Biogas to Syngas through the Combined Steam/Dry Reforming Process: An Environmental Impact Assessment

The
combined steam/dry reforming (S/DR) technology was used to
produce syngas from clean biogas. In the reaction conditions proposed,
the catalytic bed can produce, without deactivation, a syngas with
a H2/CO ratio of ≈2 directly processable for methanol
or Fischer–Tropsch syntheses. Starting from the laboratory
data obtained in the industrial conditions, mass and energy balances
for the overall process were obtained from Aspen HYSYS simulations.
The environmental evaluation was performed by applying the life cycle
assessment (LCA) methodology, comparing different scenarios to the
current industrial route to produce syngas (autothermal reforming
or ATR of natural gas). The analysis showed that clean biogas-to-syngas
technology using reforming processes has the potential to reduce the
anthropogenic impact on the environment. The ReCiPe method showed
that when the combined S/DR process is conducted using clean biogas
also as a heat source, the CO2 balance turns negative,
ensuring that the whole process has excellent potential as carbon
capture and utilization (CCU) technology providing the lowest damage
in all categories. Its improvement would make it possible to further
reduce the environmental burden of the overall process, which is essential
for achieving sustainable development.