Analysis of pressure gauge reliability in highly caustic alumina precipitation process- A case study

Alumina refineries are asset and energy intensive process facilities that reform bauxite ores into alumina. Commonly used process to produce alumina is Bayer Process. In each phase of this process reliable pressure monitoring plays a significant role to ensure energy and resource efficient safe and sustainable operation. In this research, a case study from a world class alumina refinery's alumina precipitation area is presented to highlight the failure of a reliable pressure monitoring system and how it contributes to high asset maintenance costs, production loss, and health, safety and environmental issues. A success story of successful enhancement of service life of economically non-repairable pressure gauge is discussed in this paper. The paper demonstrates how an innovative robust approach of gauge installation significantly eliminated the failure of a critical component of the pressure gauge, pressure sensing diaphragm seal, which led to a service life improvement of multiple times i.e. from few weeks to years. The research applied Root Cause Analysis methodology to identify the root causes of the failure and developed a key action list to solve the problem. In addition, life data analysis technique was used to evaluate the improvement in service life.