I don't have any experience with nocturnal dialysis and sleeping, but as far as "sound" goes, I purchased an air purifier for my bedroom and I find it very difficult to sleep without it on. It drowns out other sounds like the A/C or the TV in the front room if my Husband is watching in there. It also helps drown out barking dogs outside.
I wish you luck. Sleep is important to us ESRD folks. We either want to sleep all the time (easily) or find it very difficult to sleep at all. That was my experience anyway. Actually, waking up was the hardest for me. Still is, actually.