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3.5 cents per sachet seems very expensive in bulk. A sachet probably only contains a gram or so, meaning these ingredients are being sold at $35/kilo. $3/kilo sounds far more reasonable, and it should be sold in 1kg containers and users instructed to use a teaspoon per large bucket.
(probably more than 1g per sachet, 4g as it says in the picture)
As hinted by the article this is not news. PG has been doing that for almost 2 decades by now.
I worked as an extraction metallurgist in semi desert mines and we used an aluminium based flocculant (alum) to clarify water in dams with rotating stirrers. Quite an old concept and not expensive.
Obviously it doesn't provide total purity, but it was a lot better than doing nothing.
Apparently even the ancient Egyptians knew about this: https://en.wikipedia.org/wiki/Potassium_alum#In_antiquity
3.5 cents per sachet seems very expensive in bulk. A sachet probably only contains a gram or so, meaning these ingredients are being sold at $35/kilo. $3/kilo sounds far more reasonable, and it should be sold in 1kg containers and users instructed to use a teaspoon per large bucket.
There seem to be two main use cases for this stuff. One is everyday disinfection of drinking water. For that purpose a large container might be more economical, provided that it can be kept reasonably watertight through three years of daily use. (1 gram per day per family means a 1kg container will last 2-3 years.) The other is emergency use in disaster zones for a limited amount of time. For this purpose a bunch of…
I wonder if it would have to stay in the packets or smaller containers to maintain its efficacy?