South African water and wastewater specialist Talbot has secured the rights to market Vibrating Sheer Enhanced Process (VSEP) technology, an efficient and cost-effective solution for mining and mineral resource companies looking to treat highly contaminated and difficult wastewater streams.

The technology is provided by US company New Logic Research Inc and uses a patented membrane vibration system that is able to tolerate waters that aren’t typically treatable by conventional ultrafiltration and reverse osmosis (RO) systems.

When the final option may be the first choice

“Ironically, VSEP is often the last option for companies that have tried conventional methods and found that their waste streams are just too dirty,” says Talbot Consulting Services general manager Claire Lipsett.

The technology provides a far more efficient solution at a reduced cost and produces water of exceptionally high quality – SANS 241 drinking quality if so required.

“Miners and precious metals refineries facing the prospect of operating or investing in large, high-capex multi-stage wastewater treatment systems now have a far more cost-effective solution with VSEP, which can achieve in one stage what traditional solutions would typically accomplish in five or six,” she says.

A compelling comparison

Apart from the technology’s energy, chemical and operational cost benefits, companies can save through the recovery of significantly larger volumes of high-quality water that can be used as a substitute for municipal supply. Importantly, there is also a marked reduction in the volumes of final concentrate and related storage and/or disposal costs and their environmental impacts.

Traditional RO treatment methods typically result in a substantial brine stream, anything from 25% to 50% in highly contaminated applications. VSEP can concentrate brine streams to a final volume of less than 10%, representing an overall system recovery of more than 90%.

Valuable product recovery

“In addition, operations can utilise VSEP to recover ultra-fine particles of product from their waste streams that they can then return to the process. A number of South African case studies reveal that through VSEP’s ability to salvage valuable product, payback time can be reduced from more than six years to under 12 months while at the same time achieving accompanying water-saving benefits and environmental compliance,” says Lipsett.

Helping miners achieve regulatory compliance

She adds that VSEP holds enormous potential in the mining industry to assist with the recovery and discharge of process streams, and the production of potable water for communities in remote locations. Mines are under increasing pressure to manage their water impacts, both in respect of abstraction in severely water-stressed regions and impact on groundwater qualities.

“The Department of Human Settlements, Water and Sanitation recently announced plans to implement drastic measures to ensure that certain sectors of the economy, and mining, in particular, take responsibility for the water impacts arising from their operations.

“We see VSEP and this renewed focus on compliance as a niche market opportunity, and an opening for us to put our in-depth experience in water treatment to use,” says Talbot CEO Carl Haycock.

Mobile pilot plants and water modelling

Talbot is unique in the fact that it offers mobile laboratory and pilot trial options to potential clients while developing in-house models to demonstrate the potential of utilising VSEP within a given operation.

These have been employed at a mine on the Mpumalanga coalfields where future expansion is hampered due to its brine storage facility nearing capacity. The implementation of VSEP would not only reduce daily brine production levels by up to 50%, allowing for a substantial increase in mine activities, but produce large volumes of high-quality water for potential supply back to the mine or to local communities.

Talbot’s mobile plant remains on site for a minimum of two weeks with regular samples being analysed at the company’s fully-accredited in-house laboratory. The information gleaned serves as the basis for a full plant design and the preparation of business cases looking five and 10 years into the future.  

Pilot studies provide significant confidence to plant performance assumptions and financial projections. Talbot has developed purpose-built financial models which allow for the assessment of the life-cycle cost and long-term viability of each project.

“We work with clients to make their projects cashflow positive – where savings and product recovery pay for the plant itself. We are seeing a big drive from financial institutions to support ‘green initiatives’; we access this money and provide the opportunity for clients to rent or lease equipment in cases where cashflow constraints restrict their ability to buy the project outright.” says Talbot economist Mike Smith.

VSEP is fouling resistant owing to its unique vibrating membrane. Modular units can treat between 25kl and 100kl a day, with multi-unit applications available for larger flow rates.