openair-collective / openair-epiphyte

Epiphyte is a miniature, stand-alone, open source direct air capture machine that removes CO2 from the air, designed by OpenAir volunteers.
CERN Open Hardware Licence Version 2 - Permissive
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ENGR: Improve/reduce resistance of airflow through sorbent panel #15

Open KCollins opened 5 months ago

KCollins commented 5 months ago

Related to Issue #14 .

With our current sorbent panel, the sorbent is tightly packed in to maximize quantity and therefore absorption capacity. But this causes a lot of resistance for airflow, which also has an energy cost. We need to rethink how we can get the same amount or more sorbent ih the device, while also allowing for less resistance.

lingxkong commented 5 months ago

This is an idea relating to the intrinsic properties of how the sorbents settle based on the way the device is built. The chamber is a rectangular prism slab with the two long sides equal in length, similar to a square drink coaster. The slab sits on one of its thin sides, vertically, causing the sorbent to settle down toward the bottom thin side through the force of gravity. This idea has been documented in the #epiphyte channel on the Open Air discord.

Problem it’s supposed to solve: If the sorbent chamber is not entirely filled, any gaps will cause the air passing through to take the path of least resistance, particularly if the sorbent is powder form rather than pellets. We would like to force a certain amount of air through portions of the sorbent window, particularly at the bottom.

Description of idea/proposed solution: It’s a tunnel interfacing the sorbent window with the fan (there is only one fan at the output which pulls air through using negative pressure). The key with this tunnel is that it’s divided up into portions—maybe 4, 9, or 16 divisions so that each division gets its own window of sorbent to work on, i.e., pull air through.

(please excuse the hand-drawn) image

Materials: There is a supplier called TAP Plastics that I have access to. I can’t see why suppliers similar to McMaster would also have plexiglass or polycarbonate pipes, and I believe I have seen square ones. Mounting is a separate issue and I haven’t optimized it in my head—maybe a supporting structure from the bottom, or some L brackets to mount.

Potential technical difficulties and their workarounds: I think this idea will by no means go smoothly. I am already worried about implementation

See also this post in issue #11 for another angle for air flow-through.

mxbifurcations commented 3 months ago

image A search on "fluidized bed with vortex" shows a variety of designs made to move solid grains in a gas flow. A wood chips / dust collector works the same way. If hot air is blown the chamber could also perform the desorption ?