Why SA needs to invest in zinc
26 August 2020 | Web Article Number: ME202020292
SOUTH Africa needs to invest in zinc if its infrastructure drive is to be viable, writes Simon Norton, International Zinc Association Africa Desk.
Last month the Presidency named the first projects in its R2.3-trillion infrastructure drive aimed at resurrecting the economy over the next decade. The list includes projects ranging from key water supply and irrigation developments to energy, roads, housing, and fish-farming plans.
But if Eskom has taught us anything, it’s that investing in infrastructure is one thing -- maintaining it is another. While the government’s approach is certainly positive, we need to caution against money being wasted because projects aren’t designed to last, or easily succumb to premature corrosion particularly at the coast where conditions can be severe.
What’s required is a strategy that prioritises long-term gains over short-term profiteering. Focusing on quality and performance today will ensure long-term benefits, and ultimately cost savings.
One way to ensure the longevity and resilience of projects in the construction industry and civil engineering sector is to pay careful attention to how new build projects are specified and specifically selecting materials. This is where hot dip galvanizing has a key role to play as one of the most cost-effective ways to both prevent the premature corrosion of steel and to ensure a long-term, low-maintenance service life of the project.
Hot dip galvanizing, simply the process of coating steel with zinc in order to protect the material from corrosion, has the potential to protect steel structures from corrosion for up to 50 years in the right environment. The appeal of hot dip galvanizing is that it is only marginally more costly than painting at the outset of a project, but the savings in terms of long-term maintenance-free service are exponential.
Galvanized steel is completely recyclable too. This offers both an environmental and economic benefit, and in a pressurized economy such as in South Africa, it is hard to argue against a solution that can guarantee long-term savings.
Importantly, the zinc that is needed for hot dip galvanizing is widely and abundantly available around the world. In fact, the US Geological Survey estimates the world’s total zinc reserves at 225 million tons, which is more than significant.
The new Orion zinc mine in Prieska in the Northern Cape will, on average, produce 59,130 tons a year of zinc in concentrate compared to SA’s output of 115,000 tons in 2019, according to Minerals Council SA data. However, it is to be noted that South Africa has no zinc refinery of its own and must import refined zinc ingots.
In the context of climate change and the goals outlined in the UN’s Sustainable Development Goals for the reduction of greenhouse gases, it is crucial that all developments take environmental impact into account.
Zinc is not only a cost-effective material, thanks to its natural abundance, but it is also sustainable as it can be recycled without losing or compromising any of its metallurgical properties or overall value. As such, it can be used over and over again with its recycling capability ensuring the reduction of concentrate demand, energy use, emissions and waste disposal.
Zinc also has a reclamation rate of 80%, according to the American Galvanizers Association, while some 30% of zinc currently in use is from reclaimed zinc sources.
President Cyril Ramaphosa has said that infrastructure development is central to the country’s economic response to the coronavirus pandemic, with Minister of Public Works and Infrastructure, Patricia de Lille, adding that infrastructure-led economic development could be an effective way to stimulate economic growth. What needs to be added to this is an approach that prioritizes long-term sustainability over the short-terms gains for a select few.
In order to achieve the growth we so desperately need to provide millions of South Africans with job opportunities, we need to take a future focused approach that includes ensuring the resilience of our infrastructure. What better way than to design and build new infrastructure using galvanized steel and maximising the capacity of South African hot dip galvanizers of whom there are 28 spread across SA?