CIVS ME Graduate Research Assistants Successfully Defended Master’s Thesis

Congratulations to CIVS Graduate Research Assistants, Abdul Mateen Mohammed and Mohammadhossein Alimohammadi, on successfully defending their Master’s Thesis’s on July 17.

Mateen and Mohammadhossein will receive their Master of Science in Mechanical Engineering degree from PNW. Their research was conducted at CIVS under the supervision of CIVS Director Prof. Chenn Zhou, Professor by Courtesy at Purdue University’s School of Mechanical Engineering.

Mateen presented “Computational Study of Iron Ore Fines Reduction with Microwave-Generated Hydrogen Plasma”. Traditional ironmaking relies on carbon-based reduction of iron ore, making it the primary contributor of CO2 emissions in the steel industry. 70% of iron made globally is manufactured by the blast furnace process that utilizes coke along with carbon-based fuels. Alternative ironmaking processes like direct reduction are being explored to mitigate these emissions through the use of hydrogen gas as a reducing agent. Recent technological improvements have been made in hydrogen reduction processes, mainly in the development of low temperature hydrogen plasma technology which can accelerate the chemical reduction of iron oxides. The advantage of generation of plasma at low process temperatures perfectly aligns with the rotary kiln furnace’s strict thermal control requirements and promotes the use of iron ore concentrates. The use of ore fines further helps in cutting emissions by eliminating the energy intensive ore pelletizing step. This study aims to use Computational fluid dynamics (CFD) for modeling and simulation of the behavior of microwave plasma as an iron oxide reductant. The model will simulate heat transfer, mass transfer, and chemical reactions within the domain, while employing the Eulerian multiphase approach to capture the interactions between ore fines and gas. Both molecular and atomic hydrogen take part in reduction of iron oxides, with differing reaction kinetic and rates. The CFD model is validated against experimental data from laboratory-scale low temperature microwave plasma reduction experiments conducted with a single microwave plasma applicator under varying gas compositions by researchers at University of Illinois Urbana-Champaign (UIUC). The model is then applied to simulate a larger lab scale rotary kiln furnace which is being tested at Argonne National Lab (ANL) to aid in development and scale-up of the microwave plasma reduction technology.

Mohammadhossein presented “CFD Investigation of Hydrogen Injection Limits in an Ironmaking Blast Furnace”. While most of the global steel production is carried out via the blast furnace route, it remains the largest source of carbon dioxide (CO2) emissions in the steel industry. Blast furnace injectants can partially replace coke combustion, helping to reduce emissions, however, there are limits to the maximum levels achieved in practice. Natural gas (NG) and hydrogen (H2) injections, for example, have a strong quenching effect on the furnace shaft. Preheating injected gases can offer some mitigation of this effect, but for NG, excessive preheating leads to thermal decomposition, presenting other practical challenges. In comparison, preheated H2 or syngas could be delivered at the higher temperatures necessary to counter the quenching effects and directly replace more coke in the blast furnace. At the Center for Innovation through Visualization and Simulation (CIVS) at Purdue University Northwest (PNW), a comprehensive CFD model of the blast furnace has been developed to accurately predict the impacts of reduction, fuel injection, and gas distribution on operational performance. This modeling framework consists of two coupled sub-models: a commercial-code modeling approach using ANSYS Fluent to simulate the tuyere and raceway region (called the Fluent Integrated Raceway Model or FIRM), and an in-house Fortran CFD blast furnace shaft model that simulates the upper furnace where reduction reactions occur. As tuyere-level injection strongly influences the raceway region, accurately capturing its effects requires a comprehensive model equipped with advanced reaction mechanisms. This study details the newly developed 3D raceway model using commercial CFD code. The results highlight enhanced prediction capabilities of flow, combustion, and heat transfer phenomena in the lower furnace, providing an improved approach for evaluating injection strategies and supporting decarbonization efforts in ironmaking. Using the FIRM model results, a series of reducing gas injection cases is evaluated with the in-house shaft model to assess the maximum stable hydrogen rate under different preheating temperatures, prior to the onset of operational instability, while also quantifying the associated CO2 emission reduction.