As PetroChina Yunnan refinery started the production, the vapour recovery system, which was designed and manufactured by HYTEC-MT, also put into operation. The vapour recovery system consists of VRU and vapour holder and the capacity is 4000 Nm3/h. The designed emission standard is the concentration of NMHC < 120 mg/m3 and the concentration of benzene < 0.012 g/m3. The analytical report which was tested and written by PetroChina Yunnan refinery stated that: the concentration of NMHC is small than 30 mg/m3, and the concentration of benzene is small than 0.012 g/m3.