If you want to hide a partition in nautilus (which uses udisks2), you can do that easily by setting the UDISKS_IGNORE environment to 1 in an udev rules file.
The following example hides all the partitions that have a logical volume name that finishes by “-sbuild”:
$ cat /etc/udev/rules.d/99-hide-lv-udisks.rules ENV{DM_LV_NAME}=="*-sbuild", ENV{UDISKS_IGNORE}="1"
After that you need to run “udevadm trigger” as root, the disks should then immediately disappear from nautilus.
You can use “udevadm info” to see the different environment variables that could be used to identify a disk/partition.