Improvements in Evaporating Apparatus, Specially Adapted for the Extraction of Salt from Brine.
Year: 1890

page_text: Date of Application, 23rd July, 1890
Complete Specification Left, 21st Apr., 1891-Accepted, 23rd May, 1891
PROVISIONAL SPECIFICATION.
Improvements in Evaporating Apparatus, Specially Adapted for the
Extraction of Salt from Brine.
We, ALFRED CHAPMAN of 17 York Street, Liverpool, Engineer, and SAMUEL
VICKESS Junior of 163 Chatham Street, Liverpool, Engineer, do hereby declare
the nature of this invention to be as follows:-
The object of our invention is to construct an evaporating apparatus on the well-
known double, triple or multiple effect system and adapted more especially for the
extraction of salt from brine and the invention consists in the improved general
arrangement or combination of parts as hereinafter described and also in certain
minor combinations or improvements hereinafter explained.
We will proceed to describe the invention as applied to a quadruple effect
apparatus that is to say, an apparatus having four evaporating pans or vessels
working on the multiple effect system.
Each pan is fitted with a steam drum as usual and between the plates which form
the top and bottom of the drum are. a number of small tubes for the upward flow of
the brine while there is one large tube, preferably central, for the down flow, this
tube being carried some distance below the drum or bottom tube plate. The
bottom of each pan is in the form of an inverted cone with an outlet communicating
with a salt receiver below, the said outlet being fitted with a mitre or other valve.
Each salt receiver has a hinged valve door at the bottom.
Under the salt receivers
but not in direct communication therewith are filters or "tigers" such as are used
in some chemical works and for treating green sugar in some sugar works, that is
to say, tanks containing for a depth of from 9 to 12 inches gravel, stone chippings,
coke or the like in which is laid a perforated pipe or inverted canal connected with
an exhausting pump. These filters or tigers may if desired contain ordinary salt
tubs or moulds so that the salt may be drained and moulded at the same time.
In connection with the last pan of the series is a heater, a condenser, and a
vacuum engine, this engine being worked by steam from any suitable boiler and the
exhaust steam is conducted to the drum of the 1st pan as usual, the vapour
evolved from the brine in the first pan goes to the drum of the 2nd pan and so
on, the vapour passing from pan to pan in the manner well understood, and the
vapour from the last pan goes through the heater to the condenser which has an
air or vacuum pump attached to it as in ordinary multiple effect apparatus. The
water due to condensation of steam or vapour in each drum (except the last) is
conducted to the drum of the next pan preferably by a syphon arrangement of the
kind described in the Patent Specification of Alfred Chapman No. 2511 of 1888 so
that it may give up part of its heat in the next drum and the condensations from
the last pan are drawn off by a pump.
The brine to be evaporated is pumped into and through the heater and the pipe
by which it leaves the heater has branches communicating with the several pans,
each pan being thus fed separately with the brine. The feed branches are
connected with automatic feed vessels or feed arrangements of novel construction
in each pan. These feed arrangements consist of a double beat valve fitted in a
closed vessel which is connected by a small pipe with the upper part of the pan
and by a large pipe with the lower part of the pan; these 2 pipes maintain the
pressures within the pan and the feed vessel equal, and consequently the level of
the brine in the pan and in the vessel will be the same. Over the double beat
alve and connected directly to it is a float the weight of which combined with
that of the valve keeps the valve passage open as long as the brine level is below
he float but when the level rises to a given height it causes the float and valve to

page_text: rise and thereby close the valve passage thus cutting off the brine supply. The
brine flows up the small tubes in the drum and down the large one to the bottom of
the pan where there is least agitation and the salt precipitated falls through the
mitre valve, which is normally open, into the receiver below. The receivers are
large enough to hold the salt made or extracted during say an hour's work. When
a receiver has to be discharged (they should be discharged in rotation) the mitre
valve is first closed to cut off connection with the pan, an air valve is opened and
the hinged door to the receiver freed and the salt will then fall into the filter.
When a filter is full the exhausting pump connected therewith is put to work so as
to draw off the liquor which it discharges into the brine tank or other vessel.
After the salt has been discharged from a receiver the bottom door is closed and
the receiver is filled with brine by a branch pipe provided for the purpose before
the mitre valve is re-opened; therefore when this valve is reopened the brine level
in the pan will not be affected.
Instead of having a central down pipe as hereinbefore described the heating tubes
may be fixed in a separate drum the brine being allowed to flow down between it and
the side of the pan; or the brine may be taken down outside of the pan by a
suitable pocket or funnel and down pipe connected to the lower part of the pan, all
of which arrangements are well known.
Dated this 23rd day of July 1890.
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Patent Agent.
COMPLETE SPECIFICATION.
Improvements in Evaporating Apparatus, Specially Adapted for the
Extraction of Salt from Brine.
We, ALFRED CHAPMAN, of 17 York Street, Liverpool, Engineer, and SAMUEL
VICKESS, Junior, of 163 Chatham Street, Liverpool, Engineer, 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:-
The object of our invention is to construct an evaporating apparatus on the well
known double, triple or multiple effect system, and adapted more especially for the
extraction of salt from brine, and the invention consists in the improved general
arrangement or combination of parts as hereinafter described and also in certain
minor combinations or improvements hereinafter explained.
We will proceed to describe the invention as applied to a quadruple effect
apparatus, that is to say, an apparatus having four evaporating pans or vessels
working on the multiple effect system.
This apparatus is represented in the accompanying drawings of which Figure 1
is an elevation partly in section, and Figure 2 a plan. a, a, a³, a', are the four
evaporating pans each of which is fitted with a steam drum b as usual, and between
the plates which form the top and bottom of the drum, are a number of small
tubes c for the upward flow of the brine, while there is one large tube d, preferably
central as shown for the downflow, this tube being carried some distance below the
drum or bottom tube plate. The bottom of each pan is in the form of an inverted
cone e with an outlet communicating with a salt receiver f below, the said outlet
being fitted with a mitre or other valve g. Each receiver has a hinged valve
door h or other suitable valve of any of the well known varieties at the bottom.
Under the receivers, but not in direct communication therewith, are filters or
tigers "i i such as are used in some chemical works and for treating green sugar
in some sugar works, that is to say, tanks containing, for a depth of from 9 to
12 inches, gravel, stone chippings, coke or the like, in which is laid a perforated
pipe or inverted canal (not shown) connected with an exhausting pump.
These
filters or tigers may if desired contain ordinary salt tubs or moulds, such as shown
in Figure 3, so that the salt may be drained and moulded at the same time.
66

page_text: l
In connection with the last pan at of the series is a heater j, a condenser (not
shown), and a vacuum engine (not shown), this engine being worked by steam from
any suitable boiler. The exhaust steam is conducted to the drum of the first pan
as usual, being admitted thereto at k; the vapour evolved from the brine in the
first pan a¹ goes by the main or pipe to the drum of the second pan and so on,
the vapour passing from pan to pan in the manner well understood, and the vapour
from the last pan goes through the main or pipe m to the heater j and from this
heater to the condenser which has an air or vacuum pump attached to it as in
ordinary multiple effect apparatus. The water due to condensation of steam or
vapour in each drum (except the last) is conducted to the drum of the next pan
preferably by a syphon arrangement of the kind described in the Patent
Specification of Alfred Chapman, No. 2511 of 1888, so that it may give up part
of its heat in the next drum, and the condensations from the last pan are drawn off
by a pump; or if the pan is sufficiently high the condensations from the last pan
can be run off by a pipe forming a Torricellian column in the way usual in such
cases. The tail pipe n attached to each drum leads the condensation water to the
corresponding syphon p which delivers it to the next drum, as seen in the figures.
The syphons are shown as having the part for the upward flow contained within the
part for the down-flow of the water, this being the preferred arrangement, but it is
not important.
The
The brine to be evaporated passes into and through the heater j entering it at
the bottom preferably by gravity from a tank fixed at a suitable level, and the pipe q
by which it leaves the heater at the upper part has branches communicating
with the several pans, each pan being thus fed separately with the brine.
feed branches r, r are connected with automatic feed vessels or feed arrangements
of novel construction in each pan. These feed arrangements consist of a double
beat valves (or other suitable valve) fitted in a closed vessel t which is connected
by a small pipe u with the upper part of the pan and by a large pipe with the
lower part of the pan; these two pipes u and maintain the pressures within
the pan and the feed vessel t equal, and consequently the level of the brine in the
pan and in the vessel will be the same. It is important that the pipe should
communicate with the lower part of the pan above the level of the end of the
tube d, so that the settling of the salt in the cone e may not be disturbed and an
upward current be produced where a downward one is wanted. Over the double
beat valves and connected directly to it is a float w, the weight of which combined
with that of the valve keeps the valve passage open as long as the brine level is
below the float, but when the level rises to a given height, it causes the float and
valve to rise and thereby close the valve passage thus cutting off the brine supply.
The brine flows up the small tubes c in the drum and down the large one d to the
bottom e of the pan where there is least agitation and the salt precipitated falls
through the valve g, which is normally open, into the receiver below. The
receivers are large enough to hold the salt made or extracted during say an hour's
work. When a receiver has to be discharged (they should be discharged in
rotation) the valve g is first closed to cut off connection with the pan, an air valve x
is opened and the hinged door to the receiver freed, and the salt will then fall
into the filter i. When a filter is full the exhausting pump connected therewith is
put to work so as to draw off the liquor which it discharges into the brine tank or
other vessel. After the salt has been discharged from a receiver the bottom door h
is closed and the receiver fis filled with brine by a branch pipe y provided for the
purpose before the valve is reopened; therefore when this valve is reopened
the brine level in the pan will not be affected. Or instead of filling the receiver f
with brine as described it can be filled with the mother liquor which has been
drained from the salt in the filters or tigers i; in this case the mother liquor from
the filters should not be discharged into the ordinary brine tank but into a separate
tank fixed at a convenient level to command the receivers f and connected to the
receivers by suitable piping and stop cocks.
Instead of having a central down pipe d, as herein before described, the heating

page_text: tubes c may be fixed in a separate drum the brine being allowed to flow down
between it and the side of the pan, or the brine may be taken down outside of the
pan by a suitable pocket or funnel and down pipe connected to the lower part of
the pan, all of which arrangements are well known.
Although we have described the apparatus as applied to the extraction of salt
from brine for which it has been specially designed it can be employed for the
evaporation of other solutions or liquors.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. The arrangement or combination of parts forming an improved evaporating
apparatus, substantially as herein before described and represented in the accom-
panying drawings.
2. The feed apparatus constructed substantially as hereinbefore described with
reference to the accompanying drawings, for supplying an evaporating pan or vessel
with the solution or liquor to be evaporated.
Dated this 20th day of April 1891
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Patent Agent.
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Patent Agent.