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Water for Energy and Fuel Production
11.5.2 mAgmAlySiS
This process is another form of chemical method in which steam is injected on a
magma that is near the surface [11,143]. According to Northrup et al. [143], the following reaction would occur:
2
1 5
(11.53)
2FeO + H O → 2FeO . + H 2
Fresh basaltic lava contains on the order of 10 wt% ferrous oxide (FeO) and 1–2 wt%
ferric oxide (FeO 1.5 ). These components exist as dissolved constituents within the
melt and in the mineral suspended in the magma. Northrup et al. [143] calculated
hydrogen concentration, which resulted from equilibration of water with a solid
assemblage of hematite–magnetite for a total pressure of 100 MPa. The calculation
agreed well with the measured data.
As water accumulates in the basaltic lava, most of FeO is converted into FeO 1.5 ,
resulting in the drop of hydrogen production [144,145]. Northrup et al. [143] also estimated the hydrogen production at 1200°C. The estimates indicate that about 2.2 × 10 6
tons of hydrogen is potentially recoverable by water interacting with 1 km 3 of basalt
at high temperatures at 1000 MPa. The exact calculations of hydrogen production
rate requires the knowledge of available magma surface area and its cooling rate.
Northrup et al. [143] estimated that about 10 5 km 3 of magma bodies in areas of the
United States exist where hydrogen production by this method is possible.
11.5.3 rAdiolySiS
Radiolysis involves the injection of radioactive substances such as UO 2 (NO 3 ) 2 into
water which emits particles that have an energy in the region of 10 6 eV [11,142,149].
This energy will decompose some 10 5 water molecules per particle, and if there were
no recombination, significant amounts of hydrogen and oxygen would be generated.
When radioactive particles pass by water molecules, they strip a part of electron
shells so that protons are produced and the oxygen becomes cationic. The conversion efficiency is, however, low; between 1% and 5% of the radioactive energy is
translated in the productions of hydrogen and oxygen [141]. The efficiency can be
improved by the use of salts such as B 10 and Li 6 compounds. The process generates
hydrogen and oxygen in a mixture, which can be separated using a fuel cell where
hydrogen and oxygen are separated by anode and cathode, respectively.
The method can be valuable if the efficiency is improved to greater than 10%
and the radioactive material used is waste. Gomberg and Gordus [142] improved the
efficiency by using the nuclear fission either in a solid fuel configuration where the
radiation energy/heat ratio can be about 1/4 or in a fluid fuel configuration where all
the energy is available as radiation.
11.5.4 ShoCk WAveS And meChAniCAl PulSeS
Attempts to dissociate water using shock waves and mechanical pulses have also
been made [11]. The use of shock wave to dissociate diatomic molecules and organic
compounds has been successful [149]. It is possible to induce OH bond dissociation