jaue2016096: Operating Efficiency Comparison and Analysis of the Sludge Drying Reed Bed

Abstract

Sludge Drying Reed Bed (SDRB) is a new sludge treatment system by combined constructed wetland and sludge drying bed. The sewage sludge is loaded on the surface of SDRB periodically, the water released from the sludge during dewatering is treated as it percolates through the media layer and discharged through drainage pipe on the bottom, the solid is retained on the surface of media and dewatered by evapotranspiration. On the base of investigating sludge stabilization effect by SDRB on the sewage sludges with different organic matter contents, the paper summarizes the performance experience concerning degree of mineralization, removal of nutrients such as nitrogen and phosphorus, degradation of micro-pollutants and in SDRB. After two years loading and one year resting periods, organic matters in the sludge is stabilized effectively, the stabilization degrees of higher and lower organic matter content sludges are 54.50% and 58.20% and meets the requirements of sludge stabilization standard (GB 18918-2002) and urban garbage for agricultural application standard (>10%) (GB 8712-87) in China; the degrees of nitrogen and phosphorus contents in the stabilized sludge are higher enough to use as plant nutrients, nitrogen in higher and lower organic matter content sludges decrease from 7.10% to 3.10% and from 2.52% to 0.98%; micro-pollutants such as polycyclic aromatic hydrocarbons (PAHs) are removed effectively, the removals of PAHs in higher and lower organic matter content sludges are 67.28% and 32.64%, the reed plays a key role during the PAHs degradation and transportation.