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Öğe Catalytic combustions of two bamboo residues with sludge ash, CaO, and Fe2O3: Bioenergy, emission and ash deposition improvements(Elsevier Sci Ltd, 2020) Hu, Jinwen; Yan, Youping; Song, Yueyao; Liu, Jingyong; Evrendilek, Fatih; Büyükada, MusaThe catalytic combustions of bamboo leaves (BL) and branches (BB) with textile dyeing sludge ash (SA), Fe2O3, and CaO were qualitatively analyzed using thermogravimetric and Fourier transform infrared spectroscopy analyses, and thermodynamic equilibrium simulations. The catalysts (Fe2O3 > SA > CaO) exerted a more pronounced effect in the char combustion (third) stage and enhanced the volatiles and comprehensive combustion indices with 40 degrees C/min. The catalysts (CaO > SA > Fe2O3) reduced C- and N-containing gas emissions in the devolatilization (second) stage. CaO elevated the N-containing gas emission in the third stage, whereas Fe2O3 and SA inhibited the formation of NO precursors. BB presented a higher risk of slagging than did BL, while the improved empirical indices of the ash deposition pointed to CaO as the optimal catalyst. Our simulations showed the final ash components of BL and BB were mainly as SiO2 and K2Si4O9. The addition of CaO alone helped to form a high-melting point Ca-silicate. Although the addition of Fe2O3 had no effect on the ash conversion, SA reduced the formation of K-silicate in the ash. The catalysts (CaO > SA > Fe2O3) reduced the activation energy. Overall, the catalytic combustions improved the bioenergy and the N-containing gas emissions. SA as a Fe and Ca-rich industrial waste enhanced the combustion performance in terms of reductions in waste streams, gas emissions, and ash deposition. Our results supplied new insights into the efficient and clean bioenergy production of bamboo residues, and the waste utilization of SA. (C) 2020 Elsevier Ltd. All rights reserved.Öğe Catalytic effects of CaO, Al2O3, Fe2O3, and red mud on Pteris vittata combustion: Emission, kinetic and ash conversion patterns(Elsevier Sci Ltd, 2020) Song, Yueyao; Hu, Jinwen; Liu, Jingyong; Evrendilek, Fatih; Büyükada, MusaCatalytic effects of red mud (RM), calcium oxide (CaO), aluminum trioxide (Al2O3), and ferric oxide (Fe2O3) were quantified on the combustion, emission and ash characteristics of aboveground (PA) and belowground (PB) biomass of Pteris vittata using thermogravimetric, Fourier transform infrared, X-ray fluorescence and FactSage analyses. CaO affected the specific formation pathways of tar species and inhibited the CO2, HCN and SO2 emissions. Fe2O3 shortened the initial release time of the emissions. Al2O3 inhibited the final NO emission but did not control the N-containing products. RM catalyzed the combustion by suppressing the emissions. The enthalpy of PA was catalytically enhanced in the following order: CaO > RM > Fe2O3 > Al2O3. Only Fe2O3 increased the enthalpy of PB. The stationary index value of PB declined with the catalysts. The comprehensive combustion index of PA was high at 20 degrees C/min. Al2O3 reduced the risks of slagging, and fouling for PA and PB, while RM exerted a more pronounced effect on PA than PB. The fusion of low-melting point minerals accelerated the mass and heat transfers, and the ash melting. Activation energy was reduced by 275.99% with RM and by 119.82 and 115.81% with Al2O3, and Fe2O3 for PA, respectively. Our results pave the way for cleaner and sustainable production strategies with the catalytic biomass combustion. (C) 2019 Elsevier Ltd. All rights reserved.Öğe CO2-assisted co-pyrolysis of textile dyeing sludge and hyperaccumulator biomass: Dynamic and comparative analyses of evolved gases, bio-oils, biochars, and reaction mechanisms(Elsevier, 2020) Song, Yueyao; Hu, Jinwen; Liu, Jingyong; Evrendilek, Fatih; Büyükada, MusaThe CO2-activated co-pyrolysis technology presents promising potential to mitigate the environmental pollution and climate change. The dynamic analyses of evolved syngas, bio-oils, biochars, interaction effects, and reaction mechanisms of the co-pyrolysis of textile dyeing sludge (TDS) and Pteris vittata (PV) (hyperaccumulator biomass) were characterized and quantified comparatively in the three atmospheres. In the CO2-assisted atmosphere, the gasification of PV began to prevail between 600 and 900 degrees C, while in the N-2 atmosphere, PV and TDS were stable at 750 degrees C. The CO2-assisted co-pyrolysis reduced the apparent activation energy. The higher CO2 concentration during gasification led to the higher activation energy. The CO emission level of the CO2 and mixed atmospheres was almost 20 and 14 times that of the N-2 atmosphere, respectively. The CO release from the CO2 atmosphere was 1.4 times that from the mixed atmosphere. CO2 significantly changed the production pathway of biochar in the N-2 atmosphere, as was evidenced by the enhanced temperature sensitivity of O-C = O/hydroxy (- OH) in ester. Our findings research can provide new insights into the effectiveness of the CO2-assisted co-pyrolysis associated with reduced costs and hazardous wastes.Öğe Combustion behaviors of three bamboo residues: Gas emission, kinetic, reaction mechanism and optimization patterns(Elsevier Sci Ltd, 2019) Hu, Jinwen; Yan, Youping; Evrendilek, Fatih; Büyükada, Musa; Liu, JingyongThis study focused on the assessment of gas emissions and bioenergy potential of the combustions of bamboo leaves (BL), shoot leaves (BSL) and branches (BB) in the air atmosphere. The main combustion stage of the three residues occurred at between 200 and 600 degrees C, with three peaks of mass loss. The pattern of mass loss rate was BSL > BB > BL, with BSL having the best combustion characteristic parameters. The main evolved gases were CO2 and H2O at between 200 and 600 degrees C. Organic gaseous compounds were decomposed in the range of 200-400 degrees C. Air pollutants were produced in the range of 200-500 degrees C. N-containing gas pollutants were 0.01-0.1 times CO2, while SO2 was produced in a very small amount. BL produced more gas pollutants than did BSL and BB, while the controls over the gas pollutants should be more concentrated in the range of 200-400 degrees C. The joint optimizations of derivative thermogravimetry, differential scanning calorimetry, remaining mass, and conversion degree showed 653.2 degrees C and 5 degrees C/min as the optimum operational conditions for bioenergy utilization, while BB performed as the best feedstock. Among three iso-conversion methods used to estimate activation energy, Flynn-Wall-Ozawa led to best correlation. The Coats-Redfern method pointed to the second order reaction model (f (alpha) = (1-alpha)(2)) as the most likely reaction mechanism. Overall, the bamboo residues were promising as the environmentally friendly and renewable feedstock. Our findings can provide the basis for bioenergy generation, pollution control, and optimal efficiency when the industrial-scale combustions of the bamboo residues are adopted. (C) 2019 Elsevier Ltd. All rights reserved.Öğe Combustions of torrefaction-pretreated bamboo forest residues: Physicochemical properties, evolved gases, and kinetic mechanisms(Elsevier Sci Ltd, 2020) Hu, Jinwen; Song, Yueyao; Liu, Jingyong; Evrendilek, Fatih; Büyükada, Musa; Yan, Youping; Li, LeiUnlike light torrefaction at 200 degrees C (B200), the mild (250 degrees C) and severe (300 degrees C) torrefaction pretreatments (B250 and B300) significantly increased the calorific value, reduced the oxygen content and improved the surface morphology for bamboo residues (BR). The main oxygen-removing carriers of BR during torrefaction were CO2 and carbonyl compounds. Their torrefaction delayed the start and burnout temperatures of the BR combustions, increased CO2 emission and decreased NH3 and NO emissions significantly. The torrefaction reduced their activation energy in zone II (200-350 degrees C) and led to a transition from a nucleation to a diffusion mechanism. All the combustions in zone III (350-500 degrees C) were best explained by a reaction order model whose order rose with the elevated torrefaction temperature. Overall, BR appeared to be more suitable for the torrefaction at 250-300 degrees C. Our results can provide practical insights into how to turn BR into efficient and clean bioenergy.Öğe Dynamic insights into combustion drivers and responses of water hyacinth: Evolved gas and ash analyses(Elsevier Sci Ltd, 2020) Huang, Hongyi; Liu, Jingyong; Liu, Hui; Hu, Jinwen; Evrendilek, FatihNon-food biomass feedstocks owing to their advantages have come to the forefront as the efforts have been intensified to develop cleaner energy sources and technologies in the face of global climate change. This study aimed to dynamically characterize the combustion drivers and responses including the gas emission and ash deposition risks for roots (WHR) and stems and leaves (WHSL) of water hyacinth. Their combustion processes consisted of the four sequential stages of the water evaporation, the combustions of volatiles and fixed carbon, and the degradation of minerals. The WHR combustion had a higher total heat release (2140.6-4226.7 J/g) than did the WHSL combustion (1255.6-3110.6 J/g). In terms of the Flynn-Wall-Ozawa method, the average activation energy was estimated at 167.42 and 172.41 kJ/mol for WHR and WHSL, respectively. The reaction mechanisms of the volatiles and fixed carbon combustion stages were best elucidated by the F1 (f(alpha) = 1- a) and F3 (f(alpha) = (1- alpha)(3)) models for WHR and the F3 (f(alpha) = (1- alpha)(3)) and F1.5 (f(alpha) = (1- alpha)(1.5)) models for WHSL, respectively. CO2 was the main evolved gas for both WHR and WHSL and exhibited the fastest response to temperature. Evolved S-containing gases (SO2 and COS) (0.13% for WHR and 0.12% for WHSL) were extremely low. The WHSL ash had a higher risk of slagging and fouling than did the WHR ash. Our findings can provide insights into the cleaner and optimal production of the water hyacinth combustion. (C) 2020 Elsevier Ltd. All rights reserved.Öğe Performance and mechanism of bamboo residues pyrolysis: Gas emissions, by-products, and reaction kinetics(Elseiver, 2022) Zhang, Gang; Feng, Qiuyuan; Hu, Jinwen; Sun, Guang; Evrendilek, Fatih; Liu, Hui; Liu, JingyongThe performances and reaction kinetics of the bamboo shoot leaves (BSL) pyrolysis were characterized integrating thermogravimetry, Fourier transform infrared spectroscopy, and pyrolysis-gas chromatography/mass spectrometry analyses. The high volatiles and low ash, N, and S contents of BSL rendered its pyrolysis suitable for bio-oil generation. The main mass loss of BSL pyrolysis occurred in the devolatilization stage between 200 and 550 C. The peak temperatures of pseudo-hemicellulose, cellulose and lignin pyrolysis in BSL were 248.04, 322.65 and 383.51 C, respectively, while their average activation energies estimated by Starink method were 144.29,175.79 and 243.02 kJ/mol, respectively. The one-dimensional diffusion mechanism (f (alpha) = 1/(2 alpha)) best elucidated the hemicellulose reaction. The cellulose (f (alpha) = 0.74 (1 - alpha)[-ln (1 - alpha)]-13/37) and lignin (f (alpha) = 0.35 (1 - alpha)[-ln (1 - alpha)]-13/7) reactions were best described by the nucleation mechanisms. The estimated kinetic triplets accurately predicted the pyrolysis process. 619.3 C and 5 C/min were determined as the optimal pyrolytic temperature and heating rate. The C-containing gases were dominant among the non-condensable gases evolved from the pyrolysis. The NO(x )precursors (NH3 and HCN) were found more important than NO emission in pollution control. 2,3-dihydrobenzofuran, (1-methylcyclopropyl) methanol, heptanal, acetic acid, and furfurals were the main pyrolytic by-products. BSL-derived biochar is a relatively pure carbon-rich material with extremely low N and S content. The BSL pyrolysis yielded a promising performance, as well as value-added by-products to be utilized in the fields of bioenergy, fragrance, and pharmaceuticals.Öğe Reaction mechanisms and product patterns of Pteris vittata pyrolysis for cleaner energy(Pergamon-Elsevier Science Ltd, 2021) Song, Yueyao; Hu, Jinwen; Evrendilek, Fatih; Büyükada, Musa; Liang, Guanjie; Huang, Wenxiao; Liu, JingyongThe pyrolysis behaviors, kinetics, evolved products, and optimization of aboveground (PA) and below ground (PB) biomass of Pteris vittata were quantified. The pyrolysis performance in response to the elevated heating rate was improved by 21.21 and 16.79 times for PA and PB, respectively. CH4 and CO emissions were produced more from the pyrolysis of PB than PA. The increased pyrolysis temperatures of PA and PB led to the three consecutive releases of C=O (alcohol, ketone, acid, and furan), C-O (alcohol, phenol, and ether), and CO2, CH4, H2O, and CO. The formations of NH3 and HCN were more sensitive to the temperature rise with PB than PA. PA produced alcohol/ketone and acids by 1.81 and 1.32 times what PB produced. PB produced furan and carbohydrate/alkene by 1.56 and 2.52 times what PA produced. PA appeared as a more suitable feedstock than PB and showed an optimal pyrolysis behavior at 545 degrees C and 45 degrees C/min. Our findings can provide the basis for characterizing the process and environmental benignity of the hyperaccumulator pyrolysis. (c) 2020 Elsevier Ltd. All rights reserved.Öğe Synergistic effects, gaseous products, and evolutions of NOx, precursors during (co-)pyrolysis of textile dyeing sludge and bamboo residues(Elsevier, 2021) Hu, Jinwen; Song, Yueyao; Liu, Jingyong; Evrendilek, Fatih; Büyükada, Musa; Yan, YoupingThis study aimed to investigate the synergistic influences of the textile dyeing sludge (TDS) and bamboo residues (BR) co-pyrolysis, and its effects on the formation mechanisms of NH3 and HCN. The mass loss rate was lower for TDS than BR, with the co-pyrolysis with 50% BR exerting the strongest synergistic effect. The pyrolysis stages 1 (< 400 degrees C) and 2 (400 800 degrees C) were best described using the diffusion and third-order reaction mechanisms, respectively. Activation energy and frequency factor were lower for the pyrolysis of TDS than BR. The addition of no less than 50% BR significantly increased the emissions of CO2, CO, CH4, C=O, and C O and reduced the aromatic compounds. The thermal stability of N-A structure was lower in TDS than BR. The co-pyrolysis with 50% BR significantly inhibited the formations of NH3 and HCN and improved the aromaticity of biochar. This may due to the weakened hydrogenation reaction at N sites, the enhanced conversion of NH3, the inhibition of the ring cleavage in the char-secondary cracking, and the formation of more quaternary-N. Our results provide insights into the co-treatment of TDS and BR, and controls over NO,, precursors for a cleaner energy production.Öğe Torrefaction-assisted oxy-fuel co-combustion of textile dyeing sludge and bamboo residues toward enhancing emission-to-ash desulfurization in full waste circularity(Elsevier Science Ltd, 2022) Hu, Jinwen; Song, Yueyao; Liu, Jingyong; Evrendilek, Fatih; Zhang, GangEmission-to-ash desulfurization and full waste circularity can be enhanced by the proper selection of multiple wastes and operational conditions. In this context, a new combination of textile dyeing sludge (TDS), bamboo residues (BR), torrefaction, and oxy-fuel (O-2/CO2) atmosphere was proposed in this study. Their blend (0.5TDS) torrefied at 250 degrees C (T250) improved its co-combustion performance by 17.30% based on the comprehensive combustion index (CCI). The CCI value of T250 in the oxy-fuel atmosphere of 20% O-2/80% CO2 was about 3.6 times that of the mono-combustion of TDS in the air atmosphere. The co-combustion interaction reduced SO2 emission since the increased alkali metals and alkaline earth metals (especially K) preferentially reacted with S to form sulfate at <= 700 degrees C. Compared to the air mono-combustion of TDS, T250 in 20% O-2/80% CO2 reduced SO2 emission (mg/MJ) by 55.09%. With the temperature rise from 700 to 900 ?, K-sulfate was completely transformed into aluminosilicate and released the captured SO2 in which case Ca became the main S-fixing agent. The shift from air to 20% O-2/80% CO2 retained sulfate in the bottom ash. Our findings provide new and practical insights into sustainable, efficient, and clean co-combustion and energy utilization.
