US1252401A - Art of distilling hydrocarbons. - Google Patents

Description

J. W. COAST, JR.

ART OF DISTILLING HYDROCARBONS.

APPLICATION FILED NOV. II. 1916.

1,25,4Q1, Patented Jan. 8, 1918 I Q rP/ FQE.

JOHN W. COAST, JR., OF TULSA, OKLAHOMA, ASSIGNOR, BY MESNE ASSIGNMENTS, TO THE PROCESS COMPANY, A CORPORATION OF MARYLAND.

ART OF DISTILLIN G HYDROCABBONS.

Specification of Letters Patent.

Patented Jan. 8, 1918.

Application filed November 11, 1916. Serial No. 130,740.

- lowing is a full, clear, and exact description,

reference being had to the accompanying drawing, forming a part of this specification.

My invention relates to the treatment of hydrocarbons, such for example as the distillates of crude petroleum, the object being to obtain a product of relatively low boiling point from such hydrocarbons, and to otherwise beneficially alter their properties. More specifically stated, .one of the objects of the invention is to improve the known methods of obtaining gasolene from the products which result from the distillation of crude petroleum, and with this object in view the new method preferably includes certain combinations of steps whereby a body of hydrocarbon liquid, moving at a high velocity, is subjected to a very high degree of heat, the resultant vapors being forced into a supplemental cracking chamber. In the preferred form of the invention, the temperature of the vapors in the supplemental cracking chamber is sufliciently high to crack a liquid hydrocarbon, and such liquid in a relatively cool state is introduced into these hot vapors. The result produced is substantially as follows:

The relatively cool liquid, mixing with the hot vapors, causes the vaporized fractions of relatively -high boiling point to condense in the supplemental crack-ing chamber, thereby insuring a product of relatively low boiling point. The intense heat of the vapors is utilized to crack the hydrocarbon liquid separately introduced into the supplemental cracking chamber. Another important point is the elimination of coke or carbon from the retort or primary cracking apparatus. Owing to the velocity of the vapors, all or almost all of the coke or carbon is forced into the supplemental cracking chamber, and it is there acted upon by the comparatively cool liquid which condenses the heavier hydrocarbons in the vapors. The coke or carbon is removed from the vapors in the supplemental cracking chamher, and it maybe readily removed from the bottom of said chamber.

Other important advantages may be obtained by mixing gas or steam and gas with the hydrocarbon liquid before subjecting the latter to the cracking operation.

The drawing is a diagrammatical view of an apparatus adapted for use-in carrying out my method.

To illustrate a preferred method of carrying out the invention, I have shown a retort or primary cracking apparatus comprising a coil of pipe A arranged in a heating chamber B. The coil may consist of 400 feet of two inch pipe. A vapor pipe 1 leads from the coil A to the side of a supplemental cracking chamber C. 2 designates a vapor pipe leading from the top of the supplemental cracking chamber to a condenser 3. A valve 4:, in the vapor pipe 2, may be regu: lated to maintain a predetermined pressure in the supplemental cracking chamber C and coil A. An outlet device attached to the lower end of the supplemental cracking chamber C includes a receptacle 5 interposed between valves 6 and 7. These valves may be manipulated independently of each other to discharge substances from the bottom of the chamber C without materially reducing the pressure in said chamber.

A discharge member 8, arranged within the supplemental cracking chamber, is provided with a multitude of small discharge ports in its bottom face. This discharge member lies above the plane of the vapor inlet and it is connected to a supply pipe 9 provided with a regulating valve 10. A relatively cool fluid, preferably a liquid hydrocarbon, is conducted through the pipe 10 and forced through the discharge memher 8 for a purpose which will be hereinafter explained.

12, 13 and 14 respectively designate pipes for Xonducting oil, steam and gas to the coil Although I have shown and described a] specific structure adapted for use in carrying out my method, it is to be understood that the illustration is merely diagrammatical and that any suitable apparatus may be used in connection with the method herein claimed.

The new method may be followed in cracking various heavy hydrocarbon products resulting from the treatment of crude petroleum, but is more particularly adapted to crack such inexpensive heavy hydrocarbons having a boiling point of about 350 F. to 800 F., the most beneficial results being obtained from hydrocarbons having a boiling point rangin from about 450 F. to about 700 F. T e substance to be treated in the crackin coil A is preferably mixed with steam an natural gas, the mixture being pumped into the lower end ofsaid coil. The crackingcoil A is subjected to a very high degree of heat, preferably from 800 F. to 1500 F. The velocity of the fluid moving through the cracking coil will range from 2600 to 6000 feet per minute.

The valve 4 in the vapor pipe 2 may be regulated to maintain a predetermined pressure in the cracking coil A and supplemental cracking chamber C. This pressure is preferallily between 50 and 150 pounds per square inc A hydrocarbon liquid having a relatively high boiling point is forced through the pipe 9 anddischarge member 8. This comparatively cool liquid, in a finely divided condition, is discharged into the very hot vapors passing from the pipe 1. 'Owing to the intense heat of the vapors, the finely divided liquid is subjected to a cracking operation in the supplemental cracking chamber C. The advantage of utilizing the hot vapors to crack an additional body of hydrocarbons is believed to be apparent. The action in the supplemental cracking chamber will depend primaril upon temperature of the vapors passing rom the cracking coil, the degree of pressure in said supplemental chamber, the boiling points of the finely divided liquid discharged. therein, and the volume of liquid discharged into said cham ber. Only a relatively small volume of liquid can be successfully cracked in the supplemental cracking chamber. For example, the quantity of liquid forced into the'cracking coil may be about five times the quantity forced into the supplemental chamber. The necessary high temperature can be easily maintained in the supplemental cracking chamber, for as previously indicated, the vapors passing from the cracking coil are very hot, preferably between 800 F. and 1500 F., and these vapors are discharged at a high velocity into the supplemental cracking chamber.

The temperature of the vapors in the supplemental cracking chamber is reduced by cool fluid passing from the discharge memher 8, and as a consequence, the vaporized fractions having relatively high boiling pomts will condense and fall to the bottom of the supplemental cracking chamber, instead of passing to the condenser 3.. It will now be understood that the approximate boiling-point and specific gravity of thev product may be predetermined by regulating the valve 10 to control the flow of the comparatively cool fluid through the discharge member 8, thus regulating the temperature of the contents of the supplemental cracking chamber. A product having a desirable low boiling point will flow constantly from the condenser 3, the high boiling fractions being condensed in the chamber C.

Owing to the high velocity of the fluid passing through the coil A, almost all of the carbon or coke will be carried into the supplemental cracking chamber C, and it will fall to the bottom of said chamber. The valves 6 and 7 may be operated as previously pointed out to remove the carbon and liquid from the chamber 0.

Another important feature of the invention consists in mixingnatural gas, or steam and natural gas, with a hydrocarbon fluid and thereafter subjecting the mixture to a pressure and temperature suficiently high to crack the hydrocarbon in. the presence of the other elements of the mixture. In

'thepreferred form of the invention, the

oil, steam and natural gas are conducted to the cracking coil A by'means of the pipes 12, 13 and 14 respectively. By mixing steam and gas with the oil the yield is greatly increased, and a much sweeter and better product having a more desirable initial boiling point is obtained. This seems to indicate that only a very small percentage of the oil is'converted into a fixed gas, or that the natural gas is absorbed b the oil by the action of steam and ahigb degree of heat.

The apparatus herein shown is claimed in an application for patent filed by me Nov. 22, 1916, Serial Number 132,766.

I claim 1. In the art of cracking petroleum hydrocarbons, the method which comprises cracking such petroleum hydrocarbons under pressure and at. a high temperature, conducting the resultant hot vapors into a supplemental cracking chamber, so as to maintain said supplemental cracking chamber at a cracking temperature, forcin a finely divided and relatively cool by rocarbon liquid into the hot vapors contained in said su plemental cracking chamber, thereby su ecting the finely divided liquid. to a crackin operation and at the same time condensing the previously vaporized fractions having relatively high boiling points, and conducting the remaining vapors from said supplemental cracking chamber to a condenser.

2. In the art of cracking petroleum hydrocarbons, the method which comprises cracking such petroleum hydrocarbons under a pressure greater than 50 pounds per square mob and ate. temperature .hi her than 800 F., conducting the 0t vapors at naeaaoa a high velocity into a supplemental cracking chamber, maintaining the contents of said supplemental cracking chamber under a pressure greater than 50 pounds per square inch, forcing a finely divided mass of relatively cool hydrocarbon liquid into the hot vapors confined by said supplemental cracking chamber, thereby cracking the finely divided liquid and at the same time condensing the previously vaporized fractions having relatively high boiling points, and conducting the remaining vapors from said supplemental cracking chamber to a condenser.

3. In the art of cracking petroleum hydrocarbons, the method which comprises forcing such hydrocarbons at a high velocity through a long restricted cracking retort, and thence into a relatively large supplemental cracking chamber, heating said long restricted cracking retort to crack the rapidly moving hydrocarbons,transmitting heat through the resultant vapors to said supplemental cracking chamber so as to maintain the latter at a cracking temperature, maintaining the contents of said supplemental cracking chamber under pressure, at the same time forcing a finely divided relatively cool hydrocarbon liquid intosaid supplemental crackin chamber, thereby subjecting said finely divided liquid to a cracking operation and condensing the previously vaporized fractions having relatively high boiling points and also releasing carbon or coke 'from said vapors, conducting the remaining vapors from said supplemental cracking chamber to a condenser, and removing the carbon or coke from said supplemental cracking chamber.

4. In the art of distilling petroleum hydrocarbons having a boiling point of over 300 F. to obtain a product of lower boiling point, the method which comprises forcing .such hydrocarbons at a velocity greater than 2600 feet per minute through a long restricted retort and thence to a relatively large supplemental chamber, maintaining a pressure greater than 50 pounds per square inch in said retort and supplemental chamber, heating said retort to a temperature higher then 800 F. so as to crack the rapidly movin hydrocarbons, introducing a finely divide and relatively c001 fluid into the hot vapors in said supplemental chamber, thereby freeing the carbon or coke from said vapors and causing it to drop in said supplemental chamber, conducting the remaining vapors to a condenser, and removing the carbon or coke from said supplemental chamber.

5. In the art of treating petroleum distillates having a boiling point of over 300 F. to obtain a product of lower boiling point, the method which comprises mixing sucl? distillates with steam, forcing the mixture at a velocity greater than 2600 feet per minute through a coil of small pipe and thence to a "supplemental cracking chamber, maintaining a pressure of from 50 to 150 pounds per square inch in said pipe and supplemental cracking chamber, heating. said plpe to a temperature between 850 F. to 1500 F, so as to crack the rapidly moving hydrocarbon fluid, introducing a finely divided and relatively cool petroleum distillate into the hot vapors confined by said supplemental cracking chamber, thereby cracking the last mentioned distillate, at the same time condensing the previously vaporized fractions having relatively high boiling points and also freeing carbon or coke from the vapors conducting the remaining vapors from sai supplemental cracking chamber to a condenser, and removing the carbon or coke from said supplemental cracking chamber.

6. In the art of treating petroleum hydrocarbons having a relatively high boiling point to obtain a product of lower boiling point, the method which comprises mixing steam and natural as with such hydrocarbons, forcing the mixture at a high velocity through a cracking apparatus, subjecting said rapidly moving mixture to a degree of heat higher than 800 F., at the same time maintaining a pressure greater than 50 pounds per square inch in said cracking aparatus, thereby cracking the hydrocarbons 1n the presence of said steam and natural gas, and thereafter condensing the resultant vapors.

JOHN W. COAST, Jr.

Images