基于空气提升原理的清淤系统在塔贝拉水电站库底深水清淤中的应用

Application of Air-lifting Principle Based Dredging System in Reservoir Bottom of Tarbela Hydropower Station

针对塔贝拉水电站四期扩建工程中#4引水洞改建的清淤区域远离库岸、水深大、范围集中、总量少、库底水工建筑物保护要求高等特点,研制了基于空气提升原理的清淤系统,该系统利用高压水流冲射、破碎淤积体,并利用压缩空气形成高压小气泡在清淤管内不断上升、聚合,推动气—液—固三相连动上升,经吸泥管将泥水混合物排放到排泥场,从而达到清淤目的。实际应用结果表明,该系统在2个月内有效清除封堵闸槽顶部和内部的淤积体约8 800m^3,取得了理想的清淤效果,具有显著的综合效益。

Aiming at the characteristics of the dredging area in the alteration construction of No.4diversion tunnel in the 4th extension project of Tarbela hydropower station,such as far away from reservoir bank,large depth,concentrated area,limited volume and vulnerability of the bottom hydraulic structure,a dredging system based the air-lifting principle is invented.The dredging system works in following phases：firstly,water with high pressure is shot to the sediment to break it up;by transporting compressed air to the dredging head,the minute air bubbles will be produced which ascend and merge in the raising pipe,and sequentially causes the gas,liquid,and solid phases moving upwards continuously in the raising pipe;finally,the mixture will be discharged to the specified disposal area.Practical application result shows that the sediment about 8 800m3 on the top and bottom of the gate slot can be removed in 2months by the mentioned system,which is satisfying and demonstrates considerable comprehensive benefits.