IMPROVE- MENTS IN SCOURING WOOL AND IN UTILIZING THE PRODUCTS RESULTING THEREFROM
Year: 1873

page_text: LETTERS PATENT to George Lunge, of South Shields, in the County
of Durham, Doctor of Philosophy, for the Invention of "IMPROVE-
MENTS IN SCOURING WOOL AND IN UTILIZING THE PRODUCTS RESULTING
THEREFROM." -A communication from abroad by Dr. Karl Kraut,
PROVISIONAL SPECIFICATION left by the said George Lunge at the
Office of the Commissioners of Patents, with his Petition, on the
23rd December 1873.
I, GEORGE LUNGE, of South Shields, in the County of Durham,
Doctor of Philosophy, do hereby declare the nature of the said Inven-
tion for "IMPROVEMENTS IN SCOURING WOOL AND IN UTILIZING THE PRODUCTS
RESULTING THEREFROM," being a communication to me from abroad by Dr.
Karl Kraut, Professor of Chemistry, Hanover, in the Empire of Germany,
to be as follows:-
-
It is well known that the raw sheep's wool contains large quantities
of "sweat"
and other impurities, and that therefore the wool before

page_text: being fit for spinning and weaving must undergo the operation of
"scouring."
The "sweat" from sheep's wool contains both fatty matters insoluble
in water and saline matters which are soluble in water, and the latter,
which are also known by the name of "suint," are if extracted by
themselves capable of yielding by evaporation and calcination an impure
carbonate of potassium.
The operation of scouring is mostly carried on so as to make the
greasy or fatty matters soluble in water by the help of alkalies, some-
times with the addition of silicate of soda or of soap, or in some other
way, and removing them along with the "suint" by washing in warm
water. In this method of treatment it is not easily practicable to save
the potash contained in the "suint," and it is therefore lost in the
washing water, together with the alkalies which have been employed.
In some cases however the "suint" is first extracted from the wool
by means of cold water in order to be treated for the recovery of the
potash, as above mentioned, and the wool is subjected in a subsequent
operation to the alkaline treatment for the removal of fatty matters. If
fixed alkalies are used in this second operation they cannot as a rule be
profitably recovered, and they are therefore lost.
The present Invention consists in carrying on the scouring process in
one operation, as in the first mentioned case, but instead of using the
alkalies of trade a portion of the carbonate of potassium recovered from
a previous operation is used, and the scourings are collected in order to
recover from them both the potash employed and that contained in or
obtainable from the wool operated upon.
This process is carried on as follows, although it may be varied in
details without interfering with or departing from the principles of this
Invention :-The raw wool is washed in the ordinary apparatus by means
of warm water, to which carbonate of potassium has been added in
sufficient quantity. In ordinary cases each five tons of wool require
two hundredweight of potash containing eighty per cent. of carbonate
of potassium, but this quantity will vary to some extent with the quality
of the wool employed. The washing waters are collected in tanks, in
which they are allowed to stand until the sand and other solid impurities
subside. The supernatant liquor is then evaporated to dryness, and the
residue heated in the bed of a furnace until it takes fire and burns off,

page_text: such result being assisted by stirring the residue with the usual furnace
tools. The result of this process is an ash, which is often mixed with
carbonaceous matter containing, firstly, the carbonate of potassium
employed for scouring, and secondly, the potassium present in the wool
employed, the latter being also mainly in the state of carbonate. The
ash is then submitted to a process of methodical lixiviation, which yields
a solution more or less pure of carbonate of potassium. One portion of
such carbonate of potassium is used for scouring a fresh quantity of
wool, and the portion not so employed is evaporated to dryness and
calcined, yielding a particularly fine kind of potash.
It is of great importance to diminish the quantity of water employed
for washing the wool as much as possible since it must all be evaporated
for the purpose of recovering the potash. It is therefore advisable to
conduct the liquid in which the wool has been last washed into another
vessel, in which the wool is treated in the first instance, or even to use
more than two vessels in this operation, but always in such a way that
the washing water travels the opposite way to the wool. The fresh wool
is therefore in contact with a liquid almost saturated, whilst the nearly
pure wool is in contact with fresh water.
In order to prevent a loss of potash in the lyc it is advisable to pass
the wood through squeezing rolls when transferring it from one compart-
ment of the washing apparatus to the next following one, as has
sometimes been previously done in the usual process of scouring.
It is not necessary to let the scourings stand in the settling tanks
until all impurities have subsided, provided that most of the sand is thus
removed; on the contrary, it is preferable to evaporate the lyes in a
turbid state, as the turbidity is to some extent caused by salts of lime,
and the presence of lime is advantageous for burning the potash to a
white state.
The apparatus for evaporating the lyes can be constructed in various
ways. One, which has been found very useful for this purpose, consists
of a combination of a furnace, with an iron pan fixed behind the same
and at a higher elevation, so that liquor contained in the pan is first
concentrated by the hot air escaping from the furnace being conducted
over its surface and then run on to the bed of the furnace, where it is
brought to dryness; the residue then takes fire, and thus assists the heat
proceeding from the fuel in the fire-place. Another pan or pans can be

page_text: arranged over the first or over the furnace, or both, to serve for a
previous heating of the lye. The pipes or shoots connecting one pan
with another, or with the furnace, must be wide and easily accessible for
the purpose of being cleansed. It is also expedient to run the upper
portion of the liquor contained in the settling tanks, which is compara-
tively clear, into the upper pans used for the previous heating, but to
run the lower and more muddy portion of liquor from the settling tanks
into the pan behind the furnace, which receives its heat from above.
In this way the formation of a deposit in the upper heating pans, which
would greatly impede the evaporation, can be to a great extent pre-
vented.
If the ash obtained by calcination is not burnt white, but contains
much carbonaceous matter, it is very difficult to obtain therefrom the
whole of the carbonate of potassium by lixiviation. In this case the
carbonaceous mass after being lixiviated is added to the residue from
evaporating another portion of lyc, and calcined along with the same,
when the potash salts can be more easily extracted by lixiviation.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Lunge in the Great Seal Patent Office on
the 23rd June 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
LUNGE, of South Shields, in the County of Durham, Doctor of Philosophy,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of December, 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 me, the said George Lunge, Her special
licence that I, the said George Lunge, my executors, administrators,
and assigns, or such others as I, the said George Lunge, 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 and Ireland, the Channel

page_text: Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN SCOURING
WOOL AND IN UTILIZING THE PRODUCTS RESULTING THEREFROM,” being a com-
munication to me from abroad by Dr. Karl Kraut, Professor of Chemistry,
Hanover, in the Empire of Germany, upon the condition (amongst
others) that I, the said George Lunge, 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 tho said Letters Patent.
NOW KNOW YE, that I, the said George Lunge, do hereby declaro
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, that is to say:-
It is well known that the raw sheep's wool contains large quantities
of "sweat" and other impurities, and that therefore the wool before
being fit for spinning and weaving must undergo the operation of
scouring."
"
The "sweat" from sheep's wool contains both fatty matters insoluble
in water, and saline matters which are soluble in water, and the latter,
which are also known by the name of "suint," are if extracted by
themselves capable of yielding by evaporation and calcination an impure
carbonate of potassium.
The operation of "scouring" is mostly carried on so as to make the
greasy or fatty matters soluble in water by the help of alkalies, some-
times with the addition of silicate of soda or of soap, or in some other
way, and removing them along with the "suint" by washing in warm,
water. In this method of treatment it is not easily practicable to save
potash contained in the "suint," and it is therefore lost in the washing
water, together with the alkalies which have been employed.
In some cases however the "suint" is first extracted from the wool
by means of cold water in order to be treated for the recovery of the
potash, as above mentioned, and the wool is subjected in a subsequent
operation to the alkaline treatment for the removal of fatty matters. If
fixed alkalies are used in this second operation they cannot as a rule be
profitably recovered, and they are therefore lost.

page_text: The present Invention consists in carrying on the scouring process in
one operation, as in the first mentioned case, but instead of using the
alkalies of trade a portion of the carbonate of potassium recovered from
a previous operation is used, and the scourings are collected in order to
recover from them both the potash employed and that contained in or
obtainable from the wool operated upon.
This process is carried on as follows, although it may be varied in
details without interfering with or departing from the principles of this
Invention:-The raw wool is washed in the ordinary apparatus by means
of warm water, to which carbonate of potassium has been added in
sufficient quantity. In ordinary cases each five tons of wool require
two hundredweight of potash containing eighty per cent. of carbonate
of potassium, but this quantity will vary to some extent with the quality
of the wool employed. The washing waters are collected in tanks, in
which they are allowed to stand until the sand and other solid impurities
subside. The supernatant liquor is then evaporated to dryness, and the
residue heated in the bed of a furnace until it takes fire and burns off,
such result being assisted by stirring the residue with the usual furnace
tools. The result of this process is an ash, which is often mixed with
carbonaceous matter containing, firstly, the carbonate of potassium
employed for scouring, and secondly, the potassium present in the wool
employed, the latter being also mainly in the state of carbonate. The
ash is then submitted to a process of methodical lixiviation which yields
a solution more or less pure of carbonate of potassium. One portion
of such carbonate of potassium is used for scouring a fresh quantity of
wool, and the portion not so employed is evaporated to dryness and
calcined, yielding a particularly fine kind of potash.
It is of great importance to diminish the quantity of water employed
for washing the wool as much as possible since it must all be evaporated
for the purpose of recovering the potash. It is therefore advisable to
conduct the liquid in which the wool has been last washed into another
vessel, in which the wool is treated in the first instance, or even to use
more than two vessels in this operation, but always in such a way that
the washing water travels the opposite way to the wool. The fresh wool
is therefore in contact with a liquid almost saturated, whilst the nearly
purc wool is in contact with fresh water.
In order to prevent a loss of potash in the lyc it is advisable to pass
the wool through squeezing rolls when transferring it from one compart-

page_text: ment of the washing apparatus to the next following one, as has
sometimes been previously done in the usual process of scouring.
It is not necessary to let the scourings stand in the settling tanks
until all impurities have subsided, provided that most of the sand is thus
removed; on the contrary, it is preferable to evaporate the lye in a
turbid state, as the turbidity is to some extent caused by salts of lime,
and the presence of lime is advantageous for burning the potash to a
white state.
The apparatus for evaporating the lye can be constructed in various
ways. Onc, which has been found very useful for this purpose, consists
of a combination of a furnace, with an iron pan fixed behind the same
and at a higher elevation, so that liquor contained in the pan is first
concentrated by the hot air escaping from the furnace being conducted
over its surface, and then run on to the bed of the furnace, where it is
brought to dryness; the residue then takes fire, and thus assists the heat
proceeding from the fuel in the fire-place. Another pan or pans can be
arranged over the first or over the furnace, or both, to serve for a
previous heating of the lye. The pipes or shoots connecting one pan
with another, or with the furnace, must be wide and easily accessible for
the purpose of being cleansed. It is also expedient to run the upper
portion of the liquor contained in the settling tanks, which is compara-
tively clear, into the upper pans used for the previous heating, but to
run the lower and more muddy portion of liquor from the settling tanks
into the pan behind the furnace which receives its heat from above.
In this way the formation of a deposit in the upper heating pans, which
would greatly impede the evaporation, can be to a great extent pre-
vented.
If the ash obtained by calcination is not burnt white, but contains
much carbonaceous matter, it is very difficult to obtain therefrom the
whole of the carbonate of potassium by lixiviation. In this case the
carbonaceous mass after being lixiviated is added to the residue from
evaporating another portion of lye, and calcined along with the same,
when the potash salts can be more easily extracted by lixiviation.
Having thus described and ascertained the nature of the said Inven-
tion, and in what manner the same is to be performed, I would observe
in conclusion that what I consider novel and original, and therefore claim
as constituting the Invention secured to me by the said herein-before in

page_text: part recited Letters Patent are, the several processes and methods of
treatment in scouring wool, substantially as and for the purposes herein..
before described and set forth.
In witness whereof, I, the said George Lunge, have hereunto set
my hand and seal, this Twenty-second day of June, in the year i
of our Lord One thousand eight hundred and seventy-four.