An improved Process and Apparatus for kenning sugar.
Year: 1888

page_text: An improved Process and Apparatus for kenning sugar.
We, CARL STEFFEN, of No. 2 Heugasse, in the City of Vienna, in the Empire of
Austria, Engineer, and CARL JACOB LANGEN of the Firm of F. Langen and
Hundhausen, of Grevenbroich, Germany, Engineer, do hereby declare the nature of
our Invention for "AN IMPROVED PROCESS FOR RAPIDLY REFINING SUGAR IN LOAF FORM
THROUGH THE COMBINED SYSTEMATIC OR SIMPLE PURIFICATION OF THE LOAVES WITH
PURE LIQUOR WITHIN THE FORM UNDER PRESSURE, SUBSEQUENTLY DRIVING OFF THE
SUPERFLUOUS LIQUID AND REGAINING THE SAME BY MEANS OF THE CENTRIFUGAL APPA-
RATUS AND THE APPARATUS FOR CARRYING THE PROCESS INTO EFFECT," and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement :-
The present method of purifying or refining sugar in loaf forms by pouring purifying
liquor onto the same is necessarily a very slow process and the separation of syrup
which drops from the forins is very imperfect. A large quantity of liquor is required
as the reemployment of the dropping off liquor can only take place in imperfect
manner and a large quantity of liquor is carried off in the raw syrup.
Another method consists in washing the loaves in centrifugal machines in such
manner that during the operation of the centrifugal machine liquor is led onto the
loaves and in this manner a purification of the sugar is effected. This process also
requires a large quantity of liquor while the same in consequence of its initial force
penetrates the mass in irregular manner and consequently the syrup is not only
imperfectly driven off but the washing liquor mixes with the syrup and thus causes a
larger quantity of liquor to be employed.
The regular driving off of the syrup adhering to the sugar crystals in the sugar loaf
can only be effected when the purifying liquor is passed through the said sugar loaf by
hydrostatic pressure.
Experiments made for purifying sugar loaves with liquor under pressure have up to
now given no useful result for the sugar industry, while on the one hand these experi-
ments were not systematically carried out and on the other hand the large quantity of
pure liquor remaining in the loaf is not removed quickly enough so that in this process
an improportionate large quantity of pure liquor would have to be employed.
The object of the present process is to purify sugar loaves with liquor under pressure
in partially or entirely systematic manner and to rapidly remove and regain the pure
liquor contained in the sugar loaf. This latter is effected by placing the loaf forms
with the washed loaves in a centrifugal machine by means of which the liquor is driven
off and the pure liquor recovered. This combination of treating loaf sugar in the
forms under hydrostatic pressure in a systematic or only partially systematic purifica-
tion and then driving off and regaining the pure liquor in a centrifugal machine is

page_text: new and by this combination of the two processes we have succeeded in purifying
sugar in loaves in a very short time and by employing a very small quantity of
purifying liquor.
This is a most important technical success for the reason that it has not been possible
to excente the rapid purification of sugar in loaves by employing a minimal quantity
of liquor. Experiments have proved that the quantity of liquor employed in our
improved process is less than half that employed in the purifying methods now in nse.
In order to carry our improved process into effect we proceed as follows:
The crystallise mass in the loaf form are in a washing apparatus in which the single
forms are provided with water tight covers which are in connection with a pressure
fale or pipe containing washing liquor. By means of this device the liquor is
contained in the space between the cover and the sugar loaf so that the pressure in the
service pipes will force the fluid equally through the entire mass of the sugar loaf and
out at the opening or nozzle in the apex of the loaf form. This liquor is carried off
through suitable troughs into collecting reservoirs for separating the syrup from the
washing liquor.
An entire system of such loaf form covers can be connected to a preferably
horizontally arranged pressure tube so as to form one apparatus whereby a large
number of sugar loaves can be simultaneously submitted to the purifying process from
the liquor in the tube or canal which said liquor is force I into the service by means of
a suitable force pipe. An apparatus of this kim is represented in the accompanying
drawings of which Fig. 1 is the elevation of two loaf forms connected to a hollow beam
by means of their water tight covers.
Fig. 2 represents the connection of the hollow beam containing the washing liquor
with the lo if forms arranged on each side of the same partly in elevation and partly in
vertical section.
Fig. 3 is a plan or top view of Fig. 1 partly in horizontal section through the
hollow beam.
Fig. 4 is an elevation of the cover to the loaf forms with the flange for attachment.
to the hollow hoain on an enlarged seale.
Fig. 5 represents the upper part of a loaf form with water tight cover and the liquor
carrying hollow beam in vertical section.
A is the hollow casting or bean containing the main supply pipe or canal a and the
lateral flange like extensions to which the flanges of the covers B to the loaf
forms are served. The hollow beam A and the loaf forms (attached to the same
are carried by the standards ) to which the troughs E for receiving the liquor passing
off from the tuyeres or nozzles e in the apex of the loaf forms C.
The pipe or canal a is in connection with a pressure tube or with a force pump so
as to produce the requisite pressure for forcing the liquor through the sugar loaves in
the forms. The cover B to each loaf form can be firmly pressed onto the latter by
means of the strap or bow and screw F (Figs. 1 & 5) so that the packing ring c¹ will
hermetically seal the upper part of the form said cover being provided moreover with
a canal d which communicates with the tube or canal a of the beam A.
A space remains in the loaf form between the inner surface of the cover B and the
top of the sugar loal for receiving the washing liquor which is under pressure and is
equably forced through the entire mass of the sugar loat. When the liquor has passed
through the sugar loaves it flows out at the nozzles e at the tips of the forms and is
led off into collecting vessels by the troughs where the syrup is separated from the
washing liquor. The washing or purifying of the sugar loaves in the form C is curriod
oul very rapidly in consequence of the pressure exerted on the liquor.
The aforedescribed apparatus can be employed to like advantage for one washing
or for the systematic washing of sugar loaves with purifying liquor.
Each connection between the main tube or ennal a in the hollow beam A and the
eunal in the covers B can be so arranged that the same can be opened or closed
according to requirement by means of suitable cocks or valves. According to
circumstances ie. whether the washing process is to be carried out in more or less
systematic succession two or more kinds of liquor are successively employed and

page_text: increasing in purity. These liquors are forced through the sugar loaves and after
separating out the syrup from the sugur crystals are recovered in similar volume,
after leaving the nozzles of the forms in collecting nozzles according to their increasing
purity so that the same can be employed in a further series of washings or purifyings
in our improved apparatus. From the foregoing it will be evident that the liquor in
each separate washing will remain for a certain period at a standstill, so that a more
or less perfect systematic washing can be effected in a purifying apparatus by means
of which the liquor acts under pressure on the hard crystallised mass of sugar in the
form.
As soon as the washing process is finished which will be seen by pure liquor passing
off from the nozzles of the loaf forms the pure liquor located between the upper surface
of the sugar loaf and the cover is driven off by means of compressed air or in other
suitable manner so that the surface of the base of the body no longer appears to be
wet and the said loaves can be removed without loss of liquor.
In order to remove the liquor from the loaves so treated as above described for fully
drying the same and regaining the liquor remaining in the sugar mass of the washing
process, the sugar loaf forms are treated in a suitable centrifugal machine.
The pure liquor which is thus separated out of the mass of sugar in the loaf form
is employed for treating a further quantity of sugar loaves whereas the dried loaves
are treated further in well known manner.
Having now particularly described the nature of our said invention and in what
manner the same is to be performed we declare that what we claim is —
1. A process for the rapid treatment of loaf sugar characterised by the combination
of the systematic or partially systematic or simple washing of loaf sugar within the
loaf forms under pressure with the centrifuging of the washed or purified mass of
sugar in appropriate centrifugal machines for driving off and regaining the pure
washing liquor passing off from the purified sugar loaves substantially as and for the
purpose set forth and shown on the drawings.
2. Driving off the pure washing liquor out of the apparatus and the loaf forms when
the process is finished by means of compressed air, substantially as and for the purpose
set forth and shown on the drawings.
3. An apparatus for washing or purifying sngar loaves in the form and under
pressure as given in claim 1 characterised by
a) Attaching the covers B for the loaf forms C to a common hollow beam or
tube a acting as supply pipe for the washing liquor in such manner that this
hollow beam or tube is in connection with an entire system of loaf forms.
6) The water tight closing of each of the loaf forms by a cover B so as to leave
a free space between the inner surface of the cover and the base of the sugar
loaf in the form C in order that the washing fluid led into the same from
the tube or canal a through the canal d in the cover B can be forced with
equable pressure through the entire mass of the sugar loaf in the form whereas
the washing liquor flowing from the nozzles c of the forms is caught in troughs E
substantially as and for the purpose set forth and shown on the drawings.
Dated this Fifth day of July 1888.