Good idea, I have seen a few DIY projects online of co2 reactors, something on those lines would do the job i recon..? But if i could like you say use some quick disconnects, which i already have, and stuff a section of the return pipe with some purigen for eg that would be easy + you would see the state of the purigen if i used some clear hose.. I may give that a go and see what the flow rate is like..