This will save millions of lives: LifeStraw

[Moonbear]

Something is better than nothing, for the time being. Send them out by the billions, I say.

At $3 each, if someone had $3 billion to spend on these things, surely it would be better to build water purification systems than just provide a temporary measure allowing people to drink from contaminated water sources.

As Astronuc points out, though, the bigger limitation is political. Having the money doesn't mean it gets used for the intended purpose or that aid is allowed passage to the people who need it.

 

[Ivan Seeking]

The problem is that infrastructure is not a one-time charge, nor is it a localized problem to get water to all who need it. The demand for clean water is a global issue. You could not otherwise provide clean water to a billion people for three billion dollars. I would bet that the bill for water systems globally would amount to trillions.

A personal note: We are on a well and live in an area that has bad water - sulfur, iron, iron bacteria. Our twenty year chlorinated treatment and filter system [for one house] cost me about $10K to purchase, and probably another couple of hundred dollars a year to maintain. The total installation [building and cement work, power, permits, plumbing connections etc] cost about $20K.

 

[Astronuc]

I think preventing or mitigating contamination of water supplies would go along way to reduce water borne diseases.

One may remember wells that would dug in Bangladesh years ago. Everyone thought - Great! - Fresh water. What they didn't anticipate was the high levels of Arsenic in the water.

http://www.eng-consult.com/arsen.htm
http://www.sos-arsenic.net/
http://www.sciencemag.org/cgi/content/abstract/298/5598/1602
http://web.mit.edu/newsoffice/2002/bangladesh.html

In addition to the wells, they needed appropriate filtration to remove the arsenic, or they need to find well sources without arsenic contamination.

http://www.columbia.edu/cu/news/05/02/aresenic_test.html

 

[Ivan Seeking]

The need for clean water must be addressed on a global scale, but the LifeStraw will start saving lives as soon as it arrives where needed.

There has been a huge breakthrough in reverse osmosis systems that reduces the energy demand significantly. It involves a spinning filter technology that reclaims energy previously sacrificed. Does anyone know the name? I need to search... but it is exciting because energy is the problem here. I'll try to find a link.

 

[Ivan Seeking]

What I saw may be related to this:
http://www.osti.gov/bridge/servlets/purl/761675-7IByYO/webviewable/761675.pdf

but I think the application was a hybrid of this with traditional reverse osmosis. The energy demand was reduced by something like 60%.

 

[Ivan Seeking]

I think this is it.

Pump Engineering Inc provides energy recovery turbochargers: Hydraulic TurboCharger for sea water reverse osmosis, High Pressure TurboCharger for gas processing, and Low Pressure TurboCharger for brackish water reverse osmosis

...The Advanced Technology Turbocharger recovers hydraulic energy from the high pressure concentrate (brine) stream in the reverse osmosis (RO) process and transfers that energy to a feed stream. That feed stream may be seawater going into a single stage RO membrane block, or it may be first stage brine stream being boosted in pressure for a second stage membrane block for further recovery of permeate. This unique approach offers many advantages to the RO designer and users.

Advanced Technology Turbocharger Background
Like the previous generation PEI Turbos, the Advanced Technology Turbocharger transfer pressure energy from one liquid stream to a second liquid stream. However, with the use of new technology the Advanced Technology Turbocharger does this energy transference much more efficiently. The Advanced Technology Turbocharger consists of a pump impeller section and a turbine rotor section. Both pump and turbine sections contain a single stage impeller or rotor. The turbine rotor extracts hydraulic energy from the brine stream and converts it to mechanical energy. The pump impeller converts the mechanical energy produced by the turbine rotor back to pressure energy in the feed stream. Thus the Advanced Technology Turbocharger is entirely energized by the brine stream. It has no electrical, external lubrication, or pneumatic requirements.

The turbine rotor depressurizes the brine while extracting the energy in the form of high speed rotational torque. The brine, depressurized up to 5psi (brine exhaust can be any value, even hundreds of psi) is exhausted to the discharge piping.

It is readily apparent that the reduced discharge pressure of the high pressure pump will have a large effect not only on reducing operating cost, but also on reducing both initial capital and maintenance cost. [continued]

http://www.idswater.com/water/us/pump_engineering/Hydraulic_turbocharger/105_0/g_supplier.html

 

[Astronuc]

Thanks for those links Ivan.

A relevant article - http://en.wikipedia.org/wiki/Water_crisis

Inadequate access to safe drinking water by over 1.1 billion people

Sometimes oceans are mistaken for available water, but the amount of energy needed to convert saline water to potable water is prohibitive today, explaining why only a very small fraction of the world's water supply derives from desalination.

 

[Ivan Seeking]

In light of the current crisis in Haiti, I wanted to give this thread a bump.