Gold mine installs oily-water treatment, recycling system

22nd March 2013 By: Sashnee Moodley - Senior Deputy Editor Polity and Multimedia

Environmental solutions company Procon Environmental Technologies reports that, in January, it supplied an oily-water treatment solution, Ultraspin, for a car wash bay at gold producer Gold Fields’ Tarkwa mine, in Ghana.

Procon MD Andrew Miller says that the company will commission the system in March.

“We were approached by the miner’s contracting company to provide the oily-water separator and water recycler for a packaged plant, where industrial filtration company Filvent is providing a civil design and high-pressure wash system,” he says.

Miller notes that lately there has been a drive among mining companies to recycle and remove oil from water.

“The environmental benefits of the system are twofold, as it removes hydrocarbons from the water and allows up to 80% of the treated water to be recycled,” he adds.

The Ultraspin system entails two phases – the spill-recovery system and the oily-water treatment system.

The spill-recovery system uses an automated floating stainless steel skimmer, with debris strainer and pump, which removes oil spillages into the first pit of the wash bay.

The ES15 Ultraspin model then treats 15 m3 of water an hour to remove any residual oil in the water and enhance its quality.

Oily water is pumped through a cone-shaped separator, creating a spinning vortex that, in turn, creates a separation force.

The vortex accelerates as it moves down the cone and strong centrifugal forces push the heavy water phase to the outside of the vortex, while the lighter oil phase moves to the centre.

The separated oil is then removed through an orifice that is located at the inlet end, while the treated water is discharged through the opposite end.

“The centrifugal force generated inside the vortex of the Ultraspin oil separator is about 1 000 times the force of gravity. As a result, an effective oily-water treatment can be achieved, even with emulsified oil droplets,” Miller states.

The water can then be recycled for further cleaning of mining vehicles at the wash bay.

The system is cost effective and does not use any chemicals, as it works on a simple vortex principle. Miller explains that the system’s oily-water separator can work on all types of oil pollution.

Following the commissioning of the system, Procon will provide mine site operators with training on the Ultraspin system, which consists of component identification, system functioning, troubleshooting and maintenance.