IMPROVEMENTS IN THE MANUFACTURE OF SULPHURIC ACID
Year: 1861

page_text: LETTERS PATENT to Peter Ward, of 2, Clouds Hill Villas, Bristol, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF SULPHURIC ACID."
Sealed the 16th October 1861, and dated the 23rd April 1861.
PROVISIONAL SPECIFICATION left by the said Peter Ward at the Office
of the Commissioners of Patents, with his Petition, on the 23rd April
1861.
I, PETER WARD, of 2, Clouds Hill Villas, Bristol, do hereby declare the
nature of the Invention for "IMPROVEMENTS IN THE MANUFACTURE OF SUL-
PHURIC ACID," to be as follows:-
This Invention has for its object improvements in the manufacture of:
sulphuric acid. For this purpose a large extent of surface of glass
or other
material on which the acid has no - action is arranged in the leaden chamber3
used in the manufacture of sulphuric acid. The glass or other material is
employed either in the form of sheets, tubes, or otherwise, so as to expose a
great extent of surface in contact with the mixed sulphurous and nitrous gases, :
and the surfaces are kept moistened with acid. This arrangement greatly
accelerates the formation of sulphuric acid from the mixed gases.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Peter Ward in the Great Seal Patent Office on the 23rd
October 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PETER
WARD, of 2, Clouds Hill Villas, Bristol, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of April, in the year of our Lord
One thousand eight hundred and sixty-one, in the twenty-fourth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Peter Ward, Her special licence that I, the said Peter Ward, my
executors, administrators, and assigns, or such others as I, the said Peter
Ward, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE MANUFAC-
TURE OP SULPHURIC ACID," upon the condition (amongst others) that I, the said
Peter Ward, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should particularly describe
and ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of the
said Letters Patent.
NOW KNOW YE, that I, the said Peter Ward, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
This Invention has for its object improvements in the manufacture of
sulphuric acid. For this purpose a large extent of surface of glass or other
material on which the acid has no action is arranged in the leaden chambers
used in the manufacture of sulphuric acid. The glass or other material is
employed either in the form of sheets, tubes, or otherwise, so as to expose a
great extent of surface in contact with the mixed sulphurous and nitrous gases,
and the surfaces are kept moistened holding a film of acid. This arrangement
greatly accelerates the formation of sulphuric acid from the mixed gases.
And in order that my said Invention may be most fully understood and
readily carried into effect I will proceed to describe the method in which I
prefer to conduct the manufacture.

page_text: The sulphurous and nitrous gases, obtained as heretofore, I cause to pass,
first into a mixing chamber formed, by preference, of lead; this chamber may
be of much smaller dimensions than the leaden chambers heretofore employed;
for example, if the burners are of a size to burn 140 cwt. of sulphur pyrites in
24 hours, the mixing chamber may conveniently be made of the following
dimensions, viz., 64 feet long, 16 feet high, and 20 feet wide; here the gases
become mixed. In this chamber steam is introduced and some acid is con-
densed, as heretofore. From the mixing chamber the gases remaining uncon-
densed pass into a second chamber, also made of lead; and (for burners of the
dimensions stated) about 200 feet long by 3 feet high and 3 feet wide; the
bottom of this chamber should be divided into four equal parts to allow of the
acid being run off separately. Within this chamber sheets of glass are
arranged horizontally and parallel the one to the other at a distance. of .about
an inch apart. The sheets of glass are supported one over the other on strips
of glass or earthenware supports until the pile reaches to the top of the
chamber. The sheets may be of any convenient length, and are in each layer
placed end to end until the layer extends to a distance of, say, 25 feet. The
cover of the chamber may be made in sections, so that it may readily be
removed for convenience of access to the glass. It will be seen that the
portion of the chamber thus filled with the pile of glass is by it divided into a
series of narrow passages running the whole length of the pile, and through
which the gases are compelled to pass. At the end of the first pile a space is
left in the chamber about 4 feet in length to allow the gases again to mix
freely, and then another pile of glass, similar to the first, is formed, and in this
way the chamber is filled, the piles of glass and mixing spaces occurring alter-
nately at equal distances apart. Steam is introduced into the second chamber
at the end next to the first chamber, and in quantity sufficient to produce acid
of from 1 675 to 1'750 specific gravity in the farthest or last division of the
second chamber. This acid will be found to have condensed with it a con-
siderable quantity of nitrous acid and nitric oxide; it is run back into the
leaden trough leading from the burners to the first chamber, where, by the
action of the sulphurous gas and steam it is deprived of its nitrous acid and
nitric oxide. In place of sheets of glass tubes of about an inch in diameter
may conveniently be employed, the tubes being laid horizontally and longi-
tudinally within the chamber, so as to produce piles as before. The glass
employed should contain as little alkali as possible, otherwise it will be slowly
acted on by the acid. If the draft through the chambers to the chimney is
weak, so that it would be injuriously checked by the arrangements berein-
before described, the sheets of glass may be placed at greater distances apart;

page_text: .or if tubes be employed they may be made larger in diameter; the greater
-the extent of surface, however, introduced, into the chamber the greater the
advantage obtained so long as the draft is not injuriously checked, the exposed
surfaces tending to accelerate the chemical changes and facilitate the conden-
sation of the acid. The quantity of steam introduced into the second chamber
should be carefully regulated within the limits stated, as, if less be introduced,
the acid will be liable to form, in cold weather, a crystalline mass, filling up
the passages and retarding the draft; and if the quantity of steam is largely
increased, the quantity of acid obtained from a given quantity of pyrites will
be less, and a loss of nitrous acid and nitric oxide will also result.
By the improvements herein-before described the following advantages will
be obtained... A greater quantity of acid may be manufactured in a given
space. A greater quantity of acid may be manufactured from a given
quantity of pyrites or sulphur. A much smaller quantity of nitrate of soda
will be required than heretofore. The wear and tear of the chambers will be
reduced.
In witness whereof, I, the said Peter Ward, have hereunto set my hand
and seal, this Eighteenth day of October, in the year of our Lord
One thousand eight hundred and sixty-one.
PETER WARD. (L.S.)