3.3.3. Combustion Characteristics

Table 8 presents the combustion characteristics of GG at different heating rates based on the TGA data and Equations (9)–(12). It is shown that the ignition and burnout temperatures rise with the increasing heating rate, while the corresponding time decreases. The combustion performance indices, *S*, *C*, *Di*, and *Db*, all increased with the heating rate. This highlights the fact that the combustion efficiency increases with the heating rate. This same trend has been observed in the published literature [8]. A correlation analysis was conducted using Pearson's coefficient, *r*, for the combustion atmosphere (*n* = 3). It was shown that the heating rate had a significantly positive correlation with the −*Rp* (*p* ≤ 0.03), *Rv* (*p* ≤ 0.0001), and *C* (*p* ≤ 0.03), whereas it showed no significant positive correlation with *Ti*, *Tb*, *S*, *Di*, and *Db* (*p* > 0.05). A similar finding, with the exception of comprehensive combustibility, *S*, was observed in the combustion study of tea leaves and waste teas [57]. The values of the indices obtained were of the same order of magnitude for nearly all the heating rates that were reported by Chen et al. [8] and Cai et al. [57]. In comparison with other lignocellulosic biomass in relation to their ignition temperatures at 10 ◦C/min (Pinus: 243 ◦C, 12 min [8]; Jackfruit peel: 213 ◦C, 18 min; Jackfruit seed: 246 ◦C, 21 min [39]; Tamarind husk: 240 ◦C, 21 min; Tamarind seed: 250 ◦C, 22 min [42]), the ignition temperature and time of the GG were higher. This implies that the ignition process for the GG may be relatively more difficult.


