Advocates for hydrogen steel have made a new breakthrough in their long-term plan to wean the steel industry off of fossil fuel furnaces. Following the first public demonstration of a hydrogen-powered blast furnace, commercial steelmakers in Sweden have replaced liquid natural gas with hydrogen in their existing production setup. Despite the changeup, they experienced no change in outcomes.
While this demonstration is a big deal, it’s just one small step in the bigger question of steel production. The World Steel Association (WSA) says the overall energy efficiency of steel has improved 60 percent since the 1960s: “Sophisticated energy management systems ensure efficient use and recovery of energy throughout the steelmaking process for use within the steelworks boundary or exported from the site,” the organization explains.
But energy still “constitutes a significant portion” of production costs at up to 40 percent. And the overwhelming majority of steel plants still use coal as the primary fuel for blast furnaces. In fact, the natural gas technology used in Swedish steelmaker Ovako’s demonstration came about as an environmentally friendly alternative. The price of natural gas had continued to fall compared to coal in general, let alone the specific, lower-impurities form of coal used in blast furnaces.
In 2013, an American Iron and Steel Institute leader told Energy News the institute was eyeing natural gas over hydrogen. “[T]he institute had previously undertaken a long-term project developing technology to use hydrogen rather than coal to make molten iron; but now they are shifting their focus to replacing coal with natural gas,” Energy News reported.
Coal-powered blast furnaces are required to make pig iron the traditional way, but we may not need pig iron at all. “A process called ‘direct reduction’ uses natural gas rather than coke and blast furnaces to produce ‘Direct Reduced Iron (DRI),’ which can be substituted for pig iron,” Energy News explained.
And that’s just the smelting phase. To melt and machine steel for commercial use, steel mills like Ovako’s apply high heat again. And that heat has come from coal and, more recently, natural gas.
It’s into this existing infrastructure for natural gas that Ovako introduced hydrogen.
There are logistical snags in the good news. “More than 95 [percent] of the world’s hydrogen is today derived from natural gas and coal, causing nine to 12 tonnes of CO2 emissions for every tonne of H2 produced,” Recharge explains. The renewable forms of hydrogen, coded green and blue in the industry, are very costly and limited.
But having proof of concept of hydrogen steel processing could go a long way toward inducing more research, development, and subsidies of cleaner hydrogen in the future. The steel industry alone makes 9 percent of global fossil fuel emissions, according to the WSA. That means any chance to reduce is potentially huge, both financially and environmentally.
popularmechanics.com