Improvements in Apparatus for the Manufacture of Salt.
Year: 1889

page_text: Date of Application, 9th Apr., 1889-Accepted, 7th Sept,
1889
COMPLETE SPECIFICATION.
[Communicated from abroad by JOHN LOUIS ALBERGER, of Franklin Street and
Terrace, Buffalo, New York, Mechanical Engineer, HORACE WILLIAMS, of
Tifft House, Buffalo, New York, Gentleman, and LOUIS ROSS ALBERGER, of
88, Liberty Street, New York, Mechanical Engineer, all in the United States
of America.]
Improvements in Apparatus for the Manufacture of Salt.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings in the County of Middlesex, 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 relates to the manufacture of salt, also to the machinery or
apparatus used for making fine natural grain salt without grinding and to that used
for abstracting the salt from the evaporating vessel, the result being the production
of a practically pure salt, all of which is done in a new and useful manner and at a
reduced cost.
The improved machinery or apparatus is shown in the accompanying drawings,
in which
Figure 1 sheet 1 is a general side elevation partly in section, and
Figures 2, 3, 4, 5 and 6 sheet 2 are enlarged details of parts of the apparatus.
The method of heating the brine in tubular heaters under hydraulic pressure,
evaporating it partly in open and partly in closed evaporators, utilizing the steam
from the brine to aid the work, and operating by a continuous current of circulating
brine through the apparatus, is similar to that described in United States Patent
No. 351,082 October 19th 1886.
The operation of this apparatus or part of it may be so modified as to dispense
with the through circulation and which will be hereafter described. In Figure 1.
A A, B and C are tubular heaters, one of which is also shown partly in section in
Figure 2, A and A¹ are heated with steam from a boiler by pipe S with valves V
and V to supply and cut off the steam. Heaters B and C are heated by steam,
from the evaporators D and E through the pipes S₁ and S³. These evaporators
receive the highly heated brine coming from the gravel boxes F and G and deliver
it through the passage P10 into the circular open grainer H which may be of any
size. A practical one would be 41 feet diameter, made of iron, or other suitable
material. This size will be ample to produce from 125 to 150 barrels of salt
per 24 hours, varying according to the quality and dryness required. Attached to
the bottom of the grainer and opening into it, is a mixer I into which the salt is
swept from the bottom of the grainer by the revolution of the shaft K, the arms R
and the scraper L. The valve V draws out the mixed brine and salt into the
centrifugal apparatus J where the salt is retained, the brine drawn out and carried
by pipe P into tank Z.
Through the centre of the shaft K is a small shaft T which at its top above the
grainer carries four arms, equidistant from each other and reaching over the surface
of the grainer from the centre to the outside of it. These arms sweep over the surface
of the grainer when rotated, and agitate completely every part of the surface of the
brine in it by means of pendants of chain or metal and small agitators, marked W
which I call flippers, and which are shown in enlarged detail in Figure 5 sheet 2.
The shafts K and T are driven in any convenient manner, and at a suitable rate of
speed. The arms carried by K are rotated once in six minutes and those carried
by T six times a minute. The object is to avoid stirring up the entire contents of
the grainer by the rakes; so they revolve slowly near the bottom and are entirely
submerged. For the same reason, the flippers touch only the surface of the hot

page_text: brine at the top of the grainer, the brine at the bottom being colder, hence a better
heat is obtained on the surface where the salt is made and evaporation takes place,
than when the whole contents is stirred as is usually done in self-raking apparatus
for grainers. M is an elevator, of ordinary kind, which takes the salt after it leaves
the centrifugal and deposits it in the dryer, which may be of any ordinary construction.
The elevator O carries the dry salt from the drier to the bolts X X in which it is
separated into the necessary sizes. Y is an elevator to carry the gravel from a
receiving hopper F below the gravel boxes to a delivery one F above them. P10 is
a pipe supplying brine which comes through the exhaust heater and in which it is
heated by the exhaust steam from the pumps and engines before entering the
apparatus. A is a pump which takes brine from tank Z and elevates it through a
pipe into the suction pipe leading from the grainer H through the heater C to the
pump A as shown in Figure 1. B and B are hot wells receiving hot water
condensed from the steam supplied from the boiler or generator in heaters A and A¹
and the vapour from the brine in evaporator D condensed in heater. B.; all of which is
utilized for feed water to the boiler supplying steam to the apparatus. In Figure 1
the circular grainer is set up and operated by a through continuous current, like that
described in said United States Patent of October 19 1886 before referred to. In
Figure 3 the grainer is shown in detail being a section of one half. In this grainer R
are the arms L the scrapers, W the flippers U the agitator arms which carry the
flippers. Pare a series of pipes placed in the grainer about four inches below the
surface of the brine in it, extending across and around it and supported to
the outside of it so as to require no support in the interior of the grainer to interfere
with the rotation of the rakes. The superficial area of the pipes should be equal to
two-thirds the superficial area of the surface of the brine covering them. These
pipes are supplied with steam from any source, and the condensation may be used
as feed water. D, A, M is a strip of wood or metal reaching from the centre of the
grainer above the pipes, (and secured to them if they are used) to the outside of
it and of such width as to be about four inches in the brine and about the same
above.
Figure 4 is a top view of the suction box through which the brine flows from the
grainer H through the suction pipe Ps into and through the heater C and to the
circulating pump A. The suction pipe P is enclosed in a steam tight casing whereby
the brine is heated in its passage through the suction pipe.
P is a pipe through which fresh brine is pumped from the tank Z into the upper
end of the suction pipe P³ and from which it is passed into and through the heater C
to the pump A³ and from thence through the system continuously.
Figure 5 sheet 2, is a detail of one flipper or pendant agitator. It is composed of
the top supporting piece of connected to the metallic piece'd by a chain c and also to
the arm Was shown in figure 1. They are hung so that when revolved, they just
touch the surface of the brine in the grainer, and forcibly strike and pass over the
upper edge of the dam.
In sheet 2 is shown the arrangement for purifying the salt of non-crystallizable
soluble impurities. T' is a tank to hold the washing solution N³. A hose N' with
stop cock and nozzle to supply it to the salt in the centrifugal C. M is a mixer
whose contents are agitated by the shaft S and gear. G. D is a pipe leading from
centrifugal into and out of a vessel X¹ to a tank Z. It is obvious that if the
mixer M be attached to the grainer H in the place of the mixer L shown in
figure 1, then this apparatus would be used in connection with my system as there
shown. But it is obvious that salt may be treated by these appliances even if made
from any other apparatus. The operation is as follows:-
The grainer being filled one foot deep with brine, the closed evaporators partly
filled and the heaters and gravel boxes filled, the pumps A' and A³ are started, steam
is applied from a steain boiler, to either the heater A or A¹ whichever is in use; it
being intended to use one heater and gravel box while the other is opened for
cleaning. The brine highly heated in the heater A passes into and through the
gravel box, under hydraulic pressure regulated by the valve V. It then passes into

page_text: the evaporator E and thence into the grainer in which it circulates around the circle.
The dam prevents cross currents, as the hot brine entering the grainer at 226 degrees
Fahrenheit flows rapidly and spreads over the top of the grainer, and would pass
out at the discharge pipe without proper evaporation and cooling without it. As
the salt forms on the surface of the brine in small crystals, the flippers strike it,
making it sink to the bottom of the grainer, thus preventing it from enlarging while
retaining the natural crystal of the salt and making the proper size for family and
dairy use. Such salt would be known to the ordinary manufacturer of salt as mush
salt, and cannot be successfully drained, except by a centrifugal apparatus. Months
of standing in bins has no effect on it except to form a hard crust upon its surface.
Salt also will form in small crystals on the surface of the flipper plates, and if not
prevented would soon accumulate and load down the plates then their action would
be different, causing a different kind of agitation, and thus as their weight gradually
increased, changing the kind of salt produced in the apparatus. But as the agitators,
arms and flippers are revolved rapidly, the latter strike the dam forcibly, and so
continually knock off the salt as fast as formed, keeping the plates clean, and thus
securing a regular and complete action and a smooth, even and regular product,
which in a factory is of great importance. If it be desired to change the size of the
crystals, it may be done by changing the rapidity of the rotation of the arm carrying
the flippers, or by increasing or decreasing the number of the 'flippers as desired.
It is obvious that a rod might be used in place of the dam and it would produce the
same action, that is, of cleaning the flippers; the necessity being simply an obstruction
placed at or slightly above the brine level so as to make a forcible impact with the
flippers. The agitators and flippers revolve in opposite directions to the current in
the grainer, to prevent a swivelling action which is objectionable.
The scrapers and arms revolve with the current at a slower rate of speed, and
compel the circulation of the brine around 'the grainer. As soon as the salt is
formed, they sweep it from the centre to the outside of the grainer, sideways and
ahead into the mixer continuously, the scraper being so placed as to act like a screw
or scroll. From the mixer, the salt goes into the centrifugal and if containing no
soluble impurities, is passed along through a dryer and bolts until finished. The
elevators dryer and bolts may be of any ordinary construction. If the salt is made
from brine containing the chlorides of lime or magnesia, in such quantities as to
impair the value of the product; or if the brine under treatment contain them in
such quantities as to, by their accumulation in the grainer, compel its contents to be
thrown away from time to time, in many cases as often as every three days, and in
order to make my apparatus operate continuously, avoiding such stoppage, I arrange
by the tank a perforated pipe N° Figure 6 to wash the salt while in the centrifugal,
with brine directly from the spring or well, or with depurated brine, made from
dissolved salt. This I do in the centrifugal or I discharge the salt into a mixer from
the centrifugal, by an elevator or otherwise, and again mix and wash and separate
it, in like manner.
To prevent the accumulation of chlorides of lime or magnesia which may occur in
the brine under treatment, to such an extent as to impair the proper action of the
process, and which remain soluble in the brine we provide apparatus as shown in
detail in sheet 2. At each charge of the centrifugal, the vessel X is filled by the
brine, passing into it to the tank Z; and at each such charge, the contents of
the vessel are let run to waste, by means of a valve and handle as shown. The
vessel X should be of the proper size to throw away enough brine to prevent the
excessive accumulation of the chlorides in the grainer. If the salt needs the treatment
of chemicals, they can be supplied to the tank T and be applied to the salt while in
the centrifugal. The brine having circulated around the grainer, depositing salt by
evaporation and also by cooling goes into the steam-heated pipe P³ connecting the
suction box and heater C, and from the heater to the pump A, from which it is
again passed through the heaters C, B and A and into the gravel boxes and evaporators
continuously.
The object in heating the brine after it leaves the grainer by the encased pipe

page_text: and heater C, before it enters the pump, is that the brine cannot be pumped if
allowed to cool. Salt will form in the pipe and also in the pump and prevent its
action; but by heating the brine, its capacity for salt is increased and a small
amount of cooling as in passing the pump is permissible. For the same reason I
supply the fresh brine partly heated from the tank Z into the mouth of the suction
pipe, because it will take up and absorb any salt carried over mechanically. The
purification of the brine from crystallizible impurities, such as the sulphate and
carbonate of lime, is effected.a as follows:-By heating the brine in the heaters A
and A¹ to about 300 degrees Fahrenheit the lime becomes insoluble and crystallizes
in characteristic crystals. These adhere to surfaces presented to them, and from this
arises the difficulty usually experienced in the manufacture of salt the heating surfaces
become covered, action is thereby impaired, and the apparatus burns out, or the
apparatus requires to be stopped for cleaning out and renewal.
The purifiers or gravel boxes are made of boiler plate secured at top and bottom
by hinged doors, made to open and close easily. The purifiers are tapering, largest
at the bottom, so as to easily drop out the gravel, with which they are filled. This
is used, because it furnishes a nucleus for the small crystals and they deposit evenly
upon its surface in successive layers. If the brine contains one-half of one per cent.
of lime, and the factory makes one hundred and fifty barrels salt per day, the gravel
box will have to be opened and the contents taken out, once in about thirty six hours,
to prevent its solidifying completely. This is conveniently done by opening the
hinged door at the bottom, let the stones fall into the receiver F, to be elevated into
the upper receiver F¹, from whence they are again put into the gravel box for
further use.
The gravels are effective from one-half-inch to two inches diameters;
when longer, the lime envelope may be broken off and its pieces used with the
gravel. The brine being under pressure, pervades all parts of the purifier, around
the gravel, and in the interstices between them. There is no possibility of a stoppage,
as would often occur with a porous filter or one composed of fibrous material. The
action is certain and positive. Salt made in this apparatus using these purifiers,
analyzes 99.7 chloride of sodium, 044 lime, the remainder being water. Two of
these gravel boxes are provided, so that one can be used, while the other with its
accompanying heater can be opened and cleaned, making the action continuous.
small proportion of lime is deposited on the tubes of the heaters which is removed
every twelve to twenty four hours.
A
Referring to the detail of the grainer in figure 3, the same arrangement of coil
may be used in connection with my method of through circulation and heated currents,
and simultaneous with them. Usually, however, I prefer to use the apparatus without
the coils of the grainer, when the through currents of circulation are used through the
heaters, evaporators, purifiers, and grainer. And if the coils for heating be used in
the grainer, I prefer to use them as the sole heating medium, evaporating the brine in
the grainer entirely by them, using, however, in connection, the rakes, and agitator,
and mixer with or without the purifier as desired. I am aware that agitators have
heretofore been used for agitating brine in evaporating vessels. But I am not aware
that they have been used in the combination as described, or that any self-cleaning
automatic agitator has heretofore been produced. I am also aware that scrapers have
been used to scrape out the contents of salt grainers; I am not aware that any such
scrapers have been heretofore used as in the present case. Attempts have been made
to purify brine by blowing live steam into it to heat it, but I disclaim such an
arrangement as the present method requires the brine to be heated in tubular heaters,
in which the brine and steam are kept separate.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed as communicated to me by my
foreign correspondents I declare that what I claim is :-
First. The combination of the gravel box F, the closed evaporators D and E, the
open grainer H, the pipes P, the shaft K, and the rotating arms R provided with
scraper L in the manner as and for the purpose described.

page_text: Second. The combination of the grainer H, the pipes P, the rotating arms R,
having scraper L, the shaft K, the shaft T, the agitator arms W, provided with flipper
in the manner as and for the purpose described.
Third. The combination of the gravel box F, the heaters A and B, the evaporators D
and E, the grainer H the heater C with the pump A and connecting pipes, in the
manner as and for the purpose described.
Fourth. The dam in combination with the grainer H, the pipes P and the inlet
and exit pipes P1 and P3 in the manner as and for the purpose described.
Fifth. The dam in combination with the grainer H, the flippers W, the arms U and
means and for supporting and rotating them in the manner as and for the purpose
described.
Sixth. The combination of the tubular steam heated heaters A, B, the gravel box F,
the evaporators D and E, the grainer H, the heater C, with the pump A*, and
connecting pipes in the manner as and for the purpose described.
Seventh. The combination of the grainer H, the agitator arms W, the pendant
parts f, c, d, and the shaft T, in the manner as and for the purpose described.
Eighth. The combination of the heaters A, A¹, with the gravel boxes F, G, the
heater B, the pump A' and connecting pipes in the manner as and for the purpose
described.
Ninth. The combination in a grainer, of a series of rakes provided with scrapers
submerged in the brine, a series of agitators provided with flippers above the brine,
and shafts T and K, in the manner as and for the purpose described.
Tenth. The combination of the grainer H, the suction pipe P' the jacket pipe S'
enclosing it; the heater C, and the pump A³, in the manner as and for the purpose
described.
Eleventh. The combination of the pump A³, the pipe P with the pipe P³, the
heater C, pump A³, and connecting pipes, in the manner as and for the purpose
described.
Twelfth. The combination of the grainer H, the inlet pipe P¹ the exit pipe P³ the
pipes P, the dam, the rotating arms having scrapers and the agitating arms provided
with flippers in the manner as and for the purpose described.
Thirteenth. The combination of the heaters A, A¹, the gravel boxes F, G, the
evaporators D, E, grainer H, heating pipes P, suction pipes P, heaters B and C,
with the pump A³, and connecting pipes in the manner as and for the purpose
described.
Dated this 0th day of April 1889
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.