Abstract
In this study, the co-combustion characteristics of coal and biomass blends (20, 40, 60, 80, and 100 wt%) were investigated by thermogravimetric analysis. All the samples were operated under an oxidative atmosphere, with a heating rate of 20 C/min. The reaction stages, ignition and burnout temperature, maximum weight loss rate, and different combustion indices were determined. When the percentage of biomass in the blends was increased, the maximum mass loss rate was enhanced in the second region, and the ignition and burnout temperature was lowered, indicating the higher reactivity and better combustion performance of the samples. The comprehensive performance index presented an N shape with the increasing biomass blending ratio. Based on various combustion indices, 20% was an optimum percentage for the co-utilization of coal-biomass blends. A significant promoting interaction was observed between corn straw and rice straw blends, while inhibiting effects occurred between rice husk and coal. The kinetic parameters of the blends were evaluated by the Coats and Redfern method using the nth-order reaction model. The value of activation energy and the pre-exponential factor increased with the decreasing biomass percentage in the blends.
Highlights
In recent years, the rapid economic development has caused increasing energy consumption, but the limited amount of nonrenewable energy resources and the depletion in the future pose a profound challenge to energy demand
The ignition temperature for coal, corn straw (CS), rice straw (RS), and rice husk (RH) was 401°C, 241°C, 256°C, and 270°C, respectively, and the burnout temperature for the four samples was 557°C, 486°C, 481°C, and 479°C, respectively. These results indicated that the biomass fuels had a much lower ignition temperature and were easier to achieve burnout due to the higher volatile content in biomass, resulting in better thermal reactivity
The destruction of the macromolecular structure and chemical bonds delayed the burnout of coal, and the reaction occurred at a higher temperature
Summary
The rapid economic development has caused increasing energy consumption, but the limited amount of nonrenewable energy resources and the depletion in the future pose a profound challenge to energy demand. The combustion of fossil fuels aggravates environmental pollution because of the emissions of nitrogen and sulfur pollutants as well as CO2. The utilization of renewable energy has attracted considerable critical attention. Among these renewable energies, biomass may play an essential role due to its advantages of fuel flexibility, high combustion efficiency, low pollutant emission, and carbon neutrality (Jayaraman et al, 2017). Co-combustion is considered the state-of-the-art technology to utilize biomass for replacing fossil fuels, such as coal, to meet the stationary energy demand. The co-combustion of coal and biomass blends would directly help to cut down the consumption of fossil fuels. The slagging and fouling problems of heating surfaces commonly faced in biomass combustion could be mitigated or eliminated through
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
