06. An ecological engineering and energy saving model for wastewater treatment at decentralization sources

Abstract

The ecological engineering model of mixing soil layers is an underground filter tank technique that uses natural materials derived from soil (i.e., clay minerals, laterite cinders, etc.) as pollutant adsorbents. The surface of the tank is covered with soil and planted with natural grasses. The technique had high treatment efficiency, with N and P treatment efficiency of 60 - 70 %, due to anaerobic and aerobic mechanisms in the soil layers. The concentration of BOD­₅ and COD were significantly reduced, ensuring the quality according to QCVN 14-MT:2015/BTNMT column B1. The technique uses completely natural materials, environmentally friendly and low operating costs. This technique is very suitable for households, agencies, schools, restaurants and hotels,... to treat wastewater in order to protect the environment. The technique applied to decentralised sources will reduce the operation capacity of centralised wastewater treatment plants.