Improvements in Apparatus for Evaporating Salt Water for Supplying Extra Feed for Marine Boilers.
Year: 1890

page_text: Date of Application, 24th Nov., 1890
Complete Specification Left, 24th Aug., 1891-Accepted, 26th Sept., 1891
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Evaporating Salt Water for
Supplying Extra Feed for Marine Boilers.
I, James Kerr, of 20 Thorndale Road, Waterloo near Liverpool, in the
County of Lancaster, Engineer, do hereby declare the nature of this invention
to be as follows :-
My present invention relates to apparatus for evaporating salt water for supplying
extra feed for marine boilers, and consists of certain improvements specially
applicable to the apparatus set forth in the Provisional Specification of my prior
application for Letters Patent, dated 18th April, 1890, and numbered 5891.
The apparatus set forth in my prior Provisional Specification aforesaid, consists,
broadly, of an upright outer vessel, flanged at both ends, and an inner vessel of
smaller diameter, closed at the bottom, fitted with a removable cover at the top and
jointed at the top to the outer vessel by an external flange which closes the top of
the annular space between the vessels, the outer vessel being jointed by its lower
flange on to the top of the main condenser and the annular space thus having free
communication therewith; the salt water to be evaporated is led into the inner
vessel, is evaporated therein, partly by the heat of the uncondensed vapour in the
main condenser which circulates freely in the annular space and partly by steam
of higher temperature admitted into a tubular heating coil fitted within the inner
ressel, and the vapour so generated is led through the cover of the inner vessel to
the minin condenser through an external vapont pipe and cock.
According to my present invention I modify the construction so that the inner
vessel is in free communication with the annular space between the vessels; with
this object I close the top of the outer vessel by a removable cover, I dispense with
the external flange of the inner vessel and I perforate the central part of the cover
of the said vessel. The vapour generated in the inner vessel thus passes to the
condenser through the annular space, giving back part of its heat to the water in
the inner vessel, and the exterual vapour pipe and cock are dispensed with. In
order that the apparatus may be isolated from the main condenser when desired. I
close the bottoin of the outer vessel and make the connection therewith to the
condenser through a cock or stop valve.
The inner vessel is preferably not secured to the outer vessel but simply rests
on the bottom thereof on feet so as to be readily removable.
The inlet and outlet of the heating coil within the inner vessel which pass steam-
tight through the. annular space are controlled by external cocks or valves, and the
outlet is led by a pipe to the main condenser. Below the coil, which is readily
removable, I place a removable pan for collecting sediment and scale.
I find that it is desirable to regulate the supply of feed water automatically, and
also that it is very undesirable to admit air along with the feed water into the
inner vessel, and I accordingly adopt the following feed arrangements ;-
The feed water which is drawn from the circulating discharge by the partial
vacuum within the evaporator, first passes into a vessel which I term an air
separator; this is a vessel with a large inlet at the top and a small outlet at the
bottom; as the capacity of the vessel is considerable in comparison with the flow
of water, any air mixed therewith has time to separate and pass off through the
large inlet. The feed water now passes through a stop valve to the feed regulating
valve chamber which communicates at its lower end by a pipe with the lower part
of the inner vessel, and at its upper end by a second pipe with the upper part of-
the outer vessel, so that the water always stands in the valve chamber at the same
level as in the inner vessel. The feed regulating valve is preferably a piston valve

page_text: and is controlled by a float within the valve chamber; any air that may still remain
mixed with the feed water can separate therefrom in the valve chamber and pass
up through the connecting pipe to the outer vessel, and as the inlet of the said pipe
thereto is at a lower level than the perforations in the cover of the inner vessel, the
said air will by preference descend direct to the condenser instead of entering the
inner vessel.
The valve chamber may if desired be incorporated with the water gauge mounting,
in which case the float which is tall and cylindrical is placed within the gauge
glass which is made of larger diameter than usual.
A drain cock for brining the evaporator is fitted to the lower part of the inner
vessel, together with an air cock for destroying the vacuum when required, or if
preferred, an ejector or brine pump may be fitted so as to permit of the brine being
withdrawn without interfering with the action of the apparatus.
I provide a continuous salinometer, consisting of a glass tube and mountings
closely resembling those of an ordinary water gauge, and containing two or three.
balls of suitable specific gravity; both communications with the inner vessel are,
however, below the water level and the inner end of the lower one is turned down
and that of the upper one upwards; in this way the upward convection currents
within the inner vessel will cause a continuous circulation within the salinometer
tube.
1
The ordinary mountings such as safety valve and pressure gauge are fitted and
I prefer to fix a transverse diaphragm of wire gauze or perforated plate or the
like across. the top of the inner vessel, immediately below the cover thereof, with
the object of preventing priming.
F
Dated this 1st day of November 1800
SLOAN & LLOYD BARNES,
26, Castle Street, Liverpool, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Evaporating Salt Water for
Supplying Extra Feed for Marine Boilers.
I, JAMES KERR, of 20 Thorndale Road, Waterloo near Liverpool, in the County
of Lancaster, 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 :-
My present invention relates to apparatus for evaporating salt water for supplying
extra feed for marine boilers, and consists of certain improvements specially
applicable to the apparatus set forth in the Complete Specification of my prior
Letters Patent, dated 18th April, 1890; and numbered 5891.
The apparatus set forth in my prior Specification aforesaid, consists, broadly, of
an upright outer vessel, flanged at both ends, and an inner vessel of smaller
diameter, closed at the bottom, fitted with a removable cover at the top and jointed
at the top to the outer vessel. by an external flange which closes the top of the
annular space between the vessels, the outer vessel, being jointed by its lower, flange
on to the top of the main condenser and the annular space thus having free
communication therewith; the salt water to be evaporated is led into the inner
vessel, is evaporated therein, partly by the heat of the uncondensed vapour in the
main condenser which circulates freely in the annular space and partly by steam of
higher temperature admitted into a tubular heating coil fitted within tlie inner
vessel, and the vapour so generated is led through the cover of the inner vessel to
the main condenser through an external vapour pipe and cock.,
According to my present invention I modify the construction so that the inner
vessel is in free communication with the annular space between the vessels; with
this object close the top of the outer vessel by a removable cover,.. I dispense

page_text: with the external flange of the inner vessel and 1 perforate the cover of the said
ressel. The vapour generated in the inner vessel thus passes to the condenser
hrough the annular space, giving back part of its heat to the water in the inner
ressel. and the external vapour Dive and cock are dispensed with. In order that
the apparatus may be isolated from the main condenser when desired, I close the
bottom of the outer vessel and make the connection therewith to the condenser
hrough a cock or stop valve.
The accompanying drawings show an evaporator incorporating my present
the apparatus may be isolated from the main condenser when desired, I close the
bottom of the outer vessel and make the connection therewith to the condenser
through a cock or stop valve.
The accompanying drawings show an evaporator incorporating my present
improvements;
Fig. 1 is a sectional elevation on the line A A of Fig. III,
Fig. II is a front elevation,
Fig. III is a sectional plan on the line B B of Fig. 1,
Fig. IV is a sectional elevation of the feed regulating valve chamber to an
enlarged scale and
Fig. V is a sectional elevation of the air separator.
Throughout the drawings similar parts are indicated by the same reference
figures, and in the case of sections, the direction in which they are viewed is
indicated by the small arrows placed adjacent to the letters denoting the plane of
section.
is the outer and 4 is the inner vessel, 7 being the annular space between the
vessels the bottom 2 of the outer vessel is jointed to the upper flange of the stop
valve 3 and the lower flange of the said valve is jointed to a suitable opening on
top of the main condenser, so that the space 7 can be put in communication with
the vapour space of the main condenser or isolated therefrom at will.
The outer vessel is closed with the removable cover 5 and the inner vessel is
fitted with the loose cover 8. which rests upon the ring 6 and is retained in position
by the spring 10; the cover 8 is perforated at 14 so that the interior of the inner
vessel communicates freely with the space 7 and thence through the stop valve 3
with the vapour space of the main condenser.
The inner vessel is preferably not secured to the outer vessel but rests on the
bottom thereof on feet or on the bolt heads 16 so as to be readily removable.
13 is the steam inlet pipe to the heating coil 9 and 15 is the outlet from the
coil; the inlet and outlet are controlled by the stop valves 12 and 11 respectively.
The method of connecting the pipes 13 and 15 to the coil 9 is shown in Fig. 1;
the inner vessel is worked out where the pipes enter so as to touch the outer vessel
and the double ended screwed union 17 is firmly secured steamtight through the
double thickness of plate by the nut 21; this arrangement allows the coil to be
readily detached without moving the inner vessel or disturbing the outside
connections.
The heating steam for the coil is taken from the boiler or one of the cylinder
casings or other convenient source and the spent steam is led to the main condenser,
as shown, through the lower stem of the stop valve 3 so as to avoid further
connections to the condenser.
I find that it is desirable to regulate the supply of feed water automatically, and
also that it is very undesirable to admit air along with the feed water into the
inner vessel, and I accordingly adopt the following feed arrangements :-
:-
The feed water which is drawn from the circulating discharge by the partial
vacuum within the evaporator, first passes into the vessel 22 shown in Fig. V
which I term an air separator; this air separator has a large inlet 26 at the top,
jointed to the circulating pump discharge pipe or passage 27, and a smaller outlet 28
at the bottom, and as the capacity of the vessel is considerable in comparison with
the flow of water, any air mixed therewith has time to separate and pass off through
the large inlet. 29 is an internal pipe, closed at the top and perforated which acts
as a strainer. The feed water passes from the air separator by the pipe 28 and
stop valve 18 to the feed regulating valve chamber 30 shown in Fig. IV which
communicates at its lower end by the pipe 31 with the lower part of the inner
vessel 4 and at its upper end by the pipe 32 with the upper part of the outer

page_text: vessel 1, so that the water always stands in the valve chamber at the same level
as in the inner vessel; the valve chamber is fitted with the water gauge 19. The
feed regulating valve 33 is a piston valve and is attached by the hollow perforated
stem: 34 to the controlling float 35 which is guided above by the hollow perforated
stem 36; the feed water entering by the pipe 28 passes through the perforations
of the stem 34 to the pipe 31 and thence to the inner vessel; any air that may
remain mixed with the feed water after entering the valve chamber can separate
therefrom and pass through the perforations of the stem 36 to the upper part of
the outer vessel, and as the inlet of the pipe 32 to the outer vessel is at a lower
level than the perforation 14 in the cover 8 the said air will descend direct to the
condenser instead of entering the inner vessel 4.
20 is a drain valve for brining the evaporator and the inner end of the pipe 31
is fitted as shown in Figs. II and III with a short internal pipe reaching early to
the bottom of the inner vessel.
37 is a continuous salinometer consisting of a glass tube and mountings resembling
those of an ordinary water gange, and containing three balls of suitable specific
gravities so that the number of balls which float to the top indicate the density of
the water. As shown in Fig. Il both communications with the inner vessel are
below the water level and the inner end of the lower one is turned down and that
of the upper one upwards; in this way the upward convection currents within the
inner vessel will cause a continuous circulation within the salinometer tube.
23 is an air cock connected with the annular space 7 by the pipe 38, for
destroying the vacuum when required; as the pipes leading from the valves 11, 12,
18, and 20 and the air cock 23 are of small diameter and therefore not very rigid,
I steady these valves by fixing them to the bar 39 carried by a stem from the
upper flange of the valve 3.
The ordinary mountings such as safety valve and pressure gauge are fitted and I
fix a transverse diaphragm 40 of wire gauze or perforated plate across the top of
the inner vessel, immediately below the cover thereof, with the object of preventing
priming 24 is a pan resting on feet 25 for the purpose of collecting sediment
and scale 41 is a short tube passing steam-tight through both vessels and fitted
with the screwed cap 42, through which a rod can be introduced to break up the
scale in the inner vessel if it should accumulate to an excessive thickness; the
pan 24 may be cut away so as to stand clear of the tube 41 and the feet supporting
the coil 9.
It is to be understood that I make no claim herein to any of the subject matter of
my prior Letters Patent aforesaid which has been introduced herein in order to
illustrate the application of my present invention.
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:-
1. In apparatus such as is herein described, the combination of an outer closed
vessel opening at its lower end into the vapour space of the main condenser, an
inner vessel, supported concentrically within the outer vessel, and having a loosely
fitting perforated cover, so forming between the vessels an annular space communi-
cating with the vapour space of the main condenser, and a steam heating coil, the
inlet and outlet of which pass steam-tight through the vessels and communicate
respectively with a steam supply and the main condenser, substantially as
described.
2. In apparatus such as is herein described the feed regulating device shown in
Fig. IV consisting of a valve chamber containing a Hoat guided above by a
perforated stem aud below by a piston valve to which it is connected by a perforated
stem, the lower part of the valve chamber communicating with the lower part of
the inner vessel and the upper part with the annular space between the vessels at
a lower level than the perforations in the cover of the inner vessel substantially
as and for the purpose described and illustrated.

page_text: 3. In apparatus such as is herein described the air separator substantially as
described and illustrated in Fig. V.
4. The combination and arrangement of parts forming the improved apparatus
for evaporating salt water for supplying extra feed for marine boilers, substantially
as described and illustrated in the drawings.
Dated this 22nd day of August 1891.
SLOAN & LLOYD BARNES,
Castle Chambers, Castle Street, Liverpool, Agents for the Applicant.