粉煤灰/污泥烧结陶粒的研制与应用

Development and application of sintered fly ash/sludge ceramic granules

以粉煤灰和工业污水处理站的剩余污泥为主要原材料，采用烧结法研制复合陶粒。分析了不同配方和不同烧结温度对陶粒性能的影响，以陶粒吸水率、容重为评价指标确定最佳配比和最佳烧结温度，并对陶粒用于铺设景观水底、治理城市水体进行了可行性分析。粉煤灰／污泥陶粒的容重为0．79～0.90g／m^3，吸水率为68．95％～80．01％。陶粒对水中氨氮和总磷吸附容量分别为0．03～0．05mg／g和0．01～0．02mg／g。

Fly ash and sludge samples from industry wastewater treatment were used to produce ceramic granules by the sinter method. Effects of fly ash/sludge/clay ratio and sintering temperature on density and water holding capacity of the granules were studied. Using a mixture of fly ash （〉 53%）, sludge （〉35 %） and clay, the ceramic granules （5-10 mm in diameter） produced by 15 min of sintering at 1 000-1 050 ℃, had a bulk density of 0.79- 0.90 g/cm^3 and a water holding capacity of 〉68% by weight. The results of adsorption equilibrium experiments show its capacities for ammonia-nitrogen and the total phosphorus were 0.03-0.05 mg/g and 0.01-0.02 mg/g, respectively. Heavy metal constituents of the fly ash were immobilized in the ceramic granules. The ceramic granules may be used for treatment of slightly contaminated surface water and/or to protect it from pollution by the contaminated bottom sludge which would otherwise be lifted up under current.