不同类型潜流湿地处理养猪废水的对比

针对养猪废水的水质特点,在同等条件下开展了2种类型潜流湿地处理效果的对比研究。实验结果表明,水平潜流湿地(HSSF)与垂直潜流湿地(VSSF)由于结构设计的不同造成其布水方式和系统内部水力流态的不同,从而导致了两系统对养猪废水处理效果的差异;当水力负荷为0.02 m3/(m2.d)时,两系统对养猪废水中COD的平均去除率分别为93.18%和93.10%,对TN的平均去除率分别为53.44%和81.43%,对NH4+-N的平均去除率分别为52.64%和84.62%,对TP的去除率分别为88.41%和95.71%;垂直潜流湿地可充分利用填料层,可增强系统的复氧能力,还可实现填料层中好氧区、缺氧区和厌氧区的共存,使硝化作用与反硝化作用在同一系统内完成,提高了系统的脱氮能力,而且改善了养猪废水中其他污染物的去除效果。因此,结合处理效果和出水水质的稳定性,对于浓度较高的畜禽养殖废水,选择垂直潜流湿地较为合适。

Comparison of two different constructed wetland systems to treat swine wastewater

Comparative study of two different types of constructed wetlands for swine wastewater treatment was carried out. The results showed that, there was a significant gap in the treatment effects between horizontal subsurface flow constructed wetland (HSSF) and vertical subsurface flow constructed wetland (VSSF) due to their inherent difference in inflow modes and hydraulic flow state. As the hydraulic loading rate was 0.02 m³/(m²·d), average removal efficiencies of HSSF and VSSF were as follows: 93.18% and 93.10% for COD, 53.44% and 81.43% for TN, 52.64% and 84.62% for ammonium nitrogen, 88.41% and 95.71% for TP, respectively. It was considered that all the medium in the VSSF could be fully utilized, and its ability of oxygen supplement could be strengthened. In addition, aerobic zone, anoxic zone and anaerobic zone could coexist so that nitrogen removal rate was improved by nitrification and denitrification in VSSF. Furthermore, removal rates of other pollutants were also improved simultaneously. It was implied that VSSF was more effective for treating livestock wastewater.