The John Crane slurry pump retrofit has helped a major copper mining operation reduce sealing water consumption by approximately 288,000 litres per day on a critical tailings handling asset.
The project involved retrofitting a mechanical seal to a Warman 550 underflow thickener slurry pump, replacing a traditional stuffing box packing arrangement that required frequent maintenance and significant operational intervention.
Underflow thickener pumps play an important role in mine tailings systems by transporting high-density slurry from thickeners into downstream tailings infrastructure. Reliability is particularly important in these applications because unplanned outages can directly affect production.
John Crane slurry pump retrofit reduces water consumption
The John Crane slurry pump retrofit was designed to fit the existing pump without requiring modifications to the asset.
The project included a mechanical seal package installed at the rear of the pump together with an adapter sleeve designed to suit the existing shaft arrangement.
According to John Crane, the seal flush system was designed to operate at approximately 11m³/h, although actual operating flow has been recorded at approximately 7.5–8m³/h.
A comparable pump using conventional packing was consuming around 20m³/h of water. Based on these operating conditions, the retrofit has reduced sealing water demand by approximately 12m³/h, equivalent to around 288m³ or 288,000 litres per day.
Mining operations seek improved tailings pump reliability
Before the retrofit, the pump relied on a traditional packing arrangement operating in highly abrasive service conditions.
This led to accelerated wear of the shaft sleeve, requiring replacement approximately every four months.
Each sleeve replacement involved extensive maintenance activity, including a full mechanical crew working across two shifts, use of a 100-tonne crane and extended equipment downtime.
The new sealing arrangement has been designed to align maintenance requirements with the site’s planned annual shutdown schedule, when impellers and liners are already replaced.
This approach aims to reduce the number of intrusive maintenance interventions required throughout the year.
Mechanical seal designed for demanding slurry applications
To support performance in abrasive mining environments, the sealing system incorporates a controlled seal-flush arrangement that maintains a clean fluid environment around the seal faces.
The seal also uses diamond-faced materials designed to provide additional durability if seal-flush pressure drops and solids enter the seal chamber.
John Crane said the installation represents the largest slurry seal sold by the company to date, with a shaft diameter of approximately 270mm.
Warren Smith, Global Mining Market Director at John Crane, said the project demonstrates how sealing technology can help reduce maintenance exposure while lowering water consumption and supporting planned maintenance strategies.
Read more industrial water and mining technology news in the Industrial and Water Management sections of H2O Global News.
FAQs
What is a tailings slurry pump?
A tailings slurry pump transports high-density mixtures of water and solids through mining processing and tailings management systems.
Why is sealing water used in slurry pumps?
Sealing water helps protect sealing components from abrasive slurry materials and supports reliable pump operation.
How much water did the retrofit save?
John Crane estimates the retrofit reduced sealing water demand by approximately 288,000 litres per day compared with a comparable packed pump operating under similar conditions.
