US1068424A - Method of operating hot-blast stoves. - Google Patents

Description

J. 0. GORMAN, JR. METHOD OF OPERATING HOT BLAST STOVES. APPLICATION FILED PEB.2 5, 1911.

1,068,424, Patented July 29, 1913.

(5%) of air.

C. GOZEMAN, JR.,

is 4 t GF CHICAGQ, ILLINTEIS.

METHOD OF OPERATING HGT-BLAST SIGVES.

essee Specification of Letters Patent,

To aZZ whom it may concern:

Be it known thatl, Jlmzns C. GOR AN, Jr" a citizen of the United, States residing at (lhicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Methods of Operating Hot-Blast Stoves, of which the following is a specification.

My invention relates to a. method and appcratus for obtaining an intimate and proper mixture of gas and air, and is especially although not exclusively) adopted for use in connection with hot-blast stoves 1 blast furnaces for smelting iron.

' As is Well known, in the operation of the ordinary type of blast furnace a large amount of combustible gas-is-formed, this gas being conducted from the top of the furnace through suitable fines. After proper cleaning the gas is used for obtaining host under'boilers, for operating gas engines and for heating hot-blast stoves. In connection with the last-mentioned use of blast-furnace gas, it has been customary to introduce the gas into a combustion chamber Within the stove and to simultaneously introduce air into the some chamber through separate ports or fines, these ports being placed at various horizontal angles from each other, and not necessarily in the same horizontal plane Tie mixture of gas and 311' takes 'place within the combustion chamber. A

very serious disadvantage of this method of operation consists in the fact that there not a perfect mixture of air and gas, and either excess of air or an excess of gas, or even e inixture of unburned gas and air escape through the stack of the stove. This condition is shown by the following actual analyses of the chimney gas:

September 6th 1910. 14.0 9.2 0

trogen, Will he apparent that for every one per cent. (1%) of oxygen contained in the chimney This excess of air materially lowers-the combustion temperature Within the stove, and, in turn, affects the quantity of heat which is absorbed by the checlier gas there. will be five per cent.

t attente d July 2th. 3,

Work through which the products ofcombustion pass after leaving the combustion. chamber during; the heatingup period of the stove. Any unburned carbon monoxid in the chimney gases has the some efi'ect as the presence of excess air. In both cases the heat absorbed by the hot blast during the blast period is largely decreescch re.- sulting in either increased fuel consumption 6 for a given tonnage of iron or less iron for a given amount of fuel.

In my improved method of operation the gas-and air are intimately and perfectly mixed before theilgentrunce to the con1bus- 7O .tlon chamber of the stove, thus ZillOWlTlg practically perfect. combustion, as shown from the following analyses of the chimney gas which were obtained after the instullutlon ,off my improvement:

i col. o 00. i I o i"""""i November 9th,1il0 ..I 26.4% .4 u i'flth lillfl 210 .8} 0 12th,l9l0... H: 25.4 .s; u go it result of thegreetly improved coin- DUSUOH demonstrated by the above analyses t Wlll apparent that a given amount of iuel will create iv much highertemperature within the combustion chamber which, in turn, sinuses the checker work to be heated to a higher temperature, and during the blast period causes the hot blast to absorb more heat. By actual experiment it has o been demonstrated that from ltlto 2511 2 of gas is saved by the use of my imp-moments. so ikstill further advantage of my invention consists in the fact that combustion takes place as soon as the mixture of gas and air 9 reaches the combustion chuzuber and the flame is confined to the lower portion of said chamber, whereby the life of considerably lengthened. By the old method of mixing the air and within the combustion chamber. itself combustion takes place throughout the length of the chambenund very. frequently in portions 1? the checker work, thereby greatly shortening the life of the stove. 1

A still further advantage resides in the production of more intense heat within the combustion chamber whereby more of the is sintered and tells to the bottom of the combustion chamber This results in much less dust being; carried over into the checker work than by the bid process, and

m'onoxid passing through the stove with -a consequent loss of heat.

The various advantages of my improve= ments will be more readily understood by, nreference to the accompanyin drawings,- gb' hich show a preferred embodiment of my;

invention, and in which Figure 1 is a diagrammatic vertical section through a hot-blast stove, showing my: improved burner applied thereto; Fig. 2 is? a sideel'evation of the gas flue and the burner connected therewith, and Fig. 3 is a transverse section on the line 3-3 of Fig. 1. The hot-blast stove 10 has a combustion chamber 11, connected with the upper end of which is the chamber 12 containing the checkers 13, the combustion chamber 11 being separated from the chamber 12, containing the checkers, by means of the vertical wall 14:, according to the well-known construction. Toward the bottom of the combustion chamber 11 is the gas inlet port 15,

' connected with which is my improved gas burner 15. This burner is also connected with the flue 17, which, in turn, is indirect communication with the gas main 18, the slide valve 19 being provided between the gas main 18 and the flue 17.

The gas burner 16 consists of a cylindrical pipe 20 having in its sides one or more openin s 21. This pipe 20 projects within the in ct port 15, and a tight connection is formed by means of the ring 22 inclosing the pipe 20 and abutting against the outwardly projecting fire brick flange 23, which is preferabl'y strengthened and supported by the frame 24 bolted to the maincasing 25 of the stove. The pipe 20 at its exterior end is provided with'the flange 26. Inclosing the pipe 20 is the sleeve 27 having therein the opening's 28 which may be brought in register with the openings 21 of the pipe 20. It will .be apparent that the size of the openings from theexterior tothe inside of the pipe 20 may be regulated-as desired by proper rotation of the sleeve 27. -Mounted within the pipe 20 is the reducer 29, of a general cone shape, and having in its end the opening 30 of considerably sniallerdiameter than the inside diameter of the pipe 20. The reducer 29 has the flange 31, which is riveted between 1-,oes,4.24

the flange 26 of the pipe 20 and the flange 32 of the gas flue 17. The gas fine 17 is preferably bent in the shape of a rightangle, and has passing therethrough the air inlet pipe 33, which passes through the opening 30 of the reducer 29, and is preferably provided with the damper 33 to regulate the supply of air.

The method of operation of my improvements may now be readily understood. The gas passes from the gas main 18 past the slide valve 19 into the flue 17, and from said flue through the openingv 30 of the reducer 29, intothe pipe 20. As the body of gas of reduced cross-sectional area passes through the opening 30 of the reducer 29. it draws air through the openings 28 and 21 of the sleeve 27 and pipe 20, this air then becoming intimately mlxed with the gas and being of an amount proportional to the adjusted position of the sleeve 27. When the gas reaches the end of the pipe 33 an additional amount of air is drawn from the exterior through this pipe and also intimately mixes with the gas. The mixture of gas and air which has been thus formed then passes into the inlet port 15, and thence intfi'the combustion chamber 11'. As is well understood, the temperature within the combustion chamber is high, thereby causing the mixture of gas and. air to be ignited, and a practically complete oxidation of the carbon monoxid to carbon dioxid is effected in the lower portion of the combustion chamber. The further course of the products of combustion is the same' as takes place in the usual practice, the gases passing upwardly through the combustion chamber- 11 into the chamber 12, containing the checkers 13, then downwardly through said checker work, and finally into the flue 34 which is connected with the stack of the stove. During the blast period the blast is first introduced through the flue 34 by the regulation of suitable valves, then passes upwardly through the checker work chamber 12, from which it passes to the blast furnace, in the well-known manner, through a port, which, for thesake of simplicity, is not-shown in the diagrammatic representation' of. Fig. 1.

It will be apparent to those skilled in the art that the details of the method of opera.- tion and also of the apparatus which I have described may be varied within wide limits without departing from the spirit or scope of my invention.

I claim The method of operating hot blast stoves having checker work and a combustion chamber communicating at one end with thechecker work, which consists in mixing gas and air externally of the combustion chamber to form amixture for producing complete combustion, introducing the mixtufts intqla fins oombustion chamber at that ms of sombhstion to pass from the other and thmgf which is remote from its connecend emf the combustion chamber into the 10 Eon withmhthe' checker WOIJhk, ignitingfsmfifi Kfimkr Work, substantially as described.

naming a mixture at e oint ii "Em- V fisrwca thereof into the combusfion chamber, 4 JAMES GORMAN cnmpletinlg" the burning of the mixture be- Witnesses force it reaches the exlt of the 'combusfi'on E. J. Bmn,- chamber and permitting the heated prod- A; Bnucm;

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