2020
Durban

Due largely to water wastage, increasing demand and drought, South Africa has been under major
water constraints for many years. As such, there exists a need to stabilise the system with emphasis being placed on the re-use of water. The eThekwini Municipality believes that a remix water system, together with many other strategies, could resolve their issue by providing for the deficit in supply. One
of the strategies employed to resolve the water shortage, was to create a first-of-its-kind remix plant in the Bluff, Durban.

Stefanutti Stocks Coastal undertook the civil construction of a remix demonstration plant at eThekwini’s central wastewater treatment works. The civils included a 6.25Ml/d advanced water treatment demonstration facility, that will utilise Hitachi’s Remix system. This process combines direct potable re-use water with desalinated seawater, with the aim of accomplishing a 30% energy saving compared to existing desalination systems. The purpose of this pilot facility is to establish the effectiveness, reliability and if any, the advantages of the remix technology. This will empower crucial decision making by the stakeholders, and more so, allow the municipality to consider the feasibility of large-scale commercial implementation.

The project scope comprised all of the civil and marine works: the installation, testing and commissioning of all mechanical and electrical equipment (free issue from Hitachi); the procurement, manufacturing, installation, testing and commissioning of pipework, valves, cables and other ancillary mechanical and electrical infrastructure. This was a huge task and also required the use of a 1.4 km seawater pipeline.

Given their longevity and reliability, a wide range of Sika products were used for this project. The bund area walls and floors were primed using the Sikafloor®- 161 primer. Sikafloor® 161 extend -T was used as a scratch coat to fill blow holes and imperfections; and a 3-layer system of Sikagard®- 63 N was applied as a chemical protective coating. 

The main factory floor, and storage rooms floors, were treated with Sikafloor®- 161 Primer and the Sikafloor®- 263 SL self-levelling flooring system at 1mm thick. All the floor joints were primed with Sika® Primer-3N and sealed using the Sikaflex® PRO-3 i-cure.

The separation tanks were treated with Sikalastic®- 152 as a waterproofing and protection system. It was a product designed for waterproofing hydraulic structures like water storage tanks, concrete pipes, bridge parapets, water  canals etc.

The main holding tank was primed using the Sikafloor®- 161 primer. A scratch coat of Sikafloor®- 161 and Extender-T was used to fill the blow holes and imperfections on the surface; as well as the application of a 3-coat system of Sikagard®-63 N chemical resistant coating.  

This project needed results that would both impress and stand the test of time. Many specialised products had to prove that their use contributed to the aim of the project process: the re-use of water. It was apparent that the Sika products were indeed the key ingredients on a project of this magnitude...and yes, a pinch of salt too.  

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