Ethanol is considered as a renewable transport fuels and demand is expected to grow. In this work, trends related to bio-ethanol production are described using Thailand as an example. Developments on high-temperature fermentation and membrane technologies are also explained. This study focuses on the application of membranes in ethanol recovery after fermentation. A preliminary simulation was performed to compare different process configurations to concentrate 10 wt% ethanol to 99.5 wt% using membranes. In addition to the significant energy reduction achieved by replacing azeotropic distillation with membrane dehydration, employing ethanol-selective membranes can further reduce energy demand. Silicalite membrane is a type of membrane showing one of the highest ethanol-selective permeation performances reported today. A silicalite membrane was applied to separate a bio-ethanol solution produced via high-temperature fermentation followed by a single distillation. The influence of contaminants in the bio-ethanol on the membrane properties and required further developments are also discussed.

Waste woody biomass samples including poly(vinyl chloride) (PVC), which were mixed with metal hydroxides as additives, were carbonized at 500 °C to investigate the catalytic effect of the additives on pyrolysis products and to elucidate the mechanism of biomass carbonization. The results showed that the yield of char significantly increased, whereas tar evolution was suppressed by the influence of metal hydroxides, even with the coexistence of PVC. Moreover, the interaction behaviors between the biomass structure including PVC and metal hydroxides were further investigated. It was clarified that the dehydration reaction to form a cross-linked structure in biomass by the effect of metal ion and the neutralization reaction between PVC and metal hydroxides were simultaneously occurred during the carbonization. The presence of chlorine component, which is one of corrosive substances, was confirmed in char structure by chlorine analysis. Therefore, a flushing method with warm and cold water was applied, to investigate the possibility of chlorine removal. The results showed that flushing with warm water and cold water are both effective for the removal of chlorine component in the char. Finally, the new pyrolysis process of NaOH-mixed waste biomass materials, including proposed heat recovery facilities, can be suggested as an effective system of biomass utilization for energy savings and CO 2 reduction.

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In this study, mass transfer of ash during bamboo powder combustion on a flat flame is investigated experimentally and numerically. The bamboo powder combustion consisted of volatiles emission, volatiles combustion, char formation, char combustion, and finally ash formation. The mass of ash formed was about 3 wt% that of raw bamboo powder. The mass of ash decreased with the equivalence ratio Φ for flat flame combustion.Part of the ash fused and then adhered to the Inconel mesh for wrapping of bamboo powder as bottom ash, flowing through the mesh. The mass adhered to the Inconel mesh depended strongly on the equivalence ratio Φ. The fusion tendency of the atmospheric oxidization ash agreed qualitatively with Liu's standard bamboo ash fusion test. On the other hand, as ash fusion started locally in this work, it suggests that the concentration of metal oxides of the atmospheric oxidization ash was not uniform. For the atmospheric oxidization ash at 600 °C, K2Si2O5, KAlSiO4, Na2CaP2O7, Mg2SiO4, K2SO4, and Fe2O3 were predicted to be the major eutectic materials. At 1120 °C, only Fe2O3 remained and the liquid components accounted for about 95%. On the other hand, the major eutectic materials for the combustion ashes of Φ = 0.85 and Φ = 1.0 at 1260 °C were MgO and Fe2O3, respectively. Therefore, the predicted eutectic materials of the combustion ash were changed appropriately in comparison with those for the atmospheric oxidization ash because of the fusion and disappearance of some metal oxide components during combustion.