Comparative study of energy saving potential for heavy chemical complex by area-wide approach

The thought of single site approach for energy saving in a site has been evolved to that of area-wide approach which considers multiple sites together as if they were a single entity. In area-wide approach, R-curve analysis plays an important part to evaluate the energy efficiency of the site utility system for utilizing high temperature heat, which is possible to identify energy saving potential and understand the characteristics of the utility system. R-curve analysis was applied to Mizushima complex, one of the ten largest heavy chemical complexes in Japan, and identified the characteristics and the energy saving potential for the whole of the complex. In area-wide approach, low-grade heat utilization for energy saving is also important. Total site profile analysis was used to evaluate the possibility of low-grade heat utilization. Mizushima complex was evaluated for the characterization by comparison of its energy saving potential to that of another heavy chemical complex, Chiba. It was found that the energy saving potential of Mizushima complex was twice in R-curve analysis than that of Chiba complex. This meant that the equipment in the utility system in Mizushima complex performed less efficiency than that in Chiba complex.