本文在深入分析燃煤电站CO_2捕获和汽水系统热平衡的基础上,提出一种新型燃煤发电-CO_2捕获-供热一体化系统。该系统通过汽水流程、碳捕获流程及地暖供热流程的有效集成,实现了系统中、低温余热的高效利用,降低了碳捕获对电厂效率的影响。分析结果显示,本文提出的一体化系统,在CO_2回收率90%时,供电效率可达31.32%,供电效率降低8.96%,而传统化学吸收法碳捕获电站效率惩罚普遍在10~12个百分点或更高。同时,该系统可供热350 MW,全厂(火用)效率达34.49%,全厂热效率高达55.88%;该系统以较少的能耗代价实现高效供电、供热与CO_2减排,为燃煤发电机组碳减排提供了独特的学术思路与技术方案。
Based on the analysis of the thermal balance of CO_2 capture system and water-steam system,the paper proposes a new energy system with coal-fired power generation,CO_2 capture and heat supply.The system can make full use of the intermediate and low temperature heat energy and through the integration of steam turbine subsystem,CO_2 capture process and heat supply system. Based on which,the system can alleviate the energy penalty of power plant brought by CO_2 capture and attain the improvement of comprehensive performance.The results show that,the net efficiency of the system can reach 31.32%with 90%CO_2 captured.Its efficiency penalty is only 8.96%,less than the plants with traditional amine CO_2 capture process,whose corresponding number is 10-12%or higher.The system can also achieve a 350MW heat supply,reach 34.49%exergy efficiency and 55.88% total thermal efficiency.Thus,the novel integration system can achieve an excellent comprehensive performance with relatively high-efficiency power generation,large-scale heat supply and low CO_2 emission.And the promising results obtained here will provide a new approach for CO_2 removal with low energy penalty in coal-fired power generation systems.