Serp belt problems

I have a 92 lincoln towncar, with 182,000 miles that is giving me fits. About a month ago the serpentine belt broke. I thought it was no problem replaced it and then about a week ago the new belt broke. I thought it was a bad belt, but the broken belt had drag marks on it and it was twisted, it appears that it got hung up on a pulley and snapped. All the pulley's except the crankshaft rotate free and easy. The tensioner seems to be plenty tight and gives good resistance when engage to put the belt on. The altenator pulley squeaks and I thought that was the culprate, but I took it off and took it to a very reputable generator shop where they put it under a load and told me that there is no way that it broke the belt. The only other abnormality is that the ps fluid leaks, but the ps pump rotates. I don't know were to go next. Please help.