IMPROVEMENTS IN THE MANUFACTURE OF ALUM, AND IN THE MODE OF AND APPARATUS FOR CONDENSING OR DESTROYING GASES ARISING THEREFROM
Year: 1859

page_text: LETTERS PATENT to Peter Spence, of Pendleton, in the County of
Lancaster, Manufacturing Chemist, for the Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF ALUM, AND IN THE MODE OF AND APPARATUS FOR
CONDENSING OR DESTROYING GASES ARISING THEREFROM."
Sealed the 16th August 1859, and dated the 21st February 1859.
PROVISIONAL SPECIFICATION left by the said Peter Spence at the Office_
of the Commissioners of Patents, with his Petition, on the 21st February
1859.
I, PETER SPENCE, of Pendleton, in the County of Lancaster; Manufacturing.
Chemist, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN THE MANUFACTURE OF ALUM, AND IN THE MODE OF & APPARATUS FOR
CONDENSING OR DESTROYING GASES ARISING THEREFROM," to be as follows:-
My Invention refers to that method of making alum, for which Letters
Patent were granted to me, bearing date Nov 27th, 1845, numbered
10,970. According to the Specification thereof, the shale was digested in a
vessel from which the liquor was then drawn off and treated with ammonia in
another vessel. According to my present improvement I admit ammonia during
the digestion of the shale, so that the whole is conducted in one vessel. The
vessel employed for the purpose is of lead or other suitable material, and
supplied with a cover which may be wholly or partly removed, but capable of
being cemented or otherwise rendered tight. The gases evolved I conduct
into a condenser formed by pipes or channels surrounded by water, but

page_text: provided with an opening forming a trap against the escape of gas, but allow-
ing water to pass into the pipes, and the products of condensation pass into a
drain. The mixed gases which are not condensed I cause to pass along a
suitable channel into the sulphur ovens employed in the manufacture of
sulphuric acid, where they become destroyed.
The condenser above described is applicable to the system of separate vessels
for digestion and treating with ammonia according to my Patent of 1845
aforesaid.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Peter Spence in the Great Seal Patent Office on the
20th August 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PETER
SPENCE, of Pendleton, in the County of Lancaster, Manufacturing Chemist,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of February, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Peter Spence, Her special license that I, the said Peter Spence,
my executors, administrators, and assigns, or such others as I, the said
Peter Spence, 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 Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF ALUM, AND IN THE MODE OF AND APPARATUS FOR CONDENSING
OR DESTROYING GASES ARISING THEREFROM," upon the condition, amongst others,
that I, the said Peter Spence, by an instrument in writing under my hand
and seal, 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 Peter Spence, do hereby declare the
'nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and, ascertained in and by the following
statement and accompanying Drawing (that is to say):-

page_text: My Invention refers to that method of making alum, for which Letters
Patent were granted to me, bearing date November the Twenty-seventh, One
thousand eight hundred and forty-five, No. 10,970. According to my present
improvement I admit ammonia during the digestion of the shale, so that the:
whole may be conducted in one vessel. The gases evolved I conduct into a
condenser of peculiar arrangement, which condenser is applicable to the system
of digesting and treating with ammonia, according to my Patent of One thou-
sand eight hundred and forty-five aforesaid, when ammoniacal gas liquor
is used.
Having thus alluded to the general features of my Invention, I will proceed
to point out the method I adopt for carrying it into practical operation, pre-.
mising, however, that the quantities mentioned, and the precise apparatus.
described are not essential, but are merely given as I have found them to'
answer; and as an example, by which all competent persons will be enabled.
to practice the Invention, that is to say, I use a vessel forty feet long, nine
feet wide, and four feet deep, built of brickwork, and lined with lead. There;
being an ordinary fire-place and flue beneath. This vessel is provided with a
false bottom of tiles, with spaces at the joints, and two-thirds of its top are
permanently covered with lead; the remaining third is furnished with a move->
able cover composed of wood, covered with lead. This part of the cover
being removed, I place in the vessel about twenty tons of shale, and nearly fill
up with diluted sulphuric acid of the strength of about 1.35, specific gravity;
into an iron boiler, fitted with a fire-place and flue, I introduce ammoniacal
gas liquor, and this boiler is provided with a pipe which leads into the first-
mentioned vessel containing the shale, the said pipe dipping eight or ten inches
under the liquor, and provided with a T end, in which are numerous per-
forations. The fires in both vessels being lighted, the sulphuric acid in the
first-mentioned becomes charged with alumina, into which the ammonia;
evolved in the boiler passes by the perforated pipe, during which a constant,
stream of gas liquor is flowing in at one end of the boiler and passing out at.
the other so as to keep up a sufficient supply of ammonia, and thus the two
operations of digesting the shale and charging with ammonia are carried on at
the same time, and in one vessel. I would remark, however, that I do not
confine myself to this precise arrangement, for it will be evident that the same
principle of digestion and treating with ammonia simultaneously may be
carried out by passing the ammonia into an intermediate vessel through which
the liquor from the shale may be caused to circulate while the digestion is
proceeding. It will be found that the completion of the process will have
taken place in about twenty-four hours, and the liquor is then drawn off for

page_text: crystallization. The shale, however, is not yet exhausted, and two more
charges of sulphuric acid may be added, the operations above described being
repeated. The gases evolved during the digestion and saturation with
ammonia may be conveyed away in any convenient manner; but I will now
describe a special apparatus for that purpose, and constituting another part of
my Invention. The arrangement is shewn in the accompanying Drawing in
section at Fig. 1, and in plan at Fig. 2. In a vessel a of wood, lined with
lead, are pipes 6 projecting through the ends of the said vessel, but closed with
plugs c, so that the pipes may be cleaned out when necessary by removing the
plugs and passing any suitable apparatus through them. Each of the pipes b
is provided with a branch d leading to the digesting vessel, and also with
other branches e, for conveying the products of condensation into a drain.
The branches d are furnished with short pipes f, dipping below the water
line g, so that the gases from the digesting vessel are prevented from passing
out. A stream of water is constantly flowing into the vessel a, and as it rises
to the point h, flows into the branches d and pipes b, mixing with the gases
and facilitating the condensation thereof, but any that remain uncondensed
pass along a passage leading to the sulphur ovens where they become
consumed.
"Having thus described and ascertained the nature of my said Invention, and
the manner in which the same is to be performed, I desire it be understood
that I claim as secured to me under the above in part recited Letters
Patent,-
Firstly, the manufacture of alum by digesting shale, and treating the liquor
with gaseous ammonia simultaneously.
Secondly, the arrangement of. condenser, above described, whether the same
be employed for condensing gases arising from the manufacture of alum,
according to my present improvements, or according to the method described
in the Specification of my former Patent of One thousand eight hundred and
forty-five aforesaid.
In witness whereof, I, the said Peter Spence, have hereunto set my
hand and seal, this Eighteenth day of August, in the year of our Lord
One thousand eight hundred and fifty-nine.
PETER SPENCE. (L.S.)