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Öğe Co-combustion of textile dyeing sludge with cattle manure: Assessment of thermal behavior, gaseous products, and ash characteristics(Elsevier Sci Ltd, 2020) Zhang, Junhui; Sun, Guang; Liu, Jingyong; Evrendilek, Fatih; Büyükada, MusaNot only can the incineration provide an effective waste stream reduction, but also it enhances the energy recovery. However, the combustion performance of textile dyeing sludge is poor due to its low combustible content and low calorific value. This study proposes to compensate for the defects by its co-combustion with cattle manure. The co-combustion exerted an inhibitive effect between 350 and 500 degrees C and a positive effect between 600 and 1100 degrees C on the thermal degradation. The strongest enhancement occurred with the blend ratio of 1:1. The co-combustion reduced the maximum SO2 emission and produced fewer gas species including CO2, CO, H2O, ketones, aldehydes, and low molecular weight chain-alkanes. The experimental and simulation results about mineral transformations showed that the blend ash consisted of SiO2, Fe2O3, CaMgSi2O6, NaAlSiO4, NaAlSi3O8, and Na2SO4. The blend ash had the lowest fusion temperature due to the formation of a low temperature eutectic. The findings provide insights into controls over gas emissions, energy recovery, and ash reutilization, essential to the development of cleaner and sustainable co-combustion systems. (C) 2020 Elsevier Ltd. All rights reserved.Öğe Co-pyrolytic mechanisms and products of textile dyeing sludge and durian shell in changing operational conditions(Elsevier Science Sa, 2021) Liu, Hui; Zhang, Junhui; Liu, Jingyong; Chen, Laiguo; Huang, Hongyi; Evrendilek, FatihTextile dyeing sludge (TDS) is a highly toxic solid waste whose co-pyrolysis can jointly achieve waste reduction and recovery of value-added products. This study aimed to fill the knowledge gaps about the co-pyrolysis mechanisms and products (gases and solids) and their dynamics in response to the atmosphere type, blend ratio, heating rate, temperature, and their interactions. The high temperature pyrolysis (>720 degrees C) in the CO2 atmosphere appeared as the best option for the waste reduction. The (co-)pyrolysis in the CO2 atmosphere enhanced S-containing air pollutants, CO, and CH4 but reduced NOx. The interaction effect between TDS and durian shell (DS) residues promoted the productions of furan and acid compounds and inhibited the productions of aromatic, phenolic, and N-containing compounds. The atmosphere type affected the type and strength of the reactions involved in the production of biochars. Our findings provide practical and new insights into the optimization of energy generation, product recovery, and emission control during the (co-)pyrolysis.Öğe Co-pyrolytic mechanisms, kinetics, emissions and products of biomass and sewage sludge in N-2, CO2 and mixed atmospheres(Elsevier Science Sa, 2020) Chen, Jiacong; Zhang, Junhui; Liu, Jingyong; He, Yao; Evrendilek, Fatih; Büyükada, Musa; Xie, WumingThe co-pyrolysis technology of the second-generation feedstocks has both engineering and environmental advantages towards resource recovery, waste stream reduction, and energy generation. However, there exists a large knowledge gap about the co-pyrolytic mechanisms, kinetics, emissions and products of biomass wastes. This study aimed to quantify the co-pyrolytic interactions between the five (N-2, CO2, and three mixed) atmospheres and the two feedstocks of sewage sludge (SS) and coffee grounds (CG) as well as their emissions and products. Thermogravimetric-Fourier transform infrared spectrometry, two-dimensional correlation spectroscopy and pyrolysis-gas chromatography/mass spectrometry analyses were combined. An eight-parallel distributed activation energy model was adopted to elucidate the dynamic reaction mechanisms in the co-pyrolytic atmospheres. The co-pyrolytic interaction changed the maximum weight loss rate of the first peak by -2.5 to 38.6% and -1.9 to 36.9% in the N-2 and CO2 atmospheres, respectively. The mass loss rate peak in the first stage was higher in the N-2 than CO2 and mixed atmospheres, while the peak temperature of the maximum mass loss rate in the second stage declined with the elevated CO2 concentration. The replacement of N-2 with the different CO2 concentrations significantly increased the activation energies of the 5th and 7th pseudo-components. The temperature dependency of evolved gases was of the following order: ethers/esters -> acids/ketones/aldehydes/CO2 -> hydrocarbons in the N-2 atmosphere, and acids/ketones/aldehydes -> esters/ethers -> hydrocarbons in the CO2 atmosphere. The co-pyrolysis improved the yields of the hydrocarbon and phenol-type compounds and reduced the formations of the acid and nitrogenous compounds. Our results yielded valuable insights into a cleaner co-pyrolysis process.Öğe Comparative (co-)pyrolytic performances and by-products of textile dyeing sludge and cattle manure: Deeper insights from Py-GC/MS, TG-FTIR, 2D-COS and PCA analyses(Elsevier, 2021) Zhang, Junhui; Zou, Huihuang; Liu, Jingyong; Evrendilek, Fatih; Xie, Wuming; He, Yao; Büyükada, MusaNot only does pyrolysis recover energy and value-added by-products but also reduces waste stream volume. The low volatiles and high ash contents of textile dyeing sludge (TDS) limit its mono-pyrolysis performance. This study aimed to conduct an in-depth analysis of its co-pyrolytic performance with cattle manure (CM). The co-pyrolysis enhanced the volatiles emission from the early devolatilization stage whose reaction mechanism shifted from a diffusion model to a reaction-order model. The further cracking of macromolecular materials was mainly elucidated by the reaction-order model. The temperature dependency of the co-pyrolytic gases was of the following order: aliphatic hydrocarbons > CO2 > alcohols, phenols, ethers, aldehydes, ketones, and carboxylic acids. The main co-pyrolytic volatile products were coumaran and 4-vinylguaiacol. The relative content of guaiacol-type components could be enhanced by co-pyrolysis and lowering the operational temperature to 450 degrees C. The interaction of co-pyrolysis enriched the char aromaticity. Our findings provide practical insights into the control and application opportunities and limitations on the high value-added energy and products from the co pyrolysis of TDS and CM.Öğe Coupled mechanisms of reaction kinetics, gas emissions, and ash mineral transformations during combustion of AlCl3-conditioned textile dyeing sludge(Elsevier, 2021) Zhang, Junhui; Chen, Jiacong; Liu, Jingyong; Xie, Wuming; Evrendilek, Fatih; Li, WeixinThough commonly used in the dewatering of textile dyeing sludge (TDS) before its incineration, chemical conditioning has yet to be evaluated in terms of its impact on the reaction mechanisms, emissions, and ash minerals. This study combined experiments and equilibrium simulations to disentangle the interaction mechanism among the combustion behaviors, gas emissions, ash minerals of TDS conditioned with(out) three blend ratios of the AlCl3 conditioner. The use of the AlCl3 conditioner slightly improved the performance of the combustion stage of volatiles and chars. No significant effect of AlCl3 conditioner was detected on the kinetic mechanism of its main combustion stage best elucidated by the nth-order and diffusion models. SO2 was the main evolved gas whose reduction between 600 and 800 degrees C was attributed to its increased retention rate by CaO from the decomposition of CaCO3. Aluminum compounds acted as a stimulator in SO2 emission between 800 and 1000 degrees C since the formation of calcium aluminosilicates. At above 1060 degrees C, CaSO4 decomposed rapidly, thus almost completely releasing inorganic S. This study supplies new insights into pollution 'controls on the combustion of TDS conditioned with Al salt coagulant.Öğe Fates of heavy metals, S, and P during co-combustion of textile dyeing sludge and cattle manure(Elseiver, 2023) Zhang, Junhui; Chen, Jiacong; Liu, Jingyong; Evrendilek, Fatih; Zhang, Gang; Chen, ZhibinThe co-combustion of textile dyeing sludge (TDS) and cattle manure (CM) may enhance circularity in terms of resource and pollution controls. However, the pollutant migrations and transformations of ashes and their characterization during the co-combustion are still unclear. This study aimed to quantify the transformation and migration behaviors of the co-combustion ashes, as well as the interactions involved via thermogravimetric experiments and thermodynamic simulations. The addition of TDS facilitated the conversions of Ni and Cr from the extractable form to the stable one, increasing their environmental safety. P dominated S for the reaction with Ca which promoted the generation of S-containing gas emission and apatite P. The reactions between the minerals in CM and Ca in TDS generated calcium silicate, decreasing the S-fixation ability of Ca, while increasing the emission of S-containing gases. Our findings provide insights into the interactions among the minerals, the heavy metals, and the specific elements and their impacts on pollutant emissions, thus enhancing pollution control strategies.Öğe Kinetics, thermodynamics, gas evolution and empirical optimization of cattle manure combustion in air and oxy-fuel atmospheres(Pergamon-Elsevier Science Ltd, 2019) Zhang, Junhui; Liu, Jingyong; Evrendilek, Fatih; Xie, Wuming; Kuo, Jiahong; Zhang, Xiaochun; Büyükada, MusaThermogravimetric (TG) and TG-Fourier transform infrared (FTIR) analyses were performed to quantify the comparative performances of cattle manure combustion in air (N-2/O-2) and oxy-fuel (CO2/O-2) atmospheres at four heating rates. Out of the distributed activation energy model, Flynn-Wall-Ozawa (FWO), Friedman and Starink methods (R-2 >= 0.86), the FWO method on average led to the highest R-2 value with the lowest activation energy. On average, the combustion in the oxy-fuel atmosphere had the lowest activation energy (180.6 kJ/mol) with the highest R-2 value (0.9812). Our TG-FTIR results showed that CO2 was the major gas evolution of the cattle manure combustion. Interaction effects of atmosphere type by heating rate on the multiple responses of remaining mass, derivative TG, and differential scanning calorimetry were found to be significant (p < 0.001). The joint optimization of the three responses was achieved at 424.6 degrees C in the air atmosphere at the heating rate of 40 K/min.Öğe Pyrolytic behaviors, kinetics, decomposition mechanisms, product distributions and joint optimization of Lentinus edodes stipe(Pergamon-Elsevier Science Ltd, 2020) Zou, Huihuang; Zhang, Junhui; Liu, Jingyong; Büyükada, Musa; Evrendilek, Fatih; Liang, GuanjieThe pyrolytic behaviors, kinetics, decomposition mechanisms and product distributions and joint optimization of Lentinus edodes stipe (LES) were quantified. Its main pyrolysis stages (the decomposition of hemicellulose) occurred between 200 and 400 degrees C. Random nucleation and nuclei growth (A(0.91)), and orders of reaction (F-1.6 and F-2.1) best explained the three sub-stages of the LES pyrolysis mechanism, respectively. The gas emissions were in good agreement with pyrolysis behavior. The main distributions of the pyrolytic products were classified into the 12 types of acids, alcohols, aldehydes, ketones, esters, phenols, glucopyranoside, aliphatic hydrocarbons, furans, aromatic hydrocarbons, N-heterocyclic substances, and N-containing substances. Cellobiose was found as pyrolytic product during 400 and 600 degrees C. For economic and practical reasons, the target functions of the four responses for the LES pyrolysis were jointly best optimized combining the temperature of 550 degrees C and the heating rate of 12.5 degrees C/min. This study offers theoretical and practical insights into the pyrolysis performance and products of LES or similar second-generation feedstocks in a thermal reactor.Öğe TG-FTIR and Py-GC/MS analyses of pyrolysis behaviors and products of cattle manure in CO2 and N-2 atmospheres: Kinetic, thermodynamic, and machine-learning models(Pergamon-Elsevier Science Ltd, 2019) Zhang, Junhui; Liu, Jingyong; Evrendilek, Fatih; Zhang, Xiaochun; Büyükada, MusaThe increased amounts of manure have become an issue of environmental management due to the rapid growth of livestock industry. This study quantified the pyrolytic performance and gaseous products of cattle manure using (derivative) thermogravimetric ((D)TG), Fourier transform infrared spectrometry (FTIR) and pyrolysis-gas chromatography and mass spectrometry (Py-GC/MS) analyses. The pyrolysis process of cattle manure was determined to occur in three stages, with the main reaction in the range of 161-600 degrees C. The N-2 atmosphere was found to be more favorable for the release of volatiles according to a higher comprehensive pyrolysis index in the range of 30 - 600 degrees C. The lower activation energies were shown to be required in the CO2 than N-2 atmosphere. Random forests algorithm outperformed multiple linear regression, gradient boosting machine, and artificial neural networks for the prediction of mass loss due to the cattle manure pyrolysis. The main gaseous products were CO2, phenol (23.23%), and furans (12.98%). The theoretical and practical guidance for the energy and resource utilization of cattle manure was provided by this study.Öğe Thermal conversion behaviors and products of spent mushroom substrate in CO2 and N-2 atmospheres: Kinetic, thermodynamic, TG and Py-GC/MS analyses(Elsevier, 2019) Huang, Jianli; Zhang, Junhui; Liu, Jingyong; Xie, Wuming; Kuo, Jiahong; Büyükada, Musa; Evrendilek, FatihThis study aims at characterizing pyrolysis/gasification behaviors and products of spent mushroom substrate (SMS) in the CO2 and N-2 atmospheres. The major decomposition stages occurred between 200 and 600 degrees C with the mass losses of 60.4 and 61.5% at 20 degrees C/min in the CO2 and N-2 atmospheres, respectively. The maximum mass loss rate grew with the increased heating rate, while DTG curves shifted toward a higher temperature. Volatiles were released easier in the N-2 than CO2 atmosphere with a higher comprehensive devolatilization index and decomposition rate. At above 750 degrees C, the char gasification in the CO2 atmosphere resulted in a significant mass loss as well as a less char yield. Average activation energies by the Flynn-Wall-Ozawa method were estimated at 212 and 214 kJ/mol in the CO2 and N-2 atmospheres, respectively. The higher thermodynamic parameters in the N-2 than CO2 atmosphere indicated the higher reactivity of the pyrolysis in the N-2 atmosphere. The reaction mechanisms of the volatiles decomposition were best described by g(alpha) = (1-alpha)(-1)-1 (R2 model) in the range of 200-370 degrees C in both atmospheres. The major pyrolysis products at 800 degrees C were identified using Py-GC/MS and composed mostly of aromatic compounds such as toluene and x-methyl-naphthalenes.Öğe Thermodynamic equilibrium simulations of thallium distributions in interactions with chlorine, sulfur, phosphorus, and minerals during sludge co-combustion(Springer, 2020) Liu, Jingyong; Zhang, Junhui; Sun, Guang; Büyükada, Musa; Evrendilek, Fatih; Dang, XiaoeEffects of interactions among chlorine (Cl), sulfur (S), phosphorus (P), and minerals on thallium (Tl) distributions were simulated using thermodynamic equilibrium conditions during the sludge co-combustion. Our results showed that Tl mainly existed in the forms of Tl2O3(s) and Tl(g) and did not react with SiO2, Al2O3, CaO, Fe2O3, and TiO2. Cl generated TlCl(g) and Tl(g) which in turn promoted Tl volatilization. S produced Tl2SO4(s), thus inhibiting Tl volatilization. P existence had no influence on Tl volatilization. With the couplings of Cl + S, S + P, and Cl + S + P, the reactions between single minerals and Tl were mainly controlled by S but P and Cl. With the Cl + P coupling, Cl controlled the reactions between the minerals and Tl, while P and the minerals had no significant impact. With the coupled minerals of SiO2 + CaO + Al2O3, S exerted a more influence than did Cl and P on the distributions of Tl, thus preventing Tl emissions.
