Current Affiliation Organization 【 display / non-display 】

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• Characterization of Char derived from Solid Waste for Fuel Recovery and Thermal Pretreatment before Landfilling

  2006.09

Published Papers 【 display / non-display 】

Published Papers 【 display / non-display 】

• EVALUATION OF CARBON STABILITY AND ENVIRONMENTAL SAFETY OF GARDEN WASTE-DERIVED HYDROCHAR

  Takumi ISHIKAWA, In-Hee Hwang, Piyumi Ayesha Hansani THENNAKOON WICKRAMASINGHE, Yasumasa TOJO, Takayuki MATSUO

  Japanese Journal of JSCE ( Japan Society of Civil Engineers )  82 ( 25 )   2026 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

• Distributed activation energy model (DAEM)-Based kinetic study on RDF pyrolysis and RDF-derived char combustion under N2 and CO2 atmospheres

  Ahmed Abd Alraheem Suliman Esaa, In-Hee Hwang, Yasumasa Tojo

  Chemical Engineering Journal ( Elsevier BV )  547   180536 - 180536   2026.11 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

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    DOI

• Pathway selection in cement hydrate assembly via transient calcium coordination by triethanolamine

  Qi Zhai, Tomoya Yamazaki, Hegoi Manzano, Hendrik Heinz, Yuki Kimura, Jiesul Park, Muhammad Haseeb Zaheer, Namkon Lee, Yuzo Miyazaki, In-Hee Hwang, Kiyofumi Kurumisawa, Juhyuk Moon

  Cement and Concrete Research ( Elsevier BV )  207   108293 - 108293   2026.09 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

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• Discovering the impact of triethanolamine (TEA): how TEA dosage transforms blast-furnace slag cement hydration

  Qi Zhai, Juhyuk Moon, In-Hee Hwang, Chi-sun Poon, Kiyofumi Kurumisawa

  Construction and Building Materials ( Construction and Building Materials )  491   2025.09 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

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• Computational-fluid-dynamics simulation of nitrogen oxide emission in a vertical-type waste incinerator under oxyfuel- and air-combustion conditions

  Ahmed Abd Alraheem Suliman Esaa, In-Hee Hwang, Yuki Ogaya, Takeshi Yamauchi, Yasumasa Tojo

  Waste Management ( Waste Management )  203   114860 - 114860   2025.07 [ Peer Review Accepted ]

  Type of publication: Research paper (scientific journal)

  　View Summary

  Oxyfuel combustion can significantly enhance carbon capture; however, its effects on NOX emissions are not yet fully understood in municipal solid waste (MSW) incineration. In this study, NOX generation in a vertical-type waste incinerator under air- and oxyfuel-combustion conditions was investigated using a combined experimental and computational-fluid-dynamics (CFD) modeling approach. Pyrolysis and combustion experiments were conducted using refuse-derived fuel (RDF) to determine NOX precursors. Thermogravimetric analysis (TGA) was employed to quantify the thermal degradation behavior and determine the kinetic parameters of RDF and char. Gas chromatography analysis identified NH3 and HCN as the dominant NOX precursors, which were subsequently used in modeling NOX formation. The Kilpinen-97 reaction mechanism was implemented in COMSOL Multiphysics to simulate NOX formation in a zero-dimensional (0D) waste bed model and a two-dimensional (2D) combustion and recombustion chamber model. The results revealed that oxyfuel combustion significantly reduced NOX emissions by 12% compared to air combustion. This reduction was primarily attributed to the higher CO concentration under oxyfuel conditions, which enhanced NOX reduction through radical-driven reactions. Moreover, the 2D CFD model predicted lower NOX emissions than the 0D model, highlighting the impact of carbon dioxide's physical properties on the flue gas mixing quality. Overall, these findings emphasize the potential of oxyfuel combustion to reduce NOX emissions and promote carbon capture in waste-to-energy plants, thus presenting a promising pathway toward more sustainable waste management.

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• Utilization of biochar derived from garden waste as a soil conditioner for carbon recycling and carbon sequestration

  T.W.P.A. Hansani, In-Hee Hwang, Takumi Ishikawa, Takayuki Matsuo, Yasumasa Tojo

  第37回廃棄物資源循環学会研究発表会  (北海道大学工学部)  2026.09  -  2026.09 

• Component-resolved DAEM kinetic modeling of RDF pyrolysis and char combustion under air and oxy-fuel atmospheres

  Ahmed Abd Alraheem Suliman Esaa, In-Hee Hwang, Yasumasa Tojo, Kengo Masuda

  第37回廃棄物資源循環学会研究発表会  (北海道大学工学部)  2026.09  -  2026.09 

• Distributed Activation Energy Model (DAEM)-Based Kinetic Study on RDF Pyrolysis and Char Combustion under Air and Oxyfuel Atmospheres

  AHMED ESAA, In-Hee Hwang, Yasumasa Tojo

  第32回衛生工学シンポジウム  (北海道大学フロンティア応用科学研究棟)  2025.11  -  2025.11 

• Numerical Study on NOx Reduction in Vertical-Type Waste Incinerators under O2/CO2 Combustion (Keynote Speech)

  In-Hee Hwang

  The 4th International Electronic Conference on Processes: Sustainable Process Design, Engineering, Control, and System Innovation (Online)  2025.10  -  2025.10 

• Improvement of heavy metals concentration in fly ash from melting facility for resource recovery at smelting industry

  Fukuda Motoki, Tojo Yasumasa, Hwang In-Hee, Matsuo Takayuki, Hosho Fumiki, Shibata Toru, Sakanakura Hirofumi

  Proceedings of the Annual Conference of Japan Society of Material Cycles and Waste Management  2025.09  -  2025.09 

  CiNii Research

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Grant-in-Aid for Scientific Research 【 display / non-display 】

Grant-in-Aid for Scientific Research 【 display / non-display 】

• Carbon recycling and carbon sequestration by the hydrothermal carbonization of waste biomass

  Grant-in-Aid for Scientific Research(C)

  Project Year: 2024.04  -  2027.03 

• Elucidation of NOx reduction mechanism in vertical stoker type incinerator and its application for NOx removal from solid waste incineration flue gas

  Grant-in-Aid for Scientific Research(C)

  Project Year: 2018.04  -  2022.03 

  Investigator(s): Hwang In-Hee 

  　View Summary

  Vertical stocker type incinerator is a novel incinerator which performs efficient incineration with forming drying, pyrolysis, and combustion zones vertically in the waste layer. However, the operation experience of vertical stocker type incinerator is not long so its characteristics are not well-known. In this study, we focused on the self-denitrification reaction of NOX in the reducing atmosphere of the waste layer from the viewpoint of NOX removal in the exhaust gas in the vertical stoker type incinerator. The generation characteristics of NOX, HCN, and NH3 in the waste layer and the effects of oxygen concentration, temperature, coexisting combustible gases, etc. on the oxidation or reduction of HCN and NH3 in combustion chamber were clarified by the gas concentration measurement in an operating vertical stocker type incinerator, lab-scale experiments, and combustion simulation.

• Evaluation of Integrated waste management system based on MBT concept for municipal solid waste

  Grant-in-Aid for Scientific Research(B)

  Project Year: 2017.04  -  2020.03 

  Investigator(s): Matsuto Toshihiko 

  　View Summary

  MBT is a combination of mechanical, biological, and thermal process as an integrated system. Two MBT systems were studied: combined system of Anaerobic Digestion (AD) and incineration, and Biodrying MBT which is followed by mechanical separation to recover solid fuel. Field study was conducted in real-scale facility, where solid waste and output material were sampled, and material balance and energy balance were clarified. Lab-experiment of biodrying was also carried out to construct moisture removal model. By taking two other system, incineration and RDF production system, four systems were evaluated in terms of energy recovery and CO2 emission. By using data obtained in our study and from literature review, material flow were drawn, and energy balance was estimated. Finally, sensitivity analysis of main parameters was carried out to find factors which should be improved for higher energy recovery rate.

• Grant-in-Aid for Scientific Research(C)

  Project Year: 2015.04  -  2018.03 

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