Improvements in or connected with the Manufacture of Bleaching Powder.
Year: 1893

page_text: Date of Application, 29th Dec., 1893
Complete Specification Left, 26th Sept., 1894-Accepted, 27th Oct., 1894
PROVISIONAL SPECIFICATION.
Improvements in or connected with the Manufacture of Bleaching
Powder.
WC HOLBROOK GASKELL Junior of Clayton Lodge Aiglruth Liverpool,
Manufacturing Chemist VERO CHARLES DRIFFIELD of Cliff House Appleton
Widnes Engineer ARTHUR CAREY of Browside Gateacre Liverpool Analytical
Chemist and FREDERICK WILLIAM WRIGHT of 18 Chester Street, Widues,
Chemist all in the County of Lancaster do hereby declare the nature of this
invention to be as follows:-
In the manufacture of bleaching powder from chlorine gas, which is largely
diluted with other gases, large surfaces of lime have to be exposed to the gas in
order to absorb it.
•
We have found that the chambers in which the exposure takes place are apt to
become too warm and that it is necessary to cool the gases after a certain amount
of chlorine gas has been absorbed. Apparatus for this purpose forms the subject
matter of an application for Letters Patent No. 1214 of the 19th January 1893.
It has been found that when chlorine gas cooled by means of the said apparatus is
brought into contact with comparatively cool lime or with partly finished bleaching
powder, moisture is apt to condense upon the surface of the lime and more
especially on the partly made bleaching powder and that the surface is thereby
rendered less porous, sq, that the chlorine gas does not readily penetrate and
frequently bleaching powder is spoilt.
The present invention has for its object to remedy this defect and consists in
drying the chlorine gas which issues damp from a warm compartment of the
bleaching powder chambers before passing it through the aforesaid cooling
apparatus.
The gas may be dried by passing it up through a tower containing some such
material as coke or flint down which strong sulphuric acid is run, or by contact
with calcium chlorate or other sufficiently hygroscopic substance.
Dated this 30th day of Danambor 1902
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with the Manufacture of Bleaching
Powder.
We HOLBROOK GASKELL Junior of Clayton Lodge Aiglruth, Liverpool,
Manufacturing Chemist, VERO CHARLES DRIFFIELD of Cliff House, Appleton,
Widnes, Engineer, ARTHUR CAREY of Browside, Gateacre, Liverpool, Analytical
Chemist and FREDERICK WILLIAM WRIGHT of 18 Chester Street, Widnes,
Chemist, all in the County of Lancaster, do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in aud by the following statement :-
In the manufacture of bleaching powder from chlorine gas which is largely
diluted with other gases, large surfaces of lime have to be exposed to the gas in
order to absorb the chlorine.

page_text: We have found that the chambers in which the exposure and absorption takes
place are apt to become too warm and that it is necessary to cool the gases after a
certain amount of chlorine gas has been absorbed. Apparatus for this purpose
forms the subject matter of Letters Patent No. 1214 of the 19th January 1893.
It has been found that when chlorine gas cooled by means of the said apparatus is
brought into contact with comparatively cool lime or with partly finished bleaching
powder, moisture is apt to condense upon the surface of the lime, and more
especially on the partly made bleaching powder and that in consequence the
bleaching powder is frequently spoilt.
The present invention has for its object to remedy this defect and consists in
drying the chlorine gas which issues damp from a warm compartment of the
bleaching powder chamber before passing it through the aforesaid cooling
apparatus.
The gas may be dried by passing it up through a tower containing some such
material as coke or flint down which strong sulphuric acid is run, or by contact
with calcium chloride or other sufficiently hygroscopic substance.
The accompanying diagram shews an arrangement of apparatus for effecting the
drying according to this invention but we do not limit ourselves to the precise
arrangement shewn:
A and A' are two absorption compartiments of a bleaching powder chamber.
B is the pipe which conveys the gas from the compartment A to the drying
tower. C which contains coke, flints, or such like material down which flows strong
sulphuric acid, which may be introduced at the lutes D, the said acid meeting the
gas and depriving it of watery vapour. After thus being dried the gas passes by
the pipe E when it may be conveyed direct into the compartment A', but we
prefer to cool it as well in which case it is conveyed into the cooling chamber F
and from thence into the compartment A' by the pipe G. The cooling chamber is
shewn as being cooled by means of a coil H through which water or other cooling
medium circulates.
We have described the drying as being effected before the cooling although of
course the drying could be effected after the cooling but it is best to do the drying
first and the cooling after because the absorption of the moisture by the hygroscopic
substance such as sulphuric acid generates heat and if the drying be effected after
cooling this heat is not removed.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed we declare that what we
claim is.-
1. In the manufacture of bleaching powder in successive absorption compartments
the drying or removal of the vapour of water from the gas issuing from one
compartment, before the gas enters a succeeding compartment substantially as and
for the purpose hereinbefore described.
2. In the manufacture of bleaching powder in successive absorption compartments
the drying or removal of the vapour of water from, and the cooling of the gas
issuing from one compartment before the gas enters a succeeding compartment
substantially as and for the purpose herein before described.
Dated this 26th day of September 1894.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, Agents.