长期污水处理下无植物BRC渗透性能及脱氮性能间变化规律

通过对系统渗透系数及氮素浓度变化的长期监测,考察长期污水处理条件下无植物生物滞留池(Biological Re-tention Cell,BRC)渗透性能及脱氮性能之间的变化规律.结果表明,无植物BRC在长期污水处理运行过程中,TN去除率随着渗透系数的降低而降低.脱氮效率降低是由于系统内基质堵塞导致,渗透系数降低是由于系统内无机/有机化合物在基质内部颗粒间隙的积累、基质间隙生物量的积累,以及气体气隔作用导致的装置堵塞.对于COD和TP等其他污染物指标,生物滞留系统有较明显的去除效果且具稳定性,氮素较低的去除率为BRC系统的主要约束性指标.

Changes between Permeability and Denitrification Performance of Unplanted BRC under Long-term Sewage Treatment

Through long term monitoring of system permeability coefficient and the change of nitrogen concentration, the variations between permeability and denitrification performance of an unplanted biological retention cell (BRC) under long term sewage treatment were investigated. The results showed that TN removal rate decreased with the decrease of permeability coefficient in long term sewage treatment of unplanted BRC. The decrease of denitrification efficiency was caused by matrix blockage in the system. The decrease of permeability coefficient was caused by the accumulation of inorganic/organic compounds in the particle gap inside the matrix, biomass accumulation in matrix gap, and device blockage caused by gas barrier. BRC system had obvious effect and stability on removing COD, TP and other pollutants. The low nitrogen removal rate was the main constraint index of BRC system.