Improvements in or connected with the Manufacture of Salt.
Year: 1894

page_text: Date of Application, 17th Feb., 1894
Complete Specification Left, 17th Nov., 1894-Accepted, 29th Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in or connected with the Manufacture of Salt.
I, REGINALD COATES WILSON, of 51 Bidston Road, Birkenhead, in the County
of Chester, Ship Owner, do hereby declare the nature of this invention to be as
follows:-
This invention has reference to the manufacture of salt from brine by evaporation,
and its object and effect, amongst other things, is the provision of improvements
connected with the manufacture, and in the construction and arrangement of plant,
whereby the fuel and heat used in the evaporation of the brine shall be employed
to the best advantage, that is, so as to obviate as far as possible, all losses, from
the combustion of the fuel to the transference of heat produced, to the liquid brine,
and the discharge of the gases of combustion, which losses more or less have
existed in all practical processes hitherto proposed or practiced where they have
been attempted to be carried out in connection with such apparatus as will permit
of the process of withdrawing salt in a simple manner, and with simple plant and
apparatus and a further object and effect of my invention is so to carry out the
manufacture of salt as to render practicable and profitable the use of cheaper fuels
(usually smaller) than those necessarily employed at present under the present
system of evaporating the brine.
According to this invention, the evaporation of brine is effected by steam which
is introduced into a system of pipes immersed in the brine in ordinary shallow salt
pans, the steam being generated in suitable generators by coal (or analogous fuel)
of cheap or small kind and burned, preferably, by artificial draught; the pans
being set upon a suitable foundation, with a suitable bad conductor of heat under
them, and, preferably, also at the sides. The steam as generated is conducted
direct to the system of pipes in the pans, and the condensed water, resulting from
the transference of heat to the brine, is conducted directly therefrom back into the
steam generator, thereby preventing loss of heat, and supplying the steam generator
with feed water of the same temperature as that within it and the steam in the
heating pipes, or approximately so. The simplest means of effecting this action
and effect is to dispose the salt pan and pipes above the level of water in the
generator, and giving the pipes drainage inclination, whereby the water can flow
back by gravity, the boilers being set in close proximity to the pans; loss of heat
by radiation or otherwise should then be very small.
As regards the part of this invention having reference to the utilization of small
and cheap fuels (cheaper and smaller than practical and profitable in the present
system) to the best advantage, for rendering this possible I use steam generators
and burn the fuel in them and work the fires with forced draught, as by steam jet
blowers such as those of the "Meldrum" type, and utilize the steam as above
described. To utilize fuels of the character above specified to the best advantage,
it must be effected by forced draught as above stated, but forced draught is not a
practicable and useful thing in connection with salt pans fired underneath as at
present, and I therefore, to obviate this, burn the fuel in steam generators as
described, whereby the most advantageous use of the fuel can be made, and
employ the steam so generated without any material loss of heat.
In one arrangement of pans and steam generators, each pan is combined with a

page_text: separate steam generator, and free connection between the steam space and the
pipes and the pipes and the water space of the generator, is provided, so that an
open system exists.
In another arrangement, two or more steam generators are arranged in conjunction
with a battery of pans, the steam generators being disposed in such contiguity
therewith, that the distance of flow for the steam to the pan pipes, and from such
pans to the boiler for the return water, is small.
As regards the generation of steam and the utilization of the full heat value of
the fuel, in one arrangement the heat of the fuel after leaving the steam generator
is carried to a brine feed heater placed in or over the outlet flue, and in one case
may consist of a simple vessel, such as a pan, with flues carried under it, and
through which the brine is passed, it being guided therein so as to travel a long
distance, and the pan is covered with a suitable cover to prevent evaporation, and
lagged or lined to prevent loss of heat.
In one arrangement of pan and pipes, said pipes run parallel with the direction
of the width of the pan, and in pans of considerable width, they are connected to a
central longitudinal supply pipe or main, from which they spring on either side,
whilst at their outer end no longitudinal or other pipes or parts exist. A free:
course is thereby provided for the drawing of the salt without any obstruction, the
water due to the condensation of steam in said pipes flowing back along same to
the central main or conduit; or to a separate pipe, and finally taken off and back
to the boiler as above described.
In some cases the pipes are arranged one above another with a bend at their
outer end; whilst in other cases a single pipe (or duplex pipe) with blank ends
may be provided and adapted to be connected to the main pipes.
All the conveying pipes and parts will be provided with suitable valves and
cocks where they may be needful, and covered in suitable non-conducting substance,
or carried in troughs and covered. In some cases the steam pipes conveying the
steam to the pan may be arranged in or pass through flues, through which the
products of combustion of the fuel passes, and so the steam becomes dried or
partially superheated.
Dated this 16th day of February 1894.
CHEESBROUGH & ROYSTON, Fels. Chart. Inst. P.A.,
15, Water Street, Liverpool, Applicant's Patent Agents.
improvements in or connected with the Manufacture of Sait.
I, REGINALD COATES WILSON, of 51 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 performed, to be particularly described and
ascertained in and by the following statement :-
This invention has reference to the manufacture of salt from brine by
evaporation; and its object and effect, amongst other things, is the provision of
improvements connected with the manufacture, and in the construction and
arrangement of plant, whereby the fuel and heat used in the evaporation of the
brine shall be employed to the best advantage, that is, so as to obviate as far as
possible, all losses, from the combustion of the fuel, to the transference of the heat
produced, to the liquid brine, and the discharge of the gases of combustion, which
losses more or less have existed in all practical processes hitherto proposed or
practiced where they have been attempted to be carried out in connection with
such apparatus as will permit of the process of withdrawing salt in a simple
manner, and with simple plant and apparatus; and a further object and effect of

page_text: my invention is so to carry out the manufacture of salt as to render practicable and
profitable the use of cheaper fuels (usually smaller) than those necessarily employed
at present under the present system of evaporating the brine.
According to this invention, the evaporation of brine is effected by steam, which
is introduced into a system of pipes immersed in the brine in ordinary shallow salt
pans, the steam being generated in suitable generators by coal (or analogous fuel)
of cheap or small kind, and burned, preferably, by artificial draught, the pans
being set upon a suitable foundation, with a suitable bad conductor of heat under
them, and, preferably, also at the sides. The steam as generated is conducted direct
to the system of pipes in the pans, and the condensed water, resulting from the
transference of heat to the brine, is conducted directly therefrom back into the
steam generator, thereby preventing loss of heat, and supplying the steam generator
with feed water of the same temperature as that within it and the steam in the
heating pipes, or approximately so. The simplest means of effecting this action
and effect is to dispose the salt pan and pipes above the level of water in the
generator, and giving the pipes drainage inclination, whereby the water can flow
back by gravity, the boiler being set in close proximity to the pans; loss of heat
by radiation or otherwise should then be very small.
As regards the part of this invention having reference to the utilization of small
and cheap fuels (cheaper and smaller than practical and profitable in the present
system) to the best advantage, for rendering this possible, I use steam generators
and burn the fuel in them and work the fires with forced draught, as by steam jet
blowers, such as those of the "Meldrum" type, and utilize the steam as above
described. To utilize fuels of the character above specified to the best advantage,
it must be effected by forced draught as above stated; but forced draught is not a
practicable and useful thing in connection with salt pans fired underneath as at
present, and I therefore, to obviate this, burn the fuel in steam generators as
described, whereby the most advantageous use of the fuel can be made, and employ
the steam so generated without any material loss of heat.
In one arrangement of pans and steam generators, each pan is combined with a
separate steam generator, and free connection between the steam space and the
pipes, and the pipes and the water space of the generator, is provided, so that an
open system exists.
In another arrangement, two or more steam generators are arranged in conjunction
with a battery of pans, the steam generators being disposed in such contiguity
therewith, that the distance of flow for the steam to the pan pipes, and from such
pans to the boiler for the return water, is small.
As regards the generation of steam and the utilization of the full heat value of
the fuel, in one arrangement the heat of the fuel after leaving the steam generator
is carried to a brine feed heater placed in or over the outlet flue, and in one case
may consist of a simple vessel, such as a pan, with flues carried under it, and
through which the brine is passed, it being guided therein so as to travel a long
distance; and the pan is covered with a suitable cover to prevent evaporation, and
lagged or lined to prevent loss of heat.
In one arrangement of pan and pipes, said pipes run parallel with the direction
of the width of the pan, and in pans of considerable width, they are connected to a
central longitudinal supply pipe or main, from which they spring on either side,
whilst at their outer end no longitudinal or other pipes or parts exist, a free course
is thereby provided for the drawing of the salt without any obstruction, the water
due to the condensation of steam in said pipes flowing back along same to the
central main or conduit; or to a separate pipe, and finally taken off and back to
the boiler as above described.
In some cases the pipes are arranged one above another with a bend at their
outer end; whilst in other cases a single pipe (or duplex pipe) with blank ends
may be provided and adapted to be connected to the main pipes.
All the conveying pipes and parts will be provided with suitable valves and
cocks where they may be needful, and covered in suitable non-conducting

page_text: substance, or carried in troughs and covered. In some cases the steam pipes
conveying the steam to the pan may be arranged in or pass through flues, through
which the products of combustion of the fuel passes, and so the steam becomes
dried or partially superheated.
Drawings illustrating this invention are annexed hereto and form part of this
Specification.
Figure 1 is an elevation, Figure 2 is a plan, and Figure 3 a cross section,
shewing one arrangement and construction under this invention, wherein a pan, or
each pan of a series, is provided with and worked by its own steam generator.
Figure 4 is a plan and Figure 5 is a longitudinal section shewing an arrangement
wherein a battery of pans are arranged in connection with a plurality of steam
generators.
In the different views the same letters and figures of reference are used to
denote the same or like parts wherever they occur.
Referring in the first instance to Figures 1 to 3, a is the pan in which the
brine is evaporated, it being set upon a foundation b, and resting upon a bad
conductor of heat, as ashes, bricks, or the like. c is the steam generator set at a
lower level than the pan a. d is the main steam distribution pipe, it being arranged
along the centre of the pan; and d' are branch heating pipes connected with same,
and extending right and left therefrom. e is a pipe leading from the steam
generator c to the pipe d and upon which a stop cock is provided. f is the pipe by
which the condensed water from the pipe d flows by gravity back to the boiler c.
g is a flue passing under the pan a by which the gases from the steam generator c
are carried away, and his a pipe passing through same, through which the brine
fed to the pan a is conveyed, and by which it becomes heated, prior to being
delivered into the pan.
As regards the arrangement of pan and the heating pipes therein, this is shewn
in Figure 3. It consists of the main distributing steam pipe d arranged along the
centre of the pan, and having a slight fall towards the steam generator, and
tubes.d' with stopped ends, connected to and communicating with d, and set at an
inclination so as to give a fall towards same. These pipes are not carried up to
the side of each pan, but are stopped within say two or three feet of the side of the
pan, so providing a space marked by the distance x in Figure 3.
By this
arrangement as shewn of the pipes d' and d, a clear space from the centre of the
pan between such adjacent pair of pipes is provided on each side of the pan,
within which the usual rake for drawing salt to the side can be introduced and
worked, and by the absence of pipes or other impedimenta along the sides of the
pan, the salt so drawn can be removed by the usual means without hindrance from
the side spaces at the sides of the pan. Thus, by this system and arrangement
of pipes, practically the same facilities exist under this invention for the collection
and withdrawal of salt, as exists under the usual method or system of making salt
now adopted.
As
The preferred and complete operation and process as a whole is :- Steam is
generated in the steam generator from fuel of a small or poor quality by forced
draught supplied preferably by steam jet blowers, as in the "Meldrum" furnace ;
and the steam space of the generator is put in free communication with the heating
pipes d d of the pan through the pipe e, so that the steam space of the steam
generator and the space within the heating pipes d and d' are practically one.
the heat of this steam is transmitted to the brine surrounding the pipes, it is
condensed, and, suitable fall being given to the pipes, it is led back by them into
the main pipe d, and flows by gravity by the pipe back into the steam generator.
Thus a free circulation, i.e. outward flow of steam and return flow as water, is
maintained by the steam generator, all the pipes being practically under the same
pressure; while the pipes e and foutside the pan would be properly covered with
a bad conductor of heat. Then, also, the heat in the gases of combustion after
leaving the steam generator, is utilized in heating up the brine used, on its way to
the pan, viz., in passing through the pipe h, whereby the pan is fed with hot brine.

page_text: By these means and this mode of operation, the obviation of practically all loss.
of heat is effected, and economy of cost of production of salt, both as regards the
price and the quantity of fuel used is effected.
As a modification under this invention, in some cases, as where the production
of salt is being conducted under modified conditions, or the circumstances of the
application renders it necessary; or in cases where it may be deemed desirable or
advantageous, the direct return of hot condensed water to the steam generator or
generators specified in the method or process of salt making herein described, may
be assisted or effected by artificial means as an injector or pump.
The steam generator will be made of such a size, and have such an amount of
heating surface, as will enable the greatest amount of heat to be absorbed or
transferred to the water as possible.
Whatever slight loss of steam or water from the apparatus may take place, it.
may be supplied to the steam generators by an injector or pump.
According to the quality or grade of salt required, so will be the pressure of
steam raised and used; that is to say, for the finer grades of salt, say up to
ordinary "butter-salt "higher pressures will be used, viz., such a pressure as will.
keep the brine in the pan up to the temperature required to produce that quality
or grain; whilst for lower or coarser grains, lower pressures will be used. Thus,.
whatever grade or quality of salt is to be made, upon it being found what pressure
and temperature will heat the brine in the pan to the degree necessary to produce-
such grade, the continuous production of that grade can be effected, its production
being independent of any circumstances, practically, other than this; and therefore
its production can be made with the greatest facility and certainty, while the salt.
so produced will be practically of uniform grade and quality at all points of
the pan.
As a modification of the arrangement and system of pipes specified with,
reference to Figure 3, in lieu of having single pipes d' as described, double
pipes may be used, as indicated in dotted lines and marked d²; in which case,
a second upper central pipe d³ will be used through which the steam would
pass into the pan and be distributed; whilst the condensed water would travel
by the pipes d'into the lower main d; from which it would be taken by
the pipe back to the steam generator.
In some cases where desirable and convenient, a second pan i may be used in
connection with the pan a, such pan being set over a chamber or flues into which
the gases from the flue g are introduced, and whereby low qualities of salt, such as.
fishery-salt," may be made by the heat of the waste gases from the boiler.
86
In the modification shewn in Figures 4 and 5, a battery of six pans are shewn
arranged to be heated by three steam generators; namely, the central steam
generator is shewn to supply the two pans on the left with steam, while each of
the two outside steam generators supplies steam to the two remaining pans of the
sets of three on either side, adjacent to them, the condensed water from the pans
connected with their respective boilers, being fed back to them by separate return
condensed water pipes f. The steam generators are set in a bed together, and the
gases leaving them are conveyed under a separate pan k, through flues or a
chamber thereunder; and through which pan the feed brine to the pans a is
passed. This pan is covered over so as to prevent evaporation, and is provided
with partial diaphragms k' to give the brine a zig-zag and guided passage through
the pan, said pan being on an elevated position above the pans a to give the
required fall for the brine to them; while the steam generators c are set below
the level of the pans a and so give the required fall for the return of the condensed
water thereto.
In the modification shewn in Figure 6, the same direct combination of steam
generator and pan as set forth with reference to Figures 1 and 2 is employed ;
but in this case the steam generator c in lieu of being placed longitudinally across
the end of the pan, is arranged, for the greater part, under the pan, it being in
other respects substantially the same. By this arrangement, economy in the space

page_text: occupied by the plant is secured, and the prevention of radiation of heat from the
steam generator facilitated.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
:-
1. A plant or apparatus for manufacturing salt from brine by steam, comprising
a pan of the kind specified, with heating-pipes therein, immersed in the brine, and
a steam generator, the steam space whereof is in direct and open communication
and combination with the pipes in the pan, the said steam generator being worked,
and the said parts being arranged and combined substantially as herein described, and
as shewn in the drawings hereto annexed.
2. In the manufacture of salt from brine by steam heat, a pan having heating
pipes immersed in the brine therein, and a steam generator in connection with, and
arranged at a lower level than, said pan, and the steam space whereof is in direct
connection with said pan-pipes, the condensed water being conveyed back from
said pan-pipes to the steam generator by a pipe from same; for the purposes
described.
3. In apparatus for manufacturing salt by steam heat, the employment in a
pan of the kind specified, of heating pipes arranged substantially as described,
by which the raking of the salt and the withdrawal of same is effected without
hindrance.
4. The salt making plant or apparatus having its parts arranged, combined,
and operating, as set forth with reference to and shewn in Figures 1 and 2,
and also Figure 6, of the drawings.
5. The salt making apparatus having its parts arranged, combined, and
operating, as set forth with reference to and shewn in Figures 4 and 5 of the
drawings.
■ 16th day of November 1894.
CHEESBROUGH & ROYSTON, Fels. Chart. Inst. P.A.,
15, Water Street, Liverpool, Applicant's Patent Agents.