Apparatus to be Employed therefor.
Year: 1885

page_text: Apparatus to be Employed therefor.
I, EDWARD VINCENT GARDNER, of Berners College, Berners Street, in the Parish
of Marylebone, in the county of Middlesex, Professor of Chemistry, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE MANUFAC-
TURE OF WHITE LEAD AND IN APPARATUS TO BE EMPLOYED THEREFOR," to be as
follows:-
This Invention relates to improvements, first, in apparatus for-melting the lead to
be converted into white lead; secondly, in the gases and vapours admitted to the
converting chamber; thirdly, in the method of, and apparatus for, supplying the
vapours and gases, necessary for the process of conversion to the converting
chamber; fourthly, in the arrangement of troughs and materials within the con-
verting chamber in order to preserve the contents thereof in a proper saturated
condition; and, lastly, in an improved apparatus for drying the white lead after
the process of conversion.
In the following description of this invention reference is made to the accom-
panying drawings.
The apparatus, for melting the lead to be converted into white lead, constituting
the first part of this invention is constructed and arranged as follows:-
Figure 1. is a sectional view of the apparatus. The furnace E. is enclosed in
order to prevent the escape of any noxious gases or vapours. A. and B. are two
cast iron pots which are united at their lower parts by the channel pipe C. and at
their upper parts by the connecting piece or cover D. These pots are set in brick-
work in such a manner that the products of combustion passing into the space F.
can play round the pot A. and against one side of the pot B. The walls G. G.
enclose a chamber G within which is the pot A. a chimney I. leads from the upper
part of this chamber. Any portion of the top of the pot B., which is within the
chamber G¹, is closed. The heated products of combustion after heating the pots
flow upwards through openings in the cover of the heating space F. which cover is
on a level with the top of the pots, into the before mentioned chamber, and are
thereby brought into contact with the surfaces of the melting metal in the pot A.
and tend to prevent the oxidation of the same, a disadvantageous result which
would occur if air alone were allowed to come into contact with the metal. The
D1

page_text: lead to be melted is placed into the pot A. through a door H. at one side of the
chamber G¹ and, when melted, it runs, free from dross and scoriæ, through the
channel pipe C., into the pot B. The dross and scoriæ is removed, as desired, from
the pot A. through the door H. The pot B. is partially set solidly in brickwork
the remaining portion thereof being exposed in the heating space F. and it is so
arranged that a portion, which is closed, of its upper surface is within the before
mentioned chamber, whilst the remainder, that is to say, about one half or two
thirds thereof, is situated within an enclosed space K. this arrangement will render
easy access to the contents of the said pot without the necessity of disturbing the
contents of the chamber G¹. M. is a ventilating door or trap in the wall separating
the chamber G¹ from the space K., it can be opened or shut as required, and serves
to keep the space K. cool, and allows of the operators remaining in a current of
cool pure air.
When the apparatus herein before described is to be employed for remelting the
unconverted lead refuse from the converting chamber the lead is fed to the pot A.
Figure 2. through an opening a' at that side of the chamber opposite the
opening H. The said opening a¹ is closed by two doors a and c; the door u. opens
inwards and is hinged at the top, it is of such a size that the lower side falling on
the bed plate b., which is on a level with the top of the pot A, it will retain a
position inclining inwards, the door c. closes the opening on the outside.
lead to be recast is placed on the bed plate b. and is pushed forward until it falls
into the pot A. when the door a falls and closes the outlet, thus guarding the
attendant from the fumes. When the door a. is open the rush of air inwards will
prevent the escape of gases or vapours.
The
Acetic acid mixed with oxides of nitrogen and water or watery vapour when
introduced into the converting chamber, have the power of combining with lead
and assisting in the formation of white lead, the higher oxides of nitrogen act more
energetically than the lower oxides and are, moreover, less expensive and more
economical I, therefore, prefer to use them. In a prior specification I have
described and claimed the use of nitric acid mixed with acetic acid and water or
watery vapour in this specification I desire to describe as the second part of my
present invention the use of other suitable oxides of nitrogen mixed with acetic
acid and water or watery vapour, and more particularly Binoxide of nitrogen or
nitric oxide and the nitric per oxide and nitrous acid. I have not been able to
ascertain whether all oxides of nitrogen will effect the desired object but I desire
to limit my claim to such of the higher oxides of nitrogen as will cause the
necessary corrosion of metallic lead. A supply of air and carbonic acid is admitted
to the converting chamber, with the gases and vapours of the acetic acid, oxide of
nitrogen and water or watery vapour, as will be well understood.
The third part of this invention relates to an improved method of supplying the
requisite gases and vapours to the interior of the converting chamber used in the
manufacture of white lead by means of a steam injector and in the construction
and arrangement of apparatus to be employed therefor, whereby a regular supply
can be maintained or the same may be regulated at will.
The nozzle of the steam pipe is arranged within a tube so connected with a
source of supply of air and carbonic acid that the steam will draw with it a
quantity of air and carbonic acid from any suitable source, and the steam, air and
carbonic acid being brought into contact with the necessary acid liquid will carry
with it a quantity of the same, in the form of vapour, through a suitable channel
into the converting chamber.
Figure 3. is a longitudinal section of an apparatus which I employ for the
purpose lastly referred to and it is constructed and arranged in the following
manner. A' is a vessel in which the supply of carbonic acid is generated by any
suitable means, but, in some cases instead of employing the vessel A¹ I obtain
the carbonic acid either directly or indirectly from any suitable furnace, the
carbonic acid, together with air, passes through a pipe into a vessel B₁ containing
water or any suitable liquid by which the carbonic acid is moistened and purified,

page_text: the upper part of the vessel B¹ is connected by a pipe with the tube F¹ surrounding
the nozzle of the injector. H' is an aspirator for containing a supply of the
requisite acids, and I a funnel for conducting the latter into the continuation F¹¹
of the tube F¹. As the acid liquid falls into the pipe F¹ it is met by the steam,
from the injector, and is carried, in the form of vapour, with the same and the
carbonic acid and air into the converting chamber. The supply of steam, the
amount of acid vapours and also the supply of air and carbonic acid (the latter by
means of the valves a² a²) admitted into the converting chamber can be regulated,
as will be well understood.
Figure 4. is a modification of the apparatus lastly described, in which the .
carbonic acid and air are admitted into the pipe F¹, these gases are then conducted
into the purifying chamber B¹ through the pipe F¹ and are conducted thence
through the pipe I into the chamber B containing the acid liquid, from this
chamber they pass with a quantity of acid vapour through the pipe J. into the
converting chamber.
It will be understood that the pipes, chambers and other parts of the apparatus,
into contact with which the acid liquid or vapours come, must be made of suitable
material to resist the action thereof.
This invention relates fourthly, to the arrangement of troughs and materials
contained therein within the chamber for the purpose of preserving the gases and
vapours in a saturated condition. The troughs, which are constructed of wood or
other suitable material, are arranged within the chamber at various levels above
the floor, and within the said troughs is placed water or diluted acid together with
lumps of graphite, coke or other electro-negative to lead. The said lumps of
graphite or other material are connected with the lead to be converted by strips
of platinum, tin or other suitable conductive material. The currents of vapours
and gases which are admitted to the chamber in a saturated condition, on coming
into contact with the lead, are, to a great extent, deprived of the acids and other
active agents and are thereby rendered dry and unfit for further rapid action, but,
in that state, they possess great power of absorption and coming into contact
with the fluid in the troughs they absorb vapour therefrom and again become
saturated.
The contents of the troughs being electrically connected with the lead, as
hereinbefore described, a galvanic combination is formed, in which the lead is
the positive metal, and, in this condition, is readily attacked by the gases and
vapours.
In order to effect a perfect and equal diffusion of the gases within the chamber
I prefer to lay the perforated ends of the pipes, employed for conducting the same,
a short distance above the floor and along the length of the chamber within an
enclosure of wood, and on the said enclosure I place a covering of cocoa nut
matting or other similar material which will resist the action of the acid gases
and vapours.
This invention relates lastly, to an improved apparatus, for drying the converted
lead, which is shown at Figure 5 of the accompanying drawings.
A vessel x. x. x. x. is arranged within a larger vessel y. y. y. y. in such a manner
that the upper sides of the two vessels are on the same level, and a space is left
between the outer surface of the sides and bottom of the inner vessel and the inner
surface of the sides and bottom of the outer vessel. An exhaust pipe E¹ leads
from one side of the inner vessel to the jacket pipe F2 of the steam injector. An
air pipe H is arranged in the space between the bottoms of the vessels and
between the sides thereof, as shown, and opens into the upper part of the inner
vessel. On the injector being set in action the steam, which may be superheated,
passes into the space between the two vessels and travelling in the direction shown
by the arrows eventually escapes through the flue I drawing with it through the
exhaust pipe E¹ the vapours contained in the inner vessel. The heat of the said
steam serves to dry the white lead which is contained within the inner vessel, and,
at the same time, to raise the temperature of the air supply passing through the

page_text: pipe H. The said air supply, which may be heated before passing through the
pipe H2, is drawn into the inner vessel by the action of the exhaust hereinbefore
described. Instead of placing the white lead on one floor within the inner vessel,
it is, in some cases, placed on a series of shelves or floors arranged at a short
distance above each other in such a manner that the air entering the vessel
through the pipe H2 will travel over the top shelf or floor and thence into the
space between the latter and the second shelf or floor and so on until having
passed over the white lead on the lowest shelf or floor it is finally drawn into the
exhaust pipe E¹, as hereinbefore described, which, in this case, is connected with
the bottom of the vessel x. x. x. x.
Mh 100%
VAUGHAN & SON,
Agents for the Applicant.

page_text: Improvements in the Manufacture of White Lead and in
Apparatus to be Employed therefor.
I, EDWARD VINCENT GARDNER, of Berners College, Berners Street, .in the
Parish of Marylebone, in the county of Middlesex, Professor of Chemistry, 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 said invention relates to improvements first, in apparatus for melting the
lead to be converted into white lead; secondly, in the gases and vapours admitted
to the converting chamber; thirdly, in the method of supplying the vapours and
gases, necessary for the process of conversion, to the converting chamber; fourthly,
in the arrangement of troughs and materials within the converting chamber in
order to preserve the contents thereof in a proper saturated condition; and lastly,
in an improved apparatus for drying the white lead after the process of con-
version.
In the following description of this invention reference is made to the accom-
panying drawings.
,
The apparatus, for melting the lead to be converted into white lead, constituting
the first part of this invention is constructed and arranged as follows:-
Figure 1. is a sectional view of the apparatus. The furnace E. is enclosed in
order to prevent the escape of any noxious gases or vapours. A. and B. are two
cast iron pots which are united at their lower parts by the channel pipe C. and at
their upper parts by the connecting piece or cover D. These pots are set in brick-
work in such a manner that the products of combustion passing into the space F.
can play round the pot A. and against one side of the pot B. The walls G. G.
enclose a chamber G₁ within which is the pot A., a chimney I. leads from the upper
part of this chamber, any portion of the top of the pot B., which is within the
chamber G¹, is closed. The heated products of combustion after heating the pots
flow upwards through openings in the cover of the heating space F., which cover is
on a level with the top of the pots, into the before mentioned chamber, and are
thereby brought into contact with the surfaces of the melting metal in the pot A.
and tend to prevent the oxidation of the same, a disadvantageous result which
would occur if air alone were allowed to come into contact with the metal. The
lead to be melted is placed into the pot A. through a door H. at one side of the
chamber G, and, when melted, it runs, free from dross and scoriæ, through
the channel pipe C., into the pot B.
The dross and scoriæ is removed, as desired,
from the pot A. through the door H. The pot B. is partially set solidly in brick-
work the remaining portion thereof being exposed in the heating space F. and it is
so arranged that a portion, which is closed, of its upper surface is within the before
mentioned chamber, whilst the remainder, that is to say, about one half or two
thirds thereof, is situated within an enclosed space K., this arrangement will
render easy access to the contents of the said pot without the necessity of dis-
turbing the contents of the chamber G¹. M. is a ventilating door or trap in the
wall separating the chamber G¹ from the space K, it can be opened or
shut as

page_text: required, and serves to keep the space K. cool, and allows of the operators
remaining in a current of cool pure air.
When the apparatus hereinbefore described is to be employed for remelting the
unconverted lead refuse from the converting chamber the lead is fed to the pot A.
Figure 2. through an opening a' at that side of the chamber opposite the opening H.
The said opening a¹ is closed by two doors a. and c.; the door a. opens inwards
and is hinged at the top, it is of such a size that the lower side falling on the
bed plate b., which is on a level with the top of the pot A. it will retain a position
inclining inwards, the door c. closes the opening on the outside. The lead to be
recast is placed on the bed plate b. and is pushed forward until it falls into the
pot A. when the door a. falls and closes the outlet, thus guarding the attendant
from the fumes. When the door a. is open the rush of air inwards will prevent
the escape of gases or vapours.
Acetic acid mixed with oxides of nitrogen and water or watery vapour when
introduced into the converting chamber, have the power of combining with lead
and assisting in the formation of white lead, the higher oxides of nitrogen act
more energetically than the lower oxides and are, moreover, less expensive and
more economical, I, therefore, prefer to use them. In a prior specification I have
described and claimed the use of nitric, acid mixed with acetic acid and water or
watery vapour, in this specification I desire to describe as the second part of my
present invention the use of other suitable oxides of nitrogen mixed with acetic
acid and water or watery vapour, and more particularly Binoxide of nitrogen or
nitric oxide and the nitric per oxide and nitrous acid. I have not been able to
ascertain whether all oxides of nitrogen will effect the desired object, but I desire
to limit my claim to such of the higher oxides of nitrogen as will cause the
necessary corrosion of metallic lead. A supply of air and carbonic acid is admitted
to the converting chamber, with the gases and vapours of the acetic acid, oxide of
nitrogen and water or watery vapour, as will be well understood.
The third part of this invention relates to an improved method of supplying the
requisite gases and vapours to the interior of the converting chamber used in the
manufacture of white lead by means of a combined steam injector-evaporator,
whereby a regular supply can be maintained or the same may be regulated
at will.
The nozzle of the steam pipe is arranged within a tube having several openings
one of these so connected with a source of supply of air and carbonic acid that the
steam will draw with it a quantity of air and carbonic acid, from any suitable
source, and the steam air and carbonic acid as a combined jet or current are made
to strike against a supply of acid or acids entering at a second opening of the tube in
front of the jet of steam air and carbonic acid by which the necessary acid or acids
arc evaporated and carried in the form of vapour through the proper channels to
the converting chamber.
Figure 3. is a longitudinal section of an apparatus which I employ for the
purpose lastly referred to and it is constructed and arranged in the following
manner. A¹ is a vessel in which the supply of carbonic acid is generated by any
suitable means, but, in some cases, instead of employing the vessel A¹ I obtain the
carbonic acid either directly or indirectly, from any suitable furnace, the carbonic
acid together with air, passes through a pipe into a vessel B¹ containing water or
any suitable liquid by which the carbonic acid, is moistened and purified, the upper
part of the vessel B¹ is connected by a pipe with the tube F1 surrounding the
nozzle of the injector. H¹ is an aspirator for containing a supply of the requisite
acids, and I a funnel for conducting the latter into the continuation F" of the
tube F. As the acid liquid falls into the pipe F it is met by the steam, from the
injector, and is carried, in the form of vapour, with the same and the carbonic acid
and air, into the converting chamber. The supply of steam, the amount of acid
vapours and also the supply of air, and carbonic acid (the latter by means of the
valves a a) admitted into the converting chamber, can be regulated, as will be
well understood.--

page_text: It will be understood that the pipes, chambers and other parts of the apparatus,
into contact with which the acid liquid or vapours come, must be made of suitable
material to resist the action thereof.
This invention relates fourthly, to the arrangement of troughs and materials
contained therein within the chamber for the purpose of preserving the gases and
vapours in a saturated condition. The troughs which are constructed of wood or
other suitable material are arranged within the chamber at various levels above
the floor, and within the said troughs is placed water or diluted acid together with
lumps of graphite, coke or other electro-negative to lead. The said lumps of
graphite or other material are connected with the lead to be converted by strips of
platinum, tin or other suitable conductive material. The currents of vapours and
gases, which are admitted to the chamber in a saturated condition, on coming into
contact with the lead, are, to a great extent, deprived of the acids and other active
agents and are thereby rendered dry and unfit for further rapid action, but, in that
state, they possess great power of absorption and coming into contact with the fluid
in the troughs they absorb vapour therefrom and again become saturated.
The contents of the troughs being electrically connected with the lead, as herein-
before described, a galvanic combination is formed, in which the lead is the positivo
metal, and, in this condition, is readily attacked by the gases and vapours.
In order to effect a perfect and equal diffusion of the gases within the chainber
I prefer to lay the perforated pipes, employed for distributing the gases and vapours
in the chamber, a short distance above the floor and along the length of the chamber
within an enclosure of wood and on the said enclosure I place. a covering of cocoa-
nut matting, wooden wattle hurdles or other suitable material which will resist the
action of the said gases and vapours.
This invention relates lastly to an improved apparatus, for drying the white lead
which is shown at Figure 4. of the accompanying drawings.
A vessel x. x. x. x. is arranged within a larger vessel y. y. . y. in such a manner
that the upper sides of the two vessels are on the same level and a space is left
between the outer surface of the sides and bottom of the inner vessel and the
inner surface of the sides and bottom of the outer vessel. An exhaust pipe E¹
leads from one side of the inner vessel to the jacket pipe F2 of the steam injector.
An air pipe H2 is arranged in the space between the bottoms of the vessels and
between the sides thereof, as shown, and opens into the upper part of the inner
vessel. On the injector being set in action the steam, which may be superheated,
passes into the space between the two vessels and travelling in the direction shown
by the arrows eventually escapes through the flue I drawing with it, through the
exhaust pipe E', the vapours contained in the inner vessel. The heat of the said
steam serves to dry the white lead, which is contained within the inner vessel,
and, at the same time, to raise the temperature of the air supply passing through
the pipe H. The said air supply which may be heated before passing through the
pipe H is drawn into the inner vessel by the action of the exhaust herein before
described. Instead of placing the white lead on one floor within the inner vessel,
it is, in some cases, placed on a series of shelves or floors arranged at a short
distance above each other in such a manner that the air entering the vessel through
the pipe H will travel over the top shelf or floor and thence into the space between
the latter and the second shelf or floor and so on until having passed over the white
lead on the lowest shelf or floor it is finally drawn into the exhaust pipe E' which,
in this case, is connected with the bottom of the vessel x. x. x. x.
Having now particularly described and ascertained the nature of my said inven-
tion and in what mauner the same is to be performed I declare that what
I claim is
In the manufacture of white lead.
First The superature consisting

page_text: space K., substantially as, and for the purposes, hereinbefore described, and shown
in Figures 1. and 2. of the accompanying drawings.
Secondly. The use of the higher oxides of nitrogen, other than nitric acid, mixed
with acetic acid and water or watery vapour for the purpose of manufacturing
white lead, substantially as herein before described.
Thirdly. The method of supplying the gases and vapours to the converting
chamber by means of a combined injector-exhaust-evaporator, substantially as
herein before described.
Fourthly. The arrangement of the troughs containing water or diluted acid and
an electro-negative to lead, and the connection thereof with the lead to be
converted, within the converting chamber, substantially as herein before described.
And Fifthly. The construction of apparatus for drying white lead, substantially
as hereinbefore described and shown at Figure 4. of the accompanying drawings.
Dated this 24th day of December 1885.
VAUGHAN & SON,
Agents for the Applicant.