Abstract: Distillation of oleoresin was studied,using Claisen flask as still and CO2 or N2 as circulating gas.Factors such as flow capacity of circulating gas,distillation pressure,end distillation temperature,temperature of circulating gas,and kinds of gas which influence the distillation of oleoresin were investigated.The results showed that optimum technological conditions of distillation of pine gum for producing 1 kg rosin were as follows:flow rate of CO2(0.140-0.160 m3/h),distillation pressure 12.67 kPa,end temperature of distillation 185-190℃.The effects of temperature and kinds of circulating gas on distillation of oleoresin were insignificant.Since boiling point and content of distillate components are different,operation sequences of flow rate of CO2 at(0.100-0.160 m3/h) and distillation temperature at 80-185℃ were preferable.According to the experimental results,a technological flow diagram has been designed.Since no phase change occurs during circulating gas distillation,heat for phase change of overheated steam in traditional process has been saved.Compared with direct steam method,the consumptions of energy and cooling water by this method were decreased by 1.663-2.034 GJ and 7.986-9.762 m3 respectively.Separator for oil from water,filter for salt and large boiler for producing overheated steam were not required to be built.Water was not contaminated in products manufactured by this method.The rosin shows no crystallanity,turpentine is transparent without turbidity,and no wastes are produced.