@8606bdb4 I beg your pardon. I scanned the linked story 

https://www.soest.hawaii.edu/soestwp/announce/news/4m-for-marine-carbon-removal-nopp/ 

Which mentioned using quicklime and olivine among other things- completely missed the “Electrochemical” in  the oceanacidification.noaa link, which is weird being electrochemical is kind of my day job.

OK I looked at the EbbCarbon website. If I could change my question to “what do you do with all the HCl?”

Thanks. 

 @5b4f22a8 That's an excellent question. At our research project scale, there won't be much HCl and that's Ebb's job to find a place for it. If that industry ever scaled, it's a legitimate question that they need to answer. My interest is in developing MRV to make sure that the method is safe and effective once alkalinity is added to the ocean.