Improvements in Process and Apparatus for the Manufacture of Chlorine.
Year: 1894

page_text: '
Date of Application, 21st Aug., 1894
Complete Specification Left, 21st May, 1895-Accepted, 17th Aug.,
1895
PROVISIONAL SPECIFICATION.
Improvements in Process and Apparatus for the Manufacture
of Chlorine.
We, SAMUEL ALEXANDER SADLER and ROBERT HUTTON WILSON, both of
The Cleveland Chemical Works Middlesbrough, in the County of York,
Manufacturing Chemists, do hereby declare the nature of this invention to be
as follows:
This invention consists of a combination and an arrangement of plant and
apparatus for the manufacture of chlorine by the decomposition of hydrochloric
acid by nitric acid in the presence of sulphuric acid, whereby chlorine is con-
tinuously and regularly evolved, and the liquid products of decomposition are
dealt with simultaneously so as to form a continuous process which is more rapid
economical and efficient than anything that has hitherto been done; and by which
the reactions are so complete that practically pure chlorine is obtained, and the
resulting acid liquor is free from nitric acid or nitrogen oxides as well as hydro-
chloric acid or other chlorine compounds, a result which has never before been
achieved by anyone on a commercial scale.
Our invention consists:-
1. Of mechanical contrivances, and appliances by which the three acids are
exactly measured in the required, proportions and automatically fed into the
process, and also by which the resulting hot dilute sulphuric acid is directly lifted
into a concentrating pan, placed at such a height that the acid can flow back hot
into the process or the effluent dilute sulphuric acid may run. direct into a
concentrating.pan from which it may be, lifted by the same means and returned
to the process.
2. Also of decomposing vessels, columns or chambers, constructed as follows:-
A long preferably. rectangular, closed vessel is built of well burnt clay, slabs,
quarls, bricks or stone flags which dovetail or overlap each other, jointed, with
asbestos cement and encased with strong sheet lead, the lead being protected inside
with a coating or thin layer of sulphate of lead cement, or..other suitable acid
resisting cement, or the decomposer may be constructed of stone flags, with the
bottom a solid block, scooped or hollowed out to a sufficient depth to contain the
acids so that they do not reach the joint forming the sides.
Cross divisions of brick, stone or other suitable material, are so arranged as to
prolong the flow of liquid through the vessel.
Inside the decomposer, coils of lead pipe are placed, which are heated by, steam
or hot air sufficiently to energetically boil the contents, and which coils are so
arranged that the degree of heating can be increased or diminished in any portion
or part of the said decomposer.
Orifices are made in the top of the decomposer for thermometers and pressure
gauges whereby the process is regulated.
To insure a perfect mixture of the acids on entering the decomposer we have
constructed a receiver of earthenware or glass, which is placed at one end of
decomposer into which the three acids flow and thence overflow in cascades into
several trays one below the other.
Or, the three acids may be poured or injected into vessels as described, for
securing intimate mixture, placed in the head or top of a column or tower

page_text: constructed of stone, burnt clay blocks, or other refractory material which will
resist these acids. The column is packed with suitable material that will distribute
and divide the combined liquids over a large surface and cause them to flow
slowly down, to allow sufficient time for the hot steam and gases evolved by an
arrangement at the bottom of the tower, for boiling violently the descending
liquid which form into a pool in the base or basin at the bottom of the tower or
column.
Or the acids may be run directly into such a tower.
The tower may be enclosed with lead.
The evolved gases are conducted, first, through a dephlegmating column or
scrubber which returns any suspended or easily condensible liquid down which, if
desired as an alternative process the three acids may be automatically measured
into the process and in any case then into earthenware condensers placed' hori-
zontally or vertically cooled by being placed in water or by having water sprayed
over the surface or by air cooling or partly by air and partly by water cooling.
Condensing arrangement is fixed at such an elevation that the condensed fluids
comprising nitrous, nitric and chlorine compounds, water etc., can go back to the
decomposer preferably by the same channel as that by which the gases came
from it.
The cooled gases are then passed through a suitably packed tower or towers so
placed that the same machinery which is used to feed the decomposer can be
employed to automatically supply sulphuric acid to the top of them, in the exact
quantities required to absorb the nitrous acid gas which is mixed with the chlorine.
This mechanical contrivance being geared to the same shaft as regulates the
feed in the decomposer, it follows, that if the rate of decomposition is accelerated
or retarded the feed of sulphuric acid to the top of the tower is regulated
precisely thereto.
Suitable covered tanks at an elevation receive the nitrous vitriol which is
afterwards denitrated by steam and air in the usual well known manner; the nitric
acid recovered being used over again in the process.
The chlorine gas passes forward into another tower or towers down which
water is also automatically, and only in required quantity, fed from the same
shafting as before mentioned, to wash out any hydrochloric acid which may be
mixed with the chlorine. This hydrochloric acid flows directly back into the
hydrochloric feed cistern.
The chlorine gas is then conducted to the usual lime absorbing chambers and
converted into bleaching powder, the chlorine gas being practically pure and
unmixed with air or other diluent gases produces bleaching powder more readily
and stronger than is the case with other processes, whilst for the production of
liquid chlorine it has very special advantages, as well as also for the manufacture
of chlorates, hypochlorites, chlorites etc.
In the accompanying drawings :-
A is the decomposer or still, built of acid resisting material and encased with
lead.
a a is a sectional plan of the decomposer shewing internal arrangement F F
being two steam coils.
A, A, A, shew divisions to prevent liquid flowing too fast through the
vessel.
W is the main shaft driveu by steam or other motive power.
Driven from the shaft W is a rocking shaft B, passing through the upper part of
vessels containing nitric acid (which is supplied from tank HN.O, by syphon Sy),
hydrochloric acid (which is supplied from tank H.Cl by syphon Sy,) and
sulphuric acid, the sulphuric acid vessel C being directly connected by channel M M
with the acid evaporating pan J.
On the shaft B are placed cups d' d' d³ in the case of nitric acid d¹ of earthen-
ware, and of sulphuric acid d³ of lead, of hydrochloric acid d' either earthenware
or gutta percha, the capacity of these cups being adjusted to lift the required

page_text: quantities of acids which flow into the small vessel E, where they mix and overflow
as described.
His the outlet through which the effluent hot acid runs into the apparatus I
which is a revolving series of cups on arms of sufficient length to raise the acid
high enough to flow into the acid evaporating pan J, at the point K. The acid
evaporating pan is divided by cross partitions so that the weak acid does not reach
the front or hottest part of the pan until it is concentrated; it then flows out at
the point L into the channel M M leading to the feed cistern C.
N' is an earthenware pipe which conducts the gases to the cooling system 0000.
The first column is preferably made of stone packed so as to be a dephlegmator;
the other part of cooler is constructed of earthenware or other acid resisting pipes,
which are either placed in a large tunk containing water, or are water jacketed, or
are cooled by a spray of water trickling down them as shewn in the drawing. P is
the sulphuric acid absorbing tower for the extraction of the nitrous acid, the
nitrous vitriol flowing out into the receiving tank R placed at such an elevation
that it will run direct into the denitrating apparatus by the pipe ✗.
S is a second or water tower properly packed for washing out from the gas any
hydrochloric acid, which flows direct from the bottom of the tower to the hydro-
chloric feed vessel C, or into the decomposer C..
Y is a rocking shaft on which is cup for feeding the sulphuric acid from
cistern Z to tower P. Y, is a rocking shaft with cup for feeding water to tower S.
These rocking shafts, also the elevator I are all connected to and worked by the
main shaft W.
V is the outlet for the practically pure chlorine gas available either for the
manufacture of bleaching powder, liquid chlorine, chlorates or any other chlorine
compound.
Dated this 18th day of Avơust. 1894
Improvements in Process and Apparatus for the Manufacture of
Chlorine.
We, SAMUEL ALEXANDER SADLER, and ROBERT HUTTON WILSON, both of
The Cleveland Chemical Works, Middlesbrough, in the County of York,
Manufacturing Chemists, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:—
This invention consists of a combination and an arrangement of plant and
apparatus for the manufacture of chlorine by the decomposition of hydrochloric
acid by nitric acid in the presence of sulphuric acid, whereby chlorine is
continuously and regularly evolved, and the liquid products of decomposition are
dealt with simultaneously so as to form a continuous process which is more rapid
economical and efficient than anything that has hitherto been done; and by which
the reactions are so complete that practically pure chlorine is obtained, and the
resulting acid liquor is free from nitric acid or nitrogen oxides as well as hydro-
chloric acid or other chlorine compounds, a result which has never before been
achieved by anyone on a commercial scale.
Our invention consists :-
1. Of mechanical contrivances and appliances by which the three acids are
exactly measured in the required proportions and automatically fed into the
process, and also by which the resulting bot dilute sulphuric acid is directly lifted
into a concentrating pan, placed at such a height that the acid cau flow back hot
into the process or the effluent dilute sulphuric acid may run direct into a

page_text: concentrating pan from which it may be lifted by the same means and returned to
the process.
2. Also of decomposing vessels, columus or chambers, constructed preferably as
follows:-
A long preferably rectangular, closed vessel is built of well burnt clay slabs,
quarls, bricks or stone flags which dovetail or overlap each other, jointed with
asbestos cement and encased with strong sheet lead, the lead being protected inside
with a coating or thin layer of sulphate of lead cement, or other suitable acid
resisting cement, or the decomposer may be constructed of stone flags, with the
bottom a solid block, scooped or hollowed out to a sufficient depth to contain the
acids so that they do not reach the joint forming the sides.
Cross divisions of brick, stone or other suitable material, are so arranged as to
prolong the flow of liquid through the vessel.
Inside the decomposer, coils of lead pipe are placed, which are heated by steam
or hot air sufficiently to energetically drive off the gas, and which coils are so
arranged that the degree of heating can be increased or diminished in any portion
or part of the said decomposer.
Orifices are made in the top of the decomposer for thermometers and pressure
gauges whereby the process is regulated.
To insure a perfect mixture of the acids on entering the decomposer we have
constructed a receiver of earthenware or glass, which is placed at one end of
decomposer into which the three acids flow and thence overflow in cascades into
several trays one below the other.
The evolved gases are conducted, first, through a dephlegmating column or
scrubber which returns any suspended or easily condensible liquid. Then into
earthenware or glass condensers placed horizontally or vertically, cooled by being
placed in water or by having water sprayed over the surface or by air cooling or
partly by air and partly by water cooling.
Condensing arrangement is fixed at such an elevation that the condensed fluids
comprising nitrous, nitric and chlorine compounds, water etc., can go back to the
decomposer preferably by the same channel as that by which the gases came
from it.
The cooled gases are then passed through a suitably packed tower or towers so
placed that the same machinery which is used to feed the decomposer can be
employed to automatically supply sulphuric acid to the top of them in the exact
quantities required to absorb the nitrous acid gas which is mixed with the chlorine.
This mechanical contrivance being geared to the same shaft as regulates the feed
in the decomposer, follows, that if the rate of decomposition is accelerated or
retarded the feed of sulphuric acid to the top of the tower is regulated precisely
thereto.
Suitable covered tanks at an elevation receive the nitrous vitriol which is after-
wards denitrated by steam and air in the usual well known manner; the nitric acid
recovered being used over again in the process.
The chlorine gas passes forward into another tower or towers down which water
is also automatically, and only in required quantity, fed from the same shafting as
before mentioned, to wash out any hydrochloric acid which may be mixed with the
chlorine. This hydrochloric acid flows directly back into the hydrochloric feed
cistern.
The chlorine gas may then be conducted to the usual lime absorbing chambers
and converted into bleaching powder, the chlorine gas being practically pure and
unmixed with air or other diluent gases produces bleaching powder more readily and
stronger than is the case with other processes, whilst for the production of liquid
chlorine it has very special advantages, as well as also for the manufacture of
chlorates, hypochlorites, chlorites, etc.
•
In the drawings accompanying our Provisional-Specification:
A is the decomposer or still, built of acid resisting material and encased

page_text: a a is a sectional plan of the decomposer showing internal arrangement,.
FF being 2 steam coils; or preferably we provide a separate steam coil in each.
section of the decomposer.
A', A', Ashew divisions to prevent liquid flowing too fast through the vessel
they compel the liquid to traverse in succession each section into which they divide
the floor of the decomposer so that no part of the liquid can pass directly from the
inlet to the outlet, so the liquid is retained until practically nothing remains in a
liquid state but dilute sulphuric acid.
W is the main shaft driven by steam or other motive power.
Driven from the shaft W is a rocking shaft B, passing through the upper part
of vessels containing nitric acid (which is supplied from tank HN.O, by syphon Sy),
hydrochloric acid (which is supplied from tank H.C1 by syphon Sy₂) and sulphuric
acid, the sulphuric acid vessel C being directly connected by channel M M with the
acid evaporating pan J.
Ou the shaft B are placed cups d' d² d³, in the case of nitric acid d' of
earthenware, and of sulphuric acid d³ of lead, of hydrochloric acid d either
earthenware or gutta percha, the capacity of these cups being adjusted to lift the
required quantities of acids which flow into the small vessel E, where they mix and.
overflow as described.
H is the outlet through which the effluent hot acid runs into the apparatus I
which is a revolving series of cups on arms of sufficient length to raise the acid:
high enough to flow into the acid evaporating pan J at the point K. The acid
evaporating pan is divided by cross partitions so that the weak acid does not reach
the front or hottest part of the pan until it is concentrated; it then flows out at the:
point L into the channel M M leading to the feed cistern C.
N is an earthenware pipe which conducts the gases to the cooling system 0000..
The first column is preferably made of stone, packed so as to be a dephlegmator, the
other part of cooler is constructed of earthenware or other acid resisting pipes,.
which are either placed in a large tank containing water or are water jacketted, or
are cooled atmospherically only or by a spray of water trickling down them as.
shewn in the drawing. P is the sulphuric acid absorbing tower for the extraction
of the nitrous acid, the nitrous vitriol flowing out into the receiving tank R placed
at such an elevation that it will run direct into the denitrating apparatus by the
pipe X.
S is a second or water tower properly packed for washing out from the gas any
hydrochloric acid, which flows direct from the bottom of the tower to the hydro-
chloric feed vessel C, or into the vessel C, within the decomposer.
Y is a rocking shaft on which is cup for feeding the sulphuric acid from cistern Z.
to tower P. Y, is a rocking shaft with cup for feeding water to tower S. These
rocking shafts, also the elevator I, are all connected to and worked by the main
shaft W.
V is the outlet for the practically pure chlorine gas available either for the
manufacture of bleaching powder, liquid chlorine, chlorates or any other chlorine
compound.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. For the manufacture of chlorine, mixing nitric and hydrochloric acid and
sulphuric acid within a decomposer or column or still, and in the same vessel
heating the mixed acids by steam or hot air pipes immersed therein, thereby
driving off the chlorine generated and other accompanying gases and vapours.
2. For the manufacture of chlorine, a decomposer provided with partitions and
suitably heated and arranged so that the acids as they traverse the decomposer are
progressively freed from chlorine and other gases and vapours and so that the
liquid from which the gases and vapours have been separated is prevented from.

page_text: again mixing with the liquid which has not been so freed from gases and
vapours.
i
3. For the manufacture of chlorine a decomposer constructed substantially as
- described of stone or burnt clay of like slabs with or without a leaden casing or with
the bottom in one piece without joint below the level of the liquid.
4. For the manufacture of, chlorine, the method by which the operation is
rendered continuous viz., by the use of a series of mechanical feeders so driven by
a line of shafting or otherwise as to operate in unison and supply in due relative
proportions the different liquids required to the several parts of the apparatus.
5. For the manufacture of chlorine, apparatus consisting of a decomposer, a
mechanical lifter, and an evaporating pan so arranged that the sulphuric acid
having absorbed water in the decomposer is concentrated and returned into the
d'ecomposer.
6. For the manufacture of chlorine, apparatus consisting of a decomposer in
which the mixed acids are decomposed and chlorine and other gases and vapours
are evolved, a cooler by which the gases are cooled, and vapour condensed and
passed back into the decomposer, a tower, or like suitable apparatus, by which the
cooled gases are washed with sulphuric acid and nitrous gas removed and a tower or
like apparatus by which the chlorine gas is washed with a small quantity of water
and the resulting hydrochloric acid returned to the decomposer.
7. The combination of apparatus substantially as described and represented in
the annexed drawings.
1005