低浓度疏浚淤泥透气真空泥水分离模型试验研究

基于高含水率疏浚淤泥堆场透气真空快速泥水分离方法的专利,设计研制了大型透气真空模型装置。对含水量高达液限3倍以上的疏浚淤泥进行了泥水分离试验研究。结果表明:透气真空技术能够使高含水量淤泥实现快速泥水分离,只需10d时间,淤泥的体积可以减少三成以上,连续抽水一个月左右时的淤泥泥面沉降的应变速率仍达3%/d。基于模型试验结果,还分析了淤泥平均含水量、淤泥泥面沉降速率、尾水悬浮物浓度的变化规律,发现沉降速率与淤泥平均含水量密切相关,尾水悬浮物浓度远低于规范规定的一级排放标准值。

Large-scale model tests on dewater of dredged clay by use of ventilating vacuum method

A large-scale model equipment was designed and made for dredged clays dewatering with ventilating vacuum method. Dewatering tests were performed on the dredged clays with initial water content being above 3 times liquid limit. The testing results showed that the volume of dredged clays can be decreased by over 30 percent with ventilating vacuum method for dewatering of 10 days, and the volume strain rate of dredged clays at the model still reaches about 3%/day when dewatering continues for one month. This paper also investigated the change law on the average water content and the deformation rate of dredged clays, as well as the suspended solids concentration of separated water from dredged clays. It was found that deformation rate has a good linear relationship with average water content, and the suspended solid concentration is very low.