IMPROVEMENTS IN THE SMELTING AND MANUFACTURE OF PIG IRON
Year: 1874

page_text: PROVISIONAL SPECIFICATION left by James Cane Coombe at the
Office of the Commissioners of Patents, with his Petition, on the
18th April 1874.
I, JAMES CANE- COOMBE, of 18, Lesley Street, Barnsbury, in the
County of Middlesex, Chemist, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE SMELTING AND MANUFACTURE OF
PIG IRON," to be as follows:-
These improvements consist in the use and employment of purified or
nearly pure materials in the smelting furnace. A good pig is the
foundation of all successive operations, be the requirements whatever it
may, from wrought or soft iron to steel of all qualities.
My Invention is to submit the raw materials, coke or ore, to such a
purifying process that on withdrawal from the furnace or clamp all
sulphur, phosphorus, arsenic, silicon, and the like shall be completely
expelled, and to do this I make use of certain well known materials,
namely, hydrochloric acid, chlorine, carbon, highly subtilized and nitro-
genized steam, water, and atmospheric air.

page_text: In making pure coke I purpose whatever form of coal may be
employed in its production that it should be submitted to distillation, so
that the gas as it issues from the retort is collected and utilized for an
after process.
Now by my present improvements I recommend that when the a
carburetted hydrogen ceases to issue from the retort that the valve con-
nected with such issue should be closed, and that whilst and during the
remaining of the coke in the retort the same shall be in a highly heated
or red-hot state. Steam in combination with hydrochloric acid gas or
when silicon dominates chlorine gas in combination with carbon shall be
forced into and through the said heated coke, by which means all or
most of the obnoxious constituents are driven off and may be allowed to
escape through another suitable tube and tap.
Sometimes it is found more convenient to burn the coal in clamps and
thus procure a coke. When such is the case I purpose when the mass
is in a highly heated condition and most of the volatile matters have
escaped, to sprinkle over all a mixture of hydrochloric acid and water
rather largely diluted. This is a very efficient mode of getting rid of the
sulphur and such like constituents.
As regards the ore it is desirable to roast it in some suitable vessel,
kiln, or furnace, instead of clamping it as is usually done, but should it
be found more convenient to resort to the open roasting process, then I
purpose the frequent distribution (in the form of sprinkling) of diluted
hydrochloric acid amongst the heated mass, and especially when it is at
and above a red heat. I prefer however to roast the ore in a kiln or
some other suitable furnace or vessel, and when all that is possible of the
volatile constituents have been driven off I purpose to pass through the
heated ore the same constituents that were employed in purifying the
coke.
As the object of my Invention is to ensure purity of result by purity
of means no lime, limestone, or flux indeed could be rendered available
unless it was perfectly free from obnoxious constituents. As a high
temperature is necessary for economically and efficiently working a
cupola, I purpose to utilize the gas obtained during cokeing the coal by
burning it with atmospheric air similar to an oxyhydrogen apparatus,
and which can be made to play at any part of the furnace by means of
suitable apertures. Or the gas may be passed by itself or in combination

page_text: with some form of nitrogenized carbon into and through the whole
heated mass, the gas will of course have to be previously purified by
passing through the usual purifying materials.
My Invention further consists in the manufacture of what I term
smelting coke, and which enables me to utilize the gaseous matters
during the process of smelting, and also in the employment of chloride
of lime mixed with some kind of carbon as a purifying flux, and which
I introduce with the broken or pulverized ore at the top of the smelting
furnace, also I sometimes saturate the coke I employ with a diluted
solution of hydrochloric acid, which said coke I likewise introduce at the
top of the smelting furnace when the furnace is in full blast. As the
acidulated coke and the chlorinated ore become heated the purifying
agents begin to act, and by the time the mixed materials descend to the
reducing part of the furnace most and in many cases all the con-
taminating constituents of the ore and the coke become dispersed and
volatized.