Frontier facilitates second round of carbon removal purchases

Biomass Carbon Removal and Storage (BiCRS) is a process that removes CO₂ from the air through biomass and stores it. Arbor is developing a scalable and low-cost approach to BiCRS based on modern rocket engine technology. The team brings together deep experience in turbomachinery, combustion, and manufacturing. Their modular systems combine compact gasification with a supercritical CO₂ turbine, offering feedstock flexibility, high electrical efficiency, and permanent geologic storage.

Mine waste, or “mine tailings," has the potential to trap CO₂ when exposed to air and water. Arca is accelerating this process by using autonomous rovers to stir the tailings and increase the speed of CO₂ weathering reactions with the alkaline material. This approach eliminates the costs usually associated with moving tailings to a processing site by enabling the reaction to happen on-site. The team is also developing a pre-treatment technology to further increase the CO₂ reaction rates and reduce costs.

Oceans store a quarter of the CO₂ emissions generated by human activity. Captura is developing a sea-based electrodialysis machine that generates a sequesterable stream of atmospheric CO₂ directly from ocean water. Captura’s direct ocean capture approach has the potential to reduce removal costs by eliminating the need for air contactors and sorbent/solvent and utilizing existing infrastructure such as desalination plants and oil and gas platforms.

Carbon To Stone is developing a new approach that couples Direct Air Capture (DAC) with mineralization. Conventional DAC processes use heat or pressure changes to regenerate solvents reacting with CO₂, resulting in high energy use. Carbon To Stone chemically regenerates the solvent by reacting it with alkaline material such as steel slag, fly ash, or mine tailings to produce carbonates that could be used for alternative cements. This approach reduces both the energy and the cost required for the same tonnage of CO₂ captured.

Cella is accelerating the process of converting CO₂ into a mineral by injecting it into volcanic rock formations together with saline water and geothermal brine waste. Typical in-situ mineralization approaches are water intensive, but Cella’s design recycles 100% of the injected water. Their approach has the added benefits of integrating low-carbon geothermal heat, which reduces the cost of DAC, and disposing of geothermal brine which is usually a waste product.

CREW is developing a container-based solution to enhanced weathering, making it quicker and cheaper to deploy. In this first project, they will co-locate with a wastewater treatment facility to remove carbon resulting from the incineration of organic waste, but the system can flexibly capture CO₂ from a variety of sources. The system consists of weathering reactors that increase the speed of reaction of CO₂, water, and carbonate or silicate feedstock. CREW’s ability to measure and quantify system effluent will serve as a model that researchers can use to better understand weathering reactions and ensure that the discharge doesn’t affect local ocean ecosystems. Ultimately, storage of CO₂ as bicarbonate ions in the ocean is a secure and scalable storage method.

Inplanet uses enhanced weathering (EW) to permanently sequester CO₂ and regenerate tropical soils. While most EW studies to date have been conducted in Europe and North America, Inplanet will be deploying this technology in Brazil, where warmer and wetter conditions could result in faster rock weathering rates and thus faster CO₂ drawdown. Inplanet will be teaming with local mines and quarries to source rocks, and with the University of São Paulo to develop monitoring, reporting, and verification (MRV) field stations to collect better data on how weathering changes with different silicate rocks under a variety of weather and soil conditions across Brazil.

Kodama Systems, in partnership with the Yale Carbon Containment Lab, is running a pilot in the Nevada desert to bury woody biomass thinned from forests at risk of wildfires. Biomass burial has the potential to be a low cost and highly efficient form of CDR (defined by how much carbon in the biomass gets stored), but there are open research questions regarding durability, such as the rate of decomposition. Kodama is using a novel approach to construct underground “vaults” that minimize water, oxygen, and microbial activity that could decompose the biomass, while employing numerous surface sensors to detect any decomposition. By determining optimal vault designs, they will be able to minimize CDR costs and maximize storage durability.

Nitricity is integrating carbon removal into an innovative process for the production of clean fertilizer. Traditionally, the production of nitrophosphates for the agricultural industry is an energy- and emission-intensive process. The Nitricity team is pioneering a carbon-free process to make nitric acid, and is testing the use of atmospheric CO₂ for a subsequent carbonation reaction that yields nitrophosphates while permanently storing the carbon in the form of limestone.