石灰、石膏及混合絮凝剂对钻孔废弃泥浆压滤脱水性能的影响

摘要

In this paper, drilling clay slurry is used for study, and lime and gypsum are selected as flocculent. Test method of first flocculation then pressure filtration was used to study the rule using the two flocculents alone and then together under different dosages. Results show that the slurry pressure filtration dewatering rule of lime and gypsum increases non-linearly. When a single flocculant is added, the slurry pressure filtration dewatering rate increases with the increase of the amount of flocculent dosing. there is an optimal dosage of gypsum flocculent. When a mix of flocculants are added, the amount of lime flocculant has a great impact on the slurry pressure filtration dewatering rate, the change of lime flocculant dosing has lesser influence on the dewatering rate when the dosage is smaller than the optimal value. When the dosage is larger than the optimal value, the dewatering effect of lime flocculent is better than gypsum flocculent under the same conditions. Finally, a slurry dewatering mathematical model of both the optimal dosage is established. The findings provide important guidance for slurry solid-liquid separation in engineering.%以钻孔粘土废弃泥浆为研究对象，选用石灰和石膏作为絮凝剂，采用先单一、后混合添加的方法，按照先絮凝、后压滤的试验步骤，研究不同加药量时，石灰、石膏两种絮凝剂单独使用以及不同配合比时，絮凝剂对钻孔粘土废弃泥浆絮凝脱水的规律。试验结果表明，添加石灰和石膏絮凝剂后，泥浆压滤脱水规律呈非线性增长。添加单一絮凝剂时，泥浆压滤脱水速率随加絮凝剂加药量的增加而增大，存在最优加药量；添加混合絮凝剂时，石灰絮凝剂加药量的变化对泥浆压滤脱水具有较大的影响；当石灰絮凝剂加药量未达到最优时，石膏絮凝剂加药量的变化对泥浆压滤脱水影响较小，当石灰絮凝剂加药量达到最优后，石膏絮凝剂加药量变化对泥浆压滤脱水影响较大。并建立两者添加方式最优加药量时泥浆脱水数学模型。研究结果为工程中泥浆固液分离提供重要指导。