Improvements in Apparatus for Drying Tea, Grain, and similar
Year: 1887

page_text: Date of Application, 19th Jan., 1887
Complete Left, 19th Nov., 1887
Complete Accepted, 13th Jan., 1888
[Communicated from abroad by PETER SMITH SWAN, of Calcutta, in the Empire of
India, Juto Manufacturer.]
Improvements in Apparatus for Drying Tea, Grain, and similar
I, SAINT JOHN VINCENT DAY of 115 St. Vincent Street, Glasgow, in the County
of Lanark, North Britain, Engineer and Patent Agent do hereby declare the nature
of this invention to be as follows:-
This Invention, which relates to improvements in apparatus for drying tea, grain
and similar produce, has for its object to effect economy in the fuel employed in such
apparatus by utilizing the waste heat from the furnace of the steam boiler used for
driving the blowing fan by which air is driven through the air heater and dryer.
The present improvements consist in connecting the smoke box of the engine by
a flue or flues leading into the chamber containing the air heating pipes or passages
whereby the escape of a large portion of heat up the chimney of the boiler is prevented
whilst such beat itself is imparted to the air which dries the tea, grain or other
produce as it passes through the dryer. The heated air after it returns from the drver
is wholly or partly discharged into the fire place wherein the fuel for generating
the heat for heating the air is burned. The pipe for conveying the exhaust steam from
the engine is provided with a cock and two discharge orifices so that the exhaust steam
can be discharged into the chimney of the boiler or into the short chimney of the air
heater or partly into both chimneys.
ST. JOHN V. DAY,
Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus for Drying Tea, Grain, and similar
Produce.
I, SAINT JOHN VINCENT DAY of 115 St. Vincent Street, Glasgow, in the County
of Lanark, North Britain, Civil Engineer and Patent Agent do hereby declare the
nature of this invention and in what manner the same is to bo performed, to bo
particularly described and ascertained in and by the following statement :—
This Invention which relates to improvements in apparatus for drying tea grain and
similar produce has for its object to effect economy in the fuel employed in such
apparatus by utilizing the waste heat from the furnace of the steam boiler used for
driving the blowing fan by which air is driven through the air heater and dryer.
The present improvements consist in connecting the smoke box of the engine by
a fluc or flues leading into the chamber containing the air heating pipes or passages
whereby the escape of a large portion of heat up the chimney of the boiler is
prevented whilst such heat itself is imparted to the air which dries the tea, grain or
other produce as it passes through the dryer. The heated air after it returns from the
dryer is wholly or partly discharged into the fire place wherein the fuel for generating
the heat for heating the air is burned.
The pipe for conveying the exhaust steam from the engine is provided with a cock
and two discharge orifices so that the exhaust steam can be discharged into the
chimney of the boiler or into the short chimney of the air heater or partly into both
chimneys.
In order that this Invention may be properly understood and readily carried into
effect, will now proceed to describe the drawings hereunto annexed.
On sheet 1, of the annexed drawings, I have shewn an air heater suitable for the
purposes of this Invention.
Figure 1, is a transverse vertical section of the said heater.
Figure 2, is a horizontal section thereof, on the line a, b, Figure 1.
As the heater shewn by these Figures is substantially of the same kind as that fully
described in and shewn on the drawings annexed to my previous specification No. 833
dated 19th January 1887, it is not necessary herein to repeat a description thereof
and more especially as there is no new or substantially different feature in the heater
shewn in the drawings hereunto annexed. The only difference which it is necessary
to mention is that the cold air enters the heater at the upper part in place of at the
lower and traverses to the bottom of the heater being driven through it by means of the
fan or blower D, the discharge pipe of which is marked G, in Figures 3 and 4, and
as will be seen from Figure 3, rises up to the top of the heater A. From the situation
of the fire-grate H', being at a lower level than that shewn in Figures 1, and 2, of
the drawings annexed to my former specification No. 833 A.D. 1887, it follows that
the heater and products of combustion arising therefrom in place of gradually
descending through the heater in passing through the pipes thereof ascend through it
whereby as the air and heated products of combustion move in opposite directions the

page_text: air receives gradual accession of heat relatively with the gradual diminution of the
temperature of the products of combustion.
Figure 3, is an elevation and Figure 4, a plan partly in horizontal section of the
combination of apparatus constituting the present Invention and consisting of the
heater A, the boiler B, engine C, blower D, and tea-dryer E. The shafting and pulleys
between the engine C, and blower D, are omitted in the said drawings as it will be
easily understood that the blower or fan D, is driven by means of a belt passing over
its pulley F, and actuated from the engine C, in the ordinary manner of belt
driving.
The hot air on leaving the heater A, is discharged from the bottom thereof into the
upright tube H, whence it passes into the dryer E, through the pipe I, and after
passing through the dryer it escapes therefrom by the horizontal pipe J, leading to the
vertical pipe L, and thence by the inclined pipe M, into the pipe N, leading to the
hollow furnace-door O, and by a combination of the said pipe N, to the fire grate of
the boiler B, another pipe P, is provided leading from the upright pipe H, to the
pipe N, for the purpose of supplying hot air direct from the heater A, to the fire
grate H, when required. Both the pipes M, and P, are provided with valves or
Hampers not shewn in the drawings by means of which the supply or return of hot
air may be regulated or directed from the furnaces altogether into what is known as a
"witherer" being a well-known apparatus for withering tea-leaf preparatory to the
final drying thereof in the dryer E.
Any of the well-known forms of tea-dryers for drying tea by heated air may be
used and I have merely indicated by means of that part of the apparatus marked E,
the external casing of such tea-dryer. The tea to be dried is fed into the dryer by
means of the hopper Q, and gradually travels to the hottest part of the dryer from
whence it is removed.
After steam is generated in the boiler B, a damper in the chimney R, thereof is
closed and the hot gases from the boiler B, are discharged from the smoke-box thereof
into the air heater through the pipe X. The pipe X is also provided with a damper
not shewn in the drawings for closing communication between the boiler and air
heater when required. The exhaust pipe S, of the engine is provided with a valve S',
by means of which the exhaust steam may be discharged either into the chimney R,
or into the chimney T, of the air heater or partly into both as required.
Having now particularly described and ascertained the nature of the said Invention
and in what manner the same is to be performed I declare that what I claim is :-
The combination of an air heater, boiler, engine and fan with a dryer for drying
tea, grain and similar produce and provided with dampers for opening or closing
communication between the air heater and smoke-box of the boiler and otherwise so
arranged as to return the whole or portion of the heated air passing out of the drying
apparatus for use as hot air for supplying the heater and boiler furnaces or either of
them substantially as hereinbefore described and shewn upon the annexed sheets of
drawings.