Cross-interaction of volatiles in fast co-pyrolysis of waste tyre and corn stover via TG-FTIR and rapid infrared heating techniques.

Using fast infrared heating technology to minimize the pyrolysis temperature differential and optimizing secondary reactions is advantageous for studying co-pyrolysis behaviors. In this study, the co-pyrolysis behaviors of waste tyres (WT) and corn stover (CS), including product distribution, pyrolysis kinetics, and thermodynamics, were studied using TGA-FTIR analysis and fast infrared heating reactor. The DTG curves for the co-pyrolysis of WT and CS significantly differed from the calculated values, implying that the pyrolysis intermediates produced by CS during the pyrolysis process may have synergetic effects with the pyrolysis of WT. The apparent activation energies using the Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods were similar, 244.88 kJ/mol and 245.93 kJ/mol, respectively. The experiment results suggest that the bio-oil yield increased first and then decreased with a further temperature increase. The yield of bio-oil gradually increased from 35.36% to 46.06% as temperature rose from 500 °C to 700 °C; but the further increasing to 800 °C decreased the bio-oil yield to 40.72%. The aromatic compounds in tar gradually increased with increasing the temperature, while the aliphatic compounds increased initially and then reduced. Meanwhile, the oxygenated compounds first decreased and then increased with increasing the pyrolysis temperature. The yield of light oil components (C＜10) increased from 5.11% at 400 °C to 7.71% at 700 °C. A further increase in the pyrolysis temperature to 800 °C reduced the light oil content to 4.93%.

Pyrolysis behaviors of anaerobic digestion residues in a fixed-bed reactor with rapid infrared heating.

Fast pyrolysis via rapid infrared heating may significantly enhance the heat transfer and suppress the secondary reaction of the volatiles. The effects of various pyrolysis temperatures on pyrolysis behaviors of anaerobic digestion residues (ADR) were studied in this research utilizing a fixed-bed reactor equipped with rapid infrared heating (IH), as well as to compare the pyrolysis products produced by rapid infrared heating (IH) to those produced by conventional electric heating (EH). Thermogravimetric (TG) analysis revealed that pyrolysis of ADR occurred in three decomposition stages. The results of pyrolysis experiments showed that increasing temperature first raised the bio-oil yield for IH and EH, peaking at 500-600 °C, but thereafter decreased the yield. In contrast to the findings achieved with EH, infrared heating (IH) presented a greater overall bio-oil yield but a lower gas yield. The bio-oil produced by IH increased from 8.35 wt.% at 400 °C to 12.56 wt.% at 500 °C before dropping to 11.22 wt.% at 700 °C. Gaseous products produced by IH have a higher heating value than those generated by EH. Nitrogenous compounds, ketones, and phenols make up the majority of the bio-oil. In the IH bio-oil, nitrogen compounds rose with increasing temperature, while those varied slightly in the EH bio-oil. The phenols content in IH bio-oil was much more than that of EH, exhibiting values of 8.63% and 2.95%, respectively. The findings of the FTIR spectra of biochar indicated that as the temperature increased, the chains of aliphatic side professedly reduced and the structure of biochar became considerably ordered for both heating techniques. The Raman spectra of IH biochar showed that the ratio of AG/AD rose progressively from 0.17 to 0.20 as pyrolysis temperature rose from 500 to 700 °C.

Fast pyrolysis characteristics and its mechanism of corn stover over iron oxide via quick infrared heating.

The harm done to the environment by fossil fuels was serious, and it is urgent to find effective methods and adopt carbon-neutral feedstock to prevent further environmental damage. An innovative infrared heating reactor was developed for the generation of high-yield bio-oil and cleaner pyrolysis gases. This work was devoted to exploring the fast pyrolysis characteristics and its mechanism of corn stover over the iron oxide in a novel infrared heating (IH) reactor and a traditional electric heating (EH) reactor. In the IH reactor, the bio-oil yield increased initially and then decreased with increasing pyrolysis temperature, reaching a maximum yield of 29 wt% at 600 °C. The yield of pyrolysis bio-oil and water decreased as the reusability number rose, whereas the char yield increased. Bio-oil yields decreased less from R0 to R3 and the catalyst was more effective in IH. IH produced more char and gas but considerably less water than EH, and its bio-oil had fewer phenols. Raman spectroscopy demonstrated that the aromatic structure of biochar increased as the pyrolysis temperature increased. Cellulose and hemicellulose can be completely cleaved at lower temperatures in IH. In addition, Fe2O3 catalysts have shown the advantages of low cost, efficient cycling, and long action time. Infrared heating coupled with iron oxide catalyst shows the potential to increase bio-oil yield and is more promising for industrial production than EH.