IMPROVEMENTS IN THE MANUFACTURE OF SULPHURIC ACID.
Year: 1882

page_text: LETTERS PATENT to Walter Weldon of Rede Hall Burstow, in the County of
Surrey, for an invention of IMPROVEMENTS IN THE MANUFACTURE OF
SULPHURIC ACID. A communication from the Société de la Manufacture de
Javel, a firm of Chemical Manufacturers at Paris.
PROVISIONAL SPECIFICATION left by the said Walter Weldon at the Office
of the Commissioners of Patents on the 13th April 1882.
WALTER WELDON, of Rede Hall, Burstow, in the County of Surrey, IMPROVE-
MENTS IN THE MANUFACTURE OF SULPHURIC ACID-A Communication from the
Société de la Manufacture de Javel, a firm of Chemical Manufacturers at Paris,
This invention relates to the manner of introducing into the apparatus einployed
in the manufacture of sulphuric acid the nitrous compounds employed in that
manufacture. Sulphuric acid is manufactured by means of an apparatus consisting
of a series of lead chambers, to which is appended what is known as a Gay-Lussac
tower. It is the universal custom at present to introduce the whole of the nitrous
compounds employed into the first of the series of lead chambers; but my cor-
respondents have found that considerable economies may be effected by introducing
the nitrous compounds at several points of the apparatus, instead of at one only, as
at present. Their invention accordingly consists, firstly, in substituting for the
present method of introducing the whole of the nitrous compounds into the first
chamber, the method of introducing only a portion of them into the first chamber
and then introducing either a further portion of them into a subsequent chamber
or further portions of them into subsequent chambers; and, secondly, in further
introducing a small proportion of nitrous compounds at the top of the Gay-Lussac
tower.
When, as is invariably the case at present, the whole of the nitrous compounds
employed is introduced into the first lead chamber, the temperature of the contents
of the said first chamber is apt to become elevated to a point at which reactions
take place which result in the reduction of some of the nitrous compounds to the
state of protoxide of nitrogen, or even of free nitrogen; and at the same time the
.

page_text: temperature of the subsequent chambers is apt to bo too low to permit of the
required reactions taking place in them with satisfactory rapidity. Moreover,
certain compounds which are always present in the gases which leave the chambors
asca pe absorption in the Gay Lussac tower. But by distributing the nitrous com-
pounds according to the modified manner of introducing them which constitutes
the invention of my correspondents, all these disadvantages are avoided. There is
no reduction of nitrous compounds in the first chamber to a state in which they
cannot be reoxidized. The work of the subsequent chambers is rendered moro
active. And the escape of nitrous compounds and of sulphurous acid from the Gay
Lussac tower is almost entirely prevented. The present invention thus enables a
largely increased quantity of sulphuric acid to be manufactured per given capacity
of apparatus employed, and at the same time greatly diminishes the loss both of
nitrous compounds and of sulphurous acid which manufacturers of sulphuric aci<l
invariably incur at present.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Walter Weldon in the Great Seal Patent Office on the 12th October
1882.
WALTER WELDON, of Redo Hall, Burstow in the County of Surrey, "IMPROVE-
MENTS IN THE MANUFACTURE OF SULPHURIC ACID," A Communication from the
Société de la Manufacture de Javel, a firm of Chemical Manufacturers at Paris.
This invention relates to the manner of introducing into the apparatus employed
in the manufacture of sulphuric acid the nitrous compounds employed in that
manufacture. Sulphuric acid is manufactured by means of an apparatus consisting
of a series of lead chambers, to which is appended what is known as a Gay Lussac
tower. It is the universal custom at present to introduce the whole of the nitrous
compounds employed into the first of the series of lead chambers; but my cor-
respondents have found that considerable economics may be effected by introducing
the nitrous compounds at several points of the apparatus, instead of at one only, as
at present. Their invention accordingly consists, firstly, in substituting for the
present method of introducing the whole of the nitrous compounds into the first
chamber, the method of introducing only a portion of them into the first chamber,
and then introducing either a further portion of them into a subsequent chamber
or further portions of them into subsequent chambers; and, secondly, in further
introducing a small proportion of nitrous compounds at the top of the Gay Lussac
tower.
When, as is invariably the case at present, the whole of the nitrous compounds
employed is introduced into the first lead chamber, the temperature of the contents
of the said first chamber is apt to become elevated to a point at which reactions
take place which result in the reduction of some of the nitrous compounds to the
state of protoxide of nitrogen, or even of free nitrogen; and at the same time the
temperature of the subsequent chambers is apt to be too low to permit of the
required reactions taking place in them with satisfactory rapidity. Moreover,
certain compounds which are always present in the gases which leave the chambers
escapo absorption in the Gay Lussac tower. But by distributing the nitrous com-
pounds according to the modified manner of introducing them which constitutes the
invention of my correspondents, all these disadvantages are avoided. There is no
reduction of nitrous compounds in the first chamber to a state in which they cannot
be reoxidized. The work of the subsequent chambers is rendered more active.
And the escape of nitrous compounds and of sulphurous acid from the Gay Lussac
tower is almost entirely prevented. The present invention thus enables a largely
increased quantity of sulphuric acid to be manufactured per given capacity of
apparatus employed, and at the same time greatly diminishes the loss both of
nitrous compounds and of sulphurous acid which manufacturers of sulphuric acid
invariably incur at present.
What is claimed as the invention protected by the herein-before in part recited
Letters Patent is as follows:
First. Distributing the nitrous compounds employed in the manufacture of sul-
phuric acid by introducing only a portion of them into the first of the series of
chambers employed, and introducing either another portion or other portions of
them into a subsequent chamber or into one or more subsequent chambers.

page_text: Second. Feeding the Ciny Lussac towers employed in the manufacture of sul-
phuric acid with sulphuric acid having dissolved in it a slight proportion of nitrous
compounds.
In witness whereof I, the said Walter Weldon, have hereunto set my band
and seal this eleventh day of October in the year of Our Lord One thousand
eight hundred and eighty two.
WALTER WELDON. (L.S.)