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Annual Report 2014
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The most recent achieve-
ment is the installation of
a large test rig of 150 kW
capacity installed at Tiller
during 2014.
Installation of the 150 kW CLC rig.
(Photo: Øyvind Langørgen)
The clue in CLC is the way the oxygen is produced. The standard
method for oxygen production is by cryogenic distillation of air
at very low temperatures. CLC uses instead that metal particles
can be rapidly oxidized in air at high temperatures, in the order
of 850 – 1000°C. That is, the particles extract oxygen from the air.
The resulting metal oxide particles are then transported to the fuel
where the oxygen is released and used for burning the fuel. There-
after they are transported back in order to continue the “looping”
process as illustrated in the figure. This can be less energy intensive
and costly than standard oxygen production methods.
The main challenges in CLC are development of suitable metal
oxide particles as well as appropriate reactor and control systems
for long time continuously operation. The metal particles must
survive and do the job at high temperatures, they should ideally
extract and release as much oxygen as possible in as short time as
possible (some seconds) and they should not break down into fine
powder, or agglomerate and clog into larger particles. The reactor
and control system must ensure stable operation, high circulation
of particles and full burn-out of fuel.
The most recent achievement is the installation of a large test rig of
150 kW capacity installed at Tiller during 2014. The rig is intended
for gaseous fuels. The reactors are 6 meters high with diameter
of 240 and 160 mm. At this size small scale effects are of minor
importance and the results obtained can more easily be transferred
to even larger test rigs and demos. Preliminary tests have been
done, both at low and high temperatures, but at time being without
fuel gas supply. The first tests with fuel gas supply and real reactive
CLC operation is planned within 2014. The 150 kW rig is so far the
last and largest step in the chain of development and infrastructure
built up within the CLC activity of BIGCCS.
Principle of Chemical Looping
Combustion.
Oxygen
depleted air
CO
2
+ H
2
O
MeO
Me
Exoth.
Endoth.
Exoth.
Fuel
Air
Metal
oxide
reduction
Metal
oxidation