US1911597A - Assigstob to h - Google Patents

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y 30, 19330 v c. w. ANDREW$ 3,911,597

GAS REFORMING PROCESS Filed Oct. 18; 1928 Patented May '30,- 1933 .UMTED stares ear eras CHARLES W. ANDREWS, OF CHICAGO, ILLINOIS, ASSIGNOR T H. A. BRASSERT & COM- raw, or omcaco, rnmnors,

A CORPORATION OF ILLINOIS GAS REFORMING PROCESS 'This invention relates to a new and improved method for the treatment of gases and more particularly to a method of treatment of oil gas or similar ases of high B. t. u. cona tent and high speci c gravity.

Large quantities of gases of this character are produced in plants for the distillation and cracking of heavy hydrocarbons and oils. These gases result from the processes in which certain of the lighter fractions are driven ofi as fixed gases which cannot be recovered as light oils by condensation. Much of this gas is used for various heating purposes in the oil plant, but large surpluses are created in many cases for which there is no ready commercial sale.

The as is a valuable source of heat and power, but is not adapted for ordinary commercial distribution since it diifers so materially in its characteristics from ordinary city gas specifications. It will be understood that city gas must be maintained within comparatively narrow limits as to B. t. u. value and specific gravity in order that the various types of apparatus used with the gas may be maintained in adjustment and eficiently operated.

In order therefore that this oil gas may be used as a source of supply for city distribution, means must be provided whereby it may be reduced in B. t. u. value and in specific gravity to conform to city specifications.

It is an object of the present invention to provide a new and improved method of treating gases whereby the gases may be eficiently reduced in B. t. u. value and specific gravity.

It is a further object to provide a method whereby the gas may be treated by passing it through a bed of fuel such as coke, in which carbon deposited may be eificiently used in the process. 7

It is an additional object to provide a method whereby the heat of the process may be eficiently conserved and used and the temperature of the fuel bed adequately controlled.

Other and further objects will appear as the discription proceeds.

I have shown somewhat diagrammatically in the single figure of the accompanying drawing, a vertical elevation with parts in vertical section of one form of apparatus adapted for carrying out my improved method.

In the drawing, the gas generator 11 is shown as a water gas generator having a grate 12 and rotating beam 13 for agitating the fuel mass and rendering it of substantially uniform permeability. The chamber is shown filled with a mass of coke 14. The beam 13 is connected at its ends with the ring 15 having the circular ash receiving trough 16. The adjustable scoop 17 is provided to selectively remove ash from the trough 16 as the ring is rotated. The ring rests on roller bearings 18 and is driven by the gear 19, which may be driven by any suitable source of power.

The bottom of the generator unit 12 is completely closed by thehousing 20. Thepipe 21, controlled by valve 22, leads into the housing 20 and may be used for the introduction of steam. The passage 23 leads from the blower 24 into the housing 20, the passage being controlled by valve 25. The passage 26 serves as an air intake for the blower 24:.

The passage 27 enters this passage 23, this and the three-way valve 31; The three-way valve 31 is connected by passage 32 to the wash box 33 and by passage 34 to the regenerator 35. The passage 36 connects the bottom of the regenerator 35 and the upper portion of the generator unit 11. The oil gas passage 37, controlled by valve 38, leads to the top of the regenerato'r 35. \The. city gas oiitake passage 39 leads from the wash box 33 to any suitable gas .using or holding apparatus. The stack 40, controlled by valve 41, leads from the regenerator 35 for the discharge of waste gases.

The pipe 42, controlled by valve 43, leads into the top of the regenerator 35, for theintroduction of steam, if desired. The passage 4A, controlled by valve 45, leads into the bottom of the regenerator for the intro duction of secondary air.

In the operation of the apparatus shown,

in carrying out my improved method the coke 14 in the generator unit 11 is first raised to the desired temperature by air blasting. The blast air is drawn in through passage 26 by the fan 24 and is forced through passage 23 into the bottom chamber 20. Air blasting is carried on in the generator unit 11 and the blast gases pass through passage 36 to regenerator 35 where they are burned by secondary air introduced through passage 44, valve 45 being opened. The valves 31 and 38 may be closed and stack valve 41 opened to permit the discharge of the products of combustion.

In blasting in this manner, the coke 14 in the unit 11 becomes much hotter in a lower combustion zone than it does in the upper part of the unit. This great variation in heat in the unit is undesirable when it is used in the treatment of oil gas by my method, as the gas may be overcracked and excessive carbon deposited in the hottest zone. In order 'to render the heat more uniform throughout the mass of fuel, some of the hot products of combustion may be recirculated with the blast air through the unit. This may be accomplished by opening valve 31 to connect passages 34 and 30, so that some of the burned blast gases may pass down passage 30 to the three-Way valve 28. This may be opened to connect passages 30 and 27 so that the blast gases may be drawn into passage 23 by the flow of air therethrough. If desired, the valve 28 may be turned to lead the products of combustion to passage 29 from which they will be drawn through passage 26 with the air by fan 24-. The quantity of recirculated burned blast gases may be controlled to control the temperature in the unit 11.

After the mass of fuel has been raised to the desired temperature, the flow of air is stopped, valve 25 being closed. The stack valve 41 is closed and three-way valve 31 turned to close off passage 34 and connect passages 30 and 32. Three-way valve 28 is turned to connect passages 27 and 30 and close off passages 29. The secondary air valve 45 is closed and the oil gas inlet valve 38 is opened.

The oil gas is then introduced through passage 37 into the regenerator 35. Here the oil gas receives a preliminary heating and then passes down through passage 36 into the top of the unit 11 and down through the mass of fuel therein. This mass of fuel is kept loose and permeable throughout its area by the rotation of the ash removing ring 15 and the agitating bar 13. From the unit 11 the gas passes through housing 20 and passages 23, 27, 30 and 32 to the wash box 33, from which it passes through passage 39.

The temperature in the regenerator 35 may be such as to cause a deposit of carbon in the regenerator, particularly during the earlier part of the gas run. Steam may be introduced into the regenerator 35 through pipe 42, valve 43 being opened to make water gas with the deposited carbon. Any carbon carried into, or deposited in, the gas unit will eventually be consumed with the coke in the unit.

While I have shown one preferred form of apparatus for carrying out my improved method, and have described certain manners of carrying out my invention, it is to be unders'tood that the method may be carried out in other ways and with other forms of apparatus, and I contemplate such changes and modifications as come within the spirit and scope of the appended claims. Y

I claim:

1. The method of reforming oil gas, which comprises heating a mass of solid carbonaceous fuel by air blasting and controlling the temperature throughout the mass of fuel by selectively recirculating the products of combustion of blast gases during the blasting period, the fuel being heated to a temperature such as to crack heavier constituents of the gas, andpassing the gas through the fuel whereby the heavier constituents of the gas are cracked.

2. The method of reducing the B. t. u. value and specific gravity of oil gas, which comprises alternately air blasting and passing oil gas through a generator containing solid carbonaceous fuel, whereby the heavier constituents of the gas are cracked the gas being preheated by heat derived from the blast gases, and the fuel temperature being controlled and rendered more uniform throughout the mass by recirculating a controlled quantity of the products of combustion of blast gases during the blast period.

Signed at Chicago, Illinois, this 16th day of October, 1928.

CHARLES w. ANDREWS.

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