关键词: 生物质, 牦牛粪, 热重分析, 燃烧特性, 动力学

Abstract: In order to use yak dung more scientifically, the thermal cracking mechanism of yak dung biomass was investigated under different conditions to maximize the rational application of resources in high latitude regions. This paper aims to investigate the physicochemical properties and combustion characteristics of yak manure as a potential fuel energy. The physicochemical analysis results showed that the yak manure had a higher volatile matter and heating value. The combustion experiments were carried out using thermogravimetry analysis at different heating rates (10℃/min、20℃/min and 30℃/min), while the ignition temperature, burnout temperature and combustion characteristics index were calculated. Two kinetic models of KissingerAkahiraSunose (KAS) and OzawaFlynnWall (OFW) were applied to calculate the kinetic parameter. The basic characteristic analysis results showed that the biomass of yak dung had the characteristics of high volatility, low content of N and S elements and low content of pollutants in combustion products. The thermogravimetric test results showed that the lower heating rate was conducive to better heat transfer into the fuel, resulting in less combustion residue. While at the higher heating rate, the combustion characteristic index increased by nearly 25 times, leading to good combustion performance. The kinetic analysis results showed that the activation energy was mainly distributed between 50-95kJ/mol. The average activation energy calculated by the two methods was 70.97kJ/mol and 72.83kJ/mol respectively. Combining with the above results, this study can provide a theoretical basis and relevant data support for the further utilization of yak manure.

Key words: biomass, yak manure, thermogravimetry analysis, combustion characteristics, kinetic study