Improvements in Apparatus for the Complete Evaporation of Solutions.
Year: 1890

page_text: Date of Application, 6th Sept., 1890-Accepted, 18th Oct., 1890
COMPLETE SPECIFICATION.
Improvements in Apparatus for the Complete Evaporation of
Solutions.
I, HARALD EMIL HANSEN, of Raadhasstree de 5, Copenhagen, in the Kingdom of
Denmark, Pharmaceutical 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 :-
My invention relates to improvements in apparatus for the complete evaporation of
solutions. By means of the apparatus hereafter described, an exceedingly rapid evapora-
tion is obtained in vacuo of all kinds of solutions; and on account of the high vacuum
which ought to be employed, and the rapidity with which the evaporation takes place,
the product becomes of such a light and porous nature, that, e.g., in the evaporation
of malt extract, this does not need any actual pulverization, inasmuch as merely
grating it suffices to reduce it to a fine powder.
On the accompanying drawing is shewn such an evaporation apparatus in vertical
longitudinal section. The evaporation takes place on the inner as well as on the outer
side of a double-walled funnel a of sheet tin, or other equivalent metal, fixed on the
end of a hollow axle c by means of which a slow rotary motion is communicated
to it in a vacuum vessel h, the walls of which are at some distance from the walls of
the funnel a.
The vacuum vessel is fixed in a stand d. It is provided with :
(1) A pipe through which air and steam are sucked out by means of an air
pump or other contrivance.
(2.) Two pipes 9 and y, through which the solution by means of the vacuum is
sucked into the vacuum vessel & from suitable reservoirs. The pipe g' delivers the
solution on to the outside of the funnel a: the pipe g, delivers the solution on to the
inuer surface.
(3.) Three sight-holes h₁₂, h. The sight hole h, is provided with a lantern i for
lighting the interior of the vessel b, while h, and h, serve as sight holes for observing
the process of evaporation in the apparatus.
(4.) A man-hole which can be made air tight by means of a cover and screw
arrangement through which the remanent product can be taken out, and also the
apparatus be cleansed.
(5.) A vacuum gange p; a thermometer 9; a valve for admitting air, s; a valve
for admitting steam, ; à valve for admitting water, u. Through the hollow axle c
there passes a steam pipe n. This is prolonged into the space between the walls of
the funnel a, where it can be ramified in different ways. The drawing shews it
continued to the wide end of the funnel, where it forms a ring k, between the walls
of the funnel, along its edge. The pipe is provided with holes in order that the
steam can stream out from it, and spread itself in the hollow space between the funnel-
walls for the heating of the latter.
The condensed steam arising from the cooling process finds, during the revolution
of the funnel a, outlet through suitable holes in the end of the hollow axle c as well
as through this, and which therefore issues freely outside. The steam pipe n is, on
the contrary, outside the axle e, put in connection with a steam chest in the wall of
which the pipe can move in a gland during the revolution of the axle.
The axle e moves in two bearings of which, however, only one is shewn on the
drawing, and at the point it enters the vessel b a gland for the air-tight closing of the
vessel is placed.
For warming the funnel a by means of the pipe n, only waste steam is generally
used.
The rate at which the funnel a revolves is regulated by means of stauned driving

page_text: pulleys according to the consistency of the solution to be operated upon. Whilst
the solution steadily flows down the inner and outer surfaces of the funnel, it will
during the revolution of the funnel, follow on these, two spiral lines, whereby both
surfaces will become covered with a thin layer of solution which, by the warming of
the funnel and the high vacuum, will be subjected to a brisk evaporation. Tho
product will then bo leposited as a light porous mass. When this has reached a
suitable quantity, the supply of the solution from the pipes g, and g, is stopped by
means of cocks, but the evaporation is continued for some time longer, until it is
observed through the sight holes h, that to mass is completely dry,
и,
The air is then admitted into the apparatus; the manhole is opened; and, through
it, the dry mass, which has been scraped from the surfaces of the funnel is taken
out. It must be observed in conclusion, that the apparatus described can, of course,
be modified in several different ways without anything essential in the invention being
thereby altered; for instance, a double-walled cylinder in a sloping position can be
fixed in a similar manner as the funnel a instead of it. The pipes 91, can be provided
with roses if necessary.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is :-
Apparatus for the complete evaporation in raruo of solutions by means of which
these are caused to flow down the surface or surfaces of a horizontal or more or less
obliquely placed double walled funnel or cylinder a the inner and outer surfaces of
which are heated by admission of steam in the space between its walls, which funnel
or cylinder is placed in a vacuum vessel in which it can be set in rotation by suitable
пролив
Dated the 6th day of September 1890.
PHILLIPS & LEIGH,
22, Southampton Buiklings, Chancery Lane, W.C., Agents for the Applicant,