Authors: I. Gordon, M.E. Blank, V.V. Madison, P.R. Abovian
Proceedings of Asia Steel International Conference, Jamshedpur, India, April 2003
Abstract
High quality lime is an essential raw material for Electric Arc Furnaces and Basic Oxygen Furnaces steelmaking, alumina production etc. Decrease in fuel consumption in metallurgical furnaces is a tremendous opportunity for reduction of greenhouse gas emissions into the atmosphere. Developed by Hatch (Canada) and Ural State Technical University (Russia) the new environmentally friendly technology and the design of a shaft furnace for production of high quality metallurgical lime utilize the idea of the incomplete combustion of natural gas in special burners outside the furnace with following complete combustion of the rich fuel inside the layer of material. The furnace design incorporates the peripheral and central gas distribution devices located at two levels. One of the three shaft furnaces of Nikolaev Alumina Plant (Ukraine) was modernized according to this invention. The newly retrofitted furnace was commissioned three years ago and operates with the following results: the production rate has been increased by 33%, fuel consumption decreased by 40%, (CaO+MgO)active increased by 9% reaching up to 93-94%, yield increased by 5- 7%. Also the green house gases emission into the atmosphere have been decreased (g/Nm3): NOx - from 0.06-0.110 to 0.027-0.038, dust - from 0.6-5.0 to 0.4-0.9, CO from 12.5-25 to 0.03-0.47, SO2 – from 0.3-1.0 to 0 and CO2 emissions were decreased by 25%. The furnace operation exceeds all design parameters. Nikolaev Alumina Plant is finishing the retrofit a second shaft furnace.
