Dynamic conceptual design of industrial processes

Abstract

This paper focuses on chemical process design and layout optimization based on a theoretical approach that takes into account the dynamic feature of price/cost fluctuations. As originally supposed, conceptual and systematic process design consider fixed prices and costs as input data in their models. These models do not account for well-known price and cost fluctuations such as electric energy and crude oil prices. The conventional modeling approach to conceptual design can find a sub-optimal solution because of neglecting the dynamic changes of economic terms within a given time horizon. This manuscript modifies the perspective, and considers the fluctuations of prices and costs within the conceptual design activity, in order to maximize a so-called economic potential. The term fluctuation refers to the deterministic variations of prices and costs while it does not quantify the stochastic oscillations of the market. These oscillations are bound to the mood of investors and require a forecasting approach, which is typical of forms of investment such as the exchange-traded derivatives. A straightforward case study, based on an energy intensive chemical process, shows the benefits and the opportunities of this approach. The mathematical model is based on the implementation of dynamic superstructures, which call for a MINLP formulation. Finally, the manuscript presents and discusses some numerical results and the economic benefits coming from the dynamic approach to conceptual design.