What is holistic mine water management? And why should miners approach water management holistically? Global mine water & slurry pumping and dewatering major Xylem argues that years of on-site experience have shown that smart and efficient management of all water processes across the mine site will enhance the reliability, sustainability and ultimately, productivity of a mine operation. “When managed in the right way, every water process – from sourcing to dewatering to treatment and reuse – can be transformed from an expense to a strategic advantage.”
A poll of mining operators carried out by Xylem revealed that 63% agree that the growing cost of water and sustainable water management is their most pressing water-related issue on site. Jessy Parmar, Business Development Manager for the Industrial Marketing team at Xylem told IM: “Clearly it makes economic sense to use this finite resource carefully and efficiently. Similarly, investors and regulators are increasingly focused on how mining companies manage water. The good news is there are several readily achievable steps you can take to efficiently manage mine water on site. From powerful and reliable pumping systems to smart technologies that automate processes, there is a wide range of supports available.”
Xylem says the first step it always advises is an audit of a mine’s total water management system. Parmar says this is a five stage process to ensure that a solid water management foundation is in place:
Perform a pumping system audit
How are pumps operating relative to their Best Efficiency Point (BEP)? Are pumps sized properly? Would a different type of pump perform more effectively for the application? How are piping, valves and controls performing on site? A golden rule of all pumping systems, including dewatering systems, is ensuring that each pump in the system is operating as close as possible to its BEP. This is the crucial first step to a reliable and efficient dewatering system with minimal downtime
Optimise pump energy consumption for enhanced BEP performance
Prime candidates are pumps that move large volumes of water over long distances or to much higher elevations. Ensure that air releases are installed to prevent the trapping of air at high points in the line. Non-return valves ensure the same water is not pumped repeatedly while also preventing backflow which is catastrophic to a pump’s resilience – based on the velocity of the backflow an impeller can be stripped from the pump shaft. It is also important to ensure pumps are not snoring
Optimise total cost of ownership
Sizing your pump to operate as close to the BEP in conjunction to optimising the design of the hydraulic parts will tremendously reduce wear and energy consumption which is directly related to cost savings. Having the appropriate equipment in place with an effective maintenance schedule allows you to achieve long service life with a low cost of ownership resulting in overall peace of mind. Standardisation with the aid of devices such as variable frequency drives (VFDs) can also help control costs
Optimise the system
Technology – such as VFDs, PLC controls and SCADA systems – can be a major enabler to ensuring that the entire pumping system performs at the highest efficiency level, delivering the performance required, at low costs for energy and maintenance, and with the bare minimum of unplanned downtime. Such technologies with remote monitoring capabilities also support effective use of resources- staff and time
Contingency planning/emergency response
Finally, an optimised system includes built-in protection against downtime caused by equipment failure. The first line of defence is effective monitoring and maintenance. However, the most critical equipment requires contingency planning and emergency backup such as redundant or replacement pumps
Parmar continues: “Once you are confident you have the right pumping solutions in place, and each system is optimised, layering in smart technology can bring site efficiency, reliability and productivity to the next level. But how should you embark on introducing smart tech to your operation? Bearing in mind that a customised approach adapted to an individual mine’s operating conditions delivers maximum benefit, it can be helpful to look at a hypothetical scenario: let’s take an open pit mining operator looking for an efficient dewatering solution. The first step is to develop a customised solution using the most efficient dewatering pump to meet the head/flow requirements of the application. The pump should be paired with a variable frequency drive (VFD) to ensure optimal performance. As the mine expands and dewatering requirements increase additional pumps may be needed. This second phase of integrating smart technologies could involve a PLC intelligent controller such as the Flygt Multismart being incorporated into the system. This would enable the customer to easily control multiple pumps via the PLC or intelligent controller.”
He adds: A third phase would involve enhancing the dewatering system further by adding a remote M&C solution. Xylem’s Flygt cloud-based SCADA system connects to the Multismart control and allows the customer to monitor and control activity remotely. For isolated or inaccessible mine sites or operations where manpower is limited, remote monitoring and control (M&C) provides visibility of assets, and peace of mind, 24/7.”
Smart dewatering solution in Peru copper mine
Xylem devised a similar system for operators of a large open-pit copper mine in Peru – a smart dewatering solution to support the operation during a forthcoming rainy season. The Xylem team installed Godwin surface-mounted diesel-driven pumps operated by a remote M&C system. “Connected to the mine’s SCADA system the M&C solution can remotely start and stop the pumps, monitor capacity and fuel levels, and communicate operating parameter data to mine staff. Mine operators can now monitor and control the pumps’ flow and operation in just a matter of seconds when the pump is approaching maximum capacity or in advance of anticipated heavy rain events. Previously, reconfiguring pumps required retrieving the power cable and disconnecting hoses. The new proposed solution – with its remote monitoring capability – increased safety and efficiency and reduced labour costs associated with switching pumps or running electrical power down into the mine.”
The COVID-19 pandemic has accelerated the adoption of digitalisation across many sectors and mining is no exception. “Limited staffing resources and the enhanced safety that automation brings will see the use of intelligent pumping solutions, remote monitoring and controls and advanced telemetry systems increase rapidly in mining operations across the globe. And this can only be a good thing, enhancing efficiency, reliability and productivity across the sector. Now is the time to embrace automation and all its benefits and turn water management from an expense to a strategic advantage.”
