Improvements relating to the Condensation of Steam or Vapour and to Apparatus therefor.
Year: 1892

page_text: Date of Application, 17th Sept., 1892-Accepted, 3rd Dec., 1892
COMPLETE SPECIFICATION.
Communicated from abroad by SANGERHÄUSER ACTIEN-MASCHINENFABRIK
UND EISENGIESSEREI, vorm. Hornung and Rabe, of Sangerhausen, in the
Empire of Germany, and F. J. WEISS, of Basle, in the Republic of
Switzerland.
Improvements relating to the Condensation of Steam or Vapour and
to Apparatus therefor.
1. WILLIAM ROBERT LAKE of the firm of Haseltine Lake & Co., Patent
Agents, 45 Southampton Buildings, London, W.C. 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 :-
This invention relates to the condensation of steam and other vapours and to
apparatus therefor. It has for its object to obviate a defect which is associated
with the use of counter current condensers, and occurs whenever they operate
with the greatest efficiency and therefore under the most favourable conditions.
The terms "counter current condensation" and " parallel current condensation "
are dealt with in an article on "Condensation in the Journal of the Society of
German Engineers 1888, page 9, and are also explained in Grashof's "Theoretische
Maschinenlehre," volume 111, page 668.
"
If in a condenser a certain weight of steam, coming from a steam engine, an
evaporating apparatus or the like, is mixed with a certain weight of water of a
certain temperature the liquid mixture possesses a definite temperature which is
always the same whatever may be the system on which the condenser is arranged.
In case however the apparatus is a counter-current condenser the pressure prevailing
therein may be completely lowered by an air pump of finite size to the pressure
of saturated vapours corresponding to the temperature of the liquid mixture (the
hot water running off), whereas that is physically impossible in the case of a
66 wet air-
parallel current condenser, and likewise with any condenser having a
pump, or could only be attained with an infinitely large air-pump. The state in
counter-current condensation, in which the vacuum has been completely raised to
that which corresponds to the temperature of the hot water running off, and where
therefore the condensation performs its maximum duty or works with a degree of
efficiency of 100 per cent. is hereinafter called the "ideal point."
"
Experience has shown that with properly arranged counter current condensers
the said ideal point is easily attainable at any time and is actually attained. But
when such is the case the remarkable phenomenon occurs that the water in the
condenser rises and enters the air suction pipe terminating in the same at the top.
If between the condenser body and the air pump, which with counter current
condensation must always be a "dry" one, no so-called water separator is included
the water passes over into the dry air pump in enormous quantities, so that the air
cylinder is completely filled thereby; and as this pump in the nature of things is
not arranged for the delivery of water, serious disturbances in the working, if not
the destruction of the air-pump, are the immediate consequence. In case however
a water separator I, Figs. 1 and 2, is employed, which must be placed sufficiently
high for the water, which passes over into it and is separated from it, to be auto-
matically carried off by a water barometer pipe I' and if this water barometer pipe
or waste pipe 1' is wide enough for carrying off all the water which has passed
over, no water will pass into the air pump. It has then been found that as soon
as the ideal point is reached or perhaps even somewhat exceeded and water there-
fore passes over, the entire quantity of water conducted to the condeuser passes
over into the water separator 1, not a drop of water passing through the waste
pipe proper. The steam condenses in the pipe E on its way from the counter

page_text: "
current condenser C to the water separator I, which it traverses together with the
water (or "parallel to it); in other words when reaching the ideal point the
(counter current) condensation shifts from the (counter current) condenser body
proper C to the water separator I, Fig. 2, and thus becomes a parallel current
condensation. Accordingly the waste pipe I' from the water separator I (or, more
correctly, from the parallel current condenser body I) must be made of such
width that with the available height of water it is capable of carrying off all
the condensed water; then the air-pump L is protected in all cases against access
of water.
It has further been found that, if once the passage of the water to I has
commenced and the condensation has changed from a counter current conden-
sation to a parallel current condensation, this state will never cease of itself, but
will continue until the condensation is stopped.
From this results the following inconvenience, that is to say, as under otherwise
similar circumstances (equal quantity of the stear to be condensed, equal quantity
of the cooling water, equal temperature of the cooling, water, equal capacity of the
air pump) a lower vacuum is always produced with a parallel current than with a
counter current, the vacuum sinks in the condenser during the state just explained,
where the condensation takes place by parallel current; it is therefore desirable
to bring this state, if it has occurred, rapidly to a termination and to shift the
condensation back again to the condenser body proper C, where it takes place again
by counter current, without any necessity for stopping the condensation.
Now it has been found that this may be accomplished either by putting the
steam pipe B for a moment in direct communication with the air suction pipe 'E,
Fig. 2 or by allowing for a moment some air to pass into the space of the condenser,
in which the air has been rarefied, or into the spaces or pipes in connection
therewith.
If either of these means is used at once, as soon as the running of water through
the parallel current body I has began, the condensation is then shifted back in a
sure manner into the counter current body C, whilst this acts with less certainty if
the said state has been allowed to last for some time and these means are not used
until later on.
These means are in the following manner rendered automatic and immediately
operative as soon as the running of water through I begins.
The water barometer waste pipe I' is arranged so as to terminate in a basin or
vessel 12, Fig. 1, which has a lateral outlet a little above the surface z, z of the hot
water running off; the exhaust steam pipe B is connected with the air suction
pipe E through a pipe a b having the cock e inserted, which is usually kept closed
by the counterweight attached at f to the lever fcd for actuating the cock; from
the other end d of this lever is suspended a pail g in such a manner that water must
run into it as soon as the vessel 12 runs over; the pail y has at its bottom an
opening which always remains open.
condensation shifts from C to I, so that the whole volume of water runs off*
As soon as the ideal point is reached and the
through I, the pail g becomes filled (despite its having an opening below, because
the latter is too small for the entire volume of water which passes over to prevent
the immediate emptying of the pail) the weight of the volume of water filling it
overcomes the counterweight f, turns the said lever to the position f¹ d¹ and opens
the cock c, Fig. 2, whereby, owing to equalization of pressure taking place
between B and E, the condensation is at once shifted back to C again, and the
running of water through I and 1' ceases, the pail g therefore no longer contains
water; it is now emptied at once through the opening below, which always remains
open, and the counterweight f closes the cock c again, Fig. 1. This state lasts
until the ideal point is reached the next time whereupon the same operation
recommences; longer and longer periods; during which the condensation takes
place by the counter-current which acts under favourable conditions, alternate with
very short periods during which the condensation takes place by the parallel current
which acts under less favourable circumstances.

page_text: In the arrangements illustrated in Figs. 3 and 4 the descending pail g opens the
cock c and allows air to pass into the air suction pipe E. (Fig. 3) or into the
steam pipe B (Fig. 4), if the water comes down through the pipe I. By reason
of the vacuum which momentarily sinks a little owing to the admission of air the
condensation immediately shifts from the body I back again to the body C, the
water discontinues to pass through I and I', the pail g is emptied, and the cock c is
closed again, as herein before described with reference to Figs. 1 and:2.
Of course in lieu of the cock c shown, use may be made of any other closing
device c, for instance a lift valve, slide valve, or the like, which is opened by the
descending pail and then closed again by a counterweight or by an equivalent
spring.
The water barometer column in the waste pipe A, Fig. 1, is liable to fluctuate
vertically, as is also the case with the column of mercury in an ordinary barometer
which column fluctuates considerably if the barometer is moved but very little.
There are many causes for such fluctuations for instance the air pump takes its
air from the condenser by starts, and it is by starts that the steam comes into the
condenser when the latter is used in connection with steam engines.
If by chance the intervals between these steam and air jerks are in a simple
ratio to the period of fluctuation of the waste water column, their effects are added
These also occur directly
together and occasion the greatest fluctuations of water.
if the condenser is used for large steam engines which are loaded very unequally,
for example engines for driving rolling machines, where the cut-off changes very
considerably, so that often enormous volumes of steam, pass suddenly into the con-
denser, thereby producing of course violent jerks, whilst immediately before the
volume of steam admitted was perhaps very slight. If in the case of such
fluctuations of water the surface of the water -y rises in the waste pipe A into
the condenser and above the point where the steam pipe B terminates in the
condenser, water would then flow back into the exhaust steam pipe B, which
when the condenser is in connection with steam engines, would have the most
serious consequences.
The fluctuations of the waste water column are obviated in an extremely simple
and certain manner by simply providing a flap valve K at the lower end of the
waste pipe. When fluctuations take place downwards the flap valve allows water
to pass out; but at the moment when the fluctuation tends upwards the flap valve
closes, thus preventing this fluctuation upwards, and therefore also the next
fluctuation downwards, which the former would have caused. The surface .r of
the water remains tranquil. The return flow of waste water into the exhaust steam
pipe B which would otherwise have to be feared, is then also obviated, without
requiring the condenser to be placed at more than the water barometer height
(10.3 metres) above the low-water level, i. Such vertical fluctuations of water
may also occur in the other waste water column 1', although they are not so
serious as those in A, inasmuch as they would have to be very great for water to
reach even up to the very elevated point where the pipe E terminates in the
body I, these fluctuations of water in the pipe I are also obviated by providing a
flap valve K2 at its lower end in the same manner as represented at the lower end
of the pipe A.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed as communicated to me by
my foreign correspondents I declare that what I claim is ;-
First A method of condensing steam and other vapours by counter-currents
alternating with parallel currents, in which the condensation effected at intervals
by the parallel currents is brought back to condensation by counter currents,
substantially in the manner described and for the purpose specified.
-
Second An apparatus for condensing steam and other vapours, in which the
water running off through the parallel current body or water separator I, fills a
paily, and causes it to sink, thereby opening a closing device c which either brings

page_text: the steam to be condensed directly in communication with the air suction pipe
leading to the air pump, or allows air to pass into the spaces, in which the air has
been rarefied, of the condenser or of the pipes connected with the latter, for the
purpose specified.
Third-The arrangement of return flap valves K and K² at the lower end of
the barometric waste pipes A and 1', for the purpose of preventing fluctuations of
the columns of water upwards and therefore the running over of the water to the
pipes B and E.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.