Study on the Decontamination Effect of Biochar-Constructed Wetland under Different Hydraulic Conditions

To explore the purification effect of biochar-constructed wetlands on rural domestic sewage, six types were constructed for experiments. Under different hydraulic conditions, removal effects each wetland chemical oxygen demand, ammonia nitrogen, total and phosphorus in sewage analyzed. The results showed that rates four pollutants first increased then decreased with increase retention time, optimal time range was 36–48 h. highest 97.34 ± 0.84%, 95.44 1.29%, 98.95 0.52%, 97.78 0.91%, respectively. demand (COD) rate first, load, load 10 cm/d. efficiency gradually weakened between 5 these 92.15 2.39%, 98.32 0.48%, 96.69 1.26%, 92.62 2.92%, Coconut shell shell-constructed proportion biochar matrix have best under wastewater is stronger, indicating addition helpful wetlands.