Investigating Applications of Heat Recovery Systems in Aluminum Smelters in the UAE

Abstract

Around 80% of the world total energy consumption is mainly derived from fossil fuels including coal, oil and gas. The great dependency on these non-renewable resources contributes to the generation of greenhouse gases (GHGs) which derive the climate change. Since the development of renewable energies, the global renewable power capacity has reached 1,179 gigawatts according to IRENA and 75% reduction of GHGs could be achieved through using these sources. The United Arab Emirates is one of the largest energy consumers per capita, and about 20% of the country’s total energy production is consumed by the aluminum industry. Around half of the energy input in the aluminum industry is lost as heat. The adoption of renewable energy sources and recovery of waste heat in aluminum industry would result in decreasing the overall cost, reducing greenhouse gas emissions and increasing the overall efficiency of the process. This paper presents a review and evaluation of waste heat-to-power conversion systems. The most appropriate system is selected based on the efficiency and the characteristics of the waste heat from the sidewalls of aluminum smelter. The integration of RE could be achieved through production and power modulation. The potential of heat waste recovered from the sidewall of a smelter cell, and its conversion into electricity is estimated. The resulting power efficiency improvement for the cells of a smelter operating with power modulation is estimated to reach 5.8%.