KEEPING IT CLEAN The SlurrySucker dredging equipment could quickly dredge the sewage pond before there was any danger of overflow
A recent two-week trial at a mine on South Africa’s West Coast has reaffirmed the value of specialist pumps supplier Integrated Pump Rental’s (IPR’s) SlurrySucker dredging unit – even in saltwater and high-volume conditions.
The mine’s main process water pond offered a significant challenge, as it filled with sediment and highly corrosive seawater within a week. Moreover, the mine was looking for a safer and more cost-effective option than its existing solution, which entailed divers, equipped with manually operated suction pipes, to remove sediment.
“This large pond – about 80 m by 80 m and 7 m deep – is central to the mine operation, as it feeds all the process plants. It is, therefore, vital that sediment is removed continuously, quickly and in large quantities,” notes IPR rental development manager Ruaan Venter.
During the trial, the SlurrySucker pumped 250 m3/h of sediment with a solids content of 30% to 40%. This allowed for the removal of between 60 t and 70 t of sediment from the pond every hour using specialised dredging equipment.
“When in contact with conventional metal pump components, saltwater is extremely corrosive and, over time, can cause a lot of damage to the equipment, leading to the frequent replacement of wear plates and impellers. In addition, the integrity of the framework will also be compromised,” says Venter.
He adds that, to mitigate corrosion, IPR provides customers with a full stainless steel pump solution with rubber-lined pipes to transport material from the pond.
IPR says the success of the trial has raised interest from other mining operations along the coastline.
“Demanding conditions like these would warrant the customer’s considering a purchase option. It is likely that the SlurrySucker would be operational every day on these ponds, making this specialised equipment a valuable investment in the efficient running of the plant,” Venter adds.
Meanwhile, IPR’s growing reputation for prompt and cost-effective dredging in the mining sector has resulted in the pumps supplier also tackling sewage settlement ponds.
A recent contract at a wastewater treatment plant is part of a “strong flow of repeat business” from South Africa’s platinum mines, says Venter.
The plant is operated by the mine, but also services the local municipality and nearby communities.
“Using our SlurrySucker dredging equipment, we could quickly dredge the sewage pond before there was any danger of overflow,” says Venter.
“Regular monitoring and dredging of these facilities allows the mine to effectively settle the sewage flowing in and keep the system operating well.”
He adds that the SlurrySucker uses a pump with an open-vane, non-clogging impeller – an important innovation in these applications, as there are still solid objects and sanitary products that could block a normal pump.
“The design of our system, and the way it channels water flow to agitate the settled material, ensures that there is no chance of damaging the pond liner. This is also vital in protecting the environment from any leakage or contamination.”
A consequence of population growth is that wastewater treatment plants are often under increasing load, leading to sewage ponds filling with sludge more quickly. These ponds would usually need to be dredged about once a year, says Venter.
For conditions that demand more frequent dredging, Venter cites the option to buy, rather than rent, SlurrySucker units. Moreover, training is provided by IPR to upskill local workers in the correct operation of the equipment.