Thread: Liquid gas SEPERATION...gas permeable..liquidimpermeable

Hi there ....

am trying to release controlled amount of air (bubbles) through a grid of vents at the bottom plate of a

tank filled with liquid .......was banking on surface tension to keep the thick liquid - silicon oil from
entering the 121 vents at the tank bottom (.25mm each)
turns out my naive ideas in physical chem. were wrong ......

details and drawings are downloadable at....http://www.4shared.com/file/3153539/5f33ff0d/sos.html

the liquid is entering the vents at the tank bottom ......seems i need one of the following...

some kindav separation membrane to allow only air passage (air passage has to be uniform all over the

grid)
OR
another liquid thicker than silicon oil under silicon oil ....not entering the 121 (.25mm) vents
OR
Some special air liquid interfacing non return valve to let air thru but block returning liquid etc

anything anyone has to add....or detail in the above?.....


I would be extremely grateful for ANY kind of help or guidance ......these are urgent and desperate hours

do support......deadline only few days away...

cheers
HK

:? an air filter that doesn't let any water get trought.. ehh.. hmm..

let me think, still my first thought is that it would be close to impossible. Or you would have to leave a space of air between the points so the bubbles can first get out into a big space of air and then be filtered...

...the air is goin from below into the tank ...the liquid is attemting to crawl into spaces like the air vents themselves (i tired.. .05mm ...it still found its way danm)......

but u see atleast the directions are opposite ths the filter analogy dosent work ......ther must be a way...thiking hard...maybe a unidirectional membrane or valve .......but festo n other guys say no such valve is ther for liquid air interface........thiking thikin........grrrrrr

teflon has good surface resistance.........but i think all these forces get a little too skewd for a layman at small distances etc ......neways next am trying to see how the liquid behaves (since its an oil..silicone oil).....if i have smaller..... .18 mm vents made of teflon tubing ......

wat is surprising (to a naive computer engineer like me :-p) that the liquid after being soo thick (its 2xthicker than house hold honey)...can crawl into .05 mm spaces.......even though the colum of air underneath is not displaceable (the solenoid valves close after firing and trap the air column)...still the liquid manages to crawl and press down the air... :-(

himanshu1khatri, what is the air pressure ? If you inject the air under a certain pressure, no liquid can come out at the same time.

the pressure will be between one and 3 bars....but at the same time as a stree testing things it shud be robutst for powerfailures etc..