The diluted brine goes out to sea. It's less harmful than dumping the concentrated brine you had before, with the bonus that you got some power out of it.
The concentrated waste probably gets disposed of rather than trying to get the remaining water. You treat it like the results of a waste treatment plant. You might dehydrate it a bit, just so you don't have to ship the water, but you probably won't try to recover any more water than you already have.
The concentrated waste probably gets disposed of rather than trying to get the remaining water. You treat it like the results of a waste treatment plant. You might dehydrate it a bit, just so you don't have to ship the water, but you probably won't try to recover any more water than you already have.