IMPROVEMENTS IN BOILERS FOR TREATING WOOD AND FIBROUS SUBSTANCES, REQUIRING GREAT HEAT AND PRESSURE
Year: 1871

page_text: LETTERS PATENT to Benjamin Brown, of. Ely Fibre Works, Cardiff,
in the County of Glamorgan, for the Invention of "IMPROVEMENTS
IN BOILERS FOR TREATING WOOD AND FIBROUS SUBSTANCES, REQUIRING GREAT
HEAT AND PRESSURE."
Sealed the 12th December 1871, and dated the 19th September 1871.
PROVISIONAL SPECIFICATION left by the said Benjamin Brown at
the Office of the Commissioners of Patents, with his Petition, on
the 19th September 1871.
I, BENJAMIN BROWN, of Ely Fibre Works, Cardiff, in the County of
Glamorgan, do hereby declare the nature of the said Invention for
" IMPROVEMENTS IN BOILERS FOR TREATING WOOD AND FIBROUS SUBSTANCES
REQUIRING GREAT HEAT AND PRESSURE," to be as follows:-
This Invention relates to a novel arrangement of apparatus to be used
in the preparation or reduction of wood and other fibres requiring great
pressure to half stuff for the manufacture of paper therefrom, the object

page_text: being to effect an economy in the operation. To this end I employ a
cylindrical boiler which I mount horizontally in a brick or other furnace.
This boiler I fit with hollow trunnions upon which it is free to turn.
The ends of the boiler extend beyond the furnace walls, and to prevent
an indraught of air at the openings through which the ends of the
boiler project I construct the boiler with ring flanges which enter
annular recesses in the end walls of the furnace. The opposite ends of
the boiler I provide with man-holes through which the boiler is charged
and discharged. These man-holes I make oval. This position of the
man-holes will greatly facilitate the filling and emptying of the boiler,
and by making the man-holes oval I am enabled to fit them with an
inner flange and yet allow of the lid being brought to the back of such
flange for the purpose of being held against the flange by the pressure
of the steam acting on the lid. The hollow trunnions admit of stationary
pipes connected with safety or other valves being inserted therein.
Thus the internal pressure to which the boiler is exposed may be
regulated with the same facility as in fixed boilers, and the pressure on
the boiler estimated and regulated. The inner ends of the steam pipes
I bend upwards nearly to the top of the boiler, and fit with a cage or
cover to prevent the admission of fibres thereto. The furnace over
which the boiler revolves may be provided with one or two fire-places,
the heat acting uniformly on the boiler, and the outlet of the flues so
arranged that with the two chimneys on the top of the arched flue the
draught of the furnace will be such as to equalize the distribution of the
heat over that portion of the boiler which is exposed to the flame and
heated gases.
An incidental advantage of this construction of boiler is that it will
not need cooling with cold water to enable it to be discharged. It is only
necessary to draw the fires, and when the pressure has fallen to remove
the covers from the man-holes, when the boiler will with little
assistance from the attendant discharge its contents into a suitable
The Invention
receptacle or receptacles provided to receive the same.
is illustrated by the accompanying Drawings. There is a shelf (not
shewn) which extends nearly from end to end on the side of the boiler
opposite to the man-holes. The shelf performs two functions; it will act
11
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page_text: .
carried up with it, and then fall on to a different portion of the boiler.
For safety I provide the boiler with a pressure guage, a thermometer,
and two double safety valves, as well as with a self-acting (when
necessary) air escape valve. To insure that no strain shall come upon
the boiler by its revolution I mount the trunnion furthest from the
driving end on friction wheels. I do not pass any steam into the boiler,
but heat it solely by the furnace.
The tank above the boiler ensures hot water when required on
emptying the boiler, and thus utilizing the spare heat from the
furnace.
With the above arrangement of boiler much less caustic liquor will be
required and the chances of charring will be avoided, by which means a
good fibre at a smaller cost will be obtained. The boiler may thus be
charged and emptied with great facility, and by avoiding the use of cold
water sudden contraction and injury to the boiler will be prevented.
Anthracite coal or coke will be used to keep the boiler and flues free
from soot.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Benjamin Brown in the Great Seal Patent
Office on the 18th March 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BENJAMIN
BROWN, of Ely Fibre Works, Cardiff, in the County of Glamorgan, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of September, in the
year of our Lord One thousand eight hundred and seventy-one, in the
thirty-fifth year of Her reign, did, for Herself, Her heirs and successors;
give and grant unto me, the said Benjamin Brown, Her special
licence that I, the said Benjamin Brown, my executors, adminis-
trators, and assigns, or such others as I, the said Benjamin
Brown, 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

page_text: and Ireland, the
Unannel Islands, and Isle of Man, an invention for
"IMPROVEMENTS IN BOILERS FOR TREATING WOOD AND FIBROUS SUBSTANCES
REQUIRING GREAT HEAT AND PRESSURE," upon the condition (amongst
others) that I, the said Benjamin Brown, 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 Benjamin Brown, 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 Drawing hereunto
annexed, and to the letters and figures marked thereon (that is
to say) :—
This Invention relates to a novel arrangement of apparatus to be used
in the preparation or reduction to half stuff (for the manufacture of
paper) of wood and other vegetable fibres requiring great pressure in
their reduction, the object being to effect an economy in the operation.
To this end I employ a cylindrical boiler which I mount horizontally in
a brick or other furnace. This boiler I fit with hollow trunnions upon
which it is free to turn. The ends of the boiler extend beyond the
furnace walls, and to prevent an indraught of air at the openings
through which the ends of the boiler project, I construct the boiler with
ring flanges which enter annular recesses in the end walls of the furnace.
The opposite ends of the boiler I provide with man-holes (by preference
oval) through which the boiler is charged and discharged.. This position
of the man-holes will greatly facilitate the filling and emptying of the
boiler, and by making the man-holes oval I am enabled to fit them
with an inner flange and yet allow of the lid being brought to the
back of such flange for the purpose of being held against the flange
by the pressure of the steam acting on the lid, as is well understood
with respect to the mud hole covers of boilers. The hollow trunnions
admit of stationary pipes a', a', connected with safety or other valves
being inserted therein. This allows of the internal pressure to which the
boiler is exposed being regulated with the same facility as in fixed

page_text: boilers. The inner ends of the steam pipes a' I bend upwards nearly to
the top of the boiler and fit with a cage or cover to prevent the
admission of fibres thereto, or the pipes may terminate in a flange, as
shewn at Figs. 4; to which a protecting plate is applied to receive the
droppings from the upper side of the boiler and prevent the open end
being clogged by the fibres. This covering plate I bolt to the flange,
inserting filling blocks, as shewn, to provide a free space for the passage
of steam into the pipe. The furnace over which the boiler revolves
may be provided with one or more fire-places, and the outlets for the
heated gases from the furnace I so arrange as to equalize the distribution
of the heat over that portion of the boiler which is exposed to the
flame and heated gases.
'
The Invention is illustrated by the accompanying Drawing, in which
Fig. 1 shews in side elevation the boiler and the driving gear connected
therewith, the furnace in which the boiler is mounted being shewn in
section. Fig. 2 is a transverse vertical section of the same, shewing
also in section flues to which the heated gases from the furnace are
conducted for the purpose of heating a water tank placed above those
flues. Fig. 3 is an end elevation of the boiler and furnace, shewing the
mechanism for giving a slow rotary motion to the boiler.
A, A, is the cylindrical boiler fitted with hollow trunnions a, a, which
turn in bearings in end frames B, B. This boiler is mounted in a
furnace C, and its ends A¹, A', project beyond the end walls thereof, as
shewn at Fig. 1. In order to close the openings in the end walls and to
prevent as far as possible the indraught of air to the furnace through
the same, the boiler is provided with flanges a¹ which enter grooved
rings a fitted in the openings in the end walls. The fire-place or places
I arch over with fire-brick as shewn at C¹ in order to deflect the flame
and prevent it from striking directly on to the middle of the boiler.
Above the boiler, supported on suitable girders, is a serpentine flue D,
above which is placed a closed water tank E; this flue is brought into
connection with the furnace C by vertical flues c, and it also connects
with the chimney shaft F. By this arrangement the heated gases
escaping from the furnace are caused to heat the water contained in the
tank E, and prepare it for use in renewing the charge in the boiler A, or
for other purposes, such as washing the boiled stuff. The boiler is fitted
with a plate or shelf a³, which extends nearly from end to end thereof,

page_text: and on the side of the boiler opposite to the man-holes. This shelf
extends nearly the whole length of the boiler, but it is made shorter
than the boiler so as to clear the gusset stays and fixed pipes. The
shelf as performs two functions; it will act as a counterbalance to the
weight of the man-holes, and also as a stirrer to the mass of chips of
wood or other fibrous material in the boiler, as at every revolution a
fresh portion will be carried up with it and then fall on to a different
portion of the boiler. For safety I provide the boiler with a pressure
gauge, a thermometer, and two double safety valves, as well as with a
self-acting (when necessary) air escape valve. To insure that no torsion
strain shall come upon the boiler by its revolution I prefer to mount the
trunnions furthest from the driving end on friction rollers. I would
remark that I do not pass any steam into the boiler, but heat it solely
by the furnace.
An important practical advantage consequent on my improved
construction of boiler is that the boiler will not need cooling with cold
water to enable it to be discharged. It is only necessary to draw the
fires, and when the pressure has fallen to remove the covers from the
man-holes. The boiler will then with little assistance from the
attendant discharge its contents into a suitable receptacle or receptacles
provided to receive the same.
The tank E above the boiler provides the hot water required for
renewing the charge after the emptying of the boiler, through the
utilization of the spare heat from the furnace that would otherwise
escape through the chimney.
With the above arrangement of boiler much less caustic liquor will be
required than heretofore in the reduction of wood fibre, and the chances
of charring will be avoided, by which means a good fibre at a smaller
cost will be obtained. The boiler may also be charged and emptied
with great facility, and by avoiding the use of cold water sudden con- ;
traction and injury to the boiler will be prevented. Anthracite coal or
coke will, by preference, be used to keep the boiler and flues free
from soot.
Having now set forth the nature of my Invention of "Improvements
in Boilers for Treating Wood and Fibrous Materials requiring great Heat
and Pressure," and explained the means of carrying the same into effect,

page_text: I wish it to be understood that under the above in part recited Letters
Patent I do not claim a boiler revolving over a fire; but what I claim
is, the general arrangement of the boiler as herein-before described, and
for the purpose stated.
In witness whereof, I, the said Benjamin Brown, have hereunto
set my hand and seal, the Fifteenth day of March, in the
year of our Lord One thousand eight hundred and seventy-
two.