Recovery of Nitrogen and Phosphorus as Nutrients From Wastewater Using Sorbents and Its Potential Reutilization as a Soil Conditioner: A Review

Wastewater treatment is crucial to ensure environmental sustainability and the availability of clean water for human consumption. It is of utmost importance that the valuable nutrients in the wastewater are recovered. Recently, many researchers have made interesting discoveries using green waste or minerals to treat wastewater and recover nutrients from wastewater. Nutrients which encourage eutrophication of water resources, such as nitrate, nitrite, ammonium, and phosphorus, are the common ones being explored. The nutrients are adsorbed on sorbents, which are recycled from waste and biodegradable material. Upon adsorption of nutrients, the spent sorbents are categorized as green and eco-friendly material which can be further utilized as a soil conditioner. Thus, this review discussed different types of sorbents and its respective efficacy towards nutrient adsorption and feasibility to be recycled as soil conditioner. Factors affecting the performance of the sorbents were detailed and comparisons were made for the best application as soil conditioner. Suggestion was outlined for future focus areas in this work and potential future application in real case scenarios. This review would be beneficial to researchers to achieve a cradle-to-cradle concept for wastewater nutrient recovery.