Many countries around the world have joined to declare the sustainable net-zero policy since European Union (EU) released the ‘European Green Deal’ in 2019. Korean government also declared the ‘Korean Green New Deal for Net-zero by 2050’ in 2020, which includes i) green transition of infrastructures towards net-zero society, ii) low-carbon decentralization, and iii) innovation in the green industry and sustainable society. Crude steel production in Korea is about 70 million tonnes per annum (2021) and CO2 emissions per capita in 2020 increased more than 200% with reference to that in 1980. It is well known that global CO2 emission from iron and steel sector is ca. 7%, which is approx. 1/3 of industrial energy use. In Korea, we have a long-lasting national project, called “COOLSTAR (CO2 low emission technology of steelmaking and hydrogen reduction).” So, in the present lecture, the recent work regarding the fundamental research for the use of hot briquetted iron (HBI) from direct reduced iron (DRI) in an electric arc furnace (EAF) process will be discussed.

Alternatively, the recycling of e-wastes and recovery of precious and rare metals from various industrial wastes such as catalysts, sludges, slags, etc. is highly important to achieve the less emission of CO2 in non-ferrous industrial sector. The fundamental knowledge of thermochemistry, reaction kinetics and physicochemical properties of slags such as viscosity is necessary to design and improve the metallurgical processes to materialize the circular economy.