IMPROVEMENTS IN FURNACES FOR CALCINING CARBONATE OF PROVISIONAL SPECIFICATION
Year: 1880

page_text: LETTERS PATENT to William Black, Ironfounder, of South Shields, and
Thomas Larkin, Manager of Chemical Works, of East Jarrow, for an
Invention of "IMPROVEMENTS IN FURNACES FOR CALCINING CARBONATE OF
PROVISIONAL SPECIFICATION left by the said William Black and Thomas
Larkin at the Office of the Commissioners of Patents on the 2nd November
1880.
WILLIAM BLACK, Ironfounder, of South Shields, and THOMAS LARKIN, Manager
of Chemical Works, of East Jarrow. "IMPROVEMENTS IN FURNACES FOR
CALCINING CARBONATE OF SODA, ALKALI, AND OTHER LIKE SUBSTANCES, AND IN
APPARATUS CONNECTED THEREWITH."
This Invention, which relates to improvements in furnaces for calcining carbonates
of soda, alkali, and other like substances, has for its objects to enable such substances
to be worked more evenly, rapidly, and effectively, and without the usual heavy.
deterioration to the machinery, and to enable the furnaces to produce proportionally
a greater quantity of finished material than heretoforc.
The Invention consists essentially in applying heat both to the top and bottom
surfaces of the substances to be calcined, in lieu of heating the top surfaces only,
as has been the practice hitherto.
The substances to be calcined are placed upon a suitable bed; the flues from the
fires for heating the bottom surfaces of the said substances are carried beneath the
bed by a series of flues, whereby heat is imparted to the same; the fires for
heating the top surfaces of the substances upon the bed are carried over the
said substances, whereby heat is imparted to the top surfaces of the same, the
furnaces or fires for heating the bottom being independant of those for heating
the top, so as to facilitate the application or concentration of heat to any particular
part.
The bed carrying the substances to be calcined may be composed of fire clay,
quarls, iron, or other suitable material.
A vertical shaft and revolving arms with paddles, may be provided for the
purpose of manipulating and discharging the material.
Pipes or openings are led from the outside to the bed, so as to admit any necessary
amount of atmospheric air to the substances being calcined, either to cool the
machinery, or to oxidise the lower compounds of the substances present, so as to
produce better results in the finished material.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Black and Thomas Larkin in the Great Seal Patent Office
on the 2nd May 1881.
WILLIAM BLACK, Ironfounder, of South Shields, and THOMAS LARKIN, Manager
of Chemical Works, of East Jarrow. "IMPROVEMENTS IN FURNACES FOR
CALCINING CARBONATE OF SODA, ALKALI, AND OTHER LIKE SUBSTANCES, AND IN
APPARATUS CONNECTED THEREWITH."
Our said Invention, which relates to improvements in furnaces for calcining
carbonates of soda, alkali, and other like substances, has for its objects to enable such
substances to be worked more evenly, rapidly, and effectively, and without the
usual heavy deterioration to the machinery, and to enable the furnaces to produce
proportionately a greater quantity of finished material than heretofore.
The Invention consists essentially in applying heat both to the top and bottom
surfaces of the substances to be calcined, in lieu of heating the top surfaces only,
as has been the practice hitherto.
The substances to be calcined are placed on a suitable bed; the products of
combustion from the fires for heating the bottom surfaces of the said substances
are carried by a series of flues beneath the bed, whereby heat is imparted to the
same; the fires for heating the top surfaces of the substances upon the bed are
carried over the said substances, whereby heat is imparted to the top surfaces of
the same.
The furnaces or fires for heating the bottom are independent of those
for heating the top, so as to facilitate the application or concentration of heat to or
in any particular part.
A vertical shaft and revolving arms with paddles are provided for the purpose of
manipulating and discharging tho material.
Pipes or openings are led from the outside to the bed so as to admit any
necessary amount of atmospheric air to the substances being calcined, either to cool
the machinery or to oxydise the lower compounds of the substances present so as
to produce. better results in the finished material.
And in order that cur said Invention may be fully understood we shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the annexed Sheet of Drawings, the same letters of reference
indicating corresponding parts in all the Figures.
Figure 1 of the accompanying Drawings represents longitudinal section of a
calcining furnace constructed according to our said Invention; Figure 2 is a
horizontal section of the same taken the upper half along the lines 1, 2, and the
lower half along the lino 3, 4, (Figure 1), the line indicating the division of the
sections in the plan being marked x, x; Figure 3 is a half transverse section taken
along the line 5, 6, Figure 1, the line indicating the division of the section in
Figure 3 being marked y, y.
The bed A, carrying the substances to be calcined, is situated centrally between
the arched roof B and the ground level at B¹ of the furnace, and heat is applied
both to the top and the bottom surfaces of the substances upon the said bed. The
fire grates C, from which heat is imparted to the bottom surfaces of the substances
upon the bed A, are arranged in a series at one end of the furnace, as shewn in the
lower half section, Figure 2. The series of flues c from the fires or furnaces of the
said grates are carried beneath the bed A and run up and down the length of
the furnace, the products of combustion being carried in the direction of the
arrows, Figure 2, and escaping at the lower portions of the flues at c¹, as shown

page_text: more particularly in Figures 2 and 3. Dampers c³, Figure 3, are provided for the
regulation of the fires. The fire grates D, for imparting heat to the top surfaces of
the substances upon the bed A, are arranged at the opposite end of the furnace,
and the fires are carried over the said substances, whereby heat is imparted to the
top surfaces of the same, the products of combustion passing over the bed A and
escaping through the apertures d, Figure 3, and down the flue d¹, and escaping
at d, Figures 2 and 3. The arrangements of the fire grates of the top fires is shown
more particularly in the upper half section of Figure 2.
It will be evident that the furnaces or fires for heating the bottom surfaces of
the substances upon the bed A are independent of those for heating the top surfaces
of the substances upon the bed, whereby the application or concentration of the
heat to or in any particular part is facilitated.
The manipulating and discharging of the substances upon the bed A, as shown
in Figure 1 and in the upper half section of Figure 2, is effected by means of the
blades, paddles, or pallets c, hinged or otherwise attached to the revolving arms e¹,
the said arms radiating from the vertical shaft E, which is rotated by suitable
gearing fixed upon the top of the furnace, but not shown in the Drawings, the
gearing being operated by any suitable motive power situate upon the top of the
furnace or arranged in proximity to the furnace, and communicating motion to
the gearing by belting or by other suitable means. The revolving arms e', Figure 2,
are shown arranged over the circular calcining bed A, upon which the substances
to be calcined are deposited.
Any suitable number of blades may be employed, and they may be fixed upon
the arms e in any position therein, for which purpose the series of holes e²,
Figure 1, are provided, in any one of which the shank of ono of the blades may be
fitted. The vertical shaft E passes through the top of the furnace, and works in
bearings therein. The base of the shaft E is supported and works within a
footsteps, Figure 1, fixed upon the bed A, the bearing being enclosed within a
circular shield or casing e'. One or more of the arms e¹ may be provided with
scrapers for clearing the substances upon the bed A from the periphery thereof.
The bed A may be composed of fire clay, gnarls, iron, or other suitable material,
and it may be made up of several portions jointed together as shown.
Air holes F, Figures 1 and 2 are formed at one end of the furnace leading from
the outside to the bed A. so as to admit any necessary amount of atmospheric air
to the substances being calcined, whereby the machinery is cooled and the lower
compounds of the substances present are oxydised so as to produce better results in
the finished material. Other holes and apertures of greater or less area may be
provided at other parts of the furnace to be opened and closed when necessary for
the regulation of the supply of air and for other purposes.
For the discharge of the finished material from the bed A a door or opening G
is provided at one side of the furnace, as shown in the upper half section, Figure 2.
The said opening consists of a grating capable of being open and closed by a
slide g. The furnace is thus rendered self discharging, the revolving blades feeding
the calcined material through the said opening when it is opened. A barrow or
other receptacle is run beneath the opening for the reception of the finished
material.
Having now described and particularly ascertained the nature of our said
Invention, and the manner in which the same is or may be used or carried into
effect, we would observe in conclusion that what we consider to be novel and original,
and therefore claim as the Invention secured to us by the hereinbefore in part
recited Letters Patent is,-
First. In furnaces for calcining carbonates of soda, alkali, and other like substances,
applying heat both to the top and bottom surfaces of the substances to be calcined
by means of flues or chambers arranged above and below the calcining bed,
substantially as hereinbefore described.

page_text: Second. The employment of revolving arms provided with paddles for manipu-
lating the material upon the calcining bed, and discharging it therefrom, substantially
as hereinbefore_described.
In witness whereof, I, the said Thomas Larkin, on behalf of William Black and
myself, have to this our Specification set my hand and seal, this Second
day of May, One thousand eight hundred and eighty-one.
THOMAS LARKIN. (L.S.)