Improvements in and relating to Evaporating Apparatus.
Year: 1890

page_text: Date of Application, 12th Mar., 1890
Complete Specification Left, 3rd- Dec., 1890-Accepted, 24th Jan., 1891
PROVISIONAL SPECIFICATION.
Improvements in and relating to Evaporating Apparatus.
I, ROBERT HARVEY, of the firm of McOuic, Harvey, & Company, Engineers,
Scotland Street, Glasgow, Lanarkshire, do hereby declare the nature of my invention
to be as follows:-
This invention has reference to and comprises improvements in the construction,
or arrangement and combination of the parts, of vacuum evaporating apparatus,
specially applicable to that known as triple or multiple effects of the character in
which the evaporating and heating vessels are placed vertically side by side, and in
which the liquor or juice to be evaporated is passed through vértical tubes secured
at their open ends through the two end tube plates of a close steam or vapour heating
vessel or calandria placed or fitted at the lower part of the evaporating vessel, with
a return liquid space at the lower end of the vessel, and in which the steam or
vapour is drawn off from the top of the liquid vessel, above the heating vessel to
the next evaporator in the series, and to the vacuum condenser from the last vessel,
all so as to boil under vacuo in the several vessels, the vacuum being greatest in the
vessels nearest the condenser. The new improvements are for the purpose of giving
a greater circulation and evaporation of the liquids under treatment in, and generally
to simplify the construction of such evaporators.
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The nature and novelty of the improvements consist as follows:-First, in the
admission of the "live or exhaust heating steam, or the vapour from the preceding
vessels, to the lower or to the upper part or both of the close tubular heater of each
evaporator, from the large circular pipe or branch, by tapering branches or ducts
contracting in height or depth, but widening out at a tangent towards the outer
part of the shell of the heater, that is, widening in the reverse direction towards the
heater that it contracts in the vertical direction, so that the steam or vapour enters
the lower or upper parts of the heating vessel in a strong narrowing stream in the
vertical section, but widening out fanways to the full width of the vessel and tubes to
be heated in sectional plan, thus distributing the heat over the whole surface of the
front tubes exposed to it. These widening or contracting ducts or branches, which
I term the inlet steam heating branches, would preferably be partly formed in one
with the heating vessel, and partly on a separate branch between this and the steam
or vapour pipe, and have sluice or other valves fitted in these branches.
When two,
three, or more of these evaporators are used, as a duplex, triple, or multiple effect,
the vapour from the top of each vessel would be led off by a lateral bend to a separate
vessel fitted round the upper open end of a single stand vapour pipe, forming also
a liquid trap at top and leading the vapour down to the upper end of the improved
heating steam branch or branches before mentioned, a small tube being led from
the bottom of the save-all trap above into the top of the evaporating vessel, the
upper part of the trap of the last evaporator leading direct to the vacuum condenser,
flanged joints generally being preferred on these new heating steam branches and
the trap branches for the ease and accuracy of making tight vacuum joints, and
these vertical vapour pipes between the evaporators night either be placed in
vertical line or plane with them, or laterally to one side, and so be able to place
the evaporators close together.
A further improvement consists in the use of an intercepting vertical deflecting
plate or plates between the rows of tubes, transversely to the said inlet heating
steam branches or ducts. The first deflecting plate would be erected through the
tubes towards the centre and a considerable distance above the bottom tube plate or
below the top tube plate, so as to divert the heating steam or vapour upwards or
downwards from where it entered parallel to the tubes between these plates and the

page_text: heating steam branches, leaving space between the deflecting plates, or between these
and the tube plates, for the vapour to pass on and act on all the other tubes, where
another deflecting vertical plate or plates might he intercepted to cause the heating
vapour to descend or ascend around the last sets of heating tubes at the opposite
side of the cater to where the heating steam or vapour entered, the tubes of which
would therefore be much colder than the tubes on the side where the steam entered ;
and where a large vertical tube or pipe would preferably be fitted between the tube
plates for the liquid to descend through this and through the other small tubes on
this colder side of the heater, and ascend up through the whole of the tubes on the
hot side of the heater. A vertical opening would preferably be formed between the
upper and lower flanges of the heating chamber, with screwed-on closing lid or cover
outside for the removal and shifting of the vertical deflecting plates between the tubes
to the best effective position, notches or other equivalent being formed inside the
shell for retaining the deflecting plates in true central position Letween the heating
tubes. The juice or liquor to be treated would be supplied by a lateral branch or
bend from the pumps or from the bottom end of a preceding evaporator, so as to
descend and assist the current of the liquid down the large tube on this cold side of
the tubes and heater. The deflecting plate or plates would have small holes at their
lower part to allow the condensed water to pass along the lower tube plate to the
cold side of the heater, where it would be drawn off by a branch to the inlet heating
steam branch of the next evaporator. This branch would be fitted with a valve or
cock, and be large enough not only to draw off all the condensed water, but sufficient
of the steam or vapour to assist the flow of the condensed water and also_the_onward-
current of the heating vapour-of-the one evaporator-into-the-heating vessel of the
next; and by special branches or tubes from the upper part of their heating vessels
draw off all ammonia or other gases from these outwards through the several
heating vessels, from the last of which they would be drawn off by traps or pumps
or other ordinary means heretofore employed for that purpose.
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COMPLETE SPECIFICATION.
Improvements in and relating to Evaporating Apparatus.
I, ROBERT HARVEY, of the firm of M*Onie Harvey & Company, Engineers, Scotland
Street, Glasgow, Lanarkshire, 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, reference being had to the
accompanying sheet of drawings and to the letters and figures marked thereon, that
is to say :-
My invention has reference to and comprises improvements in the construction and
arrangement and combination of the parts of vacuum evaporating apparatus, specially
applicable to that known as triple or multiple effects of the character in which the
evaporating and heating vessels are placed vertically side by side, and in which the
sugar juice or other liquor to be evaporated is passed through vertical tubes secured at
their open ends through the two end tube plates of a close steam or vapour heating
vessel or
"calandria" placed or fitted at the lower part of the evaporating vessel, with
a return liquid space at the lower end of the vessel, and in which the steam or vapour
from the liquor is drawn off from the top of the liquid vessel above the heating vessel
to the heating chamber of the next evaporator in the series, and to the vacuum
condenser from the last vessel, all so as to boil under vacuo in- the several vessels, the
vacuum being greatest in the vessels nearest the condenser. The new improvements are
for the purpose of giving a greater circulation and evaporation of the liquids under
treatment in, and generally to simplify the construction of such evaporators.
And in order that my said invention and the manner of performing or carrying the
same into effect or practice may be properly understood I have hereunto appended an

page_text: explanatory Sheet
corresponding parts in all the figures where shown.
Figure 1 is a vertical sectional elevation of one evaporating vessel, of a set of
multiple effects showing my improvements applied thereto.
Figure 2 is a horizontal section through the steam or vapour inlet pipes and valves
and heating vessel, as taken on the line 1-1 of Figure 1, and
Figure 3 is a horizontal section broken away of the ports leading the heating vapour
to the next or succee ling evaporating vessel of the triple or multiple effects as taken
on a line such as 2-2 in Figure 1.
Referring to these drawings, the improvements consist, as follows.-First, in the
admission of the "live" or exhaust heating steam to the tubular heating chamber A
near the lower part of the evaporating vessel B, B', from the double branch pipe C
or the vapour from the preceding vessels when two or more vessels are used working
in series, to the lower or to the upper part or both of the close tubular heater A A of
each succeeding evaporator, from the large circular stand pipe or branch D D', by
wide and tapering branches or ducts A' A" contracting in height or depth at C Du,
but widening out at a tangent at A" towards the outer part of the shell A of the
heater, that is, widening in the reverse direction towards the heater that it contracts
in the vertical direction, so that the steam or vapour enters the lower or upper parts
of the heating vessel A in a strong narrowing stream in the vertical section, but
widening out fan ways to the full width of the vessel and tubes to be heated, as seen
particularly in sectional plan in Figures 2 and 3, thus distributing the heat over the
whole surface of the front tubes a exposed to it. These widening or contracting ducts
or branches A¹ A", which I term the inlet steam and vapour heating branches, are
preferably partly formed in one at A", with the heating vessel A, and partly on a
separate double branched_pipe C C C and D D" respectively between this and the
steam or vapour pipe C D, and preferably have sluice or other valve chests (² (2
and D2 D2 fitted in these branches (", ", to regulate and admit any desired quantity
of steam or vapour through the upper or lower expanding ducts A A" to the heating
vessel A, the valves c of each chest C2 C2, and D2 D2 being actuated by two screws
and screw wheels and screw spindles outside the chests c", c, or other equivalent
arrangements of valves and gearing. The steam or vapour heating vessel is constructed
of a large outer cylindrical vessel A formed with flanges at its upper and lower
ends A, and with upper and lower end tube plates A2 A³ into which the heating
tubes a are expanded or secured with intermediate tie bolts a', these end tube
plates A2 A3 being secured between the flanges A and the lower flanges B of the
upper vessel B, and the flanges B of the lower end vessel B', all so that the liquid
circulates up these tubes and down through a large tube a, all as indicated by the
arrows in Figure 1. When two, three, or more of these evaporators B B', are used,
as a duplex, triple, or multiple effect, the vapour from the top of each vessel B B', is
led off by a lateral bend pipe or branch B to a separate vessel B fitted round the
upper open end of the stand vapour pipe D, the vessel B forming also a liquid trap
at top, and leading the vapour down to the improved duplex heating vapour
branch D, D. "D", before mentioned. The trapping vessel B³ is either made as
shown to lead the trapped liquid back to the liquid vessel B or a tube might be led
from the bottom of this save-all trap B³ into the upper part of the ovaporating vessel B,
the upper part of the trap of the last evaporator leading direct to the vacuum
condenser. Flanged joints are generally preferred on these new heating steam
branches C D and A' A", and on the upper and trap branches B³ B³ for the ease
and accuracy of making tight vacuum joints, and these vertical vapour pipes D D',
between the evaporators B B, night either be placed in vertical line or plane with
them, or laterally to one side, and be able to place the evaporators B B₁ closer together.
A further improvement consists in the use of an intercepting vertical deflecting
plate E, between the rows of tubes a transversely to the said inlet heating steam
branches or ducts A' A", preferably as shown in Figure 1 nearly in the centre of the
vessel A. This deflecting plate E may be inserted up through a slot e in the tube
plate A covered in by a Hange or cover plate E' screwed to the plate A³ on both

page_text: sides of the slot e, so as to divert the heating steam or vapour upwards or downwards
from where it entered parallel to the tubes a leaving space as at E' between the
deflecting plate E and the end tube plates A2, A3, for the vapour to pass on and act on
all the other tubes a beyond the deflecting plate E, to cause the heating vapour to
descend or ascend around the last sets of heating tubes at the opposite side of the
.heater to where the heating steam or vapour entered, the tubes of which would there-
fore be much colder than the tubes on the side where the steam entered; and where
a large vertical tube or pipe a' is preferably fitted between the tube plates A2 A3 for
the liquid to descend through this and through the other small tubes a on this colder
side of the heater, and ascend up through the whole of the tubes a on the hotter side
of the heater. Suitable grooves at are cast or formed inside the shell A for
retaining the deflecting plates E, in true central position between the heating tubes a
in line with the slot e. The juice or liquor to be treated is supplied by a lateral
branch or bend from the pumps or from the bottom end of a preceding evaporator
and led into the top of the tube a², so as to descend and assist the current of the liquid
down the large tube a² on the cold side of the tubes and heater as indicated in dotted
lines at F. In some cases two or more of these deflecting plates E may be inserted
between the tubes a at considerable distances apart as described in reference to the
single plate E, with the openings at different parts in them, to cause the steam to
be deflected in opposite directions between the successive plates to act more effectively
on the tubes in the spaces between them. The deflecting plate or plates E-may have
small holes at their lower part to allow the condensed water to pass along the lower
tube-plate-A to the cold side of the heater, where it would be drawn off by a branch
at A to the inlet heating steam branch of the next evaporator or to a trap by the
branch A. The branch A may be fitted with a valve or cock, and be large enough
not only to draw off all the condensed water, but sufficient of the steam or vapour-to
assist the flow of the condensed water and also the onward current of the heating
vapour of the one evaporator into the heating vessel of the next; and by special
branches or tubes from the upper part of their heating vessels draw off all ammonia
or other gases from these outwards through the several heating vessels, from the last
of which they would be drawn off by traps or pumps or other ordinary means
heretofore employed for that purpose.
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 and use of single, double, triple, or multiple effect,
evaporating vessels for sugar juice and other liquors with duplex expanding branches
or ducts which lead the steam or vapour from a single branch or duct to the upper
and lower parts and to the full size of the tubular beating vessel or vessels, sub-
stantially as and in the manner herein described in reference to and shown in the
accompanying drawings.
Second. In single, double, triple, or multiple effect evaporating vessels, for sugar
juice and other liquors, the construction and use of duplex expanding steam or vapour
inlet branches in the tubular heating vessel or vessels, in combination with one or
more intercepting vapour vertical deflecting plates within the tubular vessel or vessels,
substantially as and for the purposes herein described in reference to and shown in the
accompanying drawings.
Third. In single, double, triple or multiple effect evaporating vessels for sugar
juice and other liquors, the fitting and use of sluice or other valves on both the upper
and lower branches or ducts of the tubular steam or vapour heating vessel, sub-
stantially as and for the purposes herein described in reference to and shown in the
accompanying drawings.