新疆燃煤电厂燃煤副产物的环境地球化学特征及高附加值利用

The Junggar coal basin is a large coal-bearing basin in Xinjiang Uyghur Autonomous Region, Northwest China, with enormous clean coal resources. Due to the increasing energy demand, large amounts of Xinjiang coals will be locally consumed for power generation, coal gasification, and liquefaction, etc, among which power generation accounts for over 50% of the total coal consumption. Meanwhile, large volumes of coal combustion by-products (CCPs), including fly ash, slag and flue gas desulfurization (FGD) gypsum, will be generated from coal fired power plants, which will not only occupy large areas of land, but also may pose potential environmental threat to the land and surroundings by means of leaching. Furthermore, during coal combustion, emissions of gaseous pollutants and particulate matter to the atmosphere may also cause serious environmental problems. This project aims at analyzing the characteristics of the CCPs collected from coal fired power plants in Xinjiang that are mainly fed with the Junggar coals, with special focus on the environmental geochemistry of the trace elements, the enrichment and partitioning of elements during coal combustion and on the leaching potential of the trace elements in the CCPs. Secondly, this project aims to investigate various utilization of the CCPs with high-added values, such as synthesis of zeolites from fly ash, manufacturing of fire-resistant panels from FGD gypsum and fly ash, production of road acoustic barriers using slag; The properties and the optimal producing conditions of the above manufacturing products were determined from the environmental, practical and economic points of view. Finally, this project will investigate the influences of the coal and CCPs characteristics on various applications of the CCPs and optimize the best application of the local CCPs. The research in this project is of high significance for the comprehensive evaluation of coal quality and for rational planning, utilization and sustainable development of the abundant Junggar coal resources; It also provides theoretical methods and feasibility studies for the high value-added utilization of large-scale coal combustion wastes from Xinjiang and other areas of China in the near future.

新疆准噶尔含煤盆地具有丰富的高洁净煤炭资源，随着能源需求的日益增加，越来越多的优质煤炭资源将被大量地用于发电、气化、液化等；其中燃煤电厂发电将产生大量的燃煤副产物（飞灰，炉渣，烟道气脱硫石膏），不仅占用耕地面积，而且可能对耕地和周围环境产生危害；同时，排放的气态污染物也会对环境造成影响。本课题拟对该盆地区内电厂燃煤副产物的各种特征，尤其是微量元素的环境地球化学特征、富集分异特征及燃煤副产物的淋滤性进行研究；在此基础上，对燃煤副产物进行多种高附加值的应用实验研究（如沸石的合成，耐火材料，隔音材料的加工等），分析燃料煤及燃煤副产物的特征对其不同回收利用途径的影响，并从生产技术条件、经济和环境效益等方面进行最优化分析，优选出适合新疆燃煤副产物的高附加值的应用途径。本课题研究对准噶尔丰富的煤炭资源的煤质综合评价和合理开发利用具有重要的指导意义，为今后大规模的燃煤副产物的高效能回收利用提供理论指导。

新疆准噶尔含煤盆地具有丰富的高洁净煤炭资源，随着能源需求的日益增加，越来越多的优质煤炭资源将被大量地用于发电、气化、液化等；其中燃煤电厂发电将产生大量的燃煤副产物（飞灰，炉渣，烟道气脱硫石膏），不仅占用耕地面积，而且可能对耕地和周围环境产生危害；同时，排放的气态污染物也会对环境造成影响。.本项目对该盆地区内两个电厂燃煤副产物的各种特征，尤其是微量元素的环境地球化学特征、富集分异特征及燃煤副产物的淋滤性进行研究，查明燃煤副产物中的有害元素的含量及淋滤性均较低，在燃煤过程中仅有少量的挥发份组分，如As、S、F、Cl、Hg等以气态形式排入大气。在此基础上，本项目利用燃煤副产物成功完成了沸石的合成，耐火板的制备，隔音屏的加工，泡沫玻璃的制备、陶瓷砖体的烧结等多种高附加值的应用实验研究，利用粉煤灰制备的沸石可作为高效的废水处理剂或贫瘠土壤区植物生长的缓释钾肥。制备的粉煤灰/脱硫石膏耐火板具有优良的隔热耐火性能，利用炉渣制备的道路隔音屏具有良好的吸噪性能；制备的泡沫玻璃具有良好的隔热和隔音性能；制备的粉煤灰/煤矸石陶瓷砖体具有优良的机械性能，这些高附加值的应用技术具有良好的应用前景。之后，分析了燃料煤及燃煤副产物的特征对其不同回收利用途径的影响，并从生产技术条件、经济和环境效益等方面进行最优化分析，优选出了适合新疆燃煤副产物的高附加值的应用途径。本项目的研究对准噶尔丰富的煤炭资源的煤质综合评价和合理开发利用具有重要的指导意义，为今后大规模的燃煤副产物的高效能回收利用提供理论指导。