The iron and steel industries are among the most persistent and massive polluters in the global economy, accounting for a staggering share of worldwide greenhouse gas emissions. Over the past decade, a wave of climate tech startups has emerged with the ambition of cutting these emissions, primarily by attempting to invent entirely new methods for manufacturing the metals from scratch. However, a San Francisco-based startup called Helix Carbon is convinced that the broader clean-tech ecosystem has been going about the problem entirely the wrong way.
"Any attempt to decarbonize the steel industry without dealing with the blast furnace is not going to work," David Brown, Helix Carbon’s co-founder and chief executive officer, told TechCrunch. A blast furnace is the colossal, industrial-scale infrastructure responsible for transforming raw iron ore into the metallic iron that eventually becomes steel. Rather than trying to completely replace or bypass blast furnaces with unproven, expensive alternatives that could take generations to scale, Helix wants to clean them up from the inside out. Its engineering approach promises to radically slash the steel industry’s carbon footprint while simultaneously boosting profit margins for iron producers—a rare win-win scenario for a notoriously dirty, carbon-heavy industrial process.
For centuries, blast furnaces have forged iron using coke, a heavily processed, carbon-rich form of coal. This material is fed into the furnace to help convert raw iron ore, which is fundamentally iron bound tightly up with oxygen, into pure metallic iron. The burning coke supplies the immense heat required for the chemical reaction, but it does not actually take part in the reduction process directly. Instead, carbon monoxide gas produced from the combustion of the coal does the heavy lifting, actively reducing the iron by stripping away its oxygen atoms.
Naturally, this chemical process releases monumental amounts of carbon dioxide, or CO2, which is typically vented straight out of the stacks and dumped directly into the atmosphere. But Helix Carbon has devised a clever technological workaround to turn that exact waste carbon dioxide into usable carbon monoxide, recycling it right back into the blast furnace to close the loop.
The core of Helix Carbon’s process relies on an advanced electrolyzer, a specialized piece of hardware that utilizes electricity and a chemical catalyst to break off a troublesome oxygen atom from a carbon dioxide molecule. While electrolyzers themselves are far from a brand-new invention, Brown noted that his startup’s proprietary design possesses a critical differentiator: it can handle the entire, raw exhaust stream directly from a blast furnace. Most commercial electrolyzers available today are far too delicate to deal with raw, untreated industrial exhaust. They typically require heavily purified, highly concentrated carbon dioxide to function properly, meaning that standard exhaust usually has to undergo expensive, energy-intensive preprocessing before they can even touch it. Helix’s system bypasses that limitation entirely.
By injecting freshly generated carbon monoxide directly into a blast furnace, iron and steel producers can significantly reduce the amount of coke they need to burn. However, the precise extent of those reductions remains a subject of ongoing debate within the scientific and industrial communities, according to Brown. Some academic papers and scientific studies suggest that as much as 90% of the traditional coke could theoretically be eliminated from the equation, while other more conservative studies estimate the feasible reduction is closer to 30% to 40%.
To establish a realistic foothold in the market, Helix Carbon is proposing that industrial iron producers start by replacing a modest 33% of their traditional coke consumption. The company calculates that using its technology to achieve this single milestone would save producers roughly $14 for every single ton of iron produced. "That may not seem like a lot, but margins in the iron industry are famously thin," Brown explained, emphasizing how even minor operational savings can fundamentally alter the financial viability of a plant.
The global iron and steel industries represent a massive, combined $2 trillion market, according to market data compiled by Grand View Research. This sheer financial scale makes the sector an immensely appealing target for young, ambitious startups looking to make a massive impact on global carbon emissions. Yet, it is also a notoriously slow-moving industry, constrained in large part by the extraordinary lifespan of its capital equipment. "There are blast furnaces that have lived for over 100 years," Brown noted, highlighting why trying to replace them entirely with brand-new infrastructure is an uphill battle.
To generate revenue earlier in its lifecycle and avoid waiting decades for traditional steel mills to overhaul their core assets, Helix Carbon has formulated a secondary go-to-market strategy that targets the specialty chemicals industry first. "We don’t need to capture the CO2 first," Brown said. "We just utilize it, and that opens up the door of making chemicals on-site right out of waste streams." By selling directly to chemical producers who can immediately put the captured and converted gases to work, Helix can commercialize its technology much faster.
The startup’s broader vision and technical strategy were put on full display when Helix Carbon presented live onstage during the Startup Battlefield pitch competition at TechCrunch Disrupt in San Francisco. The high-profile event brings together some of the world’s most promising early-stage companies to pitch a panel of expert judges and industry leaders, showcasing technologies that have the potential to disrupt major global markets.
As the iron and steel sectors face mounting regulatory pressures and societal demands to curb their greenhouse gas emissions, approaches that work within the constraints of existing heavy industry—rather than demanding its immediate replacement—may ultimately prove to be the most viable path forward. By focusing on the humble blast furnace and turning its greatest waste product into a valuable resource, Helix Carbon is betting that practical chemistry and smart engineering can solve one of heavy industry’s oldest and dirtiest problems.
