Consultation about OleinCrystallizer

Hello, could I consult you some questions about OleinCrystallizer.

a) In https://github.com/BioSTEAMDevelopmentGroup/Bioindustrial-Park/blob/master/biorefineries/cane/systems/biodiesel_actag.py#L41-L45 and https://biosteam.readthedocs.io/en/latest/API/biorefineries/cane/units.html#:~:text=%5Bsource%5D-,Separations,PL%27)%2C%20melt_IDs%3D(%27AcTAG%27%2C)%2C%20order%3DNone),-%5Bsource%5D, there is the ```OleinCrystallizer``` unit. But when I looked through ```O1 = cane.Biorefinery('O1'), O1.oilcane_sys.units```, I didn't see the ```OleinCrystallizer``` unit, Can I consult you how to view a system with OleinCrystallizer unit?

b) In https://github.com/BioSTEAMDevelopmentGroup/Bioindustrial-Park/blob/master/biorefineries/cane/systems/sugar.py#L141, the ```BatchCrystallizer``` is used. Could I consult you what is the difference between ```BatchCrystallizer``` and ```OleinCrystallizer```? I study the source code of them in https://biosteam.readthedocs.io/en/latest/_modules/biorefineries/cane/units.html#OleinCrystallizer and https://github.com/BioSTEAMDevelopmentGroup/biosteam/blob/master/biosteam/units/_batch_crystallizer.py, It seems that the calculation method of Hnet is different, the Hnet of ```OleinCrystallizer``` is the difference between solid substance enthalpy in the outlet and inlet. Why is Hnet calculated differently?

c) If there is liquid state riboflavin and other impurities in the feed, I want to cool and crystallize the riboflavin to recover the riboflavin, and other impurities may also be precipitated during this process (I am not quite sure). Could I consult you which unit (```BatchCrystallizer``` and ```OleinCrystallizer```) shall I use?

d) In the source code of ```OleinCrystallizer``` (https://biosteam.readthedocs.io/en/latest/_modules/biorefineries/cane/units.html#OleinCrystallizer), could I consult you what is the meaning of ```solid_purity``` and ```melt_purity```?

Thanks for your help. Wish you a good day.