MACHINERY FOR DRYING WASHED COAL
Year: 1885

page_text: "
I, SAMUEL BUTLER of N° 127 Bute Road, Cardiff, in the County of Glamorgan,
Engineer, do hereby declare the nature of the said Invention for "MACHINERY
FOR DRYING WASHED COAL," to be as follows:-
This Invention relates to machinery for drying coal after it has been subjected
to a process of washing.
The washing of coal is effected by various means for the extraction of stone and
other impurities. The coal however, after washing is wet, which is not a serious
disadvantage for coke-making, but for some purposes such as fuel-making, or for
shipment, it is necessary to have the coal dry.
The difficulty of drying coal has prevented the adoption of washing machines in
connection with Patent Fuel Works except on a very small scale. To dry coal
from a washing machine, which is necessarily very wet, and to avoid loss of time,
I use the heated gases from a furnace which I bring in direct contact with the coal
itself. Apparatus has been used for drying coal from a washing machine but in
consequence of the loss of heat and consequent high cost of drying, it has not come
into extensive use. The drying machinery hitherto used consists in moving the
wet coal over an iron plate kept hot by a flue beneath. It will be seen that in this
case the heat has to pass through the iron before it can be taken up by the wet
coal. Coal is a bad conductor of heat and refuses to communicate the heat of the
iron plates to the water by which it is saturated and which is required to be
evaporated.
The object of this Invention is to bring the heated gas into direct contact with
the wet coal without the medium of the iron plates, effecting a great saving of heat
and enabling a much larger quantity to be dried.
In order that my Invention may be more fully understood, I hereto annex a sheet
of drawings illustrative thereof.
Figure 1 is a washing machine and drying machine combined. The washing
machine may be constructed as shewn in section at A, or it may be of any other
kind or form. The wet coal is represented coming away from the washing machine
at B, whence it is conveyed by an endless band conveyor C, which is constructed
with perforated sheet iron bottom to allow as much water as will drain from the
coal to run down the inclined trough D. This trough has its lowest point
terminating in a wall at E, the endless chain of bucketa F being used for
returning the water back to the tank of the washing machine.

page_text: The endless band conveyor C, is constructed of considerable length and is geared
to the drying machine by worm gearing at G and H so as to travel very slowly.
The wet coal after draining is discharged over the end of the conveyor at I where
it is picked up by an endlass chain of buckets and is delivered into the drying
machine at J.
The drying machine is a cylinder formed in segments, preferably of cast iron and
having a number of floors K, K, K, K. There is a shaft running through its
centre having keyed upon its clearing arms or knives working close on the surface
of each floor. There is a hole in each floor through which the coal may fall from
one floor to the other.
1.33
These holes are so arranged in each floor that the coal can only fall the depth of
one floor for one revolution of the shaft and so the coal is made to pass downwards
from floor to floor becoming dryer and dryer until it finds its exit through the
bottom at L. The heated gases pass into the cylinders at M and finding their way
up through the same holes by which the coal is coming down, obtain their exit
at N carrying with them to the stack the steam which has been evaporated from
the coal.
Instead of the drying machine being vertical it may be horizontal as shewn in
Figures 2, 3, and 4.
"
In this case the cylinder is still constructed of cast iron in segments, but without
any floors, and is closed at both ends. There is a shaft through the centre having
upon it a number of clearing arms with their blades at an angle in the form of a
screw propeller. The coal after draining is passed into the cylinder at A and is
tossed about and propelled forward by the screw cleaner arms at each revolution of
the shaft and becomes dryer and dryer until it is discharged through a hole in the
end or bottom at B.
The heated gases from an adjacent furnace C enter the cylinder at D and pass
out at E taking with them the moisture in the form of steam to the stack. There
may be two or more of these drying cylinders and the coal may be made to pass
from one to the other in which case heat will be economised.
-
It is desirable to have a very large Blue for conducting these waste gases to the
stack, with cross walls built therein for catching any dust which may come away
from the coal. There should be openings to this flue by which it may be cleared
without difficulty as otherwise the dust is liable to take fire.
Dated this 18th day of June 1885.

page_text: I, SAMUEL BUTLER, of 127 Bute Road, Cardiff, in the County of Glamorgan,
Engineer, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
This invention relates to machinery for drying coal after it has been subjected
to a process of washing.
The washing of coal is effected by various means for the extraction of stone and
other impurities.
The coal however after washing is wet which is not a serious disadvantage for
coke-making; but for some other purposes however, such as fuel-making or for
shipment, it is necessary to have the coal dry.
The difficulty of drying coal has prevented the adoption of washing machines in
connection with Patent Fuel Works, except on a very small scale.
To dry coal from a washing machine, which is necessarily very wet and to avoid
loss of time, I use the heated gases from a furnace which I bring in direct contact
with the coal itself. Apparatus has been used for drying coal from a washing
machine but in. consequence of the loss of heat and consequent high cost of drying,
it has not come into extensive use. The drying machinery hitherto used consists.
in moving the wet coal over an iron plate kept hot by a flue beneath. It will be
seen that in this case the heat has to pass through the iron before it can be taken
up by the wet coal. Coal is a bad conductor of heat and refuses to communicate
the heat of the iron plates to the water, by which it is saturated and which is
required to be evaporated.
The object of this invention is to bring the heated gases into direct contact
with the wet coal without the medium of the iron plates, effecting a great saving
of heat and enabling a much larger quantity to be dried.
In order that my said invention may be fully understood I have hereto annexed
a sheet of drawings illustrative thereof.
Figure 1 is a washing machine and drying machine combined. The washing
machine may be constructed as shewn in section at A, or it may be of any other
kind or form.
The wet coal is represented coming away from the washing machine at B, whence
it is conveyed by an endless band conveyor C which is constructed with perforated
sheet iron bottom, to allow as much water, as will drain from the coal to run down
into the inclined trough D. This trough has its lowest point terminating in a
well at E, the endless chain of buckets F being used for returning the water back
to the tank of the washing machine.
The endless band conveyor C is constructed of considerable length and is geared
to the drying machine by worm gearing at G and H so as to travel very slowly.
The wet coal after draining is discharged over the end of the conveyor at I where
it is picked up by an endless chain of buckets and is delivered into the drying
machine at J.
+

page_text: The drying machine is a cylinder formed in segments preferably of cast iron, and
having a number of floors K K K K. There is a shaft running through its centre
having keyed upon it clearing arms or knives working close on the surface of each
floor. There is a hole in each floor through which the coal may fall from one floor
to the other. These holes are so arranged in each floor that the coal can only fall
the depth of one floor for one revolution of the shaft, and so the coal is made to
pass downwards from floor to floor, becoming. dryer and dryer until it finds its
exit through the bottom at L. The heated gases pass into the cylinder at M and
finding their way up through the same holes by which the coal is coming down,
obtain their exit at N carrying with them to the stack the steam which has been
evaporated from the coal.
Instead of the drying machine being vertical it may be horizontal as shown in
Figures 2. 3 & 4. In this case the cylinder is still constructed of cast iron in
segments but without any floors and is closed at both ends. There is a shaft
through the centre having upon it a number of clearing arms with their- blades at
an angle in the form of a screw propeller. The coal after draining is passed into
the cylinder at A and is tossed about and propelled forward by the screw cleaner
arms at each revolution of the shaft and becomes 'dryer and dryer until it is
discharged through a hole in the end or bottom at B. The heated gases from an
adjacent furnace Center the cylinder at D and pass out at E taking with them
the moisture in the form of steam to the stack.
There may be two or more of these drying cylinders and the coal may be made
to pass from one to the other in which case heat will be economised.
It is desirable to have a very large flue for conducting these waste gases to the
stack, with cross walls built therein for catching any dust which may come away
from the coal. There should be openings to this flue by which it may be cleared
without difficulty as otherwise the dust is liable to take fire.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is :-
First. The use of a drying machine as herein set forth and described, working
in connection with a washing machine.
Second. The arrangement of a drying machine whereby heated gases are brought
into direct contact with wet coal from a washing machine,
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