基于聚光光伏余热的燃煤电厂碳捕获系统

Carbon capture system for coal-fired power plantsbased on concentrated photovoltaic waste heat

为响应国家实现碳达峰、碳中和的目标,提出了一种基于聚光光伏余热的燃煤电厂碳捕获系统.该系统是将聚光光伏系统与600 MW燃煤电厂结合,利用光伏余热为碳捕获系统供能.通过模拟与计算可知,利用吸收剂MEA实现90%的CO_(2)捕获率,需在太阳辐照强度为1000 W/m^(2)的工况下,由0.926 km^(2)的聚光光伏电厂为其供能,全年捕集CO_(2)量为1.99䦆Wingdings 2MC@106t.由于光伏组件的废热被带走,光电效率提高4.7%.整个系统中品位较低的热量用于预热锅炉给水,全年可节省4.43䦆Wingdings 2MC@105t的标准煤.热力性分析表明:集成系统的光电效率46.51%,光热效率37.51%、系统热效率54.79%.经济性分析表明:发电成本、CO_(2)回避成本均低于原电厂与抽汽捕碳电厂.该系统为光伏-光热的多级利用以及燃煤电厂的升级改造开拓了新的思路.

In order to meet the national goal of carbon peaking and carbon neutrality,a carbon capture system for coal-fired power plants based on concentrated photovoltaic waste heat is proposed.The system combines a concentrated photovoltaic system with a 600 MW coal-fired power plant,and uses photovoltaic waste heat to power the carbon capture system.Through simulation and calculation,it can be seen that the use of absorbent MEA to achieve 90%CO_(2)capture rate needs to be powered by a 0.926 km^(2)concentrating photovoltaic power plant under the solar irradiation intensity of 1000 W/m^(2),and the annual CO_(2)capture amount is 1.990x0E䦆Wingdings 2MC@0x0F 106 t.As the waste heat of the PV module is carried away,the photoelectric efficiency is increased by 4.7%.The lower grade heat in the whole system is used to preheat the boiler feed water,saving 4.430x0E䦆Wingdings 2MC@0x0F105 t of standard coal per year.The thermal analysis shows that the photoelectric efficiency of the integrated system is 46.51%,the photothermal efficiency is 37.51%,and the system thermal efficiency is 54.79%.Economic analysis shows that the cost of power generation and CO_(2)avoidance are lower than that of the original power plant and the extractive carbon capture power plant.This system opens up a new idea for the multistage utilization of photovoltaic and photoheat and the upgrading of coal-fired power plants.