燃煤电厂烟气污染物协同控制过程多环芳烃的赋存特征和迁移转化机理研究

This project aims to conduct the mechanistic study on PAHs occurrence and transformation behavior during the cooperative control of pollutants in flue gases generated by coal-fired power plants of Anhui province, China. Particles of different sizes and gaseous PAHs in flue gases at the inlet and outlet of air pollution control devices including flue gas denitration, dust precipitator and desulfurization will be collected. Sophisticated instrumental and chemical analyses of these samples will be performed. Obtained experimental results will be interpreted in the framework of environmental chemistry, coal chemistry, analytical chemistry and environmental geochemistry. First, the characteristic composition, occurrence and distribution of PAHs will be investigated, along with the partition behavior between inhalable and gaseous PAHs in flue gases. Moreover, thermodynamic experiment will be carried out to further investigate the effect of temperature variation due to flue gas cooling process and material exchange due to wet flue gas desulfurization process on the PAH transformation. Finally, the general transformation modes of PAHs during flue gas denitration, electrostatic precipitator and desulfurization will be constructed. In summary, this study would be beneficial in developing the environmental geochemistry theory about the PAH cooperative control in coal-fired power plants.

本课题拟以安徽省典型燃煤电厂作为研究对象，重点针对脱销、除尘和脱硫设施前后以及烟囱烟气中颗粒态（粗颗粒、细颗粒和超细颗粒）和气态多环芳烃（PAHs），利用高精密仪器分析，将环境化学、煤化学、分析化学、环境地球化学理论相结合，查明烟气中PAHs的种类、含量、赋存形态和分布特征；揭示污染物协同控制过程中烟气PAHs在可吸入颗粒态和气态中的分配规律；继而结合室内热力学实验及PAHs稳定碳同位素分馏机理的研究，解析烟气降温过程温度驱动作用和湿法脱硫过程物质交换作用对PAHs演化行为的影响机制，进而建立烟气脱硝---除尘---脱硫系列过程PAHs的演化模式，以丰富和发展燃煤电厂烟气污染物协同控制过程PAHs的环境地球化学理论。

对燃煤电厂排放多环芳烃的赋存和演化规律的研究，对于控制并预测燃煤电厂PM10、PM2.5和多环芳烃的排放、发展洁净煤利用技术、以及制定相应的环保法规都具有非常重要和实际的意义。.本研究拟以安徽省燃煤电厂作为研究对象，通过对电厂脱污装置前后烟气以及除尘器各电场飞灰的采集与分析，采用环境地球化学新方法和多手段相结合，探寻了多环芳烃在燃煤过程中的排放特征和赋存规律，分析了烟气传输和静电除尘过程的物理化学作用与多环芳烃自身性质间的响应关系，探讨了该过程下多环芳烃的演化规律。在此基础上，进一步明确了电厂燃煤排放多环芳烃的成分谱轮廓图，从而丰富和发展了燃煤电厂可吸入颗粒物中的多环芳烃的排放和控制过程中的环境地球化学理论。