Amount of diffuser discs at the base of an SBR basin?

How can I calculate the amount of ceramic diffuser discs needed for aeration at the base of the Sequencing Batch Reactor (SBR) basin?
What is the oxygen transfer of a single diffuser disk?
I want to make a grid of diffusers at the base.

The parameters are:

• Flow rate: 4000 m3/day
• Tank depth: 6 m
• Oxygen required: 3920 kg/day
• Aeration time: 14 hours/day
• Oxygen transfer efficiency: 36%
• Average OTE: 15%
• Average oxygen transfer rate: 3.7 kg/hr