SmartSinter - Materialverfolgung von Schüttgut und dessen Eigenschaften

Research output: ThesisDoctoral Thesis

Organisational units

Abstract

Sinter is a dominant operational material for the blast furnace, with a continuous inhomogeneous material flow. Depending on the process step, different material flow structures (linear, converging, diverging, etc.) can be found in the material flow. In order to be able to describe such a material flow and its relevant attributes such as quality or other characteristics, a model concept was developed in this thesis and validated using the example of the sintering plant of voestalpine Stahl Donawitz GmbH. Sieves and conveyor lines can be easily observed and described in terms of material flow. Sinter coolers or bunkers in the stock house pose a challenge, as their interior cannot be observed. In order to examine the flow characteristics of these sub-areas, a physical bunker section model, bunker simulations (DEM - discrete element method) and tracer studies (RFID \& color tracer) were used in the operating facilities. A transitional function for the material flow was found for the cooler. This function describes the system’s response when input properties change. Due to the moderately prevailing product temperatures in the storage bunker area in contrast to the sinter cooler, the applicability of RFID technology in this area was examined. The use of the technology provides important information about the flow behavior in this sub-area. In the bunkers there is a pronounced core flow, which was confirmed with all three methods used. The DEM-simulation was able to quantify this core flow and also provided important information about the segregation process when filling and emptying the bunker. It was thus established that an originally uniform grain distribution after the bunker system must greatly fluctuate. From the wide range of possibilities to measure different good properties, this thesis concentrated on the strength indicators, grain size distributions, masses and volumes as well as chemical compositions. While masses can be easily tracked online using belt scales, qualified chemical analyses of the material flow can only be carried out using samples. If the sampling process is ideally designed, results are not immediately available and cannot be used for process control or quality monitoring. Online measurement techniques for determining the grain size distribution were investigated and the challenges of these systems were explained. The oberserved different chemical analyses in the individual grain classes and the findings from the bunker investigations can influence the downstream blast furnace process. The result of this thesis is a validated model concept that combines flow characteristics and good properties and can be used in other bulk materials industries such as mining, farming, the raw material industry, etc.

Details

Translated title of the contributionSmartSinter - bulk material tracking and its properties
Original languageGerman
QualificationDr.mont.
Awarding Institution
Supervisors/Advisors
Publication statusPublished - 2020