USRE11925E - nesmith - Google Patents

Description

Heissued Aug. 6, IQOI.

J. wg NESMITH. BLAST FURNACE. (Appiininn med septh 22, 1900.)

3 Sheets Sheet 2.

No. H,925. Reissued Aug. 6, |901. J. W. NESMITH.

BLAST FUBNAGE.

(Alplntion filed Sept. 22, 1900.)

3 Sheets-Sheet 3 UNITED STATES,

u. T" i j l a PATENT OFFICE.. l

IRON VORKS COMPANY, OF SAME PLACE.

., BLAST-FURNACE.

,SPECIFJICTIONforming part of.`Reissued Letters Patent 1\l'o."11,i925,` dated August 6, 1901. original'Nauw/tijuana october lenses. Application for reissue tutti spemter 22,1900. santi no. 30,775.

T 1till whnz/ it may ef'ftcejn.- Bejitkno'w'n that I, JOHNW. NESMITH, a oit'i'zenot `the United States, residingat Denlver, Colerad o', ha ve invented certain new and 'useful Improvements in BlastfFurnaceacf which the following is a specification.

This invention is an improvement in blastfurnaces applicable particularlyto the class y of Water-jacketed blastfnrnaces wherein the xo'ores'hof lead,fsilver, copper, and gold are.

slnelted. p V

There are localities Where there is a scarcity of Water and ditlicultys had in getting enough for cooling theivaterfjackets of furnaces rin t 5 the usual Way,`and even vwhere the Water is caught in" ponds ontanlgs to be used over and overagain there is often still a' shorta'ge'on account ofithe Waste.` Inother'places. the necessa1y-"\vater is purchased fr om the city zo" 'Watr companies at ,great cost. l' n I-tfifs thfe primary object of my present invention to: provide a'construction adapted to eect a very great saving of water; but the y myention alsojncludes other and important fea'tures' of construction, all a's hereinafter described:y l

In carrying outl 4my inventionadtgantage is taken offthe latent heatof ,steain v `vhich is nine hundred andsiXty-six heat units-'fthat 3o `is to say, one pound of Water at 212 fFahrenheit absorbsl nine yhundred and sixty-six heat units in evaporating to steam at the saine in# dicated or sensible te mperatureto wit, 212". Allowing the'water tobeisupplied tothe jacke'ts at 62 and' discharged at boilingto Wit, 2121-thei-e has been absorbed by earch pound of. Wateri but 150, or ene hundred and fifty heat unit-sywhich isy allvthat is possibleto get Where' Waterr instead yof steam 'is discharged froin'the jackets. A.If evaporated to steam froni'i'nitial temperature of 62, We have thus for one pound of' Water one hundred and fifty units `t'o boiling at 212(J plus nine hundred`V and sintysix units inevaporating to'steam still at 212 indicated temperature, which equalsjeleven hundred "and" sixteen heatl unitsthat'i's to say, each pound of water has gainednilne hundred and sixty-six units of heatitvithoutthe jackets becoming any hot- 5o` ter'than 'as though dischargingfboilingwater.

The proportion f gavin 'in coolingeilci'eney or hund red and sixteen.

tion, partlyin section.y

Water saved is then nine hundred and sixty six heat units,-or nine hundred and sixty-six plus vonenhundred and fifty equals eleven 1 Thus it vwill be seen 55 that 7.4.4 times as much Water is used-if -discharged boiling from the jackets as would be used if Y.the Water is evaporated and dischargedas steam, with the further result that the jackets get no hotter in cvaporatingthe 6o vWater to steam than by simply discharging the .boilingwater from them.

In other Words, I use but atrie more than one-eighth the,`

amount of water by evaporating it than would have been used by discharging it boiling from 6 5 Athe j ackets,and as iu common practice water is but seldom dischargedA from the jackets'as hot as Zlio the amount required'for evapora- -ticn will fall beloWone-eighth that usually' used for cooling and Will have kept the jaek- 7o ets at the same temperature in the one case` as in the other.

In the drawings, Figure lisan end eleva- Fig. 2 is a longitndinal elevation, partly in section, of an ordinary silver-lead blast-furnace, showing'the improvements ot' the present invention. Figs.. 3, et, 5, and 6 show details of the Water-jacket; I Fig. 7, details of the safety-valse; Fig-8, de-

tails of the valve controlling the blast to the `8o twyers, and Figs. 9A and lO show sectionsof thefdrumand bustle-pipe and the pipe connections therewith. n A In carrying out my invention'practicallyI prefer to connect ,all the sections onjackets by means of pipes to one or more tanks, reservoirs, or drums. A simple'and. eticient; means'is to connect the jackets by means of n suitable pipes to a horizontal drumBl on each `side of the furnace, as shown. s The jackets 9o and pipes are thus kept full of Water, and the Water-level is maintained near the center o f the drum B and the separat-ion of steam takes place in the drum, the `escap e-pipeb at the end leading the steam'aivay to the open air. All V95 the jackets are conneetedwith thebottom of the drum, andv thus no one of them can run short offWatj-er by'any possibiiity unlessthey all do so; A very compact and complete .a1--

rangement is, as shonfn, toy `place" the eva-poloo rating drums B inside the bustle or blast pipes A', whichlatter must ofcourse bel-arge enough to accommodate the drums B, with ample space around them to vallow free pas. sage of the. air-blast. By this means the drum B, being exposed to the air-blast within' denser', and much of the steam is condensed :backinto water inthe drum and thus saved,

-while'heat absorbed by the air-blast goes .forward into the furnace. The advantage of the warmair blast in the much-.improved working of a furnace', though itsheat may not exceed 200 Fahrenheit, is by far greater than can'b'e accounted `for by the caloric value ofthe heat thus saved and returned to the furnace.

Cold water lenter-s the evaporating-drums Bjatthe'bottom-through the pipes g and YHows down into'thewater-jacket sections W -through the pipeslv, Rigs. 2 and 10. -The cold waterflows'constantly downward through the pipeso, being heavier, while the heated expanded water. flows upward from the jackets lT hrongh-A the pipes c and the curved pipe 3 the hot-water-dis'charge pipes c,

vand is discharged, vas, shown, at the surface .ofthe water '.in the drum B, where evaporaconnection i.0.be lalwaysfkept between the drum` and zthe jackets, notwithstandingexpansion'or change fromany cause vin relative position. These hot-water pipes from'the jackets terminate* inside the drum in short sections of c urvedfpipe, riveted or bolted i jackets --to .the `surface"of -thewater in-the.

permanently to` the 'insid'ejof the drum B. These short sections ware vfor the purpose of delivering the'hotl discharge-water from the 'dru mwhereevapor'ation takes place. At the 'endet thev..dum, Figs'lfand 2, I arrange a T b fwith a discharge-pipe b for the steam. Any surplus of water4 passes through and --falls downwarilat-ul and vis carried away by ajsu-itable pipe.

*The 'jairepipe' enters the-bu-stlefpipe A at any convenientlpointand passes ouinto Athe severaljacketmw through branch vpipes p, Figs. ljand '2,'co'nnectedl bysuitablevalvev chambers 0,'fri'veted tothe bustlepipe A. These. valve .-'chambers' are supplied with clack valves;4 j, Vhaving stems fand' handles `(not shown) v'conveniently opened and closed by hand.. vThe brauch pipes'p-connect the valve-chambers o with valve-boxes wfonthe jackets W, andeachvalve-boxw is supplied with a clack--valve e, 'which opens inward or downward' by-'its 'own 'weight when the blower stops or'*whe.n thev clack'- valve'f is closed, stopping the blast and relieving it of pres? sure;.'but when the valve f isopened and -blast-pressure is on the Avalve e. closes and theblast passes on into the back chamber 2 of the jacket, and thence through the twyer and into the furnace. The clack-valve e thus .forms a safety-valve to allow any inflammable which the air is blown on its way to the furnace, the one on the inside, y, carrying the water... It vconsists simply in theaddition of anair-chamber attached von the backs of ordinary jackets. The air-blast passes from the bustle-pipe A into the chamber a through the pipe p. The twyer r is through the water-jacket and is open tothe. air-chamber a, so that air blown into the chamber is free to pass into the furnace. A hole -s, opening through the outer wal-l ofv the air-chamber, affords access to the twyer. This opening is closed with a taper plug -t,which can be removed'k instantly for barring the twyers when necessary, and the plug has asight-hole fu, through it. This construction of ljacket simplifies the blast-pipe connections very much and dispenses entirelywith the twyerpipes and canvas bags in common use.

- `TViththis vconstruction the furnace may be operated by evaporation in whole or in'part or entirelyby overflow, as `may be desired.

kThe construction presents a very effective arrangement for both air and .-water. The jackets are always supplied with water, so long as any have it; -all being alike connected with the bottom of the drum B by the downpipes fv, and thus the temperature is alikein all. The blast enters the furnace at the temperature of the discharge water, lwhatever that may be, by reason of its exposure to the heated .exterior surfaces of the drum B and chambers z ofthe jacket-sections.

' lThe construction is perfectly adapted not only to the-'evaporation system, but equally tothe overflow system, no change whatever being necessary-when changing fromone system to the other. As the water-supply runs short evaporation at once begins automatically and continues. to compensate for what- .ever shortage `there may be until thevsupply dwi-ndles away to one-eighth the ordinary -V supply necessary for overlow when discharging boiling water, and at that point all is evaporated. and the supply must Vnotrun lower. There isno disadvantage whatever in evaporating the ,whole .necessary for cool- 4ing the jackets, while there is much advantage in the system as pointed out above. A

The'heat of jackets will not bevariable4 'when evaporating or infany' case where this system is used,- as it is by the common 'method -of discharging water whensthesupply turned on .them isvaried," 'and it is in fact no uncommon thing. to see jackets dischargingwater AIOO below 140 Fahrenheit in thejordinary methods of supplying water to them.. Sueh changing from hot to cool exerts severe strains lon the jackets and a chilling iniiuence onA the furnace, appreciably retarding its proper action,thickening the chilled coating of smelted material or slag on the tirer-.surface of the jacket; and reducing furnace area'to an extent. v

It is the experience of every smelting-furnace metallurgist or lforeman that every now and again the coating of slag and other fusedmaterial which chills and collects on the inner face of the jackets will thicken to two or three or four times the usual or normal thickness and will then let go and slide down, leaving the jackets bare, to again collect a coating of fused ore and slag. This makes an irregular Working ot' the furnace. It is caused chiefly by changes in temperature. of jackets, brought about by frequent change in amount of Water being supplied to them. In the present system irregularities of this kind are avoided to a great extent, as the jacket temperature is maintained consta-nt.

I claime- 1. In combination in a blast-furnace, a series of independent Water-jackets,l a drum or .tank open to the atmosphere forming an elevated reservoir, a water-supply thereto, a series of pipes leading from the drum directly to said series of jackets, and a second series of discharge-pipes leading directly from the jackets to the drum, substantially as' described. .Y

2. In combination in a blast-furnace, a se'- ries of independent Water-jackets, a drum or tank, a water-supply connected with said drum near the bottom, a series of pipes leading from the drum directly to s aid jackets,

and a second series of discharge-pipes leading from the jackets upward to the drum, said discharge-,pipes being extended upward within the tank above the water-supply, substantially as described.

3. In combination in a blast-furnace, a series of independent Water-jackets, a drum or tank forming a reservoir, a water-supply thereto, a series of pipes leading from said tank directly to said series of jackets, a sec- .ond series of discharge-pipes leading directly from the jackets to the drum, and a single discharge-outlet serving to discharge both Steam and the overflow from the drum, substantially as described.

4. In a blast-furnace, a series of independent water-jackets having each an independent air-compartment in rear thereof, substantially as described.

5. In a blast-furnace, aseries of independent .Water-jackets,4 each water-jacket having an independent air-chamber in rear thereof, a passage forthe air through the Water-chainiber, and an air-supply for the air-chamber,

substantially as described.

G. In a blast-furnace, a series of independent Water-jackets j having independent aircompartments in vrear thereof, a series of airpipes connecting with the series of independent air-chambers, a bustle-pipe in connection with the series of air-pipes, and intermediate valves between the bustle-pipe for controlling the air to the series of pipes,substantial1y as described.`r i A 7. A blast-furnace, a series of independent water-jackets and a series of independent airchainbers in rear of the water-jackets, a partitiondividing the water and air chambers, j

a bustle-pipe, a tank Within the bustle-pipe having feed and discharge connections With the `Water-jackets and a series of air-pipes between the bustle-pipes and the air-charnbers with discharge-openings from the airchambers, substantially as described.

8. In combination with a water-jacketed blast-furnace, an evaporating tank or reservoir having awater-space, asteam-space and a steam-outlet, one or more hot-water-discharge pipes connecting the Water-jacket with the tank and one or more supply=pipes connecting the tank with the water-jacket and an inlet-pipe for the supply of water to .the

tank to compensate for that lost by vaporiring into steam from the surface ofthe Water therein.

9. In combination with a Water-jacketed blast-furnace,a` tank or reservoir having a maintained. Water-level With a steam-space above the Water-level, pipe connections between said tank and jacket for causing a free circulation in the jacket, the induction and eduction pipes connecting with the said tank at different elevations so as to secure the discharge of the hot water at or near the top of the `Water-level and the feed of the cooler Water from near the bottom of the tank, a

source of Water-supply for the tank and means for maintaining a constant level therein, substantially as described.

10. In combination,` a blast-furnace having a plurality of independent water-jackets and a tank or drum elevated above the jackets with pipe connections to the jackets to keep them constantly supplied with Water, a Water IIO and steam outlet located below thetop of the drum whereby a steam-space is provided above the water, the connections with the jacket being such as to discharge the hot water at or near lthe top of the'Water-level of the tank or drum at the point of least pressure, a steam-discharge from said tank and a suitable Water-supply.

f .roi-1N W. rfEsMlTI-i.

Witnesses JAS. TALLEY, A. L. HIcKoK.

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