Yazar "Evrendilek, Fatih" seçeneğine göre listele
Listeleniyor 1 - 20 / 172
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Arsenic partitioning behavior during sludge co-combustion: Thermodynamic equilibrium simulation(Springer, 2019) Liu, Jingyong; Xie, Candie; Xie, Wuming; Zhang, Xiaochun; Chang, KenLin; Büyükada, Musa; Kuo, Jiahong; Evrendilek, FatihUsing the computation method of thermodynamic equilibrium, effects of sewage sludge (SS) co-combustion conditions and interactions with Fe2O3, SiO2, CaO and Al2O3 on migration and transformation of arsenic (As) were simulated in oxy-fuel (CO2/O-2) and air (N-2/O-2) atmospheres. Arsenic mainly existed as As(s), As-4(g), As2O5(s), As4O6(g) and AsO(g) and volatilized more easily in reducing than oxidizing atmosphere. Increased O-2 concentration slowed down the formation rate of AsO(g), thus reducing the volatilization rate of As. With the increased pressure, the conversion rate of As2O5(s) into As4O6(g) accelerated. In the multi-chemical system of SiO2, Al2O3 and CaO, As reacted with CaO and Al2O3 to form AlAsO4(s) and Ca-3(AsO4)(2)(s) which inhibited As volatilization. SiO2 prevented As from reacting with CaO to generate Ca-3(AsO4)(2)(s). Fe2O3 affected reactions between Al2O3(CaO) and As which inhibited As volatilization. In the whole SS co-combustion system, As reacted with O-2 but had a weak affinity with Cl and with no arsenic chlorides observed.Öğe Ash-to-emission pollution controls on co-combustion of textile dyeing sludge and waste tea(Elseiver, 2021) Cai, Haiming; Liu, Jingyong; Kuo, Jiahong; Xie, Wuming; Evrendilek, Fatih; Zhang, GangGiven the globally increased waste stream of textile dyeing sludge (TDS), its co-combustion with agricultural residues appears as an environmentally and economically viable solution in a circular economy. This study aimed to quantify the migrations and chemical speciations of heavy metals in the bottom ashes and gas emissions of the co-combustion of TDS and waste tea (WT). The addition of WT increased the fixation rate of As from 66.70 to 83.33% and promoted the chemical speciation of As and Cd from the acid extractable state to the residue one. With the temperature rise to 1000 degrees C, the fixation rates of As, Cd, and Pb in the bottom ashes fell to 27.73, 8.38, and 15.40%, respectively. The chemical speciation perniciousness of Zn, Cu, Ni, Mn, Cr, Cd, and Pb declined with the increased temperature. The ash composition changed with the new appearances of NaAlSi3O8, CaFe2O4, NaFe(SO4)(2), and MgCrO4 at 1000 degrees C. The addition of WT increased CO2 and NOx but decreased SO2 emissions in the range of 680-1000 degrees C. ANN-based joint optimization indicated that the co-combustion emitted SO2 slightly less than did the TDS combustion. These results contribute to a better understanding of ash-to-emission pollution control for the co-combustion of TDS and WT. (C) 2021 Elsevier B.V. All rights reserved.Öğe Assessing CO2 sink/source strength of a degraded temperate peatland: atmospheric and hydrological drivers and responses to extreme events(Wiley, 2015) Evrendilek, FatihMonthly mean sink/source strength pattern of a degraded temperate peatland in northwestern Turkey was quantified using the eddy covariance technique between July 2010 and February 2014. Atmospheric and hydrological drivers and responses to extreme events of sink/source strength were analysed using multiple linear regression models, support vector machine, multilayer perceptron with principal component analysis and multiple comparisons following general linear models. On the basis of the three full-year measurements, mean annual, growing season and maximum estimates of net ecosystem CO2 exchange (NEE) were -0.22mg CO2 m(-2)s(-1), -0.28mg CO2 m(-2)s(-1) and -0.11mg CO2 m(-2)s(-1) in July, respectively. The main driver of changes in monthly mean NEE pattern was found to be latent heat flux. Independent validation results showed a similar predictive performance (r(2)=74%) of multiple linear regression and support vector machine models as a function of month, total rainfall, water table depth, relative humidity, latent heat, atmospheric water vapour, wind direction and downwelling shortwave radiation. A shift in NEE from a net sink to a net source was observed in response to the deepest and shallowest water table depths due to drought and flooding, respectively. Copyright (c) 2014 John Wiley & Sons, Ltd.Öğe Assessing monthly average solar radiation models: a comparative case study in Turkey(Springer, 2011) Sonmete, Mehmet H.; Ertekin, Can; Mengeş, Hakan O.; Hacıseferoğulları, Haydar; Evrendilek, FatihSolar radiation data are required by solar engineers, architects, agriculturists, and hydrologists for many applications such as solar heating, cooking, drying, and interior illumination of buildings. In order to achieve this, numerous empirical models have been developed all over the world to predict solar radiation. The main objective of this study is to examine and compare 147 solar radiation models available in the literature for the prediction of monthly solar radiation at Ankara (Turkey) based on selected statistical measures such as percentage error, mean percentage error, root mean square error, mean bias error, and correlation coefficient. Our results showed that Ball et al. (Agron J 96:391-397, 2004) model and Chen et al. (Energy Convers Manag 47:2859-2866, 2006) model performed best in the estimation of solar radiation on a horizontal surface for Ankara.Öğe Assessing neural networks with wavelet denoising and regression models in predicting diel dynamics of eddy covariance-measured latent and sensible heat fluxes and evapotranspiration(Springer London Ltd, 2014) Evrendilek, FatihEddy covariance (EC)-measured data were used to develop multiple nonlinear regression (MNLR) models of latent (LE) and sensible heat (H (s)) fluxes, and micrometeorological station-measured actual evapotranspiration (ET). Discrete wavelet transform (DWT) with symmlets (sym10), coiflets (coif10), and daubechies (db10) was used to decompose time series signals of LE, H (s), and ET into frequency components in order to feed denoised output data into 26 artificial neural networks (ANNs) with different learning algorithms, based on independent validation-derived values of coefficient of determination (r (2)), root mean square error (RMSE), mean absolute error (MAE), wavelet neural networks (WNNs) with coif10-1 and db10-1 outperformed ANNs, and MNLR models. The best ones out of 26 WNNs appeared to be multilayer perceptrons (MLPs) for LE and H (s), and time-delay network (TDNN) for ET, while the best ones out of 26 ANNs were determined as TDNN for LE, MLP for H (s), and generalized feedforward network (GFF) for ET. The combination of batch mode and Levenberg-Marquardt algorithm was adopted in the ANNs and WNNs more frequently and generated better accuracy metrics than the combinations of online mode and Momentum algorithm, and batch mode and Momentum algorithm.Öğe Assessing solar radiation models using multiple variables over Turkey(Springer, 2008) Evrendilek, Fatih; Ertekin, CanSolar radiation drives many environmental processes; however, needs to be estimated indirectly from more commonly measured meteorological variables since these data are not readily available from most climate stations. A geo-referenced dataset from 159 climate stations of 17 variables (maximum possible sunshine duration, mean, minimum and maximum air temperature, soil temperature, mean and maximum relative humidity, precipitation, cloudiness, evapotranspiration, extraterrestrial radiation, day length, declination angle, day of the year, latitude, longitude, and altitude) was used to model spatio-temporal dynamics of solar radiation over Turkey. A total of 78 empirical models of different mathematical functions with a different combination of 17 explanatory variables were compared based on the error statistics of the Jackknifing validation. The empirical models had adjusted coefficient of determination (R(adj)(2)) values of 22.7-96.5% based on the parameterization dataset (P < 0.05). Models 46 and 22.2 provided the most robust performance and were identified as generic models for the estimation of monthly changes in solar radiation over topographically complex terrain of the entire Turkey as a function of maximum possible sunshine hours, extraterrestrial solar radiation, mean temperature, and precipitation. The quadratic and cubic models performed best in terms of the error statistics (P > 0.05), while the performance of the hybrid models was worse than that of the linear, quadratic and cubic models in terms of maximum relative percentage error (e) (P < 0.01). In comparing the interpolation methods of inverse distance weighting and universal co-kriging, anisotropic spherical semi-variogram model of universal co-kriging was found to provide the best description of spatial autocorrelation and variability latent in these data based on the spatial leave-one-out cross-validation.Öğe Assessing thermal behaviors and kinetics of (co-)combustion of textile dyeing sludge and sugarcane bagasse(Pergamon-Elsevier Science Ltd, 2018) Xie, Wenhao; Huang, Jianli; Liu, Jingyong; Zhao, Yongjiu; Chang, Kenlin; Kuo, Jiahong; He, Yao; Büyükada, Musa; Evrendilek, FatihThermogravimetric and mass spectrometric (TG-MS) experiments were carried out using textile dyeing sludge (TDS), sugarcane bagasse (SB) and their blends with different ratios. (Co-)combustion kinetic parameters of each sample were calculate by using TG-derivative curves. CO2, NOx, NH3 and SO2 emissions were also quantified. The addition of SB to TDS lowered SO2 but enhanced NOx, NH3 and CO2 emissions. Calculated activation energies (E) of the pure TDS and SB, and their blend (TB64) according to the Flynn-Wall-Ozawa method were on average in the range of 185.6-253.9 kJ.mol(-1), 152.9-235.9 kJ.mol(-1) and 111.1-161.8 kJ.mol(-1), respectively. Based on the Kissinger-Akahira-Sunose method, E estimates of the pure TDS and SB, and the blend ranged from 183.1 to 251.0 kJ.mol(-1), 152.1 to 237.2 kJ.mol(-1) and 108.2 to 160.1 kJ.mol(-1), respectively. Our results indicated that the blend E was affected by the interactions between TDS and SB. (C) 2017 Elsevier Ltd. All rights reserved.Öğe Bioenergy and emission characterizations of catalytic combustion and pyrolysis of litchi peels via TG-FTIR-MS and Py-GC/MS(Pergamon-Elsevier Science Ltd, 2020) Liu, Chao; Liu, Jingyong; Evrendilek, Fatih; Xie, Wuming; Kuo, Jiahong; Büyükada, MusaThis study characterized the catalytic combustions and emissions of litchi peels as a function of five catalysts as well as the effect of the best catalyst on the pyrolysis by-products. Na2CO3 and K2CO3 accelerated the devolatilization but delayed the coke burnout, while Al2O3 enhanced the coke oxidation rate. Both comprehensive combustion index and average activation energy dropped with the added catalysts. CO2, CO, and H2O were the main combustion gases between 300 and 510 degrees C. CO2, C-H, C=O, and C-O were generated from the pyrolysis between 200 and 430 degrees C above which CO2 and CH4 were slightly released. Total H2O, CO2, CO, NOx and SOx emissions declined with the added catalysts among which K2CO3 performed better. The main pyrolytic by-products at 330 degrees C were terpenoids and steroids (71.87%), phenols (15.51%), aliphates (9.95%), and small molecules (2.78%). At 500 degrees C, terpenoids and steroids (78.35%), and small molecules (3.20%) rose, whereas phenols (12.87%), and aliphates (5.83%) fell. Fatty acid, and ester decreased, while terpenoids, and steroids increased with MgCO3 at 330 degrees C. Litchi peels appeared to be a promising biowaste, with MgCO3 as the optimal catalytic option in terms of the bioenergy performance, and emission reduction. (C) 2019 Elsevier Ltd. All rights reserved.Öğe Boosted decision tree classifications of land cover over Turkey integrating MODIS, climate and topographic data(Taylor & Francis Ltd, 2011) Evrendilek, Fatih; Gülbeyaz, ÖnderThis study investigates the impact of using different combinations of Moderate Resolution Imaging Spectroradiometer (MODIS) and ancillary datasets on overall and per-class classification accuracies for nine land cover types modified from the classification system of the International Geosphere Biosphere Programme (IGBP). Twelve land cover maps were generated for Turkey using boosted decision trees (BDTs) based on the stepwise addition of 14 explanatory variables derived from a time series of 16-day MODIS composites between 2000 and 2006 (Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI) and four spectral bands) and ancillary climate and topographic data (minimum and maximum air temperature, precipitation, potential evapotranspiration, aspect, elevation, distance to sea and slope) at 500-m resolution. Evaluation of the 12 BDTs indicated that the BDT built as a function of all the MODIS and climate variables, aspect and elevation produced the highest degree of overall classification accuracy (79.8%) and kappa statistic (0.76) followed by the BDTs that additionally included distance to sea (DtS), and both DtS and slope. Based on an independent validation dataset derived from a pre-existing national forest map and Landsat images of Turkey, the highest overall accuracy (64.7%) and kappa coefficient (0.58) among the 12 land cover maps was achieved by using MODIS-derived NDVI time series only, followed by NDVI and EVI time series combined; NDVI, EVI and four MODIS spectral bands; and the combination of all MODIS and climate data, aspect, elevation and distance to sea, respectively. The largest improvements in producer's accuracies were observed for grasslands (+50%), barrenlands (+46%) and mixed forests (+39%) and in user's accuracies for grasslands (+53%), shrublands (+30%) and mixed forests (+28%), in relation to the lowest producer's accuracy. The results of this study indicate that BDTs can increase the accuracy of land cover classifications at the national scale.Öğe Bottom slag-to-flue gas controls on S and Cl from co-combustion of textile dyeing sludge and waste biochar: Their interactions with temperature, atmosphere, and blend ratio(Elseiver, 2022) Huang, Hongyi; Liu, Jingyong; Evrendilek, Fatih; Zhang, Gang; Sun, Shuiyu; He, YaoS and Cl distribution patterns and their evolution pathways were quantified during the co-combustions of textile dyeing sludge (TDS) and waste biochar (BC). S in the flue gas rose from 10.60% at 700 degrees C to 45.09% at 1000 degrees C for the mono-combustion of TDS in the air atmosphere. At 1000 degrees C, S in the bottom slag and flue gas grew by 2.65% and fell by 2.11%, respectively, for the TDS mono-combustion in the 30%O2/70%CO2 atmosphere. The 40% BC addition increased the S retention in the bottom slag by 30.39% and decreased its release to the flue gas by 34.50% by changing the evolution of CaSO4 and enabling more K to fix S as K2SO4. The decomposition of inorganic Cl was the main source of the Cl-containing gases. The 20%O2/80%CO2 atmosphere (36.29%) and 40% BC addition (27.26%) had higher Cl in the bottom slag than did TDS mono-combusted at 1000 degrees C (25.60%) by inhibiting the decomposition of organic Cl. Our study provides insights into the co-combustion of TDS and BC and controls on S and Cl for a cleaner production. Future research remains to conducted to verify scale-up experiments.Öğe Catalytic combustion performances, kinetics, reaction mechanisms and gas emissions of Lentinus edodes(Elsevier Sci Ltd, 2020) Zou, Huihuang; Li, Weixin; Liu, Jingyong; Büyükada, Musa; Evrendilek, FatihThis study aimed to quantify the catalytic effects of CaO, Fe2O3, and their blend on the Lentinus edodes stipe (LES) and pileus (LEP) combustion performances, kinetics and emissions in bioenergy generation. Apparent activation energy (E-a) of LES and LEP increased with CaO, decreased with Fe2O3 and differed with their blend. The catalysts mainly affected the maximum intensity of volatiles combustion and partly the fixed carbon combustion. CaO, Fe2O3, and their blend decreased the release intensity of NO(x )from the LES combustion. Fe2O3 increased SO2 emission, while CaO, and the blend narrowed the emission temperature to the range of 200 to 450 degrees C. Kinetic triplets were estimated via the integral master-plots methods, and the best-fit reaction for the three sub-stages were obtained coupled with the model-free models. Our study provides a reference for the catalyzed biomass combustion in terms of pollution control, bioenergy generation, optimal design of incinerator, and industrial-scale application.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 Characterizing and optimizing (co-) pyrolysis as a function of different feedstocks, atmospheres, blend ratios, and heating rates(Elsevier Sci Ltd, 2019) Liu, Jingyong; Huang, Limao; Xie, Wuming; Kuo, Jiahong; Büyükada, Musa; Evrendilek, Fatih(Co-) pyrolysis behaviors were quantified using TG and Py-GC/MS analyses as a function of the two fuels of sewage sludge (SS) and water hyacinth (WH), five atmospheres, six blend ratios, and three heating rates. Copyrolysis performance, gaseous characterizations and optimization analyses were conducted. Relative to N-2 atmosphere, co-pyrolysis was inhibited at low temperatures in CO2 atmosphere, while the CO2 atmosphere at high temperatures promoted the vaporization of coke. The main (co-) pyrolysis products of SS and WH were benzene and its derivatives, as well as alkenes and heterocyclic compounds. Average apparent activation energy decreased gradually with the increased atmospheric CO2 concentration and was highest (377.5 kJ/mol) in N-2 atmosphere and lowest (184.7 kJ/mol) in CO2 atmosphere. Significant interaction effects on the mean responses of mass loss, derivative TG, and differential scanning calorimetry were found for fuel type by heating rate and atmosphere type by heating rate.Öğe (Co-)combustion behaviors and products of spent potlining and textile dyeing sludge(Elsevier Sci Ltd, 2019) Sun, Guang; Zhang, Gang; Liu, Jingyong; Xie, Wuming; Evrendilek, Fatih; Büyükada, MusaCo-combustion performances, ashes, gases and thermodynamics were quantified for spent potlining (SPL) and textile dyeing sludge (TDS) (with)out CaO. During the four decomposition stages of the blends according to the (D)TG experiments, the interaction among Na, Ca, F, Al, and S led to CaAl2O4, CaF2, and Na2SO4 which converted inorganic compounds into ash. Increased comprehensive combustion index, and decreased burnout temperature with 50% SPL indicated a better combustion and char burnout, and a shorter combustion process. CaO reduced the F volatilization and increased F- in the residual ash with 10% CaO. NaF was completely converted into CaF2 reducing the toxicity of soluble F- in the residual ash. The predom diagram of Na-Ca-F-S using thermal simulations showed the stable existence regions of CaF2 and Na2SO4. The changed migration mechanisms of F- and S caused ash compositions to consist of Na2SO4 and CaF2 for the co-combustions, and of NaF and CaSO4 for the mono-combustions. 10% CaO promoted CaF2, Na2SO4, CaAl2O4, and to a lesser extent, Fe2O3. The main gases evolved from the co-combustion included HF, SO2, COS, CS2, HCN, NH3, NO, and NO2. (C) 2019 Elsevier Ltd. All rights reserved.Öğe (Co-)combustion of additives, water hyacinth and sewage sludge: thermogravimetric, kinetic, gas and thermodynamic modeling analyses(Pergamon-Elsevier Science Ltd, 2018) Liu, Jingyong; Huang, Limao; Sun, Guang; Chen, Jiacong; Zhuang, Shengwei; Büyükada, Musa; Evrendilek, FatihAdditives and biomass were co-combusted with sewage sludge (SS) to promote SS incineration treatment and energy generation. (Co-)combustion characteristics of sewage sludge (SS), water hyacinth (WH), and 5% five additives (K2CO3, Na2CO3, Mg2CO3, MgO and Al2O3) were quantified and compared using thermogravimetric-mass spectrometric (TG-MS) and numerical analyses. The combustion performance of SS declined slightly with the additives which was demonstrated by the 0.03-to-0.25-fold decreases in comprehensive combustibility index (CCI). The co-combustion performed well given the 0.31-fold increase in CCI. Kinetic parameters were estimated using the Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS) methods. Apparent activation energy estimates by OFW and KAS were consistent. The addition of K2CO3 and MgCO3 decreased the weighted average activation energy of SS. Adding K2CO3 to the blend reduced CO2, NO2, SO2, HCN and NH3 emissions. CO2, NO2 and SO2 emissions were higher from WH than SS. Adding WH or K2CO3 to SS increased CO2, NO2 and SO2 but HCN and NH3 emissions. Based on both catalytic effects and evolved gases, K2CO3 was potentially an optimal option for the catalytic combustion among the tested additives. (C) 2018 Elsevier Ltd. All rights reserved.Öğe (Co-)pyrolytic performances and by-products of textile dyeing sludge and spent mushroom substrate(Elsevier Sci Ltd, 2020) Huang, Jianli; Liu, Jingyong; Chang, Kenlin; Büyükada, Musa; Evrendilek, FatihThe (co-)pyrolysis of textile dyeing sludge and spent mushroom substrate was conducted to characterize their thermal behaviors and by-products. The devolatilization of textile dyeing sludge mainly occurred between 150 and 500 degrees C, while the decomposition of inorganic matter as well as the secondary cracking of coke and tar happened between 500 and 1000 degrees C. The addition of spent mushroom substrate increased the release rate at the devolatilization stage of textile dyeing sludge and their blends due to its higher volatiles content. The enhanced co-pyrolysis performance occurred mainly at the high temperature. The melting of inorganic matter was enhanced with the temperature rise but weakened with the addition of spent mushroom substrate. Sulfur mainly existed as sulfate in textile dyeing sludge and as organic sulfur in spent mushroom substrate. With the temperature rise, nitrogen-containing compounds formed more stable compounds. Spent mushroom substrate promoted the formation of nitrogen oxides by converting nitrogen to an inactive form. Sulfates were decomposed at high temperatures partially turning into sulfide. 30% spent mushroom substrate increased the relative sulfate content at 800 degrees C and fixed sulfur into inorganic compounds. The relative contents of aromatics, and nitrogen-containing compounds rose in the bio-oils, whereas alkanes fell with the elevated temperature. Spent mushroom substrate enhanced the formation of aromatics and reduced the yields of nitrogen-containing compounds, and acidic volatiles. The co-pyrolysis appeared to improve the bio-oil quality and the pyrolytic performance of textile dyeing sludge. (C) 2020 Elsevier Ltd. All rights reserved.Öğe Co-circularity of spent coffee grounds and polyethylene via co-pyrolysis: Characteristics, kinetics, and products(Elsevier, 2023) Fu, Jiawei; Wu, Xijian; Liu, Jingyong; Evrendilek, Fatih; Chen, Tao; Xie, Wuming; Xu, Weijie; He, YaoSpent coffee grounds (CG) and polyethylene (PE) are the two typical types of major solid wastes. Their co-pyrolysis may be leveraged to reduce their waste streams and pollution and valorize energy and by-products. In this study, their co-pyrolysis performances, interaction effects, kinetics, and products were characterized in response to the varying temperature and blend ratio. The co-pyrolysis exhibited the two main stages of (1) the degradation of CG (180-380 degrees C) and (2) the depolymerization of PE and the decomposition of lignin (380-550 degrees C). The pyrolysis performance rose from 1.34x10(-4)%(3)center dot min(-2)center dot degrees C-3 with the mono-pyrolysis of CG to 26.32x10(-4)%(3)center dot min(-2)center dot degrees C-3 with the co-pyrolysis of 10 % CG and 90 % PE. The co-pyrolysis of 70 % CG and 30 % PE (CP73) achieved a lower activation energy than did the mono-pyrolysis of the two fuels. The products of the CG pyrolysis included a large number of alcohols, ethers, ketones, esters, and other oxygen-containing compounds, with a proportion as high as 65.01 %. The products of CP73 at 550 degrees C resulted in the yields of hydrocarbons and alcohols up to 93.61 %, beneficial to the further utilization of the co-pyrolytic products. Not only did the co-pyrolysis valorize its products, but also it enhanced their co-circularity. Artificial neural network-based joint optimization showed CP73 in the range of 517-1000 degrees C as the best combination of the conditions. The study provides new insights into the co-pyrolytic disposal of spent coffee grounds and polyethylene so as to improve the waste stream reduction and the valorization of energy and products.Öğe Co-combustion dynamics and products of textile dyeing sludge with waste rubber versus polyurethane tires of shared bikes(Elsevier Sci LTD, 2023) He, Yao; Chen, Xi; Tang, Xiaojie; Chen, Siqi; Evrendilek, Fatih; Chen, TaoThe co-combustions of major waste streams such as textile dyeing sludge (TDS) and waste tires of shared bikes may reduce the dependence on fossil fuels, as well as enhance their circular management and the recovery of their value-added products. In this study, the ash-to-gas products, interaction effects, and reaction mechanisms of the co-combustions of TDS and waste tires were characterized. The mono-combustions included the three stages of water evaporation, volatiles release, and mineral decomposition for TDS and the five stages for both rubber (RT) and polyurethane (PUT) tires. The three substages of the main stage of volatiles release for TDS had the activation energy of 124.5, 144.9, and 167.5 kJ/mol and were best explained by the reaction mechanism models of D3, D5, and F2, respectively. The (co-)combustion performance indices rose with the increased heating rate. The blend of 25% TDS with 75% RT (TR) and 75% PUT (TP) led to the best co-combustion performance according to comprehensive combustion index, with TP outperforming TR. The co-combustions of TP and TR reduced the activation energy required for the main devolatilization stage reaction. There was no significant difference in the main reaction mechanisms between the co-combustions. The interaction between TDS and waste tires reduced the applied energy required for the main devolatilization stage. The co-combustions at the low temperature produced O-H, CH4, CO2, CO, SO2, NO, carbonyl products, olefin products, and ketones. The cocombustions increased the production of C-H, reduced SO2 release and the viscosity of their ashes, promoted the complete combustion of substances, and alleviated the scale and sintering issues regardless of TP versus TR and caused the early release of NO from TP. According to the thermodynamic equilibrium simulations, the TR cocombustion promoted the retentions of Ca, S, Si, and Fe, in particular, the fixation of S. The addition of PUT enhanced the combination of Ca and Si into CaSiO3. The optimization based on the artificial neural networks pointed to the temperature range of 400-800 oC and the TR co-combustion as the optimal operational conditions.Öğe Co-combustion of sewage sludge and coffee grounds under increased O-2/CO2 atmospheres: Thermodynamic characteristics, kinetics and artificial neural network modeling(Elsevier Sci Ltd, 2018) Chen, Jiacong; Xie, Candie; Liu, Jingyong; He, Yao; Xie, Wuming; Zhang, Xiaochun; Chang, Kenlin; Büyükada, Musa; Evrendilek, Fatih(Co-)combustion characteristics of sewage sludge (SS), coffee grounds (CG) and their blends were quantified under increased O-2/CO2 atmosphere (21, 30, 40 and 60%) using a thermogravimetric analysis. Observed percentages of CG mass loss and its maximum were higher than those of SS. Under the same atmospheric O-2 concentration, both higher ignition and lower burnout temperatures occurred with the increased CG content. Results showed that ignition temperature and comprehensive combustion index for the blend of 60% SS-40% CG increased, whereas burnout temperature and co-combustion time decreased with the increased O-2 concentration. Artificial neural network was applied to predict mass loss percent as a function of gas mixing ratio, heating rate, and temperature, with a good agreement between the experimental and ANN-predicted values. Activation energy in response to the increased O-2 concentration was found to increase from 218.91 to 347.32 kJ.mol(-1) and from 218.34 to 340.08 kJ.mol(-1) according to the Kissinger-Akahira-Sunose and Flynn-Wall-Ozawa methods, respectively.
