What is the fastest way to force hdd to reallocate bad sectors and discard the data?

Solution 1:

You will need to find an older computer you can hide in a corner to let these programs run. If the drive is lightly damaged it can finish in <2 hours depending on the size of the hard drive.

If you set dban (dariks boot and nuke) to 2 or 3 passes it might be faster. Maybe mhdd (with remap turned ON)

Depending on the size of the hard drive, it does not like multi-TB hard drives. Spinrite from grc.com.

All 3 methods are set and forget. Check it a couple times a day to see if they are done.

Solution 2:

Your time is worth more than the drive, if your employed by someone im sure youve cost your employer more in salary Time than the cost of a new HD. Just get a new drive and copy over whatever data you can. If you have a backup (and you should) just restore the drive via that.