Christos Charisiadis

Christos Charisiadis did not come to water through the obvious door. He trained as a civil engineer specialising in hydraulics at the Democritus University of Thrace in Greece, the discipline of how water moves through pipes, channels and structures, and then did two master's degrees on water and wastewater, the second of them in Germany at Leipzig University. It was there, as he tells it, that he came in contact with an R&D professional who had a bright idea about brine treatment, the first time he had heard of it. From there, in his own words, it was a never-ending trip to innovation when it comes to treating high-salinity brines.

Christos Charisiadis works on the part of the water cycle most people never think about. When you desalinate seawater or recycle a hard industrial wastewater, you get clean water out of one side and, out of the other, a much saltier leftover called brine. He is precise about the word, because the industry is sloppy with it: when he says brine he means roughly 60,000 milligrams of dissolved salt per litre, well past the point where a normal reverse osmosis membrane (the standard filter that pushes water through a barrier salt cannot cross) simply gives up. That is the hard corner of water technology he chose, and the reason a whole zoo of exotic methods exists, from ultra-high-pressure reverse osmosis to membrane distillation.

Christos Charisiadis spent four years at Lenntech, the Dutch systems integrator near Delft that specialises, in his phrase, in dealing with hard cases, and his job there was the business end of brine: scouting more than ten brine and Zero Liquid Discharge technologies worldwide (Zero Liquid Discharge, or ZLD, meaning you recover essentially all the water and leave only dry solids behind) and matching them to the clients who actually needed them. He is refreshingly honest about why most do not. ZLD can cost three times as much to run as the cheaper alternatives, so unless a company is pressed by legislation or by its own water needs, it stops at 80 to 85 percent recovery and saves the money. His proudest project was a brutally complex brine, 10 to 12 percent salt with metals and organics in it, that took a year and a half and a liquid-to-liquid extraction trick to crack.

Christos Charisiadis kept moving toward the source of the problem. After Lenntech he joined the engineering giant Worley as a Brine Innovation Manager on the NEOM portfolio, working on concentrating the brine and recovering materials from the seawater desalination feeding Saudi Arabia's NEOM mega-development, one of the largest desalination programmes on the planet. Then, in 2024, he went out on his own and founded Brine Consulting, an independent advisory in Amsterdam that helps companies, utilities and investors turn saline waste streams into something valuable, covering brine valorisation, ZLD design, water reuse and the due-diligence that decides whether a project is worth funding. His conviction, the one that runs under all of it, is simple: every wastewater available can and should be treated and reused.

Christos Charisiadis is, by his own account, happiest when he is searching and trying to solve a riddle, a little bit like detective work, and the riddle that pains him most is at home. He points to a National Geographic piece on Greece's water resources and, coming from that area himself, vouches that his own water-stressed country is not taking care of its water, with what he calls a very immediate danger in the next five to ten years. That is the quiet engine of the whole arc, an engineer who fell for the hardest, least glamorous water on earth, partly because the places that need the answer most are the ones ignoring it. (Every fact here is anchored to his own words on my microphone and his public record, the way I source everything on my methodology page.)

“I strongly believe that every wastewater available can and should be treated and reused.”

Christos Charisiadis is, in short, a brine engineer who turned a thankless technical corner into a vocation, and who would rather recover the value in the water everyone else is paying to throw away.