Improvements in or connected with Apparatus for the Manufacture of Sulphuric Acid.
Year: 1890

page_text: Date of Application, 1st Apr., 1890
Complete Specification Left, 1st Oct., 1890-Accepted, 6th Dec.,
1890
PROVISIONAL SPECIFICATION.
Improvements in or connected with Apparatus for the Manufacture
of Sulphuric Acid.
We, EMILE DELPLACE and JULES DELPLACE, Manufacturing Chemists, of Auber-
villiers, near Paris, France, do hereby declare the nature of our invention to be
as follows:-
Our improvements relate chiefly to the pyrite burners and to the leaden chambers
of apparatus for the manufacture of sulphuric acid.
The pyrite-burners are arranged in a row as usual, each burner consisting of five
shallow chambers or floors (instead of six) and communicating at the top with the
collecting chamber extending over the whole row of burners and communicating at
one end with the dust-chamber. This dust-chamber is likewise placed immediately
over the upper compartments of the whole row of burners or kilns and is separated
from the collecting chamber by a vertical partition. The dust-chamber contains a
number of baffle-plates or short partitions, which force the fumes to take a zig-zag
course while passing from one end to the other.
The usual pits at the back of the kiln are omitted, and the roasted pyrites fall
upon small wrought iron trucks, placed underneath the lowest floor and in front of
the kiln.
From the dust-chamber or flue the fumes and gases pass into a cylindrical
concentrating tower, which they enter at the base, and from which they escape at
the top into the upper part of a cylindrical denitrifying tower in which they pass
downward. From the base of the latter the gases pass through a short flue into a
dividing chamber, placed at a right angle to the said flue and having across the
centre a partition, which divides the gases into a right and a left hand current, the
dividing chamber thus having the inlet in the centre and at each end an outlet to
the large leaden chamber.
The leaden chamber, instead of being rectangular, as usual, is curved or polygonal,
and has preferably the shape of a cylindrical or polygonal ring, so that the
gases are constantly obliged to change their direction while passing through the
said chamber.
Instead of a ring, the lead chamber may form part of a ring (with a section cut
out) or a spiral or a helix or other form, suitable to deflect the gases from their
rectilinear and parallel course. There are preferably two inlets near the top of the
chamber, namely one near the centre and one near the circumference, but situated
in the same radius, and as the gases tend to accumulate at the top, a number
of distributing pipes are employed, which lead from the roof radially outward
or inward, and then down over the inner or outer wall to the bottom of the
chamber, so as to allow a distribution of pressure from the top to the bottom of the
chamber.
The constant change of direction of the gases produced by the improved shape of
the leaden chambers, has for its object to produce a difference of speed, and a better
mixture of the gases, those which enter near the centre of the chamber travelling more
slowly than those at the circumference.
The concentrating tower is made of lead, from 6 to 10 millimeters thick, and filled
or lined inside with natural stone incorrodible by acids, such as feldspar, trachyte,
granite, porphyry, volcanic stones.
The denitrifying column is filled with several layers of stone tubes, or with the
materials used in the concentrating tower as mentioned above.
The denitrifying column has for its object, to complete the denitrification of the

page_text: sulphuric acid and to decompose the quantity of nitric acid necessary for the oxidation
of the sulphurous gas.
The dividing chamber mentioned above is filled with horizontal tubes or with
layers of incorrodible natural stones, which favours the minute divisions of the gaseous
products.
The greatest part and frequently the whole of the work of producing sulphuric
acid is completed in this annular chamber, from which the gases may pass to the
Gay-Lussac tower.
In order to utilize the free cylindrical space in the centre, the latter may form a
supplementary leaden chamber, into which the gases are led before entering the
Gay-Lussac condenser for denitrification.
Dated this 21
1000
FAIRFAX & WETTER,
433, Strand, London, Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in or connected with Apparatus for the Manufacture
of Sulphuric Acid.
We, EMILE DELPLACE and JULES DELPLACE, Manufacturing Chemists, of Auber-
villiers, near Paris, France, do hereby declare the nature of our invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:→
J
Our improvements in apparatus for the manufacture of sulphuric acid relate more
particularly to the leaden chambers and to the pyrites burners.
Instead of giving to the leaden chamber or chambers the shape of a more or less
elongated parallelopiped, through which the gases travel in parallel layers, thus requiring
much time to form the desired mixture, we force the gases to take a curved or broken
path by giving to the leaden chamber an annular shape. The inner and outer
circumference of the chamber or of its horizontal cross section may form a circle,
a semicircle, an oval, a polygon, a spiral or any other suitable figure. The floor
of the chamber may be level, or it may form a helical or other suitable inclined'
surface.
In the following description, reference will be made to the accompanying drawing,
in which
Fig. 1, is a horizontal and Fig. 2, a vertical section of a sulphuric acid plant
embodying our invention.
Fig. 3 is a cross section of the improved pyrites burners, along line I-II of
Fig. 1.
The said plant comprises two leaden chambers, the first chamber forming a poly-
gonal ring, with the exception of a sector, which is left open for the reception of
auxiliary apparatus, such as the concentrating column A, the denitrifying column C,
and the dividing chamber E, while the second leaden chamber occupies the centre of
the said ring.
The left half of Fig. 2, is a section through the pyrites burners along line I-I of
Fig. 1, and a section through the open sector of the leaden chamber, looking towards
the front wall h, so as to show the auxiliary apparatus A, C, and E, while the right
half of Fig. 2 is a section through the open sector looking towards the end wall k, so
as to show the Gay-Lussac tower Q.
I
The gases are admitted at the top of the radial front wall or partition, through a
pair of openings and g, one being near the circumference, and the other near the
inner wall of the annular chamber H.
The molecules, which at one moment are nearest to the centre, are shortly after-
wards nearest to the circumference and vice-versa. The mutual contact, friction and
shifting of molecules is continual; the molecules of sulphurous acid meet at every
moment molecules of water and of oxidising matter, thus producing an intimate
combination.

page_text: Let us consider three molecules, namely one of sulphurous,acid, the second of nitrous
acid, and the third of aqueous vapour, which are necessary for the production of
sulphuric acid by the usual method.
As long as they are not simultaneously in contact, the desired chemical com-
bination will not take place. In a rectangular chamber, they may travel side by
side from one end of the, chamber to the other, without ever coming simultaneously
into contact.
T
In our apparatus, this defect is avoided, by the constant changes of the
direction of the gases travelling, through. the chamber,, which produce forced
contacts.
It is found in ordinary practice, that the temperature and pressure of the gases
near the ceiling is higher than at the bottom. In order to equalise the pressure, we
connect the roof or upper part of the chamber with the bottom at suitable intervals
by means of distributing pipes I, which receive a portion of the high-pressure gases
at the top of the chamber and conduct it along the outer or inner circumference down
to the bottom.
Fig. 1, indicates by dotted lines, three distributing pipes I, one of which leads
down along the inner circumference, and two along the outer circumference of the
leaden chamber. In the sectional view, Fig. 4, one of the outer tubes I is shown in
elevation.
From the leaden chamber H, the gases may pass either directly to the Gay-Lussac
or absorption tower, or, as shown by the drawing, they may be led through a radial
pipe K into a supplementary leaden chamber P, which occupies the inside of the
annular chamber H and serves to combine the last remnants of gases, before they are
introduced into the absorption tower through the pipe J..
The drawing shows the wooden framework or skeleton of the leaden chainber
(which is lined with sheet lead, as usual) and also, the masonry or pillars H¹ which
support the same, but the special construction of the walls and roof is not essential
to the invention.
The pyrites burners or kilns are placed in a row, as usual, each burner consisting
of 5 superposed compartments or floors R (instead of six) which communicate with
each other at alternate ends and are provided with doors r. Immediately over the
pyrites burners and, extending the whole length of the row, is situated on one side
the collecting channel T and on the other side the dust-flue or chamber M, which is
separated from the collector by a vertical partition o and communicates with the latter
at one end, as shown.
The dust-flue M is provided with short partitions or deflecting plates N, which
force the fumes to take a zig-zag course. The said fumes pass through openings t
in the roof of the uppermost compartments of the burners into the channel T,
and thence through the dust-flue M into the concentrating, tower, as indicated by
arrows.
Instead of using pits, at the back of the furnace or row of burners, for receiving
the roasted pyrites, the latter are allowed to fall through openings into iron
trucks placed in front of the furnace, below the level of the lowest compartment or
floor.
This construction of pyrites burners has for its principal object, to roast the pyrites
inore completely, so as to utilize nearly all their sulphur.
Our improved sulphuric acid plant also comprises the following auxiliary
apparatus.
A concentrating tower A, which receives the sulphurous fumes directly from the
pyrites burners and utilizes their heat for concentrating the weak chamber-acid to
about 60° Baumé. This tower consists chiefly of a cylinder of sheet lead, preferably
from 6 to 10 millimeters thick, and filled with natural acid-proof stones, such as feld-
spar, trachyte, granite, porphyry, basalt, lava, instead of the siliceous bricks hitherto
employed for this purpose.
The gases, after having been cooled down in the tower A, pass through the

page_text: J
canal B into the denitrifying column C, which contains several layers of stone-
ware tubes, or acid-proof stones, like the tower A, in order to multiply the points of
contact.
This column has for its object, to complete the denitrification of the sulphuric
acid, and to decompose the quantity of nitric acid necessary for the oxidation
of the sulphurous acid. The gases enter the column C at the top and escape at the
bottoni.
By these means, we prevent 'the decomposition of the nitrous products which takes
place in ordinary installations with a single "Glover's tower, owing to an excess of
sulphurous acid gas and a high temperature.
From the denitrifying column C, the gases pass into a collector D. which
contains a central partition dividing them into two equal portions, subsequently
the gases enter a dividing chamber E in the middle of its length, which chamber
contains parallel tubes or acid-proof stone adapted to subdivide the gaseous
products. The gases thus reach the two opposite ends of the dividing chamber
and enter the two pipes F and G, which conduct them to the large leaden chamber 'H
described above. Qis a Gay-Lussac tower, into which the gases pass from the leaden
chambers.
Having now particularly described the nature of our invention and in what manner
the same is to be performed, we declare, that we claim :-
i...
1. In apparatus for the manufacture of sulphuric acid, an annular leaden chamber,
substantially as described and for the purposes specified.
2. In apparatus for the manufacture of sulphuric acid, an annular leaden chamber
provided with two inlets at unequal distances from the centre or axis of the chamber,
substantially as described and for the purposes specified.
3. In apparatus for the manufacture of sulphuric acid, a leaden chamber having
the shape of a circular ring with a sector cut out, the said chamber being
provided at one end with two gas inlets at unequal distances from the centre
and at the other end with a gas outlet, substantially as described and for the purposes
specified.
4. In apparatus for the manufacture of sulphuric acid, a leaden chamber adapted to
form a circuitous path for the gasos travelling from one end to the other and
provided with distributing pipes leading from the upper part to the lower part of the
chamber along the inner or outer wall, substantially as described and for the purposes
specified.
5. In apparatus for the manufacture of sulphuric acid, the combination of a row of
pyrites-burners, with a collecting chamber situated immediately over the said
burners and communicating with each of them, and a dust-flue placed parallel
with the collecting chamber over the whole row of burners and separated from the
said chamber by a vertical partition, the said dust-flue communicating at one end
with the collecting chamber and having short partitions, adapted to deflect the fumes
into a zig-zag course while passing to the other end of the flue, substantially as
described.
さ
6. In apparatus for the manufacture of sulphuric acid, a pyrites-burner constructed
and adapted to operate substantially as described and shown.
7. In apparatus for the manufacture of sulphuric acid, the combination of a leaden
chamber having two gas inlets at unequal distances from the centre, with a dividing
chamber interposed between the denitrifying tower and the leaden chamber, the said
dividing chamber having in the centre a gas inlet and at each end an outlet towards
the leaden chamber, and being filled with parallel rows of tubes or with natural acid-
proof stones adapted to subdivide the two currents of gases on their passage from the
centre to the ends of the dividing chamber, substantially as described and for the
purposes specified.
8. In apparatus for the manufacture of sulphuric acid, the combination of
annular leaden chamber H; with concentrating tower A, denitrifying. column C,

page_text: collector D, and directing chamber F, substantially as described and for the purposes
specified.
Dated this 25th day of September 1890.
EMILE
DELPLACE.
JULES DELPLACE.
By Fairfax & Wetter,
433, Strand, London, Agents.