Peak Scientific Precision Hydrogen 1200cc, Руководство пользователя

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Principle of Operation
The Peak Scientific hydrogen generator produces high purity hydrogen gas(H
2
).
Hydrogen does not occur naturally on earth and must be formed via the decomposition
of other molecules, in this case via the splitting of water molecules into hydrogen and
oxygen in a process known as electrolysis.
The state of the art in water electrolysis is the Proton Exchange Membrane (PEM)
electrolyser. This technology was first described in the mid-1960s by General Electric as
a method for producing electricity for the Gemini Space Program and later adapted for
electrolysis. This process has been continually developed ever since. All Peak Scientific
hydrogen generators utilise PEM technology .
The most important element of the generator is the electrolyser cell where the
electrolysis reaction takes place. This consists of two electrodes (an anode and a
cathode), which are separated by the proton exchange membrane which gives the
technology its name. During operation, deionised water is fed to the anode of the
electrolysis cell where it is split into oxygen, protons and electrons with the aid of a
precious metal catalyst. The oxygen is vented to atmosphere from the generator. The
protons travel across the membrane and simultaneously the electrons travel around the
external electrical circuit. These protons and electrons then recombine at the cathode of
the electrolyser, again with the aid of a precious metal catalyst to produce the hydrogen
gas. The high purity of the hydrogen is assured by the membrane which completely
separates the hydrogen produced at the cathode from the oxygen being produced at
the anode. These processes are described by the following equations:
Cathode 2H
+
(aq)
+ 2e
-
= H
2(g)
Anode H
2
O
(l)
=
½
O
2(g)
+ 2H
+
(aq)
+ 2e
-
Deionised water is critical to the operation of the system and must have a purity of
1
µ
S/cm or better to prevent damage to the membrane.
Failure to use this grade of
deionised water will invalidate the 3 year cell warranty of the generator. The water is
automatically loaded (either at power up or periodically during operation) and the rate
at which the water is consumed depends on the amount of hydrogen being produced.
A small amount of the electrical energy is lost as heat and this is removed from the
generator by the ventilation system.
The Peak Scientific hydrogen generator produces hydrogen on demand. By maintaining
the user’s pre-set pressure and using this as a reference value, the generator will
produce the precise amount of hydrogen required. As soon as the demand ceases, no
further hydrogen will be sent to the user’s application. During this time bubbles may still
be observed in the separating tank. This is due to the generator maintaining its internal
pressure and ensuring that clean, dry hydrogen is available immediately on demand
when the user requires it.