Zero waste for zero emissions in a world of modern consumerism
The current consumer economy has been enormously wasteful. We acquire resources, make products, use them, and then throw them away. “The Centre aims to be a global research centre in the area of solid waste recycling. We support the Hong Kong government’s policy of achieving carbon neutrality by 2050. We are also committed to minimising the waste that goes to landfills,” said Ir Prof. POON Chi Sun, Director of RCRE.
In fact, carbon neutrality is only one of the many environmental issues that RCRE has pledged to tackle. A sustainable society necessitates a shift in consumer behaviour. The Centre hopes to develop Hong Kong and the Greater Bay Area into models of resource engineering towards a circular economy. A circular economy moves away from wasteful consumerism. It stresses the use of “waste” as a resource to manufacture new products and deliver services; as a result, the whole economy becomes less resource intensive.
Novel ways of managing resources and waste
The realisation of a zero-carbon society and a green economy is one of the biggest problems on our planet, requiring combined efforts and wisdom from policymakers, scientists and community. The Centre’s four main research directions provide multifaceted solutions to this complex problem. “Waste recycling and management has great relevance to policy-making and social implications. Our studies under Policy and Society focus on social impact assessment and policy evaluation, social entrepreneurship for waste recycling, and individual waste management behaviours. Environmental and Economic Impact includes life cycle analysis of organic and inorganic waste, so that it helps inform decisions about proper recycling technologies for the reutilisation and sustainable applications of various waste materials,” Prof. Poon explained.
“Under Waste Valorisation Technology, we explore the reuse of waste materials like algae, food, yard waste, etc., and convert them into useful products like biochar and biofuel. Under Recycling and Sustainable Construction, we recycle the waste from construction and other materials and turn them into useful construction materials,” Prof. Poon said. The Centre developed an Eco-Block technology which utilises these construction and demolition wastes together with recycled glass and incinerator ashes to make construction materials. The Centre also developed a carbonation technique that sequesters carbon dioxide and transfers concrete waste powder into high-value nano-construction materials.
Cutting-edge research platforms and facilities for innovative and advanced waste technologies
The scientific study of waste and wide-ranging resources on our planet is highly complex and technical, requiring high-tech infrastructure. The six research facilities on the PolyU campus are where RCRE research outputs are incubated. These include the Bioenergy Research Laboratory dedicated to biofuel and non-catalytic research, the Concrete Materials Laboratory for the characterisation of cement-based and constructional materials, the Road Research Laboratory that supports the performance testing of road and pavement materials, the Transport and Highway Engineering Laboratory for conducting experiments on bituminous materials and transport-related measurement, the Water and Waste Laboratory for extensive characterisation of physical, chemical and biological samples, as well as the Joint Laboratory on Solid Waste Science in which research on safe waste treatment and resource utilisation technologies is conducted.
Waste management is an acute problem in Hong Kong. The three major landfills in the region are expected to be filled by 2030, and their capacity is decreasing fast. “In the 2021/22 year, our Centre obtained a total grant of over HK$16 million from external bodies, to conduct fundamental and impactful research on woody waste, waste glass and incineration ashes,” Prof. Poon said.
Among the four externally funded projects are two large projects funded by the HKSAR Government’s Green Tech Fund. In Biochar-enhanced Construction Materials for Sustainable Waste Management and Decarbonisation, Prof. Daniel TSANG, Professor in the Department of Civil and Environmental Engineering, leads his team in developing innovative designs and science-informed manufacturing technologies for biochar-enhanced construction materials. This work has given rise to pioneering products, including a biochar partition block and biochar porous paver.
“I am leading a team on the project Low-carbon Transformation of Construction Materials Using Waste Glass, which just started in January 2023. We will use glass powder and cullet derived from waste glass bottles to produce high-performance construction materials,” Prof. Poon explained. “Glass waste is a major component of solid waste in Hong Kong, and its recovery rate has consistently been under 20%. On the other hand, in the construction industry, concrete production accounts for about 8% of global anthropogenic carbon dioxide emissions.” The project is expected to reduce the production of glass-based and embodied-carbon concrete materials, thus reducing carbon emission that results from glass waste and concrete production.
Ambitious efforts by high-calibre researchers and engaging the wider community for a greener tomorrow