Complete superstructure framework for biorefineries

August 10, 2015

Complete superstructure framework

We have developed a complete superstructure framework, utilising Simulated Annealing algorithm, a generic probabilistic metaheuristic global optimization method, on FORTRAN programming language, for the full conceptual design and optimisation of different integrated innovative biorefinery processes. One of the subtopics that we are working on is the examination of the impact of different mass transfer correlations on the real design of bio-reactors running different biorefineries examples based on recently developed or under research technologies using the simulated annealing (SA) code embedded with appropriate mass transfer correlations for the best approximation of mass transfer between phases with in the bioreactors.

The synthesis framework which includes (1) the Targeting stage (creation of initial structure of the superstructure representation using the shadow reactor superstructure), (2) the Screening and design stage (evaluation of the results of the targeting stage and screening of the options that have a positive impact on the system), and (3) the Analysis stage and validation, is the implementation of a generic probabilistic metaheuristic global optimization method, employing evolutionary optimisation utilising Simulated Annealing (SA) algorithm, for the synthesis, design, optimization and superstructure representation of complex network reaction systems.

The great importance of the framework is that it identifies the maximum achievable efficiency of the resulting optimum reactor network, providing useful information about: (1) The number and type of reactors, (2) The desired mass transfer correlation for each type of reactor, (3) The volumes of reactors, (4) The appropriate feeding, mixing, recycling and bypassing strategy and (4 )The optimal values of the flowrates, compositions and yields.

Further development of the SA code which firstly developed by Kokossis and Floudas (1990) for the synthesis, design and optimisation of multiphase chemical and biochemical processes, includes the creation of a mass transfer library and is continuous enhancement for the automated selection of the appropriate mass transfer correlation according to the reactor/bioreactor configuration, the construction a link between the SA code and Aspen for more accurate property calculation using CAPE OPEN and on the creation of an interface to automate the framework to enable the user the fast and easy input of reaction equations and kinetics and the feed re-characterization.