US1217367A - Open-hearth furnace. - Google Patents

Description

UNITED-STATES `FArFnrr oFFioF.

NnLsoN THOMAS AND ANsoN W. ALLEN, oF BIRMINGHAM, ALABAMA.

, OPEN-HEARTH FURNACE.

Specification of Letters Patent.

Patented Feb. .27, 1917.

original application filed- '.raiy lo, 1914, serial No. 850,131. 'Diiified and 'this appiication filed necinher 16',

' 1915. serial No. 67,151.

To all whom t may concern Be it known that we, NELsoN ANsoN lV. ALLEN, citizens of the United States, and residing at Birininghain,in the' county of Jefferson, State of Alabama, have invented certain new and useful Improvements in Open-Hearth Furnaces, of-Which a furnace adapted for the burning of byroduct wasl therein.

This application is a division'v of my application, Serial No. 850,131, filed July 10,

1914, and which was patented- Feb. 15, 1916,- Y

It has not heretofore been found possible or practicable to employ by-product gas in open hearth furnaces.A By the term byproduct gas we refer to gas evolved in the making ofv coke `from coal 1n retort ovens. The reasons for the lmpracticabillty of burnin-O' this gas may possibly relate more to the lack of adequate facilities in the construction of the open lieartll furnaces than to the character of the gas itself.. We `have found, however, that such gas may be burned 1nopen hearth furnaces to advantage and Withoutmaterially altering the port construction of the furnaces.

In the utilization of by-product gas it has been found essential to highly heatthe same in order to secure complete and speedy combustion. We accomplish this result in the present instance by constructing the furnace with a main and auxiliary air flue, the gas A being supplied to the auxiliary flue by means of thegas, that is combustion to the extent,

of a gas pipe, short of the mouth of the auxiliary flue, thus leaving a space within which primary com#l bustion may take place. By such mechanism we are enabled to cause partial combustion permitted. by the limited volumeof air in the auxiliary flue, thus highly heating the remainder of the gas, which is ejected into the larger space and mixed with the required volume of air to cause complete and speedy combustion.

It will be noted that the open hearth furi nace is not lgreatly 'changed from the design heretofore commonlyV in use, except by the l. fg 1iti01 1 thereto of the gas burning means ""and the changing of thefunction of one of THOMAS and which gas pipe terminates that'- of supplying gas to that of supplying air.

The invention will be more readily understood by reference to the accompanying drawings, wherein- Figure l is al longitudinal vertical section through an end of a tilting .open hearth lfurnace, to which our invention has been apl plied;

Fig. 2 is a transverse section on the line Elf-2 of Fig. l, andv Fig. 3 is a section' on the line 3 3- of Fig. 1;.'

Referring more particularly to the drawings, it wil be seen that we provide an open hearth furnace 10 which, in the present instance,is ofthe tilting type. 'The end construction consists in an end-wall 11,'a lower wall 1 2 and an upper wall 18, wit-hin whichv walls is provided a main ail-V flue 14 and an auxiliary air flue 15. The main air fiile is divided as shown in Fig.l 2, the two l,portions uniting at apoint abovethe division arch 16, the auxiliary flue extending underneath the arch-16. .In View of the fact-that when the furnace is reversed the heat around the arch 16 is very great, we Vprefer to provide within the arch the longitudinally extending .Water-cooled. boxes!A 17, laid, as shown `in Fig. 2, with their sides in engagement, thus forming a self-supper,ting arch.. 7Water is supplied/tol these 'boxes by -meansl ofthe.-

plpe 18.

Extending intothe ai'ixiliary'iue "15 is a gaspipe' 19, surrounded by 'a further pipe 20, between which pipes water'may be cir# Culated to prevent overheating. Gas is supplied to the pipe l19 by the main 21, having a vvalve 22 therein. 'by means of which -the supply is controlled. Located centrally within the gas pipe- 19 is a high pressure air pipe 23, the end of which is located near the mouth 4of the gas pipe. Ye prefer to maintain the pipe Q3 centrally within the gas pipe` by means ofv abend '2l in the ail-pipe. as shown. l f It will be noted that the gas pipe is termi'- nated short of the nose of the arch 1G, thus leaving a space which acts as a coinbustion chamber (if-limited volume. the walls ofv which chamber are constricted near the mouth of the chamber, as best shown in Flgs.

, 1 and 3. tapering the chamber and inaking the mouth. thereof of reduced cross-sec-v initial combustion takes place, that -is such combustion as is possible. in view of the limited volume of 'oxygen' present. This eolll'ibustion, however, highly heats the .un-

consumed gas and this is delivered into the main combustion space at the conlux of-'the t\1v o ues, where complete combustion takes p ace.k

The direction ofthe flame is controlled to a certain extent by means of the high pressure air pipe 23. rlhis, taken in connection with the tapering of the walls of the chamber 25, enables us to utilize a very high degree of heat Without directing the flame against the roof or side walls of the open hearth furnace.

l lt will be understood, of course, that the air supply through the flues 14, 15 may or may not be regenerated, as desired, preferably, however, it will be highly heated by passing through regenerators, as is customary in the operation' of such furnaces.

i We claim: f

1. Ilnan open hearth furnace, the combination of Walls providing a plurality of vertical Hueswhich are turned at an acute angle in order to extend in a downward direction toward the hearth of the furnace and a pipe projected through the furnace endwall across one of said verticallues and extending in a line substantially parallel to the downwardly extending portion of said flues, said pipe terminating short of the outlet from the flue in which it is mounted, substantially as described.

2. In an open hearth furnace, the combination of furnace walls providing a plurality, of uptake ues, said flues being turned at their upper ends to' projectv downwardly toward the furnace hearth, said lues .having a common inlet port to the furnace, and a pipe projected through the furnace end wall across an intermediate vertical flue and in line with the downwardly extending portion of said flue, said pipe being arranged to deliver fluid in line with the travel of the Huid 1within the -iue and thereby avoid whirls and cross currents, substantially as described.

In witness whereof we have hereunto set our names 1n the presence of two subscrlh-

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