In the Australian cement industry, blended cement recycled from mixed materials is emerging as an alternative for greenhouse gas reduction.
Adding advanced material graphene oxide (GO) to waste clay can reduce carbon (CO2) emissions due to a decrease in cement content while maintaining similar strength to existing concrete.
The Korean Society for Waste Resource Circulation noted that it held the 3R international scientific conference on material cycles and waste management (3RINCs 2025) from the 11th to the 13th of this month on the first floor of Shinwa World in Seogwipo, Jeju.
Priyan Mendis, a professor at the University of Melbourne in Australia, introduced the Australian cement industry under the theme "The development of net-zero concrete in Australia toward carbon-neutral construction."
Professor Mendis said, "32% of global resources are used to construct buildings, and buildings account for up to 40% of total energy consumption," adding that "in Australia, there is a focus on building waste with various research efforts, particularly for innovative studies on concrete."
Australia produces about 29 million cubic meters of concrete annually. Notably, 1 cubic meter of concrete emits 430 kg of carbon dioxide into the atmosphere, with 58% of that coming from the cement component. This reflects Professor Mendis's explanation that efforts are being made to achieve carbon neutrality by using recycled materials as blended materials for cement.
Professor Mendis noted, "With the introduction of the Climate Change Act, the task has been assigned to reduce greenhouse gas emissions by 43% by 2030 compared to 2019," adding that "the atmosphere is one where many countries are failing to meet their targets, thus necessitating various research efforts for carbon neutrality alongside government incentive support."
Next, Camila Gunasekara, a professor at RMIT University in Australia, introduced measures to reduce cement content and enhance durability by utilizing waste clay. The Australian cement industry is focusing its efforts on developing low-carbon concrete by using waste clay suitable for blended materials.
Professor Gunasekara emphasized that in Australia, waste clay and GO are gaining attention as blended materials. By replacing up to 30% of cement content with plastic clay, high compressive strength was achieved in the blended cement.
Professor Gunasekara said, "Using blended cement allows for a reduction in cement content, making it possible to decrease greenhouse gases generated during the cement manufacturing process," adding that "the blended cement with GO has 22% less cement content and about 20% lower intrinsic carbon, yet it has strength performance similar to conventional concrete."
The international academic conference hosted by the Korean Society for Waste Resource Circulation is the first in 10 years since 2015. About 500 experts from more than 20 countries, including South Korea, China, Japan, and Australia, participated in this international academic conference. The Korea Cement Association, which has major domestic cement companies as its members, also attended the conference.