摘要
为了研究滩涂淤泥电渗效率,根据相似原理建立室内模型,并在等电势梯度条件下进行试验.试验过程中采集排水量、通电电流和电势数据,研究了电渗能耗、电势利用率与电极间距的关系.基于有效电势原理对电渗能耗系数和处理时间进行了分析,采用简易算例对不同工况下的电势利用率和能耗系数进行了讨论.结果表明,等电势梯度下,电渗前期能耗系数随电极间距缩短而线性下降,电极间距缩短至12 cm时能耗系数降至0.54 W·h/m L.电极间距越小,相同排水效果所需的处理时间越短.提高界面电阻会降低电渗排水速率,但不影响电渗能耗系数.建议在工程中选取新型电动土工合成材料以及合理的电极布置形式,以提高电渗效率和经济性.
To study the electro-osmosis efficiency of marine sludge,laboratory models were set up according to the similitude principle and tests were conducted under constant potential gradient. During the experimental process,the water discharge,the apparent current and the potential were measured. The relationship of the electro-osmotic energy consumption,the potential use ratio and the electrode spacing were studied. The electro-osmotic energy consumption coefficient and the treating time were analyzed based on the effective potential principle. A simple example was adopted to discuss the potential use ratio and the energy consumption coefficient under different working conditions. The results show that the energy consumption coefficient decreases linearly with the decrease of the electrode spacing in the early stage of electro-osmosis under constant potential gradient. The energy consumption coefficient drops to 0. 54 W · h/m L when the electrode spacing decreases to12 cm. The shorter the electrode spacing,the less the treating time for the equal dew atering effect.The increase of the interface electric resistance can reduce the electro-osmotic drainage rate,but does not affect the electro-osmotic energy consumption coefficient. It is recommended to select new types of electro-kinetic geosynthetics and appropriate electrode arrangements to improve the electro-osmosis efficiency and economy.
引文
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