Bio-Sand Filter

[LIL COO COO]

I was wondering if any of you guys or gals had any experience with a Bio-Sand Filter. From my understanding, it is able to remove 95% bacteria and virus and can last for 10 years. Amazingly enough, it only costs $35. I saw a little blurb in a past Rotarian Mag.

Seems to me that this is a great thing. What are your thoughts?

 

[JCavSD]

Is this for small scale home use? I don't have enough info on the item you're asking about to make a call on this. However, I do know that sand filtration is frequently used in large scale water treatment operations. Any filter media needs to be replaced and/or cleaned (backwashed) on a fairly regular basis. Media that isn't maintained well can create water quality problems. Ten years seems like a long time.

 

[LIL COO COO]

JCavSD,

Good question, I am assuming so because there is a picture of a woman holding a baby with one arm and pouring bad water via gallon jug into this bio-sand filter.

Additional Info:

November 2009 Rotarian Magazine

Title: The Virtue of Small Change: Rescuing the World Costs Less Than You Think
Author: John Conroy

Page 41: "The numbers are astonishing: One in three people worldwide laks access to clean water,...The HydraAid bio-sand filter removes all parasites and 95 percent of bacteria and viruses. It uses gravity as a power source, has no moving parts, and lasts for at least 10 years. Made of plastic, it weight just 8 pounds. For $32, you can buy yourself two bottles of water a day for about two weeks, or you can buy one bio-sand filter and deliver pure water for a decade to an entire family."

Page 59: "Bio-sand filter: A concrete or plastic box containing layers of sand is used to trap and eliminate sediments, pathogens, and other impurities in the water. A layer of cicroorganisms on top of the sand captures disease-causing bacteria as the water is poured over it. Larger particles are removed as the water passes through the sand layers. (Higher initial costs than disinfection.)"

I have never heard of such a thing. It sounds so spectacular that I don't know if it is fact or fiction. If it is true...I am not sure why I don't have or why I haven't made one for myself let alone have the parts to make one.

 

[Bushman5]

it works like a sand filter does in an aquarium. Water goes thru the filter media, and healthy colonies of bacteria build up, which kill off bad organisms. HOWEVER.........if "dead zones" (areas devoid of healthy bacteria and oxygen) develop in the sand, bad bacterias and gases can build up, hence the need for the occasional backflush and cleaning off of the first layer of crud/bacteria trapped in the media. (if used on a continous basis like water treatment plants). I dont know if occasional use would create these dead zones of bad bacteria.......

some interesting links:

http://www.hydraid.org/

http://www.biosandfilter.org/biosandfilter/

http://en.wikipedia.org/wiki/BioSand_Filter

http://www.cawst.org/index.php?id=128

biosand filter invented by Alberta Canada guy:http://www.abheritage.ca/abinvents/inventions/inv_hw_biosand_water_filter.htm

 

[JCavSD]

Effective and extremely inexpensive. If it sounds to good to be true...it probably is. This is the same basic setup as used in most conventional water treatment plants. The difference being that treatment plants also post chlorinate because conventional filtration doesn't do the the trick alone. I don't know, seems like a good partial solution.