Improvements in and in Apparatus for the Evaporation of Brine and the Manufacture of Salt therefrom.
Year: 1890

page_text: Date of Application, 9th Jan., 1890
Complete Specification Left, 10th Nov., 1890-Accepted, 9th Jan., 1891
PROVISIONAL SPECIFICATION.
Improvements in and in Apparatus for the Evaporation of Brine
and the Manufacture of Salt therefrom.
I, REGINALD COATES WILSON, of Bidston Road, Birkenhead, in the County of
Chester, Ship Owner, do hereby declare the nature of my said invention to be as
follows
This invention has chiefly for its object to produce salt from saturated saline
solutions such as are at present found and used in the salt manufacturing districts-
in a more economical and efficient manner than that in common practice at the
present time.
In the process of, and apparatus for, evaporating brine and manufacturing salt
therefrom, involving the improvements according to this invention, the evaporating
vessels are closed, that is covered in, and the steam or vapour given off from the brine
during the process of evaporation, is conveyed to a pump or compressor, mechanically
operated, by which it is compressed and its temperature raised. In this compressed
and heated condition it is passed into and through suitable pipes or conduits submerged
in or in contact with the brine to be evaporated, with the result that a transference of
heat from the fluid of the higher temperature to that of the lower temperature takes
place, and the steam is condensed, the brine to be evaporated serving as the condensing
fluid. The latent heat given out in and due to the condensation of the steam is thus
transmitted to the brine, and a weight of water of such brine, equal to the weight of
steam condensed by it, is evaporated.
The water resulting from the condensation of the steam will of course be at a
temperature corresponding with the pressure of fluid within the heating pipes or
conduits, and its sensible heat is utilized by passing it through or round tubes or
conduits in contact with the feed brine, so causing it (the sensible heat) to be
transferred to a considerable extent to such brine. In this manner a large proportion
of the total heat of the steam given off from the brine may be recovered and utilized
for the evaporation of a corresponding weight of water of the brine to that fro.
which it was originally produced.
If the compressor be worked by a steam engine, then the exhaust steam thereof
would be used in a corresponding manner to that above described to evaporate brine in
a separate or another evaporator, and the vapour from the brine so evaporated may be
used in another pan, closed or open; or according to another mode of utilizing the
exhaust steam, it may be passel, together with the compressed steam, under the first
specified evaporator, or partly in one way and partly in another.
If the compression of steam is effected by a water motor in lieu of by steam, of course
the necessary compression and heat would be obtained without the expenditure of
any fuel.
According to one and a particular kind of apparatus, the present ordinary pans are
utilized in the carrying out of this invention, and the pipes or conduits through which
compressed steam is passed are placed in the pan itself and submerged in the brine,
the pan
thus serving at once as, or constituting, the evaporating vessel and condenser.
The pan itself is covered over by non-conducting material such as woodwork-
which may be packed, stuffed, or lagged with non conducting material of any suitable
kind if necessary or desired-and provided with doors so arranged that access may be
had to the space covered over for drawing off the salt whenever required. The tubes or
conduits in the pan used for conveying the compressed steam, are so arranged that
they do not interfere materially with the process of raking or removing the salt.
working the process the pressure of steam within the space above the pan shoull be
slightly above that of the atmosphere so as to exclude air.
In

page_text: As an addition to or modification of the above described apparatus, the brine, as it is
fed to the pan, is conducted over a surface of pipes, tubes, cylinders or the like,
through or into which steam is introduced, the brine being caused to flow or run in
small or shallow streams over such surfaces on its way to the pan.
A mechanical means, such as a scraper, for keeping the surface of these tubes,
pipes, or conduits clean free from scale, may be used.
The heating tubes, pipes, or conduits, in the pan are preferably so arranged that
they can be turned up or taken out and easily and rapidly scraped and cleaned.
In some cases, to make up for loss of heat by radiation and conduction, the heating
steam may be superheated by a separate fire or furnace; or in lieu thereof a relatively
small fire may be kept burning under the pan.
In cases in which a battery of pans are worked according to this invention, one
arrangement of plan for compressing the steam may consist in providing a single
motor, say a steam engine, and a number of compressors, the motor being adapted to
drive, by suitable gearing, two or more separate compressors, one compressor being
used in connection with each pan.
It is to be understood the mode of conducting the herein described process, and the
construction and arrangement of apparatus specified or referred to, may be modified
and adapted to operate in various ways according to the varying conditions of the
application of the invention or special requirements.
Dated this 8th day of January 1800.
CHEESBROUGH & ROYSTON,
15, Water Street, Liverpool, Applicant's Agents.
COMPLETE SPECIFICATION.
Improvements in and in Apparatus for the Evaporation of Brine
and the Manufacture of Salt therefrom.
I, REGINALD COATES WILSON, of Bidston Road, Birkenhead, in the County of
Chester, Ship Owner, do hereby declare the nature of this invention and in what
manner the same is to be perforined, to be particularly described and ascertained in
and by the following statement :-
This invention has chiefly for its object to produce salt from saturated saline
solutions such as are at present found and used in the salt manufacturing districts
-in a more economical and efficient manner than that in common practice at the
present time.
In the process of, and apparatus for, evaporating brine and manufacturing salt
therefrom, involving the improvements according to this invention, the evaporating
vessels are closed, that is covered in, and the steam or vapour given off from the
brine during the process of evaporation, in conveyed to a pump or compressor,
mechanically operated, by which it is compressed and its temperature raised. In
this compressed and heated condition it is pressed into and through suitable pipes or
conduits submerged in or in contact with the brine to be evaporated, with the result
that a transference of heat from the fluid of the higher temperature to that of the
lower temperature takes place, and the steam is condensed, the brine to be evaporated
serving as the condensing fluid. The latent heat given out in and due to the con-
densation of the steam is thus transmitted to the brine, and a weight of water of
such brine at boiling point, approximately equal to the weight of steam condensed by
it, is evaporated.
The water resulting from the condensation of the steam will of course be at a
temperature corresponding with the pressure of fluid within the heating pipes or con-
duits, and its sensible heat is utilized by passing it through or round tubes or con-
duits in contact with the feed brine, so causing it (the sensible heat) to be transferred
to a considerable extent to such brine. In this manner a large proportion of the
total heat of the steam given off from the brine may be recovered and utilized for
the evaporation of a corresponding weight of water of the brine to that from which it
was originally produced.

page_text: If the compressor be worked by a steam engine, then the exhaust steam thereof
vould be used in a corresponding manner to that above described to evaporate brine
na separate or other evaporator, and the vapour from the brine so evaporated may
be used in another pan, closed or open; or according to another mode of utilizing the
exhaust steam, it may be passed, together with the compresse: steam, under the
irst specified evaporator, or partly in one way and partly in another.
If the compression of steam is effected by a water motor in lieu of by steam, of
course the necessary compression and hat would be obtained without the expenditure
of any fuel.
According to the present invention, the present ordinary pans, or equivalent pans,
are utilized in the carrying out of the invention, and the pipes or conduits through
which compressed steam is passed are placed in the pan itself and submerged in the
brine, the pan serving thus at ones as, or constituting, the evaporating vessel and
condenser.
The pan itself is covered over by non-conducting material such as wood-work-
which may be packed, stuffed, or lagged with non-conducting material of any suit-
able kind if necessary or desired and provided with doors so arranged that access
may be had to the space covered over for drawing off the salt whenever required.
The tubes or conduits in the pan used for conveying the compressed steam, are so
arranged that they do not interfere materially with the process of raking or removing
the salt. In working the process the pressure of steam within the space above the
pan should be slightly above that of the atmosphere so as to exclude air; and it may
be so worked that steam drawn off by the engine is less than that made and is always
blowing off-say into the second pan space or otherwise.
As an addition to or modification of the above described apparatus, the brine, as it
is fed to the pan, is conducted over a surface of pipes, tubes, cylinders or the like,
through or into which steam is introduced, the brine being caused to flow or run in
small or shallow streams over such surface on its way to the pan.
A mechanical means, such as a scraper, for keeping the surface of these tubes,
pipes, or conduits clean and free from scale, may be used.
The heating tubes, pipes, or conduits, in the pan are preferably so arranged that
they can be turned up or taken out and easily and rapidly scraped and cleaned.
In some cases, to make up for loss of heat by radiation and conduction, the heating
steam may be superheated by a separate fire or furnace; or in lieu thereof a
relatively small fire may be kept burning under the pan.
In cases in which a battery of pans are worked according to this invention, one
arrangement of plant for compressing the steam may consist in providing a single
motor, say a steam engine, and a number of compressors, the motor being adapted
to drive, by suitable gearing, two or more suitable compressors, one compressor
being used in connection with each pan.
In the drawings which serve to illustrate the invention
Figure is an isometrical perspective view of an arrangement of plant under the
invention wherein a steam engine is employed to compress the steam and the exhaust
steam of the engine is utilized in a pan to evaporate the brine.
Figure 2 is a plan of plant and
Figure 3 is an end view thereof, of the arrangement, wherein an engine is adapted
to drive several compressors, one compressor being used in connection with each pan.
Figure 4 shews a pan covered and arranged according to this invention,
Figure 5 is a plan of same with the covering removed, and
Figure 6 is a side elevation to a smaller scale shewing same and the doors therein.
And
Figures 7 and
invention.
show in elevation and plan a modification according to the
Referring to the drawings a designates the pan; bis the covering; c is the steam
compressing cylinder; d is the motor; e is the pipe which conveys the steam from the
pan to the steam compressor; f is the pipe through which the compressed steam
passes from the compressor to the heating tubes of the pan; h h¹² are the heating

page_text: tubes of the pan; is the pipe by which the condensed water passes from the pan
jis a feed brine heater connected to the pan by the pipe ; are pipes by which the
condensed water passes from the feed heaters j; k is a discharge pipe connecting
the pipes ; is a main brine feed pipe; are branch feed pipes from the main to
the feed heater j; m is a pipe for conveying the heated brine from the feed heater
to the pans.
The pans a shewn in the drawings are made of the same shape as those now
generally used in the manufacture of salt from brine, and may be taken as representing
the existing pans of a salt works. The covering b, which may be of wood or metal
properly lagged with a bad conductor of heat, is set into the pan as shewn, and dips
into the brine therein so that a liquid seal is provided at the point of juncture of the
pan and cover in addition to the mechanical joint which would be made.
The doors of the covering bare designated, and are provided with a counter
balance weight 22, and adapted by any known suitable kind of closing device to be
drawn up tight on to the frames in which they fit; or this action may be effected
by weights tending to press them into their frames. If the covering be of wood or
other soft material, the frames may be made of metal of any suitable kind where the
doors touch them, and the doors themselves may be similarly provided with metal
case or edging, so as to render the construction of a steam tight joint easy and simple.
Any suitable known kind of gear or mechanism may be used to operate the doors, and
a catch is provided on the roof of the covering to engage with the end of the
doors and hold them up when opened for the purpose of removing the salt or other
object.
The pipes at the bottom of the pan into which the compressed steam is passed, and
which are used for heating the brine, consist in the example shewn in Figures 4 and 5
of longitudinal tubes disposed along the edge of the pan, longitudinal tubes
disposed also along the pan about the centre thereof, and transverse pipes h² connecting
said longitudinal pipes and together. It will be seen that two of these sets of
heating pipes are shewn in the pan; this is for the object of rendering the cleaning,
and other operations connected with them, easy. The outer tubes are provided
with rings or equivalent devices--by which they are adapted to be raised by
tackle or other means suspended from the hook on the roof, it being merely
necessary for this object to connect the tackle, work it, and raise the tubes up, the
tubes h serving as the axis about which the movement takes place. The steam pipe f
passes through the pan sides, as shewn, as does also the condensed water outlet pipe i,
and the pipe h is connected to such pipes by flanges, or suitable kinds of working
steam tight joints. The pipes stand at a higher level than h, and thus the transverse
pipes 2 have a fall towards h, and the water condensed within the system thus
gravitates to the pipes, from whence it passes out of the pan by way of the
pipes i.
Air which may accumulate in the system may be withdrawn by suitable pipes con-
nected with the pipes leading out of the apparatus.
In Figures 1, 2 and 3 only single steam inlet pipes f and water outlet pipes i are
shewn; this is done for the sake of clearness, but as a matter of fact, if the heating
pipes in the pan were arranged as shewn in Figures 4 and 5, the pipe would of
course have to be in duplicate to feed the two pipes h, as would also the water outlet
pipes i.
In Figures 1 three pans are used; the first one is shewn to be acted upon directly
by the pumpe driven by the motor d, that is to say, the steam given off from the
brine in this pan is taken into the compresser e through the pipe e, and is returned to
the heating pipes h¹² through the pipe f, compressed. This system connected with
the pans presents a complete cycle within itself, the heat given off from the heating
pipes being transferred to the brine, the vapour from which is again drawn into the
pump c, compressed, and again returned. If a steam motor is employed the degree
of compression to which the steam is subjected may be, conveniently, from about
15 to 30 lbs. above that of the atmosphere.
In the second pan the exhaust steam from the motor d is led to the heating

page_text: pipes thereof by the pipe f¹, say at the same pressure and temperature as that
delivered to the heating pipes of the first pan, and acts identically in the same
way upon the brine, the steam, however from this pan being conveyed in an
uncompressed state to the third pan by a pipe el to the heating pipes thereof:
the pan in this example is an open one, but at the same time, if desired, it may
be covered in.
The pans would be, preferably, so worked, that less steam would be withdrawn
from them than is produced therein, so that at all times a proportion of steam will
be blowing off. By this mode of working the exclusion of atmospheric air is
rendered absolute, and it will be evident, that this proportion need only be a very
small one, and that the pressure under which the pan may be worked need be
merely the fraction of a pound. If desired, this steam from the first pan may be
An ordinary
conveyed into the second, or to the third with that of the second.
relief valve properly adjusted provides a convenient means for carrying off this
steam, such a valve may be placed at in Figure 1, and the steam conveyed
away by a pipe v¹. If the heat given off to the brine by the compressed steam
in the pan is not sufficient (which it may not be) to provide for that withdrawn,
plus that blown off and that which leaks away and is lost by radiation or conduction,
it may be made up by supplying other steam under the proper pressure from any
suitable source, if desired, or by keeping a small fire beneath the pan or by super-
heating the compressed steam; but in any case, this proportion of additional heat will
necessarily be insignificant relatively to the proportion recovered and reused, and to
the consequent quantity of fuel saved by the use of the methods and systems herein
set forth; that is to say, it is possible to recover from the total heat of the compressed
steam supplied to the pan, from 90 to 95 per cent., and reuse it over and over again in
evaporating fresh quantities of brine.
As a modification, in lieu of using a feed heater as herein described, the hot
condensed water may be pumped or forced into the steam generator which supplies
the motor with steam; and by this mode of carrying out the invention the already
small quantity of heat of the fuel used to raise the pressure and temperature of
the steam is further reduced. Or, in lieu of this mode, the water supplied to the
steam generator may be that discharged from the feed heaters. By this latter
mode rather better results will be obtained than by the former.
To maintain the required pressure in this system of heating pipes, a loaded valve i¹
is placed on the pipes i, and is interposed between the pan and the feed-brine heater j;
or this valve may be disposed on the fresh water discharge branches or 1, or any
suitable place or places as desired.
The feed heater j may consist of any suitable form of surface heating apparatus
generally known as feed heaters, or condensers, the cold brine being passed into it
from the branches 1, and passing through the conduits therein surrounded by the hot
water from the pan, leaves it and passes into the pan m in a heated state; whilst the
heat of the water which serves to heat the brine has been transferred thereto, and
As far as
leaves the feed heater in a comparatively cool state by the pipes k.
possible, therefore, the sensible heat of the water resulting from the condensation of
the heating steam is abstracted by these feed heaters, whilst the main portion of the
heat of the compressed steam, namely the latent heat, is transferred to the brine within
the pan as previously explained.
It will be plain, that in the case where water or other natural power is available
for the purpose of compressing the steam, the second pan and the mode of heating it,
as described with reference to Figure 1, will not be available.
With reference now to Figures 2 and 3, the system illustrated in these figures is
one in which each pan is provided with a separate compressor c, such compressors
being driven from a commion motor d. In the example illustrated in carrying out
this system, the motor d is adapted to drive an overhead shaft o, having upon it
toothed or friction bevel wheels of which gear with horizontally disposed bevel
wheels p mounted upon the upper end of vertical shafts p', the lower ends of which
are provided with disc or other cranks q driving the compressing piston of the

page_text: may
pump. Each of the pumps would be adapted to be worked separately, that is,
independently driven or stopped. This may be done by friction or other clutches,
of any known suitable kind, arranged on the shaft o; and the stroke of the pump c
may be a variable one, so that in the different pans, different quantities of heat
be supplied and at varying rates and temperatures, thus rendering it possible in a
plant arranged in this manner to produce different qualities or grades of salt. The
alteration of the stroke of the pump c may be effected by providing these pumps
with adjustable crank pins and connecting rods, so that the stroke may be longer
or shorter as required, but at the same time keeping the clearance constant.
It will be plain that other known kinds of gearing than the one shewn may be
adapted to effect the differential rate of pumping above specified.
The feed heaters are shewn provided in this system, and they work in the same
manner as those described with reference to Figure 1. At the same time in this or
any other arrangement under this invention it is not necessary that the exhaust steam
of a motor be used, as if it be a condensing engine, the whole of the steam would
be condensed and not available for the purpose of evaporating the brine; however,
such a system of working is not preferred.
In the operation of manufacturing salt by apparatus constructed as set forth with
reference to Figures 4, 5 and 6, when a sufficient quantity of salt has been deposited,
the doors are opened and it is removed (or first washed and then removed) by
scraping it to the sides of the pan (doors being provided on each side) and lifting it
out in the ordinary way. During this operation the extraction of steam may be
stopped.
According to a modified mode of collecting the salt, and at the same time
producing its deposition at a greater rate, I may employ circulating apparatus, such
as "steam-jet" apparatus of the "Korting" and "Meldrum" type, by which the
flow or circulation will be caused in the direction of the cooler end of the pan,
that is, the end at which the condensed water leaves it. These circulators, which
are designated in Figure 7, may be arranged in multiple and disposed longi-
tudinally underneath the pan, they being connected to it, at either end, by pipes
carried under the pan; or, they may be disposed within the pan as shewn in dotted
lines. By this means the flow or circulation takes place bodily as described from
end to end, and the steam used for this purpose may be taken from the boiler direct,
or from the exhaust steam from the motor, and adapted to serve as the means of
supplying to the brine the additional heat necessary as above described.
Suitable cocks or valves will be provided on any of the parts or conduits as desired
for the purpose of controlling the flow of the fluids.
Having now particularly described and ascertained the nature of this invention and
in what manner the same is to be performed, it is to be stated in conclusion that the
invention is not confined to the constructions, arrangements, and combinations of
parts herein before more particularly described with reference to the drawings, as the
different arrangements shewn in the different figures may be combined in various
ways to suit special applications of the invention and the different conditions under
which it may be used; also the form and general construction of the pans, and their
coverings, and arrangement of heating pipes, may be carried out in different modified
manners to the ones shewn ; but what is claimed in respect of the herein described
invention is :-
1. The improvement in the manufacture or production of salt from brine herein
described, consisting in evaporating the brine and depositing salt within the pan
or pans by steam which has been given off from brine therein, and compressed,
and condensed within tubes disposed within said pan or pans; substantially as
described.
2. In the manufacture of salt from salt from brine, effecting the evaporation of
the brine in one or more pans in the manner referred to in Claim 1, and in one or
more other pans by the exhaust steam from the motor used to compress the steam;
substantially as described.

page_text: 3. The production or manufacture of salt from brine substantially in the manner
set forth with reference to Figure 1, and Figures 2 and 3, respectively.
4. In the manufacture of salt from brine in closed vessels, the herein described
improvement of carrying on the process, consisting in withdrawing a portion only
of the steam produced for the purpose of compression, the remaining portion being
blown off or passed away, and the vessel being worked under a pressure in excess of
that of the atmosphere; substantially as described.
5. In systems of producing salt from brine after the manner referred to in the
preceding claim, supplying heat to the brine to be evaporated in addition to that
supplied by the compressed steam; substantially as and for the purposes set forth.
6. Effecting the circulation and rapid evaporation of brine and improved
deposition of salt substantially in the manner herein set forth; that is to say, by the
employment of steam-jet circulators arranged and adapted in combination with the
pan and operating substantially as set forth.
7. The arrangement and construction of apparatus for the manufacture of salt from
brine substantially as set forth with reference to Figures 3, 4 and 5 of the drawings,
for the purposes set forth.
8. The combination of parts of the plant set forth with reference to Figure 1,
and Figures 2 and 3, respectively, for the manufacture or production of salt from
brine.
9. In the manufacture of salt from brine a pan adapted to hold the brine and
fitted with heating tubes and constituting the evaporating vessel and condenser
combined, the vapour given off in said pan being that employed within said tubes as
the heating fluid and condensed therein, substantially as described.
Dated the 8th day of November 1890
CHEESBROUGH & ROYSTON,
15, Water Street, Liverpool, Applicant's Patent Agents.