粉煤灰提质除杂制备蜂窝陶瓷关键技术与原理研究

This project was conducted to deal with the problems of coal ashutilization such as low utilization efficiency and low added-value of the prepared products. The technological process and fundamental mechanism of the preparation of honeycomb ceramics carrier materials were performed utilizing the coal ash in high-value ways. The key technology and proprietary instruments were developed with the self-owned intellectual property and this supported the resource output efficiency of the coal ash utilization to be improved by more than 30%.. In this project, the composition, structure and properties of the coal ash were systematically investigated, the technologies for impurities removal from the coal ash products were investigated and the key technologies for coal ash dressing were established. Throughtechnological modification, the preparation of the carrier materials of honeycomb cordierite were systemically investigatedusing the coal ash. Furthermore, the active components were loaded on the carrier materials and the novel composite catalyst wereprepared; the property characterizations of these catalyst were performed including the desulfuration,the denitrationand the vehicle exhaustcatalyzing.. In summary through this project, high added-value honeycomb ceramics were developed with the self-owned intellectual property; and this greatly reduced the environmental pollution and realized the efficient and clean utilization of both the energy and resources. This provided technological prototype and demonstration for the high-value utilization of the coal ash resources.

本项目针对粉煤灰资源综合利用效率低、产品附加值较小等问题，开展粉煤灰高值化利用制备蜂窝陶瓷载体制备工艺技术与原理研究，为粉煤灰制备蜂窝陶瓷奠定技术与工艺基础，形成具有自主知识产权的粉煤灰高值利用关键技术。项目系统研究粉煤灰的组成、结构及性能的相互关系，系统研究以粉煤灰等为主要原料，通过各类固废的成分耦合调控以及加工工艺技术调控制备蜂窝堇青石载体材料，并进一步在载体上负载活性组分，获得新型复合催化剂，并进行脱硫、脱硝以及汽车尾气催化性能表征。开发出具有自主知识产权的具有高附加值的蜂窝陶瓷等制品，从而为粉煤灰资源的高值化利用以及制备高性能环境治理材料提供技术基础与技术原型。

中国是煤炭消耗大国，煤炭燃烧后所产生的固体废弃物粉煤灰和气态污染物NOx备受社会关注，其治理也面临迫切压力。针对以上问题开展研究工作，结论如下：.利用纯氧化物、镁橄榄石、镁铝尖晶石和莫来石分别作为原料来系统研究堇青石合成过程中的物相转变，阐明了堇青石的合成机理。.利用固体废弃物粉煤灰与陶瓷抛光废渣为主要原料分别制备了性能优异的发泡陶瓷。通过对粉煤灰、陶瓷抛光废渣成分组成及热性质分析，结合相图与粘度模型预测，系统研究了发泡剂和稳泡剂对其性能的影响规律，结果表明发泡剂碳化硅的最佳添加量为1 wt.%，稳泡剂磷酸钠的最佳添加量为2 wt.%，初步获得发泡陶瓷制备工艺。.利用粉煤灰、石英和菱镁矿粉通过原位固相烧结反应合成堇青石多孔陶瓷，其中粉煤灰添加量为60 wt.%，菱镁矿粉添加量为25 wt.%的样品在1300 °C下烧结2小时后可生成单相的多孔堇青石陶瓷，其具有优异的机械性能和丰富的孔隙结构，其抗折强度为23.92 MPa，抗压强度为72.64 MPa，孔隙率为33.16%，体积密度为1.61 g/cm3，在作为催化剂载体方面具有良好的应用前景。.采用水热法在商用堇青石（CPCC）和粉煤灰制堇青石（SPCC）表面分别负载铈氧化物颗粒（Ce/PCC）作为低温NH3-SCR脱硝催化剂，发现SPCC作为载体的催化剂表面CeOx颗粒的分散性更好、比表面积更大，同时表面具有更多的氧化性物种因而其在较低温度下表现出更好的脱硝性能。.采用水热法在CPCC和SPCC表面分别负载锰氧化物颗粒（Mn/PCC）作为低温NH3-SCR脱硝催化剂，发现SPCC负载的MnOx颗粒为球形并且分布均匀，在CPCC表面的MnOx颗粒相互粘连形成薄层，这种现象同样可能是因为SPCC表面均匀分布的杂质元素作为附着位点促进了MnOx颗粒在其表面的生长，因而表现出更优异的脱硝性能。.本文利用粉煤灰成功制备堇青石催化剂载体，并系统研究了粉煤灰为原料制备多孔材料的工艺技术，采用水热法合成了Ce/SPCC和Mn/SPCC NH3-SCR脱硝催化剂，在低温下取得了优异的脱硝性能，这不仅实现了粉煤灰的高附加值利用，降低了堇青石合成的温度和成本，同时也克服了目前商用催化剂的缺点，具有良好工业应用前景。