Systematic retrofit method for refinery hydrogen network with light hydrocarbons recovery

Abstract Retrofit of the refinery hydrogen network is one of the important issues faced by modern refineries. Refinery off-gas streams are rich in hydrogen and valuable light hydrocarbons. Light hydrocarbons recovery (LHR) process can recover the valuable hydrocarbons and generate the hydrogen-rich stream for reuse and recycle. We firstly propose the systematic procedure for the retrofit of refinery hydrogen network integrated with LHR process. The approach combines the pinch analysis technique and process modelling and simulation. The typical pinch analysis technique (i.e. problem table) is used to determine the flowrate targets. Aspen HYSYS is used for the modelling and simulation of LHR process. The retrofit of an industrial refinery hydrogen network is conducted to illustrate the procedure. Results show that the benefit of retrofit scheme (Integrated Scheme 3) with LHR reaches 7.488 million CNY/y, and the investment payback period is only 8 months.