IMPROVEMENTS IN " FURNACES FOR REDUCING AND SMELTING CERTAIN DESCRIPTIONS OF ORES
Year: 1882

page_text: LETTERS PATENT to John Imray of No 28. Southampton Buildings Chancery
Lano in the County of Middlesex for an invention of "IMPROVEMENTS
IN
"
FURNACES FOR REDUCING AND SMELTING CERTAIN DESCRIPTIONS OF
ORES A communication to him from abroad by James Cosmo Newbery,
John Lister Morley and Barry Cleveland, all of Melbourne in the Colony of
Victoria
COMPLETE SPECIFICATION filed by the said John Imray at the Office of
the Commissioners of Patents on the 19th August 1882.
"
JOHN IMRAY of No 28 Southampton Buildings Chancery Lane in the County
of Middlesex, "IMPROVEMENTS IN FURNACES FOR REDUCING AND SMELTING
CERTAIN DESCRIPTIONS OF ORES A communication to me from abroad by
James Cosmo Newbery, John Lister Morley and Barry Cleveland all of Melbourne
in the Colony of Victoria
This invention consists of certain improvements in furnaces for reducing and
smelting metallic ores especially those which form oxides or compounds that may
be reduced by heated charcoal, such as ores of antimony, bismuth, copper, tin
and zinc.
One part of the invention relates to the production of oxides from sulphides
arsenides, and other oxidisable ores by treatment of the raw ore on a hearth.
When the ore is easily fusible such for example as sulphide of antimony the method
of treatment differs from that of ores that are not readily fused. In the case of
sulphide of antimony the hearths in use usually have a solid bed with a tap hole
in some convenient position for drawing off the fused sulphide, which is then
smelted in a crucible or furnace. According to this invention the bed of the hearth
is not solid, but has holes or perforations all over it which allow the fused sulphide
to pass through them to a solid bed underneath where the sulphide is converted
into oxide or if desired may be drawn off as crude sulphide. When the ores

page_text: do not fuse readily the oxide may be made in any of the ordinary ways
now in use.
Another part of the invention relates to the conversion into metal of the
oxides whether natural or artificial. This is accomplished by smelting them in a
furnace so constructed that the draught is downward through the oxides in process
of smelting, and through the carbon material used in the process.
The furnaces may be so constructed and arranged that the heat from one fire is
utilised for liquating the ore, perfecting the oxidation, and producing the metal, as
may be understood on reference to the accompanying drawings. Fig 1 is a
longitudinal section of the furnace, Fig 2 is a plan, Fig 3 is a cross section of the
reducing part of the furnace on the line a a (Fig 2) and Fig 4 is a cross section of
the liquating or oxidising part of the furnace on the line b b (Fig 2). A is the fire
place, A' the fire bridge, B B are tubes or cylindrical chambers made of fire clay or
other refractory material and closed with caps B¹ B'. B is the bed of this part of
the furnace, B is the flue from the bottom of the reducing part of the furnace into
the precipitating chamber or flues. and B the entrance into the oxidising chamber.
C is the perforated hearth of the liquating chamber, and D the solid bed
underneath. CC are feeding doors, and cleaning out doors. D¹ is also a
cleaning out door, and D' the escape flue to the precipitating flues or chambers.
The mode of operation is as follows. The fire having been lighted in A, and the
necessary heat having been attained, the hearth C is supplied through the doors
C' C¹ with the ore to be treated and the doors are closed. The tubes or cylindrical
chambers B are then charged with the oxide to be smelted, and with the necessary
carbon in substantially the following way. First, there is a thick layer about one
foot deep of the carbon material (such as wood charcoal) at the bottom, then a layer
of about six inches of oxide, and then another layer of about two inches of carbon
and so on until the tube is filled, so as to provide sufficient carbon to reduce the
oxide as is well understood. As the contents descend they are replaced by fresh
oxide and carbon in alternate layers following similar proportions. The caps of the
tubes are left off until there is no more material to treat, when they are put on, so
as to prevent escape of injurious gases and unnecessary waste of material. The hot
products of combustion from the fire A play around the tubes B then pass
through B into the liquating chamber. When fusible sulphides are being treated
they are fused and run through the perforations of the hearth C to the solid bed D.
The hot gases then pass over the solid bed D and finally through the outlet flue D³
to the precipitating flues or chambers which being of the usual kind are not shewn.
As the heated current passes over the solid bed D it carries with it the oxide that
has been formed thereon and in order to facilitate the production of this oxide the
door D'is opened sufficiently and as often as may be required to admit air or heated
air may be supplied by pipes to the bed D.
The oxide in the tubes B becomes reduced by the heat and the resulting metal
passes through the carbon at the bottom to the solid bed B whence it is run
through the tap hole B5 into a suitable receiver. Combustible gases or liquids, such
as hydrocarbon, hydrogen, or carbonic oxide may be used more or less as a
substitute for the solid carbon in the tubes, so long as a thick layer of carbon
remains in the bottom of each. .
Having thus described the nature of the said invention, and the manner of
performing the same as communicated to me by my foreign correspondents, I
claim as improvements in furnaces for reducing and smelting metallic ores,
especially those which form oxides or compounds that may be reduced by heated
charcoal
First. Constructing the hearth on which the ore is first treated with holes or
perforations through it so as to allow the fused ore to fall through substantially as
herein described.
Second. Combining with the perforated hearth a solid bed underneath on which
the fused ore is oxidised, substantially as herein described.

page_text: Third. Constructing the reducing chambers as tubes or cylinders arranged so that
there is a downward draught through the material under treatment substantially as
herein described.
Fourth. The construction and arrangement of combined furnace chambers,
substantially as herein described with reference to the accompanying drawings.
In Witness whereof I the said John Imray have hereunto set my hand and
seal this seventeenth day of August in the year of our Lord One
thousand eight hundred and eighty-two.
JOHN IMKAY (LS.)