Improvements in Apparatus for the Manufacture of Metallic Pigments or Compounds, and in the Production of Lead and Zinc Pigments or Compounds and Combinations of these by Means of such Apparatus.
Year: 1893

page_text: Date of Application, 6th Apr., 1893
Complete Specification Left, 5th Feb., 1894-Accepted, 10th Mar., 1894
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for the Manufacture of Metallic
Pigments or Compounds, and in the Production of Lead and
Zinc Pigments or Compounds and Combinations of these by
Means of such Apparatus.
I, ANDREW CHARLES JOSEPH CHARLIER, of No. 136 Holm Street, Glasgow, in
the County of Lanark, Analytical Chemist, do hereby declare the nature of this
invention to be as follows :-
My invention relates, more particularly to the process and apparatus for the
manufacture of lead pigment described in the Specification to Hannay's Patent
No. 1282 of 1889, whereby lead ore containing sulphur was volatilised in a chamber
in which combustible gas was at the same time produced, the resulting mixture of
gases and lead fumes being then burnt by the admission of air in an oxidising
chamber.
The said volatilizing chamber was in open communication through the oxidising
chamber with the condensers in which the oxidized lead fumes were condensed, Bo
that on first starting the apparatus as well as in adding fresh fuel from time to
time, the impurities resulting from the combustion of fuel in the volatilising chamber
passed into the oxydising chamber and thence into the condensers aud deteriorated
the lead product therein.
According to one of my present improvements I prevent such deterioration by
separating the producer furnace or volatilizing chamber from the oxidising chamber
by means of a damper closing the communication between them, and also providing
such producer furnace, as and when required, with a separate chimney flue, also
provided with a damper; so that when the apparatus is first started, or fresh fuel
is added, the communication between the producer furnace and the oxidizing
chamber is closed by means of the damper, and the damper to the furnace chimney
flue is opened, so that the combustion gases from the furnace will escape through
the latter.
After the furnace has thus been fairly started or renewed and made ready for
use the chimney flue damper is closed, and the damper of the opening leading to
the oxidizing chamber is lifted or opened and the process of manufacture then
proceeds.
According to another improvement, I introduce jets of steam superheated or
otherwise among the fumes as they pass from the producer furnace into the
oxidizing chamber by means of which I prevent discolouration of the resulting
product and the formation of slag in the oxidizing chamber.
Instead of constructing the chamber of the producer furnace of a square or
rectangular section on plan, I construct the same more or less in an elliptical form
as it has been found in practice that the materials do not get properly fed into the
corners of the rectangular section, resulting in a waste of fuel at those points.
Instead of or in. addition to supplying the air to the oxidizing chamber from
branches on the pipes leading the air supply to the producer furnace, I lead
separate branches from the main air trunk to the oxidizing chamber, whereby the
air is made to enter the latter at an increased pressure.
According to another improvement, I employ the above described apparatus for
producing a compound of sulphate of lead and oxide of zinc known as and sold for
several years as "marine white "for which purpose I introduce into the producer
furnace, together with the lead ore, a suitable proportion of zinc ore, zinc ashes,
zinc refuse, spelter, zinc blende, or other material containing zinc, so that the zinc

page_text: .
becomes volatilized together with the lead compounds and the mixed fumes in
entering the oxidizing chamber together with the combustible gases, become
oxidized and are subsequently condensed together in the form of a compound lead
and zinc pigment.
I also employ the above described apparatus for the manufacture of zinc oxide
and carbonate of zinc for pigments or for other purposes.
In carrying out this part of my invention I utilise zinc ashes, zinc refuse, or
residues such as those obtained after distilling the chlorides of ammonium and zinc
from zinc skimmings, also hard and soft spelter, zinc cuttings and virgin spelter,
and zinc blende.
When using hard and soft spelter or virgin spelter or zinc blende I first heat it
in a reverberatory furnace and then plunge it into cold water so as to break it up
into small particles.
When using zinc cuttings, I reduce them into small particles and when using
zinc ashes or zinc refuse &c. I first carefully riddle them to separate the coarse from
the fine and then powder the coarse in a mortar mill and thoroughly separate them
from all dirt by washing with water or otherwise.
These several substances in a finely divided condition I volatilise in the above
described producer furnace by throwing them on the top of the fire after getting
the furnace up to a heat of about 1300° C. The free zinc volatilised and the
fumes along with the produced gases of which carbonic oxide forms part pass into
the combustion chamber to which air is admitted. In this chamber the combustible
gases burn and the fumes become oxidized producing zinc oxide.
From the combustion chamber the gases along with zinc oxide fumes pass up
a vertical tower or flue (in which part of the zinc oxide is deposited) to a condenser
in which by means of a steam jet acting as an injector the gases and fumes are
caused to pass through water. In this water the principle part of the zinc oxide
is deposited but a large percentage of the zinc treated comes over as soluble
compounds which are held in solution in the water. The water containing the
zinc oxide deposited in a wet state and other soluble compounds is drained or
pumped from the condenser tank off the top of the deposited zinc oxide and
subjected to further treatment whilst the deposited zinc oxide is dried and prepared
ready for use. The drained off water containing soluble compounds of zinc is
collected in suitable tanks where an alkaline carbonate is added causing such soluble
compounds to be precipitated as carbonate of zinc. Such carbonate of zinc can
be used as a pigment or by any of the well known processes, such as roasting in a
reverberatory furnace the carbonic acid can be driven off and the finest white oxide
of zinc be formed.
I also use the lead sulphate and the zinc oxide or both in combination produced
as above described from the furnaces in certain cases without passing them through
the condensers.
Dated this 6th day of April 1893.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Apparatus for the Manufacture of Metallic
Pigments or Compounds, and in the Production of Lead and
Zinc Pigments or Compounds and Combinations of these by
Means of such Apparatus.
I, ANDREW CHARLES JOSEPH CHARLIER, of No. 136 Holm Street, Glasgow, in
the County of Lanark, Analytical Chemist, 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 more particularly to the process and apparatus for the

page_text: manufacture of sulphate of lead pigment described in the Specification to Hannay's
Patent No. 1282 of 1889 whereby lead ore containing sulphur was volatilised in a
chamber in which combustible gas was at the same time produced, the resulting
mixture of gases and lead fumes being then burnt by the admission of air in an
oxidising chamber.
The said volatilising chamber was in open communication through the oxidising
chamber with the condensers in which the oxidised lead fumes were condensed so
that on first starting the apparatus as well as in adding fresh fuel from time to
time, the impurities resulting from the combustion of fuel in the volatilising
chamber passed into the oxidising chamber and thence into the condensers and
deteriorated the lead product therein.
According to one of my present improvements I prevent such deterioration by
separating the producer furnace or volatilising chamber from the oxidising chamber
by means of a damper closing the communication between them and also providing
such producer furnace, as and when required, with a separate chimney flue also
provided with a damper; so that when the apparatus is first started, or fresh fuel
is added, the communication between the producer furnace and the oxidising
chamber is closed by means of the damper, and the damper to the furnace chimney
flue is opened when the combustion gases from the furnace will escape through the
latter.
After the furnace has been thus fairly started or renewed and made ready for
use the chimney flue damper, when applied, is closed, and the damper of the
opening leading to the oxidising chamber is lifted or opened and the process of
nianufacture can then proceed.
According to another improvement I introduce jets of steam superheated or
otherwise among the fumes as they pass from the producer furnace into the
oxidising chamber by means of which I prevent discoloration of the resulting
product and the formation of slag in the oxidising chamber. Instead of constructing
the chamber of the producer furnace of a square or rectangular section on plan,
construct the same more or less in an elliptical form as it has been found in practice
that the materials do not get properly fed into the corners of the rectangular
section, resulting in a waste of fuel at those points.
Instead of or in addition to supplying the air to the oxidising chamber from
branches on the pipes leading the air supply to the producer furnace, I lead separate
branches from the main air trunk to the oxidising chamber, whereby the air is
made to enter the latter at an increased pressure.
"
According to another improvement I employ the above described apparatus for
producing a compound of sulphate of lead and of oxide of zinc known as and sold
for several years as
66 marine white for which purpose I introduce into the
producer furnace, together with the lead ore a suitable proportion of zine ore, zinc
ashes, zinc refuse, spelter, zinc cuttings and virgin spelter, zinc blende or other
material containing zinc, so that the zinc becomes volatilised together with the
lead compounds and the mixed fumes in entering the oxidising chamber together
with the combustible gases become oxidised and are partly deposited in the chamber
and the remainder as fumes or vapour are subsequently condensed together in the
form of a compound lead and zinc pigment.
I also employ the above described apparatus for the manufacture of zinc oxide
and carbonate of zinc for pigments or for other purposes.
In carrying out this part of my invention I utilise zinc ashes, zinc refuse or
residues such as those obtained after distilling the chlorides of ammonium and zinc
from zinc skimmings, also hard and soft spelter, zinc cuttings and virgin spelter,
and zinc blende.
When using hard and soft spelter or virgin spelter or zinc blende I first, by
preference, beat it in a reverberatory furnace and then plunge it into eold water so
as to break it up into small particles.
When using zinc cuttings I reduce them into small particles and when using zinc
ashes or zinc refuse &c. I first carefully riddle them to separate the coarse from

page_text: the fine and then powder the coarse in mortar mill or otherwise and thoroughly
separate them from all dirt by washing with water or otherwise.
These several substances in a finely divided condition I volatilise in the above
described producer furnace by throwing them on the top of the fire after getting
the furnace up to the required heat, say about 1300° C. The free zinc volatilises
and the fumes along with the produced gases of which carbonic oxide forms part
pass into the combustion chamber to which air is admitted. In this chamber
the combustible gases burn and the fumes become oxidised producing zinc
oxide.
From the combustion chamber, the gases along with zinc oxide fumes pass into
the oxidising chamber where a portion of them fall as zinc oxide and the remainder
pass up a vertical tower or flue (in which also part of the zinc oxide is deposited)
to a condenser in which by means of a steam jet acting as an injector the gases
and fumes are caused to pass through water. In this water the principal part of
the zinc oxide is deposited but a large percentage of the zinc treated.comes over as
soluble compounds which are held in solution in the water. The water containing
the soluble zinc compounds is drained or pumped from the condenser tank off the
top of the deposited zinc oxide and subjected to further treatment whilst the
The drained off water
deposited zinc oxide is dried and prepared ready for use.
containing soluble compounds of zinc is collected in suitable tanks where an
alkaline carbonate is added causing such soluble compounds to be precipitated as
carbonate of zinc. Such carbonate of zinc can be used as a pigment, or by any of
the well known processes, such as roasting in a reverberatory furnace the carbonic
acid can be driven off and the finest white oxide of zinc be formed.
I also use the lead sulphate and the zinc oxide or both in combination produced
as above described from the furnaces in certain cases without passing them through
the condensers.
On the accompanying drawing is shewn the improved construction of furnace
for carrying out the above described processes for the production of lead and zinc
pigments, or of both combined.
Fig. 1 shows a longitudinal section of that part of the apparatus to which the
present improvements relate.
Fig. 2 shews a sectional plan, and Fig. 3 shews a cross section through the
volatilising producer furnace.
Fig. 4 shews a section to a smaller scale of the said apparatus in combination
with the condensing apparatus.
A is the volatilising producer furnace, which is charged with the necessary fuel
through the door a and into which (also through the door a) the mixture of galena,
or other lead ore containing sulphur together with fuel is then introduced. B is
the oxidising chamber and Cis the vertical flue leading to the condensing
apparatus which is of the same construction as before. D is the main air supply
pipe, from which branches D' lead to the tuyeres E' in the volatilising furnace,
while other branches D2 lead to the tuyeres E' in the entrance to the oxidising
chamber.
The volatilising furnace A instead of being made rectangular in plan, is made of
approximately elliptical section as shewn at Fig. 2 for the purpose above stated,
it communicates by a narrow part A' with the oxidising chamber B, and on the
outer side of this passage is provided a damper F by means of which the com-
munication between the volatilising furnace and the oxidising chamber can be
closed. The furnace A is preferably made to communicate by a flue G provided
with a damper G' with a chimney flue G², so that on starting the furnace or on
renewing the supply of fuel the furnace A can be cut off from the oxidising
chamber B by closing the damper F and be made to communicate with the chimney
flue G by opening the damper G¹.
When the apparatus is working the positions of the dampers F and Gare
reversed.
In front of the opening of the passage 'A leading into the chamber B are

page_text: arranged steam nozzles H H supplied with steam from any convenient generator
by a pipe H' or otherwise.
The steam issuing from these nozzles in coming into intimate contact with the
burning mixture of air, combustible gases and lead fumes, passing from the passage A
into the chamber B, becomes decomposed and acts upon the lead compounds so as
to prevent the discoloration of the resulting product, and also so as to prevent the
formation of slag from the combustion taking place in the chamber B. If desired,.
the steam supply may be superheated in which case the pipe H' may conveniently
be formed into a coil in the chamber B, so as to be heated by the combustion.
taking place therein, as indicated by the dotted lines.
A portion of the resulting lead sulphate is precipitated in the chamber B while
the remainder is carried up the flue C and along the horizontal flue I, Fig. 4, at
the end of which is a steam injector J by the action of which the fumes and gases.
are propelled downwards into a condensing chamber K which is partly filled with
water or acidulated water, and in which are immersed a number of perforated or
permeable screens L, so that the gases and fumes forced in between these by the
steam jet are made to pass through the screens and are thereby brought into
intimate contact with the water which takes up the sulphate of lead contained
therein, while the gases issue into the top of the chamber and escape through the
pipe M. The lead sulphate subsides towards the funnel. shaped bottom of the
condensing chamber K from which the mixture of water and sulphate is pumped by
a pump N while water is supplied to the condenser K from a cistern Ó fed by a
ball cock. From the pump N the mixture of water and sulphate is delivered to
washing tanks, where the material is washed in the usual way and whence after
subsidence and decantation the washed sulphate is removed to be dried.
At the bottom of the flue C is a door Ci by which access is given to remove the
powdery sulphate deposited in the flue and in the chamber B.
When the charge in the chamber A is exhausted, the damper F is closed, the-
spent charge is removed through the doors a¹ and a fresh charge having been
introduced through a the operation is repeated as before.
The above described apparatus is equally applicable to the herein described
process for the production of oxide of zinc and other zinc pigments, and of
mixtures of these with lead pigments.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In apparatus for the manufacture of metallic pigments or compounds, such as
is herein referred to, providing a damper for closing the communication between.
the volatilising furnace and the oxidizing chamber for preventing the passage of
impurities resulting from the combustion of freshly charged fuel from the volatilising
furnace A into the oxidising chamber B and thence into the condensing apparatus,.
substantially as described.
2. The use in combination with the volatilizing furnace A and the oxidizing
chamber B, of steam jets for acting upon the lead and other fumes so as to prevent
the discoloration of the product and the formation of slag, substantially as
described.
3. In the manufacture of pigments from lead ores containing sulphur by
volatilizing the lead and effecting its combustion with sulphur and air, the method
of acting upon the burning lead fumes with steam for preventing the discoloration
of the resulting lead product, substantially as described.
4. The production of zinc oxide and other compounds of zinc from zinc ashes,.
ziuc refuse, hard and soft spelter, zinc cuttings, virgin speiter, and zinc blende, or
other materials containing zinc by first reducing these substances to a more or less
finely divided condition and then volatilizing the same in a producer furnace from
which the zinc fumes together with the combustible gases are led into an oxidising
chamber where they enter into combustion with air, the resulting zinc oxide being

page_text: partly deposited in the chamber, while the remainder as fume or vapour is
condensed by means of water in suitable condensing apparatus substantially as
described.
5. In combination with the process for the production of oxide and other
compounds of zinc referred to in the fourth claim, treating with alkaline carbonates
the water containing soluble zinc compounds resulting from the condensation of
the oxide of zinc fumes, whereby the soluble zinc compounds are precipitated as
carbonate of zinc.
6. In the process for the production of oxide and other compounds of zinc
referred to in the fourth claim, adding to the materials containing zinc in the
volatilising furnace, lead ores or other substances containing lead and sulphur in
order by the simultaneous production of the zinc and lead fumes and their
subsequent oxidation and condensation, to produce a compound of zinc oxide and
lead sulphate suitable as a pigment, substantially as described.
Dated this 6th day of February 1804
ABEL & IMRAY,
Agents for the Applicant.