Method for the Manufacture of Sulphur Trioxide (Sulphuric Anhydride).
Year: 1898

page_text: Date of Application, 11th Mar., 1898
Complete Specification Left, 4th July, 1898-Accepted, 27th Aug., 1898
PROVISIONAL SPECIFICATION.
Method for the Manufacture of Sulphur Trioxide (Sulphuric
Anhydride).
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, Chancery
Lane, in the County of London, Chartered Patent Agent, do hereby declare the
nature of this invention (as communicated to me from abroad by The Farbwerke
vormals Meister Lucius & Brüning of Hoechst a/ Main in the Empire of Germany,
Chemical Manufacturers), to be as follows:-
The manufacture of sulphur trioxide (sulphuric anhydride) consists, as is known,
in treating sulphurous anhydride (sulphur dioxide) together with the requisite oxygen
and conducting the hot mixture over or through a contact body. The supply
of heat required for the reaction. necessitated hitherto the use of complicated
machinery as well as a great amount of fuel.
My correspondents have discovered that this machinery may in great part be
dispensed with, thus enabling a great economy of fuel to be effected, if the counter
current principle or other means be used, so that the heat of combination set
free by the reaction of SO₂ +0 SO, be employed for heating the entering
gas-current.
.
==
The following example illustrates one arrangement for utilising the heat of
combination according to this method.
In a counter current apparatus, Figs. 1 and 2 of the accompanying drawing, are
first heated to the temperature necessary for the reaction the entering gases
containing SO, & 0 by a direct supply of heat. As the mixture passes through
the contact substance, oxidation to SO, takes place and consequently the heat of
combination is set free.
Thus gases containing SO, and passing away at A from the contact body, have
a much higher temperature than the gases containing SO, entering at E.
The gases containing SO, are then caused to meet those containing SO, and the
considerable fall in the temperature which occurs ensures a transference of heat
from the gases passing away to those entering the contact body.
The equipoise of the process is easily and quickly obtained by the increase or
decrease of the entering quantity of gas. The process can be carried out at any
pressure and best at a plus pressure. At the same time it is inmaterial whether
the counter-current be produced directly (as in Fig. 1) or alternately (as in Fig. 2)
by a bi- or poly-division of the system. The gases passing away and containing the
heat of combination may also be employed in another way, for instance, by a
regenerative system for heating the entering gases.
Large apparatus such as are used industrially, work, once the process is in action,
entirely without supply of heat from outside.
The above described method, in contrast with those hitherto known, requires
therefore an installation for heating and a consumption of fuel merely for the starting
of the process.
This means not only a considerable economy of direct expense, but also a
simplification of the apparatus and reduction of wages.

page_text: By this new method sulphur trioxide (sulphurie anhydride) can be manufactured
at so low a price, that it is worth while to transform it into ordinary sulphuric
acid as is obtained by the chamber process and platinum apparatus &c. &c.
The present process represents, therefore a new, and technically important mode of
obtaining sulphur trioxide (s alphuric anhydride) which may be used for making
sulphuric acid in the known manner.
Method for the Manufacture of Sulphur Trioxide (Sulphuric
Anhydride).
I, OLIVER IMRAY, of Birkbeck Bank Chambers, Southampton Buildings, Chancery
Lane, in the County of London, Chartered Patent. Agent, do hereby declare the
nature of this invention (as communicated to me from abroad by The Farbwerke
vormals Meister Lucius & Brüning of Hocchat a/Main, in the Empire of Germany,
Chemical Manufacturers), and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement -
The manufacture of sulphur trioxide (sulphuric anhydride) consists, as is known,
in heating sulphurous anhydride (sulphur dioxide) together with the requisite
oxygen and conducting the hot mixture over or through a contact-body.
The supply of heat required for the reaction, necessitated hitherto the use of
complicated machinery as well as a great amount of fuel.
My correspondents have discovered that this machinery may in great part be
dispensed with, thus enabling a great economy of fuel to be effected, if the
counter current principle or other means be used, so that the heat of combination
set free by the reaction of SO, + 0 =.$0, he employed for heating the entering gas
current.
The following example illustrates one arrangement for utilising the heat of
combination according to this method.
In a counter current apparatus, Figs. 1 and 2 of the drawing accompanying my
provisional specification are first heated to the temperature necessary for the
reaction the entering gases containing SO, & O by a direct supply of heat. As the
mixture passes through the contact substance, oxidation to SO, takes place and con-
sequently the heat of combination is set free.
Thus gases containing SO, and passing away at A from the contact body, have
a much higher temperature than the gases containing SO, entering at E.
The gases containing SO, are then caused to meet those containing SO, and the
considerable fall in the temperature which occurs ensures a transference of heat
from the gases passing away to those entering the contact body.
The equipoise of the process is easily and quickly obtained by the increase or
decrease of the entering quantity of gas.
The process can be carried out at any pressure and best at a plus pressure. At the
same time it is immaterial whether the counter-current be produced directly (as in
Fig. 1) or alternately (as in Fig. 2) by a bi- or poly-division of the system.
The gases passing away and containing the heat of combination may also be
employed in another way, for instance, by a regenerative system for heating the
entering gases.
Large apparatus such as are used industrially, work, once the process is in action,
entirely without supply of heat from outside.

page_text: The above described method, in contrast with those hitherto known, requires
therefore an installation for heating and a consumption of fuel merely for the
starting of the process.
This means not only a considerable economy of direct expense, but also a
simplification of the apparatus and reduction of wages.
By this new method, sulphur trioxide (sulphuric anhydride) can be manufactured
at so low a price, that it is worth while to transform it into ordinary sulphuric acid
as is obtained by the chamber process and platinum apparatus &c. &c.
The present process represents therefore a new, and technically important mode
of obtaining sulphur trioxide (sulphuric anhydride) which may be used for making
sulphuric acid in the known manner.
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 the manufacture of sulphur trioxide (sulphuric anhydride) by the com-
bination of sulphurous anhydride and oxygen, the herein described method of raising
these gases to the temperature required for the reaction, by transferring to them
heat from the produced sulphur trioxide which has a high temperature resulting
from the combining reaction.
Dated this 4th day of July 1000