Integrated methodology for optimal synthesis of lignocellulosic biomass-to-liquid fuel production processes: 2. Superstructure MINLP modeling and evaluation for optimal biofuel process synthesis and integration

For thermochemical conversion routes to BtL fuel production, in part 1, we have developed a framework for the synthesis of a BtL superstructure that was formulated by the interconnection of processing blocks consisting of unit operations belonging to five base case process routes along with the data and information prepared for the embedded processing blocks. In part 2, a mixed integer nonlinear programming (MINLP) model is implemented for the superstructure optimization. The superstructure is defined as an MINLP problem coded in GAMS 24.5.6, which sets the objective to minimize the total cost of manufacturing (TCOM) of BtL fuels under different cases and integration scenarios. Three cases are demonstrated for three different product profiles, and three network flowsheets are obtained as optimal technology routes. The three optimal network flowsheets are then rigorously simulated and compared with the base case process flowsheets. The results demonstrated that this methodology can generate optimal BtL biofuel production processes under different product scenarios.