PROVEMENTS IN THE MANUFACTURE OF PUL.P
Year: 1853

page_text: LETTERS PATENT to Charles Townsend Hook, of Tovil House,.
Maidstone, in the County of Kent, for the Invention of
PROVEMENTS IN THE MANUFACTURE OF PUL.P."
PROVISIONAL SPECIFICATION left by the said Charles Townsend
Hook at the Office of the Commissioners of Patents, with his
Petition, on the 14th September 1853.
I, CHARLES TOWNSEND HOOк, of Tovil House, Maidstone, in the
County of Kent, do hereby declare that the nature of my Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF PULP" to be as follows:-
The improvement consists in a novel method of distributing chemical
solutions over the surface of the fibrous material. I distribute the
chemical solution over the surface of the material operated on by
forcing it, by means of pumps or other mechanical means, through a
rotatory tube, having a slit in it in the direction of its length, which
tube revolving (by gearing) within the circular vessel containing the
fibrous material equally distributes the solution over the surface. The

page_text: liquor drained through is collected at the bottom of the vessel, drawn
from thence by the pump, and is again forced through the tube as
before. The liquor I prefer to use is hydrate of soda of 11° to 14°
of Beamé
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Charles Townsend Hook in the Great Scal
Patent Office on the 14th March 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
CHARLES TOWNSEND HOOK, of Tovil House, Maidstone, in the County
of Kent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of September, in the
year of our Lord One thousand eight hundred and fifty-three, in the
seventeenth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Charles Townsend Hook,
Her special licence that I, the said Charles Townsend Hook, my
executors, administrators, and assigns, or such others as I, the said
Charles Townsend Hook, 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 law
fully 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 MANUFACTURE OF PULP," upon
the condition (amongst others) that I, the said Charles Townsend Hook,
by an instrument in writing under my hand and seal, should particu-
larly 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 Charles Townsend Hook, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement thereof (that is to say):

page_text: The Invention consists of an improved method of distributing che
mical and other solutions over the surface of fibrous substances when
about to convert them into pulp. For this purpose I employ an iron
or other vessel, preferring it to be of a cylindrical form and of about
twelve feet diameter, and five feet deep; but these dimensions may be
varied. This vessel has a cover and perforated false bottom, and it has
a standard fixed upright in its centre; supported by this standard, and
working in a bearing at the top thereof, there is a tube revolving hori-
zontally a few inches below the level of the top of the side of the
vessel, and made long enough beyond each side of the standard just
to clear, the interior sides of the vessel. This tube has narrow slits cut
in its under surface in the direction of its length, increasing in width.
as they approach the ends, and varying, say, from one twentieth inch
next the centre to one fifth inch next the outer ends. Care should be
taken that where the tube is left blank in one arm or projection
beyond the standard, at the same distance from the outer end of the
other arm there shall be a slit, and vice versâ; or, in place of slits, the
tube may be pierced with numerous small holes, increasing in number
or size as they approach the outer ends of the arms. At the centre of
this tube is a branch tube or pipe fixed upright, and at a right angle to
the horizontal one, which is continued through the cover of the vessel
to allow a bevil or spur wheel to be keyed on it, in order to its being
driven by another wheel in a usual manner, or it may receive motion
by a pulley and strap or otherwise. This upright pipe terminates in a
stuffing box which connects it with a fixed pipe, the other end of which
is connected with a vessel, which I prefer to be of about forty gallons
capacity, placed above the level of the distributing tube, but as little
so as conveniently may be. This vessel I call the heater, and it is
fitted with a coil of pipes to be filled with steam, or a double bottom
and sides may be used in order to keep the solution employed at a
boiling temperature. A pipe leads from the bottom of the vessel con-
taining the fibrous material under process to a pump. I prefer one that
will lift from seventy to one hundred gallons per minute, when the
vessel is of the dimensions above given. This pump elevates the
liquor as it comes below the false bottom into "the heater" above...

page_text: There is a cock or valve on the pipe leading from below the false
bottom of the vessel to draw the liquor off when desired. The appa-
ratus having been constructed and arranged as described, the mode
of working is as follows, supposing straw to be the fibrous substance
operated on, and it is a very suitable material for the purpose, though
the process is available for other fibrous substances:-The straw
having been cut into lengths from about a quarter to three quarter
inch, and as much dust, knots, corn, &c. removed from it as possible
by sifting and blowing, or by other similar means, is then placed
into the vessel with a false bottom, which is filled to within a few
inches of the distributing tube, which is then put in motion at a rate
of from five to ten revolutions per minute. The steam is turned
on to "the heater;" from twelve to fifteen gallons to each cwt. of
straw operated on of boiling alkaline liquor is introduced into "the
heater," which will be quickly showered down from the two arms of the
horizontal tube over the straw; this first quantity may be liquor which
has been previously used on a like quantity of fibre. A boiling solu-
tion of fresh caustic soda or potash, otherwise hydrate of soda or potash,
of a strength of from 11° to 14° Beaumé, is next introduced into "the
heater," and is quickly dispersed over the straw. I would remark that
it is not essential that the used alkaline solution and the fresh hydrate
should be kept separate; they may, if preferred, be mixed in a receiver
before using. When the necessary quantity has been distributed over
the straw (which will be from twenty-two to twenty-eight gallons for
every hundredweight of straw in the vessel) the pump is to be set to
work, by which the liquor collected below the false bottom will be
elevated into the heater," and from thence it is showered down by
the distributing arms over the surface of the straw. This action is
continued from eight to twelve hours The distributing tube is then
stopped. The pump is then caused to lift a sufficient quantity of the
liquor for the next operation (say twelve to fifteen gallons for each
hundredweight of straw) into a receiver above, and is then stopped;
the valve at the bottom of the vessel is opened, and the liquor drains off
from below the false bottom. A supply of hot water, about forty to
fifty gallons to each hundredweight of straw is then furnished to "the

page_text: heater," whence it is showered down on the straw. The steam is shut
off from the heater," and cold water is showered down till the liquor
drains off clear. Sulphuric acid is added in the last two hundred
gallons of cold water, at the rate of about two gallons to one ton of
straw, which improves the color. The remainder of the alkaline liquor
drained off from the straw, and a portion of the hot washings should
be evaporated, and the product burnt in a furnace or oven, by which
a portion of alkali may be regained. The straw is then emptied into
poaching engine," where it is bleached in a solution of bleaching
powder of about a strength 2° Beaumé, or a steeping chest can be used
with a less quantity of bleaching solution, but which should be of a
strength of about 8° Beaumé. This must be stirred often. I find
straw to take a longer time in bleaching than rags. It is then well
washed and drained and put into a beating engine, which quickly
converts it into a pulp. I have found it best to keep the straw or
other fibre at a temperature of from 70° to 80° Fahrenheit while
bleaching.
I do not confine myself to the details above stated, so long as the
peculiarity of my Invention is retained. What I claim is, the mode
above described of distributing chemical solutions and water over the
surfaces of fibrous materials suitable for making pulp.
In witness whereof, I, the said Charles Townsend Hook, have
hereunto set my hand and seal, this Eleventh day of March,
in the year of our Lord One thousand eight hundred and fifty-
four
Witness,
CHARLES TOWNSEND HOOK. (L.S.)
GEORGE WHITE,
Timber Merchant,
Maidstone.