The National Environment Agency (NEA) announced earlier today (25 September) that it had issued a Request for Proposal (RFP) to study the technical feasibility of recovering mixed landfilled materials.
According to the press statement, the purpose of the study is to “better understand” how Singapore could extend the lifespan of Semakau Landfill, as well as avoid future costs of constructing another offshore landfill.
The mixed landfilled materials comprise incineration bottom ash (IBA) and incineration fly ash (IFA) from waste-to-energy (WtE) plants and non-incinerable waste (NIW) from industries, which were landfilled at the Phase I cells of Semakau Landfill.
This study was prompted due to the prediction that Semakau Landfill will run out of space by 2035. The NEA explained that the incineration ash generated from the WtE plants will “have nowhere to go”.
Therefore, the Agency intends to explore “innovative and novel solutions” to prolong the lifespan of Semakau Landfill with this RFP.
“Through this RFP, we look forward to exploring innovative and novel solutions for prolonging the lifespan of Semakau Landfill and spur Singapore’s drive towards becoming a zero waste nation.”
It was revealed that the point of this study is to assess the technical and economic feasibility of refreshing the landfill space through extracting the landfilled materials and finding suitable applications for the recovered materials, which the NEA believed could potentially be used as sand or aggregate replacement in various applications.
The NEA proceeded to report that approximately 15 million tonnes of mixed landfilled materials have been disposed of in 10 of the landfill cells, and the Phase I of Semakau Landfill has 11 landfill cells.
To extend the said Landfill’s lifespan beyond 2035, the Agency believed that it is “crucial” to reduce waste generation.
“A key waste reduction target in the Zero Waste Masterplan is to reduce the ash and waste sent to Semakau Landfill each day by 30 per cent by 2030.”
The Chief Executive Officer of NEA, Tan Meng Dui, mentioned that research and development are in progress to “truly close the waste loop” for the range of end-of-life waste and residues that would end up at Semakau Landfill.
“We have seen the possibilities of using slag produced from MSW, through a high-temperature gasification process, as a form of NEWSand that has been used to make concrete benches, a footpath in Tampines town and the new concrete plaza in front of the Environment Building.”
“NEA is spearheading R&D efforts to go even further, so as to truly close the waste loop for the range of end-of-life waste and residues ending up at Semakau Landfill. This R&D initiative seeks to develop safe and sustainable solutions to turn the trash dumped into a landfill, into treasure that will have new future uses.”