Metered filter backwash?

[Relevante]

Hello everyone,

This is my first post, but I've been reading here for a long time now. Thanks for all the great info.

I'm about to undertake either a rejuvenation or replacement of my currently out of service well filtration system. I'm waiting for my KAR test kit, so I'm sure I'll be back with more specific questions once those results are in.

In the meantime, I have a general question. It seems that metered control valves are very popular for softener regeneration but not for filter backwash. Why is that? It seems to me that flow would be a really important factor in optimizing filter backwash interval. Is it about cost and simplicity or is there some reason that a timed interval is just better with filtration media? Does anyone do it?

Thanks!

Nick

 

[ditttohead]

Filters are too widely varied to have a simple answer.

Carbon filters are absorption based so reclassifying the bed at least once a month is important to remove accumulated sediment and to prevent fouling and pressure drops.
Iron reduction medias rely on oxidation which can quickly foul the media so more frequent backwashing is important. Typically 3-5 days.
Sediment reduction filters need to backwash prior to the media becoming heavily fouled so weekly or bi-weekly is very common but it really depends on the amount of sediment. Differential pressure switches can also be used but this is rarely done in smaller applications.

So on and so forth.

Meters are fine on these types of systems but in general we run the day override well before the wildy guestimated gallon capacity is reached. A meter does add a little bit of cost and complexity. We stock and sell both but the vast majority go out as timeclocks.

Softeners are "absolute" calculable gallon rated and use a consumable (salt) so high efficiency is very important and meters not only make sense but are required in many municipalities.

 

[Sponsor]

 

[Relevante]

OK, thanks, that makes sense.