A novel application of exergy analysis: Lean manufacturing tool to improve energy efficiency and flexibility of hydrocarbon processing

This work investigates the techniques used in evaluating distillation structures from lean manufacturing point of view. Oil & gas industry has already started adopting lean manufacturing principles in different types of processes from information flow to processing technologies. Generally, energy costs are the most important factors in processing hydrocarbons. Introducing flexibility desired by lean principles to the system may conflict energy efficiency of the system. However, this does not mean that the economic optimum is the energetic optimum. Therefore all possible changes due to temporarily stopped or not fully utilised plants have to be investigated, resulting in a large amount of cases that have to be evaluated. For evaluation exergy analysis can be used as it involves all energy types, and evaluation is straightforward. In this paper plain distillation structures are investigated, and the boundaries of the systems are set up according to the status of the site. Four component case studies are presented that show that the very same distillation structure can be more or less efficient depending on the status of the industrial site. It is also shown that exergy analysis used with different boundaries on the same system can show flexibility of the system and reveals potentials. (C) 2014 Elsevier Ltd. All rights reserved.