Improvements in Apparatus for Filtering Beer and other Alcoholic and Gaseous Liquids.
Year: 1892

page_text: 'Date of Application, 2nd May, 1892-Accepted, 9th July, 1892
COMPLETE SPECIFICATION.
Improvements in Apparatus for Filtering Beer and other Alcoholic
and Gaseous Liquids.
I, HEINRICH GEHRKE, of 3 and 4, Zimmerstrasse, Berlin, in the Empire of
Germany, Manufacturer, do hereby declare the nature of my 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 apparatus chiefly designed for filtering beer whereby a
larger filtering surface is afforded in a given space than has hitherto been the case
and the apparatus can be turned without its being necessary to loosen any hose or
pipe connection, the 'filtered beer being drawn from a special chamber or basin
situated below the apparatus, not surrounded by the filtering layers, that is to say
at the place at which the beer first comes to rest, this being done with the object
of avoiding the formation of froth and the separation of gases during the
transmission of the beer which has been drawn of from the settling vats through
the filter into 'the vessels in which it is to be despatched and also to obtain the
last drops of the contents of the apparatus in a filtered condition.
In the accompanying drawing,
Figure 1 is a vertical section of an apparatus for filtering beer constructed
according to my invention; 'the layers of filtering material being removed.
Figure 2 is a section on the line of Figure 1, shewing the upper part of the
casing of the apparatus as seen from within.
Figure 3 is a similar section on the line of Figure 1 and
Figure 4 is a section on the line zz of Figure 1.
yy
Figure 5 is a horizontal section on the line xx of Figure 1 shewing the filtering
apparatus with the layers of filtering material in position.
The improved apparatus comprises a cylindrically formed casing A, the open
sides of which are closed by covers a, a (Figures 2 and 5). The cylindrical
casing A is provided on its outer surface with various subsidiary fittings, of
which 'b allows of the entrance of the unfiltered beer, conducted through the
supply pipe through the channels n, n, n (Figures and 5) into the filtering
chambers c, c, c (Figure 5).
"
"The beer finds its way out of the chambers c, c, c through the filtering
layers m, m, m into the filtering chambers c', c' and flows through the channels o, o
(Figures 3. and 5) into the reservoir e (Figures 1, 3 and 5) situated upon the
outside of the apparatus. From the reservoir e placed outside the apparatus
the beer reaches the outlet & through the flat tube p (Figures 1, 2, 3 and 5). The
subsidiary fittings (Figures 1 and 4) and g (Figures 1 and 3) constitute the
connection of the gauge-glasses h and i, for the unfiltered beer by the channels r
(Figures 1, 2 and 4) and for the filtered beer by the channels 9 (Figures 1, 2
and 3) as well as that of the pressure gauge with the interior of the apparatus.
In the interior of the apparatus are filtering plates m, m so arranged as to
constitute chambers c, c, c for the unfiltered beer and c', c¹ for the filtered beer,
and the relation of these chambers to one another is such that each division c¹ is
situated between two divisions c, c, and separated from the latter by the filtering
plates.
The subsidiary fitting b is provided with passages n which lead into the
divisions c, c, c for the unfiltered beer.
The reservoir e placed at the lowest point outside the filtering apparatus is

page_text: connected by two channels o, o with the divisions c', c' for the filtered liquid which
first comes to rest in it.
The connection between the reservoir e and the arm & for drawing off is effected
by a tube p carried through the middle filtering chamber c. The subsidiary
fittings and d are hollow, being thus constructed that they may also serve as axes
of rotation for the apparatus A.
The connection of the gauge glass and the subsidiary fitting for the unfiltered
beer is effected by the channels r, r, that of the gauge glass and fitting g for the
filtered beer by the channels q, I-
The way in which the filtering apparatus works is as follows:—
The beer which runs from the settling vat under pressure through the pipe 6' to
the fitting flows through the passages n, n, n into the filtering chambers c, c, c
and passes as it is pressed through the filtering plates or filtering substances m, m, m
into the filter chambers c', c' from which it proceeds through the channels o, o out
into the draw-off channel or draw-off chamber e at the lowest part of the casing of
the apparatus (Figure 5). Here the beer first comes to rest and is thence drawn
out by means of the pipe p, which is carried through the central filtering chamber c
to the draw-off arm d, into the vessels in which it is to be despatched.
As the result of the peculiar arrangement of the subsidiary fittings b, d, e, on
the outer surface of the apparatus it is however in addition rendered possible to
secure a greater extent of filtering surface than hitherto in a limited space from
the fact that the chambers c', c¹ for the filtered liquid are separated on both sides
from the chambers c, c, c for the unfiltered beer by filtering substances m, m, m, m.
Another object however is attained by the greater filtering surface, vis. :—a
saving of pressure, whereby again it is rendered possible to obtain a sufficiently
large amount of filtered liquid even from vats which are old and weak.
The filtering substances possess capillary force, the greater the extent of filtering
surface the greater the quantity of filtered liquid obtained by capillary force.
The greater the amount of filtered liquid produced by the capillarity, the less will
be the amount required to be produced by the effect of pressure (compressed air,
hydrostatic pressure). In practice the matter stands thus :-
If the
One or several extractors produce a given amount in a given time.
filtering surface be very small, the pressure must be very great, if the filtering
surface be very great the pressure need only be very low, in order to obtain a given
quantity in a given time by pressure through the filtering surfaces.
The arrangement of filtering chambers may of course be used in the reverse
order. Since in this apparatus the filtered and unfiltered beer are under one and
the same pressure, which is also that which exists in the settling vat and since
morcover the filtered beer is drawn off at the lowest point, at which it first comes
to rest, all frothing during the drawing off is avoided and the last drops of the
contents of the filter are likewise obtained.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A vertically working filtering apparatus for beer and other alcoholic and s
gaseous liquids distinguished by the employment of more than two independently
acting filtering substances m, m in a common space A in combination with the
hollow axes b, d serving for the admission and drawing off of the liquid the former
axis being connected by channels n, n, n with the interior of the apparatus, and
the latter by a tube p with a collecting reservoir e arranged outside the apparatus 5
at the lowest point of the latter and not enclosed by the filtering surfaces, by
which arrangement a relatively large amount of filtered liquid is obtained in a
clear and froth-free condition to its very last drops, and the apparatus may be
turned every time without previously loosening any tube or pipe connections,
substantially as hereinbefore described.

page_text: 2. The improved apparatus for filtering beer and other alcoholic and gaseous
liquids hereinbefore described and illustrated in the accompanying drawing.
Dated the 2nd day of May 1892.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.