Improvements in Machinery or Apparatus for Obtaining Salt from Brine.
Year: 1894

page_text: Date of Application, 10th May, 1894
Complete Specification Left, 11th Mar., 1895-Accepted, 13th Apr., 1895
PROVISIONAL SPECIFICATION.
Improvements in Machinery or Apparatus for Obtaining Salt
from Brine.
I, RALPH HODGSON, of 47, Malvern Street, Sparkbrook, Birmingham,
Warwickshire, Mechanic, do hereby declare the nature of this invention to be as
follows:-
This invention consists of the herein described improvements in machinery or
apparatus for obtaining salt from brine. Heretofore it has been customary to heat
the brine pans by fires underneath and as the salt accumulates in the bottom of the
pans the latter very often become red hot in parts and are soon burnt through or
seriously damaged and then have to be repaired. Moreover a large percentage of
the heat generated for the evaporation of the brine is lost in burning away the pans
and in heating the salt contained therein and the walls of the furnaces.
By my invention, instead of heating the pans directly by fires underneath, I heat
the brine in the pans by steam in pipes of peculiar construction which are arranged
in the pan as herein described and in combination with these pipes I employ a
continuously moving scraper or scrapers which prevent the salt accumulating on
the pipes and collect the salt as it is formed aud deliver it out of the pau ready for
drying. I am thus enabled to very considerably economise fuel and as I work at
an uniform temperature all over the pans the latter cannot become overheated as
at present and therefore the cost of maintaining the pans is very considerably
reduced. Moreover when my invention is used the said evaporating pans may be
made of wood instead of being made of iron or other metal as at present thus
considerably reducing the first cost of the same.
My invention is carried out as follows:-I provide an evaporating pan of any
convenient shape but by preference circular in plan although the said pan may be
oval, square, or of other form. This pan can either be made of iron or steel as at
present or of wood or otherwise suitably formed. At the bottom of the pan I
provide an arrangement of steam pipes made in sections bolted together aud
arranged in rings round the centre of the pan, or the said steam pipes may be made
to radiate from the centre of the pan towards the periphery, or be arranged in a
zig-zag manner, or in lines to and fro, or otherwise arranged so as to partly cover
the bottom of the pan and afford sufficient heating surface to raise the brine to the
proper temperature. The top sides of these pipes are made flat and the flanges and
joints are so arranged as not to stand up above the level of the top of the pipes
nor obstruct the scraper or scrapers moving over the pipes as hereinafter described.
These steam pipes are connected at one or more points to a steam supply pipe or
steam supply pipes from one or more steam boilers and in the lower parts of the
pipes there are outlets leading to steam traps for the escape of the hot water formed
by the condensed steam, this hot water running through a heater or heaters by
which the brine is warmed before it enters the evaporating pans. The said scraper
or scrapers above referred to is or are arranged to move in a circular direction or
in straight lines or to and fro or otherwise over the top side of the steam pipes
so as to scrape the salt off the top of the steam pipes as it is formed and collect it
to one part of the pan where there is an incline which rises up out of the brine so
that as the scraper moves over this incline it brings the salt with it out of the brine
up to the top of the incline and then as it moves along the scraper has a sudden

page_text: drop through a short space and the salt which it has accumulated falls through an
outlet in the bottom of the pan into the moulds. The sides of this outlet rise up
above the level of the brine so as to prevent the brine running out. As the scraper
continues to move it passes over the said outlet and down again into the brine
ready to collect some more salt. The space between the steam pipes become filled
with salt and thus with the flat tops of the pipes forms a level bottom for the
scraper or scrapers to work upon. When the evaporating pans are made of a long
trough shape the said scraper or scrapers work along the same from end to end and
deliver the salt up an incline at one or both ends of the pan. In this case the
scrapers may conveniently be connected to a travelling chain or chains or to a band
or bands above the evaporating pan and either move along the pan to and fro from
end to end or after moving along the pan from one end to the other the scrapers
then return over rollers to the other end of the pan where they again dip into the
brine and move forward as before. It will be seen that by my invention the action
of the salt pan is continuous and the salt is removed by the scrapers as quickly as
it is formed.
When the salt pan is made circular or of other form with the revolving scrapers
as above described the steam pipes are by preference arranged in one two or more
sections, that is an inner section and two or more outer sections each having a
separate scraper or scrapers which scrapers are arranged slightly at an angle so
that the salt as it is formed and collected by the scrapers moves out from the inner
scraper towards the outer scraper or scrapers which latter is or are made to move
up the incline and deliver the salt as above described. The scrapers when arranged
to revolve can readily be driven by a central shaft passing up through a tubular
part at the centre of the pan this shaft being provided with one or more radiating
arms above the pan to the extremities of which the scraper or scrapers is or are
connected; the said vertical shaft being arranged to rotate by bevel gearing or by
other mechanism underneath the pan. Or instead of the driving mechanism being
arranged underneath the pan the said mechanism may be arranged above the
same.
Instead of employing open pans as above described I may employ airtight
vacuum pans with the scrapers arranged to revolve inside the same.
In this case
the salt which is delivered by the scrapers falls through the opening in the pan
into a closed chamber from which it is removed after a valve in the said outlet has
been closed so as to shut out the pressure of the atmosphere from the vacuum pan.
When the salt has been removed from the chamber the said chamber is then closed
again and the valve opened for the salt to be delivered as before. The vapour as
formed in the vacuum pan is removed by an airpump or other well known means
as used in connection with other vacuum pans.
Dated this 9th day of May 1894.
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.
MILELE CECIFICATION,
Improvements in Machinery or Apparatus for Obtaining Salt
from Brine.
I, RALPH HODGSON, of 47, Malvern Street, Sparkbrook, Birmingham,
Warwickshire, Mechanic, 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 the herein-described improvements in machinery
or apparatus for obtaining salt from brine. Heretofore it has been customary to

page_text: heat the brine pans by fires underneath and as the salt accumulates in the bottom
of the pans the latter very often become red hot in parts and are soon burnt
through or seriously damaged and then have to be repaired. Moreover a large
percentage of the heat generated for the evaporation of the brine is lost in burning
away the pans and in heating the salt contained therein and the walls of the
furnaces.
By my invention, instead of heating the pans directly by fires underneath, I heat
the brine in the pans by steam in pipes of peculiar construction which are arranged
in the pan as herein described and in combination with these pipes I employ a
continuously moving scraper or scrapers which prevent the salt accumulating on
the pipes and collect the salt as it is formed and deliver it out of the pan ready for
drying. I am thus enabled to very considerably economise fuel and as I work at
an uniform temperature all over the pans the latter cannot become overheated as at
present and therefore the cost of maintaining the pans is very considerably
reduced. Moreover when my invention is used the said evaporating pans may be
made of wood instead of being made of iron or other metal as at present thus
considerably reducing the first cost of the same.
I will describe my invention by referring to the accompanying drawings on
which Fig. 1 is a plan of a brine evaporating pan with my invention applied;
Fig. 2 is a sectional elevation of the same on line X X of Fig. 1 and Fig. 3 is a
sectional elevation of the same on line Y Y of Fig. 1.
The same letters of reference indicate the same parts in all the figures.
My invention is carried out as follows:-I provide a circular evaporating
pan A of convenient depth and made either of iron or steel as at present or of wood
or otherwise formed. Resting on the bottom of the pan I provide an arrangement
of steam pipes such for instance as shewn upon my drawings made in sections bolted
together and arranged in rings round the centre of the pan so as to partly cover
the bottom of the pan and afford sufficient heating surface to raise the brine to the
proper temperature. The said steam pipes may be arranged in various ways but I
prefer the arrangement shewn upon my drawings where it will be seen that the
steam pipes are arranged in two series one of which B1 B2 receives live steam from
a steam boiler by the pipe c the steam passing underneath the pan and up through
the bottom into the inlet b' Fig. 1 and then circulating along and towards the
centre and round the inner circle of pipes marked B' in the direction indicated by
the arrows and then to the second larger circle of pipes marked B and round the
same to the outlet marked 62 from which the steam and condensation water pass
down through the bottom of the pan and away by the outlet pipe d to a steam
trap or through pipes in any well known water heater for heating the brine before
it is delivered to the pan A. The second series of steam pipes consists of an inner
circle E receiving live steam by the pipe f underneath the pan entering at the
inlet e and circulating round the inner circle E' in the direction indicated by
the arrows and then back along the outer circle E to the outlet e³ and away by the
pipe to the steam trap or brine heater above referred to. The top sides of
these steam circulating pipes B' B' E' E' are made flat and the flanges and joints
are so arranged as not to stand up above the level of the top of the pipes nor
obstruct the scrapers H I moving over the pipes as hereinafter described. The
spaces between the said steam pipes at the bottom of the pan become filled with
salt and thus with the flat tops of the pipes form a level bottom for the scraper or
scrapers to work upon. The scrapers H I are arranged to revolve round the
centre of the pan which can readily be done by connecting them as shewn by the
rods to the outer ends of two radiating arms marked respectively J' J' fixed
on to the vertical shaft K above the level of the brine this shaft passing up through
a bearing in the centre of the pan A and also turning in a footstep M fixed on
the foundations the necessary rotary motion of the vertical shaft K being obtained
by the bevel wheel and pinion n² n² from the horizontal shaft o underneath the pan
receiving rotary motion from any convenient source. The scraper H moved by the
longer arm J' travels round the outer circle that is over the series E¹ E of the

page_text: steam pipes and the other scraper I moved by the shorter arm J' travels round in
a smaller circle over the smaller series of pipes B₁ B' the central shaft K with the
scrapers revolving in the direction indicated by the arrow outside the left hand
side of the pan in Fig. 1. P is an outlet for the salt through the bottom of the
pan the sides p' p² på of the outlet rising up above the level of the brine so as to
prevent the brine running out through the outlet. The level of the brine is
indicated by the dotted line q in Figs. 2 and 3. R is an incline made the full width
of the path of the scraper H and rising up from the bottom of the pan to some little
distance above the brine level as shewn in Fig. 3; then there is a sudden drop on
to the level side ledges s' which are just above the level of the brine and extend
the width of the outlet P and terminate on another incline T on the other side of
the outlet P and leading down to the bottom of the pan.
When the brine is being evaporated by the steam circulating through the
pipes B B E E² and the scrapers H 1 are revolving as aforesaid the scrapers
scrape the salt off the top of the steam pipes as it is formed and collect it to the
part of the tank near the incline R so that as the scraper H moves over this incline
it brings the salt with it out of the brine up to the top of the incline R and then as
the scraper moves along the scraper has a sudden drop at the termination of this
incline R through a short space on to the level side ledges so that the salt
which has accumulated falls off the scraper through the outlet P into the moulds.
As the scraper H continues to move it passes along the ledges s¹s over the outlet P
and down the incline T into the brine again so as to collect some more salt and
deliver it through the outlet P when it has made another revolution and again
arrived at the outlet P. As the salt is formed and collected by the scrapers H I
as aforesaid the salt moves out from the inner scraper I towards the outer
scraper H so as to be delivered through the outlet P as stated above. It
will be seen that by my invention the action of the salt pan is continuous and
the salt is removed by the scrapers as quickly as it is formed.
The pan A is carried by a firm foundation such as the brick pillars U say eight
in number arranged at intervals round the bottom of the pan.
The accompanying drawings illustrate what I consider to be the best method of
carrying my invention into practice but it is to be understood that my said
invention is not limited to the precise details and arrangement shewn as it
will be evident that without departing from the nature of my invention a
single scraper or more than two scrapers might be employed; also that the
steam pipes might be arranged in different ways on the bottom of the pan and
made of a different shape to that shewn.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what I
claim is :-
:-
1. In a brine evaporating pan for the manufacture of salt, the employment of
steam circulating pipes arranged along the bottom of the same so as to evaporate
the brine, in combination with a scraper or scrapers adapted to revolve over said
pipes and collect the salt as it is formed in the brine, and periodically rise up an
incline out of the brine and deliver the salt out of the pan all substantially as
hereinbefore set forth.
2. The combination of a circular brine evaporating pan, flat topped steam
circulating pipes arranged in a circular direction along the bottom of the pan
so as to evaporate the brine, one or more scrapers connected to an arm or arms
radiating from a vertical spindle at the centre of the pan, means for turning said
spindle to revolve said scraper or scrapers, a salt delivery outlet in the bottom of
said pan having an incline on one side up which the scraper travels or scrapers
travel out of the brine, a drop to the outlet at the termination of this incline, and
another incline down which the scraper travels or scrapers travel into the brine all
substantially as and for the purposes herein before described with reference to the
accompanying drawings.

page_text: 3. The combination with a brine evaporating pan of the means for evaporating
the brine and for automatically collecting and delivering the salt out of the pan as
it is formed therein substantially as hereinbefore set forth.
Dated this 9th day of March 1895.
RALPH HODGSON.