Improvements in Multiple Effect Evaporating Apparatus for Evaporating or Concentrating Sugar Juice and other Liquids.
Year: 1889

page_text: Date of Application, 14th Aug., 1889
Complete Specification Left, 14th May, 1890-Accepted, 14th June, 1890
Improvements in Multiple Effect Evaporating Apparatus for
Evaporating or Concentrating Sugar Juice and other Liquids.
T. WILLIAM MAXWELL, of Djocdja, Java, Engineer, do hereby declare the nature
of this invention to be as follows:
In the class of apparatus to which my improvements relate, the sugar juice or other
liquid is evaporated under a pressure usually less than that of the atmosphere, the
heat being obtained in the first instance from steam which surrounds a number of
tubes through which the juice or other liquid circulates.
Each evaporator consists of an upper, middle and lower chamber; the upper and
lower chambers being connected by a number of tubes forming tubular heating
surfaces which pass through the middle or tube chamber.
In the ordinary construction of the evaporators, a central tube of considerable
diameter, termed a circulating tube, also commecis the upper and lower chambers,
passing through the middle chamber.
The juice or other liquid to be avaporated or concentrated enters the upper chamber
of the first evaporator, circulates down the circulating tube and up through the
tubular heating surfaces, being evaporated by the heat transmitted from the steam
which is admitied to the middle chamber and which condenses therein.
The upper chamber converges at the top to a suitable outlet and from this outlet
a connecting pipe leads to the middle or tube chamber of the second evaporator, so
that the vapour of the juice or other liquid evaporated in the first evaporator acts
as the heating medium to evaporate the juice or other liquid in the second, and so
on throughout the series, the upper chamber of the last evaporator being connected
with a condenser and air pump.
The water of condensation in the first evaporator is withdrawn through a steam
trap, and that in the other evaporators by means of a suitable withdrawing pump.
My improvements consist:-
First, in dispensing with the central circulating tube and substituting for it two
or more external circulating tubes which connect the upper and lower chambers
together and pass outside the middle or tube chamber; the space within the middle
chamber so obtained may be utilised for additional heating surface;
Second, in constructing the connecting pipe from the upper chamber of each
evaporator to the middle or tube chamber of the next so that the inlet to the latter
is deep in proportion to its breadth, and extends nearly the whole depth of the tube
chamber and Third, in so arranging the tubes in the tube chamber that passages are
formed between them, diverging from the inlet. thus allowing the vapour which
enters by this inlet to have free access to the external surface of all the tubes,
especially those at the side furthest from the inlet.
By constructing the connecting pipe and inlet and arranging the tubes in the
manner herein described, the heating medium or vapour readily reaches every part
of the heating surfaces, whereby the whole of these surfaces become practically
equally effective, while at the same time, the greater rapidity with which the heating
vapour is condensed, and the diminished resistance to its flow allow the evaporation
in the juice or other liquid from which it arises to go on under a lower pressure and
temperature than in apparatus of this class as usually constructed so that on the
whole of the efficiency is materially increased.
Dated this hay of Anerusi 1880
SLOAN & LLOYD BARNES,
26, Castle Street, Liverpool, Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Multiple Effect Evaporating Apparatus for
Evaporating or Concentrating Sugar Juice and other Liquids.
I, WILLIAM MAXWELL, of Djoedja, Java, 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:-
In the class of apparatus to which my improvements relate, the sugar juice or
other liquid is evaporated under a pressure usually less than that of the atmosphere,
the heat being obtained in the first instance from steam which surrounds a number
of tubes through which the juice or other liquid circulates.
Each evaporator consists of an upper, middle and lower chamber; the upper and
lower chambers being connected by a number of tubes forming tubular heating
surfaces which pass through the middle or tube chamber.
In the ordinary construction of the evaporators, a central tube of considerable
diameter, termed a circulating tube, also connects the upper and lower chambers,
passing through the middle chamber.
The juice or other liquid to be evaporated or concentrated enters the upper
chamber of the first evaporator, circulates down the circulating tube and up through
the tubular heating surfaces, being evaporated by the heat transmitted from the
steam which is admitted to the middle chamber and which condenses therein.
The upper chamber converges at the top to a suitable outlet and from this outlet
a connecting pipe leads to the middle or tube chamber of the second evaporator, so
that the vapour from the juice or other liquid evaporated in the first evaporator acts
as the heating medium to evaporate the juice or other liquid in the second, and so
on throughout the series, the upper chamber of the last evaporator being connected
with a condenser and air pump.
The water of condensation in the first evaporator is withdrawn through a steam
trap, and that in the other evaporators by means of a suitable withdrawing pump.
My improvements consist:-
First, in dispensing with the central circulating tube and substituting for it two
or more external circulating tubes which connect the upper and lower chambers
together and pass outside the middle or iube chamber: the space within the middle
chamber so obtained may be utilised for additional heating surface:
Second, in constructing the connecting pipe from the upper chamber of each
evaporator to the middle or tube chamber of the next so that the inlet to the latter
is deep in proportion to its breadth, and extends nearly the whole depth of the tube
chamber and Third, in so arranging the tubes in the fube chamber that passages
are formed between them, diverging from the inlet, thus allowing the vapour which
enters by this inlet to have free access to the external surface of all the tubes.
especially those at the side furthest from the inlet.
By constructing the connecting pipe and inlet and arranging the tubes in the
manner herein described, the heating medium or vapour readily reaches every part.
of the heating surfaces. whereby the whole of these surfaces become practically
equally effective, while at the same time. the greater rapidity with which the heating
vapour is condensed: and the diminished resistance to its flow allow the evaporation
in the juice or other liquid from which it arises to go on under a lower pressure and
temperature than in apparatus of this class as usually constructed so that on the
whole of the efficiency is materially increased.
In order that my invention may be readily understood. reference is made to the
accompanying drawings, in which my improvements are illustrated as applied to a
triple effect evaporating apparatus for concentrating sugar juice.
Fig. I is an elevation, the third evaporator 3 being in vertical section on the
line A. A of Fig. II: for the sake of greater clearness, the tubes 9 are removed.
Fig. II is a plan of the apparatus. Fig. III is a vertical section on either of the
lines of Fig. II, and Figs. IV and V are sectional plans on the lines CC
and D D respectively of Fig. III.

page_text: Only such details are shown as are necessary or useful to illustrate my present
invention 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 adjacent to the letters denoting the plane of section.
1, 2, and 3 are the first, second and third evaporators respectively, each divided
by the tube plates 4 and 5 into an upper chamber fi, a tube chamber 7 and a lower
chamber S. the tubes 9 connecting the chambers 6 and S.
10 are the external circulating tubes, three of which are shown. fitted on each
evaporator and connecting the chambers 6 and 8; one of these tubes is in each case,
by preference, placed opposite to the steam or vapour inlet; the others are as nearly
as possible placed equidistant round the circumference, but their position is
determined by the necessity of clearing the supporting frame-work 21 which is only
partially shown.
11 are the pipes for supplying the juice to be evaporated to the chambers 6.
The heating medium for the first evaporator, which enters the tube chamber thereof
and surrounds the tubes, is either exhaust steam admitted by the inlet pipe 12. or
boiler steam admitted by the inlet pipe 15. The vapour from the first evaporator
passes by the pipe 13 and inlet branch 14 to the tube chamber of the second
evaporator 13 and 14 are the corresponding pipe and inlet branch connecting the
second and third evaporators. As hereinbefore described, the inlets 16 to the tube
chambers extend nearly the whole depth thereof and so afford a very free passage for
the vapour.
The inlet branches 14 and 14' are sufficiently strong and firmly con-
nected to the shells of the tube chambers, so as to compensate for the weakening
effect of the large inlets 16, and a strengthening bar or tie 17 is preferably formed
across the mouth of each inlet branch.
18 are the outlet pipes for withdrawing condensed vapour from the tube chambers.
and 19 is the pipe leading the vapour away from the third evaporator to the
condenser.
The arrangement of the tubes is shown in Figs. IV and V. 20 are the diverging
passages hereinbefore referred to, left between the tubes for the purpose of affording
free access for the heating vapour to the external surfaces of the whole stack of
tubes; these passages may be arranged in any convenient way, and it is to be under-
stood that while I have shown them in conjunction with the external circulating
tubes 10, they may be used with advantage in conjunction with internal circulating
tubes of the ordinary kind.
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 multiple effect evaporating apparatus. the use of one or more circulating
tubes connecting the upper and lower chambers and passing outside the tube chamber,
substantially as described.
(2). In multiple effect evaporating apparatus, forming the vapour inlet branch and
opening to the tube chamber of the second and any succeeding evaporators of the
series substantially as described and illustrated.
(3). In multiple effect evaporating apparatus, arranging the tubes in the tube
chambers so as to form one or more passages between them leading from the vapour
inlet, substantially as described.
(4). In multiple effect evaporating apparatus, the combination of the deep inlet
opening 16 and the diverging passages 20, substantially as described and illustrated.
(5). In multiple effect evaporating apparatus, the combination of the deep inlet
opening 16, the diverging passages 20 and the external circulating tubes 10,
substantially as described and illustrated.
Dated this 13th day of Nov 1800
SLOAN & LLOYD BARNES,
26. Castle Street, Liverpool, Agents for the Applicant.