Refinery hydrogen management

Nowadays, refineries face a double challenge: increasing hydrogen consumption for deeper hydrotreating, together with stricter environmental legislation on the sulfur content of fuels, which further increases refinery hydrogen demand. Therefore,hydrogen system is bottlenecked and hence hydrogen management has become a priority issue in current refinery operations. Pinch Analysis is a powerful tool for targeting minimum hydrogen utility in refinery hydrogen network and establishing improvement directions. The concept of hydrogen surplus is not only used to identify the bottlenecks in the hydrogen distribution system, but also provides valuable theoretical insights into the impact of hydrogen purification on the performance of a hydrogen distribution network. In this thesis, hydrogen pinch methodology has been successfully applied to a refinery hydrogen distribution network. Both low cost and capital investment solutions have been developed to improve the hydrogen network efficiency. Moreover, the low cost solutions delivered significant potential benefit to site and will be implemented in September 2004. In addition to the pinch analysis for deciding improvement solutions, hydrogen management requires further tools for system representation. A shortcut method has been successfully applied and a deterministic steady-state lumped model has been developed for simulating the behaviors of hydrogen distribution system and predicting the impact of network modifications on the individual network elements, as well as the network constraints. Besides delivering improvements to the site, the hydrogen system requires support for sustaining performance. Sensitivity analysis and pinch based solutions (operating strategies) have been developed for sustaining performance of hydrogen distribution network. Finally, A systematic approach has been developed for hydrogen management studies,based on experiences with a case study.Chemical TechnologyApplied Science