Improved Preparations for Use as Precipitants in the Treatment of Sewage and other Polluted Water.
Year: 1896

page_text: Date of Application, 25th June, 1896
Complete Specification Left, 24th Mar., 1897-Accepted, 15th May, 1897
PROVISIONAL SPECIFICATION.
Improved Preparations for Use as Precipitants in the Treatment of
Sewage and other Polluted Water.
We ARTHUR ANGELL of the County Laboratory Southampton in the County
of Hants Ph.D., F.I.C. and FRANK CANDY of No. 56 Nightingale Lane Balham
in the County of Surrey Manufacturer do hereby declare the nature of this'
invention to be as follows:-
In the manufacture of precipitants according to our invention we proceed as
hereinafter described.
We take copperas or ferrous sulphate in any other form and add to it a
solution of the following matters namely nitre-cake, nitrate of soda, nitrate of
potash and chloride of sodium To this mixture we add sulphuric acid and
afterwards peroxide of manganese and we then heat the whole until a chlorinated
solution of ferric and other salts is formed.
Or we take ferric sulphate and mix it with a solution of the matters herein before
mentioned namely nitre-cake, nitrate of soda, nitrate of potash and chloride of
sodium and add sulphuric acid to the mixture and thus form a chlorinated solution
of soluble constituents which is suitable for use as a precipitaut either alone or
in admixture with sulphuric acid and bauxite or other like matter containing
alumina in a suitable form.
The proportions required of the several ingredients of the preparations herein-
before described are determined by the character of the sewage or other polluted
water to be treated.
Dated this Twenty-fifth day of June 1896
W. T. WHITEMAN,
Agent for the Applicants.
Improved Preparations for Use as Precipitants in the Treatment of
Sewage and other Polluted Water.
We ARTHUR ANGELL of the County Laboratory Southampton in the County
of Hants Ph.D., F.I.C. and FRANK CANDY of No. 56 Nightingale Laue Balham
in the County of Surrey Manufacturer 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 precipitants according to our invention we proceed as
hereinafter described.
We take copperas or ferrous sulphate in any other form and add to it a solution
of the following matters namely nitre-cake nitrate of soda nitrate of potash and
chloride of sodium. To this mixture we add sulphuric acid and afterwards
peroxide of manganese and we then heat the whole until a chlorinated solution of
ferric and other salts is formed.

page_text: Or we take ferric sulphate and mix it with a solution of the matters hereinbefore-
mentioned namely nitre-cake nitrate of soda nitrate of potash and chloride of
sodium and add sulphuric acid to the mixture and thus form a chlorinated solution.
of soluble constituents.
The said chlorinated solutions are each suitable for use as a precipitant either
alone (ie. without addition of other matters) or in admixture with bauxite or other
mineral containing alumina in a suitable form such as calcined clay and with
addition of sulphuric acid.
Where the precipitant is not required to have high antiseptic properties the
peroxide of manganese and chloride of sodium and nitrate of soda and nitrate of
potash or any one or more of them may be dispensed with.
We have prepared a chlorinated solution suitable for use according to our
invention by mixing together two parts by weight of a saturated solution of
copperas and one part by weight of chloride of sodium and two parts by weight of
sulphuric acid of the specific gravity of commercial oil of vitriol and one part by
weight of nitre cake containing about ten to fifteen per cent. of available acid and
heating the mixture to about boiling point and then adding thereto and stirring in
from one to two parts by weight of peroxide of manganese. It is however not
necessary that the materials be used in exactly these proportions or that the
modus operandi we have described be exactly followed as both may be varied to
some extent without materially affecting the result. Moreover the proportions of
the materials or some of them must be to some extent determined by the character
of the sewage or other polluted water to be operated on.
In preparing the mixture of chlorinated solution and bauxite we grind the
bauxite with the solution and with sufficient sulphuric acid to render all or nearly
all the alumina available the proportions being dependent on the proportions of the
constituents of the bauxite and the strength of the acid. As an example if the
bauxite contain from 48 to 50 per cent. of available alumina and if the acid be of
the specific gravity of commercial oil of vitriol (namely from 148 to 150 degrees
Twaddell) the required proportion of acid relatively to the bauxite will be about
140 parts by weight of the acid to 100 parts by weight of bauxite.
Where the matter to be treated with the precipitant or the effect required to be
produced by the precipitant admits of the peroxide of manganese being dispensed
with the precipitant may be conveniently prepared by placing in the required
proportions in an edge runner mill ferric sulphate and nitre-cake and sulphuric
acid and bauxite or other mineral containing alumina in a suitable form and
grinding the whole together with sufficient water to produce a semi-fluid mixture.
In any case after being prepared as herein before described the precipitant
containing salts of alumina may be at once added to the liquid to be treated or it
may be run into convenient receptacles and be allowed to set or become solid
therein in which latter case the precipitant must be dissolved in water or in the
liquid to be treated and well mixed therewith on use.
The nitre cake is used as an economical source of sulphuric acid and sulphate of
soda or sulphate of potash therefore the use of sulphuric acid in addition to the
nitre-cake is dependent on the quantity of nitre-cake which it is practicable to use
and the proportion of acid contained therein which proportion varies considerably
in different samples of the nitre-cake. Consequently in order to determine what
quantity of sulphuric acid if any) is required in any particular case it is necessary
to ascertain the quantity of available sulphuric acid present in the nitre-cake to be
used and the quantity of acid which in conjunction with the water to be added will
suffice to render soluble the alumina in the bauxite. The factor limiting
practicability of use of large quantities of nitre-cake is the quantity of sulphate
of soda which it is admissible to introduce into the sewage to be treated. Where
the sewage is of such a character that considerable quantities of sulphate of soda
are not objectionable as for instance where the sewage contains much dye liquor or
wool scourers refuse it is practicable to use such a quantity of nitre-cake that the
amount of sulphuric acid contained therein is sufficient to render soluble all the

page_text: available alumina in the bauxite or other aluminous mineral selected for use in
which case addition of sulphuric acid is of course not required.
Having now particularly described and ascertained the nature of our said inven--
tion and in what manner the same is to be performed we declare that what we
claim is :-
. The manufacture substantially as hereinbefore described of a precipitant the
essential characteristic of which is the presence therein of soluble salts of alumina.
and soluble salts of iron in considerable proportions in conjunction with sulphate of.
soda or sulphate of potash derived from nitre-cake.
wth dow of March 1897
W. T. WHITEMAN,
Agent for the Applicants..