混合条件对氢氧化镁混凝性能及絮体特性影响

以氢氧化镁作为混凝剂,不同浊度高岭土水样为研究对象,运用iPDA在线监测技术,探求了混合条件对絮体特性和混凝过程的影响;结果表明:快速搅拌转速增大到250 r/min,絮凝效果最好,继续增大,效果变差;随着快速搅拌时间延长到60 s时,絮凝效果逐渐变好,继续延长时间,R值变小絮体细碎;加入超声时,产生的超声振动和冲击力使得絮体被冲击碎,絮凝效果变差;慢速搅拌转速增大至60 r/min时,絮凝效果逐渐变好,再继续延长R值变小。

Effects of Mixing on Magnesium Hydroxide Coagulation Performance and Floc Properties

The coagulation performance and floc properties were investigated using magnesium hydroxide as coagulant under different operational conditions.On-line intelligent Particle Dispersion Analyzer(iPDA) was used to determine the floc characteristics in different turbidity of kaolin water simple.The results show that: the coagulation performance gradually changed for the better when rapid stirring speed reached 250 r/min,prolonged rapid mixing gave poorer performance.Coagulation performance was better when increasing the rapid mix time until 60 s.Continuous increasing the rapid mix time led to a decrease in R value and the final floc size.When adding ultrasound,the resulting of ultrasonic vibration and impact made the flocs broken and led to a poorer performance.The performance gradually changed for the better when slow stirring speed increased to 60 r/min,then R value decreased with increasing the stirring speed.