US2641565A - Treatment of shale - Google Patents

Description

June 9, 1953 R. T. sANDERsON TREATMENT OF SHALE 2 Sheets-Sheet l Filed April 14, 1948 June 9, 1953 R. T. sANDERsoN 2,641,565

TREATMENT OF SHALE Filed April 14, 1948 2 Sheets-Sheet 2 @om 43 Q7 46 A INVENToR.

Patented June 9,v 1953 u 2,641,565 TREATMENT oF SHALE Robert T. Sanderson; Fishkill, N. Y., assignor to The -TexasCompany, New York,` N'. Y., a cor` poration of Delaware Appueatibnnprii 14, 1943senljNqsv (c1. 195er 4 Claims.

This invention relates to the treatment and recovery of hydrocarbons, bituminous substances, and the like from shale and similar formations.

The recovery and improvement of oil or socalled kerogen, supposedly a complex bituminous mixture, from shale is a major problem of long standing because of the close association of the kerogen with the inorganic mineral aggregate and the necessity of handling such large quan-Y tities of the latter. Processes such -as destruc tive distillation, solvent extraction at high temperatures and high pressures, and hydrogenation at hightemperatures and pressures in the presence of a catalyst have been practicedto some extent but are generally regarded as unsatisfactory because of the relatively low yields obtained and the large quantities ofA aggregate that must be handled and brought up to the requiredhigh temperatures. In some cases the mineral aggregate may run as high as 75% or more.v

It is an object of this invention to provide a novel process wherein the hydrocarbon and bituminous contents of shale and like materials can be separated therefrom and recovered 'at minimum expense and without the necessity of bringing the mineral aggregate` up to and handling itA at high temperatures.

Another object of the invention is to provide a novel process for handling shale wherein the kerogen content thereof can be separated and recovered at relatively low temperatures, the physical characteristics thereof being materially improved. y

Other objects and advantages of the invention will become apparent from the following description and claims taken in connection with the attached drawing wherein Fig. 1 illustrates onel method of practicing the process of the invention.

leased -and made availablel for recovery'.A Such processing is preferably carried out at substanl tially'atmospheric temperatureor at ytemperature slightly above to avoid the loss of Aheat incident toheating the inorganic aggregate.- 7

The term microorganisms asused herein is intended to includemold, fungi, and bacteria as well as the enzymesand other productsthereof that are capable of` effecting alterations or liberation of lighter and more mobile hydrocar'- bons from the shale aggregate. The former is indicated by reaction products containing sulfur, hydrogen sulfide, and ammonia, and the latter Y by the apparent reduction in viscosity of the Fig. z'illustrates a modication of the method of Fig. 1, both methods being illustrated diagrammatically.

Broadly stated, the presentv invention relates to a method of processing shale and like material'wherein the shale is subjected to the action of microorganisms capable of metabolizing cer- -t'ain constituents of the kerogen content of the shaleand effecting both separation and recovery of the kerogen as well' as alteration products thereof from the, shalev while simultaneously improving the properties of Vthe kerogen and "ccnl verting it* to satisfactory types of oils. 'More hydrocarbon. An additional theory regarding the latter is that the microorganisms tend 'to split the long chain hydrocarbons into shorter chains. `There* is also some basis for believing' that the microorganisms produce some acids or acidic substances from the nutrient medium and constituents of the kerogen as` throughv a reduction of` the sulfur or nitrogen in theshale and those acids or acidic substances attack and dissolve certain constituents of the mineral aggregate, thus releasing the kerogen. This isindicated by the presence of some carbon dioxide in the gaseous reaction products.

Suitable microorganisms for the process include Clostridium sporogenes, Clostzclium histol'z itz'cu111vv Clostridium Zentoputrescens and faculative anaerobic microorganisms such as Pseudomonas fiuorescens which are able to metabolize the desired constituents in a nutrient medium such as a mineral type medium oftheffollowing general composition:

(NHolsm` 2.0

To thev above, 5%v yeast extract by weightY is Prfelably addedlas, a` source; ofbioticl. factor. v

known in the art. The pressure appears variable over a considerable range, substantially atmospheric pressure being preferred for economic and engineering reasons.

the process, attention is called to Fig. 1 of the accompanying drawing wherein II indicates a hopper for the shale or similar material as origia 44; a source 45 of fresh inoculated nutrient medium leading to a line 46, a pump 4l and an inlet 48 to reactor 4I; and a discharge line 49 for nally mined; I2 is a mill for grinding the. shale,

into relatively fine particles; I3, I4 and l5 are treating receptacles ortanks to which the ground shale isdistributed by conduits I6, Il and I8` 1eading from a manifold I9 connectedV in turn to mill I2 byv connection 2|; 22,23 and 24'are connections f'or charging nutrient medium with'its contained microorganisms to the treating tanks; 25,

` 26 and 2l are 'manifolds connected tothe several tanks for removing'liquid reaction products at different levels; Y28 is a manifold'connecting the Yindividual manifolds 25, 23 and 2l to a manifold discharge 29 3l, 32 and 33 are valve-controlled outlets for the processed aggregate and its surrounding nutrient medium after thefpro'cessing is completedfand 34,35 and 35 are outlets for the gaseous products, all being connected to a common conduit 31. 4 4

n carrying out the process, shale in hopper I I is groundv in mill I2 into iine particles and charged to tanks I3, I4vand I5. 'A nutrient medium inculated with the microorganisms to be used is preferably charged rst to the tanks through connections 22, 23 and 24 so that the shale falls into themedium, although it is to be understood that the ymedium may be added after the shale. The nutrient medium, when charged, is preferably of the desired pH. If it is found that the shale constituents have an appreciable effect `on the pH of the medium, the pH of the medium, as introduced, can be so adjusted that the final pH attained bythe shale and medium mixture is in the desired range.

The shale and medium are combined in proportions to form a slurry which can be agitated as by'mechanical means to maintain the solid particles of theV shale in suspension. This insures intimate and continued contact of the microorganisms with the shale particles. Agitation can also be accomplished by the introduction of a suitable gas.

Any gaseous products formed are removed through outlets 34, 35and 36. Separated oil or processed kerogen rises to the top of the nutrient medium and is withdrawn through the valved connections leading tol outlets 25, 2E and 21. These liquid'products may be subsequently processed and refined as desired in accordance with recognized reiery practice. a

`Suitable heating means may be provided in the form of steam coils or the like tovmaintain the temperature in the tanks within the desired range.

AftertheY shaleV has been processed, the'valves at the bottommof. the tanksvareopened and the' aggregate and medium withdrawn. The valves are closed and new chargesof inoculated medium and shale chargedv to the tanks. j Dependent Yupon the processing time and the capacityand number of the tanks used, the process maybe made Substantially continuous as re.- gards the shale fed by hopper II and the liquid products taken off through outlet 29, one or more of the tanks being discharged and charged while nutrient and product from the top of reactor 4I oilor like `product is sepa-rated from the medium Vand drawn'off through a line 52, exhausted medium-is renewed-through a line 53 and any gaseous products are removed through line 54.

It is contemplated that reactor 4I be operated continuously or batchwi'se. When operated continuously, the'iiow of Vshale through the indicated valves in inlets 42 and outlet 43 is adjusted so that the shale discharged at43 is virtually Vdenuded of its kerogen.

With either method of olgeration,"inoculated medium 'issupplied from source 45th'rou'gh line 43 tothe reactor, thoroughly mixed with the shale as by mechanical or fluid agitation', and theresultant products, containing some nutrientmedium, withdrawn through line 49. The medium and productl are separated'in separator 5I and the medium,Y if reusable, returned through line 46; Otherwise it is discharged through line 53.

rWhen using a batch process, a complete charge of medium will have tobe charged through line 48 with each batch of shale. This Acharge of me'- dium need'not necessarily be all fresh medium since the 'medium discharged vfrom the reactor With the( shale may bey recovered and reused'as well as any portion of 'product dischargedwithV the exhausted shale.

In practicing the invention as described in connection with Figs. 1 and 2 wherein in some cases the kerogen or its products may not separate as desired so that they can be Withdrawn from the reactors, the shale, after subjection to the microorganisms, may be treated either in the v,reactor or after discharge therefrom with a suitable vsol- Vent to vextract the kerogen and the Yproducts thereof, the solution being'subsequently processed in well-known manner to recover the solvent and the desired products. Where the metabolized shale (the shale afterv its treatment with microorganisms) is treated in the reactor with the'solvent,'it is preferred that the nutrient medium be first removed,4 particularly where water-soluble solvents such as pyridine are used.

The solvent extraction step may be Vused where the kerogen is converted in large measure to liquid products or. where the kerogen vand any products thereof are'found to be in asolid phase even after the treatment with microorganisms.

It is also tob-eunderstood that the shale or like forma'tiofncan'be soprocessed in its original formation'in theground by injecting the inoculated nutrient in input wells and removing `the product through output wells. If desired, a solvent extracton step can' Vbeused'after the 'nifitrient medium."` Hoiveyerthis `process not 'as satisfactory aswhen the shale isnrst grourdto, iin-e particlesizes.' 'y 1, while the foregoing example 'is Vconcerned with shale it is to be understood'tha't theprocess is applicable as well to the separation of oil from so-called sands such as'those found in the Athabaska sands of northern Alberta, Canada, wherein it isrestimated that the oil bearing sands cover an area of from 10,000 to Y30,0100 square miles and contain approximately 1070 billion barrels of oil. Obviously f many-modifications andvariations of the invention as above set forth may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

I claim:

1. A method for treating kerogen-type oil shales for the purpose of facilitatingthe separation and recovery of hydrocarbon, bituminous substances and the like associated therewith. which comprises subjecting said materials to the action of microorganisms selected from the group consisting of Clostridium sporogenes, Clostridium histolyticicum, Clostridium Zentoputrescens, Pseudomonas fiuorescens and mixtures thereof, in the presence of a microbiological nutrient medium capable of supporting the metabolism of said microorganism.

2. The method according to claim 1 in which the microbiological nutrient medium has a pH in the approximate range of 5.5 to 8.

3. A method according to claim 1 inwhich a temperature in the approximate range of 20 to 45 C. is maintained during the action of the microorganisms on said kerogen-type oil shales.

4. A method for treating kerogen-type oil shales for the purpose of facilitating the separation and recovery of hydrocarbon, bituminous substances and the like associated therewith,

v ROBERT T. SANDERSON.Y

References cited in the fue of this patent UNITED sTATEs PATENTS Number Name Date 1,753,641 Beckman Apr. 8, 1930 2,413,278 Zobell Dec. 24, 1946 2,458,535 Shappirio. Jan. 11, 1949 OTHER REFERENCES Annual Rev. of Biochemistry, 1935, vol. 4, page 608.

Federal Register, April 4, 1947; 12 FR 2215, 2217-2226.

Deegan, Oil and Gas J., June 28, 1947, pp. V101 105.

Zobell, World Oil, August 25, 1947, pp. 36, 39-40.

Claims (1)

1. A METHOD FOR TREATING KEROGEN-TYPE OIL SHALES FOR THE PURPOSE OF FACILITATING THE SEPARATION AND RECOVERY OF HYDROCARBON, BITUMINOUS SUBSTANCES AND THE LIKE ASSOCIATED THEREWITH, WHICH COMPRISES SUBJECTING SAID MATERIALS TO THE ACTION OF MICROORGANISMS SELECTED FROM THE GROUP CONSISTING OF CLOSTRIDIUM SPOROGENES, CLOSTRIDIUM HISTOLYTICICUM, CLOSTRIDIUM LENTOPUTRESCENS, PSEUDOMONAS FLUORESCENS AND MIXTURES THEREOF, IN THE PRESENCE OF A MICROBIOLOGICAL NUTRIENT MEDIUM CAPABLE OF SUPPORTING THE METABOLISM OF SAID MICROORGANISM.

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