煤气化渣对污泥深度脱水性能的影响

Effect of Coal Gasification Slag on Sludge Deep Dewatering Performance

市政污泥深度脱水是一个亟待解决的问题。研究了利用固体废弃物煤气化渣作为骨架构建剂,与市政泥混合进行机械脱水实现以废治废。实验结果表明,添加不同比例的粗渣、筛分渣和改性渣,能有效提高污泥的脱水率,脱水率提高到58.62%~82.01%。脱水效果与煤气化渣的粒径、比表面积、空隙结构和添加量有关。大颗粒会降低脱水效果,而丰富的空隙结构会增加脱水效果。随着添加量的增加,脱水效果经历了平缓、快速增加和饱和三个阶段。最佳添加量分别为污泥绝干量的三倍(筛分渣)和一倍(改性渣)。煤气化渣在污泥中构建了间隙通道和层间通道,提供了刚性支撑,使内部水在压力作用下经脱水通道排出。

Deep dewatering of municipal mud is an urgent problem.Mechanical dewatering of municipal sludge using solid waste coal gasification slag as a skeleton building material was investigated.The results showed that the addition of diferent ratios of coarse slag screened slag and modified slag increased the dewatering rate to 58.62%~82.01%.The dewatering effect depends on the particle size,specific surface area,pore structure,and dosage of slag.Large particles had a negative effect,while an abundant pore structure had a positive effect.As the dosage increased,the dewatering effect went through a plateau,a rapid rise,and a saturation period.The optimal dosage was three times the dry solids of the sludge(screened slag)and twice as much(modified slag).The slag formed interstices and interlayer channels in the sludge,providing rigid support and allowing internal moisture to escape through the dewatering channels under pressure.