UC Irvine

With the development of membrane science, reverse osmosis is at its peak in terms of innovationsand developments. Its limitations, such as the high energy consumption, have been widely recognized. To eliminate said disadvantages, Forward osmosis (FO) is often viewed as a promising alternative in resource conservation, desalination, and wastewater treatment. This critical review is dedicated to exploring current applications regarding N2O elimination methods that utilize FO. As one of the primary causes of greenhouse effects, N2O emission in California is contributed mainly by agricultural soil (75%), where the combination of Fertilizer-drawn Forward Osmosis (FDFO) and Nanofiltration (NF) can be adopted to reduce N2O emission by treating fertigation water to reduce over-fertilization. An empirical model of soil emission of N2O shows a positive linear relation between the N fertilizer input and N2O emitted. Since fertigation is extensively used in agriculture fields, when a FO system is integrated into the fertigation process, employing FDFO and Nanofiltration (NF), the minimization of N2O emission through direct fertigation treatment can be achieved. Also, additional benefits are removing extra nitrogen and easing water shortage by treating brackish water. The energy consumptions of FO and FDFO are addressed in the end to test the applicability of different models.