Smelting aggregate

In March 2013 TMS International started processing material stored at the mill’s (currently ArcelorMittal Poland S.A.) dumping ground. The operation involves a mobile processing line which is located on the reclaimed part of the former yard. We manufacture road aggregate of various types and flexibly adjust our supply to customers’ needs. Other fresh slag is delivered in railway cars from ArcelorMittal Poland S.A. to TMS International where it is processed with the second Metal Recovery Plant. The final product of our manufacturing process are four types of aggregate.

They are marketed and sold as high quality steel and blast furnace aggregate.

Converter slag

It is also called steel slag and it is produced in converters during smelting process when pig iron is converted into steel. Converter slag is processed into road aggregate or grit used to manufacture mineral and asphalt mass. This slag is usually compact and dark grey in colour. It also looks like basalt. It has large specific and bulk density, compression strength, roughness and low water absorption. Smelting slag from various sources has undergone numerous tests to determine its radioactivity. They confirm that there are no limitations for smelting slag use in road construction industry or even in residential/commercial/industrial constructions. Analysis of hot water extracts indicate that slag can even be released to surface water and ground, excluding very alkaline water and ground. According to environmentalists high pH value does not give ground to negative assessment of the aggregate as its high alkaline value limits mobility of metals, including heavy metals.

Blast furnace slag

It is produced in a blast furnace during reduction of metallic iron. This slag is rough, coarse and light-grey to grey in colour. It can take any form from compact to pervious. It is also fine-crystaline or amorphous. Crushed slag forms regular shape grain aggregate with numerous sharp edges. Blast furnace slag aggregate is lighter in weights than natural aggregate. It is fire resistant and has good insulating properties. Due to its perviousness, its water absorption is higher than in case of natural materials. But as a result of closed porosity where air bubbles are not interconnected, BF slag has a very good frost resistance.