The new way of mounting a disk image created with dd, dd_rescue, or ddrescue has become much simpler than before, all you need now is to issue the command
losetup --partscan --find --show disk.img
then above will tell you what loop device is being used, let us assume it is /dev/loop0, right after, a quick fdisk -l should show you the partitions, in my case, i have /dev/loop0p1 and /dev/loop0p2
mount /dev/loop0p1 /mnt
now, the first partition is mounted, to reverse this, you will need to first unmount /mnt then, you can delete the loop device with
losetup -d /dev/loop0
And you are done