Application of Recycled Fish Wastes for the Recovery of Struvite Fertilizer From Actual Landfill Leachate

摘要

The crystallization of struvite (MgNH4PO4.6H2O) is known as an effective way for recovering nutrients from landfill leachate (LL). Recently, several studies have been done to examine nonconventional sources of phosphorus, in order to improve the applicability of struvite technology. This study aimed at investigating the applicability of recycled fish wastes as a new source of P to recover MAP from real LL. A solution rich with P (P-solution) was extracted from fish wastes ashes, and mixed with pure magnesium oxide (MgO) before applying the resulted mixture to leachate samples. The experimental results showed reductions of different parameters; total suspended solids (TSS), chemical oxygen demand (COD), turbidity and color were removed with approximate rates of around 32%, 31%, 37% and 51%, respectively. Besides, about 70% of ammonium-nitrogen (NH4-N) was converted to struvite precipitate. X-ray diffractometry (XRD) test confirmed the presence of struvite crystals in the obtained precipitates. Moreover, the utilization of Mg-P mix was significantly competent in comparison with conventional reagents.