We have had a very successful season with our outdoor contactor prototype. After our installation and start-up procedures in August, we were able to accumulate well over 500 hours of air ingestion as we progressed through packing conditioning and CO2 absorption stages. In October, we were able to run un-interrupted CO2 absorption - with our regeneration system maintaining equilibrium liquid conditions - for several days at a time. We have much more long-duration testing scheduled for next summer, but we all feel like we’ve gained a great deal of practical experience already. We’ve operated our contactor through hot summer weather, dusty fall days, and even sub-freezing nights – and thus far, our performance data is very encouraging. We have exciting results on several of the key aspects that we designed this prototype to test:
- We were able to control the quantity of “drift” (small liquid droplets in the outflow air) to roughly 5% of the health and safety restriction for indoor respiration! We did this with careful deployment of commercial drift eliminators and a few of our own contactor design innovations.
- We validated our patented “pulsed flow” operation method for air contacting. So far we have been able to reduce fluid pumping requirements by a factor of 10 (with respect to continuous flow) while retaining over 80% of maximum CO2 capture.
- We’ve confirmed the low frictional resistance (pressure drop) of our air contactor and the advanced packing we’re using. On a per-surface-area basis, our advanced packing offers less than half the resistance of traditional steel packing products from gas scrubber columns!
- We have measured CO2 absorption rate at temperatures ranging from below 0 C to over 25 C, and achieved multiple days of continuous operation on several occasions.
- Thus far, no major performance reductions have been observed from the build-up of atmospheric contaminants in our liquid. We aim to gather more data on this effect over several months next year.
We are now taking our prototype off-line for the winter; we have a lot of analysis and refinement to implement from this summer’s efforts, and we have our many other projects to advance over the coming months. Next spring we will begin further operation of our prototype, and we are even hoping to test the completely new, low-energy regeneration system that we have been working on! -GH.