LAUSR

The operation pressure levels of refinery hydrogenation units (e.g., hydrocrackers and hydro-treaters) and hydrogen supply units (i.e., hydrogen plant and continuous catalyst reforming unit) are normally different. The hydrogen compressors (i.e., make-up hydrogen and recycle hydrogen compressors) are widely utilized to raise the pressure of the hydrogen-rich streams. The valves are also used to reduce the pressure of hydrogen-rich streams, and this leads to the waste of power. Hydrogen turbines have been successfully applied in practical industrial plants to recover power. This paper presents a novel superstructure of refinery hydrogen networks integrated with hydrogen turbines to recovery the power. The superstructure consists of a hydrogen production plant, a continuous catalyst reforming unit, other hydrogen sources and sinks, hydrogen compressors and turbines. The mathematical model including mass balance and logical constraints is proposed, with the objectives of minimizing flowrate of hydrogen utility and minimizing the difference between consumed power in compressors and recovered power using turbines. A simplified industrial case study is solved to illustrate the proposed methodology. Results show that 1 MW of power can be recovered via the integrated turbines.