Q697. How should fuels and feedstocks be reported for hydrogen production process units?

A697. Per 98.163, fuels and feedstocks should be reported for each hydrogen production process unit.  If a facility used both natural gas and refinery fuel gas to produce hydrogen in a single process unit, there should be one unit reported with two feedstocks, not two separate hydrogen production process units with one feedstock each.  For the purposes of the material balance approach in 98/163(b), recycled streams should not be considered feedstocks as the carbon in these recycled streams has already been accounted for in Equations P-1, P-2, or P-3, which  account for all carbon in the direct (non-recycled) fuels and feedstocks.  For example, PSA off-gas recycled to the SMR furnace should not be considered as a separate feedstock because the carbon in this gas stream has already been accounted for in the direct feedstock streams.