Evaluation of synergy during co-pyrolysis of torrefied sawdust, coal and paraffin. A kinetic and thermodynamic dataset

Data in Brief 37 (2021) 107170 Contents lists available at ScienceDirect Data in Brief journal homepage: www.elsevier.com/locate/dib Data Article Evaluation of synergy during co-pyrolysis of torrefied sawdust, coal and paraffin. A kinetic and thermodynamic dataset L. Florentino-Madiedo, M.F. Vega, E. Díaz-Faes, C. Barriocanal ∗ Instituto de Ciencia y Tecnología del Carbono, INCAR-CSIC, Francisco Pintado Fe, 26, 33010 Oviedo. Spain a r t i c l e i n f o Article history: Received 19 March 2021 Revised 11 May 2021 Accepted 25 May 2021 Available online 27 May 2021 Keywords: Biomass Co-pyrolysis Synergy Kinetics a b s t r a c t This article aims to clarify and expand the information published in the article Evaluation of synergy during co-pyrolysis of torrefied sawdust, coal and paraffin. A kinetic and thermodynamic study , which evaluate kinetically and thermodynamically the existence of synergies during the co-pyrolysis of binary and ternary blends of coal, torrefied pine sawdust and paraffin. These materials were selected because they have been used before in the preparation of briquettes for the steel industry with good results. In order to facilitate the understanding and reproducibility of the main article, the following descriptions, dataset and figures have been provided: description and formulation of iso-conversional methods, some TGA curves and the standard deviation of the TG analysis, the activation energy of all the raw materials and their blends at different level of conversion using Friedman, Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods, as well as, the linear plots for their calculations for the KAS and FWO models; also the thermodynamic parameters for pyrolysis of all the samples studied and the theoretical and experimental plots for prediction of solid state reaction mechanism using Criado method of several weights of paraffin are include. DOI of original article: 10.1016/j.fuel.2021.120305 ∗Corresponding author. E-mail address: [email protected] (C. Barriocanal). https://doi.org/10.1016/j.dib.2021.107170 2352-3409/© 2021 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ) 2 L. Florentino-Madiedo, M.F. Vega and E. Díaz-Faes et al. / Data in Brief 37 (2021) 107170 ©2021 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ) Specifications Table Subject Environmental Science Specific subject area Environmental Engineering Type of data Tables and figures. How data were acquired Thermogravimetric analysis (TGA) was carried out in a TA Instruments SDT 2960 thermoanalyzer. Data format Raw Parameters for data collection Samples with a particle size of < 0.212 mm were used for each pyrolysis experiment. The samples were pyrolyzed from room temperature to 10 0 0 °C, at 3, 10, 20, and 40 °C/min. Nitrogen was used to maintain an inert atmosphere at a flow rate of 100 mL/min. Description of data collection Thermogravimetric analysis data were collected: mass loss and temperature. Data source location The thermogravimetric analysis data were collected at Instituto de Ciencia y Tecnología del Carbono, INCAR-CSIC, Oviedo, Asturias, Spain. https://data.mendeley.com/datasets/w22346frww/2 Data accessibility With the article Related research article L. Florentino-Madiedo, M.F. Vega, E. Díaz-Faes, C. Barriocanal, Evaluation of synergy during co-pyrolysis of torrefied sawdust, coal and paraffin. A kinetic and thermodynamic study, Fuel 292 (2021) 120305. https://doi.org/10.1016/j.fuel.2021.120305 [1] Value of the Data • Information on this data article deeply contributes to the understanding of thermochemical conversion processes. It described kinetically and thermodynamically the interactions of materials that have not been studied before. • Researchers in environmental engineering, material sciences, chemical, energy and related areas may benefit from the data presented in this work. • The data describe in deep how the initial mass and heating rate affect the paraffin thermochemical decomposition. In addition, data of kinetic and thermodynamic parameters of pyrolysis of coal, torrefied sawdust and paraffin, as well as their blends, at different level of conversion is presented here. • This data set will be beneficial for researchers who want to develop experiments with any of the material studied at this article or related materials. Also, these results contribute to the industry by describing new ways to reduce the energy required to carry out thermochemical conversion processes. 1. Data Description This article contains supplementary material for the paper Evaluation of synergy during copyrolysis of torrefied sawdust, coal and paraffin. A kinetic and thermodynamic study. Section 2, presents, in detail, the descriptions and formulation of the iso-conversional methods used. The TGA data of paraffin thermochemical decomposition is presented in Fig. 1 . Table 1 shows the values of maximum standard deviations of the experimental and calculated DTG curves. Figs. 2 and 3 shows the linear plots corresponding to the calculation of the activation energy (Ea) of the raw materials, using KAS and FWO methods. The linear plots of the blends studied, i.e. SPT/P, C/SPT, C/P and C/SPT/P, using KAS and FWO models, are presented in Figs. 4 and 5 . The linear plots calculated by Friedman model are presented at the main article. The Ea values at different L. Florentino-Madiedo, M.F. Vega and E. Díaz-Faes et al. / Data in Brief 37 (2021) 107170 3 Fig. 1. TGA analysis: (a) TGA curves of paraffin for different initial weights at heating rate 3 °C/min and (b) TGA curves of paraffin at different heating rates. Table 1 Values of maximum standard deviations of two replicas of the experimental DTG curves (DesMax-EXP/EXP) and of the experimental DTG curve and the calculated one (DesMax-EXP/CAL). Heating Rate Samples DesMax EXP/EXP DesMax EXP/CAL 3 °C/min C/SPT 0.10 0.07 C/P 0.16 0.16 C/SPT/P 0.14 0.15 SPT/P 0.19 1.20 10 °C/min C/SPT 0.42 0.51 C/P 1.13 0.63 C/SPT/P 0.43 0.42 SPT/P 0.67 2.79 20 °C/min C/SPT 1.58 1.58 C/P 0.84 0.82 C/SPT/P 0.42 1.21 SPT/P 0.94 4.29 40 °C/min C/SPT 1.38 0.87 C/P 1.28 2.10 C/SPT/P 1.19 2.28 SPT/P 2.63 13.89 4 L. Florentino-Madiedo, M.F. Vega and E. Díaz-Faes et al. / Data in Brief 37 (2021) 107170 Fig. 2. Linear plots for calculation of Ea using KAS method for: (a) Coal, (b) SPT and (c) Paraffin. L. Florentino-Madiedo, M.F. Vega and E. Díaz-Faes et al. / Data in Brief 37 (2021) 107170 5 Fig. 3. Linear plots for calculation of Ea using FWO method for: (a) Coal, (b) SPT and (c) Paraffin. 6 L. Florentino-Madiedo, M.F. Vega and E. Díaz-Faes et al. / Data in Brief 37 (2021) 107170 Fig. 4. Linear plots for calculation of Ea using KAS method for: (a) SPT/P, (b) C/P, (c) C/SPT and (d) C/SPT/P. L. Florentino-Madiedo, M.F. Vega and E. Díaz-Faes et al. / Data in Brief 37 (2021) 107170 7 Fig. 5. Linear plots for calculation of Ea using FWO method for: (a) SPT/P, (b) C/P, (c) C/SPT and (d) C/SPT/P. 8 L. Florentino-Madiedo, M.F. Vega and E. Díaz-Faes et al. / Data in Brief 37 (2021) 107170 level of conversion calculated from these linear plots are detailed at Tables 2 and 3 . Also, the frequency factor (A) values calculated with the Kissinger method from the Ea values are shown in Tables 2 and 3 . Thermodynamic parameters corresponding to the pyrolysis of individual components and their blends, using the apparent activation energy obtained from the Friedman method at a heating rate of 3 °C/min, are presented at Tables 4 and 5 , respectively. Finally, Fig. 6 shows theoretical and experimental plots for prediction of solid state reaction mechanism using Criado method (Z-master plot) of paraffin for different initial weights (1.8, 5 and 10 mg). Various files containing raw data obtained in a thermobalance from the thermal decomposition of the samples studied, using different heating rates and initial masses have been uploaded to Mendeley Data. Kinetic and thermodynamic parameters were obtained by applying isoconversional methods and Eyring equations. 2. Experimental Design, Materials and Methods Pine sawdust (Volatile matter = 79.4 wt% db and Ash = 0.3 wt% db) was obtained as waste from the timber industry and was torrefied at 300 °C in a rotary oven. The paraffin is a commercial product from Sigma Aldrich (VVW, CAS: 64742-51-4) and C is a bituminous coal (Volatile matter = 31.5 wt% db and Ash = 7.3 wt% db) normally used by the steel industry. The pyrolysis experiments were carried out in a TA Instruments SDT 2960 thermoanalyzer. Samples of around 10 mg with a particle size of < 0.212 mm were used for each pyrolysis experiment. The samples were pyrolyzed from room temperature to 10 0 0 °C, at 3, 10, 20, and 40 °C/min. Nitrogen with a purity higher than 99.9997% was used to maintain an inert atmosphere at a flow rate of 100 mL/min, α-alúmina was used as reference material in all tests. The thermobalance was calibrated using sample masses of 295.249 and 288.909 mg. The temperature was calibrated using the fusion temperature of Zn and Ag metals. In order to ensure repeatability, each experiment was repeated at least twice. The derivative of the weight loss curve (DTG curve) was calculated from the data obtained from thermogravimetric analysis (TG) as in Eq. (1) : DTG = 1 m i ·m ti +1 −m ti t i +1 −t i (1) The experimental mass loss and DTG curves were compared to the calculated profile by applying the additivity law, taking into account the composition of the blends as in Eq. (2) : Y cal = f 1 ·Y 1 + f 2 ·Y 2 (2) where, f 1 , f 2, and f 3 are the fractions of components 1 and 2 in the mixture, and Y 1 and Y 2, are the mass loss or the derivative of the mass loss with time (dm/dt) for components 1 and 2, respectively. The standard deviation associated to thermogravimetric analysis in the case of heating rate 3 °C/min was 0.005% for maximum DTG, 1.01 °C for Tmax and 0.42% for residue at 10 0 0 °C. 1. Descriptions and formulations of iso-conversional, Criado methods and thermodynamic study The general kinetic model that describes the degradation process during non-isothermal pyrolysis is expressed by Eq. (3) : dα dt = k ( T ) ·f ( α) (3) where αis the conversion, t is time, f( α) is a function that represents the reaction model and will depend on the reaction mechanism and k(T) is the reaction constant that depends on the temperature. Considering that the rate constant is a function of temperature and can be expressed by the Arrhenius law, Eq. (3) can be transformed into dα dt = A e −E a RT f ( α) (4) L. Florentino-Madiedo, M.F. Vega and E. Díaz-Faes et al. / Data in Brief 37 (2021) 107170 9 Table 2 The activation energy of coal, SPT and paraffin at different level of conversion using Friedman, KAS and FWO methods. Friedman method KAS method FWO method Conversion Tp ( °C) Ea (kJ/mol) R 2 A (s −1 ) Ea (kJ/mol) R 2 A (s −1 ) Ea (kJ/mol) R 2 A (s −1 ) Coal 0.1 445.12 216.41 0.9874 1.38E + 13 227.62 0.9858 9.50E + 13 216.41 0.9872 1.38E + 13 0.2 445.12 205.70 0.9873 2.19E + 12 214.87 0.9896 1.06E + 13 205.70 0.9907 2.19E + 12 0.3 445.12 215.76 0.9979 1.24E + 13 213.28 0.9915 8.06E + 12 215.76 0.9925 1.24E + 13 0.4 445.12 250.78 0.9948 5.05E + 15 222.68 0.9982 4.06E + 13 250.78 0.9984 5.05E + 15 0.5 445.12 269.56 0.9887 1.26E + 17 236.95 0.9995 4.71E + 14 269.56 0.9996 1.26E + 17 0.6 445.12 265.91 0.9968 6.75E + 16 249.35 0.9983 3.95E + 15 265.91 0.9985 6.75E + 16 0.7 445.12 326.70 0.9879 2.19E + 21 281.71 0.9921 1.01E + 18 326.70 0.9928 2.19E + 21 0.80 445.12 569.58 0.9755 1.76E + 39 505.81 0.9721 3.59E + 34 569.58 0.9736 1.76E + 39 Average a 290.05 269.03 290.05 SPT 0.1 348.33 199.99 0.9784 2.01E + 14 208.31 0.9694 1.05E + 15 206.83 0.9720 7.81E + 14 0.2 348.33 189.33 0.9994 2.41E + 13 190.47 0.9997 3.03E + 13 181.06 0.9997 4.66E + 12 0.3 348.33 190.50 0.9990 3.05E + 13 187.94 0.9991 1.83E + 13 188.38 0.9992 2.00E + 13 0.4 348.33 184.42 0.9987 9.10E + 12 187.50 0.9988 1.68E + 13 188.12 0.9989 1.90E + 13 0.5 348.33 185.70 0.9974 1.17E + 13 186.87 0.9990 1.48E + 13 187.67 0.9992 1.74E + 13 0.6 348.33 198.87 0.9914 1.61E + 14 187.76 0.9967 1.77E + 13 188.65 0.9971 2.11E + 13 0.7 404.50 213.61 0.9830 8.18E + 13 229.83 0.9622 1.57E + 15 228.88 0.9656 1.32E + 15 0.8 404.50 264.35 0.9896 8.25E + 17 252.07 0.9918 8.90E + 16 250.81 0.9925 7.08E + 16 Average a 203.35 203.84 202.55 Paraffin (1.8 mg) 0.1 255.01 81.49 0.9847 1.76E + 08 82.77 0.9896 1.46E + 08 87.27 0.9909 2.71E + 08 0.2 255.01 80.48 0.9896 5.09E + 08 80.85 0.9894 2.48E + 08 85.61 0.9911 4.77E + 08 0.3 255.01 80.80 0.9943 3.14E + 08 80.80 0.9916 3.19E + 08 85.74 0.9928 6.30E + 08 0.4 255.01 80.63 0.9907 4.33E + 08 81.19 0.9936 3.54E + 08 86.21 0.9944 7.21E + 08 0.5 255.01 79.79 0.9865 7.23E + 08 81.79 0.9937 4.31E + 08 86.21 0.9944 8.90E + 08 0.6 255.01 78.59 0.9836 1.40E + 09 79.34 0.9933 5.09E + 08 84.67 0.9940 1.07E + 09 0.7 255.01 79.10 0.9739 4.03E + 09 79.11 0.9912 7.90E + 08 84.58 0.9924 1.66E + 09 0.8 255.01 80.87 0.9771 1.14E + 10 79.49 0.9885 1.08E + 09 85.04 0.9901 2.31E + 09 Average a 80.22 80.67 85.67 Paraffin (5 mg) 0.1 260.12 216.41 0.9874 4.04E + 04 227.62 0.9858 2.30E + 06 216.41 0.9872 5.44E + 06 0.2 260.12 205.70 0.9873 2.35E + 04 214.87 0.9896 1.96E + 05 205.70 0.9907 5.57E + 05 0.3 260.12 215.76 0.9979 3.64E + 04 213.28 0.9915 9.97E + 04 215.76 0.9925 3.05E + 05 0.4 260.12 250.78 0.9948 9.63E + 03 222.68 0.9982 6.36E + 04 250.78 0.9984 2.05E + 05 0.5 260.12 269.56 0.9887 7.51E + 04 236.95 0.9995 5.84E + 04 269.56 0.9996 1.94E + 05 0.6 260.12 265.91 0.9968 4.41E + 04 249.35 0.9983 4.93E + 04 265.91 0.9985 1.69E + 05 0.7 260.12 326.70 0.9879 9.20E + 04 281.71 0.9921 4.61E + 04 326.70 0.9928 1.62E + 05 0.80 260.12 569.58 0.9755 3.74E + 05 505.81 0.9721 5.47E + 04 569.58 0.9736 1.96E + 05 Average a 290.05 269.03 290.05 Paraffin (10 mg) 0.1 280.43 81.49 0.9847 7.82E + 04 82.77 0.9896 1.05E + 05 87.27 0.9909 2.94E + 05 0.2 280.43 80.48 0.9896 6.21E + 04 80.85 0.9894 6.76E + 04 85.61 0.9911 2.01E + 05 0.3 280.43 80.80 0.9943 6.68E + 04 80.80 0.9916 6.68E + 04 85.74 0.9928 2.07E + 05 0.4 280.43 80.63 0.9907 6.42E + 04 81.19 0.9936 7.30E + 04 86.21 0.9944 2.31E + 05 0.5 280.43 79.79 0.9865 5.29E + 04 81.79 0.9937 8.38E + 04 86.21 0.9944 2.31E + 05 0.6 280.43 78.59 0.9836 4.02E + 04 79.34 0.9933 4.78E + 04 84.67 0.9940 1.62E + 05 0.7 280.43 79.10 0.9739 4.51E + 04 79.11 0.9912 4.52E + 04 84.58 0.9924 1.59E + 05 0.8 280.43 80.87 0.9771 6.78E + 04 79.49 0.9885 4.94E + 04 85.04 0.9901 1.76E + 05 Average a 80.22 80.67 85.67 a Only values with R 2 > 0.9 were considered to calculate the average value.