An Improved Method and Apparatus for Drying Aqueous Matters.
Year: 1890

page_text: COMPLETE SPECIFICATION.
An Improved Method and Apparatus for Drying Aqueous Matters.
I REGINALD HADDAN of the firm of Herbert & Co. Patent Agents of 18
Buckingham Street, Strand W.C. in the County of Middlesex, Civil Engineer
do hereby declare the nature of this invention, a communication to me from abroad
by Emil Passburg of Breslau in the Empire of Germany Engineer, 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 in an improvement in the method of drying aqueous
materials which is described in the specification of Letters Patent No. 6326 of 1884
and in apparatus modified in the manner hereinafter described for carrying out the
improved method.
Under said patent matters were dried by juxtaposition of said matters with heat
reservoirs made of or with sand or other substances described in the specification
thereof, which had been previously heated.
According to this improved method the heat reservoirs are intended to be such that
they can be heated when already in juxtaposition with the matters to be dried, or so
that, during the process of drying the heat may be maintained within the reservoirs
for a time before thay are allowed to cool down under the influence of conduction and
radiation.
In the drawings hereunto annexed
Fig. 1 is a vertical longitudinal section of a drying chamber fitted with trays for
the materials and the improved heat reservoirs.
Fig. 2 is a vertical cross section thereof with trays removed.
Fig. 3 is an elevation of the door thereof.
Fig. 4 a horizontal cross section of the apparatus showing the interior of a heat
reservoir.
The vacuum steam drying apparatus A represents a hermetically closing chamber
which by pipe B is connected with a condenser and an air pump. In place of heated
sand boxes or fire tiles, closed steam chambers Care used these chambers being
formed by the metal frame a with sheets b welded to it on both sides.
This frame is perforated on two sides and to the holes so formed are fixed on one
side the steam inlet pipes r and on the other side the steam outlet pipe r¹.
Instead of this quadrangular apparatus as shown an apparatus of a different shape
may be used, it may be a cylinder for instance surrounded by a steam jacket the metal
sheets may be welded to the walls of the cylinder and the same perforated at places
whereby the steam chambers C are formed.
In other words the shape of the apparatus has no influence upon the working of the
process set forth as long as the apparatus described is an air tight reservoir within
which are formed steain chambers in order to conduct heat to the substances to be
dried which are laid out on trays crates or the like d whilst outside the steam chambers
a vacuum is established. In order to feed the apparatus, the door T is opened, and
the metallic trays d which carry the substance to be dried are placed upon the steam
chambers C. The door is then closed, and the air pump is attached and operated to
remove the vapours from the apparatus. As soon as the material treated begins to
dry, the steam valve or valves for pipes r is closed to prevent the material becoming
heated too much.
A convenient gauge m and thermometer n are fixed as shown.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The improved method of drying 'aqueous materials in vacuo by means of heat

page_text: reservoirs in juxtaposition with the matters to be dried whereby the heat may be
transferred to the reservoirs, being steam or. hot vapour chambers whilst the matters
are in juxtaposition therewith and whereby the temperature of said heat reservoirs may
be maintained for an indefinite time.
2. The construction of a drying chamber with steam compartments or vessels
therein adapted to support trays of aqueous matters to be dried and to be supplied with
steam for drying said matters by heat, by conduction and radiation, with means
for creating and upholding a vacuum or diminished pressure in said drying chamber
about said vessels for the purpose set forth.
Dated this 26th day of June 1890
HERBERT & Co.,
18. Buckingham Street, Strand, London, W.C., Agents for Applicant.