AN IMPROVED PROCESS FOR TREATING THE SPENT LIME FROM GAS-WORKS TO. REGENERATE THE SAME & TO OBTAIN A PRODUCT FOR USE IN THE MANUFACTURE OF CYANIDES
Year: 1883

page_text: LETTERS PATENT to William Robert Lake of the firm of Haseltine, Lake,
& C° Patent Agents, . Southampton Buildings, London for an Invention of
"AN IMPROVED PROCESS FOR TREATING THE SPENT LIME FROM GAS-WORKS
TO. REGENERATE THE SAME & TO OBTAIN A PRODUCT FOR USE IN THE
MANUFACTURE OF CYANIDES" communicated to him from abroad by August
Theodore Schuessler of Newark, New Jersey and Victor Zeis and Mark D
Hanover both of the City and State of New York all in the United States of
America
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 25th July 1883.
WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake, and Co Patent Agents,
Southampton Buildings, London. "AN IMPROVED PROCESS FOR TREATING THE
"
SPENT LIME FROM GAS-WORKS TO REGENERATE THE SAME & TO OBTAIN A PRODUCT
FOR USE IN THE MANUFACTURE OF CYANIDES [a communication to him from
abroad by August Theodore Schuessler of Newark, New Jersey and Victor Zeis
and Mark D Hanover both of the City and State of New York all in the United
States of America]
The object of this invention is to treat foul lime from gas-works to regenerate
the lime and separate therefrom and utilize the constituents of the impurities; and
it consists in combining the following steps in regular sequence to wit.
First. Leaching with hot water or steam the soluble impurities from the lime.
Second. Treating the liquor containing these impurities in a closed vessel with a
stream of carbonic-acid gas. The sulphureted hydrogen is then passed off to a box
or chamber, where it may be absorbed by the oxide of iron in its hydrated state, or
it may be converted directly into sulphuric acid.
Third. The residual matter in the first chamber, consisting of sulpho-cyanide of
lime, is then decomposed by the addition thereto of the commercial salt of sulphate
of potash. The liquor is then separated from the gypsum or sulphate of lime, and
is evaporated to form a salt for the manufacture of ferro-cyanides

page_text: In carrying my invention into practice I take the spent or foul lime of gas-
works and leach therefrom the impurities by the use of steam or hot water, and
thereby obtain a most concentrated solution of the impurities as well as a thorough
extraction of the same. After the lime has been treated in about four leaching-
vats it will be perfectly deprived of its admixture of foreign substances. It is
then kilned and reburned to be used over again. The mother liquor holding the
sulphurets and sulpho-cyanides in solution is treated in a closed vessel with a
stream of carbonic-acid gas, which liberates an equivalent quantity of sulphuretted
hydrogen. This is passed or led off to a chamber or box and absorbed by oxide of
iron in its hydrated state, or left to be treated in the usual way to obtain its 1
sulphuric acid. The residuum in the first chamber will consist of sulpho-cyanide
of lime, which I decompose by the addition of commercial sulphate of potash.
Gypsum or sulphate of lime is precipitated, from which the liquor is decanted or
separated and evaporated to form the cyanide of potash..
-
By this process I am enabled to economically restore the lime for re-use, and to
obtain the ingredients of the impurities in a commercial form and thereby obviate
the accumulation of waste materials which create a nuisance.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Robert Lake in the Patent Office on the 25th January
1884.
WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake, and Co. Patent Agents,
Southampton Buildings, London, "AN IMPROVED PROCESS FOR TREATING THE
SPENT LIME FROM GAS-WORKS TO REGENERATE THE SAME AND TO OBTAIN A PRODUCT
FOR USE IN THE MANUFACTURE OF CYANIDES."-A communication to mo from
abroad by August Theodore Schuessler, of Newark, New Jersey and Victor Zeis
and Mark D. Hanover, both of the City and State of New York, all in the United
States of America,
The object of this invention is to treat foul lime from gas-works to regenerate
the lime and separate therefrom, and utilize, the constituents of the impurities.
The said invention consists in combining the following steps in regular sequence
that is to say. First. Leaching with hot water or steam the soluble impurities
from the lime. Second. Treating the liquor containing these impurities in a closed
vessel with a stream of carbonic-acid gas. The sulphuretted hydrogen is passed off
to a box or chamber, where it may be absorbed by the oxide of iron in its hydrated
state, or it may be converted directly into sulphuric acid. Third: Decomposing
the residual matter in the first chamber consisting of sulpho-cyanide of lime by the
addition thereto of the commercial salt of sulphate of potash. The liquor is then
separated from the gypsum or sulphate of limo, and is evaporated to form a salt for
the manufacture of ferro-cyanides.
In carrying my invention into practice I take the spent or foul lime of gas-
works and leach therefrom the impurities by the use of steam or hot water, and
thereby obtain a most concentrated solution of the impurities, as well as a thorough
extraction of the same. After the lime has been treated in about four leaching-
vats it will be perfectly deprived of its admixture of foreign substances. It is then
kilned and re-burned to be used again. The mother-liquor holding the sulphurets
and sulpho-cyanides in solution is treated in a closed vessel with a stream of
carbonic-acid gas, which liberates an equivalent quantity of sulphuretted hydrogen.
This is passed or lod off to a chamber or box and absorbed by oxide of iron in its
hydrated state, or left to bo treated in the usual way to obtain its sulphuric acid.
The residuum in the first chamber will consist of sulpho-cyanide of lime, which
I decompose by the addition of commercial sulphate of potash. Gypsum or sulphato
of lime is precipitated, from which the liquor is decanted or separated and evaporated
to form the cyanide of potash.
By this process I am enabled to economically restore the lime for re-use and to
obtain the ingredients of the impurities in a commercial form, and thereby obviate
the accumulation of waste materials which create a nuisance
Having thus fully described the said invention as communicated to me by my
foreign Correspondents and the manner of performing the same, I wish it under-
stood that I claim :-
The method or process herein before described for treating the spent lime from
gas-works for regenerating the same and for obtaining potassium-cyanide, the said
method or process consisting in dissolving and leaching the soluble substances from
the limo; treating the mother liquor thus obtained with a stream of carbonic-acid

page_text: gas, and separating the sulphuretted hydrogen from the same; decomposing the
residuum by adding thereto the commercial salt of sulphate of potash, and then
removing the precipitate, and finally evaporating the moisture, as set forth.
In witness whereof I the said William Robert Lako, have hereunto set my hand
and seal this Twenty fifth day of January in the year of Our Lord One thousand
eight hundred and eighty four.