落干式人工湿地工艺对农村灰水处理的效能

Efficiency of Flooding-Drying Constructed Wetland Process for Rural Greywater Treatment

研究基于农村生活污水灰黑分离处理模式,针对农村灰水的水质水量特征,构建了一种以河沙、沸石为主要基质层填料的新型非饱和垂直流人工湿地——落干式人工湿地。文中探究了比脉冲体积、脉冲周期、比水力负荷率3种与水力条件相关的关键参数对农村灰水处理效果的影响。根据权重分析法计算得出在脉冲周期为4 h、比脉冲体积为106.88 L/m^(2)、比水力负荷率为3.56 L/(m^(2)·min)的条件下达到最佳综合处理效能,对COD_(Cr)、氨氮、TN、TP的去除率分别达到94.75%、92.74%、85.52%、71.34%。最佳运行参数下的长期监测发现,连续高负荷运行导致湿地堵塞,降低处理性能;运行5 d,休床2 d的休床策略能缓解堵塞现象,保证湿地运行的稳定性;减小湿地水力负荷有助于改善冬季低温对湿地运行的影响。总体而言,落干式人工湿地不需外加条件即可达到良好复氧效果保证污染物的去除率,系统简单易维护,在处理农村灰水方面具有良好的应用潜力。

Based on the characteristics of greywater in rural areas at home,a new type of unsaturated vertical flow constructed wetland was proposed,which was filled with river sands and zeolites.The effect of hydraulic parameters(i.e.,specific pulse volume,pulse period,and specific hydraulic load)on rural greywater treatment were investigated.According to the comprehensive analysis method,the best treatment efficiency could be achieved under the conditions of pulse period 4 h,specific pulse volume 106.88 L/m^(2),specific hydraulic load 3.56 L/(m^(2)·min),the removal rates of COD_(Cr),ammonia nitrogen,TN,and TP reached 94.75%,92.74%,85.52%,and 71.34%,respectively.Stable operation tracking showed that continuous high load operation may lead to wetland blockage,wastewater cannot seep down from the overflow mouth in time.The treatment performance was reduced need to rest.Stability of wetland operation could be ensured at 5 days operating and 2 days resting.Microbial activity was affected in the cold season with low temperature.The stability could be ensured in cold season by reduced hydraulic load basis of warm-season operation mode.In general,this newly constructed wetland can achieve well reoxygenation and efficient removal without additional conditions.Low construction and operating cost,simple management,and easy maintenance ensure its application in rural areas at home.