Abstract: The energy-use state was analyzed on the heat pump process in a 0.6 Mt/a light-ends unit with the process simulation software PRO/II. The pinch point technique was used to optimize the parameters of the heat-exchange system drived by heat-pump and the energy efficiency of some key equipment was also calculated. The majorization induced favorable energy saving effects and resulted in saving heating and cooling as high as 712.29 kW and 712.29 kW, respectively.