Shuaihua Guo

Continued social and mobility development has caused a sharp increase in the number of waste tires, increased environmental pollution, and waste of limited resources. Agricultural residues as a bioresource, which has drawn increased attention in recent years. The thermochemical conversion of waste tires and agricultural residues and their mixtures offers important prospects for scientific development, which can provide energy security and a much reduced environmental footprint. In this paper, pyrolysis of waste tires and its co-pyrolysis with maize stalk, wheat straw, cotton stalk, rape straw, or peanut shell agricultural residues, in mass ratios of 1:1 were investigated at different heating rate using thermogravimetric analysis. The kinetic parameters were calculated using Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS) kinetic models at heating rates of 20, 30, and 50 °C/min. The synergistic effect between waste tires and agricultural residues was explored by calculating the deviation between the experimental and calculated values. The results showed the presence of a synergistic effect between the co-pyrolysis of waste tires and the residual agricultural residues. In the kinetic analysis, activation energies of waste tires, agricultural residues, and their mixtures were calculated using the two models. The reaction followed a multistage reaction mechanism. The differential thermogravimetry behavior of the mixture was similar to the weighted aggregate results of the waste tire and agricultural waste samples, pyrolyzed separately. These results provide some insights into the combined treatment of waste tires and agricultural waste residues.

The co-thermal chemical conversion of biomass and waste tires is an important direction for the utilization of waste resources to produce renewable energy. In this study, the product distribution and synergistic effects during the co-pyrolysis of agricultural residues and waste tire were analyzed by a pyrolyzer coupled with a gas chromatograph/mass spectrometer (Py-GC/MS). Pyrolysis and co-pyrolysis products were analyzed at 550 °C and 650 °C for maize stalk (MS), wheat straw (WS), waste tire (WT) feedstocks, as well as mixtures of wheat straw-waste tire (WS:WT mass ratio of 1:1), and maize stalk-waste tire (MS:WT mass ratio of 1:1). The results showed that the co-pyrolysis of agricultural residues and waste tire promoted the release of phenols, aldehydes, and ketone derivatives, and reduced the formation of H2 and H2O. In addition, a relatively high content of aromatic hydrocarbons was obtained at 650 °C temperature, while 550 °C was optimal when considering the formation of ketones. The results showed a synergistic effect in the co-pyrolysis of biomass and waste tire.