Material discovery won't scale DAC, but system redesign will!

[Ahmed Nasser]

The DAC industry has been fixated on finding the next best sorbent material, but they are completely missing the actual bottleneck. Scaling carbon removal isn't just an energy challenge; it is fundamentally a system design problem.

We have already reached the thermodynamic limit. CO2 dissolution in pure water is equivalent to the minimum possible energy needed to remove CO2 from the atmosphere (20 kJ/mol). What gets lost in current discussions is sorption rate and sorption capacity. Think of it like using a shovel to move dirt: sorption capacity is the size of the shovel, and the sorption rate is the speed at which you fill it. To scale, we must engineer our way around the thermodynamics of the problem.

Current fan-based systems are plagued with inefficiencies. They operate at low speeds and do not scale as fan-blade size increases. The ultimate solution lies in turbomachines. They are exceptionally efficient at processing massive volumes of air, backed by 70 years of rigorous engineering in aerospace and power generation.

Using turbomachines to compress air completely reframes the thermodynamic challenge. Operating at high pressure reduces the contacting area needed between air and the sorbent material. This, in turn, shrinks equipment size, land requirements, and ultimately the total facility footprint, which drastically reduces capital costs. Furthermore, high pressure increases the absorption rate and lowers residence time. This leads to much faster inventory turnover, maximizing the productivity of the working sorbent material. Together, these systemic improvements outline a process that is at least 3000x more efficient.

Compressing air is a challenging engineering task, but this is exactly where engineers, scientists, and investors should be spending their time and effort. This is how we scale carbon removal to gigaton capacity and drive costs below the $100/ton threshold.

If you need proof that this model works, look at the desalination industry. They transitioned from boiling seawater to using high pressure RO membranes. And ever since the number of desalination plants has grown exponentially. We are applying the same principles to carbon removal. Similar to how RO membranes concentrate water before rejecting salt, concentrating CO2 before removal is far more effective than running vast arrays of inefficient fans.

You can read more about this here: https://chemrxiv.org/doi/full/10.26434/chemrxiv.15002130

If you’re interested in contributing or collaborating on this work, please contact us at ViridasTe...@gmail.com

Happy to answer questions or dive into the technical details down below.