Productivity and quality of pulverised coal for increasing blast furnace injections
During recent years, the injection of pulverised coal to the blast furnace experienced considerable industrial development. Presently, high coal injection issue has become more stringent, driven by strong energy economics, environmental considerations, cost and availability of coke, and preservation of coke oven lifetime. Modelling and testing of new coals in regards to their grinding and their injection are thus essential to ensure the expected flexibility and regularity. The present research aimed at: - investigating the performance of the coal injection processes; - developing testing procedures to evaluate the behaviour of various coals. The main outcomes and further applications in European grinding plants can be summarised as follows: - all the industrial trials, performed on various kinds of grinders (horizontal ball mills and vertical ring roll mills) and classifier devices (static or dynamic), exhibited the major role of the classifier devices to control the pulverised coal size when changing the production rate and/or the single coal or coal blend. Each company deduced from these trials operational rules for the operators; - first modelling of a ball mill gives promising results in terms of relationships between raw coal characteristics, grinding conditions and pulverised coal quality; further investigations are still necessary to accurately determine some input data in order to use the model in a predictive way; - some of the tested laboratory techniques are clearly promising, and show that the main factors affecting coal handling are moisture, particle size distribution, hardness, mineralogy and fraction of mineral matter. Such tools and methods should enable operators to select coals with optimum handling properties and to develop strategies for minimising grinding and transportation problems.
Bibliographic Reference: EUR 21728 EN (2005), 191 pp. Euro: 25
Availability: http://bookshop.europa.eu/is-bin/INTERSHOP.enfinity/WFS/EU-Bookshop-Site/en_GB/-/EUR/ViewPublication-Start?PublicationKey=KINA21728 (Catalogue Number: KI-NA-21728-EN-S)
ISBN: ISBN 92-894-9874-9
Record Number: 200618443 / Last updated on: 2005-12-15
Original language: en
Available languages: en