Utilization of Waste HDPE for Sustainable EAF Steelmaking: Carbon Dissolution into Liquid Steel. Issue 1 (12th August 2016)

• Record Type: Journal Article
• Authors: Kongkarat, Somyote; Cherdhirunkorn, Benya; Thongreang, Raumporn
• Is Part Of: Steel research international. Volume 88:Issue 1(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2016-08-12
• Subjects: carbon dissolution -- steelmaking -- waste HDPE -- recycling; Steel -- Periodicals; Steel -- Metallurgy -- Periodicals; 669.142
• DOI: 10.1002/srin.201600168
• Languages: English
• ISSNs: 1611-3683

Abstract

Abstract : Carbon dissolution from blends of metallurgical coke with high‐density polyethylene (HDPE) into liquid steel at 1823 K is investigated in‐depth. HDPE is blended with metallurgical coke into three different ratios (blends H1, H2, and H3) and used as a carburizer. Compared to coke, a significant improvement in carbon dissolution is observed in the case of blend H3 with the carbon picked up by liquid steel after 60 min of reaction and the dissolution rate ( K ) is 4.5 wt% and 15.2 × 10 −3 s −1, respectively. For coke alone, the melt carbon content is 0.8 wt% and the dissolution rate of 0.3 × 10 −3 s −1 . SEM micrographs and corresponding off‐gas analysis reveal that the gasification of HDPE/coke blends slow down the coverage of ash oxides at the Fe–C interface and modify morphology of the ash layer. The associated reactions of volatiles generated during the thermal degradation of the polymer can aid the carburization of liquid steel to some extent. However, the amount of gas generated must be high enough to overcome the effect of ash oxides at the Fe–C interface. This study has strong implications in enhancing the potential of recycling waste polymers for sustainable steelmaking. Abstract : Blends of HDPE with metallurgical coke are used as a carburizing material in EAF steelmaking. The blend can significantly enhance the dissolution of carbon into liquid steel compared to pure coke, but this strongly depends on HDPE concentration in the blend. Blend H3 shows the overall carbon dissolution rate of 15.2 × 10 −3 s −1, whereas it is 0.3 × 10 −3 s −1 for coke alone.