Multi-site utility integration - an industrial case study

Mitsubishi Kasei and Mitsubishi Petrochemical merged to become Mitsubishi Chemical in 1994 making it the largest chemical company in Japan. This created an opportunity for improving their production systems especially for those production sites that are physically built next to each other. Mitsubishi Yokkaichi production site is a typical example, which consisted of three production sites in the old company structure. Each production sites consisted of a utility plant producing steam and electricity for their production. Changes have been made since the merge such as connecting steam and electricity between the plant sites for better flexibility, efficiency as well as capacity of the utility system. Beside these, there remain many other alternatives for further improvement. To explore these opportunities, a site-model were developed which consists of the three utility plants and production units. In this paper, applications on Mitsubishi Yokkaichi production site are presented to illustrate the features of the sitemodel.