Hi Junling,
There really isn't a difference in the way that LEAP treats fuel consumption for energy or non-energy (i.e. feedstock) purposes. For clarity, I would suggest assigning a meaningful name, or category name, to fuels which are deemed "non-energy". You will also need to ensure that you avoid assigning any combustion-based emission factors to the branch.
The "non-energy fraction" variable is no longer part of the LEAP distribution.
Best,
Taylor