Improvements in or relating to the Production of Sugar.
Year: 1896

page_text: Date of Application, 9th Dec., 1896-Accepted, 6th Feb., 1897
Improvements in or relating to the Production of Sugar.
A communication from L. JANSSENS & Co., of 99 Chaussée d'Anvers, Brussels, in
the Kingdom of Belgium, Sugar Refiners.
I, ALFRED JULIUS BOULT of 111 Hatton Garden in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :---
The present invention relates to improvements in the production of sugar, and
consists in the combination of different processes and has for its object to lessen
the time occupied in the process and to increase the yield of sugar.
The present process, as far as regards the treatment of raw sugar and the covering
process, differs from the hitherto known centrifugal process, in that only a simple
centrifugal process takes place, in this invention, without the quality of the product
obtained being lowered.
That part of the process, which relates to the further treatment of centrifugal sugar
by mixing it with ground sugar, is not new in itself, but the pressing process for
moulding sugar is totally different from processes used hitherto.
The new process is as follows:-
The raw sugar is at first ground or crushed and then passed through a sieve or a
bag, a yield of approximately 20 to 30% of very finely ground sugar with hardly any
perceptible grain and about 70-80% of fine granular sugar being obtained. Any
desired quantity of the finely ground sugar is dissolved at a temperature of 30 to
70° C., whereby a concentrated liquor is obtained which is decolourised by being
passed through a filter apparatus or a bag-filter.
The above mentioned fine granular sugar is covered by this liquor the proportion
being 65 to 70% of the former and 30 to 35% of the latter, both being heated, and
then it is machined in the centrifugal machine, whereby a beautiful crystalline sugar
with fine grain and a uniform amount of water, of about 2 to 4% is obtained. The
liquor being heated, during this operation, to 60° C., attains its maximum density and
crystallises more or less with the sugar. Owing to this and to the amount of water in
each 100 kilograms of raw sugar, 105 to 110 kilograms are obtained by machining.
The syrup coming out is, in the well known manner, again mixed with the liquor and
again used for covering.
To the sugar, obtained by machining, which is porous and loose, is added in the
well-known manner ground sugar in the proportion of 20 to 30% according to the
proportion of water in the sugar, said ground sugar filling up the pores of the fine
granular centrifugal sugar and giving the latter a beautiful white appearance.
Although the product so obtained is a little duller than the crystalline sugar, still the
difference is not important enough to constitute a draw-back.
The moulding of the product thus obtained is finally effected by the sugar being
compressed by machines constructed somewhat in the manner of briquettes presses, or
by pressing it by hand or otherwise. To prevent deformation of the plates containing
the sugar the process according to the present invention is as follows:-On the
bottom of the mould is placed a wooden plate of any desired thickness and on it
an equally thick plate of zinc or steel, on which the sugar is then placed and which

page_text: is little influenced by changes of temperature. After pressing, the plates together
with the sugar are removed from the mould and placed into the drying chamber
where the plates of sugar in 1 to 2 hours become sufficiently hard to be able to be
placed on a wooden frame to be completely dried.
The cracking of the sugar loaf which often occurred with the wooden supports,
hitherto generally used, in consequence of the deformation of the latter, is completely
avoided in the present process by the use of metal plates as support.
The present process occupies when using sugar grinding machines as now in use,
only about 18 hours and the product obtained, if liquor as clear as water has been
used, is perfectly white and pure. For each 100 kilograms of raw sugar treated
only 5% of ground sugar and syrup are necessary.
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me by my foreign correspondents, and in what manner
the same is to be performed, I declare that what I claim is :-
The process of refining raw sugar consisting in covering 65 to 70% of ground
and sifted raw sugar and fine granular sugar with 35 to 30% of concentrated
liquor produced at a temperature of from 30 to 70° C., the product obtained by
subsequent heating and machining after it has been mixed with from 20 to 30%
of ground sugar (according to the amount of water in it) being pressed in moulds
having interchangeable wooden supports, on which are placed metallic plates,
substantially as and for the purpose described.
Dated this 9th day of December 1896.
BOULT & WADE,
Agents for the Applicant.