Wastewater‐recovered struvite evaluation as a fertilizer‐phosphorus source for corn in eastern Arkansas

Abstract

AbstractThe perception of wastewater as a resource rather than a pollutant has not been well emphasized. Phosphorus (P) can be precipitated from wastewaters as the mineral struvite (MgNH4PO4·6H2O), which can be a potential sustainable alternative to the limited, rock phosphate (RP)‐dependent, traditional fertilizer‐P sources for agricultural production. This field study evaluated the effects of electrochemically precipitated struvite (ECST) and chemically precipitated struvite (CPST) compared with other conventional fertilizer‐P materials (monoammonium phosphate [MAP], diammonium phosphate [DAP], triple superphosphate [TSP], and RP) on corn (Zea mays L.) response in two consecutive growing seasons in a P‐deficient, silt‐loam soil (Aquic Fraglossudalf) in eastern Arkansas. Averaged across years, corn yield was numerically largest from ECST (12.9 Mg ha–1), which differed (P < .05) from all other treatments and was numerically smallest from DAP (10.1 Mg ha–1), which was similar to MAP (10.7 Mg ha–1), CPST (10.3 Mg ha–1), and RP (10.3 Mg ha–1). Corn yield and kernel P uptake from ECST were at least 1.2 times greater (P < .05) than from CPST, TSP, DAP, and RP. Yield from ECST was 1.2 times greater (P < .05) than from MAP. A partial budget analysis showed that, across both years, fertilizer‐P treatment net revenues for ECST were greater than those associated with the other fertilizer‐P sources. Results demonstrated that wastewater‐recovered struvite materials have the potential to be a sustainable source of P for corn production in P‐deficient, silt‐loam soil from both a technical and economic perspective.