Suvo transforms nickel slag into low-carbon cement

Suvo Strategic Minerals has turned nickel slag, a highly-polluting waste product of nickel pig iron production, into a high-strength, low-cost and low-carbon cement.

Confirming positive laboratory testing that could revolutionise the centuries-old cement industry, the company says its recent trials in conjunction with Makassar State University (UNM) in Indonesia achieved a compressive strength of 37.5 megapascals (MPa) after just seven days.

The slag, which is commonly stockpiled or committed to landfill, was provided by PT Huadi Nickel-Alloy Indonesia (PT HNI) from its nickel pig iron operation in South Sulawesi.

The news comes just 12 months after Suvo first signed a licencing deal with Murdoch University in Western Australia to use its proprietary technology for turning fly ash – a waste product of coal-fired power stations – into a low-carbon cement for the manufacture of geopolymer concretes.

Since then, management has conducted further tests, determining that the best waste products for the process are those highest in alumina silicate, including the nickel slag.

The company is working to produce a viable and more carbon-friendly alternative to the traditional Ordinary Portland Cement (OPC) – the world’s most common form of the product.

We are excited to have commenced this workstream in Indonesia testing the byproduct of one of the Country’s largest miners, with our ultimate goal being to manufacture an environmentally-friendly and low-carbon alternative to Portland cement. Achieving up to 37.5Mpa after only 7 days is an outstanding first round trial result for the Company and could provide an entry into a large industry.

Banks says the company will now kick off its next round of testing with UNM and will provide the results of both trials to PT HNI in a bid to advance negotiations with a view to forming a partnership for the ongoing offtake of the nickel slag and the commercialisation of a low-carbon cement.

Once treated, geopolymer concrete – while not a new invention – acts in a similar way to OPC from a performance standpoint and can be manufactured at a similar, of even lower, cost. But the key and biggest risk to commercialising the process, according to Banks, is finding a sufficient supply of waste product.

In pursuing the green cement strategy, Suvo has recognised the immediate problem for OPC, with its production responsible for almost 8 per cent of human-induced global greenhouse gases presenting a significant environmental challenge.

Not only is the global demand for OPC vast – representing the equivalent to building New York City every 40 days – its manufacture is highly carbon-emitting. Indeed, if the world’s cement producers were classified as a single country it would run third behind only the United States and China in the quantity of carbon produced.

Cement manufacturers are actively looking at multiple ways to reduce their carbon footprint and Suvo’s innovative approach to producing a geopolymer concrete using nickel slag to help tackle that carbon challenge plays directly into that narrative. By using the waste material as feedstock, the process eliminates the carbon footprint associated with traditional raw materials, as the emissions have already been accounted for during primary production of the metal.

In seeking partners to trial the process, Suvo recently cut its deal with PT HNI, one of Indonesia’s biggest nickel producers. As well as testing the company’s nickel slag for suitability, the cooperation agreement also includes exploring for potential commercial applications and an ongoing supply of the waste product.

OPC has been around for 200 years and was first invented and patented by Joseph Aspdin from Leeds in 1824. It has undoubtedly served the test of time and has been instrumental in industrial progress across that period.

But if the entire process of heating powdered limestone mixed with clay in a furnace and grinding the resulting clinker to a powder sounds decidedly Dickensian by today’s standards, then it probably is.

Suvo has taken a bold step to try and revolutionise a vast market. Get it right and even a tiny slice of a US$14 trillion (AU$20.8 trillion) global construction market will be nothing to sniff at.

Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au