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In this study, co-pyrolysis experiments were carried out by blending coal slime (CS) and traditional Chinese medicine residue (CMR) in different proportions under nitrogen atmosphere using thermogravimetry-Fourier infrared spectroscopy-mass spectrometry (TG-FTIR-MS). Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) were used to calculate the activation energy (E) of samples with different conversion rates (α). The PCA method was used to analyze and compare the contribution of samples with different blending ratios to the principal components, and draw its score and load graph. A variety of artificial neural network models composed of different network topologies are selected to simulate and predict the remaining mass of the CS and CMR mixture pyrolysis, and the optimum model is obtained. [ABSTRACT FROM AUTHOR]

This work focused on the evaluation of co-combustion of sewage sludge (SS) and rice husk (RH) using thermogravimetric–Fourier transform infrared spectrometry method (TG–FTIR). The thermal behavior was assessed through the combustion characteristic, interaction, kinetics, and gaseous product characteristics. The (co-)combustion process was divided into three stages. Index D exponentially increased as RH blending ratio increased and index S also increased from 10 to 70% RH blending ratio, indicating that the combustion behavior was improved by the RH blending. The activation energy was evaluated by two model-free iso-conversional methods: Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS). The minimum value of average activation energy among blends was obtained at sample with 30% RH blending, which was 103.31 kJ/mol by FWO and 97.81 kJ/mol by KAS. Several typical gaseous products and functional groups were detected by FTIR spectrum. The results showed that CO2 was the main volatile and its yield increased with the RH blending ratio. [ABSTRACT FROM AUTHOR]

Scrap tire is a typical waste fuel, for which the combustion in the form of pellets is a feasible way. In this work, the ignition behavior, combustion process and pollutant emission of the scrap tire in pellet form are explored. The experiments were performed in the vertical heating tube furnace under different coflow conditions in CO2/O2 atmosphere. The temperature was set to 873, 973, 1073 K and the gas flow rate was set to 5, 10 and 20 L/min. The combustion images of scrap tire were recorded by the high-performance camera. The scrap tire pellet presented the characteristics of homogeneous ignition and the fly ash was captured around the scrap tire pellets. Increasing oxygen concentration and temperature shortened the ignition delay time and reduced the internal ignition temperature. The splash flame occurred during the volatile combustion under the conditions of high temperature, high oxygen concentration, and high gas flow rate. The distinct pores and cracks were found on the surface of char during the char combustion. The yields of pollutant gas increased as the gas flow rate increased from 5 to 20 L/min. With the increase of temperature, the emission of NO and SO2 was increased but NO2 emission was decreased. [ABSTRACT FROM AUTHOR]

Summary: To solve the problems of energy shortage and waste accumulation, the method of co‐combustion of sewage sludge (SS) and peanut shells (PS) was proposed. SS‐PS co‐combustion characteristics in air were investigated using artificial neural networks (ANN) and thermogravimetric analyses (TGA). The proportion of PS in the mixture was 10%‐50%. The temperature range of PS combustion (160‐560°C) is lower than that of PS combustion (170‐600°C). Activation energy was estimated from two non‐isothermal kinetic analysis methods: Kissinger‐Akahira‐Sunose (KAS) and Flynn‐Wall‐Ozawa (FWO). The kinetic mechanism of the combustion process was determined by using the master‐plots method. Multiple ANN models were established to predict TG data of SS‐PS co‐combustion. The best prediction model (ANN21) was obtained. The results showed a good overlap between the predicted and experimental TG data. The ANN model and the master‐plots method are the main innovations of this study. This study can promote the utilization and reduction of solid waste, and give guidance for the large‐scale application of SS‐PS co‐combustion. [ABSTRACT FROM AUTHOR]