Improvements in the Method of Purifying Sewage by Means of Lime in conjunction with a Salt of Iron.
Year: 1892

page_text: Date of Application, 10th Feb., 1892
Complete Specification Left, 10th Nov., 1892-Accepted, 4th Feb., 1893
PROVISIONAL SPECIFICATION.
Improvements in the Method of Purifying Sewage by Means of Lime
in conjunction with a Salt of Iron.
I HAMOR LOCKWOOD of 7 Chapel Walks Cross Street, Manchester Manu-
facturing Chemist do hereby declare the nature of this invention to be as
follows:-
If sewage containing dye stuffs, organic coloring matters or other organic
impurities be taken and to it be added a soluble salt of iron such as a sulphate of
iron and to this be added lime preferably in the form of milk of lime a precipitation
takes place of the albuminoids, iron colouring matters and other impurities in it
which on settling leave a resulting effluent more or less purified. In practice this
precipitation takes more or less time and my invention is the heating the milk of
lime by means of superheated steam or by other convenient method before its
addition to the sewage whereby precipitation takes place practically instantaneously
and the value of the process is thereby much enhanced. Therefore my process is the
artificial heating of the milk of lime as aforesaid.
COMPLETE SPECIFICATION.
Improvements in the Method of Purifying Sewage by Means of Lime
in conjunction with a Salt of Iron.
I, HAMOR LOCKWOOD, of 7, Chapel Walks, Cross Street, Manchester,
Manufacturing Chemist, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement :-
If sewage containing dye stuffs, organic colouring matters, or other organic
impurities, be taken, and to it be added a soluble salt of iron, such as sulphate of
iron, and to this be subsequently added lime, say, in the form of milk of lime, a
precipitation takes place in the albuminoids, and, colouring matters, and other
impurities in it, which, on settling, leave a resulting effluent more or less purified.
In practice this precipitation takes more or less time, but according to invention
my i
milk of lime is added to the sewage in a heated condition, say at about
160° Fahrenheit or upwards (the heating being effected by means of superheated
steam or by other convenient methods before its addition to the sewage), whereby
precipitation takes place practically instantaneously, and the value of the process is
thereby enhanced.
As regards the proportions of iron salt and lime used, these may be governed by
the directions specified in the Specification of my former application for Patent
No. 19395 of 1891.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The purification of sewage by a soluble salt of iron and the subsequent addition

page_text: thereto of milk of lime in a heated state whereby precipitation is rendered
practically instantaneous; substantially as described.
Dated this 7th day of November 1892.
CHEESBROUGH & ROYSTON, Fels. Chart. Inst. P.A.,
15, Water Street, Liverpool, Applicant's Patent Agents.