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 Welcome
to the "Think Tank" - our research & development division. Here we post ideas for new products
involving various water issues. This department is run
entirely by volunteers. It does not matter if you are an
engineer, machinist, designer, or simply someone who likes to
experiment with gadgets - if you like to tinker or invent stuff,
then WE NEED YOU!Below, you will find details about projects that are on the top of our list for development. As you submit more ideas, we will try to post them as best we can. If you can build a working prototype, then all the better. Our goal is to come up with items that are non-electric, non-motorized, and able to be reproduced and/or repaired in the third world. |
 We
had originally found this design in a book entitled "The Forgotten
Arts & Crafts" by John Seymour (ISBN 0-78945847-0). The
machine was referred to as the "Raplin Ice Maker", and the snippet
of text stated, "Before refrigerators were common, ice-making
machines could be found in many homes. The Raplin ice maker
was one of the many machines available. It froze water at the
turn of a handle, making a block of ice in about 20 minutes." Near as we can figure, the crank compresses a
chamber with some sort of gas (perhaps ammonia), which is then
released into an expansion chamber. As the compressed gas
expands, it rapidly cools and thus freezes the water housed in a
separate chamber. All of this in a unit about the size of a
sewing machine.The author of the book has passed away, and when you try to search for an actual machine on the internet, you will find a million listings for hand cranked ice cream makers. We were able to track down the original manufacturer: Messrs Pulsometer Engineering Co., Ltd., Reading England, Nine Elms Iron Works, Reading. In addition: Pulsometer Engineering Co., 1 St. Pauls Yard, Newport Pagnell, Buckinghamshire MK16 OEG. It seems that the Pulsometer company was mainly involved as an ironworks business that made parts and cars for the railroad. The company closed its doors in 1960, but seems to have been taken over by what is now the Sigmund Pulsometer Company, who were kind enough to send us this catalog description and picture. Another lead is a design called the "Audiffren Singrun Refrigerating Machine".This is something that can obviously be done if we could get a prototype in hand. Ammonia is easy to get in the third world, but it would have to be recycled inside the unit. If you are willing to put your brain, time and energy into a working prototype, that would be excellent. The use for such a unit is in a village being able to preserve fresh fish or game to keep for their use, and for them to be able to transport to other villages before spoiling. (top)
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A small, inexpensive solar still kit that could
produce between 1-5 gallons of fresh water per day is kind of the
"holy grail" of water projects. The idea is not to use solar
panels, since people in a third world setting could not afford them
or be able to replace them when they break. Most efforts have
concentrated on community-sized projects without much success.
We want to concentrate on families and individuals - just to supply
enough drinking water for the day. The standard approach is to
spread the water over a large surface area in the sun so it will
evaporate, then fall into a collection trough when it condenses.
That is good, but it takes up a lot of space. It is also
expensive and awkward if using glass. We were thinking of the
possibility of using a standard lens for eyeglasses (a lens blank
costs about 40 cents). The lens would concentrate a focused
beam onto a small amount of water, as in a narrow diameter copper
tube or something. The trick is to limit the fire hazard and
also to accommodate for the movement of the sun. Another
possibility is to do the large surface area thing, but with heavy
duty plastic that can be rolled up or folded to transport. The
benefit to this project is that through distillation, any water
source (ocean, brackish, muddy, contaminated) can be used to make
fresh drinking water.
(top)
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.jpg) Certain places, like areas of Bangladesh, have
problems with arsenic in the ground water. We want to develop
an inexpensive cartridge to remove arsenic that will attach to the
outflow of our bio-sand filters. We are not chemists here, so
we are not even sure how to evaluate results. Having talked
with some water treatment companies, we have heard at least 2
possible methods that would meet our criteria for appropriate
technology. One is to use a media that contains mixed shavings
of zinc and copper (ground up pennies anyone?). Apparently,
the dissimilar metals act as some sort of battery, and the metals
attract and bind with the arsenic. The other idea is using
rust (ferrous oxide) particles. We have read an article
whereby people added rust to arsenic-laden water. They
concluded that the ferrous oxide in the rust absorbed the arsenic.
They then passed the water over a magnet which removed the rust
particles from the water. Again, our idea is to put this into
a form of a cartridge that can screw onto a small pvc pipe to help
remove arsenic as water passes through on the way out of a biosand
filter.
(top)
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The "Afridev" is a manual lift action pump that is used in a lot of third world wells. It is a very good pump, but tends to be expensive, and not very portable (missionaries could not easily put one on an airplane to take with them to do a well project). Our idea is to make a portable kit with the essentials of the pump. The kit could then be retrofitted onto whatever pvc pipe you can find in the field (the trick is to make it able to fit varying diameters of pipe up to 4-inches/100mm - you never know what you will find in the third world). To get a better idea of how the Afridev works, click here for an instruction manual. (top) |
