Improvements in or relating to the Production of a Mixture of Air and Water Vapour, especially applicable for Gas Producers.
Year: 1896

page_text: Date of Application, 14th Dec., 1896
Complete Specification Left, 8th Oct., 1897-Accepted, 27th Nov., 1897
Improvements in or relating to the Production of a Mixture of Air
and Water Vapour, especially applicable for Gas Producers.
I, LUDWIG MOND, of Winnington Hall, Northwich, in the County of Chester,
Manufacturing Chemist, do hereby declare the nature of this invention to be as
follows:
In various industries and more particularly in the manufacture of ammonia
from coal and other nitrogenous fuel with simultaneous production of producer
gas, for which I obtained Letters Patent Nos. 382183, 392383, 897385, 1244093, 1678195,
mixtures of air and water vapour or rather air saturated or nearly saturated at
temperatures between 80 and 90° Centigrade with water vapour is required in very
large quantities. This present invention has for its object the production of those
mixtures of air and water vapour at a very small cost. In my Patent No. 897385
I have described a method, by which I obtain air saturated with water vapour
at 70-75 Centigrade by the utilisation of the heat stored up in the producer gas
obtained from the coal, but this mixture of air and water vapour does not contain
enough of the latter to obtain the largest yield of ammonia from a given quantity.
of coal.
In order to obtain a mixture of air and water vapour such as is required, I heat
air which may already contain a certain amount of water vapour to a convenient.
temperature say 300 to 500 Centigrade. For heating the air I prefer to use an
intermittent or continuous regenerator, which may be heated by any hot waste
gases available, such as the exhaust gases from gas engines or the waste gases
from boiler or any other furnaces, and bring the heated air into intimate contact
with water preferably heated to or near its boiling point. The temperature of the
air is thus reduced and the heat that was stored up in it is utilized in evaporating
the water, the water vapour produced mixing with the air and enriching it in that
constituent to the extent required.
In some cases, for instance, when the source of the waste heat is at a considerable
distance from the gas producers, it may be convenient to transfer this waste heat
in the first instance to water, preferably under pressure, or to another solution or
liquid of a higher point by means of any suitable heating apparatus, and to
transport the hot water or liquid obtained to another apparatus, in which
it gives up the heat stored therein to air, which may already be partially charged
with water vapour. For this purpose apparatus of the same construction as
surface-condensers may he advantageously, used for heating water and other liquids
and also for subsequently heating by means of them, the air to be loaded with
water vapour, which heated air is then brought into intimate contact with water
as described before. If by these means the air is not charged sufficiently with
water vapour by passing it through one heating and moistening apparatus, the air
insufficiently charged with water vapour may be passed through a second heating
and moistening apparatus of the same description and through an additional
number if required.

page_text: Another way of obtaining my object consists in the following:
I heat water in a suitable apparatus under pressure to a temperature above
100 Centigrade and bring this superheated water into intimate contact with air,
which may already be partially charged with water vapour in an apparatus, which
is under ordinary atmospheric pressure. A certain amount of this water will
immediately be liberated as steam and a further quantity will be evaporated by
contact with the unsaturated air, which will reduce the temperature of the water
considerably under 100 Centigrade.
Datod this 10th day of December 1896
W. P. THOMPSON & Co.,
Of 322 High Holborn, London, Patent Agents for the Applicant.
Improvements in or relating to the Production of a Mixture of Air
and Water Vapour, especially applicable for Gas Producers.
I, LUDWIG MOND, of Winnington Hall, Northwich, in the County of Chester,
Manufacturing Chemist, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
In various industries and more particularly in the manufacture of ammonia
from coal and other nitrogenous fuel with simultaneous production of producer
gas, for which I obtained Letters l'atent Nos. 382183, 392383, 897385, 1244093, 1678195,
mixtures of air and water vapour or rather air saturated or nearly saturated at
temperatures between 80 and 90° Centigrade with water vapour is required in very
large quantities. This present invention has for its object the production of those
mixtures of air and water vapour at a very small cost. In my Patent No. 897385, I
have described a method, by which I obtain air saturated with water vapour at
20 475 Centigrade by the utilisation of the heat stored up in the producer gas
obtained from the coal, but this mixture of air and water vapour does not contain
enough of the latter to obtain the largest yield of ammonia from a given quantity
of coal.
In order to obtain a mixture of air and water vapour such as is required, I heat
air, which may already contain a certain amount of water vapour, to a convenient
temperature, say 300 to 500 Centigrade, and I then bring the heated air into
intimate contact with water preferably heated to near its boiling point. For
heating the air, I prefer to use an intermittent or continuous heating apparatus
which may be heated by any hot waste gases available, such as the exhaust gases
from gas engines or the waste gases from boiler-or any other furnaces. The
temperature of the air is reduced by its coming into contact with the water and
the heat that was stored up in it is utilised in evaporating the water, the water
vapour produced mixing with the air and enriching it in that constituent to the
extent required.
In some cases, for instance, when the source of the waste heat is at a considerable
distance from the gas producers, it may be convenient to transfer this waste heat
in the first instance to water, preferably under pressure, or to another solution or
liquid of a higher boiling point by means of any suitable heating apparatus, and
to transport the hot water or liquid obtained to another apparatus, in which it
gives up the heat stored therein to air which may already be partially charged
with water vapour.
This part of my invention is best described by aid of the accompanying drawing,

page_text: b
in which A is a gas engine or other source of waste hot gases; pipe leading there-
from, B surface heater formed of an upper and lower chamber connected by a
large number of small tubes and surrounded by a casing. The waste gases enter
this casing at the top through the pipe 6 and escape from it at the bottom by the
chimney 62. Water at the same time enters this chamber at the bottom through
the pipe and escapes from it through the pipe 63. B is a similar
heater at a long distance from heater B but in any convenient posi-
tion near the gas producer. It is supplied with the hot water from
heater B through the pipe 63 63. This water gradually descends through the
tubes to the bottom chamber and escapes by pipe . P is a pump pumping the
water from pipe + to pipe bb and thus back again into water heater B. These
two water heaters are preferably kept absolutely full of water under a constant,
and considerable pressure which in the first heat transmitter is heated to a high
temperature. They can be supplied if desirable with safety valves and also the
pump P can have an additional source of supply of water 2 to allow for leakage.
Air enters the casing of heater B at I near the bottom and escapes near the top
through the pipe C to near the bottom of the scrubber C. Scrubber O is supplied
with either hot or cold water, preferably the former, through pipe C and as the air
passing up from pipe el to its exit by pipe comes in contact with the water it
converts a large quantity of this water into steam and carries this steam with it to
the producer G. Any water which is not evaporated by this means escapes
through the pipe C to the steam trap D of any wellknown description. This trap
allows the water to escape without, allowing the air and steam to pass.
Instead of passing air through the casing of the heat interchanger B³, as before
described, I sometimes pass cold or warm water through this casing, and bring
this water, which I preferably keep under pressure, after it. has taken up the heat
of the water or liquid circulating through the two heatons B and B', into intimate
contact with the air that I wish to saturate with water vapour.
In place of using water as already described under pressure and continuously
over, I may use any other suitable liquid such as brine, calcium chloride, etcetera,
for the same purpose.
If by these means the air is not charged sufficiently with water vapour by passing
it through one heating and moistening apparatus, the air insufficiently charged
with water vapour may be passed through a second heating and moistening appar-
atus of the same description and through an additional number if requireil.
Another way of obtaining my object consists in the following:
I heat water in a suitable apparatus under pressure to a temperature above
100 Centigrade and bring this superheated water into intimate contact with air,
which may already be partially charged with water vapour in an apparatus, which
is under ordinary atmospheric pressure. A. certain amount of this water will
immediately be liberated as steam and a further quantity will be evaporated by
contact with the unsaturated air, which will reduce the temperature of the water
considerably under 100 Centigrade.
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. The process of producing a mixture of air and water vapour such as described
for gas producers, which consists in heating air by means of hot gases in a con-
tinuous or intermittent superheater, and then bringing the hot air into intimate
contact with water (preferably hot water) in a scrubber or other suitable apparatus.
2. The system of utilising the heat of waste gases at a distance for loading air
with moisture, which consists in transferring the heat of the hot gases to water or
other liquid carrying the hot liquid the distance required in pipes, and transferring
the heat stored in it in a heat transmitter (a) to other water which is brought in
direct contact with the air or (b) to air which is brought into intimate contact with
water preferably previously heated.

page_text: 3. The improvement in the process substantially as described in Claim 2, which
consists in using the same water over and over again as a continuous circulation
under pressure.
4. The process of producing a mixture of air and water vapour such as (and for
the purposes) described, which consists in heating water under pressure to above
100 degrees Centigrade and bringing this superheated water into intimate contact
with air, preferably partially charged with water vapour, in an apparatus which
is under ordinary atmospheric pressure.
Dated this 5th day of October 1897.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.