Scoping and screening complex reaction networks using stochastic optimization

Semantically enabled process synthesis and optimisation

“…The respective evolution of the superstructure, the selected clusters and their maximum objective values are illustrated in Table 8. The results obtained in this work compare well to those obtained in the literature (Marcoulaki, E. C. and Kokossis 1999) and with those obtained by conventional Tabu Search (Table 9). It is apparent that results from Simulated Annealing optimisation offer a small CSTR as the final reactor, which is equivalent to having an extra sub-CSTR at the end of the previous PFR, hence performing the same as a single PFR.…”

“…The1 Van de Vusse reaction consists of a combination of parallel and serial reactions (Kokossis, A. and Floudas 1990;Marcoulaki, E. C. and Kokossis 1999). In this reaction scheme, A is the reactant, B is desired product, and C and D are by-products ( The feed flows at 100 / and contains pure A with the feed concentration of 5.8 / .…”

“…Initially, these were deterministic techniques including non-linear programming (NLP) (Achenie and Biegler 1988) and mixed-integer non-linear programming (MINLP) (Kokossis, A. and Floudas 1990;Raman and Grossmann 1991;Kokossis, A. and Floudas 1994), among others. More recent approaches focus on stochastic search based optimisation with perhaps Simulated Annealing (Marcoulaki, E. and Kokossis 1996;Marcoulaki, E. C. and Kokossis 1999;Mehta and Kokossis 2000;Linke and Kokossis 2003a), Tabu Search (Wang, C et al 1999;Linke and Kokossis 2003b;Cavin et al 2004) and Ant Colony (Dorigo et al 1999;Jayaraman et al 2000;Dorigo and Blum 2005) being the most widely applied. The latest advances in stochastic search based on cascading of population and inflection of solutions is particularly attractive as it provides readily access to optimisation solutions at every stage of the process, the search known as the Cascade Algorithm (Labrador-Darder et al 2009;Kokossis, A et al 2011;Cecelja, F et al 2014).…”

On the use of systems technologies and a systematic approach for the synthesis and the design of future biorefineries

“…Using alternative reactors and better integration, and in reference to a base case stirred-tank reactor, NREL reported a two-fold increase in the concentration of sugars, a ballpark figure for the expected benefits in the yields. Instead of case-by-case analysis, systems tools are able to, systematically target efficiencies (Mehta & Kokossis, 1997Marcoulaki & Kokossis, 1999), setting the scope for integration El-Halwagi, 1997Linke & Kokossis, 2007, El-Halwagi, et al, 2008 and enabling the evaluation of fractionation, enzyme technologies and reactive-separation schemes (Linke & Kokossis, 2003a). …”

“…Such methods are plentiful on energy targeting (Gundersen, 1988;Briones and Kokossis, 1999a,b), water targeting (Wang and Smith, 1994a,b;Smith, 2005;Hallale and Fraser, 1998;Alva-Argaez et al, 1999;2007a,b;Gunaratnam et al, 2005), and mass-exchange networks (Halwagi, 1997(Halwagi, , 1990a(Halwagi, ,b, 2006(Halwagi, , 2008, but also in reactor and reaction engineering targeting (Halwagi and Srinivas, 1992;Marcoulaki and Kokossis, 1999;Kokossis, 1997, 1998;Kokossis and Floudas, 1990), simple and complex distillation Kokossis, 2001, 2002), solvent design (Papadopoulos and Linke, 2006a, b;Kazantzi et al, 2007, Kazantzi andHalwagi, 2005;Kokossis, 2000, 2001) and reaction-separation systems (Linke and Kokossis, 2003a,b, 2004Kokossis and Floudas, 1991). Instead, literature evidence indicates a predominant use of general flowsheeting technology for techno-economic and case-by-case analysis, using Aspen Plus for instance, as in the work of NREL on bioethanol production (Wooley et al, 1999) and that of Haas et al (2006) for biodiesel.…”