US1643446A - Process for treating petroleum hydrocarbons - Google Patents

Description

sept. 27, 1927.l 1643'446,

W. M. CROSS 'PROCESS FOR TREATING PETROLEUM HYDROCARBONS Filed Au. 13. 1924 v Pff/01mg EMM/wm? EN TOR.

A TTORNE Y.

Patented Sept. 27, `192'?.

y 1,e'43,44.6` UNITED sTATEs PATENT OFFICE."

WALTER M. CROSS, 0F KANSAS GITY, MISSOR, ASSIGNOR TO GASOLINE PRODUCTS COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK. I

PROCESS FOR TREATING PETROLEUM HYDROCARBONS.

' Application led August 13, 1924. Serial No. 731,749.

This invention relates, to improvementsin la process for treating petroleum hydrocarbons, and refers more particularly to a process in which petroleum oils are converted from oils of a relatively high boiling point to oils of a lowcrboiling oint and having the characteristics of gasoline and the like.

This invention is a modification of an in-` vention disclosed in a, prior application, Serial No. 701,283, filed March 24, 1924.

Among the salient objects of the invention are, to provide a process in which the oil undergoing conversion is subjected to temperature and pressure conditions. regulated to effect the conversion while the oil 1s maintained substantially in the liquid phase; to provide a process in which the oil is preferably treated continuously, but con,- verted from the charging stock to what is termed as a synthetic crude containing increased quantities of low boiling point hydrocarbons relative to the low boiling point fractions contained in the original charging stock; to provide a process in which the hot synthetic crude is introduced to a. stage of reduced pressure while in a highly heated condition whereby the li hter fractions are immediately distilled o due to the contained heat in the oil; to provide a Aprocess in which water vapors or4 steam, preferably in a superheated condition, are introduced or injected in the oil either in the distillation stage or as they enter the distillation stage whereby vaporization is promoted and a sweeter product results.

The sing-le ligure is a diagrammatic side elevational view of the apparatus with parts shown in section.

Referring to the drawing, at 1 is shown a furnace in the upper part of which is posi# tioned a preheating coil v2 and in the lower portion Ia second bank of tubes comprising a second heating coil 3. These banks of tubes are connected b a transfer line 4. The furnace is preferably heated by. means of gas burners not shown, the combustion gases passing upward around the tubes andv passing oil' through the stackl 5. Six (6) is a reactiongchambcr connected by a translfer, line 7 to the discharge end of the lower bank of tubes. An evaporator is shown at 8 connected by a vapor line 49 to the refluxin tower 10 which is preferably of the bu ble ytower type, whlle a liquid transfer line 11 connectsthe evaporator Awith the-1e 'furnishing a means for introducin bottoms or fuel oil respectively. A tank 20 .l is interposed in adrawoii' line 21 from the reuxing tower 10.

The process is similar in operation to that explamed 1n some of my previous applications, and particularly in my application e Serial No. 629,723, filed April 3, 1923and Serial No. 701,283 filed March 24, 1924. It differs, however, from the latter case in that instead of introducing or injectinga blending oil into the transfer line I prefer to introduce at this point, or into the eva orating tower directly, a jet of superheatecl'steam.

Descrlbmg briey the process operated, oil 1s introduced from the charging tank 18 through the line 22 and forced by means of the pump 23 through the upper preheating coil 2 and lower heating coil 3 in the furnace 1. After passing through the lower coil, the oil has been sufliciently heated to be in the state of incipient conversion, that is, the oil has been sufficiently heated to bring it to a cracking temperature while it has not had suliicient time for the conversion to be consummated. In this state, while v the oil is at a cracking temperature, snbstantlal conversion has -nottaken place as this condition would be aocomfpanied' by the separation and deposition o considerable quantities of free carbon. Inoperating the process it is endeavored to eliminate this deposition of 4carbon in the heating tubes while at the same time supplying suiicient heat to the oil to cause the conversion to be completed in the reaction chamber 6 to which it ispassed through the line 7. f i

In the reaction chamber the highly heated oil is collected in a considerable body and moves slowly therethrough allowing sulficient time factor for the cracking reactionto be completed therein. As stated, the pressure and temperature conditions are so regulated that the oil preferably is converted while being maintained substantially line 11 and passed directly into the evapo-V rating tower 8 through a pressure reducing valve 12. -With the reduction of pressure and due to the" contained heat of the oil, im-

mediately on introduction to the tower there 'is distilled off from the o il body al substautial portion thereof inthe form of light volatile fractions which rise through the top of the tower into the line 9 and are introi duced? into the bottom of the dephlemating reaching the top of in the condenser i oline storage'tank" 17 while .the

or reiiuxing tower 10. The unvaporized products collect in the bottomof the eva orator and are withdrawn automatically y the manipulation of the valve 24 functioned by means of a liquidlevel regulating device .dlagrammatieally shown at 25. These boti toms are passed througlrt-he drawoff line 26 to a cooling Acoil -27 positioned in the condenser box 15 and are passed thence through the line 28 [to the fuel oil storage tank 19. The. overhead material introduced into the bottom:l of the bubble tower rises therethrough, percolating through a series of liquidoi ools which serve to separate out the higher boiling point fractions. The particular construction of this bubble tower forms no part ofthe present invention, as it 1s well known in the art.

The incondensible rtion of the vapors tgz bubble tower or reuxing column pass off through the vapor line 29 and are subjected to a condensing action in a. coil dia ammatically shown at 30 l(li-ox, 15. The liquid distillate condensed from these vapors is collected in a assepara'tor 16 from `which the liquld distillate'is removed through a line 31 controlled by a valve 3 2 and directed to the gasvases pass off through the pipe 33 controlled zby a valve 34 and may he utilized as fuel in the furnace during operation oriorother fuel pur- ,It (may, if desired, be treated for certain light fractions that were not separated out in the gas separator, as this gas 1s of a relatively rich,ch: l;racter.

The reflux condensate, separated out 'l the bubble' Vtower which is gravitated down- Wardly and in an opposite direction of the va rs, collectsin t e bottom ofthe tower to time through the valve 35i automatically vfunctioned by means ofthe' liquid level regulating device,36 identical in lts op'eration to that shown at 25. A valve 37, interposed in the drawoi` line 38, furnishes a means for directing the condensate vthroug'gh n is automatically drawn'oi from time nera-14e cled directly tothe cracking unit throughs.v

pipe 42 controlled by a valve 43,-this pipe having communication directly with e chargin the suction side of the charging pump 23.

The process is designed for continuous operation, the oil being introduced to the heatmg unit from the charging stock tank while selected portions of the refluxed material is retiyl'lcled 1f desired.

line 22 which communicates with to the transfer line through the pipe' 13 or directly into 'the bottom of theevapora.-

tor, if desired, is injected quantities of suf' perheated steam for the purpose 'of promotmg the distillation of the oil in the evapora-. tor, driving oli 'from the oil body a sweeter product than would result from distillation due solely from the vheat contained in the 'oiL The advantagesof steam distillation are well known in the art, in producng'a high quality and sweeter distillate than that obtainedby direotheating. It is thought to be novel, however, to crack the oil in a liquid phase and utilize the contained heat'by distilling oli the lighter fractions and during this distillation inJecting superheated steamv and,A further, the amount of free Carbon conf l tainedther'ein is considerably lessened.

I claim as my invention:

A process for treating petroleum hydrocarbons comprising raising the oil to a crack'- temperature in a heating stage, collect nig all the oil'to be treated in a reaction "stage while maintaining temperature and pressure conditions adapted to `elect 'conversion while the oil is :substantiallyfin'the liquid Phase, withdrawing ll f-llebeiersioe productsy from tlievi-eaction stageinria-irelativelyrsmall releasing thepressure on the'streamand'ihjecting into lthe floo j flowing thenhixture of s bil. and steam toa'nenlarged zone manlighterfractions o the converted roducts M. OSS,-

lio be more readily pumped through pipe lines, Y

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