Hydrogenation is the chemical addition of
hydrogen to a hydrocarbon in the presence of a
catalyst, a severe form of hydrogen treating.
hydrogen is added to a molecule that is
unsaturated with respect to hydrogen. In either
case, the resulting molecules are highly stable.
Hydrogenator Design and Control
The use of hydrogen requires precautions against
creating an explosive mix of hydrogen and air.
Typically, a hydrogenation vessel undergoes a
pressure test followed by several nitrogen
purges before hydrogen is introduced. Similarly,
at the end of the reaction process, the vessel
is purged with nitrogen in order to leave it in
a safe condition. Normally, a hardwired safety
system confirms the pressure test and nitrogen
purge phases before allowing the hydrogen line
to be opened.
Hydrogenation requires high pressures to be
maintained in the reaction vessel - giving
problems over maintaining seals around agitators
which in some cases require additional seal
integrity checks or upgrades to incorporate
magnetic coupling systems.
Hydrogenation also tends to be a highly
exothermic reaction, resulting in demanding
temperature control requirements.
A control system must therefore provide
flexibility in the way in which accurate and
repeatable control of the hydrogenation
environment is achieved and will include the
following features:
|
