An Improved Apparatus for the Manufacture of Salt
Year: 1895

page_text: Date of Application, 19th Oct., 1895
Complete Specification Left, 17th July, 1896-Accepted, 12th Sept., 1896
PROVISIONAL SPECIFICATION
An Improved Apparatus for the Manufacture of Salt
I ALFRED ROLAND DAVIS of 32 Blackfinars Street Manchester Chemical
Engineer do hereby declare the nature of this invention to be as follows
-
This invention has reference chiefly to the manufacture of sodium chloride or
common salt from bune, but it is also applicable to the manufacture of any other
kind of salt which can be made to separate out in a granular form from its aqueous
solution by concentration
The improved apparatus consists of three distinct parts: -(1) a furnace in which
coal or other fuel can be economically burned and which is so constructed as to
include a combustion chamber or other arrangement for securing a smokeless
flame; (2) an evaporating chamber with chimney attached, in which a certain fixed
depth of bune is maintained and in which the said brine 18 continuously dashed into
a fine spray by the action of quickly revolving fanners, and (3) a mechanical
conveyor so disposed in the lower part of the evaporating chamber that it con-
tinuously withdraws the salt which is caused to deposit by the evaporation of the
brine and delivers it to a convenient receptacle where it may it necessary be
allowed to drain and whence it may be conveniently loaded into trucks or other
vessels of transport. The strong brine which leaves the salt during the process
of draining is allowed to un back again into the evaporating chamber.
In working thus improved apparatus the products of combustion from the furnace
are allowed to pass directly into the evaporating chamber where their heat is
immediately absorbed by the bine spiny thrown up by the revolving fanners, and a
very rapid and complete evaporation is the result, the aqueous vapour passing
away up the chimney along with the comparatively cool products of combustion.
When the evaporation has reached such a point that the bine is completely
saturated the salt begins to deposit in the form of granular crystals. The lower
part of the evaporating chamber is so shaped as to cause the depositing salt to
collect in a cential or side collecting trough running the length of the chamber, in
which the arrangement of mechanical conveyors 19 continously in operation
will be seen that the process of saltmaking is by this means reduced to the two
very sumple operations of firing the furnace aud maintaining the brine at a constant
level in the evaporating chamber.
It
In order to more fully utilise the heat which would otherwise be lost by
radiation from the top of the evaporating chamber and of the furnace I place paus
of wrought on cast iron over both or either of these and keep the said pans filled
with brine which evaporates slowly and deposits a coarse-grained salt of high
quality. O the brine supply for the evaporating chamber may be caused to
un through these pans and so become heated before it enters the evaporating
chamber.
In order to effect a further economy when the salt is to be loaded into wagous
or barges as is ficquently the case it is advantageous to take it either from
the diaming receptacle or direct from that mechanical conveyor which works in the
evaporating chamber by means of another mechanical conveyor to the tick of the
baige. If the salt conveyed in this manner be not sufficiently deprived of moisture
it may easily be dried to any desired extent by allowing the conveyor to pass
through a chamber in which a heated atmosphere is maintained or through which
a curient of any heated gas or gaseous mixture is caused to pass. In this way it

page_text: will be seen that it is quite possible for dry salt to be delivered into trucks or
barges without having been once touched by hand.
If for any reason it be found inconvenient to draw the salt from the evaporating
chamber by means of a mechanical conveyor the collecting tough above mentioned
should be placed along the outside of the evaporating chamber and in that case the
salt may be removed by hand labour in the usual way.
Should it happen that during the evaporation of brine or any other saline
solution the intervals between the fauner blades become filled up with salt and the
fanueis be thus caused to lose then capacity for spraying the liquor it is desi able
to place two lanner shafts (with fanners attached) parallel with one another and
so close together that the fannet blades on one shaft will work in alternately
with the fanner blades on the other shaft in order that by this means each set of
fanners may keep the adjacent set of fammers clean and fiee from the encrusting
salt
In the event of salt accumulating upon the top and sides of the evaporating
chamber to such an extent as to become a source of inconvenience the difficulty
may be over come by lining the top and sides of the chamber internally with
sheets of iron or other suitable material in such a manner that these sheets may be
easily shaken or otherwise agitated from the outside and the adheung sali be
caused to fall into the bune below whence it will of course be removed by the
mechanical conveyor.
It will be easily seen that the above described apparatus can be worked with
gaseous fuel or with waste heat from any source whatever In the latter case the
furnace may be wholly or partly dispensed with, and this modification is peculiarly
adapted for use in those chemical works where a brine supply is available and
where waste heat is being sent away to the chimney.
Dated this 18th day of October 1895
ALFRED ROLAND DAVIS.
G. F. Redfern & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.
"
1
An Improved Apparatus for the Manufacture of Salt.
I ALFRED ROLAND DAVIS of 32 Blackfriars Street Manchester Chemical
Engineer 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 has reference chiefly to the manufacture of sodium chloride or
common salt but it is also applicable to the manufacture of any other kind of salt
which can be made to separate out in a granular form from its aqueous solution
by concentration
This improved apparatus consists of three distinct parts (1) a furnace in
which coal or other fuel can be economically burned and which is so constructed, as
to melude a combustion chamber or other airaugement for secting a smokeless
flame; (2) au evaporating chamber with chimney attached, in which a certain
depth of bune is maintained, and in which the said bine is continuously dashed
into a fine spray by the action of quickly revolving fanners, and (3) a mechanical
conveyor so disposed in the lower part of the evaporating chamber that it
continuously withdraws the salt which is caused to deposit by the evaporation of
the bune and delivers it to a convenient receptacle where it may if necessary be
allowed to drain and whence it may be conveniently loaded into tracks or other
-vessels of transport The strong brine which leaves the salt during the process of
draming is allowed to run back again to the evaporating chamber.

page_text: In working this improved apparatus the products of combustion from the
furnace are allowed to pass diectly into the evaporating chamber where the heat
18 immediately absorbed by the brine spray thown up by the revolving fanners
and a very rapid and complete evaporation is the result, the aqueous vapour
passing away up the chimney along with the comparatively cool products of
combustion. When the evaporation has reached such a point that the brine is
completely saturated the salt begins to deposit in the form of granulat crystals.
The lower part of the evaporating chamber is so shaped as to cause the depositing
salt to collect in a cential or side collecting trough running the length of the
chamber in which the arrangement of mechanical conveyors is continuously in
operation. It will be seen that the process of salt-making is by this means
reduced to the two very simple operations of fiuing the furnace and maintaining
the brine at a constant level in the evaporating chamber.
In order to more fully utilise the heat which would otherwise be lost by
radiation from the top of the evapointing chamber and of the furnace I place pans
of wrought or cast on over both or either of these and keep the said pans filled
with bme which evaporates slowly and deposits a coarse-grained salt of high
quality. O the bune supply for the evaporating chamber may be caused to
run through these pans and so become heated before it enters the evaporating
chamber.
In order to effect 'a further economy where the salt is to be loaded into wagons
or barges as is frequently the case it is advantageous to take it either from the
diaming receptacle or direct from that mechanical conveyor which works in the
evaporating chamber by means of another mechanical convey or to the truck or
the barge
If the salt conveyed in this manner be not sufficiently deprived of
moisture if may easily be died to any desued extent by allowing the conveyor to
pass through a chamber in which a heated atmosphere is maintained or through
which a cuiient of any heated gas or gaseous mixture is caused to pass. In this
way it will be seen that it is quite possible for dry, salt to be delivered into trucks
or baiges without having been once touched by hand labour.
If for any reason it bc found inconvenient to withdraw the salt from the
evaporating chamber by means of a mechanical conveyor the collecting trough
above mentioned, should be placed along the outside of the evaporating chamber
and in that case the salt may be removed by hand labour in the usual way.
Should it happen that it is desired to work this apparatus with gaseous fuel or
by waste heat, the furnace and combustion chamber must be constructed
accordingly, and in the latter case may be wholly or partly dispensed with, and
it will be readily seen that this modification is peculiarly adapted for use in those
chemical works where a bime supply is available and where waste heat is being
sent away to the chimney.
The above described apparatus will be more readily understood by reference to
the sheets of drawings accompanying this specification wherein Ziepresents the
furnace wherein the fuel is burned and Y a combustion chamber wherein the gases
from Zaic exposed to a large surface of incandescent bitckwork in order to
promote complete combustion ✗ 1s the evaporating chamber to the end of
which is attached the chimney V of which only the lower portion is sbewn. Brine
is maintained at such a depth in the evaporating chamber X that the blades of the
fanneis W dip into it to a depth of about half an inch and on being caused to
rotate dash it up in the form of a spray. E represents a mechanical conveyor
disposed in the lower part of the chamber as above described so that when in
operation it continuously removes from the chamber the salt which is caused by
evaporation to deposit and collect in the trough in which the conveyor is situated.
The salt thus removed from the chamber is brought to a receptacle F from which
it 18 elevated by another mechanical conveyor G to the drainer H whence it can
be conveniently loaded into trucks while the liquor which drains from it finds its
way into the receptacle F which is connected as shewn with the evaporating
chamber.

page_text: Figures 5 and 6 shew arrangements of the apparatus in which the salt instead of
being caused to collect in a trough running along the length of the centre of the
chamber is caused to collect in a trough or troughs placed along the outside of the
chamber and it will be seen that in the event of the use of a mechanical conveyor
being found inconvenient the salt may easily be removed from such outside trough
or troughs by hand labour.
In Figures 2 and 4 are shewn arrangements which may usefully be adopted for
regulating the supply of brine to the evaporating chamber J represents a tank
divided into two portions by the partition K The top of the containing wall L is
about one eighth of an inch below the level at which it is desned to maintain the
brie in the evaporating chamber X while the top of the partition wall K is about
one eighth of an inch above this level. Into the epace between these two walls
the brine is fed by a pipe as shewn from the main feed tank M and it will be
evident that if the top of the wall L is not covered with liquor the feed of brine
must be increased, while it is equally evident that if the liquor is flowing over the
top of the wall K into the outer compartment of the tank the feed of brine must
be reduced. Any liquor which overflows the wall K into the outer compartment of
the tank J must be elevated by the pump N into the main feed tank M to be again
fed into the apparatus.
Figures and 6 shew the evaporating pans O which may be placed above the
evaporating chamber and furnace for the purpose of utilising heat that would
otherwise be wasted as alieady described.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
The combination of a source of heated smokeless products of combustion with
an evaporating chamber provided with revolving fanners or sprayers and a
mechanical conveyor for removing the salt as it is formed and deposited all
substantially as herein before set forth.
Dated the 17th day of July 1896.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.