Improvements in or relating to the Accumulation of Heat, and to its Transmission to Water or other Liquid, or to Gases.
Year: 1898

page_text: Improvements in or relating to the Accumulation of Heat, and to its
Transmission to Water or other Liquid, or to Gases.
2
I, LUCIEN MAURICE, of 68, Rue de Rennes, Paris, France, Engineer, do hereby
declare the nature of this invention, to be as follows:-
This invention relates to the formation of accumulators of heat, composed of
bodies arranged between the source of heat and the water, or other liquid, to be
evaporated, or superheated, or as a true generator, or superheater, without furnace,
said bodies being heated by convenient means to a high temperature and
employed in suitable apparatus whereby the heat stored in such accumulator can
be recovered, and utilized.
The invention is based on the property possessed by certain bodies, such as
nitrate of potassium, employed either alone or mixed with other bodies, and
which when submitted to heat, fuse and then remain liquid at high temperatures
without decomposing, and without acquiring any appreciable pressure.
Suitable
for use with the nitrate of potassium, may also be mentioned the nitrates of
calcium, chromium, strontium, barium, sodium, lead, and others of a like nature.
These bodies are so arranged in the apparatus as to absorb heat from any suit-
able source, and then to part with it, when accumulated, for the purpose of
evaporating water, or other liquid, for obtaining motive power suitable for
various purposes.
By the use of the above named medium or agent, according to my invention,
the chance of explosion, due to overheating, is entirely avoided, as the medium
or agent becomes heated without acquiring pressure, and then gradually parts
with its accumulated heat.
Mixtures composed of the above mentioned bodies, and most suitable for use
for the purposes of my invention, are those known to scientists as " eutectic "
mixtures, ie., mixtures notable for their fixity of point of fusion.
In applying the invention, say to a tubulous boiler, I provide the water circu-
lating tubes with a jacket or outer tube, and fill the space between them with
one of the before mentioned bodies, or mixtures, and then heat them, by suitable
means, until sufficient heat is stored up therein, after which the primary source
of heat can be withdrawn, and the heat from the accumulator serve to evaporate
the water, or other liquid, in the boiler.

page_text: Improvements in or relating to the Accumulation of Heat, and to its
Transmission to Water or other Liquid, or to Gases.
I, LUCIEN MAURICE, of 68, Rue de Rennes, Paris, France, 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, reference being had to the accompanying drawings and to the letters
and figures marked thereon, that is to say:
My invention has for its object the production of an accumulator of heat suit-
able for use in numerous applications, such as in boilers, or in other apparatus,
as an intermedium between the source of heat and the water, or other liquid to
be evaporated or superheated, or as a true generator or superheater, without
furnace, by parting with the heat previously stored therein.
دو
My invention is a commercial application of the property possessed by certain
bodies, such as nitrate of potassium, employed either alone or mixed with other
bodies, as will be hereinafter further explained, of fusing and remaining liquid
at high temperatures without becoming decomposed and without any appreciable
pressure. I will take as an example, in order to explain my invention, the
eutectic mixture (the word " cutectic is explained further on) of nitrate of
potassium and nitrate of sodium in the proportion of 67 10% of the former body.
In the solid state, the density of this mixture is about 2'13; in the liquid state,
it is about 2; its mean specific heat is sensibly equal to 05; its latent heat
of fusion is 35 calories. It only acquires an appreciable pressure when above
525° C., by slowly parting with ogygen. Hence, a ten horse power motor con-
suming 20 kilos. of steam per horse power, and which would thus need 200 kilos.
of steam per hour, would work without a fire for one hour with about 600 kilos.,
or 300 litres of mixture forming the heat accumulator.
The volume of the mixture serving as accumulator would thus, at the lowest
computation, be equal to 1% of the volume of water to be evaporated. In the
above example I have chosen very unfavourable circumstances, but in practice
when the heating is effected simultaneously with that of the liquid heat-accumu-
lator, of the water, and of the metallic mass of the apparatus, the yield will be
increased in large proportions and almost doubled. Finally, and again at the
lowest computation, the volume of the accumulator mixture will be, at the most,
equal to the volume of water to be evaporated. The mixture previously men-
tioned is not the only one which can be used to thus form a heat accumulator.
The following mixtures are suitable, and any one of them can be selected according
to the circumstances of the application in view. The proportions can also be
varied. Nevertheless, the proportions indicated correspond to what scientists

page_text: designate the eutectic mixture, remarkable by the fixity of the point of fusion.
According to the case, one of the following mixtures can be taken:
0710
I give below, so that the invention may be readily understood, one form of
its application to a fireless boiler.
The annexed drawings show one mode of construction suitable to this applica-
tion.
Fig. 1 is a longitudinal section of the boiler, and
Fig. 2 is a half transverse section thereof on the line A B of the previous figure.
A series of concentric tubes are arranged between two tube plates and 2,
the annular space 3 between the two tubes being filled with a mixture of nitrates,
or other equivalent mixture, forming an accumulator of heat. This annular space
is closed at both ends, but the central tube 4 of each element is in communication
with the two tube plates so as to permit the circulation of the water. The
tubular system or arrangement thus formed, (and which works like an ordinary
generator) is heated so as to bring the accumulator mixture to a very high tem-
perature, while keeping it below that at which it decomposes; the heat thus
accumulated can then serve to produce, after the extinction of the fires, the steam
necessary for working motors for carriages, or steam trams, or for any other
purpose. With the accumulator mixture just mentioned, there is no risk of
exceeding the limit of temperature at which the mixture decomposes,
as on the one hand the tubes most exposed to the fire rarely attain in the furnace
a temperature of 525° and, on the other hand the commencement of the decom-
position of the mixture is made known by the disengagement of oxygen, and
for this purpose each one of the annular spaces 3 containing the mixture can be
connected by a small tube 5 to a discharge tube 6, through which the gas
produced escapes in a continuous and easy manner, as may be ascertained
by any suitable means, as for instance by a sensitive manometer. Besides the
advantages obtainable in various industries by this system of heat accumulator,
it will be readily understood that any chance of explosion by overheating is

page_text: obviated, as, up to the limit to which the temperature of the mixture employed is
raised, this latter becomes heated without acquiring pressure. It will thus be
clear that this arrangement can be applied, as before stated, to boilers working
under normal conditions, and for which it is desired to ensure absolute safety;
the annular space 3 filled with the material serving as an intermedium and
protecting the tubes 4, for the circulation of the water, from overheating, at the
same time that through the volume of heat contained in the accumulator body,
the continuity of the temperature is ensured even in case of sudden variations.
in the working of the furnace.
Obviously, I may vary, according to the conditions of the application, all
accessory circumstances which might present themselves during the working of
my invention, especially the nature and proportions of the bodies serving as heat
accumulators. I may also reverse the reciprocal positions of the liquid to be
evaporated, and the bodies serving as accumulators, the internal tubes ΟΙ
recipients 4 then containing the accumulator body, and the annular space 3
the liquid to be evaporated.
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 commercial application, to the formation of accumulators of heat of
bodies such as those hereiubefore mentioned, or their equivalent, heated in any
manner to a high temperature, the utilizing apparatus being so arranged as to
recover from such accumulator the heat stored therein, substantially as described
and shewn by way of example in the annexed drawings.
2. The commercial application of the bodies hereinbefore mentioned (or their
equivalent) to constitute generators of steam, or to improve the working of boilers
of any type, by interposing between the source of heat and the liquid to be
evaporated, an intermediate agent to ensure the regularity of transmission of
the heat, substantially as described and shewn by way of example in the annexed
drawings.
Da
ERNEST DE PASS,
Chartered Patent Agent,
78, Fleet Street, London, and 5a, Market Street, Nottingham,
Agent for the Applicant.