SE123138C1

SE123138C1 -

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Publication number: SE123138C1
Authority: SE
Publication date: 1948-01-01

Description

KLASS 5 a:41 BEVIDAT DEN 9 SEPTEMBER 1948 PATENTTID FRAN DEN. 30 JAN. 1945 PUBLICERAT DEN. 9 NOVEMBER 1948 Hdrtill en ritning. CLASS 5 a: 41 PROVIDED ON SEPTEMBER 9, 1948 PATENT PERIOD. 30 JAN. 1945 PUBLISHED IT. NOVEMBER 9, 1948 In addition to a drawing.

SVENSKA SKIFFEROLJEAKTIEBOLAGET, OREBRO. satt vid forgasning av oljeforande skifferberg in situ under tillforande av väriiie genom I skifferberget upptagna kanaler. tippfianare: F. Ljungstrom. SVENSKA SKIFFEROLJEAKTIEBOLAGET, OREBRO. sat during gasification of oil-bearing slate rock in situ during the supply of various channels taken up in the slate rock. tippfianare: F. Ljungstrom.

Uppfinningen Union sig till ett salt all framstalla skifferolja, baserat pa uppvarmning av skifferberget utan foregaende utbrytning av skiffer, -varvid de genoin uppvarmningen framkallade oljeforande gaserna avlagsnas ur henget genom i detsamma anbragta kanaler. Ur gaserna franskiljas clarpa sadana delar av desamma, vilka utgora skifferoljan, under aykylning genom kondensation. The invention refers to a salt all producing shale oil, based on heating of the shale rock without prior shale mining, in which case the oil-producing gases produced by the heating are deposited from the hanger through ducts arranged therein. From the gases clarpa separates such parts of the same, which constitute the shale oil, during cooling by condensation.

Vid uppvarmningen av ett skifferberg sker yid avgasningen av dari befintliga gasbildande substanser en borttransport av en viss materialmangd, som alltsä i gasform avgar ur berget pa liknande si.tt som t. ex. vid avgasning av stenkol eller ved, och i samtliga dessa fall kvarstar en men eller mindre ponds stomme av det ursprungliga materialet. Det kvarblivande materialet, darest det bestar ay koks eller trdkol, liar genom sin porosa struktur utomordentligt stora for gasen atkomliga ytor. Det liar nu visat sig, att aven skifferkoksen, d. v. s. i detta fall det avgasade skifferberget, har en poras struktur med mycket stora ytor, atkomliga for gaser. Samtidigt liar skidferkoksen i motsats till den vanliga koksen eller trakolet en mycket star askhalt, d. v. s. rest av icke brannbara bestandsdelar och speciellt for svenska forhallanden uppgar till omkring 70 % av den ursprungliga skiffervikten. Skifferkoksen innehaller bl. a. t. ex. olika jarnfareningar och en hel del andra bestandsdelar, som i kontakt med olika gaser dro agnade att i egenskap av katalysator paverka reaktioner i gaserna. \rid direkt avgasning av skifferberget uppstar under fortgaende framstallning ay skifferolja mycket stora volymer av uppviirmt och avgasat skifferberg bestaende huvudsakligen ay skifferkoks, som ligger kvar orubbat i sina olika lager, men som genom avgasningen blivit ombildat till en enda poras inassa framslapplig for gaser i alla riktningar. Darest salunda far varje in3 olja agar omkring 15 bergmassa, bildas t. ex. under ett ars lid vid framstallning av 20000 m skifferolja ett porost skifferberg om 300000 in'. Under sjalva fongasningsproceduren av skifferoljan anordnas mom skifferberget en langsamt framatskridande varmefront, dar saval organ for uppvarmningen (elektriska varmeelement) som avloppskanaler for gasernas avledning successivt sattas i verksamhet. When a slate rock is heated, the degassing of existing gas-forming substances takes place in the removal of a certain amount of material, which thus exits the rock in gaseous form in a similar way as e.g. in the case of degassing of coal or wood, and in all these cases a body of one or less pounds of the original material remains. The remaining material, in that it consists of coke or charcoal, due to its porous structure is extremely large for areas accessible to the gas. It has now been found that even the shale coke, i.e. in this case the degassed shale rock, has a pore structure with very large surfaces, accessible to gases. At the same time, the ski coke, in contrast to the ordinary coke or trachol, has a very strong ash content, i.e. residues of non-combustible constituents and especially for Swedish conditions amount to about 70% of the original slate weight. The slate coke contains i.a. a. e.g. various iron experiences and a lot of other constituents, which in contact with different gases were baited as catalysts to influence reactions in the gases. During the continuous production of shale rock, very large volumes of heated and degassed shale rock are formed during continuous degassing of shale rock, consisting mainly of shale coke, which remains undisturbed in its various layers, but which through the degassing has been transformed into a single pore inassable for gases in all directions. Darest salunda far each in3 oil agar about 15 rock mass, formed e.g. during a year suffering in the production of 20,000 m of shale oil a porous shale mountain of 300,000 in '. During the actual gassing procedure of the shale oil, a slowly advancing heat front is arranged in the slate rock, where both means for the heating (electric heating elements) and drainage channels for the gas diversion are gradually put into operation.

Uppfinningen avser att anvanda den pa sa satt utbildade stora porosa skifferkoksmassan sasom en katalysator far inledandet av vissa Onskade kemiska reaktioner mom densamma, alit med avsikt att framstalla olika substanser under medverkan av katalysatorn ifraga. Harvid utnyttjas de namnda gaskanalerna, sedan de slutat att tjanstgOra som avlopp for skifferoljegaserna, Liven far tillforsel av gaser till skifferberget. Samtidigt kunna andra dylika kanaler anvandas for avlopp av syntesprodukter framstallda Mom skifferberget under medverkan ay den av skifferkoksen bildade katalysatorn. En del kanaler bildar tillopp till skifferkoksen och andra hanaler avlopp fran densamma, varvid gaser, som under tryck nedforas i berget pa ett le, kunna avfonas ur detsamma pa ett annat stalle. Gaser komma harunder i kontakt med katalysatorns ytor och piiverkas av desamma pa sadant salt, som betingas av farhanden varande kemiska och fysikaliska forhallanden. The invention intends to use the large porous shale coke mass thus formed as a catalyst for initiating certain desired chemical reactions, with the intention of producing various substances with the participation of the catalyst in question. In this case, the said gas channels are used, after they have ceased to serve as a drain for the shale oil gases, Liven receives a supply of gases to the shale rock. At the same time, other such channels can be used for sewage of synthetic products produced Mom slate rock with the participation of the catalyst formed by the shale coke. Some channels form inlets to the shale coke and other channels drain from it, whereby gases which are lowered under pressure into the rock on a shelter can be removed from it in another place. Gases come into contact with the surfaces of the catalyst and are actuated by the same salt, which is conditioned by the present chemical and physical conditions.

Uppfinningen shall nedan narmare beskrivas under hanvisning till a bifogade ritning som exempel visade utforingsform for sattets genomfiirande, varvid Liven ytterligare uppfinningen kannetecknande egenskaper shola an-a bivas• Fig. 1 %Isar men eller mindre schematiskt ett skifferberg, inrattat for framstallning av skifferolja, sett i vertikalsektion. The invention will be described in more detail below with reference to the accompanying drawing as an example of the embodiment of the set, in which the further invention may be characterized by the invention. Fig. 1% Is but or less schematically a shale mountain, designed for the production of shale oil, seen in vertical section.

Fig. 2 visar ett diagram angivande temperaturfordelningen Mom skifferberget. Fig. 2 shows a diagram indicating the temperature distribution Mom slate rock.

A ritningen betecknar 10 ett natal viirmeelement, som aro anbragta pa jamna mellanrum i skifferberget 12, pa vilket är overlagrat ett lager av kalksten 14 saint eventuellt ett jordlager 16. Ett antal avgaskanaler 18 sta I forbindelse med genom kalk och skiffer ned- 2— — borrade gasavlopp 20. Varmeelementen 10 och avgaskanalerna 18 aro samtidigt anordnade i rader efter varandra i vinkel med ritningsplanet. Gasavloppen 20 tillhorande en dylik rad iiro over forbindelseror 21 och avstangnings- resp. regleringsventiler 22, 23 anslutna till en sarnlingskanal 24. En storre samlingskanal 25 for ett flertal samlingskanaler 24 forenar dessa i sin tur med en kondensor 26 och ett tvattorn 27, van skifferoljegaserna pa kant salt nedkylas och i mOjligaste man befrias fran kondenserbara oljebestandsdelar. Kondensorn 26, vilken aven kan utgoras av resp. omfatta apparatur for annan kemisk behandling av skifferoljegaser t. ex. avskiljfling av svavel eller andra biprodukter I dessa, är genom en ledning 28 ansluten till en uppsamlingsbehallare 30 for oljan. I denna behallare mynnar aven en ledning 32 fran tvatttornet 27. Fran en grenledning 34 kunna en del av de icke kondenserade gaserna avforas genom en ledning 36, i vilken ãr insatt en yentil 38, for att anvandas som bransle eller for andra andamal. En annan del av gaserna genomstromma en koinpressoranordning 40. In the drawing, 10 denotes a natural heating element, which are arranged at regular intervals in the slate rock 12, on which a layer of limestone 14 is superimposed, possibly a ground layer 16. A number of exhaust ducts 18 stand in connection with through lime and slate drilled gas drains 20. The heating elements 10 and the exhaust ducts 18 are simultaneously arranged in rows one after the other at an angle to the plane of the drawing. The gas drains 20 belonging to such a row iiro over connecting pipes 21 and shut-off resp. control valves 22, 23 connected to a collecting duct 24. A larger collecting duct 25 for a plurality of collecting ducts 24 in turn combines these with a condenser 26 and a washing tower 27, the shale oil gases on the edge of salt are cooled and as far as possible freed of condensable oil constituents. The capacitor 26, which can also be constituted by resp. include equipment for other chemical treatment of shale oil gases e.g. separation of sulfur or other by-products therein, is connected through a line 28 to a collection container 30 for the oil. In this container also opens a line 32 from the water tower 27. From a branch line 34 some of the non-condensed gases can be discharged through a line 36, in which a yentil 38 is inserted, for use as a fuel or for other purposes. Another part of the gases flows through a compressor device 40.

I en sektion av skifferberget begransad yinkelratt mot ritningsplanet av plan genom linjerna 42, 44 antages pyrolysen, d. v. s. en under varmetillfOrsel forsiggaende nybildning av skiffergaser vara avslutad. VarmetillforseIn till elementen 10 har har alltsa aybrutits. I stallet utvinnes for ogonblicket en sektion av skifferberget, begransad av linjerna 44-46. Vasmevagen forutstittes alltst yandra i riktningen av pilarna 48. Linjen 50 i fig. 2 representerar temperaturfordelningen i de hada sektionerna. Vid linjen 44 kan temperaturen hava uppnatt ett yarde, mellan 3400° G foretradesvis omkring 380° C. Temperaturen faller genom processen enligt uppfinningen riktning mot linjen 42. In a section of the slate rock bounded by an angle steering wheel towards the drawing plane of planes through lines 42, 44, the pyrolysis, i.e. a new formation of shale gases during heat supply, is assumed to be completed. Heat supply to the elements 10 has thus been interrupted. In the stable, a section of the slate rock is currently being extracted, bounded by lines 44-46. The wash carriage is predominantly spaced apart in the direction of the arrows 48. The line 50 in Fig. 2 represents the temperature distribution in the hot sections. At line 44, the temperature may have reached a yard, between 3400 ° C, preferably about 380 ° C. The temperature drops through the process according to the invention towards line 42.

Medan kanalerna 20 i sektionen 44-46 tjanstgora som avlopp for de i derma sektion utvunna skiffergaserna, bar minst en rad dylika kanater, SOM Sr belagen vid sektionens 42-44 bakkant, sett i varmevagens riktning enligt pilarna 48, och som a ritningen givits beteckningen 52, anslutits till kompressorns 40 trycksida via en samlingskanal 54. I gaskanalerna 52 bringas salunda de frail ledningen 34 kommande gaserna att itterstromma lilt det redan avgasade skifferberget inom omrSdet Indian linjerna 42 och 44. En del ay dessa aterstrommande gaser kunna avledas genom gasavlopp 56 och en samlingskanal 58 fran gaskanalen 60 inom detta omrade, for att efter lamplig behandling genom kondensation eller tvattning eller andra processer nyttiggoras resp. aterledas till ledningen 34. Eventuellt kunna kanalerna 60 vara hopkopplade med samlingsledningen 24. Resten av gaserna kunna under fortsatt stromning inom skifferbergets porOsa lagringar i pilarnas 48 riktning komma i kontakt med skifferberg inom sek tionen 44--46, day uppvarniningen ay skifferberget pagfir och dar alltsa skiffergaser under pyrolys avledas genom gaskanalerna 20. Genom astadkommandet av tillrilekligt hog tryckstegring hos gaserna efter kompressorn 40 kunna dessa saledes bringas att stromma i ett kretslopp med tvS olika forgreningar, dels en krets ansluten till passagerna 56, 34 sand sektionen 42-44 i skifferberget och dels en krets innefattande passagerna 18, 34 och bagge sektionerna 42-44 och 44-46 inom skifferberget. Sadana gaser vilka genoin nedkylning, kondensation och tvattning befrias fran oljan bringas saledes enligt uppfinningen att genomstri5mma skifferberget, dar de hi. a. kunna bidraga till en livligare transport av oljegaser fran skifferberget till kondensoranlaggningen genom den spolyerkan, som dylika gaser komma att prestera. Vid sidan av denna spolverkan avses emellertid enligt uppfinningen aven en annan verkan. Vid all oljeframstallning med avgasning direkt i skifferberget uppkommer alltid pa grand av det Eivertryek, som rader i berget vid aygasningen en del for-luster genom gaslackage mom berget upp mot markytan. Spriekor finnas har och van inom berget och det overlagrade kalkberget Sr i sig sjalvt icke fullkomligt tiitt. En mindre del av de framstallda oljegaserna kommer darfor att sa smaningom lacka at genom lackage i spriekor i marken ovanpa skifferberget. Enligt uppfinningen fylles redan avgasat skifferberg med tillhjalp av en kompressor med wiser dSr oljan redan utyunnits. Det lOckage, som darvid alit forfarande uppstar kommer pa sit salt att besta av lackande gaser, som icke innehalla nagon olja. Harigenom -vinnes enligt uppfinningen den fordelen, att oljeforluster genom Ifickage i markytan minskas. While the ducts 20 in section 44-46 serve as drains for the shale gases extracted in this section, at least one row of such ducts, which are located at the trailing edge of section 42-44, seen in the direction of the heating path according to the arrows 48, and which in the drawing are designated 52, connected to the pressure side of the compressor 40 via a collection duct 54. In the gas ducts 52, the gases coming from the frail line 34 are thus caused to re-flow to the already degassed shale rock within the area of Indian lines 42 and 44. a collecting duct 58 from the gas duct 60 within this area, so that after suitable treatment by condensation or washing or other processes, resp. redirected to line 34. Possibly the channels 60 may be connected to the collection line 24. The rest of the gases may during continued flow within the slate rock porOsa deposits in the direction of the arrows 48 come into contact with slate rock within section 44--46, day warning ay slate mountain pagfir and dar thus shale gases during pyrolysis are diverted through the gas channels 20. By causing a sufficiently high pressure rise of the gases after the compressor 40, these can thus be caused to flow in a circuit with tvS different branches, partly a circuit connected to the passages 56, 34 sand section 42-44 in the shale mountain and on the other hand a circuit comprising the passages 18, 34 and ram sections 42-44 and 44-46 within the slate rock. Such gases which are genuinely cooled, condensed and washed are freed from the oil are thus brought according to the invention to flow through the shale rock, where they hi. a. be able to contribute to a more lively transport of oil gases from the shale rock to the condenser plant through the coil can, which such gases will perform. In addition to this flushing action, however, according to the invention another action is also meant. In all oil production with degassing directly in the slate rock, the Eivertryek always arises, which lines up in the rock during the gasification, some loss is lost through gas coating on the rock up to the ground surface. Spriekor are found and used within the rock and the superimposed limestone mountain Sr itself is not completely tiitt. A small part of the produced oil gases will therefore gradually varnish by varnishing in spray cores in the ground above the slate rock. According to the invention, already degassed slate rock is filled with the aid of a compressor with a wiser when the oil has already been diluted. The leakage which still arises in its salt will consist of leaching gases which do not contain any oil. As a result, according to the invention, the advantage is gained that oil losses through Ifickage in the ground surface are reduced.

Vid oljeutvinning ur skiffer kan det antagas, att beroende pa de temperaturer och tryck, varunder pyrolysen fortgar, avensom beroende pa den hastighet, med vilken uppvarniningen av skiffern genomfores, pyrolysen genoinfOres under av de fysikaliska och kemiska betingelserna reglerade forhallanden, sa att olika substanser uthildas i ett kvantitatiyt balansfOrhallande till varandra. Salunda kan som exempel antagas att tIV den ut- bildade pyrolysgasen utgores av vate, en viss del av densamma av inetan och andra narslakLade kolvaten for att slutligen de oljebildande kolvatena pa grund av sin storre inolekylarvikt komnm att uppga. till en rnindre del av den totala gasvolymen. In the case of oil extraction from shale, it can be assumed that depending on the temperatures and pressures at which the pyrolysis proceeds, as well as depending on the rate at which the heating of the shale is carried out, the pyrolysis is introduced under conditions regulated by the physical and chemical conditions. in a quantitative balance relationship to each other. Thus, for example, it can be assumed that the pyrolysis gas formed consists of hydrogen, a certain part of it consists of inethane and other slaked hydrocarbons, so that eventually the oil-forming hydrocarbons, due to their greater inolecular weight, will give up. to a lower part of the total gas volume.

Sjalva pyrolysprocessen Sr av en sa komplicerad natur, att den ej for narvarande kan tillfredsstallande klarlaggas, men det praktiska resultatet tyder pa, att en dylik viss proportion mellan de olika kolyiitena alltid foreligger. Den genom ledningen 34 till skifferberget aterinforda gasen ar, sasorn av ovanstaende framgar, proportionsvis rikare pa Hite och lattare kolvaten an den unsprung- — —a liga pyrolysgasen, fran vilken de tyngre kolvatena utvunnits. I narvaro av skifferbergets stora porosa massa som kontaktsubstans och dar pyrolys langsamt pagar inom myeket stora volymer, kommer enligt uppfinningen over- skottet av vatgas och lattare kolvaten i den aterinforda gasen att paverka pyrolysen i den riktning att en balans stravar att aterstallas mot den ursprungligen utvunna pyrolysgasens sammansattning. Detta forhallande torde narmast kunna liknas vid en hydrering, men en- ligt uppfinningen ersattes de mycket hoga tryck, under vilka sadan hydrering brukar genomforas, i detta fall med en ofantlig kontaktyta i katalysatorn, som mojliggor att Mom rimlig tid uppna ett narmande till ett balanserat Thrhallande mellan de olika reaktionerna vid pyrolysen. Darvid binder mera kol vid det genom aterinforingen tillforda vatet, varigenom i koksen kvarblivande kol minskas till forman for en kvantitativ okning av de oljebildande gaserna. The process of pyrolysis itself is of such a complex nature that it cannot at present be satisfactorily clarified, but the practical result indicates that such a certain proportion between the various colloids is always present. The gas re-introduced through line 34 to the slate rock is, as shown above, proportionately richer in Hite and lighter in hydrocarbons than in the original pyrolysis gas from which the heavier hydrocarbons were extracted. In the presence of the large porous mass of the shale rock as a contact substance and where pyrolysis slowly picks up in very large volumes, according to the invention the excess of hydrogen gas and lighter hydrocarbons in the reclaimed gas will affect the pyrolysis in the direction that a balance is restored to the originally recovered the composition of the pyrolysis gas. This condition can almost be likened to a hydrogenation, but according to the invention the very high pressures under which such hydrogenation is usually carried out are replaced, in this case with an enormous contact surface in the catalyst, which makes it possible for Mom to achieve a reasonable to a balanced time. Thralling between the different reactions in the pyrolysis. Thereby, more carbon binds to the water supplied by the re-introduction, whereby carbon remaining in the coke is reduced to form a quantitative increase in the oil-forming gases.

Enligt uppfinningen passerar de gaser, ur vilka oljan utvunnits forst genom en poros bergmassa, dar oljeavdrivning redan är fullbordad. Harunder forvarmes sagda gaser, sedan de under passagen genom kondensor och tvattorn nedkylts till en lag temperatur, som I praktiken hailer sig omkring 0° eller lagre. Det redan avgasade skifferberget och den spillvarme som i detta varma berg kvarlamflats efter pyrolysen, utnyttjas salunda delvis for forvarmning av den vid pyrolysen medverkande cirkulationsgasen. Emedan en sadan gas' varmeinnehall Or relativt lagt, kan enligt uppfinningen den kvantitet gas, som cirkuleras beroende p. onistiindigheterna vdl- jas sa., att dess volym uppgiir till en h flera ganger den vid pyrolysen nybildade gasens volyrn. Harigenom underlattas det reaktionsforlopp, som har ovan antytts pa sa salt, att ett balansforhallande Mom de olika reaktioner- na joke behover narmelsevis uppnas pa grund av det stora overskott av lattare kolvaten och vate, som yid pyrolysen finnas tillgangliga. Genom denna rikligare gascirkulation intrader Oven det fOrhallandet, att sadana kolvaten, som lifsga ph gransomradet for forgasningen, ladare kunna avfOras ur skifferberget med tillhj alp av den rikligare gascirkulationen. De tyngsta kolvatena, som utan cirkulerande gas kvarbliva och forkoksas i berget, torde darfor med tillhjalp av gascirkulation helt eller delvis bringas att medfolja den all-manna gasstromningen. Enligt uppfinningen skapas saledes genom inforande av en eirkulerande gas Mom redan uppviirmt skiff er- berg nya mojligheter att erhalla en rikare produktion av de genom pyrolysen eftertraktade flytande kolvatena. Slutligen kan det tankas, att den stora bergkropp av varm skifferkoks, genom vilken cirkulationsgasen strommar sin vag till pyrolysomradet i skifferberget, ph b urund av sina enorma dimensioner och darmed forknippad katalysatorverkan direkt i viss man medger en hydrering av med koksen narslaktade kolvaten, som kvarstannal i densamma, varigenom restforlusten i form av koks nedbringas. According to the invention, the gases from which the oil is extracted first pass through a porous rock mass, where oil stripping has already been completed. During this, said gases are preheated, after they have been cooled during the passage through the condenser and the washing tower to a low temperature, which in practice rises to about 0 ° or lower. The already degassed shale rock and the waste heat left in this hot rock after the pyrolysis are thus partly used for preheating of the circulating gas involved in the pyrolysis. Since such a gas' heat content Or is relatively low, according to the invention the quantity of gas which is circulated depending on the conditions can be adjusted so that its volume amounts to one h several times the volume of the gas newly formed during the pyrolysis. This facilitates the reaction process indicated above in such a salty way that a balancing Mom the various reaction jokes need to be achieved due to the large excess of lighter hydrocarbons and water that are available during the pyrolysis. Due to this more abundant gas circulation, the condition also arises that such hydrocarbons, which live in the vicinity of the gasification, can be discharged from the slate rock with the aid of the more abundant gas circulation. The heaviest hydrocarbons, which remain and are coked in the rock without circulating gas, should therefore, with the aid of gas circulation, be brought to follow the general gas flow in whole or in part. Thus, according to the invention, by introducing an circulating gas Mom already created shale, new possibilities are created to obtain a richer production of the liquid hydrocarbons coveted by the pyrolysis. Finally, it is conceivable that the large rock body of hot shale coke, through which the circulating gas flows its vague to the pyrolysis region of the shale rock, ph b round of its enormous dimensions and associated catalyst action directly in some way allows a hydration of coke butchered coke, which remains in the same, thereby reducing the residual loss in the form of coke.

I stallet for pyrolysgaserna enligt ovan kunna andra gaser, t. ex. generatorgas komma i fraga for astadkommandet av olika onskade kemiska reaktioner under medverkan av den porosa varma skiffern. Instead of the pyrolysis gases as above, other gases, e.g. generator gases come into question for the production of various desired chemical reactions with the participation of the porous hot shale.

Claims

Patent claim:

1. sat during gasification of oil-bearing slate rock in situ while supplying heat through channels taken up in the slate rock, characterized by the fact that after a slate section has been degassed by pyrolysis and become porous, gases are introduced into this section, while it is otherwise hot, through others in the slate rock occupied ducts to the heat supply ducts and that these gases are of such a nature that they are subjected to chemical reactions without combustion with the slate rock serving as. catalyst.

2. Claimed in claim 1, characterized in that at least a part of the gas formed during the pyrolysis is reintroduced into the shale portion, after it has been deprived of its oil-bearing constituents by condensation or quenching during cooling.

3. Set according to claim 1, characterized in that the introduced gas is caused by a compressor device to flow through a portion of already degassed hot slate erberg to be introduced from there into another rock portion, where oil recovery pagan

4. According to patent claims 1-3, it can be claimed that a part of the recycled gas is taken out of the Iran slate before that night in the zone in which degassing of slate ph-g, while another part is allowed to pass above this zone.

5. According to one of the preceding patent claims, characterized in that the gases are introduced into the shale rock through channels which during the pyrolysis served as gas drains. NWT: holm 1948. lima Boktr. IN'. A, Norstea & Siker 480080