IMPROVE MENTS IN THE SYSTEM OR MODE OF CALCINING AND EXTRACTING. THE OILS AND GASES FROM IRONSTONE AND OTHER MATERIALS, AND IN THE APPARATUS OR MEANS EMPLOYED THEREFOR
Year: 1864

page_text: LETTERS PATENT to Henry Aitken, of Falkirk, in the County of Stirling,
North Britain Iron Works, Manager, for the Invention of "IMPROVE
MENTS IN THE SYSTEM OR MODE OF CALCINING AND EXTRACTING. THE OILS AND
GASES FROM IRONSTONE AND OTHER MATERIALS, AND IN THE APPARATUS
OR MEANS EMPLOYED THEREFOR."
Sealed the 20th October 1864, and dated the 9th May 1864.
PROVISIONAL SPECIFICATION left by the said Henry Aitken at the
Office of the Commissioners of Patents, with his Petition, on the
9th May 1864.
I, HENRY AITKEN, of Falkirk, in the County of Stirling, North Britain Iron
Works, Manager, do hereby declare the nature of the said Invention of
"IMPROVEMENTS IN THE SYSTEM OR MODE OF CALCINING AND EXTRACTING THE OILS
AND GASES FROM IRONSTONE AND OTHER MATERIALS, AND IN THE APPARATUS OR
MEANS EMPLOYED THEREFOR," to be as follows, that is to say :-
This Invention relates to a certain improved system or mode to be used for
the calcination of ironstone and extraction of gases and oils from the same
and other substances, and consists in the application of a large inclined flue
or duct through which the substance to be calcined passes, the said flue or duct
either being with or without a furnace or furnaces or external flues or fires.
The heat is supplied either by the ingredients in the substance itself, or by
means of fuel intermingled with the substance to be calcined; or the flue may

page_text: be heated by external means as before mentioned. After the substance is put
in at the top of the inclined flue or duct, and is sufficiently calcined, a workman
is stationed at the lower mouth of the flue who takes out the substance and
places it in wagons, barrows, or on a screen for the purpose of being cleaned,
taken away, or cooled. The advantages resulting from this system of complete
calcining are, firstly, the capability of calcining ironstone all the year round
without damage to crops; secondly, the obtaining the ironstone properly
calcined and in a thoroughly open and desiccated state before being intro-
duced into the blast furnace, thereby effecting a saving in the cost of transit in
consequence of no water being absorbed, and in other charges, as well as a con-
siderable saving in the blast furnace, from the fact of the ironstone being com-
pletely calcined, and the heat of the furnace having no water to expel, thereby
effecting a saving of fuel, and a more economic working of the furnace; third,
the calcining will be more effectually and regularly performed, and the labour
in filling will be much diminished; fourthly, the sulphur in the substance, if
such exists, will be carried off and not allowed as at present to mix with the
ironstone. Before calcination the gases being driven off either by the heat
generated in the calcining, or from the heat of the outside fires, are carried to
suitable vessels, where they are condensed and rendered fit for use; or, if suit-
able, the gas may be pumped into chambers and rendered available as gas, or
whatever gases may be considered worthless may be carried off by a chimney.
The heat in the inclined flue or duct is regulated by ports with moveable
covers in or connected with flues leading either to the chambers before
referred to or to the chimney.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Aitken in the Great Seal Patent Office on the
9th November 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
AITKEN, of Falkirk, in the County of Stirling, North Britain Iron Works,
Manager, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of May, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant
unto me, the said Henry Aitken, Her special license that I, the said
Henry Aitken, my executors, administrators, and assigns, or such others

page_text: as I, the said Henry Aitken, my exécutors, administrators, or assigns,
should at any time agree with, and no others, from time to time and at
all times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN THE SYSTEM OR MODE OF CALCINING AND EXTRACTING THE
OILS AND GASES PROM IRONSTONE AND OTHER MATERIALS, AND IN THE APPARATUS
OR MEANS EMPLOYED THEREFOR," upon the condition (amongst others) that
I, the said Henry Aitken, my executor's or administrators, by an instrument in
writing under my hand and seal, or under the hand and seal of one of
them, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar,
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Henry Aitken, do hereby declare
the nature of my said Invention, and in what manner the same is to be.
performed, to be particularly described and ascertained in and by the following
statement, reference being had to the accompanying Drawings, and to the
letters and figures marked thereon, that is to say:
My said Invention relates to a certain improved system or mode to be used
for the calcining of ironstone, and extraction of gases and oils from the same
and other substances, and consists in the application of a large inclined flue or
duct through which the substance to be calcined passes. The said flue or
duct either being with or without a furnace or furnaces, or external fire or
fires. The heat is supplied either by the ingredients in the substance itself,
or by means of fuel intermingled with the substance to be calcined, or the
flue may be heated by external means as before mentioned. After the sub-
stance is put in at the top of the inclined flue or duct, and is sufficiently
calcined, a workman is stationed at the lower inouth of the flue, who takes out
the substance and places it in wagons, barrows, or on a screen for the purpose
of being cleaned, taken away, or cooled. The advantages resulting from this
system of complete calcining are, firstly, the capability of calcining ironstone"
all the year round without damage to crops; secondly, the obtaining the
ironstone properly calcined, and in a thoroughly desiccated and open state
before being introduced into the blast furnace, thereby effecting a saving in the
cost of transit in consequence of no water being absorbed, and in other
charges, as well as a considerable saving in the blast furnace from the fact of
the ironstone being completely calcined, and the heat of the furnace, having
no water to expel, thereby effecting a saving of fuel and a more economic

page_text: working of the furnace; thirdly, the calcining will be more effectually and
regularly performed, and the labour in filling will be much diminished
fourthly, the sulphur in the substance, if such exists, will be carried off and not
allowed as at present to mix with the ironstone. Before calcination the gases
being driven off either by the heat generated in the calcining or from the
heat of the outside fires are carried to suitable vessels where they are con-
densed and rendered fit for use, or if suitatable the gases may be pumped into
chambers and rendered available as gas, or whatever gases may be considered
worthless may be carried off by a chimney. The heat in the inclined flue or
duct is regulated by ports with moveable covers or valves in or connected
with flues leading either to the chambers before referred to, or to the
chimney.
And in order that my said Invention may be properly understood I shall
now proceed to describe the system, mode, or manner under which the same is
or may be used or practically carried into effect, reference being had to the
several Figures upon the two explanatory Sheets of Drawings which I have
hereunto appended for the purpose of more completely elucidating the same,
and in both of which similar parts are indicated by corresponding letters of
reference, that is to say:-
Figure 1, on Sheet 1, represents a longitudinal section of my improved
calcining kiln; Figure 2 is a transverse section of the same taken upon the
line 1, 2, Figure 1; and Figure 3, Sheet 2, is a general plan of the entire
apparatus.
In Figure 1, the body or main portion of the kiln itself, marked A, is by
preference made of fire-brick, but other suitable substances may also be used,
in the top or upper portion of which two openings B are formed, and these,
when the kiln is charged, are closed over by the doors B', and securely held
down by the cramp handles C, more particularly seen in the plan, Figure 3,
in order that the doors may be perfectly tight so as to prevent the escape of
the
gases which issue from the substances being calcined, they are luted with
clay or other plastic material. In the upper inclined face of the kiln A several
openings D are formed, with short upright necks D¹ made of fire-clay or other
fire-resisting material, and from the upper portions of these extend the pipes
or ducts E, which are carried over, and their further ends secured to the top
of another larger duct F, Figure 3, this duct F being in direct communication
with the chimney G. The pipes or ducts E are fitted with valves, not shown
in the Drawings, for the purpose of closing the communication of the kiln A
with the chimney G when such is required, the communication may however
be cut by placing a damper in the large, duct F, thus the connexion between

page_text: the kiln A and the chimney G may be wholly or partially discontinued, which
arrangement enables the amount of draft to be regulated according to the
nature and requirements of the substance under treatment. The body of the
furnace A is held firmly together by the upright iron posts H driven into the
ground on either side of it through the top: and lower portions of which the
tie bolts H' are passed and secured at their ends by nuts, as shown in Figures
1, 2, and 3. Beneath the lower portion of the kiln A a fire grate I is
situated as seen in Figure 1, this extends to and is in connexion with the kiln
proper by means of a series of perforations I¹. The use of this last-named
part being herein-after fully described and referred to. The lower part of the
kiln A is fitted with a door J, moveable on the hinges J', its use being to
enable the calcined material to be taken out of the kiln as soon as the
process is sufficiently carried out. Immediately outside the door J, and on a
slight incline there is placed the grating K having a large cavity or pit L,
beneath, more particularly seen in Figure 1, the use of the grating being to
allow the passage through it of any small or refuse portions of the substance
received from the kilns, so that it may not be transported together with the
larger and more perfect portions over the screen M to the truck N. In the
upper part of the lower inclined face of the kiln there are fixed a series of
small ducts O, their inner sides being protected by the shades P, so as to
prevent as much as possible the ingress of portions of the solid material, their
outer ends are situated within the large duct Q which is in direct communica-
tion with the condensor R situated as shown a short distance below the upper
part of the kiln.
Having now described in detail the several parts of my Invention I will
now proceed more particularly to explain the mode of operating with the
same, to be as follows, that is to say:-
:
When it is desired to calcine ironstone, (if such be of a sufficiently car-
bonaceous kind) there is first placed in the lower portion of the kiln A some
ignited fuel, after which the raw ironstone itself is poured inty the kiln
through the doors B', and when a sufficient quantity of it is placed therein
the doors are closed, and it consequently becomes heated to an extent which
can be regulated at will by the valves or dampers in the ducts D, or in the
manner berein-before described. When the temperature of the substance
has attained a sufficient height at which the carbonaceous gases are driven off*
if they are of a valuable nature, the valves in communication with the chimney
are entirely or partially closed, and the gases themselves are carried through
the small ducts, thence through the larger duct Q into the condenser R, which
being maintained at a much lower temperature than that of the kiln, the

page_text: gases when passed therein are speedily condensed. In some cases I insert
water into the kiln for promoting the condensation of the gases, and steam is
also used for the same purpose, either of these may be introduced when
required either into the condenser or kiln. When the ironstone to be cal-
cined is not impregnated with an amount of carbonaceous matter sufficient
to carry on its own combustion additional heat is imparted to it by means of
the separate fire on the grate, the heat from which passes into the kiln
through the perforations in the manner herein-before described. The kiln
herein-before described may also be advantageously and economically
employed for the purposes of converting into coke, coal, shale, and other
bituminous and combustible substances. The length, breadth, and degree of
inclination of the kiln vary with the properties and qualities of the substances
to be treated in any of the ways herein-before referred to. The chief advantages
resulting from this Invention are, firstly, the obtainment of the gases of iron-
stone and other substances treated as herein-before described in the condensed
form as oils, or uncondensed as gases, these having been hitherto lost in the
ordinary mode of calcination and certain systems of coking; secondly, the
reduction in weight of the ironstone prior to its being conveyed away to the
blast furnaces or to distant parts, this last-named change also effecting a
considerable saving in the cost of transit, not only in ironstone, but also in
other substances whether calcined or coked. Owing to the routine of the pro-
cesses berein-before referred to a great saving of labour is effected in the
calcination or coking of the before-mentioned substances as well as in filling
them into waggons for being conveyed away.
Having now described the nature of my said Invention, and the manner
in which the same is or may be used or practically carried into effect, I
would observe, in conclusion, that I do not confine myself to the precise
details herein before described, as many variations may be made there-
from without deviating from the true principles or main features of my
said Invention, but what I consider to be novel and original, and therefore
claim as the Invention secured to me by the herein-before in part recited
Letters Patent is,―
First, the general arrangement and construction of kilns for calcining iron-
stone and similar substances, or for coking bituminous substances, as well as
the obtainment of the valuable gases either as gases or oils if. thought
desirable.
Second, the conversion into coke of coal, shale, and other bituminous sub-
stances in the manner herein-before described, or any mere modification
thereof.

page_text: Third, the application and insertion of water into the kiln for assisting the
condensation of the gases, and for regulating the temperature of the kiln as
herein-before described.
Fourth, the application and insertion of steam into the kiln for the purpose
of assisting the condensation of the gases, also for regulating the temperature
of the kiln as herein-before described.
In witness whereof, I, the said Henry Aitken, have hereunto set my
hand and seal, this Fourth day of November, One thousand eight
hundred and sixty-four.
HENRY AITKEN. (L.S.)