IMPROVEMENTS IN FILTERS FOR THE DECOLORIZATION OF SHOAD IN SOLUTION AND OTHER LIQUIDS" SUGAR IN SOLUTION AND OTHER LIQUIDS " PROVISIONAL SPECIFICATION
Year: 1875

page_text: LETTERS PATENT to Richard Gervase Elwes, of 7, Westminsteı
Chambers, in the City of Westminster, Civil Engineer, for the
Invention of "IMPROVEMENTS IN FILTERS FOR THE DECOLORIZATION OF
SHOAD IN SOLUTION AND OTHER LIQUIDS"
SUGAR IN SOLUTION AND OTHER LIQUIDS
"
PROVISIONAL SPECIFICATION left by the said Richard Gervase Elwes
at the Office of the Commissioners of Patents, with his Petition, on
the 15th June 1875.
I, RICHARD GERVASE ELWES, of 7, Westminster Chambers, in the
City of Westminster, Civil Engineer, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN FILTERS FOR THE DECOLORIZATION OF
SUGAR IN SOLUTION AND OTHER LIQUIDS," to be as follows:-
My Invention relates to filters in which animal charcoal is employed,
and has for its object the construction and arrangement of filtering
apparatus in such a manner as to combine the process of upward
filtration with the means of from time to time admitting fresh charcoal
at or near the point of egress, and removing spent or exhausted charcoal
-

page_text: at or near the point of ingress. For this purpose the apparatus is
arranged so that the sugar in solution or other liquid to be filtered and
decolorized may be admitted through an entering pipe at the bottom
under a head or liquid pressure sufficient to force the liquid up through
the charcoal and out through apertures provided at the upper part of
the apparatus into a collecting chamber, whence it will pass off through
an outlet pipe, the fresh charcoal being admitted through a hopper fixed
at the top of the apparatus.
The vessel containing the charcoal is vertical, and may be of
cylindrical or other suitable form, and it has at the bottom one or more
-prolongations which terminate in one or more discharging chambers, a
valve being placed between each chamber and the filter to admit of
their communication being opened and closed, as required. There is
also at the bottom of each discharging chamber a valve, door, or cover
opening out into the air, through which the spent or exhausted and
fouled charcoal can pass into any convenient receptacle, and be removed
for cleansing and revivifying, as required.
The filtering vessel is furnished with an enlarged chamber at the
upper part, which serves as the collecting chamber for the filtered
liquid after it has ascended through the charcoal, the part of the vessel
through which the said liquid passes into the said chamber being pro-
vided with apertures covered internally with wire gauze or other suitable
material in order to allow the filtered liquid to pass out of the filter into
the collecting chamber without the charcoal (admitted from the hopper)
falling into the latter.
The liquid is or may be introduced into the filter through one or more
hollow cones fixed at or near the bottom, such hollow cones being
perforated at the bottom. By this means the charcoal may be prevented
from blocking up the entrance apertures, and it may be caused to pass
evenly down into the discharging chamber.
By the arrangement of filtering apparatus above described the process
of filtering is or may be continuous instead of, intermittent as usual;
also the portion of charcoal discharged from the discharging chamber
can be washed and revivified as fast as it is removed from the filter;.
also the full useful effect will be obtained from the. whole of the
charcoal employed before it is revivified; and, lastly, the whole of the
liquid filtered can be as completely decolorized as the portion first

page_text: passed through the filter, because the liquid in its descent to the collecting
chamber must pass through fresh charcoal before it issues from the
filtering vessel.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Richard Gervase Elwes in the Great Scal Patent
Office on the 14th December 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RICHARD
GERVASE ELWES, of 7, Westminster Chambers, in the City of West-
minster, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent bearing date the Fifteenth day of June, in the year
of our Lord One thousand eight hundred and seventy-five, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Richard Gervase Elwes, Her
special licence that I, the said Richard Gervase Elwes, my executors,
administrators, and assigns, or such others as I, the said Richard
Gervase Elwes, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN FILTERS FOR THE DECOLORIZATION OF SUGAR
IN SOLUTION AND OTHER LIQUIDS," upon the condition (amongst others) that
I, the said Richard Gervase Elwes, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands
and scals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed,
and cause, the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Richard Gervase Elwes, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the Drawings

page_text: hereunto annexed, and to the letters and figures marked thercon (that
is to say):
My Invention of "Improvements in Filters for the Decolorization of
Sugar in Solution and other Liquids," relates to filters in which animal
or other charcoal or other filtering material in powder or granules is
employed, and has for its object the construction and arrangement of
filtering apparatus in such a manner as to combine the process of upward
filtration with the means of admitting continuously or from time to time
fresh charcoal or filtering material at or near the point of egress of the
filtered liquid, and removing spent or exhausted charcoal or filtering
material at or near the point of ingress. The apparatus is so constructed
that by the employment of upward filtration the most exhausted portion
of charcoal or filtering material, that is to say, the portion which is nearest
to the point where the liquid to be filtered enters may be continuously or
from time to time removed, and fresh charcoal or filtering material may be
added at the part of the apparatus where the liquid escapes, so that the
liquid may always be brought in contact with fresh charcoal or filtering
material before it leaves the filter. For this purpose the apparatus is
· arranged so that the sugar in solution or other liquid to be filtered and
decolorized may be admitted through an entering pipe at the bottom
under a head or liquid pressure sufficient to force the liquid up through
the charcoal, and out through apertures provided at the upper part of
the apparatus into a collecting chamber, whence it will pass off through
an outlet pipe, the fresh charcoal or filtering material being admitted
through a hopper fixed at the top of the apparatus.
The vessel containing the charcoal or filtering material is vertical, and
may be of cylindrical or other suitable form, and it has at the bottom one
or more prolongations which terminate in one or more discharging
chambers, a valve being placed between each chamber and the filter to
admit of their communication being opened and closed, as required. There
is also at the bottom of cach discharging chamber a valve, door, or cover,
opening out into the air, through which the spent or exhausted and
fouled charcoal or filtering material can pass into any convenient recep-
tacle, and be removed for cleansing and revivifying, as required.
The filtering vessel is furnished with an enlarged chamber at the
upper part which serves as the collecting chamber for the filtered liquid
after it has ascended through the charcoal or filtering material, the part
..

page_text: of the vessel through which the said liquid passes into the said chamber
being provided with apertures covered internally with wire gauze or
other suitable material in order to allow the filtered liquid, to pass out of
the filter into the collecting chamber without the charcoal or filtering
material (admitted from the hopper) falling into the latter.
The liquid may be introduced into the filter through one or more
hollow cones fixed at or near the bottom, such hollow cones being per-
forated at the bottom. By this means the charcoal or filtering material
may be prevented from blocking up the entrance apertures, and it may
be caused to pass evenly down into the discharging chamber; but I
prefer to introduce the liquid into the filter through a perforated pipe,
as herein-after described.
By the arrangement of filtering apparatus above described the process
of filtering can be carried on with the advantages herein-after mentioned.
Having thus stated the nature of the said Invention, I will proceed to
describe more particularly in what manner the same is to be performed
by the aid of the accompanying Drawings, in which is represented the
to Fig. 1) showing the top and bottom of the apparatus, the intermediate
part consisting of a cylinder between them so as to form a continuous
apparatus throughout its entire length.
A is a vertical vessel of cylindrical or other convenient sectional form
having below it one or more conical or tapered prolongations B leading
to one or more discharging chambers C, which may be of any convenient
sectional form. At the upper end of the discharging chamber C is a
door or valve D, and at the lower end of the same is a second door or
valve or cover E. By means of the upper valve Da communication
can be opened from the vessel A into the discharging chamber C, and
the lower valve or door E opens from the discharging chamber C into
the air. F is an air cock fitted at the upper part of the discharging
chamber for the admission and escape of air, as may be required; G is
an inlet pipe fitted to the same for the admission of warm water to wash
the exhausted charcoal, as required. At the bottom of this chamber is
a flexible exit pipe T communicating with other pipes leading re-

page_text: spectively to a syrup or juice tank, a sweet water tank, and an outlet
for waste water, and indicated by the three arrows H, I, K. The
entrance to the pipe T is protected by wire gauze and filter cloth or
other suitable means to prevent the charcoal from passing into it. The
filtering vessel A is fitted at the upper part with an enlarged portion L,
in which the filtered liquid may collect and be drawn off by an exit
pipe M. The filtering vessel is also fitted with an inlet pipe N for water
with which to wash the whole contents of the filter when desired.
O is a hopper at the top of the apparatus through which the fresh
charcoal is introduced, as required. The lower end of this hopper is
continuous with the sides of the filtering vessel A, in which are formed
apertures P within the enlarged portion L, such apertures being covered
with wire gauze, and one or more thicknesses of filter cloth through.
which the filtered liquid can pass out into the enlarged portion L
without any charcoal or dust passing out with it. This part of the
apparatus is represented in section on an enlarged scale at Fig. 3.
The liquid to be filtered is introduced at the lower part of the
apparatus by means of a pipe Q terminating in a perforated pipe which
runs round the inside of the filtering vessel, but any convenient form of
inlet pipe may be used. The pipe Q leads from a tank placed above the
level of the point where the filtered liquid leaves the filtering vessel,
so as to obtain the pressure or head required to force the liquid up
through the charcoal.
At Fig. 4 is shewn in vertical section, and at Fig. 5 in plan on an
enlarged scale the valve or door E, which is adapted to open by turning
on a pivot at E*, being moved thereon as required by means of a
handle R, and fixed by set screws S, S.
The method of working the apparatus is as follows:-On the valve D
at the top of the discharging chamber C being closed the filtering
vessel A is filled with charcoal through the hopper O, and the liquid to
be filtered is admitted by the entering pipe Q at the bottom of the
charcoal and out through the apertures P, P, into the enlarged portion
or collecting chamber L, whence it will flow away by the pipe M. As
soon as the liquid ceases to run quite colorless the entry pipe Q is
closed, also the valve or door E at the bottom of the discharging
chamber C. The valve D at the top of this chamber is now opened, and
the lowest portion of charcoal, which will be the foulost and most

page_text: exhausted is allowed to fall into the discharging chamber C. As soon
as the discharging chamber is full the valve D is closed, the inlet pipe Q
is re-opened, and the filtering process is resumed. In the meantime a
fresh supply of charcoal has been introduced from the hopper O into the
top of the filtering vessel A, falling downwards by gravity as the whole
column of charcoal descends, when the valve D is opened; the escaping
liquid now comes in contact with this fresh charcoal, and is completely
decolorized as before.
The exhausted charcoal removed from the filter contains a quantity of
adhering liquid, which may be drained off from it while in the dis-
charging chamber by the pipe T, and pumped up again to the tank,
whence the filtering vessel is supplied.
In the case of sugar the syrup or juice is first drained off by a pipo
(indicated by the arrow H) leading to the syrup or juice tank; the
charcoal is then washed with warm water admitted through the pipe G,
the resulting sweet water being led away to the sweet water tank by the
pipe indicated by the arrow I. When all the syrup has been extracted
the charcoal may be further washed if desired, the foul water being led
away to waste by the pipe indicated by the arrow K. The charcoal or
other filtering material is finally removed from the discharging chamber
by opening the valve or door E at the bottom of this chamber, and
taken to be burnt or revivified in the usual manner when required.
On a cessation of operations the whole contents of the filter can be
drained of syrup or juice, and washed by means of the pipes connected
witli the filtering vessel and discharging chamber.
The advantages resulting from the foregoing process are as follows:-
First. The filtering operation is continuous, or nearly so, whereby a
smaller number of filters is required, and the process can be carried on
day and night if desired.
Secondly. There is a saving in the quantity of charcoal or filtering
material required to be kept on hand at one time.
Thirdly. The full useful effect can be got out of each portion of
charcoal before it is reburnt, whereas under existing systems much of
the charcoal when removed from the filters is only partially exhausted.
In this manner a saving is effected in the cost and waste of reburning.

page_text: And, Lastly. The whole of the liquid filtered can be as completely
decolorized as the first portion, whereas under existing systems of inter-
mittent filtration the last portion of liquid passed through the filter
leaves it in a more highly colored state than the first portion.
Having thus described the nature of the said Invention, and in what
manner the same is to be performed, I would remark that the particular
-form of apparatus herein-before described, either for removing the
exhausted charcoal or filtering material, or for supplying fresh charcoal
may be varied; but I hereby declare that what I claim as of my
Invention is,―
[
First. The construction of filters, in which upward filtration under
liquid pressure is combined with the means described, or other suitable
means, for removing the exhausted charcoal (or other filtering material)
from the bottom of the filter where the liquid enters, and also with the
mcans described, or other suitable means, for supplying fresh charcoal
at the top of the filter where the filtered liquid escapes, by which the
process of filtration and decolorization is rendered continuous and
complete, as described.
And, Secondly. The apparatus in its combined form, as and for the
purpose herein-before described.
In witness whereof, I, the said Richard Gervase Elwes, have here-
unto set my hand and seal, the Thirteenth day of December, in
the year of our Lord One thousand eight hundred and seventy-
K. GERADE BY.
Witness,
CHARLES STANLEY CHAMPION CRESPIGNY,
Secretary,
Crown Slate Co., Limited,
20, St. James' Square,
Notting Hill, W.,
London.