Modeling of burden and gas flow in the upper part of the blast furnace
- Tamoghna Mitra
- Åbo Akademi University
- Prof. Henrik Saxen
- Jan 2012 – Dec 2015
The main objective of the research is to gain understanding of the behavior of the burden at changing and during its descent in the blast furnace process. Different phenomena associated with blast furnace charging, like particle segregation, coke collapse and mixed layer formation are studied. Effect of different particle parameters like size, shape and type of material charged is taken into account. Cold models of charging and descent are used for verifying the computational models and for guiding parameters settings in the DEM.
The gas flow characteristics corresponding to different charging programs are also estimated by CFD and the thermal characteristics of the shaft are evaluated.
Simplified 2D online models for burden distribution and gas flow modeling have already been developed. Experiments using the pilot model of the burden charging system for different charging programs have been performed.
EDEM has been successfully used to simulate few charging programs. It has been useful to understand the behaviour of particle flow especially when the burden consists of particles of different shapes and sizes. In particular, complex dynamic effects, such as shifting of materials charged earlier (e.g., coke push) and percolation/sieving of smaller particles in a bed of larger particles are mechanisms that are extremely difficult to simulate by other methods.
In future coupling the DEM results with a CFD simulation would be crucial in modelling the complete phenomena and therefore EDEM would remain an extremely important tool.
Fig. 1. EDEM simulation of a charging program in the blast furnace consisting of three rings of coke and two rings of pellet - isometric view.
Fig. 2. Cross-sectional view (Green: large coke, blue: small coke, red: centre coke, grey: pellets).
EDEM has been a very useful tool for Discrete Element Modelling of the charging program in a blast furnace. The main advantage of the software is terms of ease of use and great technical support. Also, continuous updates over the time make the product extremely reliable and robust.