US1873707A - Catalytic core - Google Patents

Description

Aug 23, 1932- A, E. HARNSBERGER E'r AL 1,873,707

CATALYTIG CORE Filed Aug. 21, 1928 gwuwntoz Patented Aug. a3,l A1932 UNITED STATES PATENT OFFICE AUDLEY E. HARNSBERGEB AND CLYDE I. SMITH, OF CHICAGO, ILLINOIS, ASSIGNOBS TO GYRO PROCESS" COMPANY, OF DETROIT, MICHIGAN, A, CORPORATION OF MICHI- GAN CATALYTIC CORE Application led August 21, 1928. VSerial No. 301,152.

This invention relates to an improved type of catalytic core of the type used in connection with processes and apparatus for cracking petroleumv oils. these processes oil is heated to substantially a state of vapor and is then passed through tubes or pipes for further heat treatment so that the temperature of the oils or vapors willbe raised suiciently to effect molecular decomposition thereof. It has been found in certain systems that by arranging within the tubes or pipes where the oil is heated to cracking temperatures, the conversion reactions are facilitated through bringing such 1l vapors int o contact with reaction promotlng materials, among which may be mentioned ferrous oxide, although other materials are and have been used for this purpose.

l It is desirable in such systems of oil cracking to maintain a uniform iow of oil vapor at constant velocity through the converting elements. For this reason it is undesirable to place the catalytic material in loose or '4 bulk form in the converting elements for the reason that the flow of vapor is rendered ununiform and frequently the tubes or elements are clogged or blocked so that overheating is produced. In the cracking ofpetroleum oils time and temperature are the important factors, and the time factor must be as carefully controlled as the temperature factor. Fpr this reason it has been proposed that cores composed of catalytic substances be provided, wherein the cores are composed of, for example, ferrous oxide mixed with a binder such as cement for the purpose of producing an elongated core possessing uniform diameter and of substantial- 1y solid formation. Such a core, 1n operation, possesses a considerably smaller d1ameter than the inside diameter of the tube or ,l

pipe, or other converting element, in which it is situated, with the result that there remains an annular space in the converting element through which the vapors under heat treatment pass usually at high velocity.

The use of such cores, however, has demonstrated that under practical operating conditions they are very apt to burst, with 5 the result that the tube or converting ele- In certain ofV ment is obstructedand it is necessary to shut down temporarily the operation of the converter until the burst core or filler has been removed and a new one substituted. This is due to the fact that internal pressureis built up therein either by reason of high co-efiicient of expansion, the growth' of the core or liller under high temperatures, or the building up of high gas pressure inside of the core.

We have found that by making the cores more porous and not a solid mass that the conditions mentioned above are largelv overcome. One method of accomplishing this is to produce a mixture consisting of substantially ninety parts of iron oxide and cement and ten parts of sawdust, placing this mixture in a perforated pipe in a packed state and then subjecting the perforated pipe and4 its internal Eller to a high temperature so as to drive ofi' the moist-ure and to carbonize the sawdust. This results in a porous core which permits internal pressure to be readily removed or prevented with the result that the core is less apt to break or burst when subjected to the high temperatures found in the operation of oil conversion systems.

For a further understanding of the invention reference is to be had to the following description and the accompanying drawing wherein:

Figure 1 is a view in side elevation of a catalytic core formed in accordance with the present invention,

y Figure 2 is a vertical sectional view taken through the core showing the latter positioned within the tube of an oil converter,

Figure 3 is a view in side elevation and partly in vertical section of a slightly modified form of core,

Figure 4 is a similar view of a further modified type of core,

Figure 5 is a view in side elevation of the perforated container in which the core is/ formed.

In accordance with the present invention, there is provided a core 1 consisting of an elongated body which is substantially round in a cross section and made of any suitable weight, this being a factor which is regulated by the length of the converter element or pipe 2 in which the core is situated when 1n operation in an oil conversion system. It will be observed that the core possesses an outside diameterwhich is substantially less than the inside diameter of the pipe 2, in order that theremay be provided an annular space 3 between the complemental walls of the core and pipe through which the oil vapors under treatment are passed. The cores may be supported in la central position co-extensive with the axis of the pipe 2 by means of wire legs 4. The latter rest upon the bottom of the pipe 2, and serve to centralize and support the core axially within said pipe and at the same time oil'er the least resistance to the passage ofthe oil vapors through the space 3.

The core is composed preferably of iron oxide, concrete or other cementatious materials which are mixed with sawdust or the like, that is to say, there is employed roughly 10 per cent of sawdust to 90 per cent of iron oxide and cement. These -materials are placed while wet or moist in container 5 which consists preferably of a tubular or cylindrical met-allie body suitably perforated as at 6. The core materials are suitably packed in the container and then the latter is placed in a furnace and subjected to sufficiently high temperatures to drive off the moisture and to carbonize the sawdust content thereof. This results in the production of an extremely porous core in which it will be practically impossible for gas to pocket or accumulate and which will therefore prevent the bursting of the cores and the premature destruction thereof when subjected to the operating tem peratures and conditions which prevail in the converting element or pipe 2 of the oil conversion system.

, The second method for accomplishing similar results is to make the center of the core hollow, as shown in Figure 3. This can be accomplished by placing in the center of the container 5 a wooden rod or staff indicated at 7, around which is packed the concrete and ferrous oxide. This core is then subjected to heat for the purpose of carbonizing the rod 7 to produce an axial passage within the core so that any internal pressure can be relieved through the center section or passage. The core shown in Figure 3 may also include in the body thereof a certain per cent of sawdust so that the walls of the core will be rendered porous.

This form of the invention is also exemplified in the construction disclosed in Figure 4 wherein during the manufacture of the core a small tube 8 of thin metal is inserted in the container and which in the operation of the core could easily collapse under abnormal pressures or strains.

Through the provision of the above construction it will be seen that by rendering the material porous as disclosed provision is made to compensate for high internal pressures to prevent the fracture of such materials and the perforate steel casing surrounding the same. As previously explained, these perforate steel casings were formerly filled solidly with the concrete and ferrous oxide with the result that when the cores or fillers were placed in aconverter tube and subjected to the high temperatures there prevailing, usually 1100 F., the tremendous stresses set up inside of these perforate pipes or cases would result frequently in the bursting of the same. This diiiiculty is believed to be due principally to the growth of the material under the temperature causing high internal pressure. However, in accordance with the present invention the filler or core is rendered porous by the use of the sawdust in the composition thereof, and the resulting porosity.. -produced by the construction results in relieving the strain since it gives room for expansion vdue to the growth of the material under the inuence of heat.

What is claimed is:

1. A catalytic core for oil conversion systems comprising a body of ferrous oxide and a cementitious binder and a wooden rod arranged axially within said body and adapted to carbonize to produce an axial lpassageway through said body when the latter is subjected to high temperatures.

2. A catalytic core comprising a body of ferrous oxide and concrete, there being a longitudinally extending passageway formed axially in said core.

3. A catalytic core prising an elongated substantially cylindrical body of rod-like permanent form positioned axially within an oil conveyin tube of the converter and producingmgsu stantially annular vapor oil passageway between the outer walls of said bod and the inner walls of said tube, and said ody being composed of a porous mixture of ferrous oxide and concrete. .f

4. A catalytic core for tubular oil converters, comprising an elongated substantially cylindrical body of rod-like permanent form, positioned axially within an oil conversion tube, said core producing a substantially annular passageway for oil travel between the outer walls of its body and the inner walls of the tube in which it is situated, said body being composed of a porous mixture of ferrous oxide and a plastic binder, and supporting legs projecting from said core for maintaining the same in an axial position within the tube.

5. A catalytic core comprising a body of rod-like form and produced from a heat treated mixture consisting of ferrous oxide, a carbonizable material and a plastic binder, and a shell surrounding said core and profor oil converters com- Y imago? vided s' m ti licit 'of rfontions p '11p y 'A P0 6. A catalytic core oom'rnnng' a. rod-like form and produled from a mxxtureoonslst' bod f init of ferrous oxide,

s carbonizable mgteriallzgd a. plastic bindgl,

o shell surroun with amultiplioity said core and provid of perforations therein, rojeeting from said body. ereof we ax our signaand leg supports In testimony w tures.

AUDLEY E. HARNSBERGER. CLYDE L. SMITH.

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