Study on Method of Domestic Wastewater Treatment through New-Type Multi-Layer Artificial Wetland

The artificial wetland is comprised of such groundmasses as breakstone and gravel etc as well as aquatic plant attached to it. The wastewater flows in or beneath surface layer of groundmass at the wetland, and decomposes nutritive materials in water through such a serial processes as attachment to groundmass, absorption by plant and microbial conversion etc, which belongs to distinctive soil-plant-microbe system that is differentiated from the wetland. This paper introduces a new-type multi-layer artificial wetland for treatment of domestic sewage, and analyzes the removing effects of CODCr, BOD5, NH3-N, TN and TP in this approach. The results indicate that when hydraulic loading reaches approximately 0.44 m³/(m² d) and hydraulic retaining duration reaches 3 days, the effect of removing CODCr, BOD5, NH3-N, TN and TP from the wetland is relatively good. Thus the effluent exceeds farmland irrigation water quality standards.