Physicochemical Characterization and Kinetic Modeling Concerning Combustion of Waste Berry Pomace

Abstract

Herein waste biomass (blackberry pomace) was physicochemically characterized and its thermochemical products. This is coupled with the evaluation of the kinetic triplet (activation energy, pre-exponential constant and the rate of reaction) and thermal predictions for the combustion process for the first time via the AKTS thermokinetics package. The main kinetic modelling method employed was the differential iso-conversional analysis; however, the Flynn-Wall-Ozawa and ASTM E-698 methods were used as a comparison. The model was developed and validated from experimental DSC and TGA data; resulting in an excellent match (R 2 = 0.99544 and 0.99194, respectively). The activation energies were evaluated using the ASTM-E698 method (88.64 kJ.mol -1 ) and Ozawa-Flynn-Wall methods (50-140 kJ.mol -1 ). The differential iso-conversional method showed activation energy values were in the range of 84-197 kJ.mol -1 for the combustion of berry pomace. Isothermal predictions based on the model indicated at temperatures of 560 o C and 600 o C; the reaction had achieved 100% completion (=1) after 30 and 6 minutes, respectively. For the non-isothermal prediction, the heating rates of 50, 75 and 100 °C/min have a two-stage rate profile with a maximum peak in the first stage of the reaction. Thereafter, the reaction rate increases once again but not to the same effect as the first initial stage. For instance, at 100 °C/min, stage 1 and 2 are reported as 0.005381 and 0.005148 s -1 , respectively. Overall, this study demonstrates the success of the approach in modelling the thermochemical conversion of berry pomace as waste stream biomass.

Characterization and kinetic modeling for pyrolytic conversion of cotton stalks

“…The reason behind this shift has been explained by Osman et al, where a delay in decomposition may be attributed to a combined effect related to heat transfer and decomposition kinetics of the processed material. 11 By increasing the heating rate, the time required for the cotton stalks to reach a specific temperature is shortened, which may cause limitations in mass and heat transfer and lead to a delay in decomposition until a higher reaction temperature is achieved. Moreover, the possibility of a temperature gradient occurring may lead to the occurrence of various devolatilization stages.…”

“…7 The main model-free methods discussed in the literature include ASTM-E698, which is a model-free noniso-conversional approach, the Flynn-Wall and Ozawa (FWO), and Kissinger-Akahira-Sunrose (KAS), which are categorized as integral iso-conversional methods, and the Friedman method which is a differential iso-conversional method. [6][7][8][9][10][11][12][13] The main issue related to the ASTM-E698 method is that a single activation energy value is calculated, not considering reaction progress in such a complex thermochemical process. It is more suitable for a single-step reaction.…”

“…8 This software has been successfully utilized in several investigations and is recommended by the ICTAC kinetics committee as a highly applicable tool for calculating kinetic parameters. 8,9,11,29 Most importantly, the software can provide isothermal predictions, which is of great importance in analyzing kinetic behavior in continuous reactors operating under isothermal conditions, representing industrial-scale biochar production. This study aimed to characterize cotton stalk biomass, evaluate the kinetic triplet under pyrolytic conditions, and finally provide predictions on pyrolytic reaction progress of cotton stalks under various temperature profiles.…”

Industrial biochar systems for atmospheric carbon removal: a review

“…The process presented primary and secondary reactions, where independent reactions related to lignin, cellulose and hemicellulose occur simultaneously. Despite each of these components' independent behaviour, char, vapours and tar are produced (Osman et al 2020b). Figure 1 provides a depiction of the general pyrolysis mechanism of lignocellulosic material.…”

Комплексная Переработка Ягод Брусники И Клюквы

“…Следовательно, первоначальная обработка выжимок необходима для обеспечения удовлетворительного срока хранения. Обычно применяемые обработки включают сушку, а также измельчение и кондиционирование [19]. В данном исследовании использовалась обработка ультрафиолетом для предотвращения развития микробной активности.…”