Improvements in the Production of Combustible Gases by Means of Gas Generators.
Year: 1898

page_text: Date of Application, 6th Aug., 1898-Accepted, 24th Sept., 1898
:
COMPLETE SPECIFICATION.
Improvements in the Production of Combustible Gases by Means of
Gas Generators.
I, LUDWIG MOND, of 20, Avenue Road, Regent's Park, in the County of London,
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:-
Combustible gases are generally produced by the incomplete combustion of coal
or other fuel in gas generators into which air more or less charged with water
vapour is introduced.
My present invention has for its object to increase the yield of the combustible
gases so obtained from a given quantity of coal. For this purpose I add to the
air, more or less charged with water vapour at ordinary or at a moderate temper-
ature, as is now generally used in gas generators, gases containing
carbon dioxide, which latter in contact with the incandescent fuel in
the generator is reduced to carbon monoxide. In this way every volume of carbon
dioxide introduced into the generator yields two volumes of carbon monoxide,
half of which is derived from the carbon added in form of carbon dioxide, and is
an addition to the combustible gases obtainable from the fuel by the use of air
alone.
The reduction of the carbon dioxide into carbon monoxide consumes however
a certain amount of heat (calories) and thus reduces the temperature of the
incandescent fuel.
In order to maintain this temperature sufficiently high for the further reduction
of carbon dioxide it is therefore necessary to limit the amount of carbon dioxide
introduced into the generator, so that a sufficient quantity of coal is burned by
means of the oxygen of the air to produce in the generator an amount of heat
equivalent to that consumed by the reduction of the carbon dioxide.
In practice I find that, under ordinary circumstances, I can add carbon dioxide
until the gases entering the generator contain for every 100 volumes of oxygen
45 volumes of carbon dioxide, but this quantity varies very considerably with the
quality of the fuel and the amount of steam with which the air has been charged.
I prefer to employ the maximum quantity of carbon dioxide admissible to main-
tain the generator and consequently the gases leaving it at the lowest possible
temperature compatible with the effectual reduction of the carbon dioxide. This
enables me to economise a considerable part of the heat which is ordinarily lost
when the gases leave the generator at a high temperature and has the further
advantage that the formation of clinkers in the producer is avoitled and that the
ashes can be readily removed.
As a source of carbon dioxide the gases from lime kilns the natural gases, which
emanate in many places from the earth or any other gases containing sufficient
carbon dioxide can be used.
If they contain more than 20% carbon dioxide a generator gas is produced of
a higher heating value than is ordinarily obtained.

page_text: 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:
The improvement in the production of combustible gas in gas generators, which
consists in adding a certain quantity of gases containing carbon dioxide to the air
more or less charged with water vapour at ordinary or at a moderate temperature
as is generally used for the gasification of coal in gas generators so as to obtain from
a given quantity of coal a larger yield of combustible gases and to maintain the
gas generator at a suitable temperature.
Dated this 5th day of
1000
WM. P. THOMPSON & Co.,
Patent Agents, of Liverpool, Manchester, Birmingham, and London.