Hello Hasan, I only know ...
Published by Gary Slenders, Principal Process Engineer
Hello Hasan,
I only know this as I design the covers and extraction systems for the odour control side of things.
The manual that you are after if I understand your question is the API Manual on Disposal of Refinery Wastes, 1st Ed published in 1969. Chapters 5 & 6 covers separators and Chapter 9 covers DAF Units.
You would need to approach the American Petroleum Institute directly to purchase a copy of the manual.
Regards
Gary Slenders
Principal Process Engineer - AOMC Pty Ltd