Resource Recovery from Wastewater By Forward Osmosis Based Process

Currently, aerobic biological processes are dominant in wastewater treatment which consumes large amount of energy, about 0.5-1.5 kWh/m3. These pose a long-term threat to water industry. On the other hand, the major component of pollutants in wastewater are organics, which are actually an energy source. The calorific value of wastewater is 0.0041 kWh/g COD. This means that the energy present in wastewater is more than the energy consumed in the treatment process. In our study, a now FO based process is developed to preconcentrate pollutants in wastewater by FO into a small volume of concentrate, which makes it economically fesible to convert organics to biogas and recover nitirents. The permeate of FO unit can be further treated to produce high quality free water and regenrate draw solution. The study provides new insights on development of low-cost technologies for water recycling, renewable energy generation and resource recovery from wastewater.