THE APPLICATION OF GRAVEL AND CERTAIN OTHER MATERIALS, INSTEAD OF BONE CHARCOAL, FOR THE PURPOSE OF FILTRATION IN THE REFINING OF SUGAR
Year: 1880

page_text: LETTERS PATENT to Henry Springmann, one of the Firm of Carl Pieper, Civil
Engineer and Patent Agent, of 109-110, Gneisenaustrasse, Berlin, S.W.,
Prussia, for an Invention of "THE APPLICATION OF GRAVEL AND CERTAIN
OTHER MATERIALS, INSTEAD OF BONE CHARCOAL, FOR THE PURPOSE OF
FILTRATION IN THE REFINING OF SUGAR." A communication from Georg
Friedrich Meyer, Doctor of Philosophy, of Brunswick, in the Duchy of
Brunswick.
PROVISIONAL SPECIFICATION left by the said Henry Springmann at the
Office of the Commissioners of Patents on the 10th August 1880.
HENRY SPRINGMANN, one of the Firm of Carl Pieper, Civil Engineer and
Patent Agent, of 109-110, Gneisenaustrasse, Berlin, S.W., Prussia. "THE
APPLICATION OF GRAVEL AND CERTAIN OTHER MATERIALS, INSTEAD OF BONE
CHARCOAL, FOR THE PURPOSE OF FILTRATION IN THE REFINING OF SUGAR." A
communication from Georg Friedrich Meyer, Doctor of Philosophy, of Brunswick,
in the Duchy of Brunswick.
In sugar refineries the solution of raw sugar has hitherto always been filtered by
means of bone-charcoal for the purpose of purifying it of colouring matter and
other foreign substances which have remained in the same after the previous
treatment by lime, &c.
According to experiments made by my correspondent, other and far cheaper
materials may be employed instead of bone-charcoal without impairing the quality
of the sugar to be obtained.
As materials suitable for this purpose are to be named the following:-Coarse
sand or fine gravel, silicate rocks insoluble in water, quartz, mineral coal, including
anthracite, cokes, peat-charcoal, minerals having alkaline carths as their base, and
being practically insoluble in water; as for instance, sulphate of baryta, limestone,
dolomite, and like substances; moreover, broken porcelain, and crockery ware and
other artificial silicates, and, finally, slag-hair. Such of these materials as originally
occur in lumps or large pieces have to be reduced to a granular state of the requisite
fineness.
The said materials after having been in use for a certain time are washed out by
means of diluted muriatic acid and water, whereupon they may be employed
again,

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Springmann in the Great Seal Patent Office on the 7th
February 1881.
THE
HENRY SPRINGMANN, one of the Firm of Carl Pieper, Civil Engineer and
Patent Agent, of 109-110, Gneisenau Strasse, Berlin, S.W., Prussia.
APPLICATION OF GRAVEL AND CERTAIN OTHER MATERIALS, INSTEAD OF BONE
CHARCOAL, FOR THE PURPOSE OF FILTRATION IN THE REFINING OF SUGAR." A
communication from Georg Friedrich Meyer, Doctor of Philosophy, of Brunswick,
in the Duchy of Brunswick.
In sugar refineries the solution of raw sugar has hitherto always been filtered by
means of bone-charcoal, for the purpose of purifying it of colouring matter,
saccharate of lime, organic salts, and other foreign substances which have remained
in the saccharine solution after its treatment by lime &c.
Bone-charcoal is universally used for this purpose, because it is the prevalent
opinion that the saccharine liquor has not only to be purified mechanically by the
filtration, but that the filtering substances have to act chemically on the same, if
white loaf-sugar of good quality and in satisfactory quantity is to be obtained.
According to experiments made by my correspondent other and far cheaper
materials may however be employed instead of bone-charcoal, without impairing the
quality or reducing the quantity of the sugar to be produced.
As materials suitable for the said purpose may be named the following:-Coarse
sand or fine gravel, quartz in all its varieties, silicate rocks insoluble in water,
mineral coal, including anthracite, cokes, peat-charcoal, minerals having alkaline
earths at their base and being practically insoluble in water, as for instance,
sulphate of baryta (heavy spar), limestone, and dolomite; moreover broken
porcelain, crockery-ware, thoroughly burnt bricks, and other insoluble artificial
silicates, among which is yet to be mentioned slag hair. The materials to be
employed must possess the necessary cohesion, so as not to be crushed during their
use, and such of them as originally occur in lumps or large pieces have to be
reduced in a suitable manner and thereupon to be sifted (the latter process being
also ordinarily required with regard to the gravel or sand), so that a granular mass
is obtained, the particles of which are by preference not smaller than a millet-grain
and not larger than a pea. The material, after having been washed, is brought
into the filtering-vessels in the same manner as hitherto practised with regard to
the bone-charcoal. When after a certain time the liquor passing through the filter
begins to appear turbid, the filter is emptied, and the gravel, &c., is brought into
reservoirs plastered with cement, or into other suitable vessels, whereupon it is
washed at first with diluted muriatic acid, and subsequently with pure water,
which has to be renewed several times. The material may thereupon be used
again.
The filters filled with the said materials (and which may in general be termed
gravel-filters) are either employed alone and with the exclusion of bone-charcoal
filters, or they are used in combination with the latter, so that only a certain
number of the bone-charcoal filters heretofore used in a sugar-refinery are replaced
by gravel-filters.
The advantages which the use of the said filtering materials instead of bone-
charcoal presents are the following:
--
Firstly. These materials are far cheaper.
Secondly. The cleansing process to which they have to be submitted from time
to time is far less expensive than the revivification of the bone-charcoal.
Thirdly. The quantity of water remaining in the non-porous materials after
having been washed is less than the amount which, on account of its porosity, the

page_text: bone-charcoal absorbs when steam is passed through the filters before they are filled
with liquor; the latter therefore becomes less diluted.
Fourthly. The non-porous materials retain less saccharine liquor at the end of the
filtering process, and this remaining quantity may be washed out even more
completely with a smaller quantity of water, so that on this account also less water
(which has to be evaporated again) enters into the liquor.
The saving resulting from these causes, principally however from the first and
second, may amount to above 4 percent, of the entire manufacturing expenses.
Having thus described the nature and object of this Invention, and the manner
in which it is to be carried into practice (as communicated to me by my corre-
spondent), I hereby claim as the new and important feature of the same,-
The use of sand or gravel, of quartz, silicate rocks insoluble in water, mineral
coal, including anthracite, cokes, peat-charcoal, minerals whose base consists of
alcaline earths, and which are practically insoluble in water, such as heavy spar,
limestone, and dolomite; moreover of broken porcelain, crockery-ware, thoroughly
burnt bricks, or other insoluble artificial silicates, or of slag hair, instead of or in
combination with bone-charcoal, for the purpose of filtering saccharine liquor in
sugar-refineries, substantially as herein before described.
In witness whereof, I, the said Henry Springmann, have hereunto set my
hand and seal, this Twenty ninth day of January, in the year of our Lord
One thousand eight hundred and eighty one.
HENRY SPRINGMANN. (L.S.)