Improvements in and relating to Apparatus for Evaporating Solutions containing Salts, and for other Liquids
Year: 1890

page_text: Date of Application, 19th June, 1890
Complete Specification Left, 18th Mar., 1891-Accepted, 13th June, 1991
PROVISIONAL SPECIFICATION.
Improvements in and relating to Apparatus for Evaporating
Solutions containing Salts, and for other Liquids.
I, JAMES FOSTER, of Baltic Chambers, Sunderland, in the County of
Durham, Engineer, do hereby declare the nature of my invention to be as
follows:-
This invention has reference to and comprises a new or improved construction or
arrangement and combination of the parts of apparatus of the nature of triple or
multiple effect for evaporating liquids, and especially for evaporating solutions
containing salts, at different degrees of temperature according to the heat of the
steam used and the vacuum in the different vessels, and the removing of these
salts after precipitation from the several vessels individually or collectively; and
which will be more simple and efficient than such apparatus as heretofore
constructed.
Under one arrangement of my improvements as applied to an evaporating
apparatus of the nature of triple effect, for evaporating solutions containing salts,
three vertical cylindrical vessels are used, with their tubular steam heater in a
lower section and the evaporating chamber in the upper section, with the upper
steam and vapour heating pipes, and single or double stand pipes between each
vessel, leading the vapour evaporated in the one vessel to the heating chamber of
the next by double lateral branches at the lower end of the stand pipes at right
angles to each other radially towards the centre of the tubular heater, all so far
substantially the same as described in the vertical arrangement of evaporators
shown on Sheet 3 of the drawings of Applicants Specification of Patent
No. 7343 May 2 1889.
The improvements of the present invention consist first in forming a short
conoidal or curved discharge bottom part below the lower end tube plate of each
vessel with a large outlet branch in the centre projecting downwards, and with a
large hollow circular horizontal discharge valve chest with branch also projecting
downwards, which valve would have its spindle projecting out through a stuffing
box in its chest at one end, and be rotated by screw, toothed, or other gearing at a
slow rate, to automatically and continuously turn the valve and discharge the
contents at intervals of time when the saline solution was sufficiently treated to the
degree of concentration desired. The discharge branch of each valve chest might
either discharge into one common horizontal discharge pipe or duct placed
longitudinally below the centre of all the vessels, or into transverse T branches
leading to two different longitudinal horizontal discharge pipes common to all the
discharge valve chests, each T branch being fitted with a valve, so as to discharge
the contents down into one or other of the common discharge pipes, to draw off the
concentrated or precipitated salts treated at different temperatures or densities
into one or other of these side discharge pipes. These horizontal discharge pipes
would be formed with branches below each valve with closing lids or flanges, for
enabling these and their vertical discharge branches being cleaned out when
required; and they would preferably be provided with narrow openings and
covers above between these branches, for cleaning out the longitudinal discharge
pipes, which are or may be fitted with longitudinal rotating shafts in the centre,
and antifriction spiral rod or vane transmitters, the shafts being actuated by
pulleys on the spindles outside the inner close stuffing box end, while the other
end would be fitted with a discharge branch and valve where the saline solution or
salts would be discharged into suitable elevators to convey same to centrifugal or

page_text: other drying or treating machines from which they would be taken as finished
products.
A further improvement consists in fitting within each evaporating vessel, a
central rotating agitating and cleaning shaft down through a stuffing box in the
upper part, and actuated by bevel wheel or other gearing from one common
longitudinal shaft mounted over the whole set of evaporators, and actuated by
bands or other power transmitting gearing from any motive power shaft. This
central shaft would pass down one of the central small ascending liquid tubes and
be carried in a bearing at its lower end, and have mounted on this end, screw or
angled vanes for agitating the liquid, and also curved or angled radial scrapers
working close to the surface of the curved or angled bottom to prevent the deposit
or incrustation of the salts, or remove same off the inner surface of the discharge
part of the vessel. While similar vanes would be mounted on this shaft to rotate
close over the upper end tube plate of the heater, to prevent the precipitation of
salts over the plate, or the removing of same if deposited; or the upper surface of
the tube plate might be cast hollow between the tubes and bevelled conoidally
towards the upper end of the tubes, or have a loose plate fitted over it of this
angled character to prevent deposit on the upper tube plate. The saline solution
would circulate up through the small heating tubes from the lower discharge end of
the evaporator, and return down through one or two larger tubes fitted through
the tube plates at the colder opposite side of the evaporator to where the heating
steam or vapour entered. The large discharge rotating valve might have a fixed
agitating vane within it, which would keep the concentrated salts or liquid in
motion by the rotation of the valve and prevent deposit within it or remove any
if deposited; and to enable the valve to be freely turned and yet be liquid tight.
it would preferably have longitudinal strips or packings fitted in the working face
of the valve case, close to the inlet and discharge ports or branches; and in some
cases instead of this rotating valve, longitudinal slide valves might be fitted over
transverse ports formed in the discharge valve case, reciprocated to close or open
the ports automatically as described by screw or other reciprocating rods connecting
the valves for drawing off the concentrated liquid or salts as described. The saline
solution or liquid to be treated would be fed into the first vessel or it might be
into any one of the vessels as desired, from a common service pipe and cistern, by
lateral branches preferably to the lower part of each evaporator, and each fitted
with regulating and shut off valves or cocks; and a large branch from the top of
the last evaporator would lead the vapour to the condenser in the usual manner
of triple effects. Pipes would or might also be fitted leading from the lower end of
each vessel over the discharge valve, to lead the concentrated liquid of one vessel,
up into the upper or lower part of the next vessel, by the difference of vacuum
within, and fitted with cocks or valves to regulate this admission, and with end
branches and flanges at the knees for cleaning out any deposit of salts in these
pipes. And separate drawing off cocks would also be fitted at the lower part of
these evaporators or their pipes, specially useful for taking tests of the density of
the liquids being treated, and also suitable for drawing off the washing water, and
sight tubes or glasses would be fitted to the lower part or sides of each evaporator
to show the height and state of the liquid.
Dated the 18th June 1800

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to Apparatus for Evaporating
Solutions containing Salts, and for other Liquids.
I, JAMES FOSTER, of Baltic Chambers, Sunderland in the County of Durham,
Engineer, do hereby declare the nature of my invention, and in what manner the
same is to be performed to be particularly described and ascertained in and by the
following statement in writing, that is to say :-
This invention has reference to and comprises a new or improved construction,
or arrangement and combination of the parts of apparatus of the nature of triple or
multiple effects for evaporating liquids, and especially for evaporating solutions
containing salts, at different degrees of temperature according to the heat of the
steam used and the vacuum in the different vessels, and the removing of these
salts after precipitation from the several vessels individually or collectively; and
which will be more simple and efficient than such apparatus as heretofore
constructed.
And in order that my said invention and the manner of performing or carrying
the same into effect or practice may be properly understood, 1 have hereunto
appended an explanatory sheet of drawings, in which the same reference letters
are used to indicate corresponding parts in all the figures where shown, the new
parts being indicated by italic letters. Figure 1 is a general plan view of two
parallel duplicate sets of my evaporating vessels 1, and 1, 2 working as triple
effects with the third vessel 3, which is shown larger than the others working in
combination with either or both duplicate sets, this latter being in direct communi-
cation with the air pump condenser 4 of the steam engine 5, the exhaust steam
from which, leads by the pipes 6 to the steam exhaust receiver 7 for heating the
first evaporators 1, 1, or any of the others. Figure 2 is a side sectional elevation
to a large scale of one of the evaporators shown in Figure 1, to show the
construction and details of the improvements.
Referring to these drawings:-Under one arrangement of my improvements as
applied to an evaporating apparatus of the nature of triple effect for evaporating
solutions containing salts, three vertical cylindrical vessels A in 1, 2, 3 or duplicate
sets of these, 1, 2 are used, as shown in Figure 1, each with their tubular steam
heater A in the lower section and the evaporating chamber A in the upper
section, with the upper steam and vapour heating pipes G, and with single or
double stand pipes G between each vessel A, leading the vapour evaporated in the
one vessel to the heating chamber of the next by the lower vertical branch G"
and double lateral branches G2, G3, at the lower end of the stand pipes G'at right
angles to each other radially on opposite sides towards the centre of the tubular
heater A'.
The improvements of the present invention consist first in forming a short
conoidal or curved discharge bottom part a below the lower end tube plate A" of
cach vessel A with a large outlet branch a' in the centre projecting downwards,
and with a large hollow circular horizontal rotating discharge valve and chest b
with inlet and outlet branches 612 also projecting downwards, which valve bhas
its spindle projecting out through a stufling box in its chest at one end, and is
rotated by screw, toothed, or other gearing e c' at a slow rate from a shaft ²
common to the whole, to automatically and continuously turn the valve b, b, and
discharge the contents at intervals of time when the saline solution was sufficiently
treated to the degree of concentration desired through the lower discharge
branch. The discharge branch 62 of each valve and chest b, b', would by a
lower branch with a sluice or other valve in it lead the intermittent discharge
from this branch from each evaporator of one or both sets 1, 1, or 2, 2, by a
pipe d to draw off the salts concentrated at different densities and temperatures to
the exhausters D' for fine salt, D' for rough grain salt, and D³ for fishery salt.

page_text: .
Or these branches may discharge into one common horizontal discharge pipe or
duct placed longitudinally below the centre of all the vessels; or they may
discharge into transverse T branches leading to two different longitudinal
horizontal discharge pipes common to any number of the discharge valve chests,
cach branch being fitted with a valve, so as to discharge the contents down into
one or other of the common discharge pipes, to draw off the concentrated or
precipitated salts treated at different temperatures or densities into one or other of
these side discharge pipes. These horizontal discharge pipes would preferably be
formed with branches below each valve with closing lids or flanges, for enabling
these and their vertical discharge branches being cleaned out when required; and
they would preferably be provided with narrow openings and covers above
between these branches, for cleaning out the longitudinal discharge pipes, which
are or may be fitted with longitudinal rotating shafts in the centre, and anti-
friction spiral rod or vane transmitters, the shafts being actuated by pulleys on
the spindles outside the inner close stuffing box end, while the other end would be
fitted with a discharge branch and valve where the saline solution or salts would be
discharged from the pipes common to the lower part of the whole or any number
of the evaporators into suitable elevators to convey same to centrifugal or other
drying or treating machines from which they would be taken as crystallized or
finished salt products.
A further improvement consists in fitting within each evaporating vessel A, a
central rotating agitating and cleaning shaft e, carried in upper and lower bearings e¹ ell
and actuated by lever wheels e above each by a transverse shaft e³ and gearing e¹
outside from one common longitudinal shaft mounted over and at one side of the
whole set of evaporators, the outer end of each shaft passing out through a
stuffing box in the top A³ of each evaporator A, the shafte being actuated by
bands or other power transmitting gearing from any motive power shaft. This
central shaft e of each vessel A passes down one of the small ascending liquid
tubes A in the centre of the heater A', and has mounted on its lower end curved
or angled radial scrapers a working nearly close to the inner surface of the
curved or angled bottom a to prevent the deposit or incrustation of the salts in this
lower part of the evaporator and it might be also to remove same off the inner
surface of the discharge part al of the vessel A, and screw or angled vanes may
be fitted on the lower end of this shafte for agitating the condensed liquids in the
bottom of these vessels in addition to the scrapers at. While similar vanes a² are
mounted on this shaft e, to rotate close over the upper end tube plate A2 of the
heater A, to prevent the precipitation of salts over the plate or for the removing
of same if deposited; or the upper surface of the tube plate A2 might be cast
hollow between the tubes and bevelled conoidally towards the upper end of the
tubes, or have a loose plate fitted over it of this angled character to prevent
deposit on the upper tube plate A2. The saline solution would circulate up through
the small heating tubes A from the lower discharge end a of the evaporator, and
return down through one or two larger tubes at A', fitted through the tube
plates A", A³, at the colder opposite side of the evaporator to where the heating
steam or vapour entered by the branches G2, G3, from the stand pipes G", cach
stand pipe preferably being fitted with special valves and valve chests G³, at the
top of the stand pipe and evaporators for controlling the admission and emission of
the heated steam or vapour to, and isolating any one of the evaporators A. Each
large discharge rotating valve b, b, as shown in Figure 2 may be formed of cross
webs fitted with spring or other packing strips to maintain tightness in their
bored chest between the divisions ³, so as to deliver portions of the condensed
liquid at each revolution, when that is desired, and the sluice valve in the branch
below opened; or the rotation of the cylinder may only agitate the liquid; or in
some cases when made hollow and cylindrical this valve may have an agitating
vane within it which would keep the concentrated salts or liquid in motion by the
rotation of the valve and prevent deposit within it or remove any if deposited;
and to enable the valve to be freely turned and yet be liquid tight, the longitudinal

page_text: strips or packings may be fitted in the working face of the valve case, close to the
inlet and discharge ports or branches 6" 6 and tightened up by pinching screws
from the outside of the valve case; and in some cases instead of this rotating
valve, longitudinal slide valves may be fitted over transverse ports formed in the
discharge valve case, reciprocated to close or open the ports automatically as
described by screw or other reciprocating rods connecting the valves for drawing
off the concentrated liquid or salts as described. The saline solution or liquid to
be treated would be fed into the first vessel 1, or it might be into any one of the
vessels 1, 2, 3, as desired, from a common service pipe and cistern, by lateral
branches preferably to the lower part of each evaporator, as indicated at A', and
each fitted with regulating and shut off valves or cocks; and a large branch from
the top A and branch G, of the last evaporator 3 would lead the vapour by a.
pipe G to the condenser 4 in the usual manner of triple effects. Branches at a³
and pipes would or may also be fitted leading from the lower end a of each
vessel A over the discharge valve, to lead the concentrated liquid of one vessel, up
into the branch A5 of the upper part of the next vessel, by the difference of
vacuum within, and fitted with cocks or valves to regulate this admission, and with
end branches and flanges at the knees for cleaning out any deposit of salts in
these pipes. Live steam pipes H would be fitted leading from the boiler to the
exhaust steam receiver 7, controlled by cocks or valves H', so as to supplement
the exhaust steam from the engine 5, especially for heating the first evaporators 1, 1,
when the exhaust steam was not sufficient. And pipes 8 with valves 9 might
lead the exhaust or the live steam from the receiver 7 direct to any one of the
heating chambers A' of the evaporators 2, 2, or 3, by a branch G the lower ends
of the branch G" and G2, G3, of each stand pipe G'. And separate drawing off
cocks may also be fitted at the lower part of these evaporators or their pipes,
specially useful for taking tests of the density of the liquids being treated and
also suitable for drawing off the washing water, when cleaning out the vessels;
and sight tubes or glasses would or may be fitted to the lower part or sides of each
evaporator to show the height and state of the liquid.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:-
First. The construction, or arrangement and combination of the parts of triple
or multiple effect apparatus for evaporating solutions containing salts, and other
liquids, formed or fitted with a discharge chamber at their lower end with valve
and valve chest, and with agitating fittings, and arrangements of delivery branches
and pipes, so as to deliver the salts at different densities and temperatures from the
several vessels, substantially as herein described in reference to and by way of
application shown in the accompanying drawings.
Second. In multiple effect or other close evaporating apparatus for salt or other
liquids the fitting and use of an inverted conoidal or curved discharge bottom part
or chamber below the end tube plate of each vessel, and with a discharge valve
and valve chest, substantially as and for the purposes herein described in reference
to and by way of application shown in the accompanying drawings.
Third. In multiple effect or other close evaporating apparatus for salt or other
liquids the fitting and use of rotating scrapers and agitating blades at the lower or
discharge end of the vessels to prevent the deposit of the salts, substantially as
herein described, in reference to and by way of application shown in the
accompanying drawings.
Dated the 17th March 1891.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.