IMPROVEMENTS IN THE METHOD OF AND APPARATUS FOR DRYING CHINA CLAY AND SIMILAR MATERIALS
Year: 1884

page_text: We JOHN LOVERING, China Clay Merchant and JAMES BELL, Draper, both of
St Austell in the County of Cornwall do hereby declare the nature of our
invention for IMPROVEMENTS IN THE METHOD OF AND APPARATUS FOR DRYING
CHINA CLAY AND SIMILAR MATERIALS, to be as follows:-
This invention consists of a novel method of drying China clay after the
impurities have been washed out of it, and of improvements in the means for
carrying out the drying operation.
The usual plan of drying China clay is to expose the open pans or "Drys" in
which the clay is placed, to the direct action of fire, a course which risks the
burning of the clay unless great care and attention are given to the drying
operation. The pans also require constant repairs, as they rapidly burn out, thereby
causing continual expense, delay, and labour.
The drying operation is also retarded by the condensation of the vapour on the
surface of the clay, caused by the vapour coming into contact with the cold air.
In carrying out our Invention, we construct a chamber of any desired length,
width and depth, and perfectly air tight except at its top which top forms the
drying pan.
This drying pan is composed of porous tiles or specially formed bricks which are
laid upon iron bars placed transversely over the air chamber.
The tiles which will be from 12 to 24 inches in length and varying in breadth as
may be desirable and about four inches thick, will be laid on the bars, and cemented
or otherwise secured together.
The bricks if used we form about 1 foot long, 24 inches wide and 6 inches deep.
The two sides of these bricks are vertical for about 2 inches down, and are then
bevelled off so that when two bricks are placed side by side there shall be a wedge
shaped space between them open to the air chamber. The bricks are placed end to
end on the bars, the ends being cemented or otherwise secured together, but the
sides must be made to fit together accurately, no cement or other material being
placed between them.
Into the air chamber thus formed, heated air is forced by any convenient means,
which heated air will find its way through the porous tiles or the crevices between
the bricks, and through the wet clay placed on the pan to be dried, thereby driving
off the moisture, and effectually and speedily drying the clay,

page_text: If desired cold air may be forced into the chamber and there heated. For this
purpose and for the purpose of preserving the heat of the heated air in the chamber,
or if necessary of increasing such heat, we arrange longitudinally of the chamber
a plate iron tube at one end of which is placed a fire place to heat the tube, the
other end of the tube being in connection with a chimney.
As additional means for heating the cold air we may pass some portion of it
before it passes to the chamber through pipes arranged in the tube and fire place.
As a means for preventing the condensation of the vapour rising from the wet
clay, we place over the drying pan movable covers of any convenient construction
and made of some non conducting material....
Means will be provided for allowing the vapour to pass off.
By the use of the apparatus above described, the clay will be dried much quicker
than heretofore, and more effectually, without any risk of burning.
Although we have referred more particularly to china clay, it will be evident
that other materials may also be dried by the method and means above described.
Dated this 10th day of Anril 1884

page_text: We JOHN LOVERING China Clay Merchant and JAMES BELL Draper, both of
St Austell in the County of Cornwall do hereby declare the nature of our
invention for IMPROVEMENTS IN THE METHOD OF AND APPARATUS FOR DRYING
CHINA CLAY AND SIMILAR MATERIALS and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
This Invention consists of a novel method of drying China Clay after the
impurities have been washed out of it, and of improvements in the means for
carrying out the drying operation.
The usual plan of drying china clay is to expose the open pans or "Drys" in
which the clay is placed to the direct action of fire, a course which risks the
burning of the clay unless great care and attention are given to the drying
operation The pans also require constant repairs as they rapidly burn out, thereby
causing continual expense, delay and labour.
The drying operation is also retarded by the condensation of the vapour on the
surface of the clay caused by the vapour coming into contact with the cold air.
In carrying out our Invention we employ hot air as the drying medium which is
forced up through the china clay thereby driving off the moisture.
In the accompanying Drawing Fig: 1 is a longitudinal section of the apparatus
which we employ in carrying out our Invention, Fig: 2 is a sectional plan view of
the same, Fig: 3 is a transverse section, and Figures 4 shew the form of the bricks
used in connection with our said Invention.
A is an air chamber of any desired length width and depth and perfectly
air-tight except at its top which forms the drying pan or "Dry" B-In the
chamber A, and longitudinally thereof are two walls A formed with arches which
serve as supports to the bottom of the "dry" B.-The sides of this drying pan we
prefer to form of brick, backed with concrete, but the bottom a. is composed either
of porous or finely perforated tiles, or specially formed bricks C, which are laid
upon iron bars b. placed transversely across the air chamber A, and supported at
two points in their length by the walls A¹.
The finely perforated or porous tiles are from 12 to 24 inches in length varying
in breadth as may be desirable and about four inches thick-These tiles when laid
on the bars b. are cemented or otherwise secured together.
When bricks are used we prefer to form them about 1 foot long, 21, inches wide,
and 6 inches deep-The two sides of these bricks are vertical for about 2 inches
down, and are then bevelled off so that when two bricks are placed side by side
there shall be a wedge shaped space between them open to the air chamber, as
shewn in the cross section Fig: 4-The bricks are placed end to end on the bars,
the ends only being cemented or otherwise secured together but the sides being
made smoth so as to fit together closely. No cement or other adhesive material is
used for the sides.
Into the air chamber A thus formed heated air is forced by any convenient
means which heated air will find its way through the porous or perforated tiles, or
through the crevices between the bricks, and through the wet clay placed in the
"dry," thereby driving off the moisture and effectually and speedily drying the
clay.
.
For the purpose of heating the air in the chamber A, and for the purpose of
keeping up the heat therein, or if necessary of increasing such heat, we arrange

page_text: longitudinally of the chamber a plate iron tube or flue D, at one end of which is
placed a fire place E, to heat the tube, the other end of the tube being in connection
with a chimney F.-This flue is bolted or otherwise secured to iron plates fixed in
the masonry at opposite ends of the chamber, and is supported at various points in
its length in any convenient manner.
To allow for expansion and contraction of this tube we telescope it at the chimney
end thereof, as seen at D!.
The air is introduced by the pipe G with which are connected small perforated
tubes d. The tubes are arranged alongside of the flue D, and are perforated only
on the side nearest the flue so that the air as it issues in fine streams impinges
upon the hot flue, and thereby becomes readily heated.
In order to prevent the condensation of the vapour rising from the wet clay
and caused by the vapour coming into contact with the cold atmosphere we place
over the drying pan, movable covers of any convenient construction and made of
some nonconducting material.
Means are provided for carrying off the vapour which collects under the covers.
By the use of the apparatus above described the clay will be dried much quicker
more economically and more effectually than heretofore and without burning; and
the extensive repairs usually required in this class of apparatus will be almost
entirely obviated.
Although we have referred more particularly to china clay it will be evident
that other materials may also be dried by the method and means above described.
Having now particularly described and ascertained the nature of our said
Invention and in what manner the same is to be performed, We declare that what
we claim is
1st The mode herein described for drving china clay and similar materials, such