Yes. The CC Cloud Connection includes the ability to import books from calibre libraries stored on the device either in main memory or on an SD card. See CC Settings / Cloud Connection / Cloud Provider / Library on device or SD card.
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For purposes of the "local library" connection, a "calibre library" is defined by the presence of the file "metadata.db", which is calibre's database. If you put that file in a directory on an SD card then CC's Cloud Connection will be able to see it as a calibre library. However, it won't be a useful cloud library (providing ability transfer books to CC's library) because none of the book covers or files are there. To make it useful, simply copy the calibre library directory on your PC to a sub-directory on the SD card.
Don't put the calibre library in the topmost (root) directory of the SD card; CC won't find it there. Don't pick and choose what you copy -- copy everything in the calibre library. When you are finished you should have a directory on the SD card containing a lot of author directories and the metadata.db. This directory is the one to use as the "calibre library on device or SD card".
Note that CC treats this library as a source of books, just like Dropbox or other cloud providers. It cannot be used as CC's library.
If you get "Database corrupted" errors then there is a problem with CC using the SD Card for temporary storage. Try telling CC to use main memory for temporary storage by checking the CC option Settings / Connecting to calibre / Cloud Connection / Save cloud cache in main memory.