Experimental research on treatment for ammonium-nitrogen from diosgenin wastewater by MAP process

The method of magnesium ammonium phosphate (MAP) precipitation was used to remove high concentration of ammonia-nitrogen wastewater. A lab scale study about diosgenin wastewater was conducted to optimize the reaction condition by single factor experimentation. MgCl
2
·6H
2
O and Na
2
HPO
4
·12H
2
O were used as precipitants. The experimental results demonstrated that the removal rate of ammonia nitrogen was up to 63.44% when pH value was 9.5, the molar ratio of Mg
²⁺
:NH
4
⁺
:PO
4
³⁻
was controlled at 1∶1∶1 and the reaction time was 2 hours.