During preliminary work in 2005, we developed and tested a prototype seafloor Free Ocean CO2 Enrichment (FOCE) system, using acid injection with controlled loop pH feedback to maintain a specified ΔpH within a two-meter diameter ring. Several aspects of the early work have shown promise as well as strong interest from the science community. The prototype results clearly showed that control was possible using a pH feedback loop, but that a new design was necessary to address issues discovered while performing in situ testing. Principal among these was the need to allow time for chemical equilibrium to occur due to the slow kinetics of the carbonate system. The primary developments needed are to extend the work to actual CO2 enrichment, with all the complexity that requires due to the physical characteristics of CO2 and the potential for CO2 clathrate hydrate formation, and to account for the significant kinetic lag times for full development of the pH signal.
FOCE Prototype during Tank Testing - Prior to In Situ Experiments
Next: Prototype DesignQuestions? Comments? Please contact Edward Peltzer.