Improvements in the Method of and Means for Purifying Waste and Impure Waters, particularly such Waters as Contain Greasy Matters.
Year: 1899

page_text: Date of Application, 10th Jan., 1899
Complete Specification Left, 10th Oct., 1899-Accepted, 25th Nov., 1899
PROVISIONAL SPECIFICATION.
Improvements in the Method of and Means for Purifying Waste and
Impure Waters, particularly such Waters as Contain Greasy
Matters.
I, JULES DELATTRE, of Dorignies-Flers (Nord), in the Republic of France,
Spinner, do hereby declare the nature of this invention to be as follows:-
My invention relates to improvements in the method of and means for purity-
ing waste and impure waters particularly auch waters as contain greasy matters,
like the residual water from wool scouring and other industrial processes.
My invention can also be available for purifying water in rivers and streams,
which contains only a small quantity of greasy matters; it is in fact impossible
to purify such water by means of the ordinary processes which are made in-
efficient on account of said proportion, however small it may be, of greasy
matters.
My invention can finally be applied for purifying water containing no greasy
matters at all, the operating relating to the extraction of these matters being
in that case done away with.
The improvements consist mainly in treating the impure water with sulphuric
acid, depositing the precipitated impurities, and decanting the acid liquid which,
neutralized by the addition of lime produces a second deposit which is brought
in the filter presses into a state of cakes and the neutral or slightly alkaline
liquid is discharged into the river or other outfall.
The first deposit is treated by a volatile solvent of grease which eliminates
or extracts the greasy matter, the residue being brought into a state of cakes in
filter presses. The grease is then separated and the volatile solvent recovered
by distillation in any suitable form of still.
The impure water is preferably pumped to a suitable elevation to enable it to
be run through the apparatus and treated continuously in one operation until
the purified effluent flows into the river or other outfall.
The sulphuric acid is supplied to the liquid through perforated pipes or plates
or equivalent devices and further a mechanical agitator is also preferably employed
to insure a thorough mixture with the acid before the liquid enters the first
series of settling tanks where the greasy matters are deposited.
Instead of sulphuric acid any other suitable acid or chemical equivalent
may be employed which will effect the same result.
The water is admitted to the first settling tank as a sheet which overflows along
the total width of the tank. Owing to the considerable width of the sheet of
water the speed is very slow so that the deposit is left for the greater part in
the first tank; the water then overflows in the next tank, and so on, issuing from
the last tank nearly clear but slightly acidulated; but to remove any particles
remaining in suspension it is passed through a suitable filter.
After leaving the filter the water is run through a channel where it is mixed
with milk of lime, supplied from suitable containers, in order to neutralize the
alight acidity, and then passed through a further series of settling tanks to
receive the deposited precipitate, the effluent flowing pure and neutral into the
river or other outfall."

page_text: If necessary the effluent may be aerated by a current of air before being
discharged.
The sludge from the first series of settling tanks is pumped into an extracting
battery where it is treated by a suitable volatile solvent to recover the grease in
the liquid sludge. The volatile solvent saturated with grease is then distilled
and separated from the grease which is thus recovered.
In order to obtain in the extracting batteries a more effective working and
to diminish the number of these batteries, instead of sending directly the greasy
earthy matters from the settling tanks into the extracting battery it is advisable
to send them first into a mixing apparatus where they are mixed with the
solvent. When the mixing is accomplished, after a short rest, a large quantity
of the water separates from the greasy matters; it is then drawn off from the
lower part of the mixing apparatus and sent back to the settling tanks containing
acidulated waters. What remains in the mixing apparatus is then sent into the
extracting battery.
When the quantity of water to be treated varies greatly from time to time,
instead of having only one plant it is advisable to erect several identical plants
side by side a smaller or greater number of these plants being then worked
according to the quantity of water to be treated.
Dated this 9th day of January 1899.
Improvements in the Method of and Means for Purifying Waste and
Impure Waters, particularly such Waters as Contain Greasy
Matters.
I, JULES DELATTRE, of Dorignies-Flers (Nord), in the Republic of France,
Spinner, 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:-
My invention relates to improvements in the method of and means for purify-
ing waste and impure waters particularly such waters as contain greasy matters,
like the residual water from wool scouring and other industrial processes.
My invention can also be available for purifying water in rivers and streams,
which contains only a small quantity of greasy matters; it is in fact impossible
to purify such water by means of the ordinary processes which are made in-
efficient on account of said proportion, however small it may be, of greasy
matters.
My invention can finally be applied for purifying water containing no greasy
matters at all, the operations relating to the extraction of the matters being
in that case donę away with.
The improvements consist mainly in treating the impure water with sulphuric
acid, depositing the precipitated impurities, and decanting the acid liquid which,
neutralised by the addition of lime produces a second deposit which is brought
in the filter pressos into a state of cakes and the neutral or slightly alkaline
liquid is discharged into the river or other outfall.
The first deposit is treated by a volatile solvent of grease which eliminates
or extracts the greasy matter, the residue being brought into a state of cakes in
filter presses. The grease is then separated and the volatile solvent, recovered
by distillation in any suitable form of still.
Instead of sulphuric acid any other suitable acid or chemical equivalent
may be employed which will effect the same result.

page_text: In the accompanying two sheets of drawings-
Fig. 1 is a side elevation partly in section of a plant adapted for purifying
waste and impure waters, particularly such waters as contain greasy matters
and Fig. 2 is a plan view of Fig. 1 shown also partly in section. Fig. 3 is a
plan view of several identical plants built side by side for convenience when
the quantity of water to be treated varies greatly from time to time.
In carrying out my invention the water is directed to a channel a by a pump b
In the first place, said pump causes a head of liquid which permits an overflow
of a speed corresponding to the requirements during the whole process.
In the second place, said pump ensures a regular feeding of the water to be
treated so as to obtain an economical and perfect working, specially as far as the
acidifying is concerned.
As soon as it leaves the pump, the foul water is mixed in the channel with a
certain amount of sulphuric acid supplied by the tanks c; this acid must reach
the water in a well divided state which can be obtained for instance by means of
perforated lead plates or pipes, so as to ensure a perfect mixture.
Besides, in order to complete the mixture, the water arrives downwards in a
cylindrical receiver d where it is stirred by the agitator e; it leaves the tank at
the bottom and ascends in a vertical conduit wherefrom it overflows in a
channel g.
From this channel g, the acidified water passes into settling tanks such as 1,
2, 3, 4, 5, 6 where it settles which facilitates the deposit of all the precipitated
matters which draw with them the fatty acids which have been set free.
The acidified water is admitted in the first settling tank as a sheet which over-
flows along the total width of the tank. Owing to the considerable width of the
sheet of water the speed is very slow, so that the deposit is left for the greater
part in the first tank; the water then overflows in the next tank and so on, issuing
from the last tank nearly clear but slightly acidulated.
The working of the tanks is methodical that is to say, each of them serves
successively as first or receiving tank for the acidified water. For this purpose,
the tanks are arranged in the following manner. The walls or partitions between
them are provided at the top with grooves in which can be inserted removable
planks of about two thirds of a foot high which act as overfalls. The channel y
is formed along one edge of the tanks and is provided, in front of the partitions,
with gates g¹, 92, 9³. A delivery or exit channel is formed along the opposite
edge of the tanks and is also provided with gates 1, 3, in front of the partitions.
When it is desired to introduce water in the tank 1 and deliver it at the end
of tank 5, the overfalls h are placed as shown in Figs. 1 and 2, i.e., at the inlet
of the tank 1 and at the outlet of the tank 5 and the gates gl and are raised.
The water then circulates as indicated by the arrows and the sludge and greasy
matters settle in the tanks 1, 2, 3, 4, and 5.
Meanwhile, the sludge which had previously accumulated in the tank 6
descends into the well through the channel, the gate us being open.
When the tank 1 is sufficiently filled with greasy matters, it is isolated in`
order to evacuate the same into the well through the gate ¹ and the channel ",
and the tank 6 serves as the last settling tank.
For this purpose, the gates us, g¹, j³ are closed and planks such as h are intro-
duced into the grooves in the partition between tanks 1 and 2, the plank on the
side of tank 1 being a little higher than the plank on the side of tank 2; besides,
the planks between tanks 5 and 6 are taken away and one tank is placed on
the left wall of tank 6. If the gates g³, 1, are then opened, the water arrives
to the tank 2 and is delivered at the outlet of tank 6, and so on, the overfalls
being always placed at the inlet of the first tank in work and at the outlet of
the last tank, and the overfalls of the intermediate tanks being taken away on
order to allow the water to pass freely from one tank to another.
As when leaving the last tank the water draws yet along some light particles,
it passes through a filter i which is constituted simply by placing wood fibres

page_text: or any other suitable filtering material in the channel formed between the
planks h, as clearly shown in Fig. 2.
When leaving the filter i, the water passes in the channel j, where it receives
a milk of lime which is supplied from the cisterns k; the water then passes into
a stirring apparatus and then in a series of tanks such as 7, 8, 9, 10, 11, and 12
disposed exactly like the aforementioned tanks. This milk of lime is intended
to neutralise the acidulated waters before sending them to the river. As the
acidity is very weak, the quantity of lime will be very small and the deposit will
be little important. Accordingly the neutralising tanks will be less in number
than the acidifying tanks.
Said neutralising tanks work exactly like the acidifying tanks with the same over-
flows and filter at the outlet, and the mixing of the water with the milk of lime
is made exactly like the mixing with the acid, but wood or other suitable pipes
are substituted for lead pipes.
From said tanks, the water is sent to the river completely purified and
neutralised.
The number of acidifying and neutralising tanks may vary according to
circumstances.
The deposits of acid sludge, evacuated as aforesaid into the well & are sent by
means of a pump v into an extracting battery m m where the grease is methodically
taken off by means of a current of benzin. Bisulphide of carbon, alcohol, ether,
oil of turpentine or any other solvent of greasy matters may be used.
It is to be remarked that in the extracting battery the recovery of grease is
effected upon liquid sludge and not upon greasy earthy matters previously pressed
and dried.
When the sludge is deprived of benzin, it is sent into a tank whence, by
means of a pump 2, it is passed through filter presses where it is formed into
cakes, which constitute an excellent manure.
The benzin saturated with grease is passed through a distilling apparatus r
where it separates from the recuperated fatty matters.
In order to obtain in the extracting battery a more effective working and to
diminish the size of this battery instead of sending directly the greasy earthy
matters from the settling tanks 1, 2, 3, in the extracting battery m m it is
advisable to send them first into a mixing apparatus where they are mixed
with the solvent. When the mixing is accomplished, after a short rest, a large
quantity of the water separates from the greasy matters; it is then drawn off
from the lower part of the mixing apparatus. What remains in the mixing
apparatus is then sent to the extracting battery m m.
The sludge deposited in the neutralising tanks is evacuated in a well y exactly
like the acid sludge is sent into the well . The sludge is taken in the well y
by means of a pump z which passes it through a battery of filter presses y¹ where
it is formed into cakes, which can be used as manure.
When the quantity of water to be treated varies greatly from time to time,
instead of having only one plant it is advisable to erect several identical plants
side by side (Fig. 3), a smaller or greater number of these plants being then
worked according to the quantity of water to be treated.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:-
1. For carrying out the herein described process for purifying impure waters
an installation such as that described and illustrated and consisting of-
(1). A pump for raising the impure water into a higher channel where it
is charged with sulphuric acid or other equivalent re-agent,-
(2), A mechanical agitator for insuring a thorough intermixture of the
re-agent and the water,-
(3). A series of settling tanks to receive the precipitate and for decanting
the acid liquid,—

page_text: (4). A filter at the outlet of the last tank,-
(5). A channel where the water issuing from the filter receives a supply of
milk of lime,
(6). A mechanical agitator for insuring a thorough intermixture of the lime
with the water,―
(3). A series of neutralising tanks and an extracting battery for the degreasing
of fatty matters deposited after the acid treatment.
2. In an installation of the kind specified in Claim 1, the construction and
arrangement of the settling tanks for the treatment of the impure water with
chemical re-agents, the deposition of the precipitate and impurities, and the
decanting of the greater part of the water substantially as and for the purposes
described.
3. The general combination and arrangement of parts substantially as herein
described and illustrated and constituting an installation for carrying out the
herein described process of purifying impure waters.
Dated th:. 04h 1- af Ondakan 1900
H. B. BARLOW & GILLETT,
Agents for Applicants, 17, St. Ann's Square, Manchester.