A CERTAIN IMPROVEMENT IN, THE ART OR PROCESS OF SMELTING IRON ORES
Year: 1838

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
SANDERSON, of Sheffield, in the, County of York,. Steel Manufacturer, send
greeting.
WHEREAS Her present most. Excellent Majesty Queen Victoria, by Her
Royal Letters Patent, bearing date, at Westminster, the Eleventh day of
October, in the second year of Her reign, and in the year of our Lord One
thousand eight hundred and thirty-eight, did for Herself, Her heirs and
successors, give and grant unto me, the said Charles Sanderson, Her especial.
licence, full power, sole privilege and authority, that I, the said Charles
Sanderson, my executors; administrators, and assigns, or such others as I,
the said Charles Sanderson, my executors, administrators, or assigns, should.
at any time agree; with, and no others, from time to time and at all times.
during the term of years therein mentioned; should and lawfully, might make,
use, exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed; my Invention of "A CERTAIN IMPROVEMENT IN, THE ART OR PROCESS
OF SMELTING IRON ORES;" in which, said Letters Patent is contained a proviso
obliging me, the said Charles Sanderson, by an instrument in writing under my
hand and seal, particularly to describe and ascertain the nature of my said,
Invention, and in what manner. the same is to be performed, and to cause
the same to be enrolled in Her Majesty's High Court of Chancery within
six calendar months next and immediately after the date of, the said in part
recited Letters Patent, as in and by the same, reference being, thereunto
had, will more fully and at large appear..

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Charles Sanderson, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, is particularly
described and ascertained in and by the following description thereof, reference
being had to the Drawings hereunto annexed, and to the letters and figures
marked thereon (that is to say) :-
The object of my Invention of a Certain Improvement in the Art or Process
of Smelting Iron Ores is, to separate the scoria, slag, or other earthy or
extraneous matters from the metallic part in a better and more economical
manner than is commonly practised in the smelting of iron ore, and consists
in a novel or improved process or manner or method of treating or operating
upon the ore, whereby I am enabled to separate and remove the scoria or
carthy matters contained therein from the metallic parts without the neces-
sity of melting both the metal and scoria, or bringing them both into a fluid
state, and then running off the fluid iron from the scoria or slag, as is the
usual practice in the blast furnace (that is to say): I treat and operate
upon the ore in such manner that I reduce the scoria or other extraneous
matters contained therein to a fluid state, so that the same will separate from
the metallic parts, and run off, leaving the metal without being melted into a
fluid form, the metal being left after the scoria or slag has separated from it
in a sort of pasty consistency, and in a fit state to be removed from the
furnace, and applicable to various purposes, either to the making of bar ironi
by puddling, or to be refined or melted and cast into pigs, or any other form
required:
Having stated in general terms the nature of this improvement, I will.
proceed to describe the method of carrying my Invention into effect, first
referring to the usual manner of operating upon iron ore, to shew difference
between this and my improved process or manner of treating the same: In
the ordinary operation of smelting iron ores, the ore, after having been roasted;
is placed, together with the flux and fuel; in a furnace, and submitted to the
action of powerful combustion, supported by a continuous blast of air. The
scoria, slag, and other extraneous matters, as well as the metallic parts,
thereby become melted into a fluid state, and descend to the lower part of the
furnace. The fluid metal, being the heaviest; falls to the bottom, with the
fluid scoria or slag lying upon the top of it, which runs off from the métal as
it becomes melted, through a hole made in the furnace for this purpose,.
the fluid metal being run off at a lower aperture into "pigs," or other forms,
as required. It will thus be seen that both the metal and scoria or slag
are melted together, and both rendered so fluid that the metallic parts

page_text: percolate through the scoria and fall to the bottom of the furnace; whereas,
by my improved mode or method the scoria or slag only is rendered fluid, and
runs away from the metal, leaving it in a kind of pasty consistency, ready to
be used for various purposes. And I will now proceed to describe the manner
of carrying this improvement into effect, referring to the Drawings hereunto
annexed (that is to say): I take ironstone of the argillaceous description of
iron ores, or any other description of iron ores, be the same rich or poor in
metal, or containing more or less of any earth or substance foreign thereto
(commonly called the matrix). These ores I subject to the usual process.
of calcination or roasting. The ore is to be broken small, so that it will pass
through a riddle or sieve of about half-inch mesh, and, thus prepared, is to be
mixed with a carbonizing material, such as charcoal or coke dust, or any
other convenient substance which will produce a similar effect. The quantity,
may be varied according to circumstances, but I consider the best proportion
to be about ten per cent. (or to every one hundred pounds of broken ore
add ten pounds of charcoal or coke dust). If the ore in its natural state
contains earths in such proportions as will produce or cause their fusion
at the lowest temperature at which earths so compounded do fuse, then no
flux will be required to be added; but if the ores contain or are composed
of earths which do not melt at the lowest temperature, or which are difficult
of fusion, or even if the earths are fusible, but not in the best proportions to
effect their separation from the iron without the necessity of fusing it also,
then a quantity of flux is to be added and combined with the ore and coke
dust in such proportions as will form a mixture wherein the earthy parts
shall be most easily melted, my object being to effect a complete fusion of the
earthy matters or matrix of the ore at as low a degree of heat as possible,
while the metallic parts remain unmelted or not in a-fluid state. The ores or
mixture of ore and flux, being prepared, is placed in a roasting furnace of
any convenient construction, for the purpose of driving off the moisture and
rendering it perfectly dry and hot, and in this state it is removed into a
reducing furnace of any convenient construction. It is to be acted upon first
by a low heat, until it has become de-oxidyzed, after which the heat is to be
gradually increased until the ore with the flux begin to agglutinate and sink
into one mass. The heat is then to be increased more rapidly until the
scoria becomes fluid, when the heat is to be kept up equally, and the "cye"
or "slaghole" at the bottom of the furnace opened to allow the scoria to run
off as it becomes fluid, leaving the metal behind, except any small portion
which may have combined with the flux, scoria, or slag, during the operation.

page_text: Should the ore contain matter deleterious to the production of good quality
of iron, such as sulphur, arsenic, or phosphorous, I propose to add such
substances as are known to counteract these defects with the ore and flux
in the reducing furnace, with a view of removing wholly or in part these
deleterious substances, and thereby improving the quality of the iron produced.
It will thus be evident that although the metallic parts become converted
into metal intermixed: intimately with scoria; and also that it is in a pasty
state of greater or less consistency, according to the degree of heat applied,
yet the metal is never in a state of comple. fusion. Thus all the desired
effects which are produced in the common blast furnace are produced in this
furnace by my improvement, excepting that the metal is never reduced to à
fluid state; and these objects are effected without the necessary use of an
artificial blast, and at a degree of heat much lower than required in the
ordinary blast furnace. The metal, being thus separated from the scoria,
is to be removed from the furnace by tongs, or in any other convenient
manner. I would here remark, that the above effects may be obtained by
various modifications of furnaces; therefore I wish it to be understood that
I do not intend to confine myself to any particular form or construction
thereof, and I have shewn in the accompanying Drawings. only such an
arrangement as I have found to answer the purpose, and which will serve to
illustrate the manner of carrying my improvement into effect..
i
Figure 1 is a vertical section of a preparing furnace, wherein the ore is
roasted and carbonized by mixing it with the carbonaceous substance, and
acting upon them by heat, the same as in the upper- part or chamber of the
common blast furnace.
:
Figure 2 is is a top or plan view of the same; and Fig. 3, a horizontal section
taken in the line a, b, Figure 1.. The furnace is divided into two chambers
A, B, for receiving the ore or mixture of ore and carbonaceous materials,
which chambers are heated by one fireplace D, and separated from:.each
other by the flues and hot air chambers C, leading from the fireplace to: the
chimney E. The furnace is represented as circular, but it may be of any
other figure, and is constructed of brickwork and iron in the usual manner
of erecting such works. F, F, is the main arch of brickwork, upon which
the whole structure rests.. The outer chamber Ais.open at the top part for
the admission of the ore, or ore and carbonaceous matters, and is furnished
with doors G, G, by which the material under operation is removed' as it
becomes: roasted, and is then introduced into the centre or preparing chamber
B, which is also open at the top; and has a door H; by which the prepared

page_text: orc is removed, as required, into a small iron waggon I, or other suitable
receptacle, by which it is taken to the reducing furnace Figure 4, where the
separation of the scoria from the metal takes place. If the ore is put into
the chamber A without any carbonaceous matters, then these materials must
be added at the time it is removed from the chamber A (after roasting) to the
centre chamber B, where it is carbonized or prepared; but I prefer mixing
the ore and the carbonaceous matters together before roasting, and therefore
to proceed to operate in the following manner:-The raw ore, being crushed
small and mixed intimately with small coke or anthracite coal; and charged
into the compartment A, becomes sufficiently heated, so' as completely to
drive off the volatile matters by the time it arrives at the bottom; from
whence it is from time to time removed, and raised by some convenient
means to the mouth of the chamber B, into which, while in a heated state,
it is to be charged, along with any flux the quality of the ore may require.
The mixture descends gradually to the bottom of the furnace, and is abstracted
by the door H in a state, both physically and chemically, precisely similar to
that found in the common blast furnace at that part of such furnace where
the ore and flux are about to combine and 'fuse' together. This prepared ore
is then conveyed to the reducing furnace, Figure 4, which may be constructed
in many different ways, yet producing similar results. The product of the
preparing furnace, as required for the reducing furnace, should the following
properties (viz.), that the metallic part should contain as little carbon as
possible, and the earthy matter contained in the ore so associated with the
flux that they may melt and run off at as low a temperature as possible.
Fig. 4 is a vertical section of a reducing furnace, wherein the operation of
separating the scoria from the iron may be completed.
:
Fig. 5 is a sectional plan view of the same, the cover of the reducing
chamber being removed. This furnace is also composed of brickwork and
iron. K is the reducing chamber for receiving the previously prepared ore
and flux, and is composed of firebrick, and is heated by being in contact with
the fire, and also by the hot air arising from the combustion of fuel in the
fireplace L, which passes up the flues or hot-air chambers M to the chimney
at N. O, O, is the main brickwork surrounding the furnace; and forms' the
ashpit below; P is the movable cover of the reducing chamber; and Q,
the slaghole, by which the melted scoria is allowed to run off as it becomes
fused, leaving the metallic parts behind. "On a fresh charge of hot prepared
ore being placed in the chamber K, the open top is to be closed by the
cover P, and the fire kept up as before stated to the required degree of heat,
2
:

page_text: and when the scoria has all run off, the metal is to be removed in any
convenient manner, and further operated upon or used for any purposes before
named, when the reducing furnace will be ready for another charge.
Fig. 6 is a vertical section of another modification of a reducing furnace,
in which the same effects may be obtained. The outer casing of this furnace
is composed of iron, and the fireplace is of an annular form surrounding the
reducing chamber, and the combustion is produced and maintained by a
blast pipe R, leading into the ashpit S instead of a natural draft as in the
former furnace.
an
Fig. 7 is a horizontal section, taken in the line a, b, in Fig. 6; and as
the same letters of reference are marked upon corresponding parts as in the
former Figures, no further description will be necessary, as the construction
and mode of operation will be understood from the Drawing and former
description. Or. partly the same effect may be produced, although in a
imperfect manner, in the open furnace into which blast is introduced, as
shewn in the vertical and horizontal sections Figs. 8 and 9, where A is the
reducing chamber formed of brickwork, surrounded with an iron chamber B,
filled with water to prevent radiation of heat or destruction of the brickwork.
C, C, are the tuyere pipes leading from the blowing apparatus. The pre-
pared ore with the fuel is placed in the chamber, and the blast turned on,
which is to be regulated according to the degree of heat required to cause the
scoria to melt, when it will run off at the "slaghole" D, leaving the metal
in the chamber, the fuel being consumed, and mostly passed off in vapour; or
the same effect might be obtained by a modification of the common- blast
furnace, by attaching a reducing chamber of this description at that part of
the furnace where the ore or scoria are about to melt and descend into the
usual melting chamber; but I prefer operating with separate preparing. and
reducing furnaces, as above shewn and described, as the process of separating
the scoria from the metal is conducted much more perfectly and economically.
If the metal be required for the purpose of making bar iron by puddling,
or if it is, to be used in a refinery, it may be taken in the state in which it
comes from the reducing furnace. If wanted for casting, it may be melted
from this state, but if required for sale as raw material it would be best
remelted and run into "pigs" or masses; and any kind of furnace will do for
this purpose, such as are commonly used for melting pig iron at foundries.
The economy of my improved process is effected by saving the cost of erecting
large blast furnaces, steam engines, and blowing apparatus, similar to those
which are at present used for iron smelting in Staffordshire, South Wales, &c.

page_text: And also I derive an additional advantage by my method of operation, as I
produce a uniform quality of metal during the whole time the furnace may.
be working, the produce being daily the same, and the quantity produced in
proportion to the size of the furnace used.
Having now described and ascertained my Invention; and the manner of
carrying the same into effect; I wish it to be understood that I am aware
that iron ores have been submitted to the chemical process of cementation;
and also that the metal, together with the earthy parts or flux or scoria, have
been by incans of heat reduced together in a common melting pot or crucible
into a sort of pasty mass or consistency, and a portion of the metal separated
therefrom by puddling or stirring with an iron rod; but this has only been
done in a very expensive and wasteful manner, and merely as a chemical
experiment, or to obtain testing samples of the ore; and the portion of the
metal so separated from the pasty mass has consequently been mixed up
more or less with scoria, whereas by my improved process the scoria and
flux are so operated upon as to cause them to fuse and flow off and separate
from the metallic parts without any stirring, puddling, or other mechanical
operation. And, therefore, I claim as my Invention, secured to me by the
above in part recited Letters Patent, the improved mode or manner or process
of operating upon the earthy or other foreign matters contained in the iron
ore, so as to cause them to fuse or melt and separate from the metallic parts
and run off, leaving the metal behind in the furnace or reducing chamber, as
herein-before set forth and explained.
In witness whereof, I, the said Charles Sanderson, have hereunto set my
hand and seal, this First day of April, in the year of our Lord One
thousand eight hundred and thirty-nine.
CHARLES (L.s.) SANDERSON.
CHARLES (L.S.) SANDERSON.
Signed, sealed, and delivered (being
first duly stamped), by the within-
named Charles Sanderson, in the
presence of

page_text: AND BE IT REMEMBERED, that on the First day of April, in the
second year. of the reign of Her Majesty Queen Victoria, the said Charles
Sanderson came before our said, Lady, the Queen in Her Chancery,, and
acknowledged the Instrument aforesaid, and all, and every thing therein. con-
tained and specified, in form above written. And also the Instrument afore-
said was stamped according to the tenor of the Statute made in, the fifty-fifth.
year of the reign of His late Majesty King George the Third.