An overview of technologies to recover phosphorus as struvite from wastewater: advantages and shortcomings.

Phosphorus (P) is a significant limiting nutrient which is essential for all forms of lives. However, phosphate rock reserves are depleting rapidly due to population growth. At the same time, several countries have imposed legislative regulations on P-release into surface waters due to eutrophication.

Impact of supersaturation ratio on phosphorus recovery from synthetic anaerobic digester supernatant through a struvite crystallization fluidized bed reactor.

Over the past few decades, several technologies have been developed to recover phosphorus (P) as struvite from wastewater. Although these technologies have achieved reasonable P-removal efficiencies, these technologies are associated with several shortcomings such as high capital and operating costs, longer crystallization time and production of low-quality product. This study focussed on the development of an efficient technology by designing a new fluidized bed reactor (FBR) and determining its optimum operating conditions.

Recovery of phosphorus from dairy manure: a pilot-scale study.

Phosphorus was recovered from dairy manure via a microwave-enhanced advanced oxidation process (MW/H2O2-AOP) followed by struvite crystallization in a pilot-scale continuous flow operation. Soluble phosphorus in dairy manure increased by over 50% after the MW/H2O2-AOP, and the settleability of suspended solids was greatly improved. More than 50% of clear supernatant was obtained after microwave treatment, and the maximum volume of supernatant was obtained at a hydrogen peroxide dosage of 0.