fdisk -l /dev/sdd
Disk /dev/sdd: 250.1 GB, 250058268160 bytes
255 heads, 63 sectors/track, 30401 cylinders, total 488395055 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x90909090 
Device    Boot  Start   End   Blocks    Id   System
/dev/sdd1   *        2048     2099199     1048576   fd  Linux raid autodetect
/dev/sdd2         2099200     6293503     2097152   82  Linux swap / Solaris
/dev/sdd3         6293504    69208063    31457280   fd  Linux raid autodetect
/dev/sdd4        69208064   488394751   209593344   fd  Linux raid autodetect

$ sudo mkdir /mnt/old_hdd 
$ sudo mount /dev/sdd4 /mnt/old_hdd 
mount: unknown filesystem type 'linux_raid_member'

$ sudo mdadm -A -R /dev/md9 /dev/sdd4
mdadm: /dev/md9 has been started with 1 drive (out of 2).

$ sudo mount /dev/md9 /mnt/old_hdd/
$ mount | grep ^/dev/md9
/dev/md9 on /mnt/old_hdd type ext4 (rw)