Some traditionalists in the mining sector are still reluctant to adopt variable-speed drive (VSD) technology for their pump operations, despite VSD technology being more than 20 years old, says digitalisation and automation technology company Schneider Electric South Africa product manager Jaque Mare.

He says that VSDs have proven to contribute significantly to the lowering of energy consumption in pump applications, the importance of which has been highlighted by the economic pressures caused by Covid-19, as well as increased energy costs. These factors have led to an increased uptake of the technology in the mining pumps sector over the past two years.

Moreover, the need for sustainability, amid energy-intensive mining operations is increasingly being emphasised on the back of rising concern about climate change.

“Energy costs remain a prevalent factor in the total cost of ownership of industrial pumping systems. However, it is possible to reduce energy consumption by at least 30% if the appropriate energy management practices are put in place.”

The first step is to acknowledge the high energy costs of pump systems by introducing steps to implement cost reductions through efficiency improvements.

Mare adds that a lack of proper metrics is a key barrier to reducing energy costs.

He notes that Schneider Electric’s Altivar Process VSD provides digital metrics that can help to ensure better energy efficiency.

It was introduced to the market in 2016, with consistent upgrades.

Mare says another barrier is the continuing knowledge gap among users.

“The lack of awareness of energy efficiency opportunities is prevalent and, as a result, potential savings and benefits are missed.”

Moreover, fear of investment also means that operational personnel can sometimes struggle to explain to upper management and investors why paying 40% more for a VSD is a worthwhile investment over the medium to long term.

“What is required is the implementation of a sound energy management strategy, which features practical and attainable steps to address the reduction of the total cost of ownership while realising the benefits of an efficient pumping system,” Mare says.

The efficiency of pump systems can be affected by a mismatch between the size and strength of the pump deployed and the actual system requirement.

The improper use of throttling valves and damper technologies to control the flow of liquids can also impact on energy efficiency.

“These issues can be remedied by replacing fixed drives with VSDs,” Mare explains.

Moreover, when coupled with energy management software, such as Schneider Electric’s Internet-of-Things-enabled EcoStruxure, mines can more accurately manage their energy consumption across all pumps.