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DOE OSTI · 1533672

A superstructure-based framework for bio-separation network synthesis

Wu, Wenzhao·Yenkie, Kirti·Maravelias, Christos T.
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Abstract

Modern biotechnologies enable the production of chemicals using engineered microorganisms. However, the cost of downstream recovery and purification steps is high, which means that the feasibility of bio-based chemicals production depends heavily on the synthesis of cost-effective separation networks. To this end, we develop a superstructure-based framework for bio-separation network synthesis. Based on general separation principles and insights obtained from industrial processes for specific products, we first identify four separation stages: cell treatment, product phase isolation, concentration and purification, and refinement. For each stage, we systematically implement a set of connectivity rules to develop stage-superstructures, all of which are then integrated to generate a general superstructure that accounts for all types of chemicals that can be produced using microorganisms. Here we further develop a superstructure reduction method to solve specific instances, based on product attributes, technology availability, case-specific considerations, and final product stream specifications. A general optimization model, including short-cut models for all technologies, is formulated. The proposed framework enables preliminary synthesis and analysis of bio-separation networks, and thus estimation of separation costs.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYglobal optimizationmixed integer nonlinear programingprocess optimizationrenewable chemicals

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Wu, Wenzhao, Yenkie, Kirti, Maravelias, Christos T.. 2016-10-27. A superstructure-based framework for bio-separation network synthesis. https://doi.org/10.1016/j.compchemeng.2016.10.007

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