Recovery and Treatment of Phosphate from old Landfills

The annual German agricultural demand for phosphor in fertilizing purposes accumulates to about 125.000 Mg P. It is expected that, in the medium-term, the recovery of phosphor from wastewater treatment measures will be able to deliver two thirds of this demand, after the phaseout from soil-related sewage sludge utilization. In this context, the Leichtweiss-Institute examined the possible contribution of landfill-mining measures on minimizing the remaining gap.

Therefore, the potential phosphor content of different landfill types was evaluated. Furthermore, samples from where taken from 6 different landfills, in order to determine the content of phosphor and pollutants as well as the applicability of the materials to existing phosphate recovery techniques. The derived data formed the basis for several landfill-mining approaches. Ecologic and economic balancing of these approaches facilitated to identify opportunities and limits of landfill mining as a source of phosphor and to deviate recommendations.

The final report is published online on the website of the Ministry for Climate Protection, Environment, Agriculture, Conservation and Consumer Protection of the State of North Rhine-Westphalia as the funding institution. The report can be found via the following link (German):