Ammonium Removal From Landfill Leachate By Struvite (magnesium ammonium phosphate) Precipitation.

The treatment of leachate is a focal point of landfill management. Every landfill produces leachate,

and consequently, every landfill must treat its leachate in one way or another. A popular option is to send

leachate to a wastewater treatment facility, either through a direct sanitary sewer main or by tanker

truck. Either option represents added management costs. On top of this, ammonium concentrations

present in the leachate can further complicate the treatment process. It is typical that leachates with

high ammonium concentrations encounter a surcharge from wastewater treatment facilities. In

addition, leachate recirculation is also practiced by some landfills. While recirculation can lead to higher

biogas production, ammonium levels can spike, thereby rendering methanogenic bacteria ineffective. For

these reasons, a pretreatment method to remove ammonium needs to be explored. Precipitating

ammonium in the form of magnesium ammonium phosphate, or struvite, is an attractive management

alternative. Besides removing ammonium from the leachate, this pretreatment technique converts

ammonium into a reusable product. Struvite has been shown to be an excellent fertilizer, with heavy

metal concentrations below conventional store-bought fertilizers. This proposed study will seek to

optimize the operating conditions for producing struvite from landfill leachate and test the effectiveness

struvite as a multi-nutrient fertilizer.