Reliability, availability and maintenance optimisation of heat exchanger networks

A new methodology is proposed to use comprehensive up-to-date commercial software tools for heat exchanger network (HEN) reliability modelling and optimisation. The idea behind this proposal is that to apply the combination of specific HEN optimisation and reliability software packages has several advantages over the commonly used approach. There is a variety of features that need to be taken into account to choose the right software tool. The HEN design has a significant impact on reliability issues and this should be considered. There are many related issues and features – the robustness, the type of welding, the increment of maximum mechanical resistance, the impact on manufacturing costs, reduction of lost opportunity costs caused by exchanger outages, troubleshooting of heating exchanger problems by operators etc. Fouling should be analysed as it has a significant impact on maintenance issues. Up to 30% decrease of maintenance costs can be achieved annually by applying advanced reliability results and determining heat exchanger failure causes. These analyses include the investigation of failure causes, prediction of future probabilities of failures, cleaning planning and scheduling and the calculation of reliability and maintainability.