Improvements in or relating to the Roasting of Coffee and the like.
Year: 1889

page_text: Date of Application, 6th Sept., 1889
Complete Specification Left, 6th June, 1890-Accepted, 9th Aug., 1890
PROVISIONAL SPECIFICATION.
Improvements in or relating to the Roasting of Coffee and the like.
A communication from AUGUSTE SANDRON, of Menin, in the Kingdom of Belgium,
Engineer.
I, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E., do hereby declare the nature of this invention to be as follows :-
The present invention relates to improvements in apparatus for roasting coffee, cocoa,
chicory and the like by the direct action of superheated steam, and this apparatus
comprises three parts:
1. An apparatus generating superheated steam at a temperature as constant as
possible.
2. A roasting apparatus in which the superheated steam acts directly on the material
to be roasted which is suitably stirred or agitated and
3. An apparatus into which passes and in which is condensed the steam which in
roasting the material is charged with the moisture the latter gives off and which must
constantly be replaced by fresh steam of the desired temperature. This apparatus is
moreover provided with a receiver in which the condensed steam and the aroma which
it has absorbed are collected.
To superheat the steam it passes not only through a tube exposed to the direct
action of a furnace but also through a spiral tube enclosed in the walls of the
furnace.
The steam then passes into the roasting chamber which is provided with three
different concentric walls and distributes the steam evenly and rectifies the inevitable
variations consequent on the action of the furnace.
The steam generator consists of two domes placed on the furnace formed by a cast
iron hollow cylinder in which runs the spiral tube which receives the steam generated
between the two domes by means of a tube connecting the said spiral tube with the
space between the domes. The other end of the spiral tube is connected with a tube
passing in several turns through the fire box of the furnace.
By these means a superheated steam of the necessary temperature is obtained.
In case the steam generated in any already existing generator
used a separate
superheater based on the above described principle may be employed in conjunction
with it.
The roasting chamber is formed of three walls, between the outer two of which
passes an envelope or volume of superheated steam coming from the generator
through a suitable tube provided with a valve or stop cock. The outer wall is provided
with discharge pipe for the steam condensed in the space between the outer and
middle walls. In the space between the middle and inner walls the superheated
steam is also introduced through a suitable tube provided with a valve or cock and
from here it passes into the interior of the chamber through suitable openings in the
inner wall.
After having absorbed the moisture of the material to be roasted the steam passes
as also that from the spaces between the walls through a suitable tube to a condenser
consisting of numerous tubes surrounded by water in which the steam and the little
aroma it has carried with it are condensed, and then flow into a suitable receptacle.
The water surrounding the condenser tubes passes into a tank or equivalent surrounding
the receptacle into which passes the condensed steam and is discharged thence through
an overflow pipe or otherwise.
In the interior of the roasting chamber a drum of wire fabric or perforated
sheet metal is mounted on a shaft passing through the walls of the chamber

page_text: through suitable stuffing boxes and provided at one end with a pulley to drive
the said shaft. This shaft is provided with inclined flat boards or vanes which
agitate the material which is thus not only roasted but also winnowed in such
a manner that subsequent winnowing or sifting of the roasted material is not
necessary.
The spaces between the walls are provided with safety valves a manometer and a
pyrometer.
The two ends of the drum which are also of wire fabric or perforated sheet metal
can be removed for the purpose of emptying or charging the drum.
The end of the chamber is fastened by means of bolts and can be removed to permit
access to the drum.
This method of roasting results in a considerable reduction in the waste in
comparison with the ordinary methods employed.
Dated this 6th day of September 1889.
W. P. THOMPSON & BOULT,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to the Roasting of Coffee and the like.
A communication from AUGUSTE SANDRON, of Menin, in the Kingdom of Belgium,
Engineer.
1, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E., 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:-
-
The present invention relates to improvements in apparatus for roasting coffee,
cocoa, chicory and the like by the direct action of superheated steam, and this
apparatus comprises three parts:
1. An apparatus generating superheated steam at a temperature as constant as
possible.
2. A roasting apparatus in which the superheated steam acts directly on the
material to be roasted which is suitably stirred or agitated, and
3. An apparatus into which passes and in which is condensed the steam which
in roasting the material is charged with the moisture the latter gives off, and which
must constantly be replaced by fresh steam of the desired temperature. This
apparatus is moreover provided with a receiver in which the condensed steam and the
aroma which it has absorbed are collected.
To superheat the steam it passes not only through a tube exposed to the direct
action of a furnace, but also through a spiral tube enclosed in the walls of the
furnace.
The steam then passes into the roasting chamber which is provided with three
different concentric walls and distributes the steam evenly and rectifies the inevitable
variations consequent on the action of the furnace.
The construction of my apparatus is illustrated in the accompanying drawings.
The steam generator consists of two domes or shells S S₁ placed on the furnace
formed by a cast iron hollow cylinder R in which runs the spiral tube Q which
receives the steam generated between the two domes by means of a tube Q' connecting
the said spiral tube with the space between the domes. The other end of the spiral
tube is connected with a tube Q2 passing in several turns through the fire box of the
furnace.
By these means a superheated steam of the necessary temperature is obtained.
In case the steam generated in any already existing generator is used a separate
superheater based on the above described principle may be employed in conjunction
with it.

page_text: The roasting chamber is formed of three walls, between the outer two of which
passes an envelope or volume of superheated steam coming from the generator
through a suitable tube Q provided with a valve or stop cock L. The outer wall
is provided with a discharge pipe for the steam condensed in the space between
the outer and middle walls. In the space between the middle and inner walls the
superheated steam is also introduced through a suitable tube Q5 provided with a valve
or cock L and from here it passes into the interior of the chamber through suitable
openings in the inner wall.
After having absorbed the moisture of the material to be roasted this steam as also
that from the spaces between the walls passes through a suitable tube N to a
condenser consisting of numerous tubes surrounded by water, in which the steam
and the little aroma it has carried with it are condensed and then flow into a
suitable receptacle V. The cooling water surrounding the condenser tubes passes
from a reservoir X through the pipe W into a jacket or equivalent surrounding
the receptacle V and is discharged thence through an overflow pipe or otherwise.
In the interior of the roasting chamber C a drum D of wire gauze or perforated
sheet metal is mounted on a shaft E passing through the walls of the chamber
through suitable stuffing boxes F F and provided at one end with a pulley G to
drive the said shaft. This shaft is provided with inclined flat boards or vanes K
which agitate the material which is thus not only roasted but also winnowed in
such a manner that a subsequent winnowing or sifting of the roasted material is not
necessary.
The steam jackets are provided with safety valves a pressure gauge and a
pyrometer.
The two ends of the drum which are also of wire fabric or perforated sheet metal
can be removed for the purpose of charging or emptying the drum.
Both wire gauze or perforated ends of the drum are secured in place by means
of flat headed screws which may be loosened by hand to permit access to the drum.
To facilitate the filling and emptying of the roasting chamber or drum I arrange
above the apparatus a rail or rod whereon slide a number of pulleys from which the
cover of the receiver and the drum may be pivotally suspended. The said cover may
be applied without the use of any material for closing the joint but simply secured by
means of bolts or the like.
To remove the drum these bolts are taken out and the cover and the drum are
caused to slide upon the shaft. When the latter has come out it is slightly inclined
and turned round once or twice to allow of the removal of the roasted material while
at the same time the dust falling through the meshes and collected in the receiver
is removed from the latter. The drum is then turned up again for the reception of a
fresh quantity of material and then placed in position for further operation the cover
also being secured in place.
This roasting process offers this important industrial advantage that it considerably
reduces the amount of waste material obtained by the ordinary process.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. For the purpose of carrying out in practice the above described method the
employment of an apparatus consisting of:
(a) A boiler with a circular fire place provided with thick cast iron walls in which
a superheating coil is embedded for the purpose of maintaining the temperature
of the steam at a uniform degree.
(b) A roasting chamber consisting of a cast iron vessel provided with a steam
jacket and also with a third wall through which it receives steam at a
uniform temperature which acts directly upon the material to be roasted
contained in a drum of wire gauze or perforated metal enclosed in the said
roasting chamber.

page_text: .
(c) A surface condensing apparatus provided with a receiver adapted to condense
the steam previously cooled by the mixture of the superheated steam with the
damp evaporations rising from the substance to be roasted; such apparatus
being also arranged to collect the aroma of the material under treatment which
is for this purpose dissolved in the condensation water the whole substantially
as described and illustrated in the accompanying drawings.
2. The method of roasting coffee and similar substances by the direct action of
superheated steam exerted upon the materials it is desired to roast contained in a
closed vessel for the purpose of diminishing waste.
Dated this 6th day of June 1890.
W. P. THOMPSON & BOULT,
Agents for the Applicant.