Can i recover data from a Nandroid Backup without the original device?
That would indeed be possible. There are several apps which are able to extract parts of a Nandroid backup, e.g. Titanium Backup or ROM Toolbox.

Apart from that, depending on the format used by your Nandroid backup, you can either mount them as loop device (disk images) or unpack them (tarballs) to invesigate/access all contents.

For further details, I'd recommend a look at our nandroid tag-wiki – and especially follow up to:


Restore only part of nandroid image
Extract App Data from Nandroid / CWM Backup