燃煤电厂CO_2捕集与系统集成的能耗与水耗分析

Analyses of Energy and Water Consumption for Coal-Fired Power Plant With CO_2 Capture and System Integration

CO_2捕集是目前降低电厂CO_2排放最直接有效的方法之一,但能耗过高成为限制其发展的最大障碍,同时水耗的增加也对现有电厂的集成带来了挑战,本文从CO_2捕集系统与电厂系统的集成角度出发,建立了集成系统的能耗与水耗模型,结合典型300 MW亚临界燃煤发电机组参数,分析了CO_2捕集对电厂的影响,考察了CO_2捕集系统的运行参数对集成系统能耗与水耗的变化关系。结果表明,集成CO_2捕集后电厂发电效率降低了近10个百分点,冷却循环水用量与总水耗增加了近25%,单位发电量冷却循环水量与水耗增加了70%以上,同时系统能耗与水耗随CO_2捕集参数的变化而呈现不同的变化趋势。

CO2 capture is one of the most direct and efficient way of reducing CO2 emissionsfrom coal-fired power plant. However, high energy penalty is the main obstacle of limiting its development, and the increased water consumption brings huge challenges for retrofitted plant. A model of energy and water consumption of the integrated system is established with a typical of 300 MW subcritical coal-fired power plant. System performance is conducted by investigating the impacts of CO2 capture on power plant, and the effects of operation parameters of CO2 capture on energy consumption and water consumption. Results show that power generation efficiency of the integrated system drops off nearly 10%, the amount of circulating cooling water and water consumption increases nearly 25%, while the specific cooling water and water consumption increase by more than 70%. Meanwhile, energy consumption and water consumption with the changes of CO2 capture parameters present different trends.