How to design a TF

[dhot]

I am in charge of designing a Trickling Filter for a WWTP and have a number of books but none make sence. It is in a Cold climate and has a 0.24 mgd fdesign flow. The concentration is weak also 37-60 mg/l. Any anformation will be a great help. Thanks

 

[bimr]

In general, trickling filters are suited for colder climates. Have you considered altlernatives?

 

[dhot]

Yes I have considered an SBR system but it may not work because of the low concentration of the effluent. and the low flow. It will end up decanting solids more than usual.

 

[bimr]

Correction to my previous post. Trickling filters are not suited for colder climates.

Have you looked into the membrane processes? One of the advantages of the membrane process is the ability to retain the solids.

One of the problems with a conventional wastewater process is that it will be difficult to retain the solids using a clarifer when the system is not operating under optimal operating conditions (such as the cold and low BOD loading).

 

[dhot]

I knew what you ment. That they are not suitable for the cold. I will look into the membrain. This plant is small really small. Theplant maneger is also the water manager, road mng, mows lawns, removes snow, he does everything for this small town. To get to the point I want to make the plant as simple as Possible. Right now he thinks his plant runs fine but it is just by dumb luck it is meeting requirements. It has 60's technology and 3/4 of it doesn't work. It is a man made pond and he adds Cl2 to.

 

[nackra]

I've seen TFs in Illinois (Central and Southern) "covered" to protect from extreme cold - back in the '80's.

Temcor dome used w/ infrered heaters in Central IL

Pole barns w/ infrared htrs in Southern IL

Suspect now that other innovative technology w/ smaller footprint is more affordable.

 

[ch81pc]

What about an N-SAF unit(cross between AS and a TF

http://www.processingtalk.com/news/ses/ses120.html)?

I've used these during cold weather when we've had prblems with traditional TF geting too cold. They hold the heat much better (no super cooling for sparge holes, bulk treatment rather than thin film, if cold is still a problem the aeration air can be pre-heated a little.
If you still want to use TF's then I would use trough type arms (no super cooling associate with sparge jets),extend the walls 6' aboe the level of the media to lessen wind chill, solid filter walls with vent columns for ventilation instead of semi open sides is good and also avoid using plastic media as it has a low latent heat.