871
Deville and Kjrchoff, of the increase of luminosityof flames when burnt under great pressure; viz., thatthe temperature of the flame is thereby increased.
Alterations of temperature produce changes inspectra, and I think it will be found that thisBessemer spectrum, or at least that part of it whichis due to carbon, is simply the spectrum of carbonicoxide of the particular temperature at which it isburning at the mouth of the vessel.
Spectrum Observations Show Analysis of the Gas Shows
Carbonic acid
1st stage, O' to 4' Faint continuous spec- I evolved, but littletrum. No actual flame, f or no carbonicJ oxide.
(t
4' to 8'
Sodium, potassium, andlithium lines appear.Towards the close,occasional flashes ofcarbon lines,.
1 Carbonic acidstill given off, withbut little carbonic^ oxide. The tem-{ perature certainlyrising, and causingthe volatilizationof alkaline metals.
2nd stage, 8' to 10' Dense flame, bright car-bon lines in red, blue,and green fields,....
Carbonic oxideevolved in quan-tity, and burning•at a high tern*perature at themouth of the con-J vertor.
10' to 14'
Bright green carbonlines, more distinct,
1
Carbonic oxidemuch increased inquantity.
If'to end. Carbon linea brighttill close, when theysuddenly disappear,
1 Carbonic oxide! still being evolved| up to end of re-J action.
It may be interesting to compare the compositionof the gas, during the latter part of the blow, withother available gases met with in iron-works. I haveselected as blast furnace gases a sample of gas froma Cleveland furnace, by I. L. Bell, and one from aBessemer furnace, by William Crosslev, and haveadded two samples of gas from Siemens’ producer,at Dowlais, which I have had occasion to analyze—
TABLE VII.
Siemens'Producer Gas.
BessemerConvertormean com-position ofgas duringlast half ofblow.
AskamFurnace onBessemerPig.
No. 1.
No. 2.
Carbonic acid,...
4*3
5-2
1-34
17-30
8-36
Carbonic oxide,..
25*6
24-4
31*11
25-2
34-97
Hydrocarbons,...
2-8
traces.
—
—
—
Marsh gas,.
1‘6
2-4
—
—
—
Hydrogen,.
—
8-6
2-00
•1
2*16
NitrogeD, &c.,.. .
65*7
59-4
65-55
57-4
54-51
ioo-o
100*0
ioo-oo
100-0
100*00
cent, of carbon, we find that a Bessemer works,using only 1000 tons of such pig per week, is wastinga quantity of fuel equal to 2.31 tons pure carbon, orsay 25 tons coke.
Now, I would suggest that it is possible by simplearrangement to collect the gas and pass it underboilers, where it would save its equivalent of coal.The large body of flame is not wanted for anypurpose. True, the workman now depends uponits indications to afford liim the means of judgingwhen the blow is completed; but the spectroscopewould do this, with greater accuracy, with a fractionof the gas which now roars from the convertor.
The nature of the gases evolved during the blowwill, of course, vary with the quality of the ironused; but as it is not possible to use iron with muchless than 3 per cent, carbon, the quantity of carbonicoxide evolved cannot be much less than that foundin the foregoing analysis; and I believe that what-ever may be the nature of the iron, the generalresults would be the same.
Comparison of amounts of silicon and carbonoxidised—
TABLE VIII.
No. 1. ■
.72-91
\ Carbon,.
.27*09
“ 2. ■
( Silicon,....
} Carbon,.
“ 3. ■
f Silicon,..
\ Carbon,.
“ 4. ■
.39*58
\ Carbon,.........
“ 5. -
| Silicon,.
. 4*24
^Carbon,. ,
( Silicon,......
Carbon,..
100-00
100-00
ioo-oo
100-00
ioo-oo
100-00
Comparison of amounts of carbon oxidised to CO
and C0 2 —
No. 1. ■
18
to
to
CO,.
co 2 ,.
- 100-00
“ 2. -
i
1 C
to
to
CO,.
- 100*00
“ 3. -
JC
i 0
to
to
CO,.
co 2 ,.
. 35-54)
. 64-46/
■ ioo-oo
“ 4. -
JO
I 0
to
to
CO,.
C0 2 .
. 15-46 /
■ ioo-oo
J c
to
CO,.
■ ioo-oo
[o
to
. 7-28/
(0
to
CO,.
■ ioo-oo
10
to
C0 2 ,.
. 413 /
. • . C to C0 2 = 259-81C to CO = 340 19
600-00
It will be seen from these analyses that the gasfrom the Bessemer convertor, during the last halfof the blow, is really of as much value as any gasmade purposely, or incidentally, at an iron-works.This is a most important fact; and if we considerthe amount of fuel thus going to waste, the questionnaturally suggests itself whether it cannot be madeavailable.
If we assume that, during the latter half of theblow, two-thirds of the total carbon in the pig isburnt, and take the melted iron to contain .3 j per
That is, Jgths of the total cirbori is oxidised to C0 2 , andJJths to CU.
These results have since been corroborated by M.Adolf Tamm, in the Jem Kontorels Annulerior 1875,on “The Chemical Composition of the Gases emittedfrom the Bessemer Convertor during the Blow.”The experiments were made at the WestanforsBessemer Works, Sweden , the iron used beingcharcoal pig made at the same works, the analysis ofwhich, and of the steel produced during the A series,were given as follows (Table XI.).