Getting methane from carbon dioxide at low cost

Keyword
CCS, carbon dioxide, recycling, methane
Information no
0426
Appeal point
Recycling of carbon dioxide in anaerobic environment
Suitable for combined use with carbon dioxide sequestration storage (CCS) and carbon dioxide injection-enhanced oil recovery method (CO2-EOR)
Summary
As a method of reducing carbon dioxide emissions, it has been proposed to recycle carbon dioxide by converting it into methane by a methanogen and reusing it as energy. The reaction of converting carbon dioxide to methane requires a certain amount of energy. The present invention is a method of generating hydrogen with a small amount of energy and converting carbon dioxide into methane at low cost, and has the following constitution.
1) A metal having a greater ionization tendency than hydrogen is placed in a mixed liquid of anaerobic water and liquid carbon dioxide.
2) Hydrogen is generated by oxidizing the arranged metal.
3) The generated hydrogen and the above mixed solution are supplied to a methanogen to convert carbon dioxide into methane.
These steps are configurations of the invented method for recycling carbon dioxide.
An example is shown in the figure. In the carbon dioxide recycling plant 100, the liquid carbon dioxide supplied to the mixer 11 via A is mixed with the anaerobic water supplied via B by the mixer to form a mixed liquid. The mixed liquid that has passed through the metal column 12 contains hydrogen generated by the redox reaction between the metal and the protons in the mixed liquid. In the methane production reactor 13, methane is produced by methanogens using carbon dioxide and hydrogen in the mixed solution as substrates. The produced methane is recovered via C and used as an energy source.
Schematic image
Application
Recycling of carbon dioxide, countermeasure against global warming
Relational patent
Item name
:
Carbon dioxide recycling method
Filing date
:
2013-06-03
Inventor(s)
Fumio Inagaki
Akira Ijiri