Beaching in media during backwash - High Rate Open Gravity Filter

[LukeOPM]

Hey All,

Beaching issues in HROGF, any likely suspects to investigate prior to heading to site?

Cheers

 

[LukeOPM]

I should mention, there is apparently no blockage or pressure irregularity in diffuser arrangement.

 

[ashtree]

The first thing I would check is the air bubble pattern during the air scour assuming it has this feature. That is despite the statement that there is no irregularity.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[LukeOPM]

Hi Ashtree and thank you for your suugestion. I am on site now and can confirm the bubble pattern is as perfect as i've seen anywhere else.

I am starting to wonder if it is the dynamics of the inflow of raw water into the filter itself as it is only happening in the far end of the filter.

 

[ashtree]

Does the water enter the filter via the backwash trough during filtration operation or is there some other inlet port?

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[LukeOPM]

Through the backwash troughs

 

[ashtree]

Okay a couple of questions.

Is this a multiple filter installation?
If yes do the other filters have the same issue?
Do multiple filters return to service at once?
Is the backwash trough level- so that the overflow during refill of the filter is consistent along the length of the trough? If its not it might be favouring the area above the beach.
Have you stood there and watched it during the complete filter backwash cycle?
Can you stop the backwash sequence at the end of each step to see if the beach is better or worse? This might tell you when the media is being disturbed.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"