Crown offers various processes that can be part of a biofuel plant.
For other biofuels, such as renewable diesel or other products derived from fatty acid, the process is usually similar to what is done for biodiesel pretreatment, with two exceptions. First, the requirement for metal content is typically more strict for renewable diesel because of the downstream fuel processing, so the degumming/filtration step from biodiesel pretreatment is modified to remove even more of the metals. Second, the renewable diesel specification does not normally restrict the amount of free fatty acid (FFA), so an FFA stripping step is not necessary.
Flexibility is always important. While a vertically integrated plant may not need to provide feedstock for both a biodiesel and a renewable diesel plant, the relative similarity in the processes for both biodiesel pretreatment and renewable diesel pretreatment may make an independent processor think twice about which future products a plant should be able to make.