Studies on the cement-bonded briquettes of iron and steel plant by-products as burden material for blast furnaces
2002 (English)Doctoral thesis, comprehensive summary (Other academic)
During the various stages of iron and steel production a number of iron bearing by-products are generated. These by-products can be made into cement- bonded agglomerates for use as burden material for blast furnaces. In order to improve the quality of agglomerates, the effect of various processing parameters on the properties of cement-bonded briquettes has been studied. It has been found that the room-temperature properties of briquettes depend upon various processing parameters like solid / water ratio, vibration time, briquetting force, compression time and particle size distribution of the raw material. The study has also shown that the strength of briquettes decreases after heating in a nitrogen environment and after reduction. The strength of briquettes can be increased by increasing the amount of pre-reduced / flaky components, increasing the amount of cement and decreasing the particle size of the raw material. Under certain reducing conditions, the cement-bonded briquettes exhibit a tendency to swell catastrophically. This happens especially during the reduction of wustite to iron at 950oC using CO as the reducing gas. The briquettes that contain coarse pellet-fines particles are specially prone to swelling since the pellet-fines contains a large percentage of under-fired and weak fraction of the pellets. This swelling can be controlled by grinding the raw material finely, increasing the cement content, and adding calcium oxide / magnesia / silica or alumina to the cement. A model to describe the swelling process has also been propounded.
Place, publisher, year, edition, pages
Luleå: Luleå tekniska universitet, 2002. , 41 p.
Doctoral thesis / Luleå University of Technology 1 jan 1997 → …, ISSN 1402-1544 ; 2002:50
Research subject Process Metallurgy
IdentifiersURN: urn:nbn:se:ltu:diva-17763Local ID: 513a8350-7116-11db-962b-000ea68e967bOAI: oai:DiVA.org:ltu-17763DiVA: diva2:990769
Godkänd; 2002; 20061109 (haneit)2016-09-292016-09-29Bibliographically approved