Implement Zero Waste, This Steel Industry Also Produces Green Aggregate
In an effort to implement the concept of a circular economy, zero waste and a green environment, the largest private steel company in Indonesia, PT Gunung Raja Paksi, Tbk (GRP) has succeeded in processing factory waste into other useful products. One of them is green aggregate, which has high economic value. This was conveyed by the President Director of GRP Abednedju Giovano Warani Sangkaeng to the media today.
“GRP really cares about the environment. For this reason, we utilize the remaining steel slag production to be used as green aggregate. This green aggregate innovation is part of a zero waste philosophy that encourages people to be wise in maximizing resources, so that products can be reused. This will form a circular economy, an environmentally friendly system that maintains the value of materials so that they can be used over and over again,” he explained.
This effort, he continued, is also a form of implementing the company's Environment, Social, and Governance (ESG) program.
In producing green aggregate, continued Argo, the steel slag is first separated and then crushed into smaller sizes. This material contains several oxides such as CaO, MgO, Fe₂O₃, MnO₂ and SiO₂, which are beneficial for other industries and the environment.
“We produce five types of green aggregate based on size. Sand Type measuring 0-4 mm, Screening Type 4-8 mm and 8-12 mm, and Split Type measuring 12-20 and 20-50 mm," he explained.
The division of the various size categories, he explained, to suit the user's industry. For example, a suitable product for the brick and paving block industry is the Sand Type. Meanwhile, the ready mix concrete industry and road base PU contractors can use Sand, Screening, and Split Types.
According to Argo, applications for the use of green aggregate have been developed in many developed countries. Apart from the construction sector, other fields such as agriculture can also be used. “Silica in green aggregate is very good as a fertilizer medium to increase plant vigor and resistance to disease. In addition, it is also porous and alkaline so it is effective in neutralizing soil acidity,” he said.
As for road construction, because green aggregate or green concrete is hard, wear-resistant, adhesive, and rough. Thus, continued Argo, there is no need to doubt the quality. "The use of green aggregate can be one of the right solutions so that development can continue without harming the environment and without reducing the quality of concrete," he explained. (*)