US1607240A - Process of distilling oil shales and the like - Google Patents

Description

Nov. 16,1926. 1,607,240

D. J. L. DAVIS ET AL PROCESS OF DISTILLING OIL SHALES AND THE LIKE 2 Sheets-Sheet. l

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Nov. 16 1926. 1,607,240

. D. J. DAvls ET AL PROCESS OF DISTILLING OIL SHALES AND THE LIKEl 2 Sheets-Sheet 2 Filed Sept'. 20. 1922 Pavs, Geo. W Wallace,

@Hotncq Patented Nov.` 16, 1926.,A

UNITED STATES PATENT OFFICE.

DAVID J'. Il.- DAVIS AND GEORGE W. WALLACE, OE NEW YORx, N. Y., AssIGNORs To s; E Co1rI1ANY,orI sAN FRANCISCO, CALIFORNIA, A CORPORATION OE DELAWARE PRoCEss OF DISTILLING OIL sHALEs AND THE LIKE.

Application led September 20, 1922. Serial No. 589,52.

Our invention relates to therecovery of oils .and` by-products from oil-shales, in which term we include all natural oil-bear-l ing minerals, and consists, morespecifically stated, in a continuous process of obtaining oils, nitrogenous compounds and other byproducts, from 'oil-shales aond 'other solid earthy materials, containing hydrocarbons and which yield oil when subjected to either destructive distillation or simply to heat.

. ,Heretofore this operation has usually been an intermittent one performed in a closed chamber or retort heated externally.

In the process according to our invention, in. contradistinction to the previous practice, internal heat is utilized forythe distillation, as by the direct combustion of a portion of the combustible substances present inthe material being treated, which is constantly fed 4into the lower end ofthe chamber and upwardly through the same. It is not'material to the present invention in what manner or`by what meansthe zone of heat is `initiated and maintained, y(this step of the process being in itself old and disclosed, for example, in the patent to Dundas and Howes, No. 1,469,628, issued Oct. 2, 1923 tol Athe assignee of thepresent application,)

since the essential features of our invention are the maintenance, in oany way, of la stationaryfzone of heat at or near the top of a distilling chamber, and the continuous upward feed of the material being treated into and through said zone.

In the practice of our invention, We pro-.-

pose to proceed as follows: 4

A closed chamber is filled with the shale or similar material to be treated, a zone of I heat is initiated on the top of this charge,

air for combustion is passed downwardly through the charge, which is constantly renewe byl fresh raw material being fed progressively upwardly through the' chamber by means of a mechanical stoker, screw conveyor, o1N other suitable power apparatus. As soon as the fire is kindled on top of the charge, combustion' begins to take place 'in theshale itself and proceeds downwardly until a zone of combustion is formed, which shortly assumes a certain thickness and a certain distance from the top ofthe material in the-chamber, both thickness and distance being controllable at will by regulating or modifying the air and by varying vthe rate of feed of the material. The heat, generated in the said zoneof combustion and drawn downwardly through the material by the current'of air, sets up destructive distillation reactions .in the upcoming material, which result in the formation of oil, leaving in the residue, from which all of the volatile hydrocarbons have been removed, a certain amount Of'fxed carbon. 'This residue, containing fixed carbon, is continuously being advanced upwardly intoV the zone of combustion, where-it isburned, land normally supplies enough heat to the 'incoming material to bring about the required `decomposition reactions therein, resulting in the formation of the desired oils. It is evident that, where enough free carbon does not ex- .ist to furnish the required amount of heat,

aportion of the hydrocarbon material itself will be burned.

In the case of materials carrying free oil, the heat, carried downwardly through the material'from the zone of combustion by the content of the lgaseous Aproducts of combustion,'will vola- ,tilize the contained oil. In the majority of materials, however, destructive. distillation -occurs and the resulting Oil is a decomposition product of the complex solid hydrocarbons existing in the material, Means are provided for the removal of the residue from the top of the charge as fast as it is fed up.

Y In practicing our process, it is essential to be able to .control the temperature, location and extent of the zone of combustion, so as to vary the intensity and quantity of the heat transmitted to the raw material being lfed up towards said zone, thereby preventing the formation of objectionable clinkers and the. destruction of the hydrocarbon oils initially formed.A This control is obtained by varying the rate of upward feed of the material and bydiminishing the percentage -of' oxygen in the mediumof-.combustiom either by returninga percentage of the gaseous products of combustion, which leave the cham'- ber, to the incomingair, or by admitting a lolo percentage of water vapor or other inert gas l Where the shale, or. material being treated, contains a sufficient amount of nltrogenous matter, steam lis theA preferred medium of control as, when steam is used, an increased.l uantity of ammonlum compounds -wlll be ormed. 4TheI degree to which' the-'air used ,with the air"l used to support combustion.

treated; in many cases no modification is required.

There are many advantages accruing from the use of our process which willy now be evident to one skilled'in the art. In addition to the low initial and operating cost of the apparatus used to practice the process,

"therefrom, which assists in elevating the material to its decomposition temperature, as it approaches the zoneof combustion.

In the accompanying two sheets of drawing, we have illustrated, by way of example, one form of apparatus by which our process can be carried out commercially, although 'we lwish it to'be distinctly understood that we are in no way limited to the precise form of apparatus shown and that the process is capable of being performed in other apparatus. For instance, the chamber may be inclined instead of vertical, as represented in the drawings, in which,

Fig. 1 is a side elevation of the apparatus, a portion of the chamber wall being broken away.

Fig. 2 1s a plaii sectional view of the same l 1ty necessary, to describe here the apparatus,

i on line 2-2 of Fig. 3, and

Fig. 3 is a vertical central section through the upper part of the chamber.

In the example illustrated in these views, the closedchamber 1, in which the material lis treated, issupported ina vertical position, by columns 2, and consists of a cylindrical section 3 at the top, a conical section 4 below said cylindrical section, and a curved tapering section .15 `leading into the bottom of said conical section, the other -end of'said curved section having its axis horizontal and constituting the feed inlet for the raw material. The top of section 3 is surrounded by a trough 46 and the chamber is closed by a cover 7. A down-spout .8 for the spent material leads awayjfrom anopening in the bottom of said trough. On a central shaft10, drivenby the bevel gear drive 11, -are carried the scraper arms 12, on the ends ofwhich are blades 13, traveling in theA trough 6. From the horizontal end of section 5, a suitably trapped outlet pipe 14 for the oils leads downward, and to the face of said end is securedthe feed casing 15, containing a reciprocator piston 16, or other suitable means for fee ing the material .upwardly through the chamber 1.

The axis ofthe casing 15 is somewhatabove that of the horizontal end of section 5, so that the incoming material will not interfere with the escape of t'he oils through the outlet pipe 14. The raw material is supplied to the casing 15, for example, from a closed bin 18. An inlet 19 is provided through the cover 7 for the air and other gases and a suction blower may be connected to the outlet 21 below the bin 18 to create a partial vacuum in the apparatus to draw the air, etc, downward throughthe material, or the air may be forced into the chamberand the pressure in the same be maintained above atmospheric, if desired, instead of using suction and a pressure below atmospheric. The vapors, which are not condensed by their passage through the raw material in the chamber, are preferably drawn off through said outlet 21, but may be drawn off through the pipe 20,

4through which the bin 18 is filled, so as to which forms the subject-matter of application Serial No. 589,353, led ofeven date herewith, in detail,l since it is desireditos merely illustrate one means which may be employed to carry out the process, the operation of which will be readily understood `A fromk the above description.. As f before stated, the reactions which take place in the operation of our process are in no way different as far as we are aware, from those which take place in the Dundas and Howes process of Patent No. 1,469,628, aforesaid, and the regulation and modification of the air and the rate of upward feed of the material are controlled as the conditions obtaining, and results desired, at any given time, required.

Having thus described our invention', what we claim is' I 1. The roce'ssv of distilling oil shale, which consists in feeding a' column of shale upwardly through a closed chamber, creating a zone of combustion in the shale at the top of said chamber, passing air downwardly into said zone to maintain it and toproduce a zone of distillation immediately below said zone of combustion, and

continuously removing the spent shale from the top of said chamben 2. The process of dstilling oil shale, which consists in progressively feeding a column of shale upwardly through a closed chamber, creating a zone of combustion in' the shale at the top of said chamber, passing air downwardly into said zone to maintain it and to produce a zone of distillation l0 immediately beneath it, continuously removing the distilled oils andwapors 4from the 4 bottom of the chamber and the spent shale from the top thereof, and modifying the oxidizing el'ects of the air introduced by adding products of combustion thereto.

In testimony whereof We have hereunto set our hands.

DAVID J. L. DAVIS. GEORGE W. WALLACE.

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