Retrieve FaceBook primary emails by UIDs or user names

I have a list of Facebook UIDs and user names and I need to retrieve them to primary emails (Gmail, Hotmail, etc, not the abc at facebook dot com). They are currently stored in a MySQL database on a web server (Apache, Php >5.3, JS, Java, python, MySQL). The process would work like this: 1. by a launch form a "row-id range"; a "step-block number" (rows to process) before a "sleep time"; a "rows total to be processed" number; an "after this date" value would be set; 2. the application would do a select in the database by date and catch the step-block numer rows, process them then take a sleep action for the time set before, then run for the next block, until the rows total value is reached; 3. each new (retrieved) email would be added by update a specific field for the same database row. Before the work would be accepted as done, I will send some parts of the original database file with some UID from Facebook (owned by me or by colleagues) to test out the application. Hence in case of faults or fake results the work will be rejected.