• Energy Research

Glycerol which is a byproduct of biodiesel production is considered as a potential feedstock for syngas production with the increase of biodiesel demand. In this study, the charac- teristics of glycerol gasification under a microwave plasma torch with varying oxygen and steam supply conditions were investigated. The experimental results demonstrated that the gasification efficiency and syngas heating value increased with the supplied microwave power while the increase of oxygen and steam led to a lower gasification performance. In order to achieve high carbon conversion and cold gas efficiency in the microwave plasma gasification of glycerol, the O2/fuel ratio should be maintained at 0e0.4. It was revealed that the fuel droplet size and the mixing effect and retention time inside the plasma flames are critical factors that influence the product gas yield and gasification efficiency. This study verified that syngas with a high content of H2 and CO could be effectively produced from glycerol through microwave plasma gasification.

Glycerol which is a byproduct of biodiesel production is considered as a potential feedstock for syngas production with the increase of biodiesel demand. In this study, the charac- teristics of glycerol gasification under a microwave plasma torch with varying oxygen and steam supply conditions were investigated. The experimental results demonstrated that the gasification efficiency and syngas heating value increased with the supplied microwave power while the increase of oxygen and steam led to a lower gasification performance. In order to achieve high carbon conversion and cold gas efficiency in the microwave plasma gasification of glycerol, the O2/fuel ratio should be maintained at 0e0.4. It was revealed that the fuel droplet size and the mixing effect and retention time inside the plasma flames are critical factors that influence the product gas yield and gasification efficiency. This study verified that syngas with a high content of H2 and CO could be effectively produced from glycerol through microwave plasma gasification.

To investigate the kinetic characteristics of coking coal mixed with biomass during pyrolysis, thermogravimetric (TG) and thermo-balance reactor (TBR) analyses were conducted under non-isothermal and isothermal condition. Yellow poplar as a biomass (B) was mixed with weak coking coal (WC) and hard coking coal (HC), respectively. The calculated activation energies of WC/B blends were higher than those of HC/B blends under non-isothermal and isothermal conditions. The coal/biomass blends show increased reactivity and decreased activation energy with increasing biomass blend ratio, regardless of the coking properties of the coal. The different char structures of the WC/B and HC/B blends were analyzed by BET and SEM.

To investigate the kinetic characteristics of coking coal mixed with biomass during pyrolysis, thermogravimetric (TG) and thermo-balance reactor (TBR) analyses were conducted under non-isothermal and isothermal condition. Yellow poplar as a biomass (B) was mixed with weak coking coal (WC) and hard coking coal (HC), respectively. The calculated activation energies of WC/B blends were higher than those of HC/B blends under non-isothermal and isothermal conditions. The coal/biomass blends show increased reactivity and decreased activation energy with increasing biomass blend ratio, regardless of the coking properties of the coal. The different char structures of the WC/B and HC/B blends were analyzed by BET and SEM.

Abstract Technology for converting biomass such as rice husk into a useable energy sources are key to address energy consumption issues. The effects of temperature (600–900 °C), equivalence ratio (ER, 0.15–0.3), and addition of catalyst on the gasification characteristics of rice husk were investigated in a bubbling fluidized bed reactor with an inside diameter of 0.067 m and a height of 1.55 m. As the reaction temperature and ER were increased, the concentrations of CO and CO 2 in the product gas decreased. Slight increases in CH 4 and H 2 concentrations were also observed with increasing temperature. Throughout the temperature range of interest, an increase in ER resulted in decrement of both the higher heating value of the product gas and the cold gas efficiency. Furthermore, the effect of operating condition and addition of bed material were determined in a bubbling fluidized bed reactor. An increase in reaction temperature and ER decreased the tar content. The addition of calcined dolomite and olivine in the bed material reduced the amount of tar during rice husk gasification in a bubbling fluidized bed reactor. These results have the potential to be applied to the conversion of biomass into a useable energy source.

Abstract Technology for converting biomass such as rice husk into a useable energy sources are key to address energy consumption issues. The effects of temperature (600–900 °C), equivalence ratio (ER, 0.15–0.3), and addition of catalyst on the gasification characteristics of rice husk were investigated in a bubbling fluidized bed reactor with an inside diameter of 0.067 m and a height of 1.55 m. As the reaction temperature and ER were increased, the concentrations of CO and CO 2 in the product gas decreased. Slight increases in CH 4 and H 2 concentrations were also observed with increasing temperature. Throughout the temperature range of interest, an increase in ER resulted in decrement of both the higher heating value of the product gas and the cold gas efficiency. Furthermore, the effect of operating condition and addition of bed material were determined in a bubbling fluidized bed reactor. An increase in reaction temperature and ER decreased the tar content. The addition of calcined dolomite and olivine in the bed material reduced the amount of tar during rice husk gasification in a bubbling fluidized bed reactor. These results have the potential to be applied to the conversion of biomass into a useable energy source.

The catalytic oxidation of a model biomass tar, toluene, was studied using platinum and ruthenium on γ-alumina catalysts at various temperature, catalyst sizes, and metal contents in an environment with either the presence or absence of syngas. As the reaction temperature increased and the size of the catalyst decreased, the conversion of toluene increased. Usually, the higher content of platinum and ruthenium in the catalyst showed higher conversion of toluene. It was found that the presence or absence of syngas greatly affected the toluene conversion. The platinum catalyst showed a higher toluene conversion efficiency than the ruthenium catalyst at the same temperature in the absence of syngas, while in the presence of syngas, the ruthenium catalyst showed a better conversion efficiency than the platinum catalyst. The results indicate that a temperature of over 300 °C is required in order to oxidize tar efficiently using these catalysts.

The catalytic oxidation of a model biomass tar, toluene, was studied using platinum and ruthenium on γ-alumina catalysts at various temperature, catalyst sizes, and metal contents in an environment with either the presence or absence of syngas. As the reaction temperature increased and the size of the catalyst decreased, the conversion of toluene increased. Usually, the higher content of platinum and ruthenium in the catalyst showed higher conversion of toluene. It was found that the presence or absence of syngas greatly affected the toluene conversion. The platinum catalyst showed a higher toluene conversion efficiency than the ruthenium catalyst at the same temperature in the absence of syngas, while in the presence of syngas, the ruthenium catalyst showed a better conversion efficiency than the platinum catalyst. The results indicate that a temperature of over 300 °C is required in order to oxidize tar efficiently using these catalysts.

Abstract This study investigates air gasification properties of SRF with high content of residual mixed waste plastic in a 1 kg/h lab scale bubbling fluidized bed gasifier. Gasifier internal diameter is 0.114 m and its height is 1 m. Silica sand particles with a mean diameter of 400 μm is used as the bed material. During the gasification experiments the effect of bed temperature is determined in the range of 600–900 °C and the effect of air-to-fuel equivalence ratio (ER) is investigated in the range of 0.15–0.30. Gas analysis is conducted using a non-dispersive infrared analyzer and gas chromatograph. As the operating temperature and ER increases, the gas yield increases, and tar yield decreases. The yield of CO, CH4, H2, and C2H2 in the gas product increases with temperature, whereas those of CO2, C2–C3 hydrocarbons decreases. The increase in ER decreases the concentrations of CO, CH4, H2, and C2–C3 hydrocarbons and increases the CO2 in the gas product. H2/CO ratio substantially increases with rising temperature and decreases with rising ER. Carbon conversion efficiency (CCE) and cold gas efficiency reach peak at 800 °C and ER of 0.25.