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Portable CO2 generation

  1. Jun 9, 2015 #1
    Does anyone know of a portable CO2 generation system capable of producing between 100-150 CFM 24/7/365? This system will be used off grid, and needs to be powered by either biofuel or electricity.

    Thank you.

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    Last edited by a moderator: Jun 9, 2015
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  3. Jun 10, 2015 #2

    berkeman

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    What'cha going to use the CO2 for? :smile:

    I Googled making CO2 and got lots of good hits. Have you tried that yet? Maybe you can find a technique that gives you other byproducts that you can use as well.
     
  4. Jun 10, 2015 #3
    Yes, several of my staff have scoured the web for sustainable CO2 generation options. Our application is unique requiring 100CF CO2 per hour 24/7/365 to supply our algae bioreactor. The remote off grid geographical locations make it exorbitantly expensive to resupply scheduled products or sub components. Also unknown events such as a hurricane, typhoon, or war demand that we are 100% sustainable. Thank you kindly for your suggestion.
     
  5. Jun 10, 2015 #4

    mfb

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    100 cubic feet per minute (post 1) or per hour (post 3)? That is a massive difference.
    At 1.6 kg/m^3, those 100 cubic feet have a mass of 4.4 kg, which requires burning about 1.6 kg of hydrocarbons. Assuming this is per hour, a modified car engine should be able to handle that, and produce useful mechanical energy at the same time. A car is not portable in the classical sense, but it can port itself. It will produce some other gases as well and you still have ~80% nitrogen, of course. Are other gases an issue?
     
  6. Jun 10, 2015 #5

    Borek

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    My first thought was about burning charcoal, but mfb's idea seems to be even better, as you can use the engine to produce electricity and make your installation independent.
     
  7. Jun 10, 2015 #6

    Ivan Seeking

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    I played with algae for a couple of years and concluded the same. At a minimum, about 40-50% of an algae-derived fuel is needed to run the generators for the farm [or bioreactors]. And the exhaust from that provides a ready supply of not only CO2, but by using a diesel engine, nitrogen, which represents a significant savings in the cost of production. In fact it might be possible to modify a diesel engine to provide 100% of the required nitrogen [beginning as NOx and then reacting it with water]. In principle it seemed that you should be able to recover the phosphorous and potassium as well. But we never addressed that possibility directly.

    Also, my working hypothesis was that the diesel engine acts as an air purifier [due to the high temps and pressures], which provides significant cost savings, as opposed to HEPA filters and the energy required to run an air supply system. Just the energy cost of the aeration system can be a killer! In a typical engine, you have about 3 psi to work with by removing the muffler, which is more than enough for the aeration.
     
    Last edited: Jun 10, 2015
  8. Jun 12, 2015 #7

    Ivan Seeking

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    Something else that occurred to me. You don't need CO2 24/7. You only need the CO2 while the algae is photosynthetically active - during the daylight hours.
     
  9. Jun 20, 2015 #8
    Our Bio reactor runs 24/7/365 requiring 100 CFM
     
  10. Jun 20, 2015 #9

    Ivan Seeking

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    You are using artificial lighting? If so, then to what advantage given the low conversion efficiency? You will only produce a fraction of the energy that it took to grow the algae.
     
  11. Jun 20, 2015 #10
    Our lighting specifically focused on stages of algal development optimizes wave length productivity while reducing heat signature throughout the growth cycle optimizing ATP1 & ATP2 and a 70% reduction in energy requirement.
     
  12. Jun 20, 2015 #11

    Q_Goest

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  13. Jun 20, 2015 #12

    Ivan Seeking

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    Are you trying to be profitable or is this purely for research purposes?

    Also, if you don't find the idea of using a diesel or IC engine as a CO2 source acceptable, could you explain why? It might help to provide context. Do you intend to make fuel e.g. biodiesel?
     
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