Backyard Aquaponics
A place to discuss aquaponics

There are lots of different ways to isolate the algae from water, depending on what factor you are optimizing upon. The screen you mention would probably work.

You could just pump that algae-water out to a holding tank, and let the water evaporate off, leaving algae behind.

You could do it with an angled covering to get the condensate back for reuse.

I found a filter press that you can reduce a slurry into cake with that you can probably mfg yourself but getting the algae fine particulates condensed into a slurry or cake I had to rethink. The waste water plants use a flocculant to cause the algae to clump togather where a filter press can collect it. The plants use a sock over an auger to collect the dead biomass, then filter press it to a cake to dispose of. You wouldn't want metals type chemicals involved. I did some research on centrufuges as to what would work with specific gravity of 1.0 to seperate the algae from the water in a price range the average diy'er could afford, and all I could come up was used commercial juice clearifier centrifuges and used dairy milk seperator centrifuges. They started at 3 hp and were 3 phase 460 volt and such. What I was envisioning was something around 1/2 hp single phase that was self cleaning of the solids to a container and water return to pond or other container. All I could find in the smaller centrifuges were made for oil and were not self cleaning.
Here is a link for a filter press...expensive http://www.metchem.com/filter_press.htm
And here is a link for a small oil centrifuge which is oil pressure/flow driven. http://cgi.ebay.com/Bio-Diesel-Fuel-Cen ... 7C294%3A50

You may be able to control the speed by inlet flow to get good seperation but it only collects 10 oz at a time.
You may want to watch the local farm auctions for a dairy milk seperator or juice centrifuge to convert where they are self cleaning continuous duty.

From what I understand centrifuges use to much energy. Perhaps I can find a string type algae.

I am unsure of the particulate size you are looking at Dan but when I was making papercrete I just used shadecloth draped over a frame. If you make a U shaped drape and pumped from one end this seems the simplest. As it builds up it would create a finer and finer filter.

Forget the algae, it takes a large amount of room to get enough mass. Alage comes and goes, maybe due to that annoying chemical that kills itself type of thing.

Go for the duckweed! Duckweed comes and stays for the long haul. A quick internet search yielded some articles about using duckweed as fuel. Duckweed, good for food, fuel, shade, fish tank filtration, what else? Maybe we could put duckweed into paintballs, hahaha.

How much oil is in duck weed.. Well anyway, I have tried to grow it and not had any success.

I would really enjoy reading the pdf which was linked in the initial post, however the link appears to be broken, could anyone repost it?

Duckweed for fuel is something I had never considered. Interesting.

http://running_on_alcohol.tripod.com/id31.html

Multi-purpose crop. Maybe you just need to try another strain DDM. I got some from a nursery and it died on me. So I got some more cos figured I had done something wrong. In between I found some at the edge of my river and put that in. Is much smaller and greener than the blue-green stuff I had brought from the nursery. It took over. Figured my water pH has something to do with the first lot not making it. I am considering growing it in tiers.... going vertical with trays to get enough growing. Just want to use alternate energy to lift the water up to the top and it can gravity feed down to the trays below some way without those little plants travelling with. Be nice if I can have it off the side of my AP system some way. Still needs thought as an idea.

Its pretty easy to make hydrogen and carbon monoxide from anything that will burn. I find it much faster and efficient than making alcohol or even algae oil. Of-course duckweed or algae when dried will burn and that's the point. Any fast growing bio mass will do. The only real source of energy is the sun, so the faster the plant grows the better.

Just a though.. It would be interesting to build a water pump that uses burning hydrogen in a cylinder to lift water. No mechanical linkage or cam shafts. It should be very efficient. If only I had access to a machine shop.

How would you access the hydrogen? I was going to convert my car to hydrogen as a fuel cos a local guy was building something that took water and split out the hydrogen. But he pulled out. I think big business got to him or something. Sounded so fantastic. Could put your mouth to the exhaust cos the by-product was so harmless.

The output from this process would have co2 and water in the output. It would not poison you.

The only way to use in in a car is to compress it. To be usable you need at least 3000 psi. Which requires a 1500 pump.

OR if you dont mind the weird looks from people you could use a $5 weather balloon like this: http://www.youtube.com/watch?v=brpJExF7iXI&feature=channel_page

1000 cubic feet of H2 and CO is the same as about 3 gallons of gas. These gases do not liquefy so they require high pressures to be in a convenient size. I plan on using this gas mostly at home in a generator. However, Im not to good to strap two 6 foot latex weather balloons to the top of my car either.

God willing, I will get to the point that I can buy a 3000 psi compressor and some scuba tanks so that I can run my cars on this gas.

This may be redundant, but what mods would you have to make to run 100% H2?

A "No Smoking" sign ...

Salvinia is another plant you could try. Fast growing like duckweed but with more mass.

"This may be redundant, but what mods would you have to make to run 100% H2?"

Aside from the carbrettor/ air intake manifold and adjusting the timing probably need an upper cylinder lubricant drip, unless its a rotary engine.