In the demanding world of mining, water conservation and equipment reliability are two sides of the same coin. Now, a groundbreaking retrofit project led by John Crane is proving that upgrading a single piece of critical equipment can yield massive environmental and operational benefits. By replacing a traditional sealing arrangement on a heavy-duty slurry pump, the company has helped a major open-pit copper mining operation cut its sealing water consumption by an astonishing 288,000 liters per day.
The Challenge: High Water Use and Heavy Maintenance
At the heart of the mine’s tailings circuit is an underflow thickener slurry pump—specifically a Warman 550—tasked with transporting high-density tailings slurry at a grueling 65% solids concentration. Previously, this pump relied on a traditional stuffing box packing arrangement.
However, the highly abrasive operating environment took a severe toll on the equipment. The pump’s shaft sleeve suffered significant wear, requiring a complete replacement every four months. These major maintenance interventions were incredibly resource-intensive, demanding a full mechanical crew working across two shifts, the deployment of a 100-tonne crane, and resulting in extended, costly downtime.
The Solution: A Seamless Mechanical Seal Retrofit
To solve the dual problems of excessive water use and frequent maintenance, John Crane engineered a seamless retrofit. The project involved replacing the old stuffing box with an advanced mechanical seal package and adapter sleeve, requiring absolutely no modifications to the existing pump housing.
To survive the harsh, abrasive conditions, the new sealing arrangement incorporates a controlled seal-flush system designed to maintain a pristine environment at the seal faces. Furthermore, diamond-faced materials were specified to provide ultimate durability and protect the seal in the event that flush pressure drops and abrasive solids breach the seal chamber.
Massive Water Savings and Operational Uptime
The results of the retrofit have been transformative for the mine’s daily operations. Following commissioning, the newly sealed system operates using just 7.5 to 8 m³/h of sealing water, a dramatic drop from the 20 m³/h consumed by the previous packed pump.
This efficiency equates to a reduction of roughly 12 m³/h, saving approximately 288,000 liters of clean water every single day. Beyond the environmental and cost-saving benefits of the water reduction, the upgrade has virtually eliminated the need for those grueling four-month shaft sleeve replacements, drastically cutting maintenance exposure and maximizing pump uptime.
Industry Perspective
Warren Smith, Global Mining Market Director at John Crane, highlighted the significance of the project for the broader mining sector:
“Underflow thickener pumps are among the most critical assets in a mine’s tailings circuit, so customers are understandably cautious about change. This project is a practical example of how improved sealing can reduce maintenance exposure and cut the clean water required for sealing, while supporting more predictable planned maintenance.”
Looking Ahead
As the mining industry faces increasing pressure to optimize water usage and reduce operational footprints, John Crane’s successful retrofit serves as a powerful blueprint. It proves that targeted, intelligent upgrades to critical flow control equipment can deliver immediate, measurable returns in both sustainability and production reliability, ensuring that mines can keep pumping efficiently while preserving vital water resources.
