IMPROVEMENTS IN THE PREPARATION OF PEAT FOR FUEL, AND IN APPLIANCES OR APPARATUS FOR THE PURPOSE.
Year: 1874

page_text: LETTERS PATENT to Sir Francis Charles Knowles, Baronet, of Lovell's
Hill, in the County of Berks, for the Invention of "IMPROVEMENTS IN
THE PREPARATION OF PEAT FOR FUEL, AND IN APPLIANCES OR APPARATUS FOR
THE PURPOSE.
"
Sealed the 30th October 1874, and dated the 1st May 1874.
PROVISIONAL SPECIFICATION left by the said Sir Francis Charles
Knowles at the Office of the Commissioners of Patents, with his
Petition, on the 1st May 1874.
I, Sir FRANCIS CHARLES KNOWLES, Baronet, of Lovell's Hill, in the
County of Berks, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN THE PREPARATION OF PEAT FOR FUEL, AND IN APPLIANCES OR
APPARATUS FOR THE PURPOSE," to be as follows:-
The object of this Invention is the preparation and production of con-
densed peat in a form convenient for consumption by methods more.
economical than those hitherto in use, and at all seasons of the year,
excepting only during actual frost. I take the said peat from the bog
deposit thereof, either in the solid or in the pulpy state, and I cut up the
same within a vat armed with serrated Archimedean cutters in the form of

page_text: screw blades placed in pairs, one above the other, one being right
handed and one left handed, with their respective teeth opposed, each
successive pair deviating horizontally by a small angle from the position
of the pair immediately below it, as herein-after more exactly described.
In each pair of blades one is fixed in the vat or drum, the other revolves
upon an axis, so that every tooth of the lower one is successively opposed
to every tooth in the one above it. A small interval capable of simple
adjustment if need be is left between the rows of opposing teeth; except
in the highest and the lowest blade both edges of the blades are
serrated. The vat containing these blades or cutters may be of any
dimensions, depending on the motive power of the engine which drives
them. The vat itself (one or more, as the case may be) is open at the
top and at the bottom. It is placed vertically in a large cistern or tank
destined to receive the peat or peat pulp after laceration by the cutters
is completed.
A circulation of the raw material between the mass in the vat and the
upper opening of the vat is kept up by means of a set of dredging
buckets upon its endless chain, which continuously deliver the pulp
from below into the upper opening to be again passed through the
cutters..
When the peat is solid it must be macerated with water in the cutting
apparatus so as to reduce it to pulp. When it is completed the coaly
or pitchy parts of the peat are readily separable from the undecomposed
rushes or other vegetable matter, and they are in fact so separated by
appropriate sieves or strainers at the apertures below through which
the mixture flows out of the tank. From this the watery pulp is
conducted to the filters in the second stage of the process by means of
gutters, along which revolving Archimedean screw plates propel it, a
mode of propulsion well known and long in use.
The filtering apparatus consists of a strong iron chest capable of
sustaining a heavy pressure. It is furnished at the top with a ledge
on which is a bedding of caoutchouc. Upon this bedding rests a strong
iron plate full of small perforations. Above this again, surrounding it,
and flush each to each with the four sides of the chests, are boards
turning on hinges, and fitted at the angles of junction so as to form a
shallow water-tight compartment. The depth of this is such as to
admit one charge of peat pulp containing the quantity of solid matter
required for the bricks to be made after filtration of the water. Above

page_text: the perforations, when the apparatus is to be put in action, is placed a
cheap felt cloth, upon which the wet peat pulp is allowed to flow from
the tank or reservoir until the wooden compartment is filled. Con-
veniently connected with the filtering chest is an exhaust pipe, by
means of which through appropriate valves the air is pumped out by
the action of the engine until any required degree of pressure is exerted
upon the surface of the pulp. This pressure must be gradually
increased until all the water being filtered away the compression
solidifies the mass. The slab of compressed peat thus formed is now
to be carefully removed from the filter, and conveyed to the "brick
cutter." For this purpose it is carefully placed upon a low waggon
running upon small iron wheels adapted to a tramway or railway. At
the opposite sides of this waggon are firmly fixed two racks, which work
in two large pinions concentric with an iron or strong wooden cylinder.
This cylinder, revolving round a fixed axis, carries in the direction of its
rotation the waggon with its slab of peat, which runs with its wheels
upon the tram or railway, so that in the absence of any obstacle the
surface of the cylinder or drum should just touch that of the peat slab.
But upon this surface are fixed sharp spades, the length of which is just
equal to the thickness of the slab of peat, so that as soon as they reach
it they cut through it. These spades, being disposed in the four sides of
a pyramid of which the apex is in the axis of the cylinder or drum, cut
up the slab of peat into bricks of a corresponding size, slightly bevilled
towards the axis of the drum, in fact truncated pyramids. As the drum
revolves these bricks are carried onward in the cutters, and it is
necessary to remove them in order that they may be submitted to the
final process of air drying.
The whole surface of the drum being covered with a network of the
edges of the cutters, each row is furnished opposite to it in the interior
of the drum with a corresponding row of flat plates carried on rods per-
These bars are moveable to and fro
pendicular to a moveable bar.
through a space just equal to the height of the truncated pyramids, that
is, to the thickness of the peat bricks. By this arrangement the bricks
are dislodged from the cutters, and deposited on an inclined plane,
5 whence they are conveyed to the drying sheds in wagons, and upon
light trellis-formed trays, so arranged as that the air may easily pass
through and between them.
The waggons containing the peat bricks are now run into the drying

page_text: sheds on a tram or railway. These sheds are practically air-tight when
closed; but being so constructed as to allow a current of air to pass in
the direction of their length a fan blast of adequate power is driven
through them at a temperature of from 80° to 190° Fahrenheit, or more;
but below the boiling point. This air is heated by passing it in a ser-
pertine pipe through a steam chest, so as to acquire the necessary
temperature. The sheds have an oblong form, and are a little wider
than the tram or railway which passes through them. They have appro-
priate apertures for the entrance and exit of the air blast and doors for
the passage of the waggons. During this process of drying the tem-
perature of the air must be gradually raised, in order to prevent any
disruption of the bricks by the too sudden vaporization of their
moisture.
The duration of the drying process donands jointhe on the tempomature
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Sir Francis Charles Knowles in the Great Seal
Patent Office on the 31st October 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Sir FRANCIS
CHARLES KNOWLES, Baronet, of Lovell's Hill, in the County of Berks,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent bearing date the First day of May, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Francis Charles Knowles, Her
special licence that I, the said Francis Charles Knowles, my executors,
administrators, and assigns, or such others as I, the said Francis Charles
Knowles, my exccutors, administrators, and assigns, should at any 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 "IMPROVEMENTS IN THE PREPARATION OF PEAT FOR FUEL, AND IN AP-
PLIANCES OR APPARATUS FOR THE PURPOSE," upon the condition (amongst`

page_text: others) that I, the said Francis Charles Knowles, 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 Francis Charles Knowles, 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 thereof, that is to say :-
This Invention relates to the production of condensed peat in a form
convenient for consumption thereof by methods more economical than
those hitherto in use, and at all seasons of the year, excepting only
during actual frost.. I take the said peat from the bog deposit thereof,
either in the solid or in the pulpy state, and I cut up the same within
a vat armed with serrated Archimedean cutters in the form of screw
blades placed in pairs, one above the other, one being right handed and
one left handed, with their respective teeth opposed, each successive
pair deviating horizontally by a small angle from the position of the pair
immediately below it, as herein-after more exactly described. In each
pair of blades one is fixed in the vat or drum, the other revolves upon
an axis so that every tooth of the lower one is successively opposed to
every tooth in the one above it. A small interval, capable of simple
adjustment if need be, is left between the rows of opposing teeth; except
in the highest and the lowest blade both edges of the blades are serrated.
The vat containing these blades or cutters may be of any dimensions
depending on the motive power of the engine which drives them.
The vat itself (one or more, as the case may be) is open at the top
and at the bottom. It is placed vertically in a large cistern or tank
destined to receive the peat or peat pulp after laceration by the cutters
is completed.
A circulation of the raw material between the mass in the tank and
the upper opening of the vat is kept up by means of a set of dredging
buckets upon its endless chain, which continuously deliver the pulp
from below into the upper opening to be again passed through the
cutters.

page_text: When the peat is solid it must be macerated with water in the cutting
ápparatus, so as to reduce it to pulp. When it is completed the coally
ór pitchy parts of the peat are readily separable from the undecomposed
rushes or other vegetable matter, and they are in fact so separated by
appropriate sieves or strainers at the apertures below, through which the
mixture flows out of the tank. From this the watery pulp is conducted
to the filters in the second stage of the process by means of gutters
along which revolving Archimedean screw plates propel it, a mode of
propulsion well known and long in use.
The filtering apparatus consists of a strong iron chest capable of
sustaining a heavy pressure. It is furnished at the top with a ledge
on which is a bedding of caoutchouc. Upon this bedding rests a strong
iron plate full of small perforations. Above this, again surrounding it,
and flush each to each with the four sides of the chests, are boards
turning on hinges, and fitted at the angles of junction so as to form a
shallow water-tight compartment. The depth of this is such as to
admit one charge of peat pulp containing the quantity of solid matter
required for the bricks to be made after filtration of the water. Above
the perforations, when the apparatus is to be put in action, is placed a
cheap felt cloth, upon which the wet peat pulp is allowed to flow from
the tank or reservoir until the wooden compartment is filled. Con-
veniently connected with the filtering chest is an exhaust pipe, by
means of which through appropriate valves the air is pumped out by
the action of the engine until any required degree of pressure is exerted
upon the surface of the pulp. This pressure must be gradually
increased until all the water being filtered away the compression
solidifies the mass. The slab of compressed peat thus formed is now
to be carefully removed from the filter, and conveyed to the brick
cutter. For this purpose it is carefully placed upon a low waggon
running upon small iron wheels adapted to a tramway or a railway. At
the opposite sides of this waggon are firmly fixed two racks, which work
in two large pinions concentric with an iron or strong wooden cylinder.
This cylinder revolving round a fixed axis carries in the direction of its
rotation the waggon with its slab of peat which runs with its wheels
upon the tram or railway, so that in the absence of any obstacle the
surface of the cylinder or drum should just touch that of the peat slab;
but upon this surface are fixed sharp spades, the length of which is just
equal to the thickness of the slab of peat, so that as soon as they reach

page_text: it they cut through it: These spades, being disposed in the four sides of
a pyramid of which the apex is in the axis of the cylinder or drum, cut
up the slab of peat into bricks of a corresponding size slightly bevilled
As the drum
towards the axis of the drum, in fact truncated pyramids.
revolves these bricks are carried onward in the cutters, and. it is
necessary to remove them, in order that they may be submitted to the
final process of air drying.
The whole surface of the drum being covered with a network of the
edges of the cutters each row is finished opposite to it in the interior of
the drum with a corresponding row of flat plates carried on rods per-
pendicular to moveable bars. These bars are moveable to and fro through
a space just equal to the height of the truncated pyramids, that is to
the thicknes of the peat bricks. By this arrangement the bricks are
dislodged from the cutters and deposited upon an inclined plane, whence
they are conveyed to the drying sheds in waggons, and upon light
trellis-formed trays, so arranged as that the air may easily pass through
and between them.
<>
The waggons containing the peat bricks are now run into the drying
sheds on a tram or railway. These sheds are practically air-tight when
closed; but being so constructed as to allow a current of air to pass in
the direction of their length a fan blast of adequate power is driven through
them at a temperature of from 80° Fahrenheit to 190°, or more, but below
the boiling point. This air is heated by passing it in a serpentine pipe
through a steam chest, so as to acquire the necessary temperature. The
sheds have an oblong form, and are a little wider than the tram or
railway which passes through them. They have appropriate apertures
for the entrance and exit of the air blast, and doors for the passage of
the waggons. During this process of drying the temperature of the air
must be gradually raised, in order to prevent any disruption of the bricks
by the too sudden vaporization of their moisture.
The duration of the drying process depends jointly on the temperature
of the air and the velocity of the current, which may be accelerated at
discretion.
And having now described the nature of my said Invention, and in
what manner the same is to be performed, I declare that I claim,—
Firstly. The herein-before described method of treating peat in order
to prepare it for fuel,

page_text: Secondly. The use of an Archimedean peat cutter or lacerator con-
structed as above, and employed as described, in a tank furnished with
dredging buckets for the supply of peat to the vat containing such
cutters or lacerators for the purpose set forth.
Thirdly. The employment of a filter or percolator acted upon by
atmospheric pressure produced by exhaustion of the air in the chest
below the same, as and for the purposes set forth.
Fourthly. The use of a drum with the appliances, adjustments, and
apparatus pertaining thereto for cutting up peat slabs into bricks, as
described.
Fifthly. The drying of peat bricks by means of a heated fan blast
conveyed in pipes below the peat trays in waggons, and discharged
upwards through the roof of a drying house, as herein-before
described.
In witness whereof, I, the said Francis Charles Knowles, have
hereunto set my hand and seal, this Nineteenth day of October,
One thousand eight hundred and seventy-four.