Waste

With increasing human activities and population growth, billions of tonnes of solid waste are generated worldwide every year. Effective waste management across all production sectors is crucial to decrease the amount of waste for disposal, save space in landfills and conserve natural resources.

NTU scientists are finding ways to recycle and transform food waste, electronic waste (e-waste) and municipal waste into new products and energy.

Producing energy from municipal waste

NTU and NEA have launched a new Waste-to-Energy Research Facility that turns municipal solid waste from the NTU campus into electricity and resources. Located in Tuas South, the facility is a $40 million project supported by the National Research Foundation Singapore, NEA, the Economic Development Board (EDB) and NTU.

Equipped with a unique slagging gasification plant, that is able to heat up to 1,600 degrees Celsius compared to conventional mass burn incinerators which operate at around 850 degrees Celsius, the high temperature of the plant turns rubbish into syngas (mostly carbon monoxide and hydrogen) that can be used to produce electricity, slag – a glass-like material that can potentially be used as construction material known as NEWSand – and metal alloy granulates that can be recycled.

Extracting metals and recycling plastics from e-waste

Scientists from the Singapore-CEA Alliance for Research in Circular Economy (SCARCE) and NEWRI are using eco-friendly methods of recycling e-waste. One project involves using compounds from discarded orange peels to extract high value metals from batteries. There are now multiple projects underway on eco-friendly processes to tackle other e-waste, for instance, transforming toxic plastics found in items like circuit boards into reusable resources with the help of harmless chemicals.

Additionally, NTU has partnered the Alliance to End Plastic Waste (AEPW) and jointly committed S$1.2 million to fund innovative solutions for the global plastic waste problem. NTU researchers are also working with Imperial College London and the University of Nottingham on a carbon-neutral bio-upcycling solution for plastic waste management by converting polyethylene terephthalate (PET) into compounds of industrial value.

Reducing waste during manufacturing

At the HP-NTU Digital Manufacturing Corporate Lab, researchers are focusing on digital manufacturing technologies, specifically in areas of advancing 3D printing, artificial intelligence, machine learning, new materials and applications, cybersecurity and customisation.

Compared to conventional manufacturing techniques such as machining, milling and moulding, less waste is generated by digital manufacturing technologies such as 3D printing as designs are directly transformed into products.

Examples of 3D printed products from the HP printer, which allows for flexible designs with soft plastic