污水污泥页岩陶粒的烧成工艺与性能

Calcining process and performance of expanded shale made from shale and sewage sludge

为制定合理的污水污泥页岩陶粒烧成工艺及揭示污水污泥对陶粒性能的影响,研究了污水污泥掺量对陶粒烧胀性能的影响以及预热、焙烧的温度和时间等因素对陶粒性能的影响,采用扫描电镜观察了污水污泥和烧成工艺对陶粒结构的影响.结果显示,含水率80%左右的污水污泥掺量30%时,可获得表观密度700 kg/m3左右的轻质陶粒;适当降低预热温度、缩短预热时间、提高焙烧温度和延长焙烧时间有利于获得轻质污泥页岩陶粒.掺加污水污泥有利于页岩陶粒烧胀性能提高,但需要控制合适的烧成工艺.

To establish the reasonable calcining process of expanded shale with sewage sludge and to reveal the influence of sewage sludge on the performance of the expanded shale,the influence of sludge content on the expansibility of expanded shale when calcined and the influence of calcining temperature and calcining duration on the performance of expanded shale were investigated experimentally.The interior structure of expanded shale was observed using a electron microscope.It is shown that the expanded shale with apparent particle density of 700 kg/m^3 was obtained when the content of sludge with 80% moisture content reached 30%,and that low preheating temperature,short preheating duration,high calcining temperature and long calcining duration would be helpful to get a light-weight expanded shale with sewage sludge.It is suggested that the addition of sludge is beneficial to the expansibility of expanded shale,while the temperature and duration should be controlled properly