IMPROVEMENTS IN THE MEANS AND APPARATUS FOR PURIFYING IRON, AND FOR REMOVING THE SLAG AND OTHER IMPURITIES FROM BLAST AND OTHER FURNACES
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by David Joy at the Office of the
Commissioners of Patents, with his Petition, on the 14th August
1872.
I, DAVID JOY, of Saltburn by the Sea, in the County of York;
Engineer, do hereby declare the nature of the said Invention: for
"IMPROVEMENTS IN THE MEANS AND APPARATUS FOR PURIFYING IRON, AND FOR
REMOVING THE SLAG AND OTHER IMPURITIES FROM BLAST AND OTHER FURNACES," to.
be as follows:
-
My improvements consist in a new method of purifying molten iron,
and removing the slag and other impurities from blast and other
furnaces and separating them, and I do this by drawing or carrying away
the contents of the furnace or a part of them by an induced or direct
current or blast of air, steam, or gas, or a combination of any of them with
or without water, such current acting as the vehicle by which the
materials are carried away and separated the one from the other. And
such current either direct or induced is proportioned in its composition,
volume, velocity, and form so as to carry away the lighter material as the

page_text: slag refuse and gaseous products, and to drop through it all metal so
freed from impurity. Thus while the metal is dropped the slag and such
refuse is projected to a distance and separated, and the gasious products
as sulphur, &c. are carried away with the steam and separately collected,
and the machinery I employ consists either of a simple form of ejector
producing a powerful induced current which is placed over or near the
runner of slag or metal, in such position as to receive the slag or metal
as it runs from the furnace, and drawing it up to disintegrate it and
project it to a convenient distance, the steam arising from the operation,
with which much of the phospherous and sulphur from the slag will
combine being drawn off from the tube projecting the slag, and will be
condensed to deposit the sulphur, &c.
When the slag is drawn off the same action will be applied to the
metal drawing it off from the furnace and passing it through the ejector,
where it will be disintegrated by the powerful current therein, and by
mixture with the steam will be cleared of the sulphur and phosphorous,
which will be carried away as before, and afterwards collected.
To obtain a powerfully disintegrating action in the ejector I make tho
blast of steam, air, or gas (which by preference should be annular) to
converge early within the tube, the point of convergence governing the
disintegrating action. And if I require to assist the delivery of the
furnace I place the ejector in direct communication with the inside of
the furnace by covering over the runner of metal or slag, so causing the
ejector to exert an exhausting action on the furnace. Or to remove
slag only from the furnace I employ a direct current or currents of air,
steam, or gas, discharging under the runn of slag or in such position as to
receive the slag which shall run into it, and be carried as if by a solid
travelling spout by the mere force and body of such current or com-
bination of currents, such current or currents however being proportioned
in figure, force, and volume to the weight and quantity of slag to be
carried, or the distance it is to be projected so as to carry away all slag
and refuse, and to allow any metal passing away by the slag runner to
fall through and be saved. And when required I use a combination of
currents as above described or a succession of such currents, that as the
motion produced by one fails it may be taken up and perpetuated by
another, and so on. And I use guide plates or pipes around the currents
to guide or deflect the motion of the slag as required, such guido plates as

page_text: well as all other parts in close proximity to the slag and likely to be
damaged by the heat thereof being hollow and supplied with water. And
I use a part of the heat from the slag passing it through a hollow
runner supplied with water to raise the steam, or a part of it, for pro-
ducing the blast..