废纸造纸污泥陶粒的制备与性能表征

以废纸造纸污泥为原料，辅以集料尾泥(主要成分为粘土)和粉煤灰进行配料，在模拟实际加工工况下制备烧结污泥陶粒，对其微形貌和力学性能进行了表征. 结果表明，当污泥含量高于40%(w)时，有机物氧化释放的热量使高温熔体粘度降低，同时产生的气体压力增大使熔体发胀，从而使陶粒变轻，有明显的降低烧结温度的作用. 当陶粒坯体中含污泥50%(w，干基)、粉煤灰30%(w)、集料尾泥20%(w)时，1140℃烧结后所得陶粒的堆积密度为0.75 g/cm3，盐酸可溶率为0.54%(w)，筒压强度为6.32 MPa.

Preparation and Characterization of Keramzite Spheres Using Sewage Sludge Produced by Waste Paper Recycling

Sewage sludge produced by waste paper recycling was used as principal raw material to sinter lightweight keramzite spheres with gangue sludge and fly ash in the batching. The produced keramzite samples were characterized in terms of their morphology and mechanical properties. It was found that apparent bloating took place at high temperature as the content of sewage sludge was more than 40%(w), at which the oxidation of organics released enough gas and heat to ensure the bloating effect during the sintering process. As a result, the resulting keramzite spheres with the higher strength but lower granule density was sintered at a lower temperature. As the green sample was composed of 50%(w) sewage sludge (in dry state), 30%(w) fly ash, and 20%(w) gangue sludge, the keramzite spheres sintered at 1140℃ had the desirable properties of the granule density at 0.75 g/cm3, the weight loss in hydrochloric acid at 0.54%, and the cylindrical compress strength at 6.32 MPa.