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Maximum productivity of PBR

PostPosted: Thu Jan 29, 2009 6:30 am
by cacofonix
Typicall,y, in pond systems, you get a microalgal growth density of about 1g/l. If you are lucky 2 g /l. In PBR, I read that people are getting about 5-8 g /l. Which is an impressive 3-5 fold increase from open ponds (well, PBRs cost 10 times more than open ponds, capex, so I guess that sort of balances out :-( )

Does anyone know what is the maximum productivity possible in PBRs? Is it possible to get (at least theoretically) something like 20 g /l ? If PBRs are the way to go, some one got to find out a dramatic reduction in capital costs / unit yield...

Re: Maximum productivity of PBR

PostPosted: Wed Feb 04, 2009 11:04 am
by guru
Microalgae grows with a density of about 0.1 % in water whereas in controlled condition the density will be high around 0.6%.
That will be 6 g of algae per litre of water. 20g/l .. For that you might need to consider improving the factors like Efficiancy of light transmission, Efficiency of convertion of incident light to biomass, Microalgae production rate.....

An intresting article titled “Algae ripoff - Photobioreactors with outrageous claims” - http://biodieselfever.com/?p=4

hope it ll be useful for you.

Cheers,
Guru

Re: Maximum productivity of PBR

PostPosted: Mon Feb 09, 2009 8:54 pm
by cacofonix
Guru,

Thanks for your reply

That's about 6 times the amount you get in open ponds - that was the number I had been reading elsewhere as well.

So that is impressive - a six fold increase on an already high yield. If only the photobioreactors were less costly!