Recent technological developments and challenges for phosphorus removal and recovery toward a circular economy
Minh T. Vu, Hung Cong Duong, Qilin Wang, Ashley J. Ansari, Zhengqing Cai, Ngoc Bich Hoang, Long D. Nghiem
Abstract
This review aims to summarise the current state of the art technologies for phosphorus recovery from waste and wastewater. Information corroborated here shows a clear relationship between PO4-P content in the liquid phase and the cost of phosphorus recovery. In fact, all current commercial scale operations in this review involve a phosphorus-rich waste stream. In most cases, phosphorus recovery is achieved via two key steps: solubilising phosphorus into water and then phosphate recovery via chemical precipitation/crystallisation. Recent development has also included enrichment and pre-treatment of the phosphorus rich liquid stream. Phosphorus is also a contaminant in the aquatic environment. Thus, this work also reviews the post-treatment of the liquid stream after phosphorus recovery for environmental discharge or water reuse. This review places a spotlight on the requirement for further research work especially on phosphorus enrichment at pilot- and full-scale level. The review also demonstrates the need for further research on pre-treatment and post-treatment to complement the recovery process via chemical precipitation.