Investigation of flow distribution in energy intensive aluminium production reduction cells: An exploratory study

Abstract

The process of making aluminium often involves electrolytic cells, also known as reduction cells. The reduction cell exhaust manifolds must achieve a steady distribution of exhaust from each cell in the network. This will prevent fugitive pollutants, which are harmful to both human and environmental health. While ducts are adjusted to achieve appropriate flow rates, they become asymmetrical over time. A few case studies available in the literature that discuss the flow distribution in an electrolytic cell, and almost none provide insight into the operational flow distribution of reduction cells in service. As part of this study, the operating flow distribution in service reduction cells is examined, determined which factors contribute to poor gas patterns produced by reduction line cells and analysed the flow conditions that result in sediment deposition within the ducting that connects the reduction cells to the superstructure, which is the novelty of this case study. Various instruments were used to record the temperature and pressure of a smelting facility. Flow information for each cell was collected using Pitot traverses. Infrared thermography of the ducts was used to locate temperature anomalies and possible areas of particle build-up. These tests indicated a number of probable contributing causes that have contributed to the inadequate airflow pattern from each reduction cell.