US1474147A - Distilling and cracking petroleum - Google Patents

Description

Naw, E130 J. L. GRM

DISTILLING AND GRACKING PETROLEUM Filed Oct. 25, 1918 4 Sheets-Shee l Mila-M7 Nw, mi, w23,

J. L. @mv

DISTILLING AND CRAGKING PETROLEUM Filed 0G13.4 25 l9l8 DISTILLING AND CRACKING PETROLEUM .Filed Oct. 25, 1918 4 Sheets-Sheet 5 ma ma DISTILLING AND CRACKING PETROLEUM Fild oct. 25, 1918 4 sheets-sheet 4 liatented,Novo t3, i923.

'on-iran sTaTes eaTisnT errance,

JOHN LTHROP GRAY, OF ELIZABETH, NEW JERSEY.

DIS'J'JILLING AND CRACKING PETROLEUM.

Application led October` 25, 1918. Serial No. 259,649.

T all whom t may concern.'

Be it known that I, JOHN LArHRor GRAY, -a citizen of the United States, residing at Elizabeth, in the county of Union, State ot' New Jersey, have invented certain new and useful Improvements in Distilling and Cracking Petroleum; and I do hereby de.

i .l5 larly designed t0 permit the continuous distillation oit heavy residuals and crude oils to kcoke at a relatively low cost, both with respect to the initial expense ot the installation and the etliciency and economy of maintaining and operating it.

The invention is particularly applicable i `to the treatment of Mexican crude oil or like crude oil containing relatively large proportions of sulfur, inasmuch as the process `involves the obtaining of a product whereih the sulfur content is` reduced to the low minimum tolerated for use -in v'a fuel oil in the firing ot marine boilers and thelike. By the practice ot the process it is possible to vobtain in a single and continuous operation from these crude oils, heavily charged with sulfur. a correspondingly refined distillate, and a'residual coke having a fuel value which largely contributes to the industrial ,35 and economical availability of the process for widely extended use.

The nature and scope of the invention will be more fully understood by reference to the accompanying drawings. which illustrate aJ form of apparatus adapted for its successful practice.

ln the drawings.- Fig. l represents a longitudinal vertical section of the apparatus, partly in elevation g Fig. 2 represents a horizontal section thereottaken on a plane indicated by the line 2 2 ot' Fig. l; Fig. 3 represents a vertical section taken on a plane indicated by the line 3-3 ot Fig. 1.

Fig. 4 represents in perspective, the piping system tor the supply ot the oil to the individual members of the distilling unit l and certain auxiliary heating and cooling devices incident to the practice of the invention;

Fig. 5 represents on a larger scale, a sectional elevation ot the lower portion of one of the distilling elements with its Oil supplying and cooling devices.

Similar numerals of reference indicate similar parts throughout the several views.

Ketel-ring to the drawings, indicates a furnace chamber provided with any suitable torm of tire-box and ash pit 5, for the maintenance of a sufficient heat for the distilling andcracking operation. A furnace stack G provided with a regulating damper 7' controls the furnace drift and permits the operator to establish and maintain the necessary heating conditions. course, be understood that the particular furnace illustrated is but typical of many others that might be employed for the same purpose; that is to say, to heat the distilling and cracking apparatus now to be described.

The distilling and cracking apparatus consists of a unit which` in fthe particular embodiment shown in the drawing, is made up of a series of upright tubes S, united at the top by a common header 9. This header discharges by an elbow pipe l0 into an up? right drum ll which serves as a receptacle Jfor the coke produced as a residum in the process and `also as a collecting and transmitting drum for the gaseous or vaporous products ot' the distillation on their way to the condenser. The still and also the condenser may, if desired` be maintained under pressure so as to assist in the cracking of the vapors and their liquefaction.

The main orleading characteristic of the invention consists in the employmentwithin the upright tubes 8V ot a filling, adapted to become liquid upon thc application ot heat` and through which the crude oil or the like to be distilled and coked is caused to pass. The filling preferred Yt'or this purpose is lead, or its equivalent. introduced in a molten state into the individual pipes 8 through suitable pouring openings in the header at points immediately above the upper ends of the tubes, which openings are adapted to be thereafter closed by means of screw plugs 12 or the like.

The lower` end-cap 30 of each individual It will, of`

el, amarrar tube 8 is adapted to rest within a base plate 31, and each tube is provided with a'plug 13 A eter, as shown.

shown in detail in Fig. 5. The upper screwthreaded end 14 of this plug engages a corresponding interior screw thread of the end cap 30, and the plug itself is provided with a centralvbore 15 of relatively small diam- The individual plugs 13 exter' "l into the open air space 16 outside or" the i'urnace chamber and are thus exposed to the cooling influence of the air;. so that, when the molten lead, or the like, is poured into the individual upright tubes 8 and'enters the narrow bore 15 of the plugs, it will tend to chill in said bore so as to solidify therein and preventtlie running out of the -lead during the operation of filling the individual tubes 8. The promptness with which this chilling takes place is further insured by means of cooling;r jets 27 supplied from a water supply pipe 32 (see Fig. 4), and in such position with respect to the bored plugs that the jets will direct sprays of cold water or the like upon the bored plugs when desired.

. So also, means are provided, as represented, for instance, by the oil jet burner 25 to direct a heating llame on t-he bored plugs 13, of such a character as to promptly bring the chilled lead therein to fusion when desired. The operator, therefore, is enabled, at will, either to, bring the lead wit-hin the bored passages of the plugs 13 into fusion or to congeal the lead in said passages.

The lower screw-threaded end of each individual plug is connected by a branch pipe 18 with amain supply pipe 19 Jfor the crude oil conveyed to the several tubes 8 of the distilling and cracking unit, ln each of these branch pipes is arranged a suitable meter 2O provided with a by-pass 21, and

appropriate valves, as indicated at 22, are provided for determiningthe flow through the meter and by-pass or to cut the one or the other out of the circuit altogether.

The main pipe 24 for conveying the oil to the individual bored plugs of the upright tubes 8 is connected to a superheater of some appropriate kind. As indicated in Figs. 1 and 2, the general structure, for this purpose, includes, in addition to the heating chamber 4, a heating chamber 40 communicating with the common stack 6. This heating chamber 40 is traversed by a pipe system 41 for preheating the oil supplied to the pipe 24; and, connected with this system is the pump 42. From each of the individual branch pipes 23, return pipes 26 connect with the return branch 24L1 of the main 24, and to this return main there is likewise connected the supply pipe 43 leading from the source of oil storage and which, together with the returnbranch 24EL connects with the suction side of the pump. t

In the practice of the invention, when the several upright tubes 8 have received 4(up to or nearly up to the header 9) their filling of molten lead, a portion of which is congealed in the bored passages 15 of the plugs 13, a condition of pressurepis created in the system,1by means vof the pump. Thereupon, the water jets having been turned oid and the heating flame applied to the several plugs 13, the congealed lead in the bored passages of the individual plugs is brought to fusion. As soon as the lead inthe bored passagesihas been brought to full' fusion,

the preheated crude oil, by reason of the pressure prevailing in the system is forced upwardly through said passages into the up right tubes 8, and passes into the columns ot molten lead contained therein, the pressure employed being sufficient to keep the passages of the several plugs clear ot lead. ln its upwardA passage through the columns of lead contained in the uprighttubes 8, the crude oil is distilled, with the formation ot coke which enters the header 9, and is continuously or intermittently blown by a steam jet or the like 48 into the upright drum 11. At the same time,the distillation of the crude oil is accompanied by its partial or complete desulfurization, according to the character of the molten material employed in the tubes 8. The gaseous or vaporous products of distillation pass into the drum 11 and on into the condenser (not shown) bythe pipe 29. By the employment of a suitable loaded valve on either the inlet or the outlet side of the condenser, a back pressure will be produced determining the degree to which the products of distillation are cracked.

lt will be understood that, quite aside from any desult'urizing function of the molten lead by chemical combination with the sulfur of the crude oil, the vaporization and gasification incident to the distilling operation them-l selves eliect in part a separation of the sul- W fur, and, the sulfur or sulfur compounds thus separated are condensed in large part in the drum 11 instead of passing on to the condenser. The desulurizing of the crude oil is therefore due to the combined action of the lead in the formation of lead-sulfur compounds, to the extent to which such compounds are produced, and to the dissociating eli'ect (upon the sulfur and sulfur compounds contained in the oil,) of the heat ot parare? to chemicall unite with sulfur. Where lead is employe however, and when for any reason it is desired to regenerate the lead so as to restore it to its ori inal metal condition, this may be accompllshed either in situ by blowing air upward through the lead,`

after disconnectin the elbow pipe ll() from the drum 11, thus merizing the lead, or by removing the lead from the tubes 8 in any suitable way (as, for instance, by disconnecting the plugs 13) and permitting the contents of the severaltubes to How into an appropriate bessemerizing receptacle and blowing air through the lead thus collected until the sulfur has been. driven oitto ,the

taining with a relatively small quantity of the lead or other like molten material an extensive heating surface and practically the maximum tr'avel of oil through the molten material. This insures the complete distillation of the oil to coke.l and the corresponding release of the sulfur from the oil,

which, as I have already pointed out, to a very large extent. due to the thermal conditions of the distillation and due entirely thereto when the molten material employed does not combine chemically with the sulfur. which is not always the case even when llead is employed as a molten material. Furthermore, the employment of the upright tube header system characteristic of the invention, has advantage over the employment of lead or the like in an ordinary horizontal cylindrical still for the reason that to suitably protect the heating surface of such a still by means of lead, would require the employment of a quantity of lead so large as to reduce the heating surface to a relatively small percentage or, in the alternative, would create a load in the still so great that the still would be distorted at the temperatures necessary to the distillation process; whereas, in the upright. header system of my invention, not only is the amount of lead employed reduced to a low minimum. but the element of still distortion is wholly absent.

So also, the employment of the upright tube header system provides a practical way for carrying-on the process continuousfor the complete continuous conversion of the entire body of crude oil into the gaseous or vaporous condition, with the dissociation of the sulfur and with the continuous production of coke, 'and particularly with the continuous removal of the coke, which floating to the surface of the molten material of higher specific gravity may be promptly expelled from the header into the receiving drum thereby keeping the distilling apparatus continuously disembarrassed of its presence.

Furthermore, in the practice of the invention, the employment of the bore or passage of relatively'small diameter through whichA the oil is injected into the upright tubes insures the passageof the oil therethrough with such relative velocity as to exclude the down-passage of the lead duringl the distilling operation, and nevertheless permits the sealing of the upright tubes by congealing of the lead withinthese almost capillary passages, as soon as the heating jets are extinguished and the chilling water spray or the like is applied. The operation of the apparatus is so sensitive in this regard that the passages 15 ot the plugs -will remain securely obstructed by the congealed lead therein until such time as the oil to be distilled reaches the temperature at which it is desired to begin to discharge it into the tubes 8, whereupon, by igniting the heating jets or burners, the lead in the restricted passages l5 will be brought into fusion so promptly that the oil under pressure will immediately clear the passages and will keep them open until the operator desires to shut down; whereupon. a lowering of the pressure on the oil feed, the turning off of the heating jets, and the turning on of the water sprays will, with similar promptness, congeal the lead as it starts down through the passages and securely close them until it `is necessary to start up again. This form ot control is particularly adapted to the purposes ofthe invention` inasmuch `as it dispenses with the employment of any form of check valve.

Inv the cracking' of oils, for the purposes of increasing their proportion of gasolene. it has heretofore been the uniform practice. insofar as I am aware. to employ as the still charge an oil which is itself the product ot distillation. To attempt to subject ordinary crude oil to a cracking' operation in such stills would result in the separating out and deposition upon the heating surfaces of such a quantity ot dirt and carbonaceous matter as would distort the stills. and. at the high pressures employed would cause their explosion. 0n the other hand. the employment of the apparatus ot the present invention, as a cracking unit for crude oil is entirely feasible, without danger. tor the reason that not only the carbonaceous matter, but the' dirt as well, is carried to the upper surface of the lead and is continuously removed, so that it interferes in no wise with the uniformity, regularity, and safety oi the operation.

As hereinbefore indicated, a striking merit of the invention is its capacity to distill Mexican crude oil to coke continuously, and, nevertheless, to produce a refined product, so low in sulfur that it makes a satisfactory fuel oil for marine boiler firing, fully meeting the naval specifications in that regard. All Mexican crude oil with which lf am familiar, contains more than 3% of su".- fur and 1s unsuitable for marine fuel oil,

' not only on account of its sulfur content,

but also on account of itsfhigh viscosity. When distilled in accordance with the present invention, the distillate is not only suitable for marine boiler firing, but can be used as a gas oil in vthe production of illuminating gas. and in oil refineries for the production of lubricating oils, gasolene, kerosene, and parafiin wax. The coke constituting the by-product of the operation 'may be readily briquetted and sold for fuel purposes, and the diminished weight of the distillate as compared with the original crude oil permits it to be shipped at a diminution in freight rates represented by the weight of the coke-removed in the distilling process, which frequently amounts to from 18 to 22%. It will, of course, be understood thatnot only the coke but any solid impurities carried up with it to the surface of the molten material and into the header will likewise be discharged into the receiving drum by the st eam jet or its equivalent. It is further to be ynoted that the receiving I drum'is to be maintained gas-tight during the distilling operation and capable of Withstanding whatever back pressure is set up in the system to produce the cracking effect desired.`

Referring further to thedesulfurizing of the lead, when such desulfurizing is required, it is preferred to carry it out in situ i. le., without removing the lead from the upright tubes 8. To this end, the heavyoil should be removed from the system by pumping in distillate until all of the heavy oil is displaced. Thereupon the distillate and the oil'vapors are blown out of the enmaaier pipe leading to the condenser for the distillate and may be removed either before or after passing through the condenser.

Having thus described my invention, what I claim is:

l. Apparatus for the refining of petroleum, comprising a series of upright tubes, said tubes being provided with a filling of molten material, injectors of relatively small bore forming extensions of the tubes, said injectors discharging petroleum into the lower ends of the tubes, against the pressure of the .molten material, and means for bringing into fusion any of the molten material that has congealed in the injectors; substantially as described.

2. Apparatus for the refining of petroleum, comprising a series of upright tubes, sa'id tubes being provided with afilling of molten materia-l, injectors for the petroleum, said injectors discharging into :the lower ends of the tubes a nd forming a continuation thereof of relatively small bore, means for congealing that part of the molten material that finds its way into the injectors, means for re-melting the congealed material, and means for creating a petroleum pressure in the system back of the several injectors so that on said re-melting of the petroleum will immediately rush into the injectors and on into the main body of molten material above; substantially as described.

3. Apparatus for the refining of petroleum, comprising a series of upright tubes, said tubes being provided with a filling of molten material, injectors for the petroleum, said injectors discharging into the lower ends of the tubes and forming a continuation thereof of relatively small bore, means for congealing that part of the molten material that finds its way into the injectors. means for ire-melting the congealed material, and means for creating a petroleum pressure in the system back of the several injectors so that on said remelting the petroleum will immediately rush into the injectors and on into the main body of molten material above, said pressure means consisting of a pump having a discharge main and a return main, the latter being also connected with the source of petroleum supply, and the Aseveral injectors being connected up by branch pipingin parallel across the said discharge and return mains; substantially as described.

f t. Apparatus for the refining of petroleum, comprising a series of upright tubes, said tubes being provided with a filling of molten material, injectorsA for the petroleum,` said injectors discharging into the lower ends of the tubes and forming a continuation thereof of relatively small bore, means forrongealing that part of the molten material that finds its way into the injectors, means for re-melting the congealed ma,- teria-l, and means for creating a petroleum llt) consi rial above, Said gressum means of a pump hwmg a dlscharge feuifi nam, the latter bing ais@

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