature, ° C 598 601 593
Tryk, kg/cm2g 30 31,2 30,5Pressure, kg / cm 2 g 31.2 30.5
Recirkulationsforhold Nm3/Nm3 3,0 2,7 2,2Recycle ratio Nm3 / Nm3 3.0 2.7 2.2
Forsøgets varighed, h 3000 1600 1175Duration of trial, h 3000 1600 1175
Tid fra forsøgets start til målingens udførelse, h_800_739 136Time from start of experiment to measurement, h_800_739 136
Af tabel 1 ses det temperaturen i indgangsgasstrømmen i forsøg 1 var 300°C og recirkulationsforholdet ca. 3. Det er ganske konventionelle parametre, og processen kan som det ses forløbe uforstyrret i meget lang tid. Ulempen herved er den indledningsvis forklarede, nemlig at et så højt recirkulationsforhold er uøkonomisk. Bestræbelsen på at nedsætte indgangstemperaturen ved at nedsætte recirkulationsforholdet noget med en konventionel metaniseringka-talysator som i forsøg 2 mislykkedes for så vidt som der skete den netop forklarede ødelæggelse af katalysatoren. Forsøget kunne med andre ord ikke have været gennemført i væsentlig længere tid således som forsøg 1 kunne. I forsøg 3 blev indgangstemperaturen 14262Λ 14 nedsat yderligere og recirkulationsforhpldet til lidt over 2, og trods dette kunne takket være shiftkatalysatorens tilstedeværelse forsøget gennemføres uden ødelæggelse af katalysatoren.From Table 1, it is seen that the temperature of the input gas stream in Experiment 1 was 300 ° C and the recirculation ratio approx. 3. These are quite conventional parameters and, as seen, the process can go undisturbed for a very long time. The disadvantage of this is initially explained, that such a high recycling ratio is uneconomical. The effort to reduce the input temperature by decreasing the recirculation ratio somewhat with a conventional methanization catalyst which in Experiment 2 failed in so far as the just explained destruction of the catalyst occurred. In other words, the experiment could not have been carried out for a significantly longer time as Experiment 1 could. In Experiment 3, the inlet temperature 14262Λ 14 was further reduced and the recirculation ratio to just over 2, and despite this, thanks to the presence of the shift catalyst, the experiment could be conducted without destroying the catalyst.
Γ forsøg nr. 3 måltes desuden temperatur og gassammensætning i overgangslaget mellem shift- og metaniseringskatalysatoren. Målingerne blev foretaget samtidig med de i tabel 1 anførte, og resultatet var som følger:Γ Experiment # 3 also measured temperature and gas composition in the transition layer between the shift and methanation catalyst. The measurements were made at the same time as those in Table 1, and the result was as follows:
T emper a tur 28 9°CTemperature 28 ° C
Gassammensætning: % H2 41,6 % CH4 27,9 % CO 2,6 % C02 8,0 % H20 19,9Gas composition:% H2 41.6% CH4 27.9% CO 2.6% CO2 8.0% H2 O 19.9
Disse tal understøtter den hypotese om virkningen af shift-katalysatoren i metaniseringsreaktoren, der er anført foran.These figures support the hypothesis on the effect of the shift catalyst in the methanization reactor listed above.
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DK162178AA DK142624B (en) | 1978-04-13 | 1978-04-13 | Process for producing a methane-rich gas. |
GB7912395A GB2018818B (en) | 1978-04-13 | 1979-04-09 | Process for preparing a methane-rich gas |
DE19792914806 DE2914806A1 (en) | 1978-04-13 | 1979-04-11 | PROCESS FOR PRODUCING A METHANE RICH GAS |
FR7909354A FR2422612A1 (en) | 1978-04-13 | 1979-04-12 | METHOD FOR PREPARING A GAS RICH IN METHANE |
JP4444079A JPS54135709A (en) | 1978-04-13 | 1979-04-13 | Manufacture of methane enriched gas |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DK162178AA DK142624B (en) | 1978-04-13 | 1978-04-13 | Process for producing a methane-rich gas. |
DK162178 | 1978-04-13 |
Publications (3)
Publication Number | Publication Date |
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DK162178A DK162178A (en) | 1979-10-14 |
DK142624B true DK142624B (en) | 1980-12-01 |
DK142624C DK142624C (en) | 1981-08-03 |
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Application Number | Title | Priority Date | Filing Date |
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DK162178AA DK142624B (en) | 1978-04-13 | 1978-04-13 | Process for producing a methane-rich gas. |
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JP (1) | JPS54135709A (en) |
DE (1) | DE2914806A1 (en) |
DK (1) | DK142624B (en) |
FR (1) | FR2422612A1 (en) |
GB (1) | GB2018818B (en) |
Families Citing this family (11)
Publication number | Priority date | Publication date | Assignee | Title |
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JPS59175442A (en) * | 1983-03-23 | 1984-10-04 | Toyo Eng Corp | Production of gas containing methane |
GB0805020D0 (en) | 2008-03-18 | 2008-04-16 | Al Chalabi Rifat | Active reformer |
WO2010078254A2 (en) | 2008-12-31 | 2010-07-08 | Shell Oil Company | Adiabatic reactor and a process and a system for producing a methane-rich gas in such adiabatic reactor |
WO2010078256A1 (en) | 2008-12-31 | 2010-07-08 | Shell Oil Company | Process for producing a methane-rich gas |
CN102482173B (en) | 2009-08-03 | 2015-04-01 | 国际壳牌研究有限公司 | Process for the production of methane |
US8461216B2 (en) | 2009-08-03 | 2013-06-11 | Shell Oil Company | Process for the co-production of superheated steam and methane |
DE102010037980A1 (en) | 2010-10-05 | 2012-04-05 | Thyssenkrupp Uhde Gmbh | Process and apparatus for producing a methane-rich gas from synthesis gas |
RU2458105C2 (en) * | 2010-11-03 | 2012-08-10 | ООО "Центр КОРТЭС" | Gas fuel preparation method |
CN102660339B (en) * | 2012-04-27 | 2014-04-30 | 阳光凯迪新能源集团有限公司 | Gas-steam efficient cogeneration process and system based on biomass gasification and methanation |
RU2697001C1 (en) * | 2015-10-16 | 2019-08-08 | Р.Е.М. Холдинг С.Р.Л. | Connecting element for connection of blade to hub of industrial axial fan and blade device containing said connecting element |
WO2023174861A1 (en) * | 2022-03-14 | 2023-09-21 | Topsoe A/S | Conversion of methanol to a hydrocarbon product stream |
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FR646782A (en) * | 1927-12-24 | 1928-11-15 | Cie Continentale Pour La Fabri | Process particularly intended for methan enrichment, or methanization of industrial gases |
DE2432887B2 (en) * | 1974-07-09 | 1980-08-28 | Metallgesellschaft Ag, 6000 Frankfurt | Process for generating a gas that is exchangeable with natural gas |
AR205595A1 (en) * | 1974-11-06 | 1976-05-14 | Haldor Topsoe As | PROCEDURE FOR PREPARING GASES RICH IN METHANE |
AT328186B (en) * | 1974-12-23 | 1976-03-10 | Vianova Kunstharz Ag | PROCESS FOR PRODUCING IMPROVED SELF-STABILIZING POLYMERIZATION DISPERSIONS IN ORGANIC LIQUIDS |
-
1978
- 1978-04-13 DK DK162178AA patent/DK142624B/en not_active IP Right Cessation
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1979
- 1979-04-09 GB GB7912395A patent/GB2018818B/en not_active Expired
- 1979-04-11 DE DE19792914806 patent/DE2914806A1/en active Granted
- 1979-04-12 FR FR7909354A patent/FR2422612A1/en active Granted
- 1979-04-13 JP JP4444079A patent/JPS54135709A/en active Granted
Also Published As
Publication number | Publication date |
---|---|
FR2422612A1 (en) | 1979-11-09 |
GB2018818B (en) | 1982-06-23 |
DK142624C (en) | 1981-08-03 |
DK162178A (en) | 1979-10-14 |
DE2914806C2 (en) | 1988-07-21 |
FR2422612B1 (en) | 1984-09-28 |
DE2914806A1 (en) | 1979-10-18 |
JPS6236503B2 (en) | 1987-08-07 |
JPS54135709A (en) | 1979-10-22 |
GB2018818A (en) | 1979-10-24 |
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