TY - THES

T1 - Correlation of evaluation methods of iron ore pellets with their performance in a direct reduction plant

AU - Schwarz, Gero

N1 - embargoed until 24-08-2023

PY - 2018

Y1 - 2018

N2 - This thesis analyzes the evaluation methods of iron ore pellets in the Midrex process and examines the performance of six different pellet types under industrial conditions. The performance of the different pellet types in the furnace was based on industry data and a series of mass balances used to calculate process parameters reflecting pellet performance. Eleven different cases of different raw material mixes were analyzed, and the performance of six pellet types was calculated. These calculations were then compared to the available standardized test results (ISO 11257 and ISO 11258). While the ISO 11257 showed some correlation to the furnace performance, no correlation was observed regarding the ISO 11258. A chemical and thermal profile of the furnace was calculated to relate the test parameters to industrial conditions. The incoming gas and iron oxide composition and flow was taken from industrial data and the reaction rate was calculated based on reduction tests performed at different gas compositions. The resulting profile was compared to six standardized reduction tests and both temperature and gas profiles show the highest similarities with the R180 test. Based on the calculated reduction profile of the furnace, the R180 test is slightly modified to even closer resemble the furnace conditions. Apart from a temperature profile change, this includes adding water to the gas composition. The results show a correlation between the industrial furnace performance and the test, but also show potential for further improvement.

AB - This thesis analyzes the evaluation methods of iron ore pellets in the Midrex process and examines the performance of six different pellet types under industrial conditions. The performance of the different pellet types in the furnace was based on industry data and a series of mass balances used to calculate process parameters reflecting pellet performance. Eleven different cases of different raw material mixes were analyzed, and the performance of six pellet types was calculated. These calculations were then compared to the available standardized test results (ISO 11257 and ISO 11258). While the ISO 11257 showed some correlation to the furnace performance, no correlation was observed regarding the ISO 11258. A chemical and thermal profile of the furnace was calculated to relate the test parameters to industrial conditions. The incoming gas and iron oxide composition and flow was taken from industrial data and the reaction rate was calculated based on reduction tests performed at different gas compositions. The resulting profile was compared to six standardized reduction tests and both temperature and gas profiles show the highest similarities with the R180 test. Based on the calculated reduction profile of the furnace, the R180 test is slightly modified to even closer resemble the furnace conditions. Apart from a temperature profile change, this includes adding water to the gas composition. The results show a correlation between the industrial furnace performance and the test, but also show potential for further improvement.

KW - Direktreduktion

KW - Midrex

KW - Reduktions Tests

KW - Direct Reduced Iron

KW - Midrex

KW - Iron Ore Reduction Test

U2 - 10.34901/mul.pub.2023.268

DO - 10.34901/mul.pub.2023.268

M3 - Master's Thesis

ER -