IMPROVEMENTS IN THE RECOVERY OF ALKALI FROM THE LIQUID IN WHICH PROVISIONAL SPECIFICATION THE IN WHICH ESPARTO, WOOD, STRAW, OR OTHER MATERIAL HAS BEEN BOILED
Year: 1873

page_text: LETTERS PATENT to David Adam Fyfe and William Hadfield Bowers,
both of Manchester, in the County of Lancaster, for the Invention
of "IMPROVEMENTS IN THE RECOVERY OF ALKALI FROM THE LIQUID IN WHICH
PROVISIONAL SPECIFICATION left by the said David Adam Fyfe and
William Hadfield Bowers at the Office of the Commissioners of
Patents, with their Petition, on the 1st September 1878.
We, DAVID ADAM FYFE and WILLIAM HADFIELD BOWERS, both of
Manchester, in the County of Lancaster, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE RECOVERY OF ALKALI FROM
THE LIQUID IN WHICH ESPARTO, WOOD, STRAW, OR OTHER MATERIAL HAS BEEN
BOILED," to be as follows:-:

page_text: We have found it advantageous to promote or permit the combustion
of the charcoal or residium after it has been discharged from the retort,
whereby the greater part of the whole of the carbon is consumed, and a
residual ash containing a very large proportion of alkali is obtained.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said David Adam Fyfe and William Hadfield Bowers
in the Great Seal Patent Office on the 28th February 1874.
$
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, DAVID
ADAM FYFE and WILLIAM HADFIELD BOWERS, both of Manchester, in
the County of Lancaster, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent bearing date the First day of September, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs-and' suc-
cessors, give and grant unto us, the said David Adam Fyfe and William
Hadfield Bowers, Her special license that we, the said David Adam
Fyfe and William Hadfield Bowers, our executors, administrators, and
assigns, or such others as we, the said David Adam Fyfe and William
Hadfield Bowers, ours 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 Inven-
tion for "IMPROVEMENTS IN THE RECOVERY OF ALKALI FROM THE LIQUID IN WHICH
ESPARTO, WOOD, STRAW, OR OTHER MATERIAL HAS BEEN BOILED," upon the
condition, amongst others, that we, the said David Adam Fyfe and
William Hadfield Bowers, by an instrument in writing, under our hands
and seals, should particularly describe and ascertain the nature of the
said Invention and in what manner the same is 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.

page_text: NOW KNOW YE, that we, the said David Adam Fyfe and William
Hadfield Bowers, do hereby declare the nature of the said Invention,
and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement (and
accompanying Drawings), that is to say :-
Our Invention relates principally to the treatment of the liquid
resulting from the operation of boiling esparto, wood, straw, or other
material employed in the manufacture of paper, and has for its object to
recover a portion of the soda or other alkali employed in the said opera-
tion of boiling.
The principal method of recovery hitherto in use has consisted in
evaporating the said liquid to a dry or nearly dry state, and in burning
the residium, the ash resulting from such burning being lixiviated in
water.
When treating the said liquid we mix therewith about as much saw-
dust as will take up the said liquid, and we place the sawdust so treated
in a retort or in retorts, and subject it therein to a destructive distilla-
tion, and collect the acid, tar, gas, and other products which pass
over, and we recover the alkali from the residual charcoal or ash by
lixiviation.
The said liquid may be concentrated by evaporation before the addition
of the sawdust, if preferred or found to be convenient or suitable in any
The gas which passes over may be employed in lieu of fuel or for
purposes of illumination.
case.
We may employ other substances or materials than sawdust, as for
example, chaff, shove, or peat. In selecting such substances it is important
that they should be capable of yielding by distillation useful products,
which serve to render the operation more profitable.
As we now consider sawdust to be the most suitable when describing
our Invention, herein-after we will mention sawdust only in order to
avoid needless repetition
We prefer to dry or partly dry the sawdust before admitting the same
to the retort. For this purpose the sawdust may be placed on or fed on
to a metal floor heated by the waste heat from the furnace or by other

page_text: metal plates, or otherwise suitably formed. It has not been considered
to be necessary to exhibit the said floor in the Drawings, as the method
of formation will be readily understood. The hopper D is provided with
grooved rollers f;f, which are geared to revolve in contrary directions,
and receive motion from the driving shaft g by means of the pulleys and
strap h. The said rollers are set so that the points of the teeth approach
each other very closely, and they also revolve in contact or nearly in
contact with the sides of the hopper or with plates which can be “set
up" towards the said rollers, the object being to check the escape of
vapours through the hopper. Endless chains i are mounted on chain
pinions fixed on the shaft k, and on two pulleys 2, 1, and the said
chains are provided with scrapers m, each alternate link in each chain
being formed to clip a scraper, and to be secured thereto by means of a
bolt. The said scrapers extend across the bottom of the retort, and
travel thereupon from one end of the retort to the other when the shaft /
is caused to revolve. The said shaft receives motion from the driving
shaft through the wheel and pinion n, n.
g
The delivery end of the
retort opens into a down shoot o, which can be closed at any time by
means of the valve p, and the said shoot communicates with a chamber r,
which is provided with a hinged door. The retort communicates by
means of the pipes 8, 8, with a first condenser t, which communicates
by means of the pipe u with a main v, which leads to a condenser, or
which is itself immersed in water, and extended sufficiently to enable it

page_text: whereby the organic matters become carbonised, the residiuum being
discharged through the shoot o into a wagon or other receptacle placed
in the chamber 7. The said residiuum is withdrawn from the said
chamber at intervals, the valve p being closed before the door of the said
chamber is opened to prevent access of air to the interior of the retort.
The said residiuum on exposure to the air becomes incandescent, and the
contained carbon consumes until a residual ash is obtained, the said ash
consisting of alkali with a comparatively small proportion of impurities.
During the destructive distillation gases and vapours flow through the
pipes 8, 8, into the condensers, and pyroligneous or acetic acid and
vegetable tar result from the condensation of the said vapours.
After the said condensation a combustible gas remains, which gas may
be admitted into the furnace to aid in heating the retort, or may be
employed to heat pans in which the waste liquors are or may be concen-
trated by evaporation previously to the addition thereto of the sawdust,
or the said gas may be otherwise employed.
If required for illuminating purposes it may be necessary to treat the
said gas with carbonising agents.
Having now fully described and indicated the nature of our said
Invention, and our arrangements for carrying the same into practical
effect, we would remark that we do not confine the application of our
Invention to the recovery of alkali from the waste liquors arising from
the boiling of paper materials, as the said Invention may be applicable
with advantage to the recovery of alkali from the liquors in which other
materials have been boiled, and in conclusion we would have it to be
distinctly understood that we claim,―
First. The process for recovering alkali from such waste liquors as
herein referred to, substantially as hercin set forth and indicated.
Secondly. Absorbing or taking up such waste liquors by means of
sawdust or other substances of the nature herein indicated, and subse-
quently subjecting the said sawdust or substances to destructive
distillation in retorts, whereby useful products are obtained in addition
to the recovered alkali.

page_text: Drawings.
In witness whereof, we, the said David Adam Fyfe and William
Hadfield Bowers, have hereunto set our hands and seals, this
day of February, in the year of our Lord One 5
thousand eight hundred and seventy-four.
D. A. FYFE.
Signed and sealed by the said David
Adam Fyfe and William Hadfield
Bowers in the
presence of
EDWARD K. DUTTON,
Agent to the Patentees,
3, Princess Street,
Manchester.
W. H. BOWERS.
(L.S.)
(L.S.)