Objective The aim is to recycle C₃⁺ and H₂ in refinery fuel gas to improve economic benefits.

Methods Through the analysis and comparison of the fuel gas from different sources, the hydrogen-rich and high-level C₃⁺ fuel gas are found out. Then the process of H₂ recycling is optimized and the area of dehydrogenation membrane is increased so as to improve the amount of H₂ recovery. The absorption and stabilization system of catalytic unit and coking unit is used to recover C₃⁺ in fuel gas.

Results The total investment of technological transformation is 3.2 million yuan, this can recover 12.3×10³ tons of C₃⁺ components per year, increase the benefits by 30 million yuan per year, recover H₂ 10.5×10⁶ m³ per year, and reduce the cost of H₂ production by 12 million yuan per year.

Conclusions This scheme makes full use of the existing absorption and stabilization system and the existing dehydrogenation system of the refinery to expand the capacity, it has the advantages of less investment, good benefit and quick efficiency, and great significance for the high-quality development of Yumen Refining and Chemical Plant.