Iм- PROVEMENTS IN RefininG SUGAR
Year: 1877

page_text: LETTERS PATENT to Franz Otto Matthiessen, of Irvington, State of New
York, United States of America, Sugar Refiner, for the Invention of " Iм-
PROVEMENTS IN RefininG SUGAR,"
Sealed the 26th May 1877, and dated the 5th April 1877.
COMPLETE SPECIFICATION filed by the said Franz Otto Matthiessen at the
Office of the Commissioners of Patents on the 5th April 1877.
FRANZ OTTO MATTHIESSEN, of Irvington, State of New York, United States of
America, Sugar Refiner. "IMPROVEMENTS IN REFINING SUGAR."
My improvement relates to the art of removing impurities from raw sugar by
washing.
It has heretofore been a common practice to wash raw sugar for the purpose of
removing its soluble impurities preparatory to boiling it in the vacuum pan, and
this washing has usually been performed in the centrifugal machine. In the latter
case the raw sugar is mixed with a comparatively small quantity of water, so as
to make it of the consistency of magma, and in this condition when subjected to
the action of the centrifugal machine it forms a wall on the inside of the periphery
of the basket, and while in that condition is washed by water or steam introduced
into the centrifugal machine, and directed in jets toward the sugar wall. The
water or steam so used is driven through the wall of sugar by centrifugal force, and
carries with it the soluble impurities contained in the sugar.
The water used in washing the raw sugar dissolves and carries off a portion of
the sugar, thus forming a syrup which is dark colored by reason of the impurities it
contains. It has heretofore been the practise to treat this syrup by decolorizing
and boiling in the usual way to extract the sugar therefrom.
My Invention consists in using this syrup instead of pure water for the purpose
of imparting the desired fluidity to the raw sugar preparatory to its introduction
into the centrifugal machine, as has been described.
The syrup or washings from the raw sugar may be used over and over again a
greater or less number of times, according to the quantity of impurities contained
in the sugar operated upon. Finally, when by repeated use the syrup has become
very black and thick I treat it by the usual processes of decolorization and boiling

page_text: to extract the sugar it contains, and recommence the washing operation with pure
water as before.
The advantage of this process of washing raw sugar is twofold,-
First. The syrup having already taken up all or nearly all the sugar which it
can hold in solution does not dissolve and carry off any considerable portion of the
raw sugar.
Secondly. I obtain the impurities from the raw sugar in a concentrated form,
that is, in a small quantity of syrup, which can be conveniently treated by the
subsequent process of decolorization and boiling.
In my process the sugar is prepared for washing in the centrifugal machine by
being mixed with the syrup resulting from a previous washing or washings of raw
sugar, and being then placed in the centrifugal machine is there washed by the jets
of water or steam in the usual way, and the syrup discharged from it is collected,
and can be used to mix with another lot of raw sugar. This use of the syrup is
repeated so long as the syrup has sufficient fluidity to answer the desired
purpose.
Of course I may use any sugar, syrup, or sugar liquor for preparing raw sugar
for washing with a like effect as to rendering the raw sugar fluid without dis-
solving any considerable portion of it.
I claim as my Invention, the improvement in the mode of removing impurities
from raw sugar, herein described, which consists in preparing the raw sugar for
washing in the centrifugal machine by mixing it with a sugar syrup or sugar liquor,
substantially as and for the purposes set forth.
In witness whereof, I, the said Frauz Otto Matthiessen, have hereunto set
my hand and seal, this Thirteenth day of March, A.D. 1877.