Grantee Research Project Results
Final Report: Complete Resource Recovery and Hydrogen Production from Secondary Aluminum Processing Waste Processing Waste
EPA Contract Number: 68HERC23C0027Title: Complete Resource Recovery and Hydrogen Production from Secondary Aluminum Processing Waste Processing Waste
Investigators: Reifschneider, Rostam
Small Business: Hydrova Inc.
EPA Contact: Richards, April
Phase: I
Project Period: December 12, 2022 through June 11, 2023
Project Amount: $100,000
RFA: Small Business Innovation Research (SBIR) Phase I (2023) RFA Text | Recipients Lists
Research Category: SBIR - Homeland Security , SBIR - Sustainability , SBIR - Air and Climate , SBIR - Water
Description:
A novel hydrometallurgical recovery process has been developed, enabling complete resource recovery and hydrogen production from otherwise landfilled aluminum production waste.
Aluminum recycling is critical to the sustainable production of aluminum, but this recycling process is not air-tight in that it creates inevitable waste byproducts called dross and salt cake. The secondary aluminum processing (SAP) industry in the US sends over 1 million tons of dross and salt cake waste to landfill every year, costing the industry billions of dollars. Sending this waste to landfill additionally causes leachate, gas evolution, and explosion hazards, which can all have a detrimental impact on both the environment and human health. Most crucially, when industrial waste such as dross and salt cake contains valuable materials that could have been reused in industry yet is landfilled, this necessitates extracting finite resources from the earth. These reasons, among others, are why major aluminum-consuming companies such as Apple, Subaru, and Anheuser Busch are working towards achieving zero waste as part of a broader movement towards the circular economy.
By repurposing the materials within dross and salt cake, Hydrova can drastically decrease energy use and emissions as well. It is 94% less carbon-intensive to recycle aluminum than it is to produce virgin aluminum from bauxite. By recovering aluminum from dross and salt cake, emissions can be reduced by 14.25 tons of CO2 per ton of aluminum recycled.
The research in this SBIR Phase I proposal aims to accomplish previously unattainable levels of materials separation and hydrogen generation to pioneer domestic dross and salt cake recycling. Current dross and salt cake recycling technologies are insufficient for cost-effective recycling of SAP waste in the US, evidenced by over 95% of this material (over 1 million tons annually) going to landfill. Meanwhile, landfilling dross and salt cake is an unsustainable option that creates a billion-dollar waste challenge for SAPs.
In this SBIR project, Hydrova has successfully demonstrated a zero-waste recovery process for recycling dross while producing green hydrogen. This process has the potential to reduce the amount of dross and salt cake in the US currently landfilled every year from over one million tons down to zero, achieving a full closed loop in the US aluminum recycling system. This specifically helps achieve the EPA's National Recycling Strategy including Objective A1 for promoting market development of recycled commodities and Objective A3 for increasing manufacturing use of recycled material feedstocks in domestic markets.
Summary/Accomplishments (Outputs/Outcomes):
During Phase I, Hydrova successfully demonstrated full resource recovery from dross while achieving the established technical objectives. The technical objectives included a 10x improvement in Cl- content reduction from NMP as well as enhanced hydrogen production and purity from dross and salt cake compared to incumbent technology. The ultra-effective chloride content removal demonstrated under Phase I enables NMP recovered from aluminum dross waste byproducts to be resold into high-performance cement applications. Hydrova has established a partnership with CTS Cement, the producers of Rapid Set® Cement, and produced the first calcium sulfoaluminate cement products during this Phase I grant. Pure hydrogen produced provides a clean fuel source for aluminum producers to use on-site for a number of different decarbonization applications including direct combustion, blending with natural gas, and fuel cell power. In parallel with the project, Hydrova completed a successful pilot trial with California's largest aluminum producer, TST Inc, producing aluminum ingots, fluxing salt, hydrogen gas, and Rapid Set® Cement from aluminum dross. Additionally, Hydrova performed full-scale tests with equipment suppliers to further de-risk commercial implementation of the technology.
During Phase II, Hydrova is partnering with a major US SAP to further derisk scale up of this technology and establish the first full-scale commercial system to process the majority of the aluminum producer's waste. This system will enable Hydrova's process to begin enacting large-scale environmental impact via the waste recycled and green hydrogen produced.
Conclusions:
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, aluminum 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. This helps reduce waste tolling fees and creates a win-win-win solution for climate change, waste reduction, and aluminum recyclers bottom line.
During Phase I, Hydrova's work was featured on national tv (CBS Mornings), in CNBC, on the cover of Scrap Recycling magazine, and in various industry publications including Recycling Today, Light Metal Age, AlCircle, and Aluminium International Today, all of which highlighted the impact of the EPA SBIR support.
SBIR Phase II:
Complete Resource Recovery and Hydrogen Production from Secondary Aluminum Processing WasteThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.