Torrefaction of pine wood in a continuous system and optimization of torrefaction conditions

Keivani, Babak
Gultekin, Selin
Atımtay, Aysel
Red pine wood particles were torrefied in a screw conveyor reactor system continuously having a capacity of 5 kg/hour. During torrefaction, operating conditions were very important. Changes in the reactor temperature and the reactor residence times had large influences on product yields. With increasing torrefaction temperature, the volatile matter and oxygen content of biomass decreased, while fixed carbon content and heating value greatly increased. Design-Expert software package was used for the design of experiments (DOE) and to carry out the statistical analysis according to the experimental results. The optimum biocoal yield of 56.59%, energy yield of 47.49%, higher heating value of 26 761.9 kJ/kg, hardgrove grindability index of 91.76, H/C ratio of 0.099, and O/C ratio of 0.312 were obtained at 299.71 degrees C and 28.4 minutes (approximately 300 degrees C and 30 minutes). The biocoal prepared in this work exhibited similar properties to selected Turkish lignites. It suggests that the biocoal can be used as a supplementary fuel for production of energy in coal-fired combustion systems, especially as an auxiliary fuel for existing power plants.


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We have investigated the adsorption of RuSex (x =1-5) cluster on Se-doped graphene. The change of the adsorption energy with the number of Se atoms and magnetization values are investigated. Electronic properties of adsorption of RuSex (x =1-5) cluster on Se-doped graphene are investigated. The highest adsorption energy belongs to RuSe adsorbate. The biggest magnetization value belongs to RuSe2 adsorbate. This adsorbate makes the substrate half metallic. This property is important in electronic device appli...
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A novel reactor for pyrolysis of a polyethylene melt stirred by bubbles of flowing nitrogen gas at atmospheric pressure permits uniform-temperature depolymerization. Sweep-gas experiments at temperatures 370−410 °C allowed pyrolysis products to be collected separately as reactor residue (solidified polyethylene melt), condensed vapor, and uncondensed gas products. Molecular-weight distributions (MWDs) determined by gel permeation chromatography indicated that random scission and repolymerization (cross-link...
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Modelling, transient simulation and parametric study of parabolic trough collector with thermal energy storage
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In this thesis, a mathematical model of a parabolic trough collector field with a two-tank molten salt thermal energy storage is developed. The model is built in TRNSYS and by using MatLab, novel valve and thermal energy storage control algorithms are implemented. The model is sensitive to transient states inside the components and variations in weather and demand. Optimum parabolic trough collector length is determined for different insolation values to show the relation between direct normal insolation an...
Citation Formats
B. Keivani, S. Gultekin, H. OLGUN, and A. Atımtay, “Torrefaction of pine wood in a continuous system and optimization of torrefaction conditions,” INTERNATIONAL JOURNAL OF ENERGY RESEARCH, pp. 4597–4609, 2018, Accessed: 00, 2020. [Online]. Available: