中文摘要：

以天然沸石为主要原料,水泥为粘结剂,发泡聚苯乙烯球形颗粒为内核,经复合、成球、筛分、养护,制备出粒径4~8 mm的免烧球形低密度沸石复合填料。对制备的材料进行了空隙率、表观密度、强度等性能测试。研究结果表明,制备低密度沸石复合填料的最优工艺组合条件为质量百分比沸石∶水泥=75%∶25%,自然条件下养护7~10d,此时制备的成品填料空隙率为47.4%,表观密度为1.23 g/cm3,强度为61.5 N,堆积密度为0.647 g/cm3。扫描电镜图像表明,挂膜前填料表面粗糙,内部存在大量孔隙,挂膜后表面和内部均有大量的微生物附着,与粉煤灰制备的陶粒相比,该填料挂膜微生物量提高了一倍。本研究制备的低密度沸石复合填料,用于在环境温度低于15℃下曝气生物滤池的挂膜启动运行,对氨氮的去除率达到96%,具有较好的氨氮去除效果,表明该复合填料在废水脱氮深度处理方面具有良好的应用前景。

英文摘要：

The unburned spherical low-density zeolite composite paddings 4~8 mm in particle size with natural zeolite as the main raw material,cement as the binder,spherical particles of polystyrene as the core were prepared through the procedure of compounding,sphere making,screening,and maintenance.Based on testing the void fraction,apparent density,compression strength and other characteristics of materials in the preparation,the authors have concluded the optimal conditions of process combination in the preparation of low density composite paddings as follows.Weight proportion of zeolite∶cement is 75%∶25% and maintenance is 7~10 d under normal conditions.Under such conditions,the void fraction is 47.4%,apparent density is 1.23 g/cm3,compression strength is 61.5 N,and piled density is 0.647 g/cm3.Scanning electron microscopy clearly shows that before the biofilm formation the surface is rough,and the interior has numerous pores,whereas after the biofilm formation,a large number of microbes exist on the surface and in the internal.The number of microbes is twice that of the fly ash biological filter.When the method is applied at the ambient temperature below 15℃ under BAF biofilm,the ammonia and nitrogen removal rate of the unburned spherical low-density zeolite composite paddings even reaches 96%.The high ammonia and nitrogen removal efficiency shows a good prospect of the composite paddings in advanced treatment of wastewater denitrification.