Improvements in the Manufacture of Ultramarine, and in Furnaces or Ovens and Apparatus to be Used in this Manufacture.
Year: 1886

page_text: Improvements in the Manufacture of Ultramarine, and in
Furnaces or Ovens and Apparatus to be Used in this
Manufacture.
I LÉON JEAN BAPTISTE AIMÉ JOSEPH BOUILLET of N° 4 Vine Street in the
City of London Color Manufacturer 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 has for its object improvements in the manufacture of ultra-
marine and in furnaces or ovens and apparatus to be used in this manufacture.
I prepare the materials as usual in a thoroughly mixed and finely pulverized
condition; I then proceed as follows:-
I provide moulds which may be of wood or other material, say about 6 inches
square on the base and nine inches high, but the dimensions may be varied. In
these moulds I place paper bags or envelopes made of a size to fit, the moulds.
I fill the bags with the powdered materials giving meanwhile a continuous move-
ment to the moulds by means of a mechanical shaker or jigger to shake the powder
down as closely as it will lie. When the paper packet or envelope is well filled
I cover the surface of the material with a thin sheet of wood or cardboard cut to
fit the envelope. I then close the packet by folding over the paper and secure it
with paste. I then remove the packet from the moulds for which purpose the
bottom of the mould may be moveable and may be caused to rise so as to eject the
packet after it has been closed; or the delivery of the packet may be effected in,
any other convenient manner.
The paper of which the envelopes are made should be stout and should contain
much calcareous or mineral matter so that it may effectually separate the packets
when in the oven and prevent adhesion taking place in roasting or burning. Or
the paper may be dipped in a solution which will render it incombustible and then
dried.
Having prepared a series of brick like packets in the manner described I place
them within retorts or muffle like chambers in a furnace or oven such as I will
presently more fully describe.
I place the packets on end in the muffle by means of an instrument which I con-
struct specially for this purpose; it consists of a board with a handle attached and

page_text: of a size to receive upon it a row of packets extending across the muffle. It is also
provided with a pusher to displace the packets from the board and deposit them in
place within the muffle. So I arrange in order row after row of packets until the
muffle is full when the end of the chamber is bricked up and the firing is proceeded
with. The packets should be so placed in the muffle that the sheet of wood or
cardboard inserted into the envelope before closing it rests upon the floor of
the muffle, then the blocks are prevented from adhering to the surface on which
they rest.
In consequence of the materials being arranged in packets as I have described
the gases which they give off when heated are able freely to escape; the materials
become uniformly cooked throughout, and a better product is obtained than at
present; besides which there is great saving of labour in charging the oven or
furnace and also in removing the goods. When the firing is completed the
materials will be found to have retained the brick like form and these bricks are
easily removed from the muffle.
The furnace or oven is rectangular and consists of a principal chamber with
four side walls, a ceiling or roof and a floor. The ceiling is formed of fire tiles
supported upon iron bars in such a manner that they can be easily removed, to give
access to the interior of the furnace chamber to facilitate repairs. The floor is of
brick work or masonry and across the floor from side to side there are a series of
channels serving as flues. At one end of each channel at the side of the furnace
chamber there is a fire place with bars, on which fuel is burnt. Or in place of
employing a series of fire places there may be a single long fire place passing from
end to end of the furnace chamber and from which the flues already mentioned pass
out laterally. Solid fuel may be employed or gas or hydro-carbon liquid; the fire
place of course being adapted to the nature of the fuel which it is intended to burn.
Over these flues I construct three or other number of muffles; they extend from
end to end of the furnace chamber. The fire tiles forming the floor or bottom of
each muffle are laid over the flues already described and cover them in at the top.
The sides of the muffles are composed of hollow blocks of fire clay or refractory
ware and the roof of the muffle consists of a flat arch of thin fire bricks abutting
upon the blocks which form the side of the muffle and covered with refractory
cement to prevent the escape of gas. The heated products from the fire or fires
passing along the flues impinge upon the under side of the floors of the muffles and
also enter the hollow blocks which form the sides of the muffle chambers.
Refractory bricks are provided to deflect the flame and gas up into the interior of
the hollow blocks. On reaching the extremities of the lower flues the heat ascends
by numerous passages through the blocks which form the outer side of the muffle
furthest from the fire. In this way the flames and gases from the fire reach the
top of the muffles and they then return over the arched roofs of the muffles to the
side of the furnace where the fire place or places are situate; a flue then leads
them away to a chimney stack.
Regulators or dampers are provided in the passages connecting the flues on the
under sides of the muffles with the space above their roofs and there are also
dampers in the numerous flue passages by which, after returning over the tops
of the muffles the products of combustion pass away. By means of these dampers
the heat in every part of the furnace can be regulated so that it may be made
perfectly uniform throughout.
The materials during the process disengage a large quantity of sulphurous
vapours.
In order to convey away these gases I provide a pipe of fire resisting pottery
ware, it passes across the bottoms of the muffles from side to side and is perforated
for the gas to enter the pipes. The pipe passes out from the furnace at one side
and is connected with a flue in which a draught is maintained sufficient to carry
away the gas and vapours which, are of a noxious character and unfit to be
admitted into the atmosphere. Besides the gas and vapour contain a considerable
quantity of sulphur which may be profitably retained. The gases may be purified

page_text: Figure 1 is a sectional plan showing the furnace chamber and parts of the muffles
which it contains.
Figure 2 is a transverse vertical section.
Figure 3 is a side elevation partly in section.
Figure 4 is a plan of a portion of the roof or ceiling of the furnace.
Figure 5 is an end elevation.
Figure 6 is part of a vertical section showing the arrangement when a single fire
place is employed.
.
Figure 7 is a transverse section through one of the muffles and shows the goods
in the form of brick like packets arranged within it.
Figure 8 is a side elevation of the apparatus which I employ in placing the
packets in the muffles.
A. A. are the fire places. B. B. are the series of flues, into which the heated
products from the fires pass. C. C. are the fire tiles forming the bottom of the
muffles and which enclose the flues B at the top. D. D. D. are hollow fire brick or
refractory blocks forming the sides of the muffles; they are so formed that the heat
from the flues may circulate within them, so that the sides of the muffles as well as
the bottoms and tops may be effectually heated. Z. Z. are refractory bricks
deflecting the flames and gases upwards into the interior of these blocks. E. E. are
the blocks which form the outer side of the further muffle; they are different in
form from the blocks D and by them the flames and gases from the fire can pass up
into the space above the muffles. E¹ E' are dampers by which the passages in the
blocks E. can at pleasure be closed. F. F. F. are the arches of fire tile forming the
roofs of the muffle, they abut upon the blocks D and E as the drawing shows.
G. G. are the flue passages by which the products of combustion pass out from the
furnace chamber into a flue H leading to a chimney. G₁ G¹ are dampers in the
flue passages G.-I. I. are fire tiles which close the furnace chamber at the top they
are supported by iron bars K.-The bars K are T form in section and are supported
upon the side walls of the furnace and also upon brick piers L. L. built on the tops
of the hollow fire brick blocks D. D.-M is a layer of sand which is laid over the
top of the ceiling blocks I.-N is a pipe of fire resisting pottery passing through
the muffles and the part of the pipe within the muffles is perforated so that the
gas generated in the muffles may enter it.-O, is the flue into which the pipe N
leads. The muffles are open at both ends for the material enclosed in packets or
envelopes as described to be arranged in the way clearly shown in Figure 7 where
P. P. represent a row of six packets standing on end upon the muffle bottom.
The packets are placed six at a time and row by row until the muffle is full.
When the muffles are charged they are bricked up at the ends, sight holes only
being left as indicated in Figure 5. All of the muffles being thus filled and closed
the fires are lighted and gradually the muffles are brought to the requisite high
temperature which is such as is at present usual to employ in this manufacture but
the arrangements of my furnace admit of greater regularity in the heating than
has heretofore been possible.
After firing the muffles are allowed to cool and during the cooling I prefer to
admit oxygen gas at the apertures S. S. The material absorbs the gas and then,
assumes the brilliant blue hue which is usually desired in the finished product.
In place of supplying oxygen air may be admitted by the openings S. but
I prefer to use oxygen as a finer color is so obtained. The muffles are allowed to
get nearly cold before they are opened, the goods are then removed and the
product of ultramarine blue is prepared for the market in the usual manner.

page_text: In Figure 8, Q is the board or surface on which a row of six or other number of
packets is arranged for insertion into the muffle. R is the handle. S is the
pusher by which the packets are displaced from the board. S¹, is the handle of the
apparatus.
The way of employing this apparatus will be readily understood; when loaded
it is inserted into the muffle and when the packets are in place the handle S¹ is
pressed forward and the handle R drawn back. Stops at S limit the movement."
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 manufacture of ultramarine blue forming the color producing materials
into packets or masses of uniform dimensions and arranging these in muffles
within a muffle furnace and there performing the roasting operation substantially
as described.
2. When so conducting the manufacture of ultramarine blue the use to contain
the colour producing materials during roasting of envelopes of paper highly charged
with mineral matter substantially as described.
3. In the manufacture of ultramarine roasting the colour producing materials in
muffles or retorts provided with a pipe for leading off the gases generated to a flue
or receiver substantially as described.
4. In the manufacture of ultramarine the use of a furnace or oven with muffles
having a floor of fire tiles laid over flues passing transversely beneath the muffles;
hollow sides within which the heat can circulate and an arched roof abutting upon
the hollow sides substantially as described.
5. In the manufacture of ultramarine the use of a furnace containing muffles,
and closed at the top by a ceiling of fire tiles supported upon iron bars easily
removeable to give access to the muffles substantially as described.
6. The furnace or oven for use in the manufacture of ultramarine substantially
as described and illustrated by the annexed drawings.
7. In the manufacture of ultramarine introducing oxygen into the muffles in
which the colour producing materials are roasted substantially as described.
8. In the manufacture of ultramarine the use of the apparatus represented by
Figure 8 to deposit the packets or blocks of colour producing material within the
muffle.