US1715341A - Process for converting hydrocarbon compounds - Google Patents

Description

May 28, 1929. M. W. coLoNY PROCESS FOR CONVERTING HYDROCARBON COMPOUNDS Filed Jan. 3, 1927 bbvDNmhl ?atented May 1929. p

UNIE@ STATES y N antan Parana" charca.

MYRON W. COLONY, TEXAS CITY, TEXAS, ASSIGNOR TO PETROLEUM CONVER- SION CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELW 1' My present invention relates to a process for converting or cracking hydrocarbon compounds into compounds of lower molecular weight and more particularly it seeks to utilize steam in a manner to improve the efficiency of the process and the quality of the product.

In accordance with the process disclosed in the United States Patent to Knox, No. 1,428,- 641, the oil is heated to the cracking temperature by contacting therewith hydrocarbon gases of suiiicient temperature and heat units.

. In a subsequent pending application, Serial No. 587,191, Knox disclosed improved means for heating the gases constituting the heat carrier, such means being of the regenerative type. Experimental work has demonstrated that When'hydrocarbon gases are used there is the tendency to deposit carbon in the checker-work, or other refractory bodies constituting the regenerative heater. This carbon deposit, while it permits the process to be carried on for periods of time, is nevertheless troublesome, since the stove must be periodically disconnected from thek system and cleaned, as a carbon deposit of more than a certain amount cuts down the efficiency of the stove.

rIhe reasons for using a hydrocarbon gas as a heat carrier, are set forth in the patent and application above referred to. Chief among these, is that in any cracking reaction there are produced large quantities of noncondensble gases, which are available for use in this Way. Furthermore, it is considered that these gases of hydrocarbon origin may afford a more favorable atmosphere for the crackin reaction than do ypurely neutral gases w ich, if used, would not deposit carbon on the checker-work.

f I have now discovered that a satisfactory solution of the above mentioned difficulty will be had by the use, along with the hydrocarbon gases, of considerable amounts of steam. In other words, I have found the presence of lthe steam in the blast stoves inhibits the deposition of carbon to' a satisfactory degree without adversely adecting the action of the heated hydrocarbon gases in the conversion chamber. Moreover, when steam-is used, it will be found that after the products of the system have traversed the l condenser, the volume of gases uncondensed will ofcourse be smaller, and this will facilitate the stripping therefrom of the light vapors,the presappiication med January s, 1927. serial no. 158,757.

ence of which is so desirable in motor fuels.

1With respect to the nature of the action of the steam in inhibiting the depostion of the carbon, I attribute same to its property of combining with the carbon at sufficiently elevated temperature to produce carbon oxides and hydrogen.

In case some carbon is formed the amount will be so slight as to permit of its ready combustion during the blasting period.

I have illustrated suitable apparatus for carrying out the invention in the accompanying drawing forming part of this specification. In this drawing the figure shows diagrammatically a layout of a plant in which vmy invention may be practised.

' connected thereto by means of a pipe 17 The u'ids, heated in the stove are led therefrom through the pipe 18 and are admitted to a conversion chamber 20 which may be provided with checker-work 21 for the purpose of insuring mixing of the gas and oil.

Oil is also admitted to the chamber, preferably in vapor form, being generated in the still 23 of known type, and conveyed therefrom` into said chamber through pipe 24. The oil is fed to the system preferably through a preheater 25 and pipe 26, leading therefrom to the still 23. The products of the reaction chamber leave the chamber through pipe 28, thence through preheater 25, Where they give up a part of their heat to the incoming oil, after which they are passed to a condenser 29, it being understood that various intermediate appara-tus may also be ernployed, whereby to fractionally condense the Said stove, as is cus-4 products and also to heat the incoming oil.

As disclosed in the Knox application before mentioned, I tind it desirable to pass a part of the vapors generated from the incoming oil in the preheater 25 back into the reaction chamber 2O employing pipe 25a for this purpose.

The products which pass through the condenser 29 are thus separated into theaconfdensible materials which may comprise water and the lighter liquid hydrocarbons collecting in the receiver l 30, whereas the gases which are uncondensedl pass through pipe 31 into the receiver 32 or are returned to they stoves, as desired. Normally they are conducted through a pipe 33 back into stove 10, being assisted thereto by means of a pump 34. Receiver 32 is cut in and out of the system by using valves 32a, 32'D and 32. Preferably, I interpose a stripper or absorber 31a of known type after the accumulator 30-y pipe 12 and hydrocarbon gas through pipe 33 or other source will be admitted to the stove, and pass therethrough and thence into the conversion chamber 20. 4Simultaneousl with this, oil vapor will be admitted to the chamber from still 23, bymeans of pipe 24. The temperature for cracking may be taken from 700 to 800 F., as a minimum and the temperature prevailing in the blast stove will in general run from 1500o to 1800 F. lt will be understood that the temperature of the gases will be suitably regulated by commingling therewith a portionof the cold gas which is by-passed through pipe 35 into the pipe 18. Ordinarily this will be accomplished automatically by thermostatically controlled means.

After a stove has run until its tempera ture has dropped below the desired minimum, it is cut out of the system and blasted with a suitable fuel. As has been previously mentioned, in case a slight deposit of carbon is left in the stove, a sufficient excess of air isv admitted in the blasting period to consume thls, as well as the fuel added. In this way the stoves are connected and efficiently heated to the desired temperature, after which they are cut into the system in an obvious way.

It will be understood that in view of the intense heat to which the hydrocarbon gases are subjected in the hot blast stoves, vsuch gases will undergo decomposition to a considerable degree, and their composition will approach a mixture of hydrogen and methane almost entirely. Accordingly in theclaims, the expression hydrocarbon gases will be understood to include gases of this general composltlon. v

What I claim is:

1. The process of treating hydrocarbon' compounds to convert the same into others `of ower molecular weight, which consists in sepsuch relative volume as to accomplish sub-l st-antially the entire reaction of conversion and constituting substantially the sole source of heat therefor, controlling `the temperature of the reacting compounds whereby the conversion of said hydrocarbon is brought about under substantially uniform temperature conditions, the'products from said react-ion chamber containing thev vapors of the ldesired compounds of the process in addition to thesteam and hydrocarbon gas, and subjecting the products from said chamber to conditions producing liquefaction of said Y compounds suitable as motor fuels.

2. ln the process of treating petroleum oils to convert them into compounds suitable as motor fuels, the steps which consist in maintaining a quantity of petroleum compounds undergoing ltreatment in a closed reaction chamber, heating up a mass of inert, refractory, heat absorbing material until said ma terial is above the temperature required for the conversion reaction, passing a carrier gas including steam thereover, and thence into said reaction chamber, controlling t-he temperature of the said ,reactingcompounds whereby t-he conversion of saidy petroleum compounds is brought about under substantially uniform temperature conditions, the products from said chamber containing the vapors of the desired compounds of the process in addition to the carrier gas, and subjecting the products from said chamber to conditions producing liquefaction of said compounds suitable as motor fuels.

3. The process of treating hydrocarbon compounds to convertthem into compounds suitable` as motor fuels, the steps which consist in heating up a mass of inert, heat retaining material until said material is above the conversion temperature, passing a mixture of hydrogen containing gas and steam thereover, and thence into a reaction chamber, separately vaporizing thenhydrocarbonY to be converted without substantial cracking thereof, introducingthe vapor produced by the evaporating step mentioned into contact with the thus heated mixture ofhydro en containing gas and steam in said cham er, controlling the temperature of the reacting compounds whereby the conversion of said hydrocarbons islbrought about under subthe products from said chamber containlng 'the vapors of the desired compounds of the process in addition to the carrier gas, and subjecting the products from said chamber to conditions producing liquefaction of said Compounds suitable as motor fuels. v

Ja-In the process of treating hydrocarbon oils to convert them into compounds suitable as motor fuels, the steps which consist in heating` up a mass of inert, refractory, heat absorbing material until said material is above the temperature required for the conversion reaction, passing a heat-carrierv gas including steam thereover, adding a varymg quantity of relatively cold gas to said heated gas as said mass cools down, whereby the produced mixture is maintained at a substantially uniform temperature above the conversion temperature, then introducin said heated mixture into a reaction cham er, separately vaporizing the hydrocarbon to be converted without substantial crackin thereof, introducng the produced v'apor into contact with said heated mixture in said reaction chamber, whereby the conversion of said hydrocarbon is brought about under substantially uniform temperature conditions, the products from said chamber lcontaining the vapors of the desired compounds of the krprocess in addition to the carrier gas, and subjecting the products from said chamber to conditions producing liquefaction of said compounds suitable as motor fuels.

In testimony whereof I have aifi'xed my signature to this specification.

MYRON W. COLONY.

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