Improvements in Bleaching and Dressing Grain, and in Apparatus therefor.
Year: 1896

page_text: Date of Application, 29th June, 1896-Accepted, 8th Aug., 1896
COMPLETE SPECIFICATION.
Improvements in Bleaching and Dressing Grain, and in Apparatus
therefor.
I, JOHN MILNE, of 1, St. Mary's Place, Inverurie, in the County of Aberdeen,
Scotland, Merchant, 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 :-
This invention relates to improvements in the bleaching and dressing of grain,
and to apparatus therefor. Hitherto the bleaching or whitening of grain has
generally been effected by means of sulphurous acid gas either on a common flat
kiln, or on a perforated zinc floor under which sulphur is burned, both these
methods requiring manual labour to load and unload the floors, during which
loading and unloading the workmen are liable to inhale sulphurous acid gas.
According to my invention the sulphur is burned in an iron tray to which it is
advantageously fed by a hopper and the sulphurous acid gas formed is carried by a
pipe to a fan which blows it one or more times through a descending column of
grain. This kills all moulds and microbes and improves the appearance and keeping
quality of the cereal.
The grain is, farther in its descent, passed through a horner, polishing machine,
or grader, and fan, and can be received into bags, thus completing the bleaching,
horning, polishing, grading, and dressing at one operation.
As by my process the sulphurous acid vapour can be made to pass more than
once through the grain, less of it is required than by the aforesaid kiln process. In
practice I find it advantageous to form the boxes or chambers through which the
sulphurous acid is forced, of rectangular shape with slanting louvre wooden boards
arranged in Venetian-blind form, but they may be made circular, oval, or oblong,
and may be of iron, lead or other material.
In the accompanying drawing I have represented apparatus for bleaching and
dressing grain according to my invention.
a is a chamber in which the sulphur is burned; b is the hopper having at its
lower end means for regulating the quantity of sulphur used; and c is the tray or
pan into which the sulphur is fed by the hopper and where it is burned. d is the
pipe leading from the chamber a and designed to conduct the sulphurous acid gas,
formed by the combustion of the sulphur, into the fan which draws the said gas
and passes it into the lower sulphurous acid box e. From there it is forced through
the louvres forming the sides of the box e, through the grain, which drops down
the box or chamber f, then between the louvres forming the sides of the grain
box and through the passages g, ginto the pipes h, which conduct it to the
upper sulphurous acid box i, whence it passes through the sides of the box i, the
descending grain, and escapes through sides of the box and the passages j, j to
the spent sulphurous acid exit k. is an elevator by means of which the grain is
lifted to the top of the chamber f. m is the horner or polisher, n is the fan, and o
a grain overflow pipe. The grain box f is kept nearly full when the apparatus is
at work. In the drawing the full line arrows indicate the direction in which the
grain falls and the dotted line arrows shew the path taken by the sulphurous
acid gas.
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 The described improvements in the bleaching and dressing of grain by means

page_text: of sulphurous acid gas, such improvements consisting in blowing the sulphurous
acid through the grain one or more times as it falls through a box or chamber and
in then passing the grain through a horner or grader substantially as, and in the
manner, hereinbefore described.
2. Apparatus for carrying out the process described in Claim 1, comprising a
chamber in which the sulphur is burned and from which the sulphurous acid gas
formed is blown by a fan or the like into a box or chamber having its sides formed
of inclined plates or louvres, the said box being enclosed in a second box also
having its sides formed of inclined plates or louvres, the grain dropping down in
the space between the two boxes, substantially as described.
3. Apparatus of the kind described having a sulphur chamber connected by
means of a pipe to a lower sulphurous acid box the sides of which are formed of
inclined plates or louvres and which is connected by means of passages with an
upper sulphurous acid box the sides of which are also formed of inclined plates or
louvres and which is in connection with an outlet pipe by means of suitable passages,
the two sulphurous acid boxes being enclosed in a grain chamber or box, having its
sides formed of inclined plates or louvres in such a manner that the sulphurous
acid in passing from the lower box to the upper box and from the latter to the
outlet is caused to pass through the grain which descends through the grain box,
substantially as described.
4. The combination with apparatus of the kind described of a horner or polisher,
grader, or fan, or all of these through which the grain is caused to pass after
leaving the grain box, substantially as described.
5. The improved apparatus for bleaching and dressing grain bereinbefore
described and illustrated in the accompanying drawing.
Dated this 29th day of June 1896.
G. F. REDFERN & Co.,
+, South Street, Finsbury, London, Agents for the Applicant.