Improvements In and Apparatus ΤΟΥ Cleaning or Pickling Metals and in Utilizing the Liquids that have been Employed therefor.
Year: 1886

page_text: Date of Application, 24th Dec., 1886.
Complete Left, 15th Sept., 1887.
Complete Accepted, 18th Oct., 1887.
Improvements In and
Apparatus ΤΟΥ Cleaning or Pickling
Metals and in Utilizing the Liquids that have been Employed
therefor.
I ERNEST VLASTO, of 44 Rue des Ecoles, Paris, France, Engineer do hereby
declare the nature of this invention to be as follows:-
In all manufactures in which metals are cleaned or pickled the metallic objects are,
according to the usual practice, immersed in the bath of pure or dilute acid after
which they are rinsed with water. The greater part if not the whole of the water is
run to waste.
Now according to my invention I effect the cleaning or pickling and then the
washing and rinsing with 2 or more waters in the same vessel without removal
therefrom of the metallic objects under treatment. Further the same cleaning or
pickling liquor is sent successively into the different vessels and so are the washing
and rinsing waters; the liquor and the waters gradually become charged or enriched
with the metal which they hold in solution and which can be separated therefrom.
The characteristic feature of the invention is that I supply successively to the vessel
containing a given object to be cleaned or pickled first the acid then the waters for
the first, second and third washings (more or less).
The apparatus for carrying out this process can be constructed in various ways;
I will describe a suitable construction by way of example
There are a number of vessels-say 4 for instance for receiving the metallic objects
to be cleaned or pickled. There is a reservoir for the acid and 3 reservoirs respectively
for the waters for 3 washings (the number of these reservoirs is variable). From the
acid reservoir and the water reservoirs pipes are led to the pickling vessels and for
each of these vessels each pipe has a branch fitted with a cock. Each vessel is also
fitted with a discharge pipe by which it can be emptied by means of ejectors or
exhausters worked by steam or otherwise or the vessels can be emptied by means of
pumps or other suitable apparatus. The discharge pipes carry the liquids up to and
discharge them into channels or gutters which return the liquids to the reservoirs.
The upper part of each discharge pipe is adjustable so as to be capable of discharging
ID 1

page_text: into the channel or gutter leading to the particular reservoir from which the dis-
charged liquid was originally drawn. Or. in some cases it may be practicable to
return the liquid by natural flow. Whatever be the arrangement of the apparatus, it
will be readily understood that as the waters for the first, second and third washings
are employed over and over again instead of being run to waste after each operation,
they become more and more charged with the metal or metals of which the objects to
be cleaned are formed. When the water for the third washings has been used
sufficiently often and has become sufficiently charged it can be used for the second
washings while the water for the second washings can be used for the first, so that
the treatment of the wash waters in order to separate the metals therefrom can
always be applied to the richest waters. When brass articles have been cleaned the
acid bath and the wash waters, suitably concentrated, contain in solution the 2 metals
zinc and copper which can be extracted by treating the liquid with oxide of zinc
obtained in the dry way or by precipitation, and by boiling. The reaction produced
under the action of the oxide of zinc causes the formation of insoluble oxide of copper
which can be separated by filtration; the remaining clear liquid holds the salt of zinc
in solution. Instead of oxide of zinc, carbonate of zinc or even pure zinc can be used
which enables the copper to be separated in the state of carbonate or of metal. By
adding different alkalies such as soda, potass, ammonia, lime, baryta, strontian and
their carbonates and employing the necessary quantity to form oxide of copper, this
metal is precipitated leaving the zinc in solution. The treatment can be carried out
cold but the operation takes more time. When copper and brass are cleaned or
pickled simultaneously the oxide or carbonate of copper obtained from the waters used
for, the brass will serve to saturate the acid waters arising from the cleaning of the
copper.
Dated this 24th day at Dravinban 1986
J. C. MEWBURN,
169, Fleet Street, London,
Agent.

page_text: COMPLETE SPECIFICATION.
Improvements in and in Apparatus for Cleaning or Pickling
Metals and in Utilizing the Liquids that have been Employed
therefor.
I ERNEST VLASTO, of 44 Rue des Ecoles, Paris, France, Engineer, 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 :-
In all manufactures in which metals are cleaned or pickled the metallic objects are,
according to the usual practice, immersed in the bath of pure or dilute acid after
which they are rinsed with water. The greater part if not the whole of the water is
run to waste.
Now, according to my invention, I effect the cleaning or pickling and then the
washing and rinsing with 2 or more waters in the same vessel without removal
therefrom of the metallic objects under treatment. Further the same cleaning or
pickling liquor is sent successively into the different vessels and so are the washing
and rinsing waters, the liquor and the waters gradually become charged or enriched
with the metal which they will hold in solution and which can be separated therefrom.
The characteristic feature of the invention is that I supply successively to the vessel
containing a given object to be cleaned or pickled first the acid, then the waters for
the first, second and third washings (or for a greater or less number of washings).
1
The apparatus for carrying out this process can be constructed in various ways; the
annexed drawing illustrates a suitable construction by way of example:-
--
There are a number of vessels A-say 4 for instance-for receiving the metallic
objects to be cleaned or pickled. There is a reservoir B for the acid and 3 reservoirs
CCC respectively for the waters for 3 washings (the number of these reservoirs is
variable). From the acid reservoir B and the water reservoirs CCC pipes a, a are
led to the pickling vessels A and for each of these vessels each pipe has a branch fitted
with a cock b. Each vessel A is also fitted with a discharge pipe c by which it can be
emptied by means of ejectors or exhausters e worked by steam or otherwise, or the
vessels can be emptied by means of pumps or other suitable apparatus. The discharge
pipes carry the liquids up to and discharge them into channels or gutters D, D¹ D³ ³
which return the liquids to the reservoirs B, C C C³. The upper part of each
discharge pipe c is adjustable so as to be capable of discharging into the channel or
gutter leading to the particular reservoir from which the discharged liquid was
originally drawn. Or, in some cases it may be practicable to return the liquid by
natural flow. Whatever be the arrangement of the apparatus it will be readily
understood that as the waters for the first, second and third washings are employed
over and over again, instead of being run to waste after each operation, they become
more and more charged with the metal or metals of which the objects to be cleaned
are formed.
When the water for the third washings have been used sufficiently often
and has become sufficiently charged it can be used for the second washings while the

page_text: water for the second washings can be used for the first, so that the treatment of the
wash waters in order to separate the metals therefrom can always be applied to
the richest waters. When brass articles have been cleaned the acid bath and the
wash waters, suitably concentrated, contain in solution the 2 metals zinc and. copper
which can be extracted by treating the liquid with oxide of zinc obtained in the
dry way or by precipitation, and by boiling. The reaction produced under the
action of the oxide of zinc causes the formation of insoluble oxide of copper which
can be separated by filtration; the remaining clear liquid holds the salt of zinc in
solution. Instead of oxide of zinc, carbonate of zinc or even pure zinc can be used
which enables the copper to be separated in the state of carbonate or of metal. By
adding different alkalies such as soda, potass, ammonia, lime, baryta, strontian and
their carbonates and employing the necessary quantity to form oxide of copper, this
metal is precipitated leaving the zinc in solution. The treatment can be carried out
cold but the operation takes more time. When copper and brass are cleaned or
pickled simultaneously the oxide or carbonate of copper obtained from the waters
used for the brass will serve to saturate the acid waters arising from the cleaning of
the copper.
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. In the cleaning or pickling of metals, the submitting of the metallic objects to
the action of the acid or pickling liquor and then to washing with one or more
waters in the same vessel without removing the said objects therefrom, the liquor
and the washing waters being used over and over again so that they become
enriched or charged with the metal to such a degree as to be worth treatment for
the recovery of the metal therefrom, substantially as set forth.
2. The construction or arrangement of apparatus substantially as described for
carrying out the pickling and the washing of metallic objects in the same vessel,
the acid or pickling liquor and the washing waters being returned to their respective
reservoirs and used over and over again, as set forth.
3. The utilization of acid liquor and wash waters which have become enriched in
the cleaning or pickling of brass articles, by treating them with reactives so as to
recover the copper therefrom, as set forth.
Dated this 15th day of September 1887.