CO_2减排CCS与CCU路线的热力学认识  

Thermodynamics Cognizance of CCS and CCU Routes for CO_2 Emission Reduction

作　　者：朱家骅[1] 郭鑫楠[1] 谢和平[2,3] 夏素兰[1] 梁斌[1] 谢凌志[2,3] 王子宁[1] 

机构地区：[1]四川大学化学工程学院,四川成都610065 [2]四川大学CCUS与C02矿化利用研究中心,四川成都610065 [3]四川大学能源工程安全与灾害力学教育部重点实验室,四川成都610065

出　　处：《四川大学学报（工程科学版）》2013年第5期1-7,共7页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家科技支撑计划资助项目(2013BAC12B01)

摘　　要：基于Gibbs自由能理论提出了以自由能耗散Ω作为CO2减排路线的热力学评价依据,减排的意义在于减少耗散。建立了输出功w与Ω的线性函数关系:w=-1/εΩ/α=-1/(1-β)·Ω/α,参数ε、β、α分别代表自由能耗散比、保留比和不可逆损失。分析计算结果表明,CCS减排路线使自由能耗散增加5.7%且转变为环境负荷,从热力学意义上不可取。CCU减排路线以循环利用为手段,将排放物的自由能转化于再生产品中从而实现自由能回收,降低环境负荷,具有热力学优势。以工业固废磷石膏矿化8×104t/a CO2的实例分析表明,CCU是具有经济效益的CO2减排路线,同时带来可观的资源与环境效益。Based on the Gibbs free energy（ GFE） theory,an indicator of＂Free Energy Dissipation＂Ω is proposed for thermodynamic accessment of route of CO2emission reduction（ CER）. It is pointed out that the value of CER is to reduce the dissipation. A linear function relating power output and the dissipation is derived as,w =-1/εΩ/α=-1/（ 1- β）·Ω/α. where the parameters of ε,β,and αrepresent the ratio of GFE dissipation and reservation as well as the irreversibility. It is revealed,according to the analytic calculation with this function,that the 5. 7% extra GFE dissipation will be added to CCS process then be loaded to the environment. Therefore CCS is not a favorable choice from thermodynamics point of view. Contrarily,originated from CO2 Cycling Utilization,the route of CCU emphasizes converting GFE from industrial wastes into regenerated products,therefore realizes GFE recovery and reduces the environment load. So CCU is advantageous to CCS thermodynamically. It is demonstrated by a case investigation to a project in which 8 × 104t / a of CO2will be mineralized by phosphogypsm,that CCU could be an economic profitable route of CER plus considerable resource and environment benefits.

关 键 词：CO2减排 CCS CCU Gibbs自由能 耗散 

分 类 号：X51[环境科学与工程—环境工程] X7