Improvements relating to the Precipitation of Sewage and Waste Liquids, and the Utilisation of the Products.
Year: 1894

page_text: Date of Application, 9th Nov., 1894
Complete Specification Left, 7th Aug.. 1595-Accepted, 7th Sept., 1895
PROVISIONAL SPECIFICATION.
Improvements relating to the Precipitation of Sewage and Waste
Liquids, and the Utilisation of the Products.
We, WALTER ERNEST ADENEY, Curator, Royal University of Ireland,
Dublin, and of 1 Eaton Place, Monkstown, and WILLIAM KAYE PARRY,
M.A., C.E., and Architect, of 6 Charlemont Terrace, Kingstown, both in the
County of Dublin, do hereby declare the nature of this invention to be as
follows:-
We have described in our Patents Nos. 33120, 18983, 10929º¹, 131549,
improved processes for the treatment of sewage and other like waste liquids.
We have described therein, amongst other things, methods whereby improvements
and economy may be effected in the use of those agents, such as sulphates or
chlorides of aluminium, iron and manganese which may be employed for the
clarification of sewage and other waste liquids.
Now we have made further applications of certain of the principles laid down for
the clarification and purification of sewage and other waste liquids in our Patents,
hereinabove referred to, whereby we effect improvements in methods and economy
in working, not only in the purification of sewage and the like waste liquids; but
also in certain methods employed in other industries. The principles, which we
more particularly refer to here, are those underlying the recovery of the substances
employed in the complete clarification of partially clarified sewage. In our
improved processes described in our said Patents the clarification of sewage and
like waste liquids is effected in two stages, (1) in which the greater part of the
matters in suspension are separated by mechanical subsidence in the first of a series
of four similar tanks of suitable construction (described in our Patent No. 1315493);
(2) in which the sewage, thus partially clarified, is completely clarified by
precipitation in the second of the series of the said four tanks with chloride or
sulphate of alumina, iron or manganese, with the addition of lime if necessary.
Now we have found that by taking advantage of the difference of behaviour
exhibited by the alumina and iron compounds on the one hand, and of the
oxyhydrate of manganese on the other hand, towards dilute sulphuric acid and
dilute hydrochloric acid it is commercially possible to separate manganese from
iron when the same is contained in mixed solutions. It is also possible to employ
a number of substances for precipitating sewage matters in the said tank II in
addition to those ordinarily in use for such purpose. For example the crude
manganous chloride from the chlorine stills in the manufacture of bleaching
powder may be employed for completely clarifying the partially clarified sewage
in the said tank II instead of being treated by one of the methods at present in
use for the recovery of the manganese therein in the form of higher oxides. The
precipitate recovered from tank II then contains the manganese in the form of
oxyhydrate and this may be separated from the other matters in the said
precipitate in the manner to be hereinafter described, and finally obtained in the
form of higher oxide of manganese required by the bleaching powder manufacturer
for the generation of chlorine.
Or again we find that manganiferous iron ores may be heated with sulphuric
acid or fused with bisulphate of soda or potash, or otherwise treated for the
extraction of their iron and manganese in soluble forms and the crude solution

page_text: obtained may be employed in like manner to the crude manganous chloride, for
completely clarifying the partially clarified sewage in the said tank II.
Or again any crude soluble compound of manganese, or of iron and manganese,
or of alumina and manganese however produced may be in like manner
employed.
Whatever substance containing soluble compounds of manganese be employed
for precipitating the partially clarified sewage, or other waste liquid, in the said
tank II, the precipitate or sludge recovered from the said tank II will contain
oxyhydrate of manganese, and, in addition, organic matters and possibly also
compounds of iron and alumina and insoluble inorganic substances.
The said precipitate from the said tank II is treated with dilute sulphuric or
hydrochloric acid, to dissolve out the iron and alumina compounds; the residue
may be separated by mechanical subsidence, or by means of the filter press. The
solution of iron or aluminium compounds obtained, may be employed for the
clarification of fresh quantities of partially clarified sewage in the said tank II.
The after treatment of the residue must be determined by the particular purpose
for which the recovered manganese compounds may be required. For instance
they may be employed by the bleaching powder manufacturer for the generation of
chlorine, or they may be employed by the manufacturer of such compounds of
manganese as pure borates and sulphates, or by the manufacturer of manganates and
permanganates of soda and other bases.
The residue for example may be washed with water, if necessary, to separate
admixed soluble compounds of alumina or of iron and filter pressed if necessary,
dried and ignited gently to burn off the admixed organic matters, the resulting
mass from this treatment will then contain the manganese in the form of higher
oxides, suitable in fact for the generation of chlorine, or for the manufacture of
such compounds as sulphates, borates, manganates, permanganates, and ferro
manganese.
Or the said residue after being washed with water, if necessary, may be exposed
in heaps to the air, to allow the admixed organic matters to ferment. During this
operation the higher oxides of manganese present are reduced and converted to
carbonate of manganese. After this change has been completed the manganous
carbonate may be dissolved out by digestion with dilute sulphuric acid or dilute
hydrochloric acid, or the mass may be gently heated to burn off the humus like
bodies, produced by the fermentation of the organic matters, and to convert the
carbonates to higher oxides of manganese.
Dated this 8th day of November 1894.
W. E. ADENEY.
W. KAYE PARRY.
Improvements relating to the Precipitation of Sewage and Waste
Liquids, and the Utilisation of the Products.
We, WALTER ERNEST ADENEY, Curator, Royal University of Ireland,
Dublin, and of 1 Eaton Place, Monkstown, and WILLIAM KAYE PARRY,
M.A., C.E., and Architect, of 6 Charlemont Terrace, Kingstown, both in the
County of Dublin, 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 :-
We have described in our Patents Nos. 331200, 1898300, 109291 and 13154³³,
improved processes for the treatment of sewage and other like waste liquids.
We have described therein, amongst other things, methods whereby improvements
and economy may be effected in the use of those agents, such as sulphates or

page_text: chlorides of aluminium, iron and manganese, which may be employed for the
clarification of sewage and other waste liquids.
Now we have made further applications of certain of the principles laid down
for the clarification and purification of sewage and other waste liquids in our
Patents herein above referred to, whereby we effect improvements in methods and
economy in working, not only in the purification of sewage and the like waste
liquids, but also in certain methods employed in other industries. The principles,
which we more particularly refer to here, are those underlying the recovery of
the substances employed in the complete clarification of partially clarified sewage.
In our improved processes described in our said Patents the clarification of
sewage and like waste liquids is effected in two stages, (1) in which the greater
part of the matters in suspension are separated by mechanical subsidence in the
first of a series of four similar tanks of suitable construction (described in our
Patent No. 131543), (2) in which the sewage, thus partially clarified, is completely
clarified by precipitation in the second of the series of the said four tanks with
chloride or sulphate of alumina, iron or manganese, with the addition of lime if
necessary.
We have an improved method whereby the carbonates, hydrates and basic
sulphates or chlorides of alumina, iron or manganese, which are co-precipitated
with the sewage solid matters in the said tank II, and which are recovered there-
from, are reconverted into forms suitable for completely clarifying fresh quantities
of partially clarified sewage in the said tank II.
The improved method is as follows:-The precipitate of hydrate, carbonate
and basic sulphates, with organic matters, which results from the said treatment
are deposited at the bottom of the said tank 11 and are drawn up through the
sludge pipe into an iron cylinder, in which a partial vacuum is created, as described
in the said Specification No. 13154. From the cylinder the precipitate is allowed
to flow into a tank of suitable dimensions and material. In this tank when iron
or aluminium compounds have been employed for completely clarifying the sewage,
the precipitate is digested with dilute sulphuric acid (sp. gr. 1-6) or by hydrochloric
acid (sp. gr. 1-12) in quantities just sufficient to completely extract the compounds
of aluminium or of iron in the precipitate. The charge of sludge and acid must be
regulated so that the alumina compounds shall be completely dissolved, and at the
same time no free acid shall remain in the liquid.
After all action has ceased, water is added if necessary, and free acid is tested
for by means of chalk or carbonate of soda, or other carbonate, which when free
acid is present, effervesce giving off carbon dioxide. If free acid be present more
precipitate must be added until all the acid has been completely taken up by the
aluminium or iron compounds in the precipitate.
The digestion with acid may be made at ordinary temperature, but the action
proceeds more rapidly if the mixture of an acid and precipitate be heated gently.
The digestion will be complete in six to twenty four hours according to the
temperature at which it is carried on.
The organic matters originally mixed up with the precipitate separate out after
treatment with acid. They may then be separated from the liquid by filter
pressing, or they may be allowed to subside to the bottom of the tank and then the
liquid syphoned or otherwise drawn off.
If oxyhydrate of manganese be present in the said precipitate or sludge recovered
from tank II, the precipitate must be treated with stronger acid and digested at a
Figher temperature, it it be desired to dissolve out the oxyhydrate contained therein.
In this case sulphuric acid (sp. gr. 1-8) or hydrochloric acid (sp. gr. 1.17) will be
found suitable.
But preferably we take advantage of this difference of behaviour exhibited by
the alumina and iron compound on the one hand, and of the oxyhydrate of man-
ganese on the other hand, towards dilute sulphuric acid and dilute hydrochloric
acid, by se doing it is commercially possible to separate manganese from iron and
alumina, when the same is contained in mixed solutions. It is also possible to employ

page_text: a number of substances for precipitating sewage matters in the said tank II, in
addition to those ordinarily in use for such purpose. For example the crude
manganous chloride from the chlorine stills in the manufacture of bleaching powder
may be employed for completely clarifying the partially clarified sewage in the
said tank II, instead of being treated by one of the methods at present in use for
The precipi-
the recovery of the manganese therein in the form of higher oxides.
tate recovered from tank II then contains the manganese in the form of oxyhydrate
and this may be separated from the other matters in the manner to be hereinafter
described, and finally obtained in the form of higher oxides of manganese required
by the bleaching powder manufacturer for the generation of chlorine.
Or again we find that manganiferous iron ores, or manganiferous waste or bye-
products from metallurgical or chemical manufacturing processes, such for example
as the slag from the Bessemer process of steel making, may be heated with
sulphuric acid, or fused with bisulphate of soda or potash, or otherwise treated
for the extraction of their iron and manganese in soluble form, and the crude
solution obtained may be employed in like manner to the manganous chloride,
for completely clarifying the partially clarified sewage in the said tank 11.
Or again the crude soluble compound of manganese, or of iron and manganese,
cr of alumina and manganese, however produced may be in like manner employed.
Whatever substance containing soluble compounds of manganese be employed
for precipitating partially clarified sewage, or other waste liquid, in the said tank II,
the precipitate or sludge recovered from the said tank II will contain oxyhydrate
of manganese, and in addition organic matters, and possibly also compounds of iron
and alumina and insoluble inorganic substances.
The said precipitate from the said tank II is treated with dilute sulphuric acid
or dilute hydrochloric acid, in the manner hereinabove described, to dissolve out
the iron and alumina compounds, the residue may be separated by mechanical
subsidence or by means of the filter press. The solution of iron or aluminium
compounds obtained, may be employed for the clarification of fresh quantities of
partially clarified sewage in the said tank II. The after treatment of the residue,
insoluble in the dilute sulphuric, or dilute hydrochloric acid, must be determined
by the particular purpose for which the recovered manganese compound may be
required. For instance they may be employed by the bleaching powder manufac-
turer for the generation of chlorine, or they may be employed by the manufacturer
of manganates and permanganates, or by the manufacturer of such compounds, as
pure borates and sulphates.
The said residue for example may be washed with water if necessary to separate
admixed soluble compounds of alumina or of iron, and filter pressed if necessary,
dried and gently ignited to burn off admixed organic matters, the mass resulting
from this treatment will then contain the manganese in the form of higher oxides,
suitable in fact for the generation of chlorine, or for the manufacture of such
compounds as sulphates, borates, mangauates, permanganates and ferro-manganese.
Or the said residue after being washed with water, if necessary, may be exposed
in heaps to the air, to allow the admixed organic matters to ferment. During this
operation the higher oxides of manganese present are reduced and converted into
carbonate of manganese. After this change has been completed the manganous
carbonate may be dissolved out by digestion with dilute sulphuric acid or dilute
hydrochloric acid. Or the mass may be gently heated to burn off the humus like
bodies, produced by the fermentation of the said admixed organic matters, and to
convert the carbonate to higher oxides of manganese.
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 :-
1. The means herein described by which we recover for reuse sulphates or chlorides
of aluminium, irou or manganese which have been employed for the precipitation
of sewage and like waste liquors; that is to say :-the treatment of sludge which

page_text: consists of hydrates, carbonates sulphates and organic matter with sulphuric acid or
with hydrochloric acid in such manner that the bases are again brought into solution
in a condition fit for reuse, whilst the organic matter remains undissolved and may
be separated by deposition or filtration.
2. The means herein described for the treatment of sludge containing aluminium
or iron or both together with manganese and organic matter, whereby the alu-
minium and iron are separated from the manganese and organic matter: that is to
say the treatment of the sludge with dilute sulphuric acid or with hydrochloric
acid applied as herein set forth, so as to dissolve out the aluminium and the iron
leaving the manganese with the organic matter; from which it may afterwards be
readily separated.
3. The employment in the manner described of manganiferous iron ore and
manganese waste and bye-products in the precipitation of sewage and like waste
liquors, together with the recovery of the manganese as a useful product, by the
treatment of the sludge with acid substantially as herein set forth.
W. E. ADENEY.
W. KAYE PARRY.