Magnesium ammonium phosphate precipitation using seawater

In this study, application of seawater as a magnesium source to magnesium ammonium phosphate (MAP) precipitation was experimentally investigated using synthetic samples containing initial concentration of 100 mgN L-1 NH(4)Cland leather tanning wastewater. The dilution ratio was defined and found to be a main parameter determining the costs of the process as well as the extent of interference caused by seawater composition. While the increase in ionic strength and alkalinity had a slight effect on the MAP precipitation, introduction of calcium ions through the use of seawater proved to have an adverse effect on the process. The use of seawater as a magnesium source yielded a similar ammonia removal performance as the application of MgCl2 to both synthetic samples and leather tanning wastewater.