Desenvolvimento de um sistema supervisório para o bombeamento de dreno de fundo

Abstract

In mining, the bottom drainage system is designed to remove water that accumulates at the bases of tailings dams or waste rock piles as a result of natural soil drainage. In gold mining, its main function is to drain the accumulated effluent, preventing the increase of internal pressure within the structure and reducing the risks of environmental contamination by pumping water from a drainage well back into the process and, subsequently, to the tailings dam. This work addresses the proposal for improvement of an existing bottom drainage pumping system in a gold mining operation, which originally operated with two pumps connected to a single pipeline responsible for returning the effluents to the dam. During periods of intense rainfall, the system proved unable to meet the required flow rate, resulting in effluent overflow and contact with the soil, characterizing an environmental risk scenario. Such conditions may lead to losses for the company, including legal penalties, financial impacts, damage to reputation, and non-compliance with current environmental legislation. Given this context, it became necessary to develop a system improvement project, including the installation of an additional pump in order to increase pumping capacity. As part of this proposal, the present work aims to develop an automation and supervision solution for the bottom drainage pumping system, encompassing process modeling, definition of operational scenarios, implementation of control logic in a programmable logic controller (PLC), and the development of a supervisory control and data acquisition (SCADA) system. This solution is intended to provide real-time monitoring and control of the process, contributing to a more efficient operation.