Is this something that can be done when you live rural and want to to use the well water for drinking but it has a 71% nitrites in it after being tested?
It's possible that a reverse osmosis device might do it. There are devices made for the domestic market but I'm not sure they would be a very satisfactory solution. Most would appear to be targetted at people who feel their mains supply is not "pure" enough. Use the well water for the garden and use the regular supply to drink after all it's pretty cheap. See