Divide and conquer: Spectral-splitting and utilization of thermal radiation from waste heat in the steel industry

Haoming Li, Shuaibin Wan, Lu Wang, Jiyun Zhao and Dongxu Ji

Applied Energy, 2025, vol. 378, issue PA, No S0306261924022190

Abstract: Approximately 35 % high-temperature waste heat in the steel industry is carried by blast furnace slag and steelmaking slag, and thermal radiation is a primary pathway for this waste heat to dissipate into the ambient environment. Thermophotovoltaic (TPV) systems can convert short-wavelength thermal radiation into electrical energy, but the long-wavelength radiation is still wasted. Here, this work introduces a concept of spectral-splitting (SS) for full-spectrum thermal radiation utilization, allowing simultaneous waste heat recovery by TPV and heat-to-power methods such as Stirling engine (SE). To further demonstrate this concept, an SS TPV-SE system is designed. An optical transmission window of 0–1.7 μm is applied for TPV, and an over 5 μm absorption window is applied for SE. Results show that, with a 0.1 × 1 m molten slag chute, the SS TPV-SE system yields an output power of over 1300 W and achieves an overall efficiency of around 19 %, resulting in an about 58 % improvement compared to the standalone TPV system, and leads to a CO2 emission reduction of 7516 kg/year. Provided the improved energy efficiency and environmental sustainability, the spectral-splitting concept presented in this work provides a promising approach to enhancing waste heat recovery in the steel industry.

Keywords: Molten slag; Heavy industry; Spectral-splitting; Thermophotovoltaic; Waste heat recovery (search for similar items in EconPapers)
Date: 2025
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0306261924022190
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:appene:v:378:y:2025:i:pa:s0306261924022190

Ordering information: This journal article can be ordered from
http://www.elsevier.com/wps/find/journaldescription.cws_home/405891/bibliographic
http://www.elsevier. ... 405891/bibliographic

DOI: 10.1016/j.apenergy.2024.124836

Access Statistics for this article

Applied Energy is currently edited by J. Yan

More articles in Applied Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().