IMPROVEMENTS IN THE MANUFACTURE OF SULPHURIC ACID, AND IN THE APPARATUS USED THEREIN.
Year: 1871

page_text: LETTERS PATENT to David Jackson, of Lorrimore Road, Walworth,
in the County of Surrey, for the Invention of "IMPROVEMENTS IN
THE MANUFACTURE OF SULPHURIC ACID, AND IN THE APPARATUS USED
THEREIN.
"
Sealed the 3rd October 1871, and dated the 12th April 1871.
PROVISIONAL SPECIFICATION left by the said David Jackson at the
Office of the Commissioners of Patents, with his Petition, on
`the 12th April 1871.
I, DAVID JACKSON, of Lorrimore Road, Walworth, in the County of
Surrey, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE MANUFACTURE OF SULPHURIC ACID, AND IN THE APPARATUS USED
THEREIN," to be as follows:-
The object of my Invention is to simplify the process and apparatus
used in the manufacture of sulphuric acid, dispensing especially with
the leaden chambers usually employed, utilizing and so preventing the
dispersion of the acids of sulphur, azote, and other similar substances
hitherto so noxious to animal and vegetable life, increasing the quantity
and improving the quality of the production, and diminishing generally
the time, labour, and space occupied in the manufacture.

page_text: The apparatus for this system is composed of five distinct parts,
portable, easily mounted, and with equal case dismounted.
First. The furnace for the combustion of the sulphur is composed
of an outer rectangular case of boiler iron, hermetically closed, into
the bottom of which is fitted a shallow pan covering the entire area,
and above this three or moro others at certain distances apart, destined
for the reception and combustion of the sulphur. Between the outer
case and the pans are left spaces, alternately to the right and left, for
the passage of the gases and the overflow of the melted sulphur; over
these is placed the reservoir for the crude sulphur, which is maintained
in a liquid state by the heat of the burning sulphur in the pans below.
The pans are fed from this reservoir by means of a tube communicating
with the pan beneath closed by a plug, on withdrawing which the
liquid sulphur in any desired quantity flows into the said pan and
overflows from this to the next lower one, and so on to the lowermost.
Immediately above the lowermost pan is a perforated plate, through
which is forced by a blowing machine a current of air for the purpose
of supporting and accelerating the combustion of the sulphur. Tho
air is conducted through two or more cast-iron pipes, running parallel
and passing in a serpentine direction over each pan, and becoming in
its passage over the burning sulphur highly heated escapes through the
pierced bottom already mentioned to feed, first, the inferior layer, aud
in succession those lying above, ultimately passing together with the
sulphur vapours through the flue surrounding the reservoir into a large
elbow tube of cast iron, furnished with sorew caps and communicating
with the upper part of the “condenser" or chamber for the deposit of
the sulphur in flour, forming the second part of the apparatus. Tho
condenser is composed of an external rectangular case in wood lined
with sheet iron, or entirely of moderately stout boiler iron hermetically
closed and divided into compartments by means of perforated metallic
or horsehair diaphragms or partitions of gradually diminishing meshes,
leaving alternately above and below a passage for the sulphurous acid
gas and vitiated air; here the gases mechanically mixed with particles of
sulphur in traversing the compartments deposit the sulphur in excess,
and thus several qualities of flour may be collected for commerce.
The gases after passing slowly through this chamber enter through a
leaden pipe into the denitrificator, or third part of the apparatus.
In the case of employing the vapour of arseniferous pyrites or other
metallic sulphurets, I roast the pyrites by any of the ordinary methods,

page_text: and conduct the vapours into a vessel containing water, setting them
free under the water, and causing them to bubble up and pass through
three or four perforated discs, increasing in fineness toward the top and
arranged at short distances from each other under and near the surface
of the water; thus causing them in their passage to abandon the
arsenical acids and other impurities, so that the sulpburous gas and
deoxygenized air alone will, after being freed from its aqueous particles
by passing through a spiral tube, enter into denitrificator. The
denitrificator is formed of a rectangular case in wood and lined
internally with stout sheet lead. The cover is moveable, and when in
operation is hydraulically closed with sulphuric acid contained in a
channel surrounding the four sides of the vessel. The sulphurous
acid gas and nitric acids entering by the leaden tube connected with
the condenser pass over a stratum of sulphuric acid contained in the
bottom and travel in a serpentine direction over a series of plates in
glass, lead, or earthenware slightly inclined alternately in contrary
directions, and escape through a tube communicating with the cylinder
or cylinders of reaction, which tubo terminates in a rose head passing
under the surface of the dilute nitric acid contained therein. The
sulphurous acid gas and nitric acid previous to entering into the
cylinders of reaction combine with a current of air forced by the blowing
machine through the opposite end of the tube supplying the oxygen
necessary for the reactions. The gas purged in its passage through the
condenser and denitrificator, after combining with the pure air, passes
through the rose head of the tube above mentioned, which is immersed to
a short depth in a body of weak nitric acid deposited in the cylinders of
reaction, where it becomes constituted into sulphuric acid, which being a
heavier liquid in its gencration a continual movement of deposition and
ascension will take place and a development of heat ensues.
The
sulphuric acid being deposited in the bottom overflows by the syphon
tube into the dentrificator, where after presenting its surface to the
action of the warm sulphurous acid gas in its passage down the inclined
plates already described falls into a prover furnished with an aerometer,
and thence into a recipient for its final concentration or treatment in the
ordinary manner.
The cylinders of reaction, or fourth part of the apparatus, is composed
of one or more cylinders in earthenware, with dome-shaped cover and
connecting pipes (the number and dimensions to be regulated by the
capacity of the apparatus); they are hydraulically closed at the junctions,

page_text: and at the bottom of oach is a short projecting tube, which is attached
to an articulated pipo in lead, glass, or aluminium, which serves as an
overflow for the sulphuric acid into tho denitrificator. The gases after
gurgling under the pressure of the liquids in the cylinders are distributed
by means of two conically perforated dises in earthonware fitting around
the rose head of the pipo, and at a small distance apart, at or near the
surface of the liquids; through these discs the gases arise and are thus
made to prosent a large superficios to the action of the liquid. In the
romainder of the column, at certain distances, are placed similar discs,
over which is spread a thick layer of light spongy coke or pumice stone
in order to subdivide and commingle the rising gases, oausing them to
fc-act in an atmosphere thus warm and loaded with egcous vapours.
The hyponitrous, azoteous, and oxygen gases escaping from this apparatus
are conducted into the cylinders for the reconstitution of nitric acid, the
fifth and last part of our apparatus. This consists of a series of five or
more cylinders with their connecting pipes similar to those of reaction
of the like material, and with the like perforated dises at intervals for
dispersing the gases. They are arranged each one slightly raised above
the level of the other. Above the series runs a pipe supplying to cach
cylinder a streamlet of pure water, so that the gases mixing with the
water and aqeous vapours pass into the stato of nitric acid more or less
dilute according to the distance traversed. For example, in the first
cylinder we have nitric acid of mediocre strength, in the second and
third gradually weaker, and so on till we arrive at the puro water.
These collectively fall into the cylinders of reaction, and subdividing
fall finally over the surface of the liquid in motion, or rather over the
diaphragms submerged to give place to an infinite series of analogous
decompositions and recompositions.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said David Jackson in the Great Seal Patent Office on 30
the 10th October 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
JACKSON, of No. 43, Lorrimore Road, Walworth, in the County of
Surrey, send greeting.
1

page_text: of our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said David Jackson, Her special licence
that I, the said David Jackson, my executors, administrators, and
assigns, or such others as I, the said David Jackson, 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 MANUFACTURE OF SULPHURIC ACID, AND IN THE APPARATUS USED THEREIN,"
upon the condition (amongst others) that I, the said David Jackson,
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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said David Jackson, do hereby declaro
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement, that is to say :—
The object of my Invention is to improve the process and simplify
the apparatus employed in the manufacture of sulphuric acid, dispensing
especially with the costly leaden chambers and boilers hitherto in usc,
utilizing and so preventing the dispersion of the acids of sulphur,
nitrogen, &c. so prejudicial to animal and vegetable life; by these and
by other means increasing the quantity and improving the quality of
the acid produced, and diminishing generally the time, labour, and space,
and consequently the capital employed in the manufacture.
The theoretical considerations upon which the system is based are the
following:-
Firstly. Each of the three acidical combinations which nitrogen forms
with oxygen is immediately decomposed by sulphurous acid by the
medium of water, from whence ultimately result the deutoxide of
nitrogen and sulphuric acid, more or less aqueous.

page_text: and above this three or more others (f, e, d, &c.) at certain distances
apart, and sustained by transverse iron bars, destined for the reception
and combustion of the sulphur. Between the outer case and the pans
are left apertures (h, h, h,) alternately to the right and left for the
passage of the gases and the overflow of the melted sulphur. Over
these pans is placed the reservoir for the crude sulphur (i), which
is kept in a liquid state by the heat of the burning sulphur in the
pans below. The pans are alimented from the reservoir by means of a
tube (k), which is firmly fixed into the bottom of the same, and elevated
above the level to avoid carrying off the impure deposits; this penetrates
into an iron cup (6) about one-third larger in diameter, which is fixed
upon the bottom of the pan (d) containing the upper strata of sulphur;
this tube is closed by a plug, the handle of which is carried through the
cover of the reservoir, on raising which the liquid sulphur falls from
the reservoir in any desired quantity through the tube into the cup
below, and thence overflows into the pan. As each of the pans, except
the bottom one, has a passage or overflow
at the end toward
the open space of from 3 to 3% inch in depth, as soon as the liquid
sulphur arrives within this distance from the upper edge of the pans
the sulphur overflows into the one below, and so on to the bottom one,
which is the one in the most active state of combustion. Immediately
above the lowermost pan is a perforated plate (a, a,) through which is
forced by a blowing machine a current of air averaging about 85 cube
feet per hour for every pound of sulphur consumed in the same time,
for the purpose of supporting and accellerating the combustion of the
sulphur. This air is conducted through two or more cast-iron pipes
(c, c, c, &c.), passing parallel to each other in a serpentine direction over
cach pan, and in its passage over the burning sulphur becoming highly
heated escapes through the pierced bottom already mentioned to aliment
first the inferior layer, and in succession those lying above, ultimately
passing in combination with the products of combustion through the
flue (j) surrounding the reservoir, escapes by the large elbow tube
of cast iron (g, g,) provided with two openings closed by screw caps,
for the purpose of cleansing it from time to time of the sulphur
5 deposited therein, into the upper part of the condenser or second part of
the apparatus. The combustion of the sulphur in each pan is attended
to from the circular apertures at the end (1, 1, 1, &c.), closed by screw
caps, and which serve on occasion to cleanse them of refuse.

page_text: The condenser (sec Drawings Nos. 1, 2, and 3, Figs. 2,) is composed
of an external rectangular case in wood, lined with sheet iron, or formed
entirely of moderately stout boiler iron, hermetically closed and divided
into compartments by means of perforated metallic or horsehair par-
titions of gradually diminishing meshes, leaving alternately above and
below (H, H, &c.) a passage for the sulphurous acid gas and vitiated
air. Here the gases mechanically mixed with particles of sulphur in
traversing the compartments deposit the sulphur in excess, and thus
several qualities of flour of sulphur may if desired be collected for
commerce, for which purpose an aperture (o) is inserted in the bottom
of each compartment and closed by luted doors. And for the con-
venience of cleaning or visiting the interior a space (V, V,) in the roof
of the condenser is left practicable. The gases passing slowly through
this chamber enter by a leaden pipe into the denitrificator or third part of
the apparatus.
Note. In the case of employing the products of any of the metallic
sulphurets or pyrites they are roasted by any of the ordinary methods,
and the gases conducted into a vessel containing water, setting them
free under the water and causing them to bubble up and pass through
three or four perforated discs, increasing in fineness to the upper one,
and arranged at short distances from each other under and near the
surface of the water, thus causing them in their passage to abandon
the arsenical acids and other impuritics, so that the sulphurous acid gas
and deoxidized air alone will after being freed from the aqueous particles
by passing through a spiral tube enter into the denitrificator.
The denitrificator (sec Drawings Nos. 1, 2, and 3, Figs. 3,) is formed of
a rectangular case in earthenware or in wood, lined internally with stout
sheet lead, earthenware, or glass; the cover (t) is moveable, and when in
operation is hydraulically closed by means of sulphuric acid contained
in a channel surrounding the four sides of the vessel. The sulphurous
acid gas entering by the leaden tube (2) connected with the condenser
passes over a strata of sulphuric acid (9) contained in the bottom, and
travels in a serpeutine direction over a series of plates (r, r, r, &c.) in
glass, lead, or carthenware, slightly inclined alternately in contrary
directions, and escapes through a tube (s) in earthenware, communica-
ting by one or more branches (~,,, &c.) sec Drawings Nos. 1, 2, and 3,
Fig. 4, with the apparatus of reaction, which tubes terminate in a rose
head (,,) passing under the surface of the dilute nitric acid (b').

page_text: The sulphurous acid gas and nitrous acids previous to entering into the
apparatus of reaction combine with a current of air (averaging about
24 cubic feet per hour for every pound of sulphur consumed in the same
time), forced by the blowing machine through the tube (a¹) into the
tube () and supplying the compliment of oxygen required for the
reactions. The gas purged in its passage through the condenser and
denitrificator after combining with the pure air passes through the rose
head of the pipe already mentioned, under the surface of the weak nitric
acid deposited in the chamber of reactions, where it becomes constituted
into sulphuric acid, which being a heavier liquid a continual movement
of ascension and deposition will take place, and a development of heat
ensue, with the production of aqueous vapour favouring the abovo
enunciated reactions. The sulphuric acid as it generates by its superior
weight gravitates to the bottom of the chamber, and so long as the
liquid surpasses a certain height overflows by the syphon tube (u) into
the funnel-shaped pipe (10), and thence into the denitrificator, where
after presenting its surface to the action of the warm sulphurous acid
gas in its passage down the inclined plates already described, and thus
giving up every trace of nitric acid, falls into the prover (x) which is
furnished with an arometer, and thence into the recipient (y) for its
final concentration in the ordinary way.
Note. When the apparatus is upon a very small scale artificial heat
may be necessary to facilitate the process of denitrification, in which
case the denitrificator should be enclosed in a steam case, otherwise the
3 heat generated by the chemical reactions is sufficient.
The apparatus of reactions, see Drawings Nos. 1 and 2, Figs. 4, is
composed of one or more cylinders in earthenware with dome-shaped
covers and connecting pipes (or in the case of very large apparatus of
a rectangular chamber in wood, as hercafter described and figured
Din Drawing No. 3). These cylinders are bydraulically closed at the
junctions, and at the bottom of each is attached an articulated pipe (u)
in lead, glass, or alluminum, which serves as an overflow for the
sulphuric acid into the denitrificator. The gases after gurgling under
the pressure of the liquid in the cylinders or chamber are distributed by
5 means of two conically perforated discs (A, A,) in earthenware, fitting
around the rose head of the pipe from the denitrificator, and at a small
distance apart at or near the surface of the liquid. Through these
dises the gases arise, and are thus made to present a large superficies to

page_text: the action of the liquid. In the remainder of the chambers or cylinders
at certain distances are placed similar discs (A, A,) over which is spread
a thick strata of light coke or pumice stone in order to subdivide and
commingle the rising gases, causing them to react in an atmosphere
thus warm and loaded with aqueous vapours.
The gases arising from the cylinders of reaction are conducted by the
pipes (F, F, &c.) into the apparatus for the reconstitution of nitric acid,
the fifth and last part of the apparatus, see Drawings Nos. 1 and 2,
Figs. 5. This consists of a series of cylinders similar to those of re-
action (the number and dimensions of which are to be regulated by the
requirements) with their connecting pipes, forming a continuous com-
munication from the summit of one to the base of the other; or, as
already mentioned, in the case of very large apparatus where the
apparatus of reactions is formed of a rectangular chamber in wood, the
reconstitution of nitric acid is effected by giving an increased height to
this chamber so as to afford ample time for the gases in their upward
passage through the perforated plates to commingle and combine with
the water discharged in a fine shower from the summit of the chamber,
as hereafter described and shewn in Drawing No. 3.
Perforated discs are distributed at certain distances in the interior,
upon which is spread a strata of coke or pumice stone. The cylinders
are raised each one slightly above the level of the other, and over the
series runs a pipe (c¹), supplying to cach cylinder a streamlet of pure
water, in quantity altogether about one half more by weight than the
sulphur consumed.
In each of the cylinders there will be found nitrous acid gas, oxygen
in quantity greater than that required by the nitrous acid to pass into
nitric acid, and water in excess. These gases mixed with the water
and aqueous vapours generated by the chemical reactions pass into the
state of nitric acid more or less dilute. In the first cylinder we have a
nitric acid of mediocre strength, in the second and third gradually
weaker, and so on till we arrive at pure water. These collectively fall
through the tubes (e, c, e, &c.) in glass or alluminum into the
cylinders of reaction, and subdividing fall finally over the surface of
the liquid in motion, or rather over the diaphragms submerged to give 3
place to an infinite series of analogous decompositions and recom-
nositions

page_text: Similar reactions will evidently take place in the case of combining
the 4th and 5th parts of the apparatus in one chamber, as shewn in
Drawing No. 3, Fig. 4.
INSTRUCTIONS FOR WORKING THE APPARATUS.
Commence by filling the prover (a), into which is inserted the dis-
charging tube of the denitrificator (Fig. 3) with sulphuric acid of the
density of about 170, and with the like acid the cover of the deni-
trificator (t) is hydraulically closed. Pour also into the cylinders or
chamber of reaction (Fig. 4) weak nitric acid of the density of about
116 until the rose head of the pipe conducting the gases from the
denitrificator is immersed two or three inches in the liquid. Otherwise
two-thirds of sulphuric acid of sp. gr. 1.70 may be first poured in, and
the remainder filled up with weak nitric acid, so that it floats. The
cylinders and tubes, as well those of reaction as those for the reconstitu-
tion of nitric acid, are hydraulically closed at their junctions simply with
water. The combustion being commenced in the various stages of
sulphur in the furnace, the blowing machine is put into motion, the
gas purged in its passage through the condenser and denitrificator
passes into the cylinders or chamber of reactions, where gurgling in the
nitric acid it is forced by the means already explained to continue under
the action of the said acid until constituted into sulphuric acid, which
being a heavier liquid a continual movement of ascension and deposition
will take place, at the same time a development of heat ensues, be it by
the ulterior combustion of sulphurous acid gas, by the passage of the
gascous bodies into the liquid state, or by the combination of anhydrous
sulphuric acid with water, the consequence is a production of aqueous
vapour moderated by the heating of a current of nitrogen and of
atmospheric air, as well as by the lowering of the temperature owing to
decomposition of nitric acid, altogether forming conditions under which
the reactions above enunciated cannot fail.
In order to shew the relative proportions of the apparatus the
accompanying Drawings, Nos. 1 and 2 (vertical section and ground
plan) are figured with the dimensions calculated for the production per
day of 24 hours of three tons of sulphuric acid of the specific gravity of
1.846. Thus given the daily combustion of one ton = 2,240 lbs. of
sulphur, which united to 3,300 lbs. of atmospheric oxygen will constitute
5,600 lbs of sulphuric acid anhydrous. We shall consume 1,260 lbs. of

page_text: water for the sulphuric acid monohydrate, and about the one-third of
(5,000+1,200) = 2,287 lbs. of water to constitute it to the sp. gr. 1-75,
therefore we require 1,200 + 2,287 = 3,547 lbs., or 355 gallons of
water per 24 hours continuously. If then we discharge incessantly into
the apparatus of reaction about 4,000 cubic inches per hour of nitric
acid of about the sp. gr. of 1·16, as reconstituted by our apparatus, and
if the blowing machine discharge 10,000 cubic feet of air per hour, that
is to say, 7,800 cubic feet for the combustion of sulphur, and 2,200
cubic feet for the oxidation of the gases which pass into the cylinders or
chamber of reactions, and a stream of water of about 2rd cubic feet
per hour bo distributed in the apparatus for the reconstitution of nitric
acid, the tubes acting as overflow would discharge 325 lbs. per hour, or
7,800 lbs. per day of 24 hours, of sulphuric acid of the density of about
1.75 into the denitrificator, and from thence into the recipient for its
final concentration in platina.
In the case of large apparatus, say for the daily combustion of any
quantity of sulphur from one ton and upwards, as the employment of
earthenware cylinders would then from their increased number and
dimensions become complicated and otherwise objectionable, I purpose
a modification of the fourth and fifth parts of the apparatus already
described, namely, that of reactions, and that for the reconstitution of
nitric acid by uniting them in one chamber, sec Drawing No. 3, Fig. 4.
The entire Drawing shews the arrangement with figured dimensions of
an apparatus for the combustion, &c. of five tons of sulphur per day of
24 hours, and of which the following is a description :-Figs. Nos. 1,
2, and 3 are constructed as already described; Fig. 4 (a), a horizontal
pipe running over the denitrificator and parallel with the side of the
chamber of reactions, to which are connected at distances of about 3 fect
apart and at right angles the tubes (=,=,=, &c.) terminating in a rose
head and conveying the gases under the surface of the dilute nitric acid
in the chamber. (b, b, b, b,) a section of the chamber constructed
in compartments (c, c, c, &c.) hydraulically closed at the junctions.
by stout leaden channels
232
or simply, as there is no pressure to
overcome, by slightly bevelling the surface of the junctions inwards
It must be about 35 feet high, and 3 ft. 3 in. wide, and furnished at

page_text: intervals with perforated plates in carthenware (1, 1, 1, &c.) to subdivide
and commingle the rising gases; it is composed of stout oaken plank,
slightly carbonized on the inner surface and paid over with a thick coat
of a composition of finely powdered shellac and a solution of caoutchouc
in coal naptha mixed whilst warm (this composition as well as some
others which might be named will withstand the action of the acids,
and. will bear without alteration a degree of heat far superior to that
engendered by the reactions, it is highly adhesive to wood, glass,
carthenware, &c., and moderately inexpensive,) thus forming a perfect
substitute for the carthenware cylinders. About 10 feet length of this
section will be necessary for every ton of sulphur consumed per day.
The lower portion of the chamber (e, f, g,) for the reception of the diluto
nitric acid is lined with earthenware slabs, these are laid on whilst warm
and thus become by the intervention of the above-named composition
firmly cemented to the wood, and the joints throughout are well secured
with the like cement. (h) short open tubes placed at intervals, at the
bottom of which runs a minutely perforated channel in earthenware the
whole length of the chamber for the reception of the water supplied
from the cistern (/), causing it to descend into the chamber in a
minutely divided state for its ready combination with the gases. (m)
vertical fixed supports at necessary intervals to sustain the chamber.
FINIS