Purification effect of bioretention with improved filler on runoff pollution under low temperature conditions

In recent years, there have been a number of studies on bioretention during hot summer, with only few reported low-temperature winters. The application in cold areas still lacks effective guidance. this study, runoff simulation experiments were conducted to explore the influence wood chips filler and water treatment residue removal pollutants under different packing gradations low temperature conditions. Under temperature, nitrate nitrogen rate decreased from 70% 90% autumn −23%- 35% winter, total 75 20%–50% ammonia phosphorus exceeded entire experiment. Water maintained high experiment, above 80%. effluent concentration was higher than 7.3 mg/L 8.5 mg/L, respectively, most time. However, at COD two fillers 25%–50%, which very poor. Therefore, observed be better suited for runoff, while had effect winter. Thus, northern China, appropriate should selected considering quality characteristics area.