Takeshi Sako
Shizuoka University,Japan
Title: Conversion of Waste Biomass to High-Calory Fuels Using High Pressure Water or Carbon Dioxide
Biography
Biography: Takeshi Sako
Abstract
Waste biomass are promising raw materials in 21st century because they are produced much and carbon neutral for use. Furthermore the proper treatment of them realizes the environment protection at the same time. We show two techniques to convert waste biomass to high-calory fuels using high pressure water or carbon dioxide.
(1) Production of powder fuel with hot water
Mixture of waste biomass and plastics is one of refractory wastes. Typical examples are municipal waste from houses and waste mixture from supermarkets and convenience stores. New technique was developed to convert the waste mixture to clean solid fuel with high heat of combustion. The waste mixture was treated in hot water at around 200 oC and 2 MPa for 30 min. We obtained the powder fuel with several mm in diameter. It had 25-30 MJ/kg in heat of combustion and no bad smell. It could be dehydrated easily and stored for more than a year.
(2) Extraction of bio-oil with CO2-expanded hexane
Expanded hexane with carbon dioxide (CO2-expanded hexane) was used to extract bio-oil from agricultural wastes such as rice bran and the performance was compared with those of pure hexane, supercritical carbon dioxide and liquefied carbon dioxide. CO2-expanded hexane had the maximum oil yield among them. Furthermore this extractant suppressed the phosphorus concentration in the extacted oil within 10 ppm, which causes the clogging of the fuel nozzle. As a result, CO2-expanded hexane could extract more amount of bio-oil with low phosphorus concentration under mild extraction condition.