Singapore dedicates facility to recover metal from incinerator ash

Singapore’s National Environment Agency (NEA) has awarded a contract to REMEX Mineralstoff GmbH (REMEX) of Germany to develop and operate a metal recovery facility that will recover ferrous and nonferrous metals from incineration bottom ash (IBA) generated by incineration plants in the country.

The NEA says the metal recovery facility is part of its long-term strategy to manage solid waste in Singapore and part of the government’s plans to move towards a resource efficient society. Currently, ferrous metals between 10 millimeters (mm) to 300 mm in size are being recovered from the incinerator bottom ash using magnetic separators at the incineration plants, with the residual ash sent to the Semakau Landfill for final disposal. In awarding the contract to REMEX, the NEA says that this conventional treatment system leaves the non-ferrous metals such as aluminum and copper, and the remaining smaller pieces of ferrous metals that are still of economic value, intact in the residual ash.

“The setting up of REMEX’s metal recovery facility is part of NEA’s long-term plan to improve resource efficiency. NEA is currently studying the possibilities for ash reuse, which will help resource-scarce Singapore to further increase resource recovery, as well as extend the lifespan of Semakau Landfill,” says Ronnie Tay, NEA’s CEO.

REMEX is expected to begin construction on the facility in October 2014 and have the facility operational by the middle of 2015. The project is expected to cost around $12 million. When fully operational the facility will be able to process 1,800 metric tons of incinerator bottom ash per year that are produced by the four incineration plants in the country. At the facility metals will be recovered through the use of conveyors, magnetic separators and eddy current separators. REMEX expects to recover around 90 percent of the ferrous metal greater than 4 mm and a slightly lower proportion of nonferrous metals above the 2 mm threshold.

The resulting IBA could be further treated so it could be used as materials for road construction and concrete applications. The remaining incinerator bottom ash will be landfilled.

Following the extraction of the metal, REMEX will ship the material to Europe where the metal will be further separated and sold. However, the NEA says that the company is looking for local end markets for the material.

REMEX operates similar facilities in the Netherlands and Germany. To operate the Singapore facility the company has set up a local, wholly owned subsidiary known as REMEX Minerals Singapore Pte Ltd.