Energy Conservation Design Features of the ARCO Metals Logan County Aluminum Process Complex

Abstract

ARCO Metals Company (Formerly Anaconda Aluminum Company) is proceeding as scheduled with the construction of a $400 Million aluminum processing complex in Logan County, Kentucky. When the initial construction phase is completed in the Fall 1983, the complex will be capable of producing 400 million pounds per year of aluminum, sheet and foil using highly automated, computer controlled equipment that will maximize end product quality and minimize the consumption of energy.

This paper will describe the basic processes used in the Logan complex and several design features that are being incorporated to reduce energy consumption.

Large reverberatroy melting furnaces will remelt scrap aluminum and ingots will be cast on site to supplement those delivered to the site from ARCO Metal's reduction plants. The melting furnaces are expected to achieve a high efficiency which will be further enhanced by the utilization of exhaust gases to preheat the scrap as well as the combustion air. A coreless induction furnace will be used to reduce the melt loss normally associated with light gauge scrap.

The ingots will be heated prior to rolling in the hot mill in direct fired preheating furnaces with variable speed fans that minimize cycle time. Flue gasses from these furnaces will be used to generate steam In a waste heat boiler.

Motor loads in the hot mill and cold mills, along with other electrical loads, will be monitored by a computer system to minimize peak loading on the TVA power system.

Annealing of aluminum coils will be accomplished in radiant tube furnaces with variable speed fan drives in an inert atmosphere produced by an electric powered air separation plant. These furnaces will use recuperative burners.

The HVAC system incorporates a feature that will recover stratified hot air for use in other parts of the complex for ambient temperature control.