Integrated coal-pyrolysis tar reforming using steelmaking slag for carbon composite and hydrogen production

• Published in: Fuel (Guildford) 2013-07, Vol.109, p.439-444
• Main Authors: Bakti Cahyono, Rochim, Rozhan, Alya Naili, Yasuda, Naoto, Nomura, Takahiro, Hosokai, Sou, Kashiwaya, Yoshiaki, Akiyama, Tomohiro
• Format: Article
• Language: English
• Subjects: Alternative fuels. Production and utilization; Applied sciences; Carbon; Carbon content; Carbon deposition; Coal; Coking plant; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fuels; Hydrogen; Iron and steel making; Pyrolysis; Reduction; Reforming; Slags; Steelmaking slag; Tar recovery
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2013.03.070

•Catalytic tar reforming over steelmaking slag to produce hydrogen and carbon material.•Steelmaking slag increased hydrogen gas product and carbon content within the slag.•High carbon deposition within slag was obtained at low temperature.•Beside tar decomposition, methane reforming occurred at temperature above 600°C.•This system offered energy saving 104.3MJ/ton steel in the steelmaking industry. Steelmaking slag contains high amounts of CaO, Fe2O3, SiO2, and Al2O3, and has great potential as a catalyst for the tar-reforming reaction to produce a carbon composite and hydrogen. This paper describes chemical waste-heat recovery of tar and the effects of slag on the tar-reforming reaction. The results indicate that slag has a good activity for decomposing tar into the gas phase and for producing high carbon content within the slag. The introduction of coal-pyrolysis products to slag at a temperature of 500°C caused an 18%vol increasing in the gas amount and a 6%mass enhancing in the carbon content within the slag compared to coal pyrolysis without slag. At higher temperatures, coal pyrolysis gave rise to lower carbon deposition within the slag but a higher amount of gas product. Moreover, the gas reforming reaction occurred simultaneously with tar decomposition at higher temperatures. This proposed system offers energy-saving benefits of 103MJ/ton steel and a 6%mass reduction in coke-breeze usage in the steelmaking industry.