Year: 1886

page_text: Date of Application, 16th Mar., 1886.
Complete Left, 16th Dec., 1886.
Complete Accepted, 18th Jan., 1887.
We, CHARLES WILLIAM BURTON, of Nogent, Builder and FRANCOIS THEOPHILE
MOISON, of Mouy, Gentleman both in France do hereby declare the nature of this
invention to be as follows:-
This invention relates to substances for the purification of water, which substances
possess the following advantages that is to say, the cost of manufacture is low and
they do not leave in the water any deleterious substance.
We will successively consider the case of the purification of waters charged either
with carbonates or magnesia or with the said carbonates and with sulphates of lime,
and we will indicate for these various conditions the substances which we employ for
precipitating these impurities.
Dolomite calcined to two different degrees and prepared according to requirements,
offers great advantages over soda as when it is completely decarbonated, it precipi-
tates carbonates of lime and of magnesia. The lime which it contains acts first upon
a portion of the bicarbonates and the magnesia completes the precipitation.
If the water contains a little sulphate of lime, the carbonate of magnesium formed
by the precipitation of the bicarbonate of lime decomposes in its turn the sulphate of
lime, the lime of which is precipitated in the form of carbonate.
When the dolomite is heated to a temperature which does not surpass cherry-red,
the decomposition of the carbonate of magnesium only is effected. The product
of the calcination is a mixture of carbonate of lime and of oxide of magnesium, or
magnesia, which in the purification of water, advantageously replaces the lime and
caustic soda.
•
The magnesia, which dissolves with difficulty, constituting solely the excess of the
reagent, presents little inconvenience. When the sulphate of lime is to be precipitated
alone, we employ dolomite carbonated in the air. The product of the calcination is
exposed to the action of the air; it absorbs carbonic acid, and the magnesia becomes
again carbonated, but in a different state from its natural one. It generally happens
that water contains bicarbonates and sulphate of lime; in this case we employ a
proportioned mixture of these reagents according to the composition of the water
to be purified.

page_text: When it is necessary to remove from the water sulphates and their bases by the aid
of carbonate and oxalate of baryta, either alone or inixed together or even with the
other reagents, it is often sufficient to agitate the water with the reagents or to let it
pass through a layer thereof for obtaining its purification. All these reagents can also
antitartar
be employed in the same manner as the commercial products called
(antitartres).
22
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicants.

page_text: Improvements relating to the Purification of Water.
We, CHARLES WILLIAM BURTON, of Nogent, Builder, and FRANCOIS THEOPHILE
MOISON, of Mouy, Proprietor, both in France, 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 the application of dolomite, or carbonate or oxalate of
baryta, for the purification of water, which substances possess the following advantages,
that is to say, their cost is low and they do not leave in the water any deleterious
substance.
We will successively consider the cases of the purification of water charged either
with carbonates or magnesia; and with the said carbonates or sulphate of lime; and
we will indicate for these various conditions the substances which we employ for
precipitating these impurities.
If dolomite, which offers great advantages over soda, is calcined to two different
degrees, say to a light red and white heat respectively, two different products are
obtained, viz. a mixture of calcined magnesia and carbonate of lime in the first case,
and a mixture of caustic lime and magnesia in the second case.
We also obtain a third product by exposing the two products above described to
the action of tho air. When thus exposed the said products absorb the carbonic acid
of the air, and return again to the condition of carbonates but in a different molecular
condition, the substance being no longer dolomite, but a mixture of carbonate of lime
and carbonate of magnesia.
When the dolomite is completely decarbonated, as in the second case just referred
to, it precipitates carbonates of lime and of magnesia. The said product can be used
in excess without danger, if the necessary quantity of the third product is added to the
water to be purified. The lime which the product contains acts first upon a portion
of the bicarbonates, and the magnesia completes the precipitation.
If the water contains a little sulphate of lime, the carbonate of magnesium formed
by the precipitation of the bicarbonate of lime decomposes in its turn the sulphate of
lime, the lime of which is precipitated in the form of carbonate.
When the dolomite is heated to a temperature which does not surpass cherry-red,
as in the first case, the product of calcination, which is a mixture of carbonate of lime
and oxide of magnesium or magnesia, advantageously replaces the lime and the caustic
soda in the purification of water.
The magnesia which dissolves with difficulty, constituting solely the excess of the
reagent, presents little inconvenience.
When the sulphate of lime is to be precipitated alone, we employ dolomite carbonated
in the air as herein before described.
It generally happens that water contains bicarbonates and sulphate of lime ; in this
case we employ a proportioned mixture of the reagents according to the composition
of the water to be purified.
When it is necessary to remove from water sulphates and their bases by the aid of

page_text: carbonate and oxalate of baryta, either alone or mixed together, or even with the other
reagents, it is often sufficient to agitate the water with the reagents, or to let it pass
through a layer thereof for obtaining its purification.
All the said reagents can be employed in the same manner as the commercial
products called "antitartres."
Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed we declare that what we claim is
The application, to the purification of water, of calcined and prepared dolomite and
of carbonate and oxalate of baryta in the above described manner.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicants.