You can use an insert statement with a DB link created for the remote database. For example:

Insert into your_remote_table@remote_db (id, blob_column) 
    select id, blob_column from local_table;

In this case, I am assuming the DB link remote_db is created at the source database so that you will execute the above statement from the source database.

If the DB link is created at the target database, then below is an example of executing the statement from target/remote database:

Insert into local_table (id, blob_column) 
    select id, blob_column from your_remote_table@remote_db;

This is as simple.

Please let me know if you are facing some specific issues.