垂直潜流人工湿地堵塞机制：堵塞成因及堵塞物积累规律

为解决垂直潜流人工湿地的堵塞问题,需首先探明人工湿地的堵塞成因和堵塞物在人工湿地中的分布规律.在发生堵塞的垂直潜流人工湿地中,通过研究基质间各物质与雍水面积、基质间空隙率之间的相关关系,发现人工湿地发生堵塞的成因主要是基质层中不可滤物质的积累,并得出以砂子为基质的人工湿地每mL基质间不可滤堵塞物超过18.23 mg时即会出现雍水表观现象;同时研究发现,在本试验条件下,人工湿地布水口周围容易先产生堵塞现象,堵塞层主要分布于距布水管下10～20cm处;基质中不可滤无机物积累的程度比不可滤有机物更明显,且有随着水流方向沿程迁移的趋势;有机物质积累于基质深度基本呈负相关性,基质越深,有机质含量越少,雍水后基质表层有机质含量高于其它各层.

Clogging mechanism in vertical-flow constructed wetland: clogging cause and accumulation distribution characteristics

In order to solve the problem of clogging in the vertical-flow constructed wetland, the reason of clogging and the distribution rule of clogging substance in the vertical-flow constructed wetland was investigated first. Based on the correlativity of accumulation quantity and banked-up water area or lacuna rate in constructed wetland systems, the results show that the accumulation of non-filter materials is the main reason of clogging. The banked-up phenomenon will occur when the accumulation of non-filter materials is more than 18.23 mg in the per milliliter substrate. Under the condition of this experiment, the clogging phenomenon is easy to take place around current outlet, and accumulation materials mainly distribute in the 10-20 cm upper layer under water pipe. In the substrate, the accumulation degree of that of non-filter inorganic is more obvious than non-filter organic, with the trend of migrating along the water direction. The accumulation of organic and the depth of substrate is negatively correlated, i.e. deeper substrate,less organic content. The organic content in the surface layer of substrate is higher than that in other layers after banking up.