超声声能密度对净水厂污泥脱水性能的影响

Effect of ultrasound energy density on dewaterability of drinking water treatment sludge

考察了不同声能密度(0.03,1.0,3.0,5.0W/m L)时超声作用对净水厂污泥脱水性能的影响,明确了污泥脱水性能变化的影响因素.结果表明,较低声能密度(0.03,1.0W/m L)超声作用少于10min时,污泥脱水性能可改善;而高声能密度条件下,无论超声时间长短,污泥的脱水性能均恶化.声能密度越高,污泥上清液中溶出有机物越高,絮体特性变化越明显,污泥脱水性能恶化程度越显著.在较低声能密度时,污泥的脱水性能与溶出有机物和污泥絮体特性变化无关;而在高声能密度(5.0W/m L)时,脱水性能的恶化程度与溶出有机物和絮体Zeta电位密切相关.

The influence of ultrasound energy densities on dewaterability of drinking water treatment sludge and the involved influencing factors was investigated. The dewaterability of sonicated sludge was improved at relatively low energy densities of 0.03 and 1.0W/m L in less than 10 minutes. However, at relatively high energy densities, the dewaterability of sludge was deteriorated regardless of ultra-sonication time. The content of solubilized organic matter in the supernatant of sonicated sludge was increased. Additionally, the floc characteristics changed obviously and the dewaterability got worse as the energy density increased. At lower energy densities of 0.03 and 1.0W/m L, the dewaterability of sludge was not correlated with solubilized organic matters and floc characteristics of sonicated sludge. However, at a high energy density of 5W/m L, the dewaterability was significantly related to solubilized organic matters and Zeta potential of sludge.