Microbial World to Power Fuel Cells with Waste

According to the Nikkei Report, Sapporo Breweries Ltd. has developed bacterial degradation technology to turn food processing plant waste into hydrogen for fuel cells. Sapporo is testing its technology at a Hiroshima bread bakery, where unused dough is decomposed by microorganisms to generate hydrogen. "The system can generate 25,000 liters of hydrogen from 125 kg of dough, which otherwise would be thrown away. Combining this setup with a system for manufacturing would provide enough energy to meet the daily needs of five average households."

The article also reports the Kajima Corporation is developing a microbial fuel cell that generates electricity using a feedstock of sewage sludge.The Kajima fuel cell uses electrodes coated with microorganisms typically found in waste water and rice paddies. "These microbes release hydrogen as they metabolize the sludge, and this hydrogen reacts with oxygen to generate electricity." A prototype of the fuel cell can reportedly generate 130 watts of electricity per cubic meter."

(Cited from Industrial Biotech Innovation Report.)

Hydrogen from Biomass

Different process routes of hydrogen-production from biomass can be broadly classified as follows:

1. Thermochemical gasification coupled with water gas shift. Maximum conversion can be achieved. But significant gas conditioning is required and removal of tars is important.

2. Fast pyrolysis followed by reforming of carbohydrate fractions of bio-oil. It produces bio-oil which is the basis of several processes for development of fuels, chemicals and materials.But therr are chances of catalyst deactivation.

3. Direct solar gasification. Good hydrogen yield but requires effective collector plates

4. Miscellaneous novel gasification process.

5. Biomass-derived syn-gas conversion.

6. Supercritical conversion of biomass.Can process sewage sludge, which is difficult to gasify. Require a selection of supercritical medium

7. Microbial conversion of biomass.Waste water can also be treated simultaneously. Also
generates some useful secondary metabolites. Selection of suitable microorganisms is needed.