Comparison of Combustion and Pyrolysis Behavior of the Peanut Shells in Air and N2: Kinetics, Thermodynamics and Gas Emissions

Zhenghui Xu,Dongyao Chen,Haiwen Wu,Jianhang Huang,Xiang Xiao,Ping Fang,Lyumeng Ye,Zijun Tang

doi:10.3390/su12020464

Abstract

The influences of four heating rates on the combustion and pyrolysis behavior in the N2 and air atmosphere were investigated by the Fourier transform infrared spectrometry (FTIR) and thermogravimetric (TG) analysis. the distributed activation energy model (DEAM) and Flynn-Wall-Ozawa (FWO) were used to estimate Ea and A, ΔH, ΔG and ΔS. Experimental results showed that the similar thermal behavior emerged, but the temperatures in the air and N2 atmospheres representing the end of the reaction were about 500 °C and 550 °C, respectively. The results of FTIR showed the peak positions were basically the same, but the concentrations of aromatics, aldehydes and ketones produced by pyrolysis in the N2 atmosphere were higher. When the heating rate was 20 K/min, the comprehensive combustion parameters were 56.442 and 6.871 × 10−7%2/(min2• K3) in the air and N2 atmospheres, respectively, indicating that the peanut shells had great potential to become bioenergy.

Highlights

The intense change of global climate is associated with the increasing of the country’s consumption of fossil fuels
Based on its relatively low sulfur content (Table 1), the emissions of sulfur oxides produced by the peanut shells (PSH) during pyrolysis will be low, which reflected that the burning of the PSH seemed to be compatible with the environment
Compared to rice husks (0.10 and 0.84, respectively) [29], a relatively lower O/C ratio and the higher H/C ratio can be derived from the physicochemical properties of the peanut shell, so that the PSH were more suitable for burning than rice husks

Summary

Introduction

The intense change of global climate is associated with the increasing of the country’s consumption of fossil fuels. The limited availability of fossil fuels and their rate of consumption have led to the widespread development of alternatives to renewable energy. As a renewable and carbon dioxide neutral energy source, biomass fuels have received increasing attention in recent years [1,2]. It is reported that biofuels are a renewable energy source, and reduce carbon dioxide, nitrogen oxides, hydroxides and sulfur oxide emissions [3,4,5,6]. Biomass energy has become a replacement for 14% of global energy consumption. There have been various studies on biomass pyrolysis, focusing on waste mushroom matrix [7], straw [8], water hyacinth [9], tea residue [10], bagasse [3] and coffee grounds [11]

Objectives

Methods

Results

Conclusion