US1702540A - Process for refining oil - Google Patents

Description

Filed Ma rh 12. 1926 Jmvgrqtzu Eric 71:. Hess/e Patent ed Feb. 19, 19 29. I

- UNITED STATES 1,702,540 PATENT OFFICE.

mo 0:. nassnn, or 1mm, rumors.

rnooass ron'nsrmme om.

Application med March 12, 1926. Serial No. 94,122.

This invention relates to a continuous process for the conversion of hydrocarbon oils into products having lower boiling. oints and containing unsaturated compoun s. 1 More par-- ticularly it relates to a continuous process for refining oils, such as crude petroleum oil, its

distillates and residues, tar oil, brown coaltar oil, shale oil and similar products.

In my copending application for a ?continuous process for the refining of'oil, Serial No. 67 8,924, filed Dec." 6, 1923, I have described a catalytic process for the conversion 'of hydrocarbon oils into products having lower boiling points. In that process I brin the oil into a suitable state for being. acte upon most efficiently by the catalyst by producing a fog of oil and hydrogen or a gas c'ontaining hydrogen. I now propose to use in place of the hydrogen containing gas, the vaporsof oils or distillates having ower boiling points than the oil to be" treated, such as" paraflin oil, light lubricating. oil, gas oil, kerosene, gasoline, and the like, and thereby to produce lower'boiling conversion products' of unsaturated character. 7

It is generally conceded at the present time, that for motor fuel gasolines containing unsaturated hydrocar ons possess desirable advantages over saturated hydrocarbons belonging to the C H series. Among these advantages is the anti-knock is characteristic of unsaturated asohnes and benzenes. Therefore, the addition of hydrogen during the conversion of the higher boil ing hydrocarbon oils is no longer a desirable I step.

' in statunascendi' during the crackinfg a cer-" .present natu ally during the'crac 11 Furthermore, it is unnecessary to add hydrogen for the reason that in the ordinary processes the tail gases usuallycontain approximately 6% to 10% ofhydrogen. Much.

more than'6 to 10% of hydrogen ispresent reaction, and this hydrogen takes care 0 tain amount of hydrogenation. If fuel" or gas oil is to be cracke enough hitilrogen is process tootake care of a certain amount of ydrogenation. About one-quarter of the cracked gasolines are olefines, but an even larger ercentagewould be desirable in view of t eir anti-knock properties. 7 1

For crac very heavy hydrocarbons, or hea or hal solid, residues and asphalts, whi ch do not contain enough hydrogen in the molecules to form lighter hydrocarbons, it

would .ordinarily be advisable to add hydroproperty, which gen in order to prevent'carbon deposits, but

by using the vapors of lighter distillates as a medium for the production of a fog, as in my present process, some hydrogen is formed by the breaking down of these vapors. This hydrogen, whlch is in statu nascendi and therefore more active, is sufiicient, although present in only limited quantities, to serve larger quantities of the same purpose as added hydrogen.

It is therefore an object of this invention to provide a process for the conversion of hydrocarbons into products of lower boiling point in which kerosene or other light distils late vapors are employed to assist in the process.

It is a further objectof this invention to employ an oil fog producing device using .the vapors of li hter distillates as the carriermedium for t e fog.

, It is a further object of this invention to apparatus, with parts in section.

Figure 2 is an enlarged sectional detail view of my oil fog producing device.

The oil to be converted is pumped of a pump 1 through a preheating coil 2,

mounted in a channber 3 above the firebox 4 of a furnace 5. Said furnace. 5 may suitably by means.

be provided with a gas or oil type burner 6 adapted to be easily controlled. A damper or gate 7 between-the fire-box 4 and the heating coil chamber 3 serves to rfgulate the temperature in said chamber. ispreheated to a temperature of 200 to 350 C. under a pressure. of3. to 8 atmospheres depending u on the characteristics ofthe oil to be treate from the The oil then preheater coil 2 through an i fi ted-pipe 8 coil in the coil 2* into an oil fog producin device 9 of my" special 00 truction. Saicf oil fog producing device 9 extends through a side wall-of a reaction kettle 10 which issupported in the brick work of the furnace 5 and is suspended,

as shown, in a compartment 11 thereof. A

control damper 12 is located between the'fireand is bolted thereto through an integral flange portion 14. A Y-fitting 15, threaded into said body portion, provides an oil passage 16, adapted to be connected to the pipe 8 and a communicating passage 17 having a needle valve 18 for controlling the flow of oil through a nozzle 19 on the inner end of said passage 17. Said nozzle 19 together with an opposing nozzle 20 are positioned in a recess 21 provided for the purpose in the lower side of said body portion 13. a The nozzle 20 is connected by means of a passage 22 to a pipe 23, which serves to introduce some suitable gas or vaporinto the fog producing device, as will later be explained.

Said pipe 23 leads back to a preheating coil 24, positioned in the compartment 11 and serving, first, to vaporize'the oils or distillates having lower'boiling p'oints than the hydrocarbons'to be treated, and secondly, to preheat these vapors as well as the tail gases. Said kettle 10 is preferably a relatively deep round bottomed kettle having a vertical partition 25 therein which extends from the v top of the kettle to a point near the bottom thereof, as shown, and divides the kettle into two compartments 26 and 27 commu nicating with each other at the bottom of the kettle. Compartment 26, which includes" the fog producing device 9 is preferably smaller han compartment 27..v The top of the kettle 0 has a flanged cover 28 in which are mounted a pressure gauge 29 and a ther-- mometer well 30.- The temperature within the reaction vessel is in general maintained between 250 and 400 0., depending upon the nature of the oil which is being treated.

' If. workingon gas oil the temperature employed is usually-280 to 350 C., but if work ing on lower boiling hydrocarbons the temperature may vary. gOn the other hand if,

operating onhigh boiling residues and asphalts the temperature rises to between 350 fandAOO? C.

Within the kettle 10 is placed a decomposition catalyst of my invention, composed 0 tin containing a small percentage of=anti mony. Such a catalyst gives very satisf tory results in effecting the-decomposition of the h drocarbon oils. Specifically, I have found om experiment that if only 1% of antimon is'jis ed, the highest decomposition factor is obtained.

The catalyst within the kettle 10 is maintained'in a molten state at the temperature above mentioned of between 250 and 400 C."

The oil-running from the preheater', 2 through pipe 8 is discharged through the'-'valve ated nozzle 19 against the vapor issuing arouse from the opposing nozzle 20. This vapor may be any vaporized lighter distillate than the oil to be treated. This vapor used is first preheated in the coil 24, having radiant disks for the better distribution of the applied heat and located in the chamber 11, up to the temperature of the oil delivered from the preheating coil 2. The lighter oil or distillv ate vapor is introduced in the heating coil 24 through an intake pipe 65, under a pressure greater than thepressur'e of the oil de-.

liver-ed from the preheater 2. This tends.

toward a more balanced delivery of the gas in the fog producer 9, and produces a real fog intermediate the opposing nozzles.

The concussion of the oil from the nozzle 19 and of the vapor from the nozzle 20 results in the formation ofa grayish yellow fog. It

is important for the formation and maintenance of this fog that the temperatures of the oil and vapor be the same and that the fog be produced at the temperature of the reaction kettle. Accordingly I have found.

that the production of the fog'is most satisfactory if brought about within the reaction kettle itself.

The pressure of the fog formed in the smaller compartment 26' of the reaction kettle depresses the molten catalyst, which rise by a corresponding amount in the other compartment 27. Since no pressure of gas is mainvtained above the molten metal in compartment 27, the fog in compartment 26 is forced 'by its own pressure down through the body' of the metal in compartment 26 and up into compartment 27 The oil in passing through the catalyst remains in its condition as a fog until by virture of the decomposing action of the catalyst it is converted into oils of such lower boiling points that under the conditions and pressures obtainingsaid oils are vaporized. It is evident, therefore, that the conversion into hydrocarbon, oils of lower boiling point take place strictly in a liquid phase. This is an enormous advantage since the volume of' cataylst and reaction vessel 4 need not be nearly so great as if the decomposition occurred in a gaseous state.- f

' The vapor used as a carrier medium for the fog will also be subject to the decomposition action-of the molten catalyst, this vapor eing largely broken down into lower boiling OdllCtS;

I suflicient quantity. to hydrogenate' to any substantial degree the con-.

ertain amount of hydrogen from the decomposition of version products of the -oil. These conver-' I sion products will therefore contain a considerable quantity of unsaturated hydrocarbons,

which are now deemed desirablein the motor fuels. Furthermore the small amount of hydrogen formed is sufficient revent the molten catalyst. from being 1) ned.

I The vapors of the converted hydrocarbon oils accumulating above the molten metal in compartment 27 are led off through a conduit 31 into the base 32 of a fractionating column 33. The base 32 is filled with an absorbing medium 34, such as iron and manganese oxides, or other suitable desulphurizer, for the-purpose of removing any sulphurous compounds that may be present. The fractionating column 33 may be provided with a condensate trap 36,,above which the tower 33 may be filled with suitable packing rings, or it may be arranged in any of well known manner for effecting fractionation of the oil vapors. At the top of the tower 33 is provided a straight tubeoondenser 37, from which the condensates formed therein'trickle down onto the trap 36. From there the condensates are discharged through a pipe 38 into run-down tanks 39. From the top of the tower 33, the vapors and gases are led through a pipe40 into the base of a second fractionating column 41 which may be similar in its design to the fractionator 33. From the column 41 the condensates pass by way of pipes 46 into run-down tanks 47. The vapors and gases from said fractionator 41 pass out at the top of the column through a pipe 48 into a final condenser 49. From said condenser 49 the condensates pass through a pipe 50 into run-down tanks 51. The uncondensed gases from the final condenser 49 are conducted by the pipe 52 to the compressor 53 which delivers said gases at the pres sure of approximately 15 atmospheres through the pipe 54 into a pressure tank 55,

cooled within by means of straight water tubes 60. On the top of this tank there is a pressure relief valve 59, which is so regulated that it. blows off to maintain the gas in the return pipe 58 at a certain pressure depending upon the gravity and viscosity of the oil. Another relief valve 61 is provided for relieving the amount of gas not needed for recirculation to gas burners under the still. The cooling of the compressed vapors in the pressure tank 55 results in the condensation of a portion of the gas. The condensates so formed are led through the pipe 56'into pressure run-down tanks 57 and the uncondensed tail gases are led off, as explained, at

a certain pressure from the tank 55, through the return pipe 58 back to the preheater 24 and thence to the fog producing device 9. In this way the tail gases supplement the lighter oils or distillates-introduced into the system under pressure through the pipe 65. I When treating heavy hydrocarbons, asphalts and the like, a lower boiling oil may be I mixed with these heavy hydrocarbons to I make them more fluid and this mixture then hydrocarbons having motor fuel value, and,

(5) that olefines, and aromatic compounds are formed that have desirable anti-knock properties.

I am aware that numerous changes may be 'madewithout departing from the principles of this invention, and I therefore do not purpose limiting the patent granted otherwise than necessitated by the prior art.

I-claim as my invention:

1. A process ofconverting hydrocarbon oils into lower boiling products, which includes directing the oil against a counter current stream of a hydrocarbon vapor under sufiic-ient pressure to form a true fog of highly dispersed liquid oil suspended in said vapor, and passing saidfog througha decomposition catalyst whereby decomposition of the oil and vapor take place to form lower boiling products. 2. A process of oils into lower boiling products, which includes directing the oil against a counter current stream of a hydrocarbon vapor under suflicient pressure to form a true fog of highly dispersed liquid oil suspended in said vapor, and passing said fog through a molten decomposition catalyst, said catalyst being :maintained at a temperature of between 250 and 400 Cywhereb decomposition of the oil and vapor take p ace to form lower boil- 7 ing products.

3. A process of converting hydrocarbon oils into lower boiling products, which comprises directing the oil against a countercurrent stream containing a hydrocarbon vapor under sufficient pressure to form a true fog of highly dispersed liquid oil suspended in said vapor, and bringing said fog into contact with a decomposition catalyst comprising a mixture of tin containing a small quan- -tity of antimony to effect decomposition of the oil and vapor into lower boiling products.

In testimony whereof I have hereunto subscribed my name.

ERIC TH. HESSLE, PH. 1).

converting hydrocarbon

Images