Energy in alumina refining - setting new limits

ENERGY IN ALUMINA REFINING - SETTING NEW LIMITS

This Paper was presented during International Conference on Non-Ferrous Metal 2015 at Bhubaneswar, Odisha, India

Outotec

By: Alessio Angelo Scarsella, Sonia Noack, Edgar Gasafi, Cornelis Klett, Andreas Koschnick

Abstract

Enormous emphasis is placed on the specific energy consumption from the refining of alumina from Bauxite. The current spread of specific energy consumption of the industry varies from 7 GJ/tonne to 21 GJ/tonne. Energy consumption is highly technology specific with digestion and calcination accounting for sixty percent of refinery thermal energy consumption. With Greenfield projects placing a high importance on fuel consumption in order to make their projects viable, careful selection of the technology will have an immediate impact on the energy consumption and in turn the fuel consumption which could ultimately determine the financial viability of the refinery throughout the lifetime of the project.

This paper seeks to analyze the energy consumption requirements for different digestion and calcination configurations, such as single vs split stream digestion along with alternative methods of final stage heating; as well as calcination technology options and also their impact on the financial viability of the refinery itself.