IMPROVEMENTS IN THE MANUFACTURE OF SALT, AND IN APPARATUS OR APPLIANCES EMPLOYED THEREIN.
Year: 1873

page_text: LETTERS PATENT to Otto Ernest Pohl, of Liverpool, in the County
of Lancaster, Salt Manufacturer and Merchant, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OF SALT, AND IN APPARATUS OR
APPLIANCES EMPLOYED THEREIN.
"
Sealed the 17th October 1873, and dated the 25th April 1873.
PROVISIONAL SPECIFICATION left by the said Otto Ernest Pohl at
the Office of the Commissioners of Patents, with his Petition, on
the 25th April 1873.
I, OTTO ERNEST POHL, of Liverpool, in the County of Lancaster, Salt
Manufacturer and Merchant, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE MANUFACTURE OF SALT, AND IN APPARATUS
OR APPLIANCES EMPLOYED THEREIN," to be as follows:-
In the process of evaporating salt brine to obtain common salt the
crystals are formed near the surface of the brine and afterwards allowed
to fall to the bottom of the pans, whence they are by the practises here- .

page_text: tofore followed raked out. The said practice is objectionable, inasmuch
as (1), the quality of the salt is not uniform; (2), fuel is wasted by there
being a layer of salt, a bad conductor of heat on the bottom; (3), there
is considerable first waste of material by the formation of so called pan
scale; and (4), the pans and appliances are rapidly deteriorated.
Now the object of my Invention under the first part is to obviate the
disadvantages named. For this purpose I remove the salt crystals from
amongst the brinc before they reach the bottom of the pan by travelling
collectors.
The apparatus which I employ consists essentially of bands, combined
chains, and boards, or their equivalents, made to travel horizontally or
nearly so, constantly or intermittently amongst the brine. In practice
one, two, or more chains carried on a horizontal axis or ön horizontal
axes is or are fitted with boards of timber, metal, or rigid material, and
caused to travel and collect the salt which, when the boards reach the
end, is delivered into a trough or well or on to a band or its equivalent,
travelling at a right angle. By the latter mode of delivery the salt is
conveyed away directly to the drying kilns or warehouses.
To take up slack of the chains set screws passed through the pans
from the outside are provided to move the bearings.
To prevent the salt crystals from falling between the longitudinal
openings when series of bands or chains and boards or their equivalents
are used, I ercct stationary angular sheds or pieces over them to deflect
the salt on to the travelling collectors.
The second part of my Invention has for its object to economically
remove salt from pans by mechanical appliances. I give motion to a
band or chain on a vertical axis, and affix a scraper or scrapers thereon.
The said scraper or scrapers remove the salt to the ends of the pans,
whence it is removed by hand appliances or by a travelling band or
its equivalent. Series of bands or chains and scrapers on vertical axes
can be used.
The third part of my Invention consists in applying brick arches
over the fire-places of evaporating pans on brick columns so as to
prevent the flames from objectionably attacking the bottom of the
pans.

page_text: In combination with the said brick arches I sometimes as means for
promoting more effective combustion fit a network of bricks at the
sides of the fire-places, and admit air through the said brickwork.
Before entrance into the firc-place the air becomes highly heated.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Otto Ernest Pohl in the Great Seal Patent Office
on the 25th October 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, OTTO ERNEST
POHL, of Liverpool, in the County of Lancaster, Salt Manufacturer and
Merchant, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-fifth day of April, in the year
of our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Otto Ernest Pohl, Her special licence
that I, the said Otto Ernest Pohl, my executors, administrators, and
assigns, or such others as I, the said Otto Ernest Pohl, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for " IMPROVEMENTS
IN THE MANUFACTURE OF SALT, AND IN APPARATUS OR APPLIANCES EMPLOYED
THEREIN, upon the condition (amongst others) that I, the said Otto
Ernest Pohl, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should par-
ticularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same
to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
"
NOW KNOW YE, that I, the said Otto Ernest Pohl, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
the following statement, reference being had to the accompanying two
'

page_text: =
Sheets of Drawings, and to the figures and letters marked thereon, that
is to say:-
In the process of evaporating salt brine to obtain common salt, the
crystals are formed near the surface of the brine and afterwards allowed
to fall to the bottom of the pans, whence they are by the practice here-
tofore followed raked out. This said practice is objectionable inasmuch
as (1), the quality of the salt is not uniform; (2), fuel is wasted by
there being a layer of salt, a bad conductor of heat on the bottom; (3),
there is considerable first waste of material by the formation of so called
pan scale; and (4), the pans and appliances are rapidly deteriorated.
Now the object of my Invention under the first part is to obviate the
disadvantages named. For this purpose I remove the salt crystals from
amongst the brine before they reach the bottom of the pan by travelling
collectors.
The apparatus which I employ consists essentially of bands, combined
chains and boards, or their equivalents, made to travel horizontally or
nearly so constantly or intermittently amongst the brine. In practice
one, two, or more chains carried on a horizontal axis or a horizontal
axes is or are fitted with boards of timber, metal; or rigid material, and
caused to travel and collect the salt which, when the boards reach the
end is delivered into a trough or well or on to a band or its equivalent
travelling at a right angle. By the latter mode of delivery the salt is
conveyed away directly to the drying kilns or warehouses.
To take up slack of the chains, set screws passed through the pans
from the outside are provided to move the bearings..
To prevent the salt. crystals from falling between the longitudinal
openings when series of boards, or chains and boards, or their equivalents
are used I erect stationary angular sheds or pieces over them to deflect
the salt on to the travelling collectors.
The second part of my Invention has for its object to economically
remove salt from pans by mechanical appliances. I give motion to a band
or chain on a vertical axis, and affix a scraper or scrapers thereon. - The
said scraper or scrapers remove the salt to the ends of the
pans, whence it
is removed by hand appliances or by a travelling band or its equivalent.
Series of bands or chains and scrapers on vertical axes can be used.

page_text: over the fire-places of evaporating pans on brick columns so as to prevent
the flames from objectionably attacking the bottom of the pans.
In combination with the said brick arches I sometimes, as means for
promoting more effective combustion, fit a network of bricks at the sides
of the fire-places and admit air through the said brickwork. Before
entrance into the fire-place the air becomes highly heated.
DESCRIPTION OF THE DRAWINGS.
On Sheet A Fig. 1 is a longitudinal section; Fig. 2, a plan view, part
only of the endless chain board collectors being shown; Fig. 3, a
transverse section; and Figs. 4, 5, 6, 7, 8, and 9, views of parts drawn to
a larger scale, all of salt crystal collecting apparatus; Fig. 4 is a
transverse section of an angular shed; Fig. 5, a transverse section of a
chain and collecting boards; Fig. 6, a side elevation and section of
transverse collecting chain and guiding piece; and Fig. 7, a view
showing a method of driving the bands; Fig. 8, a side elevation of a
portion of the chain and board, and triangular pulley or tumbler
carrying the chain; and Fig. 9 is a front view of the said pulley or
tumbler. These pullies or tumblers may be made with more than three
sides. In all these views like letters denote the same parts.
a denotes the lower evaporating pan; b, top evaporating pan sup-
ported on columns c; d, fire-place; e, chimney; f, chain of one endless
travelling collector; in the modification shown, transverse wood boards ġ
are secured to the chain by the pieces h, and it is proposed to use a
series of three chains each fitted with boards. Motion is given to the
chains and boards g by the transverse shaft i, whereon a wheel j is
secured; this wheel gears with a worm k on the first motion shaft 1.
Instead of the endless travelling collectors being made to travel con-
tinuously an intermittent motion may be given to them, and instead of
chains and boards flexible bands of woolen or other material or their
equivalents may be used, and such bands may be the full width of the
pan as the boards might be if desired; m, transverse chain; n, boards
forming a carrier for conveying away the salt to the drying room or
warehouse. Motion is given to the said carrier from a shaft o gearing
through wheel p with wheel q on the first motion shaft 1. The
carrier m, n, moves underneath the end of the travelling collectors and
-

page_text: receives the salt crystals dropped therefrom. To convey the salt
upwards out of the pan pullies are placed on the bolts which connects
the links of the chain; these bear on the ends of the stationary piece p.
In like manner pullies s are employed to keep that part of the chain for
'the time being the lower part at the proper distance.
It will be evident that the carrier described may be made of endless
flexible material and carried over rollers. t, stationary triangular
deflecting sheds carried by the supporting pillars and boards . Tie
rods or other convenient means can be used; guiding rods are employed
to prevent the boards locking each other or floating.
It will be obvious that although my salt crystal collecting apparatus.
is only shown applied to the upper pan, it could with advantage be also
applied to the lower pan, and in practice I prefer that it should be so
employed. Pieces are secured to the boards on the endless travelling
bands to act as scrapers should any salt crystals reach the bottom of the
pan.
To prevent the salt deposited on the cross carrier from being removed
therefrom by currents in the brine, I erect a shield on each side of the
cross carrier. The said shields are provided with ribs on which the ends
of the board slide. The whole representing a box of which the carrier is
a moveable bottom.
On Sheet B, Fig. 10 is a plan view of my apparatus for removing salt
from rectangular pans; 1, endless chain which has secured thereto the
scrapers 2; 3, cogged pullies on vertical axes around which the chain 1 is
carried. The enlarged view 11 shows how the scrapers are secured to
the chain and how they work round the pullies 3.
The above described collecting apparatus receives motion from one of
the pullies 3 and scrapes the salt into the pocket 4, whence it is removed
by hand, a travelling collector, or otherwise.
It will be obvious that endless bands of flexible material might be
used instead of the chain, and that the position of the pullies and pocket
and the form of the scrapers might be varied, or the pocket might be
dispensed with.
Fig. 11 (Sheet B) is a sectional side view, and Fig. 12 a sectional
front view of my improved furnace, part of the pans being shown. In
these views like figures denote the same parts. 5, top pan; 6, bottom

page_text: OTTO ERNEST POHL. (L.S.)