US1400800A - Art of cracking hydrocarbons - Google Patents

Description

JR. l

Am oF @meme HYnRocARBoNs.

Patented Deu. 20, 192k J. vv. C0AT APPLICATION FILED SEPT. 27,1917. AUQ,

aonn'w. consi', an.; 'or ricrea. carencias, nsfsrenon nurse, onnenonra, n eonronerron A enr or caserme nrnnoeannons.

To all 'whom' it may concern.'

Beit known' that I, JoHN W. Consi', J r., a citizen of the United States of' America, a resident of rlulsa, in the county' of rlulsa, State of" Oklahoma, have invented certain newand useful Improvements Vin the Art of Cracking Hydrocarbons, of which the following is a full, clear, Vand exact description, referencebeing had to the accompanying drawing, forming a part of specifica tion.

'lhis invention relates to improvements in theart of cracking andotherwise treating hydrocarbons, the object being to avoid the losses which have heretofore been incurred by evaporation during the operations of reining cracked hydrocarbon products.

.ln following the ordinary ractice, theA vapor passing from a crackin'gfstill is condensed under a high pressure, or under a pressure of at least one atmosphere. High pressure in the condenser has =been"consid ered desirable for the reason that .under .a relatively low pressure, the lightest fractions in the vapor will 1pass away in the form of gas'. These volati e able constituents of the cracked product, but it is quite diiiicult to retain them in' a liquid state.l So the condenser. `o'f the ordinary cracking apparatus is usually maintained under a very high pressure for the pli ose of liquefying these light fractions. n this connection, it is high-.lyimprtant to .observe thatthe object is toeventually utilize the light hydrocarbonsin aliquid state. lf

condensation under pressure-does not 'result in the preservation of the very volatile fractions foi-...comercial usein. a liquidstate,

it fails to accomplish the'd'esired results-'Alfthough vthe ofhigh'pressure inthe condenserV is; strongly advocated by experts .in

lthis art, .and Irealizingthat such pressure is now used iii-most -successfulrandf'highly de- .veloped crackingapparatus', ll. .'believe; that condensation under Thigh pressure .andthe subsequent treatment of they product resultsina loss, instead-of algain,.ofthevolatile fractions.' For theffollowing reasons, ll pre'- fer vto crack. Vthe hydrocarbons underv a highpressure, and to condense the cracked prod.'

fuctinavacuum.

To subject the hydrocarbons to a-high tein-m -pe'rature lwhilein a llquld .state,1t .is,' of" course, desirable to maintain the contents ,ofl the stillunder ahigh pressure, and -if th1s v'pressure is maintained' in the condenser a g carry away other very fractions. are most valu#l able manner, so as to Figure' .Specicationof Letters Patent. i 'Pwbmtggd Ime@ @c1179 ggjlp Application led September 257,191?. Serial No. 193,473. i l

ro 'rnn rnocnss confirm, Orf-'Ii large` volume of highly desirable volatile fractions pass lfrom the apparatus ina liquid condition.-V However, it must. be understood -that thel cracked product passing lfromthe"'condenser is not 1n condition.for

would 'otherwise-.remain in coveig of very .volatile hydrocarbons which woul .otherwise pass from the condenser .1in the vform `ofso'as, but when .the 'productie undergoing su equent treatment, t-,hes'e'lightv into.

fractions escape the liquid. As a consequence, the factual vyield of gasolene is greatly reducedby the -loss of the lightest fractions whichaescape during the treatmentof thecra'cked product,

and also by. the los's'of heavier'hydrocarbons carrying with thein a large' volatlle v but "very valuable other words condensation.

7o" the temporary re.-

"15 the atmospheref'and f i valuable'v portions of Y' which pass away with thelighter fractions. f

To avoid all'of these hydro-carbone, underpressure in any suitproduce a 'vapor' con'- taining the relatively 1owlboilingpoint fractions, but instead 'pf condensing. the vapor under a high pressure, I 'preferably maintain a vacuum in the' condenser, ,therebypreventing the mostyolatile fractions from passing outv 'in-a, liquidjsta'te. l v'llhe product', therefore, includes a liquid that 'can .sulted from the, evaporation of a -be treatedfo'r commerci'alpurpo'ses withoutv g incurring the `losses that haveheretofore -rei large, voL lime ofthe. volatile fractions. 'll-he, light fractions, passing from the'- condenser. 'in the 'form of gas,'* lare j liqueiied' 4inany suitable' ,mannen and blended with a-heavierhydro new'method. A. Fig. lll is an "enlarged-vergcal'sectlon of the absorption chamber.

To illustrate :the -invention lIlfhave. shown 1d to produce acommercially val'-` uable' hydrocarbon vin ixture. -These' ASligihtf and v blended any pressure lower ilarge volume of the lightest scribed.

i a cylindrical cracking about 600 still l arranged above a heating chamber 2 and 4connected, `by

means of an' air cooled vapor pipe 3, to a relinx condenser 4. 5 designates a vapor pipe. leading from the reflux condenser to Aa main condensi coil 6, from which the cracked distillate is conducted through a pipe 7 and into a receiving tank 8.

- The cracking apparatus is particularly adapted for use in 'cracking high boiling point products of distillation such, for example,

The oil to be treated-is introduced into the cracking still in any suitable manner, and any desired pressure may be obtained by regulating a valve 9, preferably located in the vapor pipe 5. The pressure in the still, vapor pipe 3, and reflux condenser 4, is preferably greater than 50 pounds per square inch, for example, about 80 pounds per square inch, and the temperatureof the contents of the still preferably ranges from F. to about 8009 F. If the pres sure regulating valve 9 is arranged in the vapor line as herein shown, the contents of the still can be maintained under the desired high pressure, and a vacuum may be maintained in the condenser 6. The hydrocarbons are preferably cracked under pressure and condensed in a vacuum. The term vacuum as herein used is intended to cover than the normal atmospheric gpressure, and does not necessarily mean an absolute or perfect vacuum.

y l() designates a gas conductor leading from the condensate pipe 7 to a vacuum pump 12, and 13 is a gas conductor leading from the receiving tank 8fto the vacuum pump. The conductors 10 and 13 are prvided with valves 14 and 15 respectively. When the apparatus is in operation, one or both of the valves 14 and 15 are open, and the vacuum pump 12 is actuated to maintain a vacuum in the condenser 6 and receiving tank 8.- The cracked distillate is thus subjected to a vacuum, and as a. result, a

and most volatile fractions pass through the gas conductors 10 and 13, to the vacuum pump 12. It is to be understood that the invention is not limited to the production of a-vacuum in the precise manner herein shown, ject being to collect the lightest andmost volatile fractions from the cracked distil late, before the latter is subjected to the relining operations.

The gas passin from the vacuum pump, is preferably blen ed with a hydrocarbon oil under pressure, as will be hereinafter de- The cracked distillate discharged into the receiving tank 8, may be rened in any suitable manner. To illustrate a vsuitable rening apparatus, I have shown a tank lwhereby' it is forced into the tank 16.

as the distillates or residues result-4 ing from the distillation of crude petroleum.

the vmain ob-l 16, wherein the distillate may be agitated and' treated withacidl as is well understood in the art, and a steam still 17 for distilling the. hydrocarbons passing from the tank 16. The oracked'distillate passing from the tank 8, Hows through a` pipe 18 to a pum ft319 undergoi the agitation and acid treatment vin the ta 16, t e -distillate' is discharged through a p pe 20 to a pump 21 which foices it into a steam still 17. The vapor passing from the steam still, liows through a pipe 26 to.- av condenser 27, and the refined distillate is discharged through a pipe 28 to a tank 29.

' Prior to this invention, the vapor passing from cracking-.stills has 4been condensed unfore, included a large percentage of very light volatile fractions., easily retained in a liquid state. In the following ordinary practicesuch condensate, including the very li ht fractions, is usually agitated, distillati dled in such 'a' manner 34 to a gas comwhich cannot be and otherwise han` yder pressure, and the condensate has, there-` that very large volumes ofthemost volatile fractions esca e in a pipe 32 to an absorption. tank 33.. passing from` the vacuum pump 12 37 is provided with a perforated discharge member 38 located near the bottom of the absorption tank Some of the compressed s is liquefied in thev coolin coil 36 and t e remaining lgaseous fractions are vdischarged through thnerforated member 38 in the absorption t rThe refined oil is pumped' from the tank. 29 to the absorption tank 33, as `previously" b ody of this oil is maintained in the absorptionptank. 39- designates -a gas conductor leading from the top of the absorption tank, and 40designatesa conductor through which the liquid is discharged from the absorption 'tank to a storage tank 41. .Valves 42 and 43, in the conductors 39 and 40, are adjusted to Amaintainthe contents of the absorption tank under a pressure of, preferably about 150 pounds per square inch. The compressed gas bubbling up from the discharge member 38, commingles with the refined distillate while the contents of the abso tion -tank are maintained .under-pressure, an under these conditions ajve large percentage of the light hydrocarbon actionsin the s will be read' y absorbed by the refined is' pointed out, and a tillate.I The permanent gas, or unabsorbed gas, passes out through the conductor 39, and the refined distillate blended with very light volatile fractions, pass out through the conductor 40 and into the storage tank 41. This tank contains the light fractions, taken from the cracked distillate, and restored in the absorption tank after the distillate has passed through the refining apparatus.

I claim In the art of making gasolene, the method which comprises crackin and, distilling hydrocarbons, subjecting t e resultant distillate to a vacuum so as to Withdraw the lightest and most volatile fractions in the form of gas, thereafter refining the distillate, and subsequently returning said gas to the refined distillate by commingling the gas with said distillate and maintaming thefmixture under pressure so as to blend the rened hydrocarbons With the lighter and more volatile fractions.

In testimony that l claim the foregoing ll hereunto aflix my signature.

roi-1N Wjoons'r, JR.

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