Table 2.

Characteristics of studied solar dried SS and others used in thermochemical conversion studies according to literature.

	Ultimate analysis (%)
	Studied solar dried SS	Thipkhunthod et al., 2007	Tsai et al., 2009	Fonts et al., 2012	Chen et al., 2015
		Sewage sludge			Lignocellulosic biomass
C	48.21 ± 1	27.6–48.4	31.6–42.3	23.1–39.9	42.1–49.3
H	8.17 ± 0.3	6.5–7.4	4.9–6.3	3.8–5.9	5.5–6.1
O	10.15	35.3–53.7	31.8–35.6	18.8–23.5	44.2–50.9
N	1.71 ± 0.1	3.9–7.4	5.5–7.7	2.5–7.9	0.0–0.9
S	0.96 ± 0.1	1.2–7.6	0.6–1.4	0.8–1.0	0.1–0.8
	Proximate analysis (%)
Moisture content	9.49 ± 0,3	3.2–7.6	16.0–18.0	1.5–7.1	3.6–10.3
Ash content	30.80 ± 2	43.4–71.4	24.2–44.9	22.6–52.0	0.5–7.9
Volatile matter	58.81 ± 3	25.9–52.4	39.0–54.8	38.3–66.8	71.8–83.2
Fixed carbon	0.90	2.7–6.4	—	0.8–19.7	5.7–17.4
Hydrogen index∗	476	—	—	—	—
HHV (MJ/kg)	24.82	—	—	—	—

∗ in mg hydrocarbon/g organic carbon.