BayFAME®

The Configuration

The appropriate number of reaction and evaporation stages that should be selected depends mainly on the range of FFA content of the prospective feedstock as well as on the desired target residual FFA concentration, i. e. the inlet FFA specification of the downstream transesterification reaction. The figure on page 5 illustrates the dependence between FFA concentration in the feed and outlet of the esterification and the required number of reaction steps. For feedstocks containing only a few percent FFA such as e. g. crude vegetable oil a single reaction stage will be mostly sufficient to reduce the FFA concentration to a residual level that can be tolerated in the transesterification. A 2-stage configuration will be suitable for feedstocks with moderate FFA content ranging between 10 – 20 wt% FFA or equivalent mixtures of high FFA feed with vegetable oils and fats. If a third reaction stage is employed, feedstocks with FFA concentrations up to 100 wt% can be directly esterified. In case of feedstocks with varying FFA content the process design will be determined by the maximum expected FFA content, which will be also suitable for lower FFA concentrations.