炼油厂低温余热发电技术及其经济性分析

Technologies of electric power generation by low-temperature waste heat in refinery

随着原油价格的上涨及国家对"低碳经济"要求的深入,炼油厂低温余热的回收利用研究已成为重要的方向之一。在分析炼油厂工艺装置低温余热的分布和特点的基础上,提出在余热直接利用基础上的间接利用方式——余热发电。并以某南方炼油厂为例,对其两种热力学效率和经济性进行了分析,结果是低温余热发电的效率可达40%,基本与普通的火力发电厂相当;对于低温余热剩余较多的炼油厂(特别是南方炼油厂),与低温余热同级利用相结合的发电方案的经济性较好。

With the rise in crude oil price and ＂low carbon economy＂ required by the government,the recovery and utilization of low low-temperature waste heat in oil refinery has become one of important R D aspects in petrochemical industry.On the basis of the distribution and characteristics of low-temperature waste heat in refinery process units,an indirect utilization technology based upon the direct utilization of waste heat—electric power generation by low-temperature waste heat is proposed,and economics are analyzed.The thermal efficiency,enthalpy efficiency and economics of the electric power generation system using low-temperature waste heat are studied through a case study of a refinery in south China.The results show that the enthalpy efficiency should be applied in energy recovery evaluation of this system,and the enthalpy efficiency of electric power generation system using low-temperature waste heat is as high as 40%,which is close to that of thermal power plant.For the refinery with higher amount of low-temperature waste heat,the integrated low-temperature waste heat electric power generation offers good economics.