AN IMPROVEMENT IN BLAST SMELTING FURNACES
Year: 1884

page_text: COMPLETE SPECIFICATION.
I, THOMAS GILLESPIE, of Sydney, in the Colony of New South Wales, Gentleman,
do hereby declare the nature of my invention for "AN IMPROVEMENT IN BLAST
SMELTING FURNACES and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement:—
"
This invention has been designed for the purpose of preventing the lower end of
blast smelting furnaces becoming choked or clogged by the accumulated slag arising
froin the smelting of successive charges of ore. At present this is a very serious
difficulty as it is no uncommon thing for a furnace to become entirely choked or
"frozen" as it is sometimes called, in the course of a few weeks, necessitating an
entire stoppage of work, and considerable trouble and expense in removing such
slag and recommencing operations. Now I not only prevent the injury to the
furuace which arises froin the process of "freezing" but I enable it to work
continuously (until it requires repair from other causes) thus effecting a great
saving and affording a great convenience at one and the same time. My invention
consists simply in adding a close chamber at or near, and at a lower level than
the bottom of the furnace, and in providing a passage or tap hole from said
furnace into said chamber, so that as the ore melts it runs gradually through the
tap hole into the chamber without depositing any slag in the furnace. With the
melted ore there also enters through the tap hole a stream of flame which playing
upon the surface of the material in said chambers preserves it in a state of fusion.
In one of the walls of said chamber I provide two other tap holes, the upper one
being near the top and the lower one on a level with the bottom. The lower one is
closed until the charge is ready to be drawn off, but the upper one is kept open so
as to allow of the escape of the slag until the chamber becomes so full that regulus
instead of slag shews itself at the upper hole-then it is closed, and the lower one
opened to allow of the escape of the regulus which runs into suitable vessels provided
to receive it. When this has all run out the lower hole is closed and the upper one
opened as before, the operations of the furnace being thus continuous and without
interruption, except so far as is necessary to provide for the ordinary wear and
tear. In order to enable the workınan to close this upper hole it is necessary to
make a temporary vent in the upper part of such chamber so as to direct the
current of flame away from said upper hole. This vent may be made by simply
removing a brick from the roof or top of the chamber, and placing thereon a short
length of tubing for a flue.

page_text: I do not confine myself to any particular shape or size of my additional chamber
nor to any particular kind of blast smelting furnace to which it may be attached,
but I prefer to make such chambers oblong in shape, and I think it is desirable
that one or more of the tuyeres should be directed towards the tap hole in the
furnace which leads to my said chamber.
Having thus described the nature of my said invention and the manner of
performing same I would have it understood that what I believe to be new and
therefore claim as of my invention is :-
The combination with blast smelting furnaces of an additional or subsidiary
closed chamber for the reception of the fused. ore from said furnace through a
suitable passage so as to prevent the accumulation of slag in the furnace and to
admit of the separation of the regulus from the slag in said chamber substantially
as herein described and explained.
Dated this seventeenth day of October One thousand eight hundred and