Improvements in and relating to Evaporators, Condensers, and the like for Producing Fresh Water from Salt or Impure Water.
Year: 1899

page_text: Date of Application, 18th Nov., 1899
Complete Specification Left. 16th Aug., 1900 - Accepted, 10th Nov., 1900'
PROVIDIONAL DECIFICATION.
Improvements in and relating to Evaporators, Condensers, and the
like for Producing Fresh Water from Salt or Impure Water.
We, DAVID ALEXANDER BLAIR and JAMES BARTON BLAIR, both of Scotland
Street, in the City and County of Glasgow, Manufacturing Coppersmiths, and
ROBERT BAILLIE, of 3, Kirkwood Street, Ibrox, Govan, in the County of Lanark,
Draughtsman, do hereby declare the nature of our invention to be as follows:-
This invention relates to improvements in and relating to evaporators, con-
densers and the like for producing fresh water from salt or impure water.
We will describe our invention as applied to evaporators, but it will be under-
stood that it is equally applicable to condensers and the like and we construct such
apparatus as follows:-
The evaporator consists of an upright cylindrical vessel in the lower part of
which a group or sheaf of straight cylindrical or other shaped tubes, is arranged
vertically, the tubes being secured into tube plates covered or boxed over with
closed dished ends, the top end or cover having a branch for inlet steam and the
bottom cover having a branch for outlet condensed steam, the tubes, tubeplates and
covers with branches making a complete chamber for evaporating the salt water
contained outside this chamber and inside the evaporator casing. The branches
on the top and bottom covers of the tube sheaf are connected by horizontal pipes
or ports either to the inside of the large door of the evaporator casing; or directly
sideways to the inside of the aforesaid casing and independent of the door, the
latter being provided on the side of the evaporator casing for the inserting and
with-drawing of the evaporating tubes and the examining of the inside of the
shell of evaporator. In the case where the sheaf of tubes is connected directly
to the steam inlet on the evaporator door, the pipe or port connecting the top on
inlet cover to the steam supply on the door is carried to the back of the cover
and also to the side of the cover and remote from the door, and that for the bottom
or outlet cover is carried from the front of the cover near to the door and side-
ways; but diagonally and opposite to the inlet of the top cover, the result being
that the orifice on the outlet branch is diagonally opposite to the inlet orifice on
the top cover, the effect of this arrangement of inlet and outlet being to equally
distribute the circulation of the steam inside the evaporating tubes or it may be
arranged that if the inlet orifice on the top cover is next the door and to the side
of cover, the outlet. orifice or branch on bottom cover will be remote from the
door and on the opposite side of cover, this being the reverse of the first mentioned
arrangement of cover branches.
Similar arrangements being carried out if instead of the sheaf of tubes being
secured or connected to the door by the cover ports or branches, it is directly
fixed sideways to the steam supply and outlet orifices on the sides of the evaporator
casing.
The steam supply and outlet branches, when secured to the evaporator door;
are connected by pipes or ports through and from the outside of the evaporator

page_text: The
door to branches on outside casing on which regulating valves are secured.
joints of these connections are made separate and independent from low pressure
joint of the evaporator door and being in line with the joint of the latter, these
joints will require to be broken when opening door. It will be seen that when
the tube sheaf is under steam, expansion and contraction; will take place ver-
tically between the outlet and inlet branches on covers, if they are placed in line,
but this is provided against by the diagonal disposition of these branches where
fixed on door and also by the spigots on branches and bolt holes being in the
line of the expansion and contraction and sufficiently clear to take up or move
under the above conditions of expansion and contraction.
The evaporating tubes are expanded into tube plates at both ends, but when
expanded plain into the plates they are liable to move in the hole through the
action of the expansion and contraction of the tube especially when cracking off
the deposit of scale on the outside of the tubes by the sudden application of cold
water to the hot tubes. To effectually secure the tubes against the above leakage
we insert a tapered tap with fine thread and tap the hole in tube-plate about three
fourths through; the plain tube being then expanded into this specially prepared
hole then it has a screwed and greatly increased surface imparted to its outside
part next the tube plate thus preventing any motion of tube and enabling thereby
a reduction of thickness of tube plate to be made.
The salt water evaporated and that discharged as brine is replaced by an
automatic regulated supply of the feed salt water by means of a box or casing,
on the outside of the evaporator, supplied with salt water through a side inlet.
In this box slides a hollow tube, or valve in a hole provided for it. This tube
or hollow valve has a hole in its side close to hole on side of box and tube
extends downwards into the inside of evaporator casing and is connected in the
inside of evaporator casing to a lever actuated by a float and so arranged that
when the water rises in the evaporator casing beyond the normal level, the float
in rising causes the hollow valve or tube to cut off or diminish the supply. The
hole, on the top side of the tube when full open, is in line with the hole on the
supply branch on box outside the casing of evaporator and the water entering
the side of the tube or valve is conveyed downward into the evaporator casing as
feed water. The fulcrum which is adjustable, is between the float and the valve
tube, the latter partly balancing the weight of the float. The fulcrum of float
lever being adjustable from outside the evaporator casing, the level of the salt
water inside the casing can be altered at will."
For the prevention of priming in the evaporator casing a short pipe or box
is attached close under the vapour outlet orifice inside the evaporator casing, the
sides of pipe being perforated, the top open and the bottom closed but connected to
a pipe to drain any water accumulating in the bottom of first mentioned pipe.
Near the bottom of the top pipe is fitted sideways an invented conical plate extend-
ing outwards to within a short distance of the inside of evaporator shell, the base
of the conical plate being upwards and the apex downwards and a similar smaller
conical plate and parallel to the first is fitted higher up on the side of the top pipe.
This arrangement will prevent the water rising up and through the vapour outlet.
The water thrown up by priming after passing the first cone is directed downward_
by the bottom of the top cone through the holes in the side of large pipe and it
will be then drained downward and back to an undisturbed part of the casing by
the smaller pipe fitted on bottom of large top pipe or vessel. The vapour will
pass freely round the bottom and top cone plates and up through the holes, at the
top of pipe or vessel close to vapour outlet.
Safety valves, gauge glasses and other mountings such as are common to all
types of evaporators are fitted as also a hand feed water inlet as well as the
automatic feed arrangement described.
In applying these improvements to act as a condenser, the steam tubes would
be carried to near the top of vessel, and the baffle plates, and automatic regulating
gear be dispensed with; while the outer vessel would preferably be formed in two

page_text: parts and be bolted together at centre of height, while the top and bottom tube
sheaf covers would be directly connected to the sides of outer shell of condenser.
Dated the 17th November 1899.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.
Improvements in and relating to Evaporators, Condensers, and the
like for Producing Fresh Water from Salt or Impure Water.
We, DAVID ALEXANDER BLAIR and JAMES BARTON BLAIR, both of Scotland
Street, in the City and County of Glasgow, Manufacturing Coppersmiths, and
ROBERT BAILLIE, of 3, Kirkwood Street, Ibrox, Govan, in the County of Lanark,
Draughtsman, do hereby declare the nature of our 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:-
This invention relates to improvements in and relating to evaporators, con-
densers, and the like for producing fresh water from salt or impure water."
And in order that our said invention and the manner of carrying same into
practice may be properly understood we have hereunto appended explanatory
drawings in which Figure 1 is a sectional elevation of an evaporator having our
improvements applied thereto.
Figure 2 is a horizontal section as taken on the line 2-2 of Figure 1.
Figure 3 is an external elevation at right angles to Figure 1 and Figure 4 a
plan view of Figure 3.
Figure 5 is a detached sectional elevation broken away, showing a tube being
expanded into a specially prepared tube plate. While Figure 6 is a detached
sectional elevation showing the arrangement of automatic feed.
Referring to these drawings.
We will describe our invention as applied to evaporators, but it will be under-
stood that it is equally applicable to condensers and the like and we construct
Such apparatus as follows:-
or
The evaporator consists of an upright cylindrical vessel. A in the lower part of
which a group or sheaf of straight cylindrical or other shaped tubes B is arranged
vertically, the tubes being secured into tube plates B 132 covered
boxed over with closed dished end covers B³, the top end or cover having a
branch for inlet steam, and the bottom cover having a branch 61 for outlet con-
densed steam, the tubes, tubeplates and covers with branches making a complete
chamber foevaporating the salt water contained outside this chamber and inside.
the evaporator casing. The branches b b on the top and bottom covers B3 of the
tube sheaf are connected either to the inside of the large door D of the evaporator
casing; or directly sideways to the inside of the aforesaid casing and independent
of the door, the latter being provided on the side of the evaporator casing for
the inserting and withdrawing of the evaporating tubes and the examining of the
inside of the shell of evaporator. In the case where the sheaf of tubes is connected
directly to the steam inlet on the evaporator door 1), the inlet branch b connecting
the top or inlet cover to the steam supply on the door being carried to the back
of the cover and also to the side of the cover and remote from the door, and that b¹
for the bottom or outlet cover B3 is carried from the front of the cover near to the
door and sideways; but diagonally and opposite to the inlet of the top cover, the

page_text: result being that the orifice on the outlet branch 61 is diagonally opposite to the
inlet orifice on the top cover, the effect of this arrangement of inlet and outlet
being to equally distribute the circulation of the steam inside the evaporating
tubes B; or it may be arranged that if the inlet orifice on the top cover is next the
door and to the side of cover, the outlet orifice or branch on bottom cover will
be remote from the door and on the opposite side of cover, this being the reverse
of the first mentioned arrangement of cover branches.
Similar arrangements being carried out if instead of the sheaf of tubes B being
secured or connected to the door D by the cover ports or branches, it is directly
fixed sideways to the steam supply and outlet orifices on the sides of the evaporator
casing.
The steam supply and outlet branches b b when secured to the evaporator door D
are connected by pipes or ports C C through and from the outside of the
evaporator door 1) to branches c c on outside casing on which regulating valves
would be secured. The joints of these connections are made separate and inde-
pendent from the ordinary joint of the evaporator door and being in line with
the joint of the latter, these joints will require to be broken when opening door.
It will be seen that when the tube sheaf B is under steam, expansion and con-
traction, will take place vertically between the outlet and inlet branches b b¹on
covers B3 if they are placed in line, but this is provided against by the diagonal
disposition of these branches where fixed on door 1) and also by the spigots on
branches and bolt holes being in the line of the expansion and contraction and
sufficiently clear to take up or move under the above conditions of expansion
and contraction.
The evaporating tubes are expanded into tube plates B 132 at both ends, but
when expanded plain into the plates they are liable to move in the hole through
the action of the expansion and contraction of the tube B especially when cracking
off the deposit of scale on the outside of the tubes by the sudden application of cold
water to the hot tubes. To effectually secure the tubes against the above leakage
we insert as shown in Figure 5 a tapered tap with fine thread and tap the hole in
tube plate B1 B2 about three fourths through; the plain tube then expanded into
this specially prepared hole has a screwed and greatly increased surface imparted
to its outside part B next the tube plate thus preventing any motion of tube and
enabling thereby a reduction of thickness of tube plate to be made.
The salt water evaporated and that discharged as brine is replaced as shown in
Figure 6, and dotted in in Figure 1 by an automatic regulating supply of the
feed salt water by means of a box or casing E on the outside of the evaporator A
supplied with salt water through a side inlet E¹. In this box slides a hollow
tube or valve e in a hole provided for it. This tube or hollow valve e has a
hole e in its side close to hole E¹ on side of box E and tube e extends downwards
into the inside of evaporator casing and is connected in the inside of evaporator
casing to a lever F actuated by a float F and so arranged that when the water
rises in the evaporator casing beyond the normal level, the float F in rising causes
the hollow valve or tube e to cut off or diminish the supply. The hole c on the
top side of the tube e when full open, is in line with the hole E on the supply
branch on box outside the casing of evaporator and the water entering the side
of the tube or valve e is conveyed downward into the evaporator casing as feed
water. The fulcrum F2 which is adjustable, is between the float F and the valve
tube e the latter partly balancing the weight of the float. The fulcrum F2 of float
lever is made adjustable from outside the evaporator casing, by passing through
a stuffing box G to the screw threaded nut G¹, which is held in position by the two
armed bracket G. The upper end part of the fulcrum F2 is screw threaded, and
is flattened on two opposite faces where it passes through the bracket to prevent
turning, so that by moving the nut G¹ the fulcrum can be raised or lowered and
thus the level of the salt water inside the casing can be altered at will.
For the preventing of priming in the evaporator casing a short pipe or box H
is attached close under the vapour outlet orifice H¹ inside the evaporator casing,

page_text: the sides of pipe H being perforated at ¹ and top open and the bottom closed
but connected to a pipe 1 to drain any water accumulating in the bottom of first
mentioned pipe. Near the bottom of the top pipe is fitted sideways an inverted
conical plate J extending outwards to within a short distance of the
inside of evaporator shell A, the base of the conical plate J, being
upwards and the apex downwards, and a similar smaller conical
plate and paraller to the first is fitted higher up on the side of the top
pipe. This arrangement will prevent the water rising up and passing through
the vapour outlet H. The water thrown up by priming after passing the first
cone is directed downward by the bottom of the top cone J' through the holes h
in the side of large pipe H and it will then be drained downward and back to
an undisturbed part of the casing by the smaller pipe I fitted on bottom of large
top pipe or vessel. The vapour will pass freely round the bottom and top cone
plates JJ, and up through the holes at the top of pipe or vessel close to the
vapour outlet H.
Safety valves, gauge glasses and other mountings such as are common to all
types of evaporators are fitted as also a hand feed water inlet in a usual manner
as well as the automatic feed arrangement described.
In applying these improvements to act as a condenser, the steam tubes B would
be carried to near the top of vessel, and the baffle plates, and automatic regulating
gear be dispensed with while the outer vessel A would preferably be formed in
two parts and be bolted together at centre of height, while the top and bottom
tube sheaf covers 133 would be directly connected to the sides of outer shell of
condenser.
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:-
First. In evaporators, condensers, and the like for producing fresh water from
salt or impure water, the arrangement of sheaf of tubes with inlet and outlet
branches to enable the steam to be circulated uniformly throughout the evaporat-
ing tubes, substantially as herein described in reference to and shown in the
accompanying drawings.
Second. In evaporators, condensers, and the like for producing fresh water
from salt or impure water, the method of securing the ends of the tubes to the
tube plates substantially as herein described in reference to Figure 5 of the
accompanying drawings.
Third. In evaporators, condensers, and the like for producing fresh water
from salt or impure water, the automatic feed consisting of adjustable tube or
valve operated by a float lever, substantially as herein described in reference to
Figure 6 of the accompanying drawings.
Fourth. In evaporators, and the like for producing fresh water from salt or
impure water, the arrangement of cone plates and pipes for preventing priming,
substantially as herein described in reference to Figure 1 of the accompanying
drawings.
Fifth. The general arrangement in combination of the parts of evaporators,
condensers, and the like for producing fresh water from salt or impure water,
substantially as herein described in reference to and shown in the accompanying
drawings.
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.