Hydrova: Turning Dross into New Value

“Aluminum recycling is essential for sustainability,” says Andrew Stein, CEO of TST. “It saves over 95 per cent of the energy to recycle aluminium versus creating new primary aluminium. However, the process of melting aluminium scrap creates dross and salt cake that is difficult to recycle without having waste end up in a landfill. [Hydrova’s] technology solves that problem by utilizing 100 per cent of this co-product into valuable products.”

Julian Davis, Co-Founder and CEO of Hydrova

Without recycling, it would be virtually impossible for the industry to achieve sustainability targets. However, processes for recycling aluminium generate dross and salt cake waste streams, which have long been a headache for secondary aluminium producers. Hydrova sees a unique opportunity in these materials and has developed a process to valorise what have otherwise been deemed nuisance by-products.

Hydrova’s breakthrough technology transforms dross and salt cake into green hydrogen and sustainable, recycled aluminium, salt, and ingredients used in cement. This is achieved through a novel process which first recovers aluminium and then separates the remaining salt and oxide components. Hydrogen is produced during this process via a novel aluminium-water reaction technology, which utilizes unrecyclable aluminium left in the material after maximum aluminium recovery.

Hydrova is working with some of the largest aluminium producers in the world to repurpose waste using this novel approach. In a pilot project with TST, for example—California’s largest aluminium recycler, Hydrova has been able to demonstrate full resource recovery and hydrogen production from their black dross.

For over 75 years, TST has been sustainably recycling aluminium and producing high-quality alloys for industries around the globe including aerospace, automotive, appliances, lighting, building products and semiconductor. TST has long sought creative solutions for managing dross with limited success prior to partnering with Hydrova. California regulations have driven an increase in dross tolling fees, creating an acute problem for TST, especially with respect to black dross.

TST partnered with Hydrova to transform their black dross waste product into meaningful value streams. With Hydrova’s proprietary technology, TST is now demonstrating the production of 3 recyclable solid products along with green hydrogen. Aluminum and salt flux are recovered from the dross for direct reuse in the furnaces from which they came. Oxide products recovered from the dross provide a high-quality source of aluminium oxide, which is saleable to innovative cement producers—for example, CTS Cement, the inventors of Rapid Set cement, with whom Hydrova has built a partnership. Finally, the green hydrogen produced can be used as a clean fuel to help decarbonize TST’s furnaces via natural gas blending or electricity consumption via a fuel cell. In Hydrova and TST’s pilot, 100% of input material is recycled, leaving no material behind for landfill. This marks a major leap forward in bringing about a circular economy for otherwise landfilled waste.

“We are excited about our partnership with Hydrova,” says Andrew Stein, CEO of TST. “Their technology taps into new value from our dross while preventing waste generation. It is a win-win."

A circular and more sustainable approach

Millions of tons of dross and salt cake go to landfill every year. Hydrova’s mission is to keep this waste out of the landfill while helping customers tap into its unrealized potential. By focusing on high-quality, low-carbon products like hydrogen, aluminium alloys, and innovative cement products, Hydrova affords a second life to these waste streams in a way that is profitable to those that produce them.

To achieve net zero by 2050, aluminium producers will need new technologies that can help decarbonize their processes in innovative ways. Hydrogen will continue to be a critical clean fuel for any decarbonization strategy. At Hydrova, we believe that there is an exciting opportunity for decarbonization sitting right under our customers’ noses. Hydrova’s novel waste-to-hydrogen process creates a valuable decarbonization fuel, helps reduce tolling fees by recycling waste into valuable products, and improves profitability by generating these value streams, creating a win-win-win solution for climate change, waste reduction, and aluminium recyclers.