Millbank Bags

[hedgerowpete]

i can filter two gallons of wine through it in about an hour, water would go through the same, when i filter water camping wise we always hang the sock up first and then pour the water into it so we dont contaminate the outside of the bags, i have seen far to many people with mill bags sloush them through the stream and then hang them up.

 

[Totumpole]

Well there we go! Might have to buy one of those as well now!!!

 

[Lupin Rider]

You can get filters off of ebay that are used for making bio-diesil that are as fine filterer as a milbank if not finer but unlike Hedgerowpete I still wouldn't trust it to get all the nasties out and would still boil it to make sure it was safe to drink

The pharmaceutical industry uses step downs from 10 to 2 to a final o.2 micrometer filter to sterilise fluids. This scale filter removes all bacteria and viruses. It however needs more head ( pressure drop) than we use with a milllbank.

One of the reasons the millbank works so well is that the really fine clays and other bits of organic mater clogg the pores and form a thin filter cake. This reduces the particle size that can get throught the bag enhancing the separation.

Yeasts as an micro organism are rather large so easier to catch than bacteria and viruses.

Eventually bacteria will grow through a sterilising filter so the industry then steam sterilises or replaces the cartridges.

For many separations of powder from liquid ( a process step in most drug manufacture) the filter cake or heel on the filter is the key part for the separation and great care is taken to ensure it is built each batch processed.

Bushcrafting in the field rather than a one step to sterile doing a two stage process is still the easiest and best way, a "relativly" course filter with a fining filter cake followed by a boilup. The boilup also has benefit of being a pokeyoke (safety step) in that any bugs that get through your bag or from you hands also get zapped.

John

 

[Retired Member southey]

All the filter stage Is doing this context is removing as much turbidity so as to make the boiling more effective, I don't want the process to take to long, or to have to guff about with random kit, I also want my filter to be fine if left in my bergan with the water bottle, a milbank. Bag fills the filter slot for me as it works, but you could just use any piece of fine weeve cloth. Like a tee shirt.

 

[BillyBlade]

The pharmaceutical industry uses step downs from 10 to 2 to a final o.2 micrometer filter to sterilise fluids. This scale filter removes all bacteria and viruses. It however needs more head ( pressure drop) than we use with a milllbank.

One of the reasons the millbank works so well is that the really fine clays and other bits of organic mater clogg the pores and form a thin filter cake. This reduces the particle size that can get throught the bag enhancing the separation.

Yeasts as an micro organism are rather large so easier to catch than bacteria and viruses.

Eventually bacteria will grow through a sterilising filter so the industry then steam sterilises or replaces the cartridges.

For many separations of powder from liquid ( a process step in most drug manufacture) the filter cake or heel on the filter is the key part for the separation and great care is taken to ensure it is built each batch processed.

Bushcrafting in the field rather than a one step to sterile doing a two stage process is still the easiest and best way, a "relativly" course filter with a fining filter cake followed by a boilup. The boilup also has benefit of being a pokeyoke (safety step) in that any bugs that get through your bag or from you hands also get zapped.

John

Thanks for taking the time to post that, it backs up what I learned, and then forgot, on course years ago.

We asked the instuctors why people still used the millbank bags instead of other kit, and that part about the fine clay into the pores and other bags having bacterial growth is pretty much the answer we got.