by Brian White
In October 1983, I saw something that changed my life. I was working in the Agricultural institute in Carlow Ireland at the incredibly boring job of distilling hexane for glc in the pesticides lab. Air bubbles sometimes went with the water through the cooling glassware and pipes. They wound their merry way through and I saw that the bubbles stopped water from passing even when they were quite long in a small tube. I saw it as a possible way of pumping water, using a very small head and yet being decently efficient.
It was in the back of my mind for several years. My first written record of using it is 13th of June 87 when I used a coffer jar pump of 7 chambers to pump water about 6 ft high into a 50 gallon barrel to water my garden. I noticed the pulser effect in December that year and abandoned the coffee jars! Just so much simpler.
The pulser pump (see the article in the October Issue) has been on the web for a number of years now and never received the response that I expected. Peer review (the basis of respected living science) hasn't come yet. People just don't seem willing to dig a 3 meter pit on the basis of my web pages.
So ... back to the Coffee jars! A coffee jar syphon pump is a hydropowered toy. Visiting friends and relations were really interested when I had one working. It worked on a head of 6 or 8 inches in a stream and pumped to about 6 ft in 7 stages. I used a bicycle pump to start the syphon.
Here is the coffee jar pump. The first diagram shows the part to make the suction. (And a valve setup to allow air to bleed into the device as fast as it is removed). In my first suction pumps I didn't have the valve and I just used a fine constriction (a pinhole) to allow the air to enter the suction section. Of course, a valve is much more efficient. Please note that the diagrams are not to scale. I have made a much larger version of this part too. With 3 inch diameter pipes for the water and going 6 ft high over the stream. I started that one using a bicycle pump with the plunger reversed to suck out the air and start the siphon running. The bicycle pump had the valve reversed so it would suck instead of blow. Suck out a little air and the pump starts! (You can also make auto start pumps but I don't want to complicate things too much!) I hope some of you make coffee jar syphon pumps and I would love to hear back from those that do.
And below is a diagram to show how the pumping modules work. Again scale is ignored. There is only one stroke controller and it contains the syphon that regulates the length of pumping strokes. Fill and empty strokes occur at the same time in all the modules. I mounted all the horizontal jars on "shelves" attached to a 6 ft 2 by 4 and I mounted the standing up jars on shelves on another 2 by 4 with 1 ft intervals between shelves. Raising one 2 by 4 in relation to the other got all the jars at the correct height in relation to each other. The animations are not perfect but hopefully they help. When the pipes are of clear plastic, the pump is very interesting indeed!
The device shown is just a toy. If you scale it up, I suggest you use an airlift pump operated by suction instead of the second of the 2 animations.
Technical tips! Valves do not need to be ball shaped like in the animation. My most successful syphon pumps actually had the valve outside the jar! I used the 2 mm soft rubber tube for the old type of bicycle valve and had a float in the outlet water from a pump regulate the flow to the pump. As the water sped up, the float raised a little and let air through the tube.
A modern bicycle valve and a float inside a custom made regulator part might work well. At the time my technical skills precluded a good internal valve. Another thing that might work is a scale type regulator. As the water rises in the regulator to the right level, it gets heavier, to the point that it tips the scale, opens the valve, lowers the water, closes the valve, etc , etc. AND you could use the outside the jar rubber pipe valve for that too. My point in putting in this article is that you might also make these suction pumps on a much larger scale. I made the suction generating part of 3 inch diameter pipes going to 6 ft high one time. That generated a considerable amount of suction. BUT obviously, using that device to produce suction in coffee jars or bigger containers is too cumbersome. Why not use it to generate the pulser effect in reverse? An airlift pump powered by suction, if you will!
Sure, you will need sturdy material and you will need some sort of valving and chambers at the top of the airlift pump to release water when a chamber fills and a valve at the bottom to let in air as fast as it is being withdrawn. But the complexity isn't that great and what you might have is a portable yet simple hydropowered water pump. One that you could set up somewhere in about an hour and remove just as quickly if needed. A commercial opportunity to be sure. Based on the same physics as the pulser pump but without having to dig a permanent structure.