Chemical-process design and maintenance optimization under uncertainty: a simultaneous approach

Research work has emphasized the importance of reliability and maintenance in chemical process operation and the benefits from achieving high process availability levels by optimizing the trade-offs between maintenance costs and plant production volumes. This has motivated the need for the development of contemporary techniques and tools for availability assessment of process systems, which go beyond traditional practices, by focussing on the interactions of reliability and maintenance optimization with the detailed process operation and its dynamic, continuously changing environment. Furthermore, at the design stage of chemical plants, operability considerations accounting for the plant´s life cycle, such as flexibility, reliability and maintainability are not typically included. The main reason for this is that there is a lack of an integrated design framework enabling process engineers to look at the various operability factors in conjuction with cost in a systematic and quantified way during process design development. This work presents theoretical and computational developments aiming at the integration of maintenance optimization in optimal life-cycle process design and development under uncertainty. In particular, the impact of uncertainty upon determining the optimal balance between maintenance costs and benefits as well as the interactions of process design and maintainability in the presence of uncertainty are clearly shown and quantified