AN IMPROVED SYSTEM OR PROCESS OF TREATING ANIMAL CHARCOAL USED IN THE PURIFICATION OF SUGAR, AND ALSO PROVISIONAL SPECIFICATION
Year: 1866

page_text: LETTERS PATENT to George Gordon, of San Francisco, California, at
present residing at Morley's Hotel, Charing Cross, in the County of
Middlesex, for the Invention of "AN IMPROVED SYSTEM OR PROCESS OF
TREATING ANIMAL CHARCOAL USED IN THE PURIFICATION OF SUGAR, AND ALSO
PROVISIONAL SPECIFICATION left by the said George Gordon at the
Office of the Commissioners of Patents, with his Petition, on the 6th
October 1866.
I, GEORGE GORDON, of San Francisco, California, at present residing at
Morley's Hotel, Charing Cross, in the County of Middlesex, do hereby
declare the nature of the said Invention for "AN IMPROVED SYSTEM OR
PROCESS OF TREATING ANIMAL CHARCOAL USED IN THE PURIFICATION OF SUGAR,
AND ALSO IMPROVED APPARATUS TO BE EMPLOYED IN SUCH PROCESS," to be as
follows:-
In the ordinary method of treating animal charcoal by sugar refiners the
"char" (as it is termed) after it has been used for filtering sugar liquid is
placed in cisterns or tanks, and simply washed by merely running an abundant
supply of water through the mass; it is then removed from the cistern or

page_text: tank by taking off a man-hole plate or trap near the bottom of the cistern and
raking it out into trucks or wheelbarrows, in which it is conveyed to the
heads of the re-burning kilns, where it is re-burned in upright pipes surrounding
or passing through the furnace of the kiln; it then descends through con-
tinuations of the said pipes (called "coolers"), passing under the kiln and
exposed to the open air, where the red heat gradually dies out, and about
every half hour or so the operator draws out from the bottom of the coolers
about as much "char" as will allow the column to descend in the pipes
(say) twelve inches, and another man fills in more wet "char" at the
top, cach quantity of "char" occupying usually about six or seven hours
to travel down; it is then removed in the bottom wheelbarrows, and
after having been spread on a floor to cool is hoisted to the cistern tops
for use. The action of the ordinary kiln is exceedingly imperfect, and the
wet "char" is put in at the top in a solid compacted state, and of course
requires drying before it can be burned; then in order to allow the "char" to
descend in this state it is necessary that the pipes should be of considerablo
diameter, and they are usually made of an oval section about eight inches by
four inches. The mass can only be burned by the conduction of red heat
from the hot iron sides of the pipes from particle to particle of the "char" to
the centre, and as it is well known that charcoal is almost a non-conductor of
heat it will be evident that this process is slow, and the outer portions of the
"char" next the pipes is almost certain to get overburned before the central
portion gets burned at all. This overburning of the charcoal is very detri-
mental thereto, and if carried to a great extent completely destroys it and
fresh "char" is required; such is the present mode of re-burning charcoal.
The washing, which is almost as important, is merely effected by running water
into a cistern full (say from ten to twenty feet deep) of "char," and there is
no intermediate process of drying between the washing and burning.
My improved system is as follows:-Beginning with the "char" as it
comes out of the cisterns, I receive it upon a carrier belt made with a simple
graduating apparatus, which removes a stated and equal quantity cach second
or minute and acts continuously; this graduating apparatus governs the
whole subsequent process. The operator calculates how much "char" per
minute will give him the total amount required by him in the twenty-four
hours, and sets his gauge accordingly. This graduating apparatus may be
described as follows:-At the foot of a "char" cistern, opposite the man-hold
whence issues the "char" to be treated, and over the common carrie
belt which conveys it to the washing cylinder, is a movable table
or platform of, say, four feet square. This table has affixed to it two bel

page_text: drums of six to twelve inches diameter, one at each end, so placed that a
belt placed over them will traverse upon the table, sliding on it or upon rollers
let into it, and return under the table. This belt, which is, say, from six to
twenty inches wide, has placed across it at distances of from three inches to
nine inches angle irons, one face of which is rivetted to the belt, and the other
face is vertical to the belt. The operator rakes the "char" out of the cistern
on this graduating table, and it falls in a heap, covering table and belt; as
the belt traverses the angle irons carry off before them from the heap of
"char" as much as the depth of the vertical angle will catch. It is carried
off the table over the drum, and it falls on to the common carrier belt below
the table. The graduation of the quantity of "char" thus removed is effected
either by widening the belt or heightening the vertical angle of the cross anglo
irons, or increasing the speed of the belt itself; for example, a belt eight
inches wide with angle irons of one inch deep will carry off eight cubic inches
of "char" for each lineal inch of belt, and if this belt travels eighteen fect
per minute it will carry off one cubic foot of "char" per minute, or increase
the speed to twenty-seven feet per minute or heighten the vertical side of the
angle iron to one and a half inches, and the belt will carry off one and a half
cubic feet of "char" per minute, and so on. The carrier belt conveys the
"char" cither to, firstly, a rotating washing and boiling machine, where it is
washed by cold water or boiled in hot water in such a way as that the "char"
shall be kept in constant motion, passing continuously through the water, and
that at the same time the scum and "fluff" disengaged from the "char" by
the water, and the motion shall flow off constantly; second, to a rotary drying
machine (hereafter described), where the "char" thus washed or boiled is
continuously received in the same even stream from the carrier belt and dried;
or if the operator determines that his "char" does not want washing or boiling,
but merely drying and re-burning he turns the carrier belt (which is movable)
direct to the drying machine, and dispenses with the washing and boiling
operation at his discretion. The drying machine consists of a horizontal
cylinder (open at both ends), say about four feet diameter by thirty feet
long; a fire is placed under one end where the wet "char" enters the
cylinder, and the heat therefrom travels slowly under the cylinder to the other
end (the cylinder slowly rotating), and passes back through a smoke pipe
through the inside of the cylinder in the midst of the "char," and out through
a chimney at the front end above the fire; the internal cylinder or smoke
pipe rotates with the external cylinder. The inside of the external cylinder
and the outside of the internal one (or smoke pipe) are provided with longi-
tudinal flat bars set on edge, and slightly screwed or diagonal in their position,

page_text: so that as the cylinders rotate the "char" is lifted, spread, and thrown over,
and slowly worked towards the other end of the cylinders, where it falls on to a
similar carrier belt (also movable), which conveys it at the will of the
operator, firstly, direct to the re-burning kiln, or, secondly, to the vacuum
chamber, and thence to the kiln. If the "char" is "lime foul," and it is
desired to remove this lime, it passes first to the vacuum chamber, which
chamber together with the treatment of the "char" therein forms a very
essential feature of my Invention. This vacuum chamber is fitted with a
vertical central pipe which communicates with a vacuum pump, and is perforated
with small holes and enclosed with fine wire gauze to prevent the char
from passing through, and also with a series of annular perforated pipes
surrounding the former and communicating with a main or mains, outside
which is (or are) fitted with cocks to inject hot water, cold water, steam, acid
and water, or acid gas. The operator having filled the chamber with "char"
exhausts the air thoroughly, thus extracting the air from every pore of cach
particle and rendering the interior structure of the" char" instantly accessible to
the acid and water or acid gas, which converts the insoluble lime into the soluble
chloride of calcium, in which state the subsequent washing readily removes it;
it also converts the iron in the "char" into a soluble and removable condition.
The operator having obtained a good vacuum allows his acid bath or gas to
rush in, and then pauses awhile till the liquor is neutral, when he proceeds to
wash it out by alternately exhausting with the air pump (which removes the
water also) and then flushing with pure water or steam at pleasure. This
alternate exhausting and flushing is a marked feature of my Invention, for
by exhausting alone the "char" would become compacted and solidified, so
that it could not be washed by merely drawing water through from the top,
but by flushing water through the internal perforated pipes (when a vacuum
has been created) the mass is heaved and disintegrated and all its particles
separated and thoroughly washed; this alternate exhausting and flushing is
continued till the washing waters show neither acid nor chloride of calcium
by chemical test; the "char" is then drained by a final action of the pump
and the hot-air cock opened, and hot air is thus drawn or forced through the
mass till it is quite dry. In this condition it is generally fit for use, but if
the operator considers that it requires re-burning the carrier belts then convey
it to the kilns hereafter described.
The re-burning kiln I construct as follows:-Instead of having pipes of four
to eight inches in diameter, I pass the "char" (which having been previously
dried as above described runs like dry sand in an hour glass) through pipes
from half to three-quarters of an inch in diameter, so that it becomes

page_text: thoroughly red hot through in a few minutes; the carrier belts convey it to
the top of the kiln by means of simple separators, or division plates convey to
each pipe its proper quantity and no more.
quantity and no more. The "char" passes through
these small pipes in the kiln chamber (which is kept at a red heat) and
through the bottom into coolers hercafter described, which are attached to the
bottom of the pipes. Ordinarily the "char" is cooled in thin sheet-iron
pipes simply exposed to the action of the air outside, but this process is very
slow and also wastes the heat. I use the coolers of the same kind so as to
avail myself of the external atmosphere, but in addition thereto I interpose a
worm or a flat chamber filled with water inside the cooler, so that the "char"
passes all round the water, which rapidly extracts the heat, a constant stream
of cold water enters the worm or flat chamber and issues forth boiling, and is
conveyed away to wash the "s char" in some of the previous processes.
Small taps are arranged at the bottom of the coolers and set just wide enough
open to permit the "char" to issue therefrom as fast as it is fed by the belts
at the top; it falls finally on to a carrier belt, which conveys the "char" thus
treated back to the original cisterns whence it came, and it there falls through
a simple distributing apparatus, which spreads it evenly as it falls in the
cisterns ready for use. At the waste pipe of the charcoal cisterns I place a
sugar trap, which permits any liquid of only the specific gravity or density of
water to pass freely, but when any liquid of a greater gravity or density than
water presents itself the trap closes and stops the passing off of such liquid,
and thus prevents the waste of sugar liquid sometimes occasioned by tho
inattention of the operator.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Gordon in the Great Seal Patent Office on the
6th April 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
GORDON, of San Francisco, California, at present residing at Morley's Hotel,
Charing Cross, in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of October, in the year of our Lord One
thousand eight hundred and sixty-six, in the thirtieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said George Gordon, Her special licence, that I, the said George Gordon,
my executors, administrators, and assigns, or such others as I, the said
George Gordon, my executors, administrators, and assigns, should at any

page_text: time agree with, and no others, from time to time and at all times there-
after 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 "AN
IMPROVED SYSTEM OR PROCESS OF TREATING ANIMAL CHARCOAL USED IN THE
PURIFICATION OF SUGAR, AND ALSO IMPROVED APPARATUS TO BE EMPLOYED IN
SUCH PROCESS," upon the condition (amongst others) that I, the said Georgo
Gordon, my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, 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 George Gordon, do hereby declare the
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 in writing, and on reference to the accompanying Sheet of
Drawings, that is to say:-
Heretofore in the revivification of animal charcoal which has been used
in the purification of sugar the common practise has been to wash it
with water in the same tanks or cisterns (commonly called charcoal filters)
in which it had been placed for the purpose of receiving sugar liquors for
filtration by running water on to the head of the said tanks or cisterns when
full of charcoal, which water by percolating through the mass and out at the
bottom was supposed to perform the needful washing. For the further
purifying or reviving of charcoal it has been customary to convey the same
in trucks (after the washing process above described) to kilns or chambers
licated by furnaces, in which are placed cither upright pipes or rotating
cylinders, into which while yet wet the "char" (as is termed) is made to
descend, and in which it is first dried and subsequently burned or calcined.
When upright pipes are used in such kilns those pipes have been necessarily
of considerable size (generally of 5 to 6 inches in diameter if round, or
3 to 4 by 8 to 9 inches if oblong), so that the charcoal while yet wet and
not in a condition to run through small apertures may not stick in the pipes.
The consequence of using such a size of pipe is that the red heat from the
sides before it can reach the centre of the mass of char to make it red
hot is compelled to travel through from 1% to 3 inches of charcoal forming
the exterior portions of the mass, and owing to charcoal being a bad
conductor and transmitting heat slowly, such exterior portions are overburned

page_text: before the interior is burned at all. This overburning of the "char" is very
detrimental thereto, and if carried to a great extent completely destroys it,
and fresh "char" is required. When rotary cylinders are used in charcoal
kilus they are made red hot, and as they rotate the coarser or heavier portions
of the char roll constantly forward in advance of the mass on to the red hot
surface, and as more or less atmospheric air enters with the charcoal such
exposed portions become decarbonized and spoiled. Subsequently to such
re-burning the charcoal is made to descend while yet red hot into narrow
sheet-iron chambers called coolers, where it is cooled by the exterior air
impinging on their outer surfaces, after which it is drawn off at the bottom
by hand.
According to my improved system of treatment I receive the charcoal
from the charcoal cisterns or filters on to a graduating apparatus, which
causes an equal quantity to be delivered moment by moment (sufficient to
remove the entire daily quantity in 24 hours) on to a carrier belt, which conveys
it in the same even quantity to a washer and boiler, in which it is rotated and
boiled in 2, 3, or more successive waters, so that the char first is received
into dirty or previously used water, next into cleaner water, and lastly into
clean water, and all the while is rotated and thrown about in contact with
the boiling waters, while the fluff and impure matters disengaged by the
movement and the ebullition are made to float off as they rise to the surface.
The waters are kept boiling by heat applied externally to the cylinder and
by steam injected into the water. A feeding motion so constructed as that the
operator can feed fast or slow, and backwards or forwards, works the charcoal
through the washer (still in the same even quantity), out at the end opposite
to that in which it entered, where it cither falls in a heap to drain previously
to entering the drying cylinders, or is received into a centrifugal sieve in
which the drainable moisture is expelled by centrifugal force. From either
the heap or the sieve the char is conveyed by carrier belts (in the same
stream or even quantity which was first started from the char cisterns) into
a rotary cylinder or cylinders for the purpose of drying it. These rotary
cylinders revolve over a fire, the heat of which is conducted first under and
then over them (or is conducted first under them and then through them by
means of an internal cylinder for conveying heat and smoke). In the cylinders
are longitudinal ribs projecting from the sides and set at an angle of from
thirty to sixty degrees to a line drawn across the axis of the cylinder, which
carry up the char and throw it down in showers. The vapours disengaged
from the char by the heat of the cylinders are carried off by means of a
current of air which enters the cylinder at the end from which the dry char

page_text: issues, and escapes into a flue from the end at which the wet char enters.
There is an apparatus in the cylinders to feed the char forwards or back-
wards. These drying cylinders are not brought to a heat sufficient to burn
the char, but are strictly driers only. From the drying cylinders the char falls
on to an elevator belt, and is lifted to a point above the top of a re-burning
kiln, from which point it falls on to sheet-iron shoots which guide it, at the
will of the operator, either, to the re-burning kiln or to vacuum chambers
placed near the kiln. If at this stage it is found that the char contains
any substance which an acid or an alkali will render soluble so as to be
capable of being washed out, but which the action of fire would only burn
in, the charcoal is shot into cast-iron vessels, which I term vacuum cham-
bers, wherein (by an air pump) the air may be exhausted from its pores
previously to the admission of acids or alkalies either in a dilute liquid
or in a gaseous form; this vacuum chamber is fitted with a vertical central
pipe which communicates with a vacuum pump, and is perforated with
small holes and enclosed with fine wire gauze to prevent the "char" from
passing through, and also with a series of annular perforated pipes surrounding
the former and communicating with a main or mains, outside which is (or
are) fitted with cocks to receive hot water, cold water, steam, acid or alkali and
water, gaseous acid, or hot air, any of which pass into the mass of the charcoal
through the perforated annular pipes, and are drawn off through the central
pipe, which communicates with the vacuum pump. The operator having
filled the chamber with "char" exhaust the air thoroughly, thus extracting
the air from every pore of each particle and rendering the interior structure
of the "char" instantly accessible to the acid or alkali and water, or acid gas,
which converts the insoluble alkaline or acid matters into soluble salts, in
which state the subsequent washing readily removes them. In this chamber
atter the air is exhausted by the action of the air pump the liquids or gases with
which the charcoal is to be saturated are admitted and rush into the pores of the
charcoal instead of mainly attacking the external surfaces of its particles.
Washing is performed in this chamber by the alternate flushing with water or
water and steam and exhausting by the air pump. Hot air may also be
drawn in through the annular pipes aforesaid to dry the char, but the best
method of cleansing and drying the char after its acid or alkaline bath is to
return it to the washing cylinder and thence through the centrifugal sieve and
the drying cylinders to the re-burning kiln. The char after being thus washed
and dried (and if needed impregnated with acid or alkali when in vacuo, and
subsequently washed and dried) is next burned or carbonized without contact
with air in a kiln fitted with upright pipes or retorts; in order that no part of it

page_text: may be exposed to a red heat longer than is necessary it is made to descend
through very narrow pipes made of iron (or preferably of fire-clay), both sides of
which are kept constantly red hot; the width of pipe which I prefer is three-
fourths of an inch, which leaves only three-eighths of an inch thickness of
char to be heated from each side. The char would not descend through such
narrow pipes unless it had been previously dried, but when dry it precolates
through a small space like sand in an hour glass. In a few minutes (from 8 to 15
minutes) it becomes thoroughly and equally red, and while becoming red in
that time is made to descend through the red-hot part of the pipes into the
coolers, which are wider, sheet-iron continuations of the said pipes extending
through the bottom of the kiln. The char has to be cooled as expeditiously
as it is burned, to effect which a water chamber of sheet or cast iron (or of
iron pipes) is placed in the cooler, and cold water is admitted at the bottom
and comes out at the top of the chamber, having in its passage cooled the
char and become itself boiling hot or nearly so, in which condition it is con-
veyed away to the washer and boiler to assist in washing and boiling the char
in the preliminary process. At the bottom of the cooler are valves which
open by machinery for a few seconds every minute or two, and permit a small
quantity to descend out of the coolers on to a carrying belt running under
them, which conveys it either direct or by means of other carrying belts to
the char cisterns from which it was at first taken. The covering or roof of
this re-burning kiln, when clay pipes are used, is supported entirely on the
clay pipes, so that as they shrink by use the covering may shrink with them.
Each upright pipe where it comes through the top of the kiln is fitted with
an iron hopper from 15 to 24 inches high, round the outer sides of which the
air circulates and checks the ascension of red heat to the part where the char
lies exposed to the air. The joints between the hopper and the fire-clay
retort, as well as between the roof of the kiln and its exterior walls, are made
air-tight by a stratum of ashes or other non-combustible finely divided
substance laid upon them.
Such being the nature and object of my said invention for an improved
system or process of treating animal charcoal used in the purification of
sugar, I will now proceed to describe the apparatus by means of which (or
by modifications of which) the said process is carried into practical effect, and
in order that the same may be distinctly understood I have annexed hereunto
three Sheets of Drawings illustrative thereof, and have marked the same
respectively with figures and letters of reference corresponding with those in
the following explanation thereof, that is to say :-
Sheet 1 of the annexed Drawings (which is drawn to a scale of about

page_text: 3-fourths of an inch to a foot) illustrates the first part of the apparatus,
consisting of the washing and boiling cylinder, a centrifugal sieve for draining
the "char" on its passage from the washing and boiling process, and a pair
of drying cylinders.
Figure A represents a longitudinal section through the washing and boiling
cylinder and one of the drying cylinders, together with an exterior end view
of the centrifugal sieve. In this view the upper part of the longitudinal
section is taken through the line A-B, in Figures B and C, and the lower part
through the line C-D, in the same Figures. Figure B represents an
elevation of the driving end of the apparatus; Figure C is an elevation of the
reverse end of the apparatus, the centrifugal sieve being shewn in section,
Figure D being a half end clevation complete, and Figure E a vertical
transverse section of the three cylinders, the left-hand portion being taken
through the line E-F, on Figure A, and the right-hand portion through the
line G-H.
"3.
(1) is a "char" washing and boiling cylinder or vessel of a hexagonal form
placed with its axis horizontal and divided into three compartments A¹², A³, A³,
having 6 large plates B' running longitudinally through cach compartment.
On the plates are upright ribs C¹ set at an angle, as shewn in longitudinal
section Figure A. Between the plates and on the sides of the cylinder aro
short ribs D¹, see Figure E; these ribs being placed so as to throw the char
from the feed end towards the exit end. 'E', E, E³, E, are 4 flanges
dividing the water space into 3 compartments, E¹ being the highest, E² being
three-eighths of an inch lower, E³ being "lower than E and E* being ³/
lower than Es; these flanges are reduced in height from E' to E', so that the
water may flow over cach successively until it exits at E. F is a feed
roller and belt on which the char enters. G', G', is an adjustable feed
consisting of a series of flat plates hung on centre spindles between 2 stationary
iron side plates G, G. The flat plates are connected at the bottom edge by
a rod G³, by which the workman sets the plates at any angle, so that the char
falling upon them from the plates B' when the cylinder rotates may shoot
forward or backward according to the time he may desire it to be detained in
the cylinder; this cylinder has a bell mouth H' for the exit of the char at
one end, and a bell mouth H2 for the exit of the water at the other; this
cylinder is driven by a chain I', and revolves on grooved rollers J' at one end
and flat surface rollers J2 at the other. The sheet-iron shoots K', K', at the
right-hand end of the cylinder receive the wet char as it issues from the
washing and boiling cylinder, and conduct it into the centrifugal sicve
honners L. L.

page_text: (2) is a centrifugal sieve consisting of an annular perforated ring divided
vertically through the centre by the plate M', and revolving on the shaft N';
this sieve is lined with punched or perforated copper plate or wire gauze ; it
is provided with hoppers L, L, which receive the wet char and retain it
while the previous charge is drying. The hoppers are open at the bottoms L³
to allow the contents to drop into the sieve; this centrifugal sieve is provided
with cutters or scrapers O', 0%, oscillating on a shaft Os against the char in the.
sieve when it requires to be removed. P', P³, are spouts down which the char
so removed falls into the hoppers Q', Q, which feed the drying cylinders (3), (4).
The centrifugal sieve is provided with a stationary-outer case Q to collect
the water driven off from the wet char, which is conducted away from the
said outer case by a waste pipe Q'. (3), (4), are drying cylinders made in
three parts for convenience of casting and handling; these are plain cylinders
externally, but internally ribs R', R', R', R', are cast therein, being set at
a suitable angle of from thirty to sixty degrees to a line drawn across
the centre. Through the centres of these cylinders is an adjustable feed S',
which is similar in all respects to the adjustable feed G', G, G³, described
with reference to the washing and boiling cylinder (1). The cylinders (3), (4),
are provided with feed hoppers Q', Q³, (Figure C), at the bottom of which are
belts Q, Q, revolving on rollers Q, Q, connected to the hoppers and
rollers Q' attached to the adjustable feed S', as shown in longitudinal section of
cylinder (3), and to a similar roller, not shown, in cylinder (4). T', Figuro A.,
is a discharge spout for the char when dry. The cylinders (3), (4), are pro-
vided with a straight cylindrical mouth-piece U', U'. On the cylindrical mouth-
piece U of the cylinder (3) is keyed a spur-toothed wheel U*, into which is
geared the driver pinion U³; the motion thus obtained on the cylinder (3) is
transmitted to the cylinders (1) and (4) by an endless chain U (Figure B)
working in chain grooves from the pulley U³ on the cylinder (3) to U* and I¹
on the other cylinders. The cylinders (3) and (4) revolve on grooved rollers
at the discharge end and on plain rollers at the feed end. The vapour created
in the process of drying is removed by a pipe in each cylinder (3), (4), placed
over the feed roller at the feed end; this pipe, marked V₁, enters the flue, the
draught of which carries off the vapour. The exit ends of the cylinders (3),
(4), are partially closed by stationary plates W', W', fixed to the frame of the
adjustable feed S', the said plates having openings at the bottom to permit
the exit of the dry char; these three cylinders are set in brickwork, forming
three arches X, X, X. Fire is applied under the feed ends of both
cylinders (3), (4), as shown in the furnace Y, Y, the current of heat
traverses under the cylinders (3), (4), towards the discharge end from Y' to Y',

page_text: where it ascends to the upper half of these cylinders to Y', where it rises into
the chamber of the washing and boiling cylinder, traversing it to Ys, and
heating it, and finally issuing out at the common flue Y'. The ends of the
brickwork are closed in by cast-iron plates Z', to which the carrier rollers are
attached, and which are secured by long bolts Z running through tubes
bedded in the brickwork, and fastening both end plates solidly together.
From the drying cylinders above described the "char" proceeds either to the
vacuum chamber or to the re-burning kiln.
Sheet 2 in the annexed Drawings shows the re-burning kiln with its cooling
apparatus (drawn to a scale of about three-fourths of an inch to a foot) and
the vacuum chamber (drawn to a scale of about half an inch to a foot).
Figure A is a sectional plan view of the kiln; Figure B is a sectional
elevation through the centre of the furnace on the line A-B, (Figure A);
Figure C shows on the left-hand balf an exterior elevation of the kiln; and
on the right-hand half a sectional elevation through the line C-D, (Figure A);
Figure D is a sectional elevation through the line E-F, (in the same Figure);
Figure E is a plan and section of one of the fire-bricks of which the retort
pipes are formed, drawn to a scale of one inch and a half to a foot; and
Figure F is a plan and sectional elevation of the vacuum chamber.
The retorts A', in Figures A, B, C, D, and E, are made of fire-clay, but
may be made of iron with vertical chambers three-fourths of an inch wide,
four inches long, in divisions or bricks about eight inches deep. The joining
surfaces are grooved and ridged as shown at A² in all the above Figures. The
topmost brick but one A³ (Figures C, D,) is made with greater exterior
dimensions than the rest, so as to fit snugly together between the retorts, as
shown in Figure D, and to the lining walls of the kiln as shown at B² in
Figures C, D, and to the roof-brick C¹ at Figure C. The topmost brick A*
is made to receive the cast-iron hoppers D' (Figures D, E,). The roof of the
kiln is formed by the hollow fire-bricks C³, which are supported on the retorts,
as shown in Figures B, C. The hollow brick is covered by some non-
conducting material shown at E, and by the hollow cast-iron plates E
(Figures B, C). There is a lining wall F¹ of fire-brick inside of the outer
wall of the kiln (Figures A, B, C, D); between the walls is a two-inch
space. The whole top of the kiln, except the covering of the outer walls, is
carried on the retort pipes and the lining wall F, so as to secure equality of
shrinkage. The furnace G¹ is covered with fire-tiles G* (see Figures B, C,)
which compel the heat to pass up between the retorts at the openings G³
(Figures B, C,) into the flue G, which traverses within the outer walls in
three sides of the kiln. The coolers of sheet iron hang under the kiln, as

page_text: shown at H' (Figures C, D,); inside the coolers is a water chamber H², fixed
at top and bottom. Cast-iron pieces H' and H', into which water pipes are
tapped, permit cold water to enter at the bottom and exit at the top, which.
water will be heated by cooling the char; this heated water is led away to the
washing cylinder (1) in plate 1. Instead of pipes this water chamber may
be made of plate iron. The bottoms of these coolers are furnished with slides,
which open or shut holes in the bottom casting through which the char makes
its exit; these slides being worked intermittently by engine power, and so
regulated as to retain the char in the pipes the required length of time
calculated for burning the char sufficiently.
Figure F is a vacuum chamber or acid bath tank, which consists of a plain
cylindrical vessel with an opening at the top J, J, through which the tank is
filled; J', J', are two doors at the bottom by which the char is taken out
again; K' is a vertical pipe in the centre of the tank, with a perforated part
K and a solid part K³ alternately, the perforated part being covered with
fine wire gauze. Inside of the pipe K' is another pipe L', for the purpose of
filling up the space inside when the acid is used. M' are annular pipes,
which are perforated with fine holes for distributing through the body of the
char an acid or alkaline bath, steam, water, or hot air; M² is a vertical pipe
through which the said substances pass to the annular pipes; N¹ is a branch
pipe to which the air pump is attached.
The general arrangement of the whole apparatus, and the method of
connecting the same by means of carrier belts, will be seen on reference to
Sheet 3 of the Drawings, which represents a portion of the char tank room of
a sugar refinery and a general plan of the structure containing the washing,
boiling, and drying cylinders and centrifugal draining sieve, the vacuum
chambers and the re-burning kiln and coolers, together with the belts which
connect the whole for carrying the "char" and the graduating apparatus for
first feeding the belt, all drawn to a scale of about a quarter of an inch to a
foot.
In this Sheet Figure A is a general plan view of the whole arrangement.
Figure B is a vertical section through the line A-B, in Figure A; Figure C
is a similar section through the line C-D, and Figure D is a similar section
through the line E-F; this arrangement is suitable for a refinery where the
"char" may require an acid bath frequently.
1, 1, are two sets of washing and drying cylinders; 2, 2, are two vacuum
chambers or acid bath tanks; 3, 3, is the re-burning kiln (the working of
these has been described with reference to Sheets 1 and 2); 4, 4, the walls of a
house containing the whole apparatus; 5, 5, the chimney for the flues from

page_text: both sets of washing and drying cylinders and the kiln; 6, 6, is a part of the
char cistern room of a refinery. The carrier belt arrangement is as follows:-
A is a belt passing through the cistern room, which is loaded by char
to a regular thickness by a regulator loading table to be hereafter described;
the char is carried forward and falls off the belt into the washing and boiling
cylinder; when the belt is passing over the roller to return the char is
passed through the washing and drying cylinders as described with reference
to Sheet 1, after which it is emptied into a box B¹, in the bottom of which
the belt A' travels round a roller. The char is carried by the belt A to the
box B, into which it falls while passing over the roller; at the bottom of the
box B is a roller over which a belt A' passes; the char is again carried by
the belt A until it again falls into the shoots B³ in passing over the roller at
the top, and falls into cither acid tank marked 2 or on to the belt marked A³,
which feeds the kiln 3. After the vacuum and the acid bath have been
applied, and the surplus acid having been pumped or drained off, the char is
taken out at the bottom and placed on the table B', in the bottom of which
is a regulating feed which loads the belt A', which latter carrics the char
until it falls upon the belt A5, while passing over the roller; the belt A now
carrics the char into the second set of washing and drying cylinders, where
the acids and salts of lime are washed out and the char again dried, when it falls
into a box B³ from which the char is carried by the belt A' up to a box B, which
is separated from B2 by a central division. At the bottom of the box B° the
belt A passes over a roller and carries the char up until it passes over the
roller and falls down a shoot on to the belt A; over this belt are two dividers
or scrapers B, B³, which cause the char to fall in equal quantities on each
side of the kiln; the char having passed through the kiln, as shown in
Plate 2, falls from the coolers on to belts A° under the kiln, which carry the
char and let it fall on to the belt A, which belt carries the char back to the
cistern room.
Figure E represents an adjustable feed table for loading a carrying belt to
a regular thickness of char.. C₁ is a hopper, having for its bottom the belt C²
moved by rollers C, C, which are driven by a rope pulley C'; this belt has
on its surface vertical cross bars, which catch the char and impel it forward
until it drops on the carrying belt A', shown in general plan. A slide C
in the end of the hopper above the belt may be raised at the will of the
operator, so as to permit more char to move forward with the belt than the
vertical cross bars actually catch; the feed may also be regulated by driving
the belt pulley O' faster or slower.
Having now described the nature and object of my said Invention for

page_text: "An Improved System or Process of Treating Animal Charcoal used in
the Purification of Sugar, and also Improved Apparatus to be employed in
such Process," together with the manner in which the same is to be or may
be performed or carried into practical effect, I wish to state that I do not
confine myself to the precise form, dimensions, or movements of the apparatus
described, as many deviations may be made therefrom which will still permit
my improved system or process of treating charcoal to be effected with
more or less success; but what I claim as original and constituting my
Invention is,-
Firstly. The automatic handling or conveying of the "char" in small and
constant quantities upon carrier belts from the char cisterns or from near the
entrance end of the washing cylinder through the various processes of purifica-
tion, which allows the effect of these processes to be exercised continually on
the smallest regular quantities at a time sufficient to treat the required daily
amount to be purified.
Secondly. The washing and boiling of the char in a rotating cylinder in
such manner as to cause it to pass through and be washed, boiled, and thrown
about in successive quantities of water, commencing with dirty or previously
used water and finishing with clean water, while the impurities disengaged
from the char wth float to the surface can flow off continuously at one
end, the washed char being discharged continuously at the opposite end and
without emptying away the main body of hot water being used.
Thirdly. The drying of the char in open rotating drying cylinders having
ribs or projecting plates on their inside surface at an angle of from 30 to
60 degrees to a line passing across their axes sloping upwards so as to
carry the char well round with the cylinders and shower it down as they
revolve, while currents of air previously heated or otherwise pass freely
through the cylinders from the end where the dry char issues to the end
where the wet char enters, and thence by a flue into the chimney to carry off
the vapours formed.
Fourthly. The feed motion in the washing and boiling and drying cylinders,
consisting of vanes or plates of iron hung on spindles between two
stationary side plates running through the cylinders, which vanes or hung
plates are connected with a rod or rods or chains either at the top or bottom
edge, which enables the operator outside either to keep them vertical or to
slope them to any angle backwards or forwards as he may desire to feed the
char.
Fifthly. The employment of a chamber to contain char whence the air can
be exhausted by means of an air pump from its pores, and the use of per-

page_text: forated pipes distributed through the body of the char in such chamber, by
some of which pipes purifying substances or hot air can be rapidly
disseminated, and by others of which the same substances can be rapidly drawn
off through the air pump.
Sixthly. I claim the system of drying the char either by open rotating
cylinders heretofore described or by drawing or forcing hot air through the
char in a chamber as heretofore described previously to re-burning, or so as to
dispense with subsequent re-burning.
Seventhly. I claim the method of re-burning char in a kiln substantially
as described, in which the char is received in hoppers on the top of the
kiln, round which the air circulates so as to prevent red heat ascending to
such portions of the char as are exposed to the open air, in which the char
descends through retorts or pipes in the heated chamber of the kiln of such
form and dimensions that no part of the char shall be more than three-
fourths of an inch from the red-hot exterior surfaces of the said pipes, and
lastly in which the char made thus red hot shall pass down into chambers
under the kiln, in the midst of or surrounding which are water chambers in
which a current of cold water enters, which while it cools the char is
itself heated for use in the washing or boiling cylinders or for other purposes,
thus expeditiously cooling the char and at the same time utilizing the heat.
Eighthly. I claim generally the improved system or process of treating
animal charcoal used in the purification of sugar, as herein-before described,
together with the general novel construction and arrangement of the apparatus
employed in such process, as herein-before described and represented in the
Drawings annexed, or any mere modification thereof constructed and operating
in substantially the same or a similar manner.
In witness whereof, I, the said George Gordon, have hereunto set my
hand and seal, this Third day of April, in the year of our Lord One
thousand eight hundred and sixty-seven.
Witness,
BRISTOW HUNT,
Solicitor and Patent Agent,
1, Serle Street, Lincoln's Inn.
GEORGE GORDON. (L.S.)