调质剂对河道淤泥泥水分离性的影响

Influence of Conditioning Agent on Slurry Separation of Silt in River Channel

河湖疏浚工程中,河道淤泥泥水分离技术的发展要点在于减少运量,降低成本和避免二次污染,因此如何增强淤泥的泥水分离性能至关重要。淤泥泥水分离性由淤泥流动性反映,淤泥流动性又由坍落度直径来表征。初步选取常见的几种絮凝剂分别对河道淤泥进行絮凝试验,结果显示阴离子生物试剂、硅酸盐水泥、石灰、硫铝酸盐水泥、PAM试剂能显著降低淤泥的流动性,其中石灰的絮凝效果最优。70%含水率下,500 g长江南京段淤泥中投加5 g石灰对比空白组的坍落度直径下降了68%。在复配试验中,选用石灰分别复配阴离子生物试剂、硅酸盐水泥、硫铝酸盐水泥和PAM试剂进行絮凝试验,发现投加5 g石灰和3 m L阴离子试剂并静置3 h的综合絮凝效果最佳,降低淤泥流动性的效果最优,其坍落度直径相比空白组下降了78%,从而能起到有效提高河道淤泥泥水分离性的作用,为河道淤泥的流动性能研究开展探索工作。

In the lake river dredging project,the key of the development of river sludge dewatering technology is to reduce the volume,reduce costs and avoid secondary pollution.Therefore,how to enhance the performance of slurry separation is very important.Mud slurry separation from silt liquidity reflects the silt liquidity slump by diameter characterization,several kinds of common flocculants were selected to carry out flocculation tests on the river silt,the results showed that anion biological reagent,Portland cement,lime,sulphoaluminate cement,PAM reagent can significantly reduce the liquidity of silt,the flocculation effect of lime and the optimal moisture content,compared with the blank group,the slump diameter of the 500 g silt in the Nanjing section of the Yangtze River decreased 68%with the addition of 5 g lime under the water content of 70%.In the mixed experiment,using lime respectively mixed anionic biological reagents,Portland cement,sulphoaluminate cement and PAM reagent flocculation test,it was found that the comprehensive effect of flocculation adding 5 g lime and 3 mL anion reagent and static 3 h,reduce the silt liquidity optimal effect,the slump diameter decreased by 78%compared with the blank group,thus can effectively improve the river silt slurry separation effect,so that to carry out the exploration work for the research of the flow properties of river silt.