A Compact Natural Gas Pyrolysis Reactor for Hydrogen Fueling Stations
Abstract
With the increasing amount of greenhouse gases causing more natural disasters and
sea level rise, there is a clear need for a global energy transition to less polluting
fuels. A possible solution to this problem is converting a portion of the
transportation sector fuel to hydrogen. In this thesis, the issues associated with such
a transition are discussed and reasonable solutions are proposed. Numerous
methods of hydrogen production are explored and compared on the basis of
electricity consumption and CO2 emission. A plant size of 1250 kg liq. H2/day is
chosen based on California regulated hydrogen refueling credits (HRI) that
guarantee payment for produced hydrogen, regardless of the amount sold. A
process simulation for hydrogen generation and liquefaction is carried out using
Aspen Plus V10® to estimate equipment sizes. CAPEX and OPEX cost are
estimated using correlations based on industrial standards. It was determined that,
at this scale, only hydrogen generation is currently profitable. The high capital and
operating cost of liquefaction is not justified unless intended for long term storage.
Instead, high pressure or hydride tanks are recommended as storage media for
modular filling stations.