(472f) Comparative Study for Evaluation of Thermal Integration Projects Based on Pinch Technology

Thermal integration in chemical processes has proved to be an effective alternative, given the continuous pressure imposed by regulatory standards. Additionally, it is well-known that the consumption of thermal energy in the industry contributes to a significant fraction of CO2 emissions and other greenhouse gasses. Moreover, the correlation between the rising energy prices and potential carbon/energy taxes invariably leads to higher operating costs¹. However, process stream calorific potentials can be applied to reduce the use of utilities and fuels, resulting in lower emissions, residues, and operational costs.

Pinch analysis has proven to be a successful solution for reducing energy consumption in numerous industries worldwide. The knowledge about this technique has expanded far beyond the original studies and has become a consolidated part of the global strategy for process design optimization and associated advances². By evaluating the hot and cold process streams, a deliberative trade-off between operating and capital costs is taken into account to obtain the minimum total cost in a heat-exchanger network (HEN)³. Such an approach allows the definition of requirements for heating and cooling based on a deep understanding of the process from an energy perspective.

Although some commercial process simulators automate the calculation procedures related to Pinch technology (such as HYSIM®, HEXTRAN®, and Aspen Energy Analyzer®), these tools demand a high acquisition cost, being a possible limiting factor for their disseminated use by the scientific and engineering communities. Motivated by this, this research evaluates the potential of the Heat-Exchanger Network Synthesis Analysis and Design (HENSAD) software as an open-access tool based on Pinch analysis for establishing energy and economic targets, in addition to the cost estimation for heat exchanger networks.

For this purpose, the software infrastructure is established upon the data provided by a real-time acquisition system (PI System - AVEVA/OSIsoft) through an integrated platform with process simulators (Aspen Plus, Unisim, or DynSim) and pre-treatment of thermodynamic data to quantify the heat potential of process stream fractions developed in Python. A comparative study is performed to validate the results generated by the Aspen Energy Analyzer (AspenTech) and HENSAD. Such evaluations show the effectiveness of HENSAD to provide valuable economic analysis.

References

¹ Olsen, D., Abdelouadoud, Y., Liem, P., Welling, B. The Role of Pinch Analysis for Industrial ORC Integration. Energy Procedia, v. 129, p. 13-15, 2017.

² Kemp, I. C. Pinch Analysis and Process Integration: A user Guide on Process Integration for the Efficient Use of Energy. 2. Ed. Elsevier, 2007.

³ Turton, R., Bailie, R. C., Whiting W. B., Shaeiwitz J. A. Analysis, Synthesis, and Design of Chemical Processes. 4. Ed. Prentice Hall, 2012.