Improvements in the Treatment of Sewage.
Year: 1894

page_text: Date of Application, 1st Aug., 1894
Complete Specification Left, 1st May, 1895-Accepted, 1st Aug., 1895
TRUVIDIONAL DI MOTIVATION.
Improvements in the Treatment of Sewage.
I, HENRY LIVINGSTONE SULMAN of 60 Gracechurch Street, in the City of
London, Analytical Chemist, do hereby declare the nature of this invention to be
as follows:-
This invention relates to a process for sterilising sewage, precipitating the foecal
matter and allowing the effluent water to pass away in a clear condition. The
agent I prefer to employ to effect this purpose is soap which may be manufactured
from any of the greases fats fatty acids and oils known and used for such purposes
with potash, soda, or ammonia as base. The soap may be applied to the sewage in
a dissolved or fluid condition and a coagulum or precipitate is then formed by the
addition of a solution or suspension in water of lime, alum, magnesia, or other
metallic salts.
Not only does the coagulum contain the foecal matters but it also draws with it
bacteria and other suspended impurities thus leaving the effluent water in a com-
paratively clear condition. In ordinary sewage the effluent waters contain immense
quantities of bacteria which are too small to be retained in filters, but the molecules
of soluble soap permeating the whole sewage being more minute than the bacteria
the latter are drawn with the coagulum of insoluble soap formed when lime or other
suitable agent is added.
In case the coagulum should be of less specific gravity than the water and thus
be prevented from precipitating I may add some inert substance of greater specific
gravity than water to the sewage such for instance as earth, spent ore or any other
inert and heavy suitable substance by which means the coagulum will be weighted
and made to subside from the now clarified effluent.
Dated this 1st day of August 1894.
W. P. THOMPSON & BOULT,
Agents for the Applicant.
1, HENRY LIVINGSTONE SULMAN, of 60 Gracechurch Street, in the City of
London, Analytical Chemist, 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 and by the following statement :-
This invention relates to a process for sterilising sewage, precipitating the foecal
matter and allowing the effluent water to pass away in a clear condition. The
agent I prefer to employ to effect this purpose is soap which may be manufactured
from any of the greases, fats, fatty acids, and oils known and used for such purposes,
with potash, soda, or ammonia as base. The soap may be applied to the sewage in
a dissolved or fluid condition and a coagulum or precipitate is then formed by the
addition of a solution or suspension in water of lime, alum, magnesia, or other
metallic salts, such as ferrous and ferric salts etc.

page_text: Not only does the coagulum contain the foecal matters but it also draws with it
bacteria and other suspended impurities thus leaving the effluent water in a com-
paratively clear condition. In ordinary sewage the effluent waters contain immense
quantities of bacteria which are too small to be retained in filters, but the molecules
of soluble soap permeating the whole sewage being more minute than the bacteria
the latter are drawn with the coagulum of insoluble soap formed when lime or other
suitable agent is added.
In case the coagulum should be of less specific gravity than the water and thus
be prevented from precipitating I may add some inert substance of greater specific
gravity than water to the sewage such for instance as earth, spent ore or other inert
and heavy suitable substance by which means the coagulum will be weighted and
made to precipitate from the effluent.
The proportions of soap to sewage may vary according to the amount of foecal
matter in suspension-but I have obtained good results by employing from 1 to 3 lbs.
of soap per ton of sewage effluent though smaller quantities have been successfully
used in some cases. I do not therefore confine myself to these proportions which
may be increased or diminished as required the above quantities being given merely
as examples of the mode in which I carry out the invention.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The employment of soap in the treatment of sewage.
2. The employment in the treatment of sewage of soap with a precipitant.
3. In the treatment of sewage the formation of a coagulum substantially as
described which precipitates the foecal matter taking with it bacteria and other
suspended impurities leaving the effluent water comparatively clear.
Dated this 1st day of May 1895.
BOULT & WADE,
Agents for the Applicant.