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The pyrolysis characteristics of GFRP (Glass Fiber Reinforced Plastic), which is a thermosetting plastic composed of glass fibers and polymer compounds, were determined under non-isothermal conditions while heating at 5–20 °C/min from 500 to 900 °C using a thermo-gravimetric analyzer (TGA) and a batch-type pyrolyzer. The kinetic parameters for the GFRP were derived from the Freedman method with resultant activation energy ranging from 41.4 kJ/mol to 78.4 kJ/mol. The main components of the product gases were carbon monoxide from the ether and carbonyl decomposition of polymer and hydrogen from the aromatic ring breakage. The structural variations in the GFRP char were determined using BET, SEM, and FT-IR techniques. The surface area of GFRP char exhibited its maximum value at 600 °C, decreasing at higher temperatures with the collapsing macro-pore structure. The decomposed portion of the polymers attached to the glass fiber increased when increasing the temperature from SEM image. These data are useful for understanding the GFRP pyrolysis and gasification processes. [ABSTRACT FROM AUTHOR]

Abstract: The BTL (biomass-to-liquid) process is an attractive process that produces liquid biofuels from biomass. The FT (Fisher–Tropsch) process is used to produce synfuels such as diesel and gasoline from gasified biomass. However, the H2S (hydrogen sulfide), COS (carbonyl sulfide) and CO2 (carbon dioxide) in the syngas that are produced from the biomass gasifiers cause a decrease of the conversion efficiency and deactivates the catalyst that is used in the FT process. To remove the acid gases, a pilot-scale methanol absorption tower producing diesel at a rate of 1 BPD (barrel per day) was developed, and the removal characteristics of the acid gases were determined. A total operation time of 500 h was achieved after several campaigns. The average syngas flow rate at the inlet of methanol absorption tower ranged from 300 to 800 L/min. The methanol absorption tower efficiently removed H2S from 30 ppmV to less than 1 ppmV and COS from 2 ppmV to less than 1 ppmV with a removal of CO2 from 20% to 5%. The outlet gas composition adhered to the guidelines for FT reactors. No remaining sulfurous components were found, and the tar component was analyzed in the spent methanol after long-term operations. [Copyright &y& Elsevier]

Abstract: 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 characteristics 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 0–0.4. 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. [Copyright &y& Elsevier]

Abstract: Recently, there has been a mounting interest in adopting non-premixed flames in order to improve flame stabilization in small combustors. This study introduces a non-premixed flame that was formulated in a narrow tube by an opposed injection of methane jet into a coaxial air stream. This configuration enhanced both the mixing and heat exchange between the burned and unburned gases. Various flame behaviors were observed and their stabilization limits were investigated for various fuel–air-flow rates and tube diameters. The temperature profiles near the flame and flue gas concentrations were measured. It was found that the flame stabilization limits were determined by three mechanisms depending on the flow rates and tube diameters: non-premixed flame quenching, flat flame stretch, and curved flame stretch. These results extend our understanding of the characteristics of non-premixed flames in a narrow space. [Copyright &y& Elsevier]

Hemodialysis (HD) has sufficient efficacy as a conventional diffusive treatment for removing small molecules, whereas hemofiltration (HF), which is a convective treatment, has an improved the clearance of intermediate-sized molecules. This paper reports a combined treatment (CT) which combines the diffusive and convective efficacies of HF several times weekly with HD weekly. CT modalities with various schedules and prescriptions are described mathematically using a variable-volume two-compartment kinetics model, and the kinetic parameters were obtained from previous clinical reports and a hemodialysis-related database. The blood concentration profiles of the three waste molecules for 52 weeks were calculated in order to compare the capability of removing small and intermediate-sized molecules to those of other renal treatments. The results by a computer simulation show that CT can reduce the frequency of sessions and the volume of replacement fluid compared with daily convective treatment, and achieve the adequate treatment efficiency with both small and intermediate-sized molecules for chronic renal failure patients. [Copyright &y& Elsevier]