As a clean energy supply, hydrogen could revolutionize the heating technology sector. The first experiments are already on the market and ebm-papst is also prepared for gas condensing boilers featuring climate-neutral fuel with its NRV 118 Hydrogen composite system.
Technical requirements
Many manufacturers are working on converting their condensing units to
clean energy supply with as few technical changes as possible. Hydrogen
is the chemical element with the lowest density, which is why components
in condensing boilers have to be adapted. The combustion behavior
requires special attention. As the flame speed is eight times higher
than with methane, the ignition times in the combustion controller have
to be checked and adjusted if necessary. Hydrogen has a lower heating
value than methane but its Wobbe index, important for the
interchangeability of fuel gas, is almost as high. For an optimal
mixture in the venturi, the gas/air ratio controls have to be designed
correctly. As a result, the interaction between the gas blowers, venturi
and gas valve is of great importance.
NRV 118 ready for H2
The established NRV 118 composite system from ebm-papst is already
designed for use with a hydrogen content of up to 10% without any
changes. Thanks to a few changes, the composite system is even suitable
for use with 100% hydrogen. This has now been proven in several
investigations and initial field tests. The leak tightness of the gas
valve and blower has been increased and the materials used checked for
their suitability. Thanks to a special pre-mixing device, the NRV 118
hydrogen is ideally suited for hydrogen use. The "premix" gas blower
compensates for the disadvantage of the lower Wobbe index and calorific
value of hydrogen, while at the same time increasing burner pressure
loss due to the gas/air mixture upstream of the fan. Complex control
cables, as for operation in excess pressure, are not required.
Furthermore, higher modulations can be run because the gas valve can be
optimally controlled by negative pressure.
It will be some time before the clean fuel can be used extensively for heating, but if developments continue in science, politics and industry, this could become reality in the not-too-distant future.
Contact: Lisa
Phone: +86 13420990032
Tel: +86 755 8386 8829
Email: Lisa@jfun.hk
Add: Add: Rm 5B13-1, 5 / F, Futian Market Building, 99 Fuhua Road, Futian District, Shenzhen