TD-DAQ: A low-cost data acquisition system monitoring the unsaturated pore pressure regime in tailings dams. (October 2021)

• Record Type: Journal Article
• Authors: Basson, Jack Adriaan; Broekman, André; Jacobsz, Schalk Willem
• Is Part Of: HardwareX. Volume 10(2021)
• Publication Date: 2021-10
• Subjects: Geotechnical instrumentation -- Soil mechanics -- Waste management -- Platinum tailings -- Soil water retention curve -- Unsaturated pore pressure regime -- Tensiometer -- Arduino -- Pycom -- SigFox -- Civiltronics -- IoT; Scientific apparatus and instruments -- Periodicals; Laboratories -- Equipment and supplies -- Periodicals; Laboratories -- Equipment and supplies; Scientific apparatus and instruments; Periodicals; Electronic journals; 681
• DOI: 10.1016/j.ohx.2021.e00221
• Languages: English
• ISSNs: 2468-0672

Abstract

Graphical abstract: Highlights: Successful realisation of a low-cost data acquisition system for geotechnical applications. Negative pore pressure, soil temperature and dielectric permittivity measurements. Integrated battery power and SigFox communications for remote operation. High level of customizability for adding additional sensors. Abstract: Tailings dams are large, often self-contained, storage facilities of mine residue. On self-contained tailings dams the tailings material itself is used to raise the containment embankments holding newly deposited residue. To develop the necessary strength, it is essential that material must dry out sufficiently. Despite substantial advancements in the field of instrumentation, these parameters are rarely measured on tailings dams and their evolution over time is poorly understood. Understanding the role of pore water suction and water content evolution over time can benefit from the installation of sensors and data acquisition systems (DAQ) capable of continuously monitoring these parameters. Such monitoring remains difficult and expensive owing to the challenges of measuring negative water pressures and the often-remote locations and harsh operating environments typical of mining operations. This paper describes the development, testing and validation of a low-cost DAQ for the measurement of the unsaturated pore pressure regime in a platinum tailings dam located in the Limpopo province of South Africa. The Tailings Dam DAQ (referred to as TD-DAQ) is designed to measure the negative pore pressure, moisture content and temperature in fine-grained material over extended periods of time. These measurements are stored on the DAQ and transmitted in parallel using new wireless network communications technologies (Sigfox) suited to remote, battery powered applications. The successful deployment of the TD-DAQ presents a real-time, low-cost instrumentation solution to improve the efficiency of condition monitoring of tailings storage facilities, contributing to a reduction in the probability of failure events.