In this study, a pilot scale of 100 t/year biodiesel production system, mainly consisting of a fixed-bed and
a down-stream plug-flow reactors, was setup to test different feedstock oils, especially a kind of highacidified
oil, trap grease, for their feasibility as biodiesel feedstock in China. The tested oils include three
kinds of typical oil from Guangdong Province, China: rapeseed oil, Chinese wood oil, and trap grease. At
the same time the optimum residence time for a plug-flow reactor to perform transesterification reaction
was investigated in this study. At the temperature of 65 C, methanol/oil molar ratio of 6:1 and KOH load
of 1.2 wt% of oil, the optimum residence time was found to be 19 min. A type of ion-exchange resin was
used to fill in the fixed-bed reactor and used as the esterification catalyst for pretreating on the highacidified
oil. For the fresh catalyst, the acid value of trap grease could be reduced from 114 mg KOH/g to
about 2 mg KOH/g after 13 h at temperature 75 C, catalyst load of 15 wt% of oil, methanol addition of
20 wt% of oil. The lifetime test for the catalyst indicated that its life is over 30 days. The quality of
biodiesel derived from three feedstock oils is compared with newly published China BD100 standard of
GB/T20828-2007. A comparison of the results reveals that the biodiesel generated through this system
could satisfactorily meet China BD100 standard. It indicates that the designed process in this system has
a good adaptability for different kinds of oil.