- To develop an alternative sanitising programme for mine service water. The alternative had to be equally or more effective in microbiological control. It also had to be environmentally acceptable, safe to work with and apply and address the challenge of volatile gas formation underground.
Environmentally Friendly Halogen Free Sanitation of Mine Service Water
The Brief
We helped the customer in these three ways:
We provided the mine with an alternative, more cost-effective disinfection programme. An alternative programme was required due to consistent price increases that were beyond our control.
We provided an alternative biocide programme that was halogen-free, hence was not associated with the formation of trihalomethanes, an environmentally persistent pollutant.
We provided an alternative that was not associated with the generation of volatile haloamines typically associated with traditional halogen-based disinfection programmes.
The Client
A deep level PGM mining project located on the Western Limb of the Bushveld Complex, with three Erikdsons Dams fed with mine service water.
The Work
Watercare Innovations recognised the opportunity to recommend an alternative disinfectant biocide. Not only was the alternative to be as (or more) effective in microbiological control, it also had to be environmentally acceptable, safe to apply, and needed to address the challenge of volatile gas formation underground. The ideal situation required the alternative to be more cost-effective than the historical BCDMH programme.
BO1450 was developed and recommended for testing. BO1450 is halogen (chlorine, bromine) free, and therefore is not associated with the formation of trihalomethanes. It is more environmentally acceptable than the BCDMH. It is a strong oxidising biocide that does not form volatile chloramines underground.
The raw materials are available domestically, and the product is manufactured locally. Pricing and logistics are therefore easier to manage and control, and being locally manufactured, BO1450 is significantly less sensitive to exchange rate fluctuations than the BCDMH, a direct import.
The Result
- Field trials proved BO1450 to be highly effective in killing the microbiological contamination of the dam. The product was, however, shown not to have the longevity required to maintain the Coliform Bacteria and E.coli at the specification of 0 CFU/ml for extended periods of time.
- Very low BCDMH residual in combination with BO1450 demonstrated excellent efficacy in controlling the microbial levels to the required specifications.
- The success of the trial resulted in the changeover from BCDMH to a combination biocide programme including BO1450 and significantly reduced BCDMH.
- The optimum dosage has been found to be 2.5 – 4.0 ppm BO1450, together with 0.1-0.2 ppm BCDMH (to maintain 0.05 ppm free halogen residual). The presence of stabilised halogen from the BCDMH is critical to the success of the microbiological programme
