Joy,
I've been critical of a company that wants to commercialize the culitvation of algae to absorb carbon dioxide from (especially coal-fired) power plants (and other industrial processe) because they were showing off these simple design, but horrendously expensive large, clear, acrylic tubes as "bioreactors". It just wasn't practical for any kind of scaling up to commercial viability.
Then I discovered that the same company had come to their senses when it came to real world practical implementation of their intent. At a "pilot plant" next to the Arizona "Red Hawk" generating plant, they built greenhouses and filled them with hanging plastic bags. Now that sounds like it was incredibly stupid, at least if you think of it as individual plastic bags. That, fortunately is not what they did.
They formed the plastic bags from some clear polymer film (quite possibly polythene, but they have not mentioned the specific material in anything I have seen), but the "bags" are structured much more like the air mattresses, consisting of channels that follow the width of the surface, then the end is open to the next channel, and so on, down to the bottom. Of course, the flow in these bags is both water (containing algae) and air (the air "enriched" by the carbon dioxide in the exhaust gases from the flue of the generating plant). The channels appear to be fairly narrow, allowing for a slow flow, as well as being fairly transparent even with a healthy colony of algae growing inside.
Have a look at my video commenting on their publicity video at http://www.youtube.com/watch?v=bjFjE1RPKWg
While you are there you might want to also look at some of my other videos, including, Algae the Wonderfuel at
http://www.metacafe.com/channels/winfotech/
Sincerely,
Love
Stafford "Doc" Williamson
http://winfotech.com/energy/
