Improvements in Apparatus for Mixing, Stirring, and Conveying Various Substances, and for Drying and Exposing the same to the Chemical Action of Gases, Vapours, and the like.
Year: 1886

page_text: Improvements in Apparatus for Mixing, Stirring, and Conveying
Various Substances, and for Drying and Exposing the same to
the Chemical Action of Gases, Vapours, and the like.
1 Dr. CHARLES LANGER, Analytical Chemist, of 43, Burton Crescent, W.C. do
hereby declare the nature of this invention to be as follows:-
This invention relates to improved apparatus for mixing solid or pasty substances,
or for turning over, stirring, and at the same time removing or conveying the same;
and also for exposing these substances to the action of gases and vapours while they
are being so stirred, turned over, and removed for the purpose of drying the substances
or of producing chemical change in them. The apparatus consists of a trough which
may be open or covered as the circumstances of the case require: in which trough are
placed two or more Archimedean screws, one right hand screw alternating with à left
hand screw and so on. These screws are set side by side in such a way that the
winding of cach stands at an angle of 90° to the winding of the next one, so that the
blades of one screw run as near as possible in the grooves of the other and keep it
clean. Each screw is moved in an opposite direction to the adjoining one.
The bottom of the trough in which they run is so shaped to fit that the screws keep
the trough clea. When the substances to be treated in this apparatus are to be
subjected to the action of gases other than cold air, the trough is covered in so as to
provide a channel for the gases to pass over the substances in the trough, and is
provided with inlets and outlets for the material to be passed through, and with inlets
and outlets for the gas to be brought in contact with the material. The trough and
the screws can be made of any suitable material according to the purposes for which
the apparatus is to be employed.
When it is desired to expose solid substances to corrosive gases as, for instance, in
the manufacture of bleaching powder, the whole apparatus can be made of lead or of
iron covered with lead, or the trough may be lined with fire-brick blocks of convenient
shape, or with asphalte, and the screws may be made of hardwood or of ebonite
or other material not acted on by the substances which have to pass through the
apparatus.

page_text: In making the screws of ebonite it will be advisable to make them in several pieces
fixed upon an iron shaft.
Amongst the various purpose for which this apparatus will be found useful I will
mention the mixing of all sorts of dry and pasty substances which it is desired to have
of great uniformity, such as colours and dyes and similar materials; the drying of
substances generally, more particularly those that have to be dried at low temperatures
in a current of warm air, such as bicarbonate of soda, starch, and innumerable similar
substances; for all purposes where it is desired to bring a solid or pasty substance into
intimate contact with a gas or vapour, notably the manufacture of bleaching powder,
burning of dust pyrites and the like. One great advantage of this apparatus is that it
produces very little dust when treating very light substances.
Dated this 19th day of June 1886.

page_text: Improvements in Apparatus for Mixing, Stirring, and Conveying
Various Substances, and for Drying and Exposing the same to
the Chemical Action of Gases, Vapours, and the like.
I CHARLES LANGER of 20, Avenue Road Regents Park, London in the County of
Middlesex, Chemist, 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 improved apparatus for mixing solid or pasty substances, or
for turning over, stirring, and at the same time removing or conveying tho same; and
also for exposing these substances to the action of gases and vapours while they are
being so stirred, turned over and removed, for the purpose of drying the substances,
or of producing chemical change in them.
The invention is best described by aid of the accompanying drawings, in
which,
Figure 1 shows a vertical section of apparatus,
Figure 2 a plan of conveyor, and
Figure 3 transverse section of same.
'
In these A is a trough which may be open or covered as the circumstances of the
case require; in this trough are placed two or more archimedean screws B B¹ B², B³
one right hand screw alternating with a left hand screw and so on. These screws are
set side by side in such a way that the winding of each, stands at an angle of
90 degrees to the winding of the next one, so that the blades of one screw run as near
as possible in the grooves of the other and keep it clean. In the drawing the worms
are shown with four complete threads each. Instead of complete threads however,
they can if desirable be broken threads-a series of vanes or paddles taking the place
of the complete threads, so that in the case of plastic materials liable to form lumps or
"ropes," a cutting action can take place, as a rule however, the complete worms are to be
preferred. Each screw is moved in an opposite direction to the adjoining one (in the
apparatus shown by pinions, C, C1, C2, C, and driving fast and loose pulleys D). The
bottom of the trough A in which they run is so shaped to fit the screws as shown, so
that the latter keep the trough clear. When the substances to be treated in this
apparatus are to be subjected to the action of gases other than cold air, the trough is
covered in so as to provide a channel for the gases to pass over the substances in the
trough, and is provided with inlets E and outlets, F for the material to be passed
through, and with inlets G and outlets H. for the gas to be brought in contact with the
material. Both inlet and outlet can be regulated by hopper and feed rolls or other
feeding mechanism, so that only a given amount of material shall enter or be discharged
in a given time.
In the drawing the feed mechanism is not shown, but the exit of the materials is
controlled by slide I so that it can be drawn off or stopped, as required, into
barrels or other receptacles as required the discharge being temporarily stopped, while
a full receptacle is being changed for an empty one. The trough and the screws can
be made of any suitable material according to the purposes for which the apparatus is
to be employed.

page_text: When it is desired to expose solid substances to corrosive gases, as for instance in
the manufacture of bleaching powder, the whole apparatus can be made of lead, or of
iron covered with lead, or the trough may be lined with fire brick blocks of convenient
shape or with asphalte, and the screws may be made of hard wood or of ebonite
or other material not acted on by the substances which have to pass through the
apparatus.
In making the screws of ebonite it will be advisable to make them in several pieces
fixed upon an iron shaft.
Amongst the various purposes for which this apparatus will be found useful, I will
mention the mixing of dry or pasty substances, which it is desired to have of great
uniformity, such as colours, and dyes, and similar materials, the drying of substances
generally, more particularly those that have to be dried at low temperatures in a
current of warın air, such as bicarbonate of soda, starch, and innumerable similar
substances, for all purposes where it is desired to bring a solid or pasty substance into
intimate contact with a gas or vapour, notably the manufacture of bleaching powder,
burning of dust, pyrites and the like. One great advantage of this apparatus is that
it produces very little dust when treating very light substances. Where great heat
is required external heat can be applied to the underneath surface of the trough, but
I prefer as a rule to supply any heat required by means of the air or gases passed
through.
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 :—
1. In apparatus for mixing, stirring or conveying fragmentary, granular, pulverulent
or pasty materials or for treating the same by gases, vapours, or other fluids, the
combination of two or more parallel or nearly parallel worms having intersecting
circles of rotation, geared so as to rotate synchronously, one worm being right-handed,
and the next left-handed, and so on in combination with a trough A, substantially as
and for the purposes described.
2. The manufacture and use for heating, drying or chemically treating materials
such as described in claim 1, by means of a gas or vapour, of apparatus consisting of
à chamber through which the material is passed by means of a stirring mechanism,
such as described in claim 1 in one direction, while the gas or vapour passes through
the chamber in the opposite direction.
3. The manufacture and use for the purposes of making bleaching powder or for
exposing substances such as described in claim 1 to the chemical action of gases or
other fluids, of a long closed chamber or trough in which two or more parallel or
nearly parallel worms or series of beaters having intersecting circles of rotation, and
geared and arranged as described, stir and remove the material to be acted upon,
thereby exposing it to the chemical action of the fluid confined in or passing through
the upper part of the chamber.
4. The manufacture and use for the purpose of heating, drying or desiccating
fragmentary, granular, pulverulent or pasty materials, of apparatus consisting of a
trough on the bottom of which rotate synchronously two or more parallel or nearly
parallel worms, or series of beaters, having intersecting circles of rotation, and arranged
so that a current of air (heated or otherwise) superheated steam or other hot gas or
vapour shall traverse the trough preferably in a contrary direction to that in which the
material to be dried or heated is passed through.
Dated this 18th day of March 1987
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Agents for the Applicant.