Rubber lining multi-media pressure filters 2

[coachk]

Anyone have experience with rubber lining multi-media pressure filters? In particular, thickness of the lining. The filters are to be used as pretreatment for an RO plant, and can receive water from 2 different sources: potable water with high SDIs, and seawater from wells.

 

[cub3bead]

I use 3/16" (4.8 mm) semi hard natural rubber for ion exchange vessels and filters. Equipment suppliers may offer epoxy linings but I have always been concerned about abrading the epoxy lining during backwash expecially when you have air scour capabilities. The rubber pretty much eliminates that concern.

Make sure you specify a spark test to identify "holidays" in the lining. You will get pretty agressive attack on the steel substrate if you have a pinhole especially when processing seawater.

Have you done pilot tests on the sorce waters to verify that you will be able to reduce the SDI with multimedia filters?

 

[coachk]

cub3bead,

Thanks for the response. I have the same concerns regarding abrasion of the epoxy lining, and have seen what were reported to be epoxy coated valve disks that failed miserably in seawater service....could have been a bad coating job, but I'd rather that not happen with these filters. On the flip-side, I have also seen rubber lined seawater strainers that had been in service for quite a while, and, when opened for cleaning and inspections, looked great. Filtration was pilot tested, and worked well. Thanks again.

 

[jherbert]

Rubber is banned for potable water,
and has been for a long time because
it supports growth of legionella.

cheers,

 

[tr6]

Plasite 4100 has bee used successfully as an epoxy lining for multimedia filtration in a number of offshore applications as pretreatment to membrane systems. The lining is durable enough so as to be not affected by abrasion issues. There are filters, with air scour, in the 12' diameter range that have operating history of at around 8 years without exhibiting any degradation.