电气石陶粒的制备及其在曝气生物滤池中的应用研究

发布时间：2018-10-13 12:45

【摘要】：污泥是污水处理后的附属品、是一种由有机残片、细菌菌体、无机颗粒、胶体等组成的极其复杂的非均质体。粉煤灰是燃煤电厂排放的固体废弃物,如果处置不当,不仅会对环境造成二次污染,同时也是对资源的严重浪费。目前,我国粉煤灰的主要应用途径是直接作为建筑材料或烧制陶粒用作建筑骨料。污泥处理主要包括卫生填埋、土地利用、焚烧和污泥干化。将废物利用制成的陶粒作为曝气生物滤池进行污水处理成为近年来国内外研究的热点。而且加入电气石的陶粒在污水处理中能有效促进微生物活性,提高反应器启动时间。因此,研究开发污泥掺量大、能够满足曝气生物滤池要求的陶粒势在必行。本文以污泥和粉煤灰为主要原料,添加电气石作为催化剂,经混合、成球、高温烧制等过程制备陶粒滤料,分别考察了烧制温度、恒温时间和原料配比(电气石含量)对陶粒性能的影响,确定了制备陶粒的最佳工艺条件;之后,将按照最佳工艺条件制得的陶粒应用于曝气生物滤池反应器,进行处理生活污水的小试研究,通过考察污染物的去除效果,研究了电气石陶粒滤料在废水生物处理中的应用性能。按照国家标准《水处理人工陶粒滤料》(CJ/T299-2008),以密度、堆积密度、表观密度、比表面积、空隙率、含泥量、盐酸可溶率、破碎率与磨损率之和等为评价陶粒性能的指标,通过单因素试验研究,确定制备电气石陶粒的最佳工艺条件为:烧制温度1050℃,恒温时间10min,原料中污泥含量50%。在最佳工艺条件下制得陶粒的各项指标为:密度2.1273g/cm3,堆积密度0.9886g/cm3,表观密度1.6927g/cm3,比表面积1.6012×104cm2/g,空隙率42.13%,含泥量0.25%,盐酸可溶率1.46%,破碎率与磨损率之和2.96%。制成陶粒表面粗糙,孔隙结构丰富且大孔数量较多,利于微生物的附着生长,是一种优良的微生物载体。将最佳工艺条件下制得的电气石陶粒和对照组用作曝气生物滤池的滤料,处理城市生活污水。反应器采用接种挂膜的方法进行启动,启动时间为8d。分别考察了启动期间和稳定运行期间曝气生物滤池反应器对COD、NH3-N、总磷、SS的去除效果。在启动期间,随着运行时间的延长,反应器出水COD不断减小,去除率逐步升高;出水总磷增大,去除率减小;出水NH3-N浓度减小,去除率升高,之后趋于稳定。最后,对比了电气石陶粒和对照陶粒的物理性能及在废水生物处理中的应用性能。之后对电气石陶粒进行效益分析,利用热电厂废热烧制,节约能源,大大降低成本。分析表明,以污泥、粉煤灰和电气石为原料制备陶粒能够取得良好的经济效益、社会效益和环境效益。
[Abstract]:Sludge is an adjunct after sewage treatment. It is an extremely complex heterogeneous body composed of organic debris, bacteria, inorganic particles, colloids and so on. Fly ash is a solid waste discharged from coal-fired power plants. If it is not disposed properly, it will not only cause secondary pollution to the environment, but also a serious waste of resources. At present, the main application way of fly ash in China is as building material or fired ceramsite as building aggregate. Sludge treatment mainly includes sanitary landfill, land use, incineration and sludge drying. It has become a hot spot in recent years to treat waste water by using ceramsite as biological aerated filter. In addition, the addition of tourmaline ceramsite can effectively promote the microbial activity and improve the start-up time of the reactor in wastewater treatment. Therefore, it is imperative to develop ceramsite which can meet the requirements of biological aerated filter. In this paper, ceramic filter material was prepared from sludge and fly ash with tourmaline as catalyst. The effect of the constant temperature time and the ratio of raw materials (tourmaline content) on the properties of ceramsite was determined, and the optimum process conditions for the preparation of ceramsite were determined. After that, the ceramsite prepared according to the optimum technological conditions was used in the aerated biofilter reactor. The application performance of tourmaline ceramsite filter material in biological treatment of wastewater was studied by investigating the removal effect of pollutants. According to the national standard "Water treatment artificial Ceramsite filter material" (CJ/T299-2008), density, packing density, apparent density, specific surface area, void rate, mud content, hydrochloric acid soluble rate, crushing rate and wear rate are taken as indicators to evaluate the properties of ceramsite. The optimum technological conditions for preparing tourmaline ceramsite were determined by single factor experiment: firing temperature 1050 鈩，

本文编号：2268681