Whether acidic, hard or containing high levels of suspended solids, there is a filtration solution out there for different types of mine water. Henk Smit, managing director of Vovani Water Products, discusses a few of popular options.
What are some of the biggest challenges in mine water treatment?
One of the major challenges is still the quality of the water to be treated, as water quality varies from mine to mine and each presents a unique challenge. One problem is Acid Mine Drainage (AMD), where highly acidic water has leached and retained poisonous heavy metals from inside mines. Past treatment interventions concentrated mainly on neutralising low pH levels and removing heavy metals, but this still leaves an elevated concentration of salts in the water.
Another challenge is that of educating all role players on the newest treatment technologies available. These role players need to be involved at the outset, so that the best, most effective and affordable treatment solutions are implemented right at the start. This benefits not only the mine itself but also the communities who live nearby.
How do your products and services solve these challenges?
As Vovani Water Products represents many international products used in water treatment, we are in a unique position to work with mines, consulting engineering firms and original equipment manufacturers, to supply our various product offerings in the form a unique packaged solution which is right for any given mine.
Further, Vovani is a channel partner of international giant GE Water Technologies, allowing us to offer the latest technologies from ultrafiltration (UF) membranes to reverse osmosis (RO) membranes. Additionally, with our other suppliers, ROPV, FEDCO, PASS and AQUA SOLUTIONS, we can assist our clients with the best solution, whatever their water treatment challenge.
Could you discuss a case study where your products were chosen to improve water quality at a mine?
In Namibia our Zeeweed 700B Sevenbore Inside-Out UF membranes were chosen at The Langer Heinrich Uranium Mine close to Swakopmund, to treat the wastewater as pre-filtration prior to it reaching the nano-filtration (NF) membranes.
“In Namibia our Zeeweed 700B Sevenbore Inside-Out UF membranes were chosen at The Langer Heinrich Uranium Mine close to Swakopmund”
These UF membranes remove the high solids loading in the wastewater, so that the feed water going to the NF spiral-wound membranes is of a higher quality. As a result, these membranes will have to deal only with the removal of certain dissolved minerals – as the processes on the mine require.
The strength of the Sevenbore ZW700B UF membranes made them perfect for this application as they are 10 times stronger than single bore fibres and more robust. This is ideal for handling the tough conditions of the feed water at the mine.
What other sectors benefit from your offering?
Vovani also serves the industrial, agricultural, hospital and medical environments, and municipal and other government sectors. We also work together with non-profit organisations, and have specially tailored offerings for that particular market.
What technology do you foresee becoming more widely used across the different sectors you serve and why?
UF is becoming a more widely used treatment technology, as pre-filtration to RO and as a treatment process on its own. UF is able to treat surface water to the highest quality potable water standards for any type of human settlement, from small communities to the largest cities.
Many applications do not require RO treated water yet they do require the removal of high suspended solids, bacteria and viruses, so that the treated water is safe for human and animal consumption. The same high quality water is required in numerous agricultural applications. UF is the ideal technology for these applications, especially the Zeeweed 700B UF modules from GE Water, available locally from Vovani Water Products.
UF is also becoming a more cost effective solution as a pre-treatment step prior to RO desalination. Pre-treatment has both short- and long-term advantages. They prolong the life of membranes, lower operational costs and maintenance downtime, and enhance plant efficiency.
Further, at cities next to the coastline (where South Africa is currently experiencing some the worst water shortages) installing seawater desalination plants can provide long-term water security. UF plays an important role as part of this particular treatment process, ensuring plants function more effectively and economically.