- Make a BFD A plant factory consist of CSTR (RX), flash drum (FD), recycle drum (RD), and distillation column (DC). Reactant feed A and B come in to RX produce C and unwanted product D. Output stream as mixture of C and D from RX is then heat up by HE using steam before come in to FD. Upper stream of FD will be in gas state which will be condensate before coming to RD. Output of RD then recycle back to RX. Bottom stream of FD then continue to DC. Upper output stream of DC being condensate and store at storage drum and then some of it will be as reflux flow and others become product C. Some bottom output stream of DC will be heat up by HE and become gas which will be reflux back. Meanwhile other bottom output become stream of product D