A NEW AND USEFUL PROCESS AND APPARATUS FOR THE EVAPORATION OF LIQUIDS AND THE DRYING OF EMULSIONS AND FECAL MATTER
Year: 1882

page_text: LETTERS PATENT to Adalbert baron of Podewils Engineer of Munich in the
Kingdom of Bavaria (German Empire) for an invention of A NEW AND
USEFUL PROCESS AND APPARATUS FOR THE EVAPORATION OF LIQUIDS AND
COMPLETE SPECIFICATION filed by the said Adalbert, Baron of Podewils
at the Office of the Commissioners of Patents on the 31st August 1882.
ADALBERT baron of Podewils, Engineer, of Munich in the Kingdom of Bavaria,
(German Empire,) A NEW AND USEFUL PROCESS AND APPARATUS FOR THE
EVAPORATION OF LIQUIDS AND FOR THE DRYING OF EMULSIONS AND FECAL
MATTER
The object of my invention, as the title indicates, is to devise a process and
suitable apparatus for the purpose of effectively evaporating liquids and drying
emulsions and fecal matter. In the elucidation of my invention, in order to
present the same more clearly, reference will be had to the accompanying drawings
forming a part of this specification.
The apparatus shown in Figures 1 a to 6b purpose the concentration of such
liquids as leave behind, when evaporated, sediments which usually attach
themselves to the heating surface and diminish the effect of the heat by such
incrustation. At present, stirring apparatus is employed which is intended, during
the process of evaporation, to keep such liquids as have solid substances suspended
in them, in motion, and used especially in breweries, but these are unpractical.
In my apparatus, as shown in the said figures, are provided scraping gears with
fixed or elastic scrapers which either continually or periodically graze the heating
surfaces and thus prevent the formation of incrustations upon them. In the
drawings, the scraping gears are marked C, the heating surfaces H, the steam
admission pipe E and the eduction pipe for the water of condensation S. The
evaporators are shown as cylindrical boilers, horizontal or vertical, and provided
with a scum-cupola. The heating surfaces are set in the boilers independently,
and consist either of straight plates with double walls as shown in Figures 1 a, 6
Din Q.71

page_text: This
and 5 a, b, or of bent plates as shown in Figures 4 a, b or of a system of tubes as
shown in Figures 2 a, b and 3 a, b. The heating surfaces of the evaporators shown
in Figures 1 a to 4b are completely immersed in the liquid to be evaporated,
while those of the evaporator shown in Figures 5 a, b receive the fluid from above
by a suitable mechanism shown in the drawing as a system of pails s. In the
apparatus shown in Figure 5, the scraping gears fit exactly between the horizontal
plates H, and push the liquid from one plate to the other and finally into the
lower funnel t from out of which the concentrated liquid is removed from time to
time. Figures 6 a, b show an evaporator heated directly by fire-gases which pass
under the boiler through the canals K. The scraping-gear C is spirally curved
and thus favors the forward motion of the sediment toward the eduction pipe S¹
in the apparatus. The apparatus shown in Figures 7 a to 10 are devised for the
purpose of reducing the concentrated liquids or emulsions to a state of complete
dryness without the admixture of any drying substances. They consist of ring-
shaped or square plates p with double walls on which the emulsion is poured in
layers of uniform thickness, and after being completely dried without any
mechanical means, merely by the effect of steam introduced among the plates, the
dry residue is scraped off by a suitable mechanism or cut away by a rotating
knife. The thickness of the layer on the plates is made variable by a relative motion
of the plates and the admission pipe b while the liquid is being poured on.
relative motion is easily effected by means of a plate rotating or pushed forward
under a stationary pipe as well as by the same movement of the admission pipe
over a stationary plate. Figures 7 a, b represent a simple apparatus with only one
plate p, shown in section and plan. The scraping gear consists of several single
knives d with a uniform pressure upon them transmitted by springs or balance
beams which are fitted into the arm G, but not shown in the drawing, so that the
knives can easily adapt themselves to the surface. The knives are fixed to the
rotating admission pipe 6 through which the liquid is poured on the surface,
in consequence of which arrangement the spot cleaned by them at once receives a
fresh supply of liquid. The dried residue is pushed outward by the obliquely
fixed knives into the discharge-canals e. The apparatus is kept in motion by
a worm and wheel r. The emulsion to be dried passes through the pipe f
provided with a stuffing box, into the axle A and thence into the admission pipe b.
Figures 8 a to 10 show an apparatus with a number of plates p arranged one above
the other. They are not quite ring-shaped but are provided with notches a
as shown in Figure 8 b. The roller-arm B on which the arm G with the knives
and also the admission pipe b are mounted, likewise carries upon it the guide-
roller which runs on the table ¹ screwed to the plates p. The arm G with the
knives is carried by the guide-roller f¹ from one story to the other by the turning
of the axle A which glides freely up and down in the key-grooves of the nave q
of the wheel and in the bearing m. The guide-roller f¹ is drawn in Figures 9 and
10 on a larger scale. Figure 9 shows its position and that of the arm G with the
knives & and the admission pipe in the descending moment, and Figure 10 in
the ascending movement. In the descent, the weight of the axle A presses upon
the knives d, and the roller f' is set free, while in the ascent the knives d are
upraised from the plates p, and the weight of the hollow axle A reposes upon the
roller f. The roller is turned down and raised up by convenient ledges or
detents i, as shown in Figure 8 a, at the upper and lower ends of the movement.
The change of direction is obtained by the well-known mechanical device of an
open or crossed strap z as shown in Figure 8 a. The emulsion is poured by
suitable means, such as a small bucket wheel s into the pipe g, from where it
passes into the hollow axle A and the admission pipe b. The latter is provided
with a faucet which by means of a cross H¹ and detents n, as shown in Figure 8 b,
is so steered or operated that the pipe b remains closed as long as it moves above
the notches a of the plates. The residue is forwarded by the knives into the
funnel e.
The developed steam escapes through pipes D. The admission of the
heating steam among the plates p is through the pipe E. The exit of the water

page_text: of condensation is through the pipe S. The table upon which the roller fi runs,
may of course be secured somewhere outside of the drying apparatus, above or
below.
Having thus described my invention, what I claim is:
First Apparatus for the evaporation of liquids at various degrees of pressure
or vacuum by means of heating surfaces kept free from incrustation by fixed or
elastic scrapers, substantially as described.
Second The process of separating solid substances from liquids by means of
steam heated plates with doubles walls on which the liquid is poured in a
uniformly thin layer, and after evaporation to dryness, the removal of the residue
by a device attached to the admission pipe, substantially as described.
Third-The regulation of the thickness of the layer of the emulsion by a
relative motion of the admission pipe and the plate, substantially as described
and for the purpose set forth.
Fourth Apparatus for the drying of emulsions, substantially as described.
In witness whereof I the said Adalbert, baron of Podewils, have hereunto set
my hand and seal this twenty-eighth day of August A.D. 1882.
ADALBERT baron of PODEWILS.
(L.S.)