Thermogravimetric analysis of the combustion of microalgae and microalgae blended with waste in N2/O2 and CO2/O2 atmospheres

The combustion of microalgae and municipal solid waste (MSW) under N2/O2 and CO2/O2 atmospheres was analyzed using a thermogravimetric instrument. The onset temperature of volatile release (Tv), maximum rate of weight loss (Rmax) and the temperature at the maximal peak (Tmax) were measured. As the blending ratio of microalgae was increased from 10% to 70% under N2/O2 atmosphere, Tv decreased from 269.4 to 247.4 °C, Tmax decreased from 310.8 to 288.0 °C, Rmax decreased from 11.94% to 7.88% and residual weight decreased from 30% to 20%. Thus, blending with microalgae can improve MSW combustion. The type of atmosphere did not affect Tv and Tmax, but replacement of N2 by CO2, resulted in the later appearance of the small humps (>600 °C) in the mass loss and rate of weight loss curves, burnout was less complete, and Rmax was lower, thus some improvement measures, such as an increase in oxygen concentration, are required under CO2/O2 atmosphere to achieve the same combustion performances in air.