SE126674C1 - - Google Patents

Description

Translated fromSwedish

Uppfinnare: F. Ljungstrom. Inventor: F. Ljungstrom.

I patenten 121 737 och 123 136 har det 16- reslagits, att medelst i kanaler i ett skifferberg nedstuckna elektriska varmeelement, uppvarma detsamma, sâ att pyrolys framkallas. De darvid bildade oljegaserna avensom andra gaser uttagas genom sarskilda avloppskanaler i berget i och for uppsamling och nyttiggOrande genom kondensation och andra processer. Uppfinningen avser bl. a. att genornfOra denna uppvarmningsprocess, sa att den for densamma erforderliga energien erhalles till lagre kostnad an hittills och sa att alltsâ framstallningsmetoden fOr oljan nedbringas. Ett annat andamal ãr att a.stadkomma en uppvarmningsprocess, i vilket skifferberget tjanstg5r sa att saga som en ackumulator for billig ,elektrisk energi, soin alltst tillvaratages i form av varme och ,darmed kommer en vid senare tillfalle genomfortl pyrolys tillgodo. Ytterligare ett andamal är att astadkomma en forpreparering av skifferberget, sh att lackage av de yid pyrolysen utvunna produkterna verksamt f8rhindras.In patents 121,737 and 123,136 it has been proposed that by means of electric heating elements embedded in channels in a slate rock, it be heated so that pyrolysis is induced. The resulting oil gases, like other gases, are extracted through special drainage channels in the rock for collection and recovery through condensation and other processes. The invention relates, inter alia, to a. to carry out this heating process, so that the energy required for it is obtained at a lower cost than hitherto, and so that the production method for the oil is thus reduced. Another purpose is to bring about a heating process, in which the slate mountain serves as a sawmill as an accumulator for cheap, electrical energy, which is always utilized in the form of heat and, thus, in a later case, complete pyrolysis will benefit. Another aim is to achieve a pre-preparation of the slate rock, so that the lacquering of the products recovered from the pyrolysis is effectively prevented.

Dessa aven som andra andamal och i ovrigt uppfinningen kannetecknande egenskaper skola nannare beskrivas i det foljande, varvid a bilagda ritning schematiskt askadliggjorts ett utforingsexempel av uppfinningen. Harvid visa: Fig. 1 en vertikalsektion genom ett skifferberg och fig. 2 och 3 tvenne diagram. A ritningen betecknar 10 ett olj eforande skiff erlager, a vilket kan vara Overlagrat ett kalkbergsskikt 12 och eventuellt ett jordskikt 14. I vertikalt borrade kanaler aro nedstuckna ett start antal elektriska varmeelement 16, anordnade att avgiva sitt varme till skifferlagret 10. For en narmare beskrivning av dessa varmeelements avensom avloppskanalernas utformning och anbringande hanvisas till ovannamnda patent. Varmeelementen 16 sta medelst grenledningar 18 i forbindelse med ett elektriskt kraftledningssystem 20, varigenom lagspand strom inmatas i varmeelementen. &Isom avenledes framgar av dessa patent genomfores uppvarmningen av skifferberget ph sa salt, att en horisontellt vandrande varmefront skapas, vars riktning i fig. 1 betecknas med 22. I enlighet med uppfinningen delas uppvarmningen av skifferberget i Iva steg, en forvarmning och en efterfoljande uppvarmning till slut-hg temperatur, nedan benamnd pyrolysuppvarmningen. Vid uppvarmning av skiff ern intraffar en oljebildande pyrolys vid en temperatur, som overstiger 250° C, och Hirst i n.arheten av 300° b5rja oljegaserna och andra kolvategaser att i namnvard grad bildas. Mellan t. ex. 300° och 400° pa& den livligaste pyrolysen, d. v. s. mom detta omrade bildas i huvudsak all den olje- och gasmangd, som under den elektrotermiska olj eframstallningen frambringas. FOrvarmningen bedrives nu vid det Li ritningen askadliggjorda utforingsexemplet mom ett omrade av skifferberget begransat av de streckprickade linjerna 24, 26, varvid de mom detta omrade befintliga varmeelementen aro kopplade till kraftledningen 20. Temperaturen stiger darvid gradvis genom successiv inkoppling av nya rader av varmeelement 16, enligt kurvan 30 i fig. 2, vars abskissa angiver skifferfaltets enligt fig. 1 ytutstrackning i varmefrontens riktning, medan dess ordinata angiver temperaturen i skifferberget. Under forvarmningen upphettas skifferberget till en temperatur svarande mot linjen 32 i fig. 2, dar nagon vasentlig pyrolys dnnu ej uppkommit, t. ex. 240° a 280°. Pyrolysuppvarmningen bedrives mom ett parti av berget begransat av linjern.a 34, 36, vilket parti ãr skilt Iran forvarmningspartiet. Under pyrolysuppvarmningen stegras bergets temperatur stegvis enligt kurvan 38 till den slutliga temperaturemi enligt linjen 40, som kan uppga. till 360° a 420°. Efter en viss tids fOrlopp ken forvarmningen have natt fram till kurvan 30° och pyrolysuppvarmnin.gen till kurvan 38°. I skifferberget finnas alltsa tva skilda uppvarmningszoner, som. -vandra framat i samma riktning.These, like other objects and other features of the invention, may be described in more detail below, in which the accompanying drawing schematically illustrates an exemplary embodiment of the invention. In this case: Fig. 1 shows a vertical section through a slate mountain and Figs. 2 and 3 two diagrams. In the drawing, 10 denotes an oil-bearing slate bearing, which may be superimposed on a limestone rock layer 12 and possibly an earth layer 14. In vertically drilled channels a starting number of electric heating elements 16 are arranged, arranged to give off their heat to the slate layer 10. For a more detailed description of these heating elements as well as the design and application of the drainage channels are referred to the above-mentioned patent. The heating elements 16 are connected by means of branch lines 18 in connection with an electric power line system 20, whereby layered current is fed into the heating elements. As is clear from these patents, the heating of the slate rock ph so salt is carried out, that a horizontally traveling heating front is created, the direction of which in Fig. 1 is denoted by 22. In accordance with the invention, the heating of the slate rock is divided into Iva steps, a preheating and a subsequent heating to final-hg temperature, hereinafter referred to as the pyrolysis heating. When the shale is heated, an oil-forming pyrolysis occurs at a temperature exceeding 250 ° C, and near 300 ° Hirst the oil gases and other piston gases begin to form to a nominal degree. Between e.g. 300 ° and 400 ° pa & the liveliest pyrolysis, i.e. in this area, essentially all the amount of oil and gas formed during the electrothermal oil production is formed. The preheating is now carried out in the embodiment of the slate which is damaged in the drawing, in one area of the slate mountain bounded by the dashed lines 24, 26, the existing heating elements in this area being connected to the power line 20. The temperature rises gradually by successive connection of new rows of heating elements according to curve 30 in Fig. 2, the abscissa of which indicates the surface extent of the slate field according to Fig. 1 in the direction of the heat front, while its ordinate indicates the temperature in the slate rock. During the preheating, the slate rock is heated to a temperature corresponding to line 32 in Fig. 2, where no essential pyrolysis has yet arisen, e.g. 240 ° and 280 °. The pyrolysis heating is carried out with a portion of the rock bounded by lines 34, 36, which section is separate from the Iran preheating section. During the pyrolysis heating, the temperature of the rock rises stepwise according to curve 38 to the final temperature chemistry along line 40, which may indicate. to 360 ° and 420 °. After a certain period of time, the preheating has reached the 30 ° curve and the pyrolysis heating to the 38 ° curve. In the slate mountain there are thus two different heating zones, which. -wander forward in the same direction.

Under forvarmningen tillf5res vid ovansthende exempel omkring tvd tredjedelar av den erforderliga varmemangden till skiffer- 2— — berget och under pyrolysuppvarmningen endast omkring en tredjedel darav. Medan forvarmningen kan bedrivas periodiskt, sker pyrolysuppvarmningen mojligast kontinuerligt, vilket har en fordelaktig inverkan pa produktionen. Som exempel ma antagas det fallet, att forvarmningen endast ager rum under hal-va aret. Det ma antagas, att samma energimangd alltid tillfores, ett varmeelement per tidsenhet. Eftersom tva tredjedelar .av den totala varmemangden tillf0- res under forvarmningen, skall tydligen tinder denna fyra ganger sa manga varmeelement som under pyrolysuppvarmningen vara inkopplade, vilket innebar, att dubbla Tarmemangden 'Mores pa halva tiden. Vandringshastigheten hos den av linjerna 24, '26, begransade forvarmningsfronten blir samtidigt dubbelt sa stor som vandringshastigheten for pyrolysfronten mellan linjerna 34, 36. Det inses hara-v, att mellan de hada uppvarmningsfronterna kommer att forefinnas ett parti av skifferberget av varierande langd. Detta parti har nâtt temperaturnivan enligt linjen 32, d. v. s. bringats upp till den ternperatur, vid vilken pyrolysen kan paborj as. Da forvarmningen är avbruten minskas avstandet mellan linjerna 26 och 34; nar aterigen forvarmningen igangsattes Ras detta avstand.During the preheating, in the above example, about two thirds of the required amount of heat is supplied to the slate rock, and during the pyrolysis heating only about one third of it is supplied. While the preheating can be carried out periodically, the pyrolysis heating takes place as continuously as possible, which has a beneficial effect on production. An example is the case where the preheating only takes place during half the year. It must be assumed that the same amount of energy is always supplied, one heating element per unit of time. Since two thirds of the total heating amount is supplied during the preheating, it must apparently be four times as many heating elements as during the pyrolysis heating must be connected, which meant doubling the intestinal amount 'Mores in half the time. The migration speed of the preheating front delimited by lines 24, '26 will at the same time be twice as fast as the migration speed of the pyrolysis front between lines 34, 36. It will be appreciated that between the hot heating fronts there will be a portion of the slate rock of varying length. This portion has reached the temperature level along line 32, i.e. has been brought up to the temperature at which the pyrolysis can be started. When preheating is interrupted, the distance between lines 26 and 34 is reduced; when again the preheating was initiated Ras this distance.

Detta avbrott i varmetillforseln till ,skifferberget, sedan detsamma natt temperaturnivan 32, medfor ett flertal mycket betydelsefulla fOrdelar. Under det att varme tillfores ett varmeelement 16 far skifferberget omkring detsamma aka temperatur, i det att denna faller i riktning fran elemenet enligt kurvan 42 i fig. 3. I denna figur är den mot kurvan 42 svarande abskissan betecknad med 44. Sedan den elektriska energien frankopplats, utj amnas temperaturen enligt kurvan 46. Skiff erberget kommer alltsâ pa grund air intervallet Indian de bada uppvarmningsperioderna att uppvisa en mera fullbordad utjamning av temperaturen inom det uppvirmda bergpartiet. Ett .skifferberg har en yarmeutvidgningskoefficient air omkring 0,c000l. Pa de distanser om 2-3 in, som forekomma mellan de olika varmeelementen 16, bliva darvid med de ternperaturskillnader, som framga av kurvan 42 i fig, 3 (t. ex. 2000) de av uppvarmningen framkallade utvidgningarna av olika partier hiigst variabla mom skifferberget, varvid mycket ojamna varmespanningar framkallas inom desamma. I allmanhet forefinnes emellertid en tendens till varmeansvallning i horisontell riktning, framkallad av bergets generella uppvarmning. Denna varineansvallning tenderar till att sammanpressa alla vertikalsprickor, som finnas mom skifferberget, och verkar därfOr tatande pa dessa sprickor. Emellertid uppstd under forvarmningsperioden a ena sidan mom berget partiella zoner, som vilja sammantrycka de ovannamnda sprickorna och a andra sidan andra zoner dar en sadan sammantryckning forhindras. Vid utjamningen av temperaturen under intervallet mellan de bada uppvarmningsperiodema blir sammantryckningen air forekommande sprickor mera generell och darigenom mera effektiv. Genom avbrott i varmetillforseln motverkas salunda i mycket langtgaende grad, att de vid pyrolysuppvarmningen alstrade gaserna taga lake onskade vagar. Vidare medfor uppfinningen f8rdelar i det ekonomiska slutresultatet vid elektrotermisk utvinning a-v olj a. Forvarmningsperioden kan med fordel verkstallas under sadana ti-der, da billig vattenkraft i relativt overfl8d finnes tillganglig. Uppfinningen erbjuder darvid ett formanligt alternativ till de elektriska angpannor, dar som bekant elektrisk energi anvandes for angframstallning Pyrolysuppvarmningen verkstalles under relativt jamn tillforsel air elektrisk energi. Den harlot' erforderliga varmetillforseln kan lampligen ut0- b Ora en mindre del av hela den tillforda varmemangden enligt ovanstaende.This interruption in the supply of heat to, the slate mountain, since the same night the temperature level 32, entails a number of very significant advantages. While heat is supplied to a heating element 16, the slate rock rises around the same aka temperature, in that it falls in the direction of the element according to the curve 42 in Fig. 3. In this figure, the abscissa corresponding to the curve 42 is denoted by 44. Then the electrical energy disconnected, the temperature is equalized according to curve 46. The skiff rock will thus, due to the air interval Indian the two warming periods, show a more complete equalization of the temperature within the heated rock section. A slate mountain has a coefficient of thermal expansion air around 0, c000l. At the distances of 2-3 in, which occur between the different heating elements 16, the expansions of different parts caused by the heating of the most variable conditions are produced with the temperature differences, which appear from the curve 42 in Fig. 3 (eg 2000). the slate rock, whereby very uneven heat stresses are produced within them. In general, however, there is a tendency for heat to swell in the horizontal direction, caused by the general heating of the rock. This swelling of the veins tends to compress all the vertical cracks that are present in the slate rock, and therefore acts on these cracks. However, during the preheating period, partial zones arise on the one hand, which want to compress the above-mentioned cracks, and on the other hand, other zones where such compression is prevented. When the temperature is equalized during the interval between the two heating periods, the compression of the cracks occurring becomes more general and thereby more effective. By interrupting the heat supply, it is thus counteracted to a very far-reaching degree, that the gases generated during the pyrolysis heating take lake desired scales. Furthermore, the invention has advantages in the economic end result of electrothermal recovery of oil. The preheating period can advantageously be effected during such times, when cheap hydropower in relative abundance is available. The invention thereby offers a formable alternative to the electric steam boilers, where as is known electrical energy is used for steam production. The pyrolysis heating is carried out under a relatively even supply of electric energy. The required heat supply can suitably account for a small part of the entire supplied heat amount according to the above.

Vid elektrotermisk skifferolj eframstallning alstras dels oljebildande gaser, vilka genom kondensation tillvaratagas i flytande form, och dels Liven andra gasformiga kolvaten jamte vatgas, som endast med star svarighet under laga temperaturer kunna kondenseras och som darfor ham nedan kallas icke kondenserbara gaser. Dessa gaser utgora i allmanhet balm a mangden av samtliga utvunna kolvaten och hava ungefar samma effektiva forbranningsvarde, som de flytande kolvatena. For varje liter producerad olja erhalles salunda samtidigt omkring 1 in' gas. Denna gas dr ett utmarkt bransle och har, anvant pa ratt satt, ett stort kommersiellt varde, likvardigt med oljans, men densamma ãr med hansyn till distributionen och ftirsaljningsmojligheterna lake lika latthanterlig som oljan. Eli omfattande gasledningsnat och stora anlaggningskostnader komma saledes att folja en distribution av gasen, och skulle all gas distribueras fran ett stalle ddr t. ex. 200000 In' olja arligen framstalles, uppsta betydande svarigheter. I den man som i gasen befintliga bestandsdelar icke pa platsen kunna tillvaratagas (svavel m. m.) anvandes densamma i stallet lampligen sasom bransle i en kraftcentral som alstrar elektrisk energi, vii-ken enligt uppfinningen eventuellt alternativt med annan t. ex. Iran vattenkraft tillford energi appliceras f Or pyrolysuppvarnmingen av skifferberget. Uppvarmes nu skifferberget enligt uppfinningen pa ovan beskrivna satt, erhalles a ena sidan en periodisk forvarmning ay skifferberget, under det att a andra sidan en jamnt eller nara jamnt fortskridande pyrolysuppvarmning genom tillforande air elektrisk energi kan ordnas fran den gaseldade kraftcentralen. Pyrolysuppvarmningen kan alltsa genom lampligt avvagande av den — —3 temperatur, till vilken berget under fOruppvarmningen upphettas, bedrivas utan yttre energitillskott i form av vattenkraft. Pyrolysuppvarmningen fortgar darunder kontinuerligt oberoende av forvarmningen, som kan periodiskt ordnas, anpassad t. ex. efter tillgangen pa overflodeskraft fran vattenkrafteentralerna. Angcentralen far tydligen pa detta satt en kontinuerlig och darest sa onskas jamn belastning och vad som är av sarskild vikt, pyrolysen pagar i ett jamnt och ()start forlopp, oberoende av vattenkraftens konjunkturforhallanden. Emellertid kan pyrolysuppvarmningen bedrivas med olika intensitet under olika perioder resp. arstider, genom att olika antal -varmeelement aro samtidigt inkopplade i stromnatet. I land, t. ex. av Sveriges storlek och naturforhallanden mojliggar uppfinningen, alt under alla forhallanden overskottsenergi eller sa kallad sekundarkraft fran vattenkraftverken kan ekonomiskt formanligt finna anvandning for framstallning av flytande bransle. Skiff erberget utgor ddrvid genom farvarmningen en ackumulator, som i form ay varme tar vara pa vattenkraftsenergi, som sedan vid, om sa onskas, en langt senare tidpunkt kan utnyttjas for den slutliga. oljeutvinningen.In electrothermal shale oil production, oil-forming gases are generated, which are recovered in liquid form by condensation, and Liven other gaseous hydrocarbons as well as hydrogen gas, which can only be condensed at low temperatures under low temperatures and which is therefore called non-condensable gases below. These gases generally account for the amount of all recovered hydrocarbons and have approximately the same effective calorific value as the liquid hydrocarbons. For every liter of oil produced, about 1 in 'gas is thus obtained at the same time. This gas is an excellent industry and, used in the right way, has a large commercial value, equivalent to that of oil, but the same is true with regard to distribution and sales opportunities, as easy to handle as oil. Eli extensive gas pipeline night and large construction costs will thus follow a distribution of the gas, and would all gas be distributed from a stable ddr e.g. 200000 In 'oil annually produced, arise significant responsibilities. In the case where the constituents present in the gas cannot be recovered on site (sulfur, etc.), the same was used instead as a branch in a power plant which generates electrical energy, which according to the invention may alternatively with another e.g. Iran hydropower supply energy is applied f Or the pyrolysis warming of the slate rock. If the shale rock according to the invention is now heated in the manner described above, on the one hand a periodic preheating of the shale rock is obtained, while on the other hand an even or near evenly progressing pyrolysis heating by supplying electrical energy can be arranged from the gas-fired power plant. The pyrolysis heating can thus be carried out without suitable external energy in the form of hydropower by suitable balancing of the temperature at which the rock is heated during the preheating. The pyrolysis heating continues continuously independently of the preheating, which can be arranged periodically, adapted e.g. after the supply of abundant power from the hydropower plants. The steam center apparently has a continuous and, if desired, even load in this way, and what is of particular importance, the pyrolysis proceeds in a smooth and () start-up process, regardless of the economic conditions of hydropower. However, the pyrolysis heating can be carried out with different intensities during different periods resp. times, in that different numbers of heating elements are simultaneously connected in the current. On land, e.g. of Sweden's size and natural conditions, the invention is possible, or under all conditions surplus energy or so-called secondary power from hydropower plants can be used economically for the production of liquid fuel. The skiff erberg then forms an accumulator through the heating, which in the form of heat takes advantage of hydropower energy, which can then, if desired, be used for the final one at a much later time. oil recovery.

Enligt uppfinningen kan angkraftcentralen eldas antingen enbart med gas frail pyrolysprocessen eller kan densamma eldas med andra brdnslen, beroende pa konjunkturforhallandena vid vane .sarskilt tillfalle. Salunda kan gasen under vissa perioder Tara kilt att avyttra, som t. ex. under vin-tern for stadernas fOrseende med gag. Under sommaren, da dylik gaskonsumtion är mindre, kan angcentralen eldas enbart riled gasen .eller med lamMig kombination av gas °eh andra branslen. Enligt uppfinningen kan saledes aven den icke kondenserbara gasen nyttiggoras pa sarskilt gynnsaint satt, varvid kombinationen av d ena sidan .ett periodvis uppvarmt skifferberg, dar forvarmningen pagar, ackumulerar och utnyttjar tillganglig billig vattenfallsenergi, samtidigt som a andra sidan pyrolysuppvarnmingen kan verkstallas enbart med den genom pyrolysen framkommande icke kondenserbara gasen, varvid denna anvandning av gasen avenledes kan ske periodiskt i vaxelverkan med gasens anvandning far andra andamal. liven i dylikt fall an det tankbart att variera pyrolysuppvarmningens intensitet genom andring av antalet .strOmforande varmeelement 16 f8r att avpassa den per tidsenhet framstallda olje- resp. gasmangden och at*igen av elenergi efter prisforhallandena. En periodisk drift av foryarmningen kan i allmanhet tankas genomf8rd synkront med arstiderna. Pa sommaren finnes t. ex. i re-gel overskott av elektrisk energi tillganglig samtidigt som under denna arstid t. ex. gaskonsumtionen i staderna nedgar till mindre an halften mot under vintertiden. Genom den under sommaren uppackumulerade forvarmningsenergien kan darfOr enligt uppfinningen angkraftverken pa vintern bidraga till den elektriska energiforsorjningen genom eldning med andra branslen an gasen, samtidigt som den under samma tid tillverkade pyrolysgasen anvandes i stadernas gasdistribution och dar betingar ett hogre varde an i form av angpannebransle. Enligt uppfinningen majliggores en framstallning av t. ex. skifferraolja pa elektrotermisk vag ur de relativt oljefattiga svenska skiffrarna med sa god ekonom!, att denna olja kan i kostnadsayseende konkurrera med utifran importerade oljor.According to the invention, the steam power plant can be fired either only with gas from the pyrolysis process or it can be fired with other fuels, depending on the economic conditions in the usual case. Salunda can the gas during certain periods Tara kilt to sell, such as. during the winter for the provision of the cities with gag. During the summer, when such gas consumption is lower, the steam plant can be fired only on the riled gas .or with lamMig combination of gas ° eh other industries. According to the invention, the non-condensable gas can thus also be utilized in a particularly favorable manner, the combination of on the one hand being a periodically heated slate rock, where the preheating paves, accumulates and utilizes available cheap waterfall energy, while on the other hand the pyrolysis heating can be effected only by pyrolysis resulting in the non-condensable gas, whereby this use of the gas can, by contrast, take place periodically in interaction with the use of the gas for other purposes. In such a case, it is conceivable to vary the intensity of the pyrolysis heating by changing the number of flowing heating elements 16 in order to adapt the oil produced per unit time. the amount of gas and at * again of electricity according to the price conditions. A periodic operation of the forearm can generally be carried out synchronously with the seasons. In the summer there are e.g. as a rule surplus of electrical energy available at the same time as during this season e.g. gas consumption in the cities decreases to less than half compared to during the winter. Due to the pre-accumulated preheating energy during the summer, the steam power plants in the winter can therefore contribute to the electrical energy supply by firing with other industries than the gas, while the pyrolysis gas produced during the same time is used in urban gas distribution. According to the invention, a preparation of e.g. shale crude oil on electrothermal vapor from the relatively oil-poor Swedish shales with such good economics that this oil can compete in terms of cost with imported oils.

Den gaseldade kraftcentralen kan givetvis vara forsedd med angturbiner eller gasturbiner eller andra moderna varmekraftmotorer.The gas-fired power plant can of course be equipped with ang turbines or gas turbines or other modern thermal power engines.

Storleken has Sveriges skifferforekomster tillata att enligt uppfinningen mycket stora varmekraftcentraler (100 MW och mera) komma till anvandning. Enligt uppfinningen kun.na dessa krafteentraler samtidigt las disponibla sasom reserv fOr vattenkraften inorn landet saint for upptagandet av spetsbelastningar a statens kraftnat. Under spetsbelastningarna kan en krafteentral saledes alternativt anvandas, antingen for skiff eroljeframstallning eller som statens reservkraftverk under torra dr, da oljeframstallningen eventuellt kan avstallas.The size of Sweden's shale deposits allows, according to the invention, very large thermal power plants (100 MW and more) to be used. According to the invention, these power plants could at the same time be made available as a reserve for hydropower within the country for the absorption of peak loads by the state. During peak times, a power plant can thus alternatively be used, either for shale oil production or as the state's reserve power plant during dry dr, as the oil production can possibly be stored.

Claims (5)

Translated fromSwedish

Patentansprak:Patent claim:1. Satt att framstalla skifferolja genom elektrotermisk pyrolys dtrekt i ett skiff en-berg, kannetecknat darav, att tva uppvarmningszoner skapas i skifferberget, i en av vilka detta foruppyarmes, medan redan farvarmt skifferberg underkastas pyrolysuppvarmning i den andra zonen, och att till bada tillfores elvarme dock under skilda betingelser i avseende pa tiden pa sa salt, att melIan foruppyarnmingszonen och pyrolysuppvarmningszonen befinner sig ett foruppvarmt bergparti av i horisontell led varierande bredd.1. Set to produce shale oil by electrothermal pyrolysis in a slate-rock, characterized in that two heating zones are created in the shale rock, in one of which this is preheated, while already heated shale rock is subjected to pyrolysis heating in the other zone, and to both electric heating, however, under different conditions with respect to the time at such a salt, that between the preheating zone and the pyrolysis heating zone there is a preheated rock section of horizontally varying width.2. Satt enligt patentanspraket 1, kannetecknat darav, att en zon av skifferberget forst forvarmes medelst diskontinuerligt tillfort elvarme, under det att en annan zon av skifferberget, som yid en tidigare tidpunkt blivit forvarmd, uppyarmes till hogre temperatur, -vid vilken pyrolys ager ruin, av tillfort elvarme aven under perioder, da tillforseln av elvarme till den forstnamnda zonen av skifferberget är avbruten.2. Put according to claim 1, characterized in that a zone of the slate rock is first preheated by discontinuous supply of electric heat, while another zone of the slate rock, which has been preheated at a previous time, is heated to a higher temperature, at which pyrolysis is ruined. , of supplied electric heat even during periods, when the supply of electric heat to the first-mentioned zone of the slate rock is interrupted.3. Satt enligt patentanspraket 1 eller 2,, kannetecknat darav, att det for pyrolysuppvarmningen av skifferberget erforderliga elvarmet tages fran ett kraftverk, eldat atminstone delvis med pyrolysgaser, framkomna genom pyrolysprocessen i berget. — —3. A set according to claim 1 or 2, characterized in that the electric heat required for the pyrolysis heating of the shale rock is taken from a power plant, fired at least in part with pyrolysis gases, produced by the pyrolysis process in the rock. - -4. Satt enligt nagot av de foregaende patentanspraken, kanneteeknat darav, att skifferberget uppvarmes under forvarmningen over ett storre temperaturintervall an under pyrolysuppvarmningen.4. According to some of the preceding patent claims, it may be characterized in that the slate rock is heated during the preheating over a larger temperature range than during the pyrolysis heating.5. Solt enligt nagot av de foregaende patentanspraken, kanneteeknat darav, att Mrvarmningen bedrives under tillforsel av storre elmangder per tidsenhet an pyrolysuppvarmningen. Stockholm 1949. Kungl. Boktr. P. A. Norsteclt & Miner 1900395. Solt according to any of the preceding patent claims, may be characterized by the fact that the heating is carried out with a supply of larger amounts of electricity per unit of time than the pyrolysis heating. Stockholm 1949. Kungl. Boktr. P. A. Norsteclt & Miner 190039