Constructed wetlands (CWs) have been used in wastewater treatment. To understand the characteristic and the dynamics of the recovery of different clogging types for virtual-flow constructed wetland (VFCW), three vertical flow constructed wetlands (VFCW), fed glucose solution (bed1), starch suspension with (bed2) and without bacteriostat (bed3) were used to simulate different types clogging (clogging caused by biofilm, insoluble organic matter, and inert organic matter). The hydraulic conductivity and porosity of three VFCWs were measured regularly during the resting operation. The results indicated that the clogging caused by biofilm and organic matters can be recovered through applying resting operation. After resting for 15 days, the hydraulic conductivity recovery rate of the upper layer for bed 1 reached 500-600, and its hydraulic conductivity stabilized at 0.65cm/s. The recovery rate of lower layer (Q3, Q4 and Q5) decreased due to its higher initial value of hydraulic conductivity. The change of porosity had the same rulers. The main reason of clogging recovery of bed 1 were as follows: 1) the EPS was decreased, which made the biofilm became small and dispersive; 2) microorganisms enter an endogenous respiration state due to the short of nutrients, and endogenous respiration involves consumption of cell-internal substrate, which led to a loss of activity and slightly reduced biomass. Thus, the recovery dynamic can be deduced based on the rule of endogenous respiration rate. The result showed that the theoretical value and the measured value were in good agreement. For bed 2, the hydraulic conductivity increased greatly in the first 20 days of resting operation, and then stabilized at 1.2 cm/s. its recovery rate was more than 3000. Similarly, the hydraulic conductivity recovery rates of Q3, Q4 and Q5 decreased gradually. After the resting operation, the porosity of Q1, Q2 and Q3 increased greatly, and it reached 20%, 29%, 96% of the initial porosity. The porosity recovery rate reached 77%, 80%, 96% respectively. During the resting operation, the trapped particles were decayed in a humid environment, and the porosity of bed 2 increased greatly during the first 12 days resting. After later resting operation, with organic particles decay, the particles' bridging collapsed, which made the hydraulic conductivity of bed 2 increased greatly. Therefore, based on the organic compound biodegradation, its hydraulic conductivity recovery dynamics can be deduced. The result showed that the theoretical value and the measured value were in good agreement. The recovery of clogging caused by biofilm and organic matters respectively can be complete basically after resting operation for 9 and 20 days, respectively. The recovery of clogging caused by biofilm was much faster than that of clogging caused by insoluble organic matters. In the actual operation, the resting time should be considered according to the target of recovery rate and the condition of continuum running. On the other hand, it was also found that the clogging caused by inert particles can't be recovered through applying resting operation, which implies that clogging by inert particles is difficult to recover through applying resting operation.%人工湿地是一种常见的污水处理技术,但一直受到不可避免的堵塞问题的困扰.该研究主要以不同堵塞现象下的垂直流人工湿地模型为对象(可溶性有机物堵塞,不溶性有机物堵塞,加入抑菌剂的不溶性有机物堵塞),在轮休操作下持续测量不同时期孔隙率与渗透系数变化情况,研究3种堵塞类型的恢复规律,并对其动力学进行分析.试验结果表明在相同轮休期下,生物膜堵塞和有机颗粒堵塞恢复效果较为明显,其中,可溶性有机物堵塞、不溶性有机物堵塞装置分别轮休至第9天、第20天后基本达到较好的恢复状态,当轮休时间足够充分,这2种堵塞类型基本可以恢复至正常状态.其中可溶性有机物堵塞恢复速度最快,其次是不溶性有机颗粒堵塞.并在规律研究基础上,进一步推导了2种堵塞类型的渗透系数恢复的动力学.研究同时发现,轮休操作对无机颗粒类堵塞基本没有恢复效果.
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