Method of Utilizing the Latent Heat of Exhaust-steam.
Year: 1888

page_text: Date of Application, 6th Sept., 1888
Complete Specification Left, 29th May, 1889-Accepted, 29th June, 1889
PROVISIONAL SPECIFICATION.
Method of Utilizing the Latent Heat of Exhaust-steam.
I, WILHELM SCHMIDT of Halberstadt, S Plantagenstrasse, Germany, civil engineer
do hereby declare the nature of this invention to be as follows:-
My invention consists in a method of utilizing the latent heat of exhaust steam.
With the steam-engines known up to the present the exhaust-steam, that is to say
its latent heat is utilized only to a very small extent through condensation, heating
the feed-water etc. the greater part of this latent warmth is however lost.
The purpose of the method described below and illustrated in figs. 1-7 of the
drawings, is to arrive at a better utilisation of this steam, containing latent heat.
'
The proceeding essentially consists in first making the working-steam act in a
steam-engine and by it, compressing air & in conducting the exhaust-steam of this
engine into an indirect acting vaporizing apparatus through which the compressed air
passes, and whereby this air is made to absorb fluid in the shape of steam. The fluid
evaporates at the vaporizing surfaces, which are heated by the exhaust-steam. Thus
it is possible that the vaporized fluid, which naturally takes the tension of the com-
pressed air, increases the quantity of the compressed air-volume, the tension thus
increased may be used in any manner whatever in other engines.
From the above it is clear, that the increase of quantity has been obtained in
utilizing the latent heat of the exhaust-steam.
Fig. 1 represents a simple arrangement of this method.
A is the steam-cylinder in which the live-steam is expanded from 6 atmospheres to.
1 atmosphere.
B is the air compressing-cylinder, in which air is compressed from 1 to about
6 atmospheres. The exhaust-steam escapes from the two pipes and through the
pipe into the chamber 13 from where it fills the heating-tubes . From the pipes
water flows over these heating-tubes & which flows along their surface and which in
streaming down, is evaporated by the heated tubes 1, this evaporated fluid is met by
the air compressed to atmospheres & which flows from the air pump B through
pipe and absorbs the evaporated volume and the result is a mixture of compressed
air & steam of the same tension as the compressed air. This mixture of air and steam
escapes through the pipes R and may be used at pleasure in motors. It must be
pointed out that through the admixture of air this working-volume suffers very little
loss trough condensation in the conduit-pipes and that this mixture, therefore, is
specially suitable for separate motors far apart from each other.
The exhaust-steam in the box 13 and in the tubes will be condensed in consequence
of the action of the water from and the water resulting, will gather in the box 13,
from whence it is led into the pipes by a mechanical contrivance and used for
passing over the heating-tubes *. All of the steam is not condensed, part of it is
be allowed to escape from the box 13, which is suitably supplied with a discharge-valve,
so that the tension in this box can be kept at one atmosphere.
The arrangement as represented in Fig. 2 serves to arrive at a more perfect.
utilisation of the exhaust-steam, respectively the latent heat of the same, in this
case the proceeding is a gradual one, working with exhaust-steam of increasing.
tensions.
The two steam-cylinders a¹, a work with different expansions so, that on the back.
side of the piston in a' there is an expansion from 6 to 1 atmosphere, on the other
side an expansion from 6 to 1, 5 atmosphere, and on the back side of the piston
In a an expansion from 6 to 2, 5 atmosphere, and on the other from 6 to 2
atmospheres.
The exhaust-steam of different tensions thus obtained, which also posses different

page_text: temperatures of 100°, 110°, 120° respectively 127° is conducted through the tubes s',
52, 3, into the condensing apparatus so, that the air-volume compressed by the
air-pump M, M first passes through the tubes which are heated by exhaust-
steam of 10°, then through the tubes heated by exhaust-steam of 110°, and so on
through the tubes heated to a higher degree.
PPP are the partition-boxes into which the exhaust-steam of different
tensions is led.
Through this increasing heating of the heating tubes along which, as in the first
example, fluid flows for evaporation, the compressed air volume conducted through
pipe is able to carry a larger quantity of evaporized fluid for after having
saturated itself for the greater part with steam at the tubes beated with exhaust-
steam of 100°, the more heated tubes in the following partitions p', p², p³ give it an
opportunity of increasing its amount of steam, so that through regulating the degree
of temperature one is enabled to utilize the far greater part of the latent heat contained
in the exhaust-steam through evaporation of fluid, and the ensuing increase of volume
of the air flowing through the vaporizing apparatus.
In order to arrive at the most perfect results possible of using the latent heat of
exhaust-steam, it is desirable, to make the compressed air-volume obtained from the
principal cylinder, as large, as that of the steam-volume used in the cylinder, as
naturally in consequence of this increase of the air-volume obtained-the latent heat
of the exhaust-steam used in the principal cylinder, will be more easily absorbed.
Therefore, in order to increase this quantity of compressed air, an auxiliary cylinder C
has been placed, Fig. 3. which is not fed by steam from the principal boiler, but by
a mixture of steam and air from the conduit-pipe R. In this instance, a part of the
mixture of air and steam contained in the vaporizing apparatus is used as an auxilliary
to the steam-cylinders a¹, a² working with different expansions.
Now in order to arrive at a perfect utilisation of the latent heat of the exhaust-
steam, one may specially heat the compressed air volume before and after the operation
of vaporisation and thus render it still more suitable for the absorption of evaporated
fluid. This may be applied to the simple apparatus Fig. 1 as well as to the gradual
process, Figs. 2 & 3. Figs. 4 & 5 show this heating of the air-volume during its.
passage through the vaporizing apparatus in the gradual process.
Figs. 6 & 7 represent the same after its. passage through a number of heating-
tubes.
The following may serve to explain Figs. 4 & 5.
P, p p p are the receptacles into which the exhaust-steams of different tension
and temperatures is led & which heats the tubes; these tubes are covered with a
substance which absorbs moisture, and are connected with each other.
are
They serve, as in the first apparatus, for heating and vaporizing the fluid which
flows over them from the pipes 15. Between these tubes 1, heating-tubes
arranged which are heated from the receptacle and by extra-steam. The compressed
air flows in through the pipe and flows upwards between the tubes and h & is
heated on the tubes and at the same time absorbs the evaporated fluid from the
heated tubes and their covers e. As mentioned above, the heating of the air-volume
through the tubes increases its capacity of absorbing the evaporated fluid.
The apparatus, Figs. 6 & 7, distinguishes itself from that represented in figs. 4 & 5,
only by its construction. As shown in fig. 7, the heating, tubes are arranged above
a number of vaporizing tubes and serve to heat the mixture of air and steam
mounting upwards from the heating tubes (at the left Fig. 7.) resp. entering into
the heating tubes (at the right Fig. 7).
Fig. 6 represents the front-view of three of such double apparatuses placed side by
side; Fig. 7 shows them in cross-section.
Dated this 4th day of September 1888.
1
ATEXEIVE
VY 117
ELM SCHMIDT.
By A. Kuhnt & R. Deissler,
8, Alexanderstrasse, Berlin C., Germany..

page_text: COMPLETE SPECIFICATION. .
Method of Utilizing the Latent Heat of Exhaust-steam.
I, WILHELM SCHMIDT of Halberstadt, & Plantagen Strasse, Germany, civil 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:
My invention consists in a method of utilizing the latent heat of exhaust steam.
With the steam-engines known up to the present, the exhaust-steam--that is to say
its latent heat is utilized only to a very small extent through condensation, heating
the feed-water &c.; the greater part of this latent warmth is however lost.
The purpose of the method described below and illustrated in figs. 1-7 of the
drawings, sent in with provisional application, is to arrive at a better utilization of
this steam containing latent heat.
The proceeding essentially consists in first making the working steam act in a
steam-engine and by it, compressing air and in conducting the exhaust-steam of
this engine into an indirect acting vaporizing apparatus through which the com-
pressed air passes and whereby this air is made to absorb Aluid in the shape of
steam. The fluid evaporates at the vaporizing surfaces, which are heated by the
exhaust-steam. Thus it is possible that the vaporized fluid, which naturally takes
the tension of the compressed air, increases the quantity of the compressed air-
volume; the tension thus increased may be used in any manner whatever in other
engines.
From the above it is clear, that the increase of quantity has been obtained in
utilizing the latent heat of the exhaust-steam.
Fig. 1 represents a simple arrangement of this method.
A is the steam-cylinder in which the live-steam is expanded from 6 atmospheres
to 1 atmosphere..
B is the air-compressing cylinder in which air is compressed from 1 to about
6 atmospheres. The exhaust-steam escapes from the two pipes and through
the pipe into the chamber from where it fills the heating-tubes . From the
pipes water flows over these heating-tubes and which flows along their surface
and which in streaming down, is evaporated by the heated tubes 1, this evaporated
fluid is met by the air compressed to 6 atmospheres and which flows from the air
pump B through pipe and absorbs the evaporated volume and the result is a
mixture of compressed air and steam of the same tension as the compressed air.
This mixture of air and steam escapes through the pipes R and may be used at
pleasure in motors. It must be pointed out that through the admixture of air this.
working volume suffers very little loss through condensation in the conduit-pipes
and that this mixture, therefore, is specially suitable for separate motors far apart
from each other. .
The exhaust steam in the box 13 and in the tubes will be condensed in consequence
of the action of the water from and the water resulting will gather in the box 1³,
from whence it is led into the pipes 15 by a mechanical contrivance and used for
passing over the heating-tubes 1. All of the steam not condensed, part of it is be
allowed to escape from the box 13, which is suitably supplied with a discharge-valve,
so that the tension in this box 73 can be kept at one atmosphere.
The arrangement as represented in fig. 2, serves to arrive at a more perfect utili-
zation of the exhaust-steain, respectively the latent heat of the saine; in this case the .
proceeding is a gradual one, working with exhaust-steam of increasing tensions.
The two steam-cylinders a' a² work with different expansions so, that on the back
side of the piston in a' there is an expansion from 6 to 1 atmospheres, on the other
side an expansion from 6 to 1, 5 atinospheres and on the back-side of the piston
in a an expansion from 6 to 2, 5 atmospheres and on the other from 6 to 2
atinospheres.
•
The exhaust-steam of different tensions thus obtained, which also possesses different
temperatures of 100°, 110°, 120° respectively 127° is conducted through the tubes s¹,

page_text: s2, 3, sinto the condensing apparatus so, that the air volume compressed by the air-
pump M M first passes through the tubes which are heated by exhaust-steam
of 100°, then through the tubes heated by exhaust-steam of 110°, and so on through
the tubes heated to a higher degree.
P P P p are the partition-boxes into which the exhaust-steam of different
tensions is led.
Through this increasing heating of the heating tubes along which, as in the first
example, fluid flows for evaporation, the compressed air-volume conducted through
pipe is able to carry a larger quantity of evaporized fluid for after having saturated
itself for the greater part with steam at the tubes heated with exhaust-steam
of 100°, the more heated tubes in the following partitions p', p², p³ give it an
opportunity of increasing its amount of steam, so that through regulating the degree
of temperature one is enabled to utilize the far greater part of the latent heat
contained in the exhaust-steam through evaporation of fluid and the ensuing increase
of volume of the air flowing through the vaporizing apparatus.
In order to arrive at the most perfect results possible of using the latent heat of
exhaust-steam, it is desirable to make the compressed air-volume obtained from the
principal cylinder as large as that of the steam-volume used in the cylinder, as
naturally in consequence of this increase of the air-volume obtained-the latent heat
of the exhaust steam used in the principal cylinder, will be more casily absorbed.
Therefore, in order to increase this quantity of compressed air, an auxiliary
cylinder has been placed. Fig. 3 which is not fed by steam from the principal
boiler, but by a mixture of steam and air from the conduit-pipe R. In this
instance a part of the mixture of air and steam contained in the vaporizing
apparatus is used as an auxiliary to the steam-cylinders a¹ a² working with different
expansions.
Now in order to arrive at a perfect utilization of the latent heat of the exhaust-
steam, one may specially heat the compressed air-volume before and after the
operation of vaporization and thus render it still more suitable for the absorption
of evaporated fluid. This may be applied to the simple apparatus fig. 1, as well
as to the gradual process, figs. 2 and 3. Figs. 4 and 5 show this heating of the
air-volume during its passage through the vaporizing apparatus in the gradual
process. Figs. 6 and
represent the same after its passage through a number of
heating-tubes.
The following may serve to explain figs. 4 and 5.
p p p p are the receptacles into which the exhaust-steam of different tension and
temperatures is led and which heats the tubes; these tubes are covered with a
substance which absorbs moisture and are connected with each other. They serve, as
in the first apparatus for heating and vaporizing the fluid which flows over them from
the pipes 1. Between these tubes heating-tubes. are arranged which are heated
from the receptacle and by extra-steam. The compressed air flows in through the
pipe and flows upwards between the tubes and hand is heated on the tubes and
at the same time absorbs the evaporated fluid from the heated tubes and their
covers e. As mentioned above, the heating of the air-volume through the tubes h
increases its capacity of absorbing the evaporated fluid.
h
The apparatus, figs. 6 and 7, distinguishes itself from that represented in figs. 4
and 5, only by its construction. As shown in fig. 7, the heating-tubes are arranged
above a number of vaporizing tubes and serve to heat the mixture of air and steam
mounting upwards from the heating tubes (at the left fig. 7) respectively entering
into the heating tubes (at the right fig. 7).
Fig. 6 represents the front-view of three of such double apparatuses placed side by
side; fig. 7 shows them in cross-section.
;
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is:
1.) A method of utilizing the latent heat of exhaust-steam which consists in first

page_text: using live-steam to compress air and using the exhaust-steam from this air com-
pressing engine for warming and evaporating water, which is mixed with the
compressed air, substantially and for the purpose as described.
2.) A method of utilizing the latent heat of exhaust-steam which consists in first
using live steam of different pressures in one or more cylinders or engines to compress
air and using the exhaust-steam from the said cylinder or cylinders, in the order of their
temperature for warming and evaporating water, substantially and for the purpose as
described.
3.) A method of utilizing the latent heat of exhaust steam which consists in first
using live steam to compress air and using the exhaust-steam from this engine for
warming and evaporating water, which is mixed with the compressed air and heating
this compressed air before or during its passage through the evaporating apparatus
for the purpose of increasing its absorbing powers substantially as described.
Dated Berlin this 25th day of May 1882.
WILHELM SCHMIDT.
By A. Kuhnt & R. Deissler,
38, Alexander Strasse, Berlin C.