Year: 1897

page_text: Date of Application (in the United Kingdom), 17th Feb., 1897
Complete Specification Left, 4th Nov., 1897-Accepted, 8th Jan.,
1898
I, CHARLES BOURDON, of 26 Boulevard Magenta, Paris, France, Engineer do
hereby declare the nature of this invention to be as follows:-
This Invention relates to apparatus to which I have given the name of ejector-
condenser for effecting the condensation of steam in engines and receivers in which
a certain degree of vacuum is to be maintained by the aid of apparatus independent
of the engine, and for reducing to a certain extent the expenditure of water required
for this accessory service.
The ejector-condenser also has the further advantage of being composed of simple
parts capable of being put in action at any moment even although they may have
remained for a long time out of use. The use of condensers of the injector type
are sufficiently well known. In these apparatus the vacuum produced by the
condensation of the steam in contact with water, causes the water to arrive at a
high velocity in the bi-conical nozzle which forms the condenser, in such manner
that the passage of this liquid vein produces an intense suction at the summit of
the cones which draws in the air. Thus the vacuum is maintained in the capacity
in which it is required to be produced, just as by an air pump. These apparatus
work well but they necessitate a large expenditure of water and often of steam
taken directly from the boiler, as without this addition of steam under pressure,
the velocity of the liquid vein would not always be sufficient to obtain a normal
vacuum. It is to be observed that this additional injection of steam has the disad-
vantage of heating the water and is also rendered greater owing to the fact that a
bi-conical nozzle is used, which is an apparatus of very low efficiency.
The essential feature of my ejector-condenser consists as in the apparatus above
referred to of a bi-conical nozzle but in the combination which I have devised, I
separate so to speak the two operations of suction of air and condensation.
For the first operation I make the water serve for producing a mechanical effect,
so that it may without inconvenience be used hot, while for the second operation
I employ cold water which may be of relatively small volume as it is only required
to condense that which the hot water has failed to do.
The suction of air is produced as in the apparatus previously referred to by the
passage of a liquid vein through a bi-conical nozzle, but at such velocity as is
necessary for producing the required vacuum, imparted to it by mechanical means
such as a centrifugal pump which acts with much greater efficiency than apparatus

page_text: conducted into the suction chamber as shown in Figures 1 and 2 or as in the
arrangement illustrated in Figure 4, into the extremity of the convergent cone A
by means of the bent pipe Q. In the latter case the communication R with the
suction chamber may remain open in order that the ejector A, B may absorb all
the steam which it can take by reason of the temperature to which the water
passing through it is raised, the second ejector serving merely to condense the
excess steam and to complete the vacuum.
A modification of the above described arrangements which would permit of
reducing to a minimum the expenditure of water consists in leading the steam
which may leave the cylinder of the engine during the initial period of the exhaust
directly to the ejector that is to say into the chamber C. As at this moment a
vacuum is not required in the cylinder, the water circulating in the ejector may
without inconvenience be allowed to attain a very high temperature, 80° C. for
example. The cold water in this case would be introduced at the second bi-conical
ejector, but it would only be required to condense the steam escaping from the
cylinder during the period of exhaust proper, and the weight of which would be
considerably reduced owing to the partial vacuum produced by the first absorption.
To carry out this mode of working it is necessary to place on the cylinder two
special valves which would be operated by the movement of the piston and would
remain open during the first period of the exhaust, whilst the ordinary distributing
apparatus would establish the communication between the cylinder and condenser
only during the period of exhaust proper. This mode of working may be employed
with ordinary condensers provided with air pumps, if it be desired to utilize the
water to better advantage and reduce its expenditure. Two condensers and two air
pumps coupled together and acting on what may be termed a compound system,
would suffice. One of the two groups would be in communication with the
cylinder during the exhaust proper and would receive cold water. The second
would condense like the ejector and ejector-condenser, a considerable portion of the
steam during the first period of the exhaust, at which moment it would be made
to communicate with the cylinder by means of special distributing apparatus, the
condensation in the second condenser being effected by the water delivered by the
air pump from the first one, that is to say with water at 35° to 40° C, and
the temperature of which may by this second utilization be raised to 55° or 60°
without impairing the vacuum of the condenser proper which is put in communi-
cation with the cylinder during the exhaust. This compound condensation would
thus considerably diminish the expenditure of water and present advantages when
as it often happens only a limited quantity is available.
This apparatus by reason of the property which it possesses of reducing in a
considerable proportion the expenditure of water, permits of effecting condensation
under entirely novel conditions. At present when surface condensation is employed
the steam on leaving the cylinder enters a receiver containing an assemblage of
tubes of considerable extent which is kept constantly cooled by a circulation of
water. The cost of construction of these tubular condensers, which are composed
chiefly of copper, is considerable and the tube joints require to be very carefully
made by costly methods in order to ensure their being perfectly tight and prevent
any entry of the circulating water into the condenser notwithstanding the vacuum
which exists in the apparatus.
Moreover the receiver which contains the assemblage of tubes and which is
consequently of considerable size, requires to have very thick walls in order to resist
the atmospheric pressure, and its weight is therefore considerable.
In the ejector-condenser as the water discharged at the overflow is of a high
enough temperature to induce a rapid transmission of heat and is much less in
volume than that required for condensing by jet in the ordinary way, it can be
readily cooled in any kind of refrigerator. It is not a question of maintaining a
vacuum in this apparatus which is completely filled with water and there is no fear
of leakages as there is no. difference of pressure between the currents of water to
be cooled and of that used for cooling. The construction of the refrigerator is

page_text: such as a centrifugal pump which acts with much greater efficiency than apparatus
directly utilizing the vis viva of steam. In order to reduce as much as possible
the expenditure of motive power required for forcing the water through the bi-
conical nozzle I arrange the apparatus in such manner that the pump employed
for this purpose has, so to speak, merely to maintain a continuous circulation of
the same liquid mass in a closed circuit.
Notwithstanding this mode of working however, it is not the same water which
circulates indefinitely in the apparatus, as the increased temperature which it
acquires would quickly render any absorption of steam impossible. A certain
quantity of cold water is introduced continually into the condenser, either by means
of a rose or bi-conical nozzle of smaller dimensions than that used for suction. This
additional water which is continually added to that which may be contained in the
closed circuit formed by the apparatus, is discharged with the aspirated air by an
overflow pipe at a certain height in the suction chamber of the pump. In this
manner the water which circulates in the suction tube is utilized as above men-
tioned in the first place for absorbing as much steam as is permitted by the
temperature which it is allowed to acquire after the addition of more or less cold
water while on the other hand it furnishes by its passage through the bi-conical
nozzle, the mechanical work needed for the aspiration of the air and water con-
tained in the condenser. This liquid vein which traverses the ejector constitutes,
so to speak, a continuous liquid valve which intercepts communication between
the atmosphere and the condenser; as above mentioned this mechanical work of
absorption is effected within certain limits as well with hot as with cold water so
that the temperature of the continuously circulating volume may be allowed to rise
more or less according to the vacuum which it is desired to obtain but in all cases
the water which is discharged at the overflow and which is equal in volume to the
additional fresh water supplied will be much hotter than that which would be
employed in a condenser of the ordinary kind. By this means much less water may
be expended to effect condensation.
Figures 1, 2, 3, and 4 of the drawings accompanying my Provisional Specification
illustrate in detail the different arrangements which may be adopted for the con-
struction of the ejector-condenser.
DESCRIPTION OF THE EJECTOR-CONDENSER.
Figures 1, 2, and 3 illustrate the general arrangement of the apparatus which
comprises as its essential feature a bi-conical nozzle A B of the proportions best
suited for the purpose. The annular space between the cones which form the
nozzle is enclosed in a casing C which forms a suction chamber and the other
extremities of the cones are extended in the form of bent tubes DD¹ respectively
connecting with the suction and delivery pipes E and F of a centrifugal pump G
driven by a belt or dynamo. The suction pipe is surmounted by a tank H which
is open, to the upper part of which is attached an overflow pipe I. Upon the
suction chamber C is fixed the condenser consisting of a chamber K to the upper
part of which, as in Figures 1 and 2, or laterally, as in Figure 4, is connected a
water inlet pipe L, the steam to be condensed being admitted to the condenser
by a pipe M. The water may be injected through a sprinkler N (Figure 6) or by
means of a bi-conical aspirator 0 arranged as shewn in Figures 1 and 4 and drawn
half the full size in Figure 5. This nozzle when of the ordinary proportions will
exhaust the steam and air contained in the condenser first through the space a
and then through a series of orifices 6 provided along the divergent cone in which
the direction of the steam and air aspirated is determined by a series of conical
rings fitting upon the conical tube which should be as thin as possible. The suction
produced by the bi-conical nozzle AB determines a very rapid passage of the
water through the second ejector which absorbs the steam through the series of
orifices throughout almost the entire length of the divergent cone. The admis-
sion of water thereto is regulated by a valve, the stem of which is prolonged in the
form of a tapering shank P whereby the injection of water may be diminished
without causing any loss of charge. The water in its exit from the cone may be

page_text: therefore exceedingly simple even if formed of a receiver containing an
assemblage of tubes through which cold water is passed, the hot and cold currents
circulating methodically in reverse directions. The sides of such a receiver may be
thin and it may be of relatively light construction. Moreover as the tube joints
are not subject to strains either by the vacuum or the effect of expansion, the most
simple and economical construction may be employed for the circulating tubes.
However, in consequence of the difference which exists between the co-efficients
of transmission from water to water and from steam to water, the surface of the
refrigerator would be greater than that of an ordinary surface condenser notwith-
standing the reduction in the volume of the condensing water due to the use of the
ejector-condenser.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed, I declare that what
I claim is:
1. The herein described method of condensing steam by means of an apparatus
consisting essentially of a bi-conical aspirator through which a continuous circula-
tion of water is maintained at a high velocity whereby the aspirator is caused to
act as an air pump, the condensation (which may be effected by the so-called
compound method) being completed by an injection of cold water by means of a
sprinkler or ejector of smaller dimensions provided or not with a series of conical
rings.
2. The employment of the herein described ejector-condenser in combination
with a tubular refrigerator for cooling the water discharged at the overflow substan-
tially as specified.
Dated this 4th day of November 1897
A. M. & WM. CLARK,
Chartered Patent Agents, 53 Chancery Lane, London.