Improving sinter cooling efficiency by finding the optimal design by simulating complex particle systems

About the customer

ArcelorMittal is one of the world’s leading steel and mining companies, with a presence in 60 countries and primary steelmaking facilities in 17 countries employing more than 190,000 people. In a recent project, a large-scale charging chute of a sinter cooler plant in Fos-Sur-Mer, France had to be optimized by the ArcelorMittal research and development (R&D) team to improve the reliability and efficiency of this device. The objective was to identify a better and more feasible design that improved granular segregation, abrasion and mechanical resistance. The team used Simcenter™ EDEM™ software, a software based on the discrete element method (DEM), to gain a better understanding about the overall material behavior and the sinter cooling charging system. Simcenter is part of the Siemens Xcelerator business platform of software, hardware and services.

DEM simulation of a sinter cooler charging chute system – Edouard Izard (right).

Their challenge

To get a processible particle size, fine iron ores are agglomerated, fired on the sinter strand and cooled down in the sinter cooler before being crushed and sent to the blast furnace. During the charging of the hot material in the sinter cooler, particle segregation can occur, leading to several severe problems such as fire issues on conveyor belts and sinter quality issues. To investigate the segregation patterns, the impact of particle sizes and the effect of the filling ratio on the segregation patterns in the trolleys of the sinter strand, the R&D team had to find a suitable simulation method to analyze and optimize the particle flow. Since simulating granular flows in a large system compared to the particle size is complex and time-consuming, the R&D team had to set up a modeling strategy that allowed for a good balance between computational efficiency and physical realism.

The DEM simulation provided valuable insight into the granular flow in the charging chute and segregation patterns.

Our solution

ArcelorMittal’s R&D team used high-performance software for granular material simulation via Simcenter EDEM to simulate and analyze the granular flows in the charging chute. Providing pre-calibrated material models, using Simcenter EDEM enabled the engineers to create and calibrate their model to match physical experiments.

First, the engineers analyzed the segregation patterns in the trolleys of the sinter strand, which were in agreement with the experimental measurements at the plant. To find out whether finer materials would change the segregation pattern, they performed a sensitivity study using different particle sizes. The results of this analysis revealed that the size of the particles has no effect on the segregation patterns. In addition, to define the best charging practices with the DEM model to ensure even distribution, the team studied the effect of the filling ratio on granular flow patterns. The analysis of the flow pattern of coarse and fine particles showed that a large filling ratio leads to an even distribution, whereas a low filling ratio has a negative effect. Using the results of their studies, the engineers then virtually tested different charging chute scenarios to find a design that meets all requirements regarding capacity and mechanical resistance.

Using the DEM model of the charging system the team was able to study the effect of the filling ratio on granular flow patterns. (Images: ©ArcelorMittal)

Results

The DEM simulation provided valuable insight into the granular flow in the charging chute and segregation patterns, which is difficult and sometimes impossible to measure in experiments. Thanks to leveraging the fast and scalable compute performance of Simcenter EDEM, ArcelorMittal’s R&D team was able to simulate the complex particle system of the sinter cooler charging system and validate with plant data for segregation. The DEM model provided results that correlated well with the segregation measurements. Building a DEM particle model for agglomerate particles via a calibration procedure helped ArcelorMittal to define the best charging practices and change the charging chute design that acts on the segregation pattern in the trolleys.

“Using Simcenter EDEM enabled us to understand the material behavior and the charging system and, consequently, find an optimal design to improve sinter cooling efficiency,” says Edouard Izard, research engineer at ArcelorMittal.