O-12 Hydrogen Production from Sewage Sludge without methane fermentation

Abstract

Amid the trend of global CO₂ reduction, effective use of hydrogen as a clean energy has attracted attention. In the present situation, however, hydrogen is produced by steam reforming of fossil fuels, mainly natural gas. Many researches are being conducted utilizing renewable resources such as biomass as its production method, but many problems still remain to obtain adequate results as a substitute for fossil fuels. We focused on sewage sludge with inevitable accumulation and low recycling rate and proposed a novel method of generating hydrogen directly with the aid of mixing treatment. In that process sewage sludge is mixed with calcium hydroxide and nickel hydroxide to produce hydrogen with relatively low temperature heating of about 600 degrees. By this method, a high hydrogen generation amount of 50 g per 1 kg of dried sewage sludge was obtained. However, in this method, since a large amount of calcium hydroxide and nickel hydroxide are used, it is a problem that a large amount of solid residue is generated and that the ratio of nickel hydroxide to the cost of hydrogen production is high It was. Therefore, in this study, it was confirmed that hydrogen is generated by recycling the solid residue after once generating hydrogen and reusing the solid residue.