US1703550A - of chicago - Google Patents

Description

Feb. 26,1929. 1,703,550

w. F. sums APPARATUS FOR CONVERTING HYDROCARBONS Original Filed May 9. 1921 five/z? W66, Willis F." Sim! Patented Feb. 26, 1929.

UNITED STATES EATENT FFEQE.

WILLIS F. SIMS, OF CHICAGO, ILLINOIS, ASSIGNOR T UNIVERSAL OIL PRODUCTS COMPANY, OF CHICAGO, ILLINOIS, A CORPORATIGN OF SOUTH DAKOTA.

APPARATUS FOR CONVERTING- HYDROCARBONS.

Application filed May 9, 1921, Serial No. 487,896.

This invention relates to improvements in apparatus for converting hydrocarbons and refers more particularly to an apapratus for converting hydrocarbons of a relatively hi 1 boiling point to hydrocarbon oils havii boiling point substantially that of gasoline and the like.

llhis application is an improvement over a previous application filed by me, Serial 10 No. 445,599, filed February 17, 1921.

Among the salient objects of the invention are to provide an apparatus in which the vaporized portion of the oil which is volatilized in the expansion chamber is passed through dephlegmating means in which the oil vapors are subjected to successive stages of dephlegmation; to provide an apparatus in which after being so dephlegmated, the distillate may be. returned and circulated as a dephlegmating medium to the successsive stage of dephlegmation simultaneously therewith having a portion of its more volatile constituents relieved by the heat of the vapors; to provide an apparatus wherein by 5 adding regulated quantities of cool fresh oil to the dephlegmating stages in combination with the returned distillate, an accurate and positive control of the temperatures may be maintained in the dephlegmating zones; to provide an apparatus which is economical and one in which the oil may be treated continuously.

The single figure of the drawing, a side elevational view of the apparatus.

Referring in detail to the drawing the heating means 1, which may comprise either a system of tubes or a shell still, are charged with oil through the inlet pipe 2 controlled by a valve 3. This oil is supplied from any convenient source (not shown). The heating tubes are mounted in the furnace l, which is preferably heated by means of gas burners 5. The oil, after being raised to a cracking temperature in the heating tubes, is permitted to'vaporize in the expansion chamber 6, mounted above the heating coil and outside of the fire Zone. Means is provided for withdrawing the unvaporized oil from the reaction chamber 6, and is indicated at 6. As mentioned, the heating and vaporizing zones may be combined in the Renewed March 15, 19%.

vaporized oil rises through the vapor line 1 and is directed to the primary rectifier or heat interchanger 8. This rectifier or dephlegmator apparatus comprises two headers 8 and 8 connected by horizontally positioned tubes 8 The cracked vapors entermg the header 8 pass through the tubes to the header 8 from which they are directed through a transfer line 9 to a second rectifier or depl'ilegmating apparatus 10. This second heat inter-changer is identical in construction to the rectifier 8 having the headers 10 and 10 connected by intermediate connecting pipes 10. The pipes connecting the headers in the respective rectifiers are enclosed in the shell which contains liquid distillate returned from the receiver 11 to the rectifiers 10 and 8 connected in seies, the oil arst entering the rectiiim 10 through the line 12.

Toreturn to the passage of the dephlegmated oil vapors after leaving the header 10 of the second dephlegmating apparatus, the uncondensed portions of the vapors are directed through the line 13 to a water condenser 14; in which the coil pipe 15 is mounted. In this water coiulenser the vapors condensed and pass to the re ceiver 11. The receiver is equipped With the usual appurtenauces cons ting of a l quid. level. gauge, pressure relief pipe and liquid drawoil line. Near the bottom of the receiver is tapped the line 12 in which is interposed the valve 16. The distillate collected in the receiver is directed through the line 12 back to the dephlegmator 10 and is there introduced to the interior of the shell surrounding the connecting pipes 10 through an elongated longitudinally pos tioned perforated pipe 17. The distill will. rise in this shell to completely immerse the heated vapor conveying pipes and overflow through the line 18 into the bottom of the shell of the primary rectifier 8 through a similar perforated pipe 19. Liquid level gauges 20 are supplied on the periphery of the shells to desi nate at all times, the level of liquid oil in each unit. In this manner, by directing the heated oil vapors through be at a higher temperature.

a plurality of comparatively small pipes and immersing the pipes in the cooler distillate, it is possible to take advantage of the heat given off by the oil vapors while being dephlegmated to redistill the distillate, relieving therefrom the lighter oil constitucuts or fractions. More specifically, as the distillate returned from the receiver riscs about the heated pipes in the rectifier due to the high temperature of the vapors in the pipes 8 or 10, the oil surrounding the pipes will be subjected to a temperature which will redistill the distillate returned thereto from the receiver. The vapors released from the body of this returned distillate are drawn off through the vapor lines 21 and 22 and condensed and collected separately in suitable condensing apparatus (not shown).

It is understood, of course, that that portion of the oil which is not vaporized in the second rectifier 10 will flow through the line 18 and be subjected to a similar distilling action in the primary rectifier although the conditions of temperature will be increased in the latter rectifying zone due to the fact that the vapors passing therethrough will As explained, the vapors released from the distillate in the primary rectifier will pass off through the vapor line 22. The overflow or excess liquid distillate not vaporized in the primary rectifier is drawn off through the line 28, controlled by a valve 24 and returned through the pump 25, and lines 26 and 27 to the charging line 2. The condensate condensed from the vapors in the respective dephlegmating or rectifying elements is drawn off from the headers through secondary lines 28 controlled by valves 29, which connect to a header 30 through which the condensate is directed to a pipe 31 to the line 27. In the drawings, but two rectifiers have been shown but it is understood that a number of these dephlegmating units may be connected in series and the distilla e re turned through each successively. Distillation may be accentuated in the rectifier-s by injecting live steam through the pipes 32 controlled by valves "his alternative is not essential, however, to procure adequate evaporation of the distillate. In returning the distillate, from the receiver, the valve 16 is positioned in the return line to reduce the pressure on the distillate in order that the distillate in the rectifying or dephlegmating apparatus may be at substantially atmospheric pressure. 7

Further, it has been found that due to the fact of the temperature and limited quantity of the distillate, the control over the temperatures in the respective dephlegmating apparatus is somewhat restricted. Consequently, it has been found feasible to connect the distillate return line 12 with a secondary line 34, controlled by a valve 34 communicating with the charging line 2 and a similar line 36 controlled by a valve 35 communicating with the line 18 which transmits the distillate from the rectifier 10 to the rectifier 8. By introduction of regulated quantities of raw oil to either of the dephlegmating units through these lines and combining this raw oil with the returned distillate prior to its introduction to stated units a more accurate control is obtained over. the temperatures of the dephlegmating medium passing through the respective rectifier. This raw oil, in addition, adds somewhat to the quality of the distillate obtained from the vapors drawn from the respcctive dephlegmating units, due to the fact that it enters the zones in a relatively untreated state. This makeup oil is returned to the cracking tubes with the unvaporized portion of the distillate and is subjected to treatment with the raw oil charge.

An illustrative run of the process, using the described apparatus follows: Char-gin oil of approximately 81 degrees Baume gravity and heating the same to a temperature of 750 to 850 degrees F., directing the oil vapors released from the cracked oil body through successive: stages of dephlegmation and collecting the dephlegmated vapors as distillate after which the entire or a portion of said distillate may be returned to the dephlegmating stagesin reverse order, and using the distillate as a dephlegmating medium with regulated additions of raw oil, there has been obtained therefrom oil fractions of a gasoline-like character from the distillation in the second dephlegmating stage and a distillate approximately more closely a kerosene out having a Baum gravity of from l0 to 42 degrees from the dephlegmating stage having the higher temperature. By this process, it has been possible to isolate the incondensable gas and separate therefrom the more desirable fractions and byrdistilling this distillate in the dephlegmating zones, a relatively sweet, marketable product is produced inas much as the gasoline like fractions are distilled off while the heavier fractions remain in an unvaporized state and are returned for recraclring in the heating coil and expansion chamber, said incondensable gases being discharged through the valve controlled gas pipe leading from the receiver 11.

I claim as my invention:

An apparatus for cracking hydrocarbon oil, comprising a heating coil, a reacting chamber and a dephlegmating means, serially connected, means for condensing uncondensed vapors issuing from said dephlegmating means, means for collecting the resulting distillate, means for returning regulated quantities of the distillate to said dephlegmating means, to be subjected to redistillation while out of contact with vapors undergoing dephlegmation in said dephlegmating means, means for supplying incoming charging oil in regulated quantities to said dephlegmating means, to aid in maintaining a controlled temperature therein, means for Withdrawing unvapo-rized oil from said reaction chamber, and means for maintaining a lower pressure on the distillate undergoing re-distillation in said dephlegmating means than is maintained on the vapors undergoing dephlegmation in said dephlegmating means.

WILLIS F. SIMS.

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