Published by Ali Salmani, Process Engineer
I'm designing aDAFsystem forseawaterpretreatment. Iwould appreciateif youtell me that how much I consider the range of air-to-solid ratio (A/S)?
Some of my data for designing are as follows:
Q=20,000 m3/d
TSS=50 mg/l
Dear Sir, in our experience it is highly unlikely that you need a DAF system to produce a water suitable for a following Reverse Osmosis membrane plant. Direct filtration using pumice with a very small dose of a primary coagulant is more than able to produce a water which is acceptable to membrane manufacturers. Direct filtration would be a much simpler and cheaper alternative. However, if you do wish to continue to go down the DAF route then please let me know as we have access to high rate and simple to operate DAF technology.
Published by Edward Blackmore, Techfil (Europe) Ltd - Director - Water Treatment Division
Sir, thanks a lot for your quick response.
Published by Ali Salmani, Process Engineer
Air blowers for the DAF system should be designed to deliver 8 to 10 bars!
Published by Nikolay Voutchkov, Water Globe Consulting, LLC - President
Hi Mr. Zolal: The recommended air to solids ratio is 0.75 kg of air per 1 kg of dry solids. If your TSS is 50 mg/L - you would have 20,000 m3/day x 50 mg/L /1000 = 1000 kg of dry solids/day. Therefore, you would need to design your air blower system to deliver 750 kg of air/day.
Published by Nikolay Voutchkov, Water Globe Consulting, LLC - President