TY - BOOK

T1 - A Breakage Model for Discrete Element Simulations Applied to Iron Ore Sinter

AU - Denzel, Michael

N1 - no embargo

PY - 2023

Y1 - 2023

N2 - Due to mechanical stress during transport and storage, bulk material partly degrades and fines are produced. This can be problematic in various applications and is especially critical for blast furnace sinter. Fines have to be re-sintered and are responsible for additional high costs, energy demand and emissions. To analyze breakage behavior of blast furnace sinter a highly automated test rig for rapid single particle impact testing with integrated fragment analysis was developed. Fragment size distribution, fines production and breakage probability were investigated and clear trends were able to be determined. A general fines production curve was able to be calculated by introducing a size factor. A size-independent description with the tn-model was also performed. Neither a post-processing procedure nor bonded particle models were considered suitable to simulate the degradation of blast furnace sinter during transport and storage processes. A novel breakage model for the discrete element method using polyhedral particles is presented. The breakage model is based on a probabilistic particle replacement with Voronoi-tessellated fragments. In contrast to other particle replacement models with spheres, mass and volume remain constant. High mass flows and multiple breakage for processes with several damaging events, as found in industrial applications, can be simulated. The breakage model was verified and validated by a series of shatter tests and trials with two different transfer systems with different batches of sinter from two different manufacturers. Simulation and test results are consistent. Especially the fines are predicted with high accuracy. The breakage model was successfully applied to quantify particle breakage in a solid state material turbine used to reduce segregation effects during bunker filling.

AB - Due to mechanical stress during transport and storage, bulk material partly degrades and fines are produced. This can be problematic in various applications and is especially critical for blast furnace sinter. Fines have to be re-sintered and are responsible for additional high costs, energy demand and emissions. To analyze breakage behavior of blast furnace sinter a highly automated test rig for rapid single particle impact testing with integrated fragment analysis was developed. Fragment size distribution, fines production and breakage probability were investigated and clear trends were able to be determined. A general fines production curve was able to be calculated by introducing a size factor. A size-independent description with the tn-model was also performed. Neither a post-processing procedure nor bonded particle models were considered suitable to simulate the degradation of blast furnace sinter during transport and storage processes. A novel breakage model for the discrete element method using polyhedral particles is presented. The breakage model is based on a probabilistic particle replacement with Voronoi-tessellated fragments. In contrast to other particle replacement models with spheres, mass and volume remain constant. High mass flows and multiple breakage for processes with several damaging events, as found in industrial applications, can be simulated. The breakage model was verified and validated by a series of shatter tests and trials with two different transfer systems with different batches of sinter from two different manufacturers. Simulation and test results are consistent. Especially the fines are predicted with high accuracy. The breakage model was successfully applied to quantify particle breakage in a solid state material turbine used to reduce segregation effects during bunker filling.

KW - Partikelbruch

KW - Diskrete Elemente Methode

KW - Hochofensinter

KW - Rückgut

KW - polyedrische Partikel

KW - Voronoi

KW - Fragmentgrößenverteilung

KW - Zerkleinerung

KW - Einzelpartikel-Prallversuche

KW - particle breakage

KW - discrete element method

KW - blast furnace sinter

KW - fines

KW - polyhedral particles

KW - voronoi tessellation

KW - progeny distribution

KW - comminution

KW - single particle impact test

U2 - 10.34901/MUL.PUB.2023.01

DO - 10.34901/MUL.PUB.2023.01

M3 - Doctoral Thesis

ER -