Impala Platinum Holdings Limited (Implats) is in the business of mining, refining, and marketing of platinum group metals, as well as nickel, copper and cobalt. Impala is also the second largest producer of platinum in the world.
The Impala Platinum slag granulation cooling tower reservoir in Rustenburg, South Africa, had several flaws in the original sheet membrane system. These flaws allowed the extremely hot (80 C° [176 F°]) water to infiltrate the porous concrete, causing cracks over an area of approximately 4000m2, leading to severe water leakage.
Because of the nature of the slag granulation process, the reservoir could not be emptied for this repair process as not only would it stagnate their smelting process – but it would incur enormous labour and operational costs. For these reasons, repairs would have to be performed to the negative side of the concrete tower.
What are the risks involved with repairing cracks to the negative side rather than the positive? The process of repairing such serious water leaks from the negative side is a daunting task and in most cases impossible using standard waterproofing practices. Fortunately the Kryton Krystol waterproofing process was perfect for this situation.
Impala had numerous contractors come and perform trial test panels to the structure to find a solution which would work for this extremely large 6.5m deep (21.3 ft) reservoir structure. The only successful test panel performed was the panel using Kryton’s Krystol Crack Repair System, along with Krystol T1 & T2 Surface Applied System. Kryton’s South African distributor, Sanika Waterproofing Specialists, was thereby awarded the project in 2012, due to the observed excellent results of the Kryton products.
How they did it
Sanika had to remove the unsuccessful surface applied membranes and other products from the structure to prepare it for the repair and waterproofing process. How was it prepared? The entire structure was sandblasted to remove the obsolete and useless trial membranes and then pressure washed to ensure a clean and well prepared surface, exposing the raw concrete.
After preparing the bare concrete surface, the repair team had to act quickly with Krystol Plug as the almost boiling water poured through the cracks. The Krystol plug performed perfectly, stopping the water seepage through the cracks quickly allowing for continued Kryton Crack Treatment.
After the Krystol Plug successfully stopped the flow of water, the team employed a layer of dry-packed Krystol T1, followed by a layer of Krystol Bari-cote. A coat of Krystol T1 & T2 slurry was then applied, to completely waterproof the reservoir. The 10 man Sanika waterproofing specialist’s team successfully completed the entire project within 2 and half months in record time with no disruptions and exceptional results.
Impala was pleased with the work and had this to say, “Sanika performed the work in an exemplary fashion, with due respect to all safety, environmental and quality aspects. The work was executed within budget and on time with a very high standard of quality.”
Subsequent inspections where conducted a year later by G&H Consulting engineers an independent consulting engineer appointed by Impala. The engineers determined that the Kryton solution is long term and of superior quality.
“I have been in the waterproofing industry for more than 25 years, and prior to my introduction to the Kryton products I would never had tackled projects such as this as there were no products available to even remotely repair this reservoir from the negative side, especially while the reservoir was full with 6m deep and near boiling water”, says owner of Sanika, Paul Smit.
“The Kryton Kystol Plug, Krystol T1, Barricote and Kryton Krystol T2 made this normally impossible task not only possible but completely successful.”
All involved with this project namely, Senior Impala Platinum Engineers, the independent engineers from G&H Consulting Engineers and Sanika personnel were suitably impressed by the performance of the Kryton products.
This project was so successful that Anglo American Platinum Smelters (the Worlds number 1 Platinum mining company) in Polokwane, South Africa awarded Sanika Waterproofing Specialists, the Project of sealing their slag granulation cooling reservoir from the negative side in 2014. Another successful project using Kryton’s Krystol products.
