Exploiting landfill sites
Enhanced Landfill Mining (ELFM) is a concept that performs the valorisation of materials and energy from a landfill site as sustainably as possible with both a maximisation of material recycling and an optimal energy production. Through a thorough separation of the waste the best possible choice can be made. Already since 2012 OVAM has been testing various techniques and combinations of techniques on a pilot scale.
Landfill sites in Hasselt, Evergem and Zuienkerke have already been investigated. Within the concept of Enhanced Landfill Mining, OVAM commissioned an innovative separation of landfilled waste whereby it is indicated what flows have been released and what opportunities for valorisation exist. Five contractors responded and formulated a technical and financial proposal.
In parallel, OVAM launched a study assignment for the technical and economic monitoring and evaluation of the used separation tests.
Different questions were addressed here:
- What fractions are obtained after separation and in what quantities?
- How pure are the various fractions?
- What are the opportunities for valorisation?
- What is the degree of mobility of the used separation technologies?
- What is the profitability?
Each contractor received around 100 tons of mixed urban waste from an official soil remediation of a landfill site in Zuienkerke. The waste was mostly dumped there in the 60s and is mainly household waste. These waste flows were separated by the contractors in partial flows with a view to a maximal materials and/or energy recovery. A combination of various separation techniques was tested: sieving, band magnets, hydrocyclones, belt filter press, windshifting, form separators, eddy currents, optical separation, aqua engine and ballistic separation. This test has shown that a separation is possible that allows the recovery of a larger portion of dump material as Waste to Materials and a limited proportion as Waste to Energy. Also on site a test was conducted to remove the plastic from the landfilled materials through a combination of various sieve techniques and wind shifter.
On the basis of the results of the separation tests and the findings of the contractors a number of proposals were formulated for conducting further innovative research on waste separation.
