POSCO is leading efforts to consolidate the group's capabilities for the resource utilization of by-products and the implementation of a circular economy.
On the 11th, POSCO signed a business agreement to expand the use of slag cement with GS Engineering and Construction, five construction companies, Hanil Cement, EUGENE Corporation, and seven other ready-mixed concrete companies, along with the Korea Concrete Institute and Pohang Institute of Industrial Science and Technology (RIST).
This agreement was established to develop ready-mixed concrete production technology using type 1 slag cement and to prepare quality management guidelines to contribute to the improvement of ready-mixed concrete quality in the construction industry. Slag is a representative by-product generated during the steel manufacturing process, consisting of the material that remains after separating iron from iron ore. The slag generated in blast furnaces is used as a raw material for cement instead of natural resources such as limestone. As cement reacts with water, the resulting heat of hydration can be lowered, which can reduce concrete cracking and increase durability and strength.
POSCO and RIST will ensure a stable supply of slag while developing utilization technologies for slag cement. The cement and ready-mixed concrete companies will manufacture high-quality ready-mixed concrete using slag cement, while construction companies will apply this to construct more robust structures. Additionally, the Korea Concrete Institute will inspect the quality of ready-mixed concrete made from slag cement and ultimately establish quality management guidelines, contributing to the dissemination of this in the construction industry.
Previously, ready-mixed concrete companies mixed powdered slag directly with cement and other materials. If the powdered slag was excessively added arbitrarily or if unverified third-party materials were mixed in to manufacture ready-mixed concrete, there was a possibility that the quality in terms of strength and durability could decline. This could lead construction companies to have a negative perception of slag cement, acting as a limitation to the expansion of slag utilization.
However, with this agreement, cement companies can manufacture slag cement with a uniform mixing ratio of cement and slag, after which ready-mixed concrete companies will use this to manufacture ready-mixed concrete, and construction companies will be able to use those ready-mixed concrete products with assured quality. This is expected to enhance the overall quality of construction materials that use slag.
A POSCO official noted, "Despite the unprecedented crisis in the steel industry, POSCO plans to secure the inherent competitiveness of steel based on super-gap technology and to enhance the added value of by-products that inevitably arise during the steel production process by consolidating the group's technological capabilities."