Which of the following is not true in case of closing the top of the vessel?

At what pressure is the air blown during cleaning?

Which of the following causes thickening of the biofilm?

What would happen if the tube settler is inclined greater than 60 degrees?

Which of these require a flash mixer prior to it?

Even by high-rate of backwash, efficiency of cleaning is poor.

While designing a blower for backwash for dual media filters without air scouring what is the velocity considered?

What is the surface area of the plastic random packing high specific surface area packing material used in trickling fil…