An overview of torrefied bioresource briquettes: quality-influencing parameters, enhancement through torrefaction and applications

Bioresources and Bioprocessing

Table 7 Effect of torrefaction on the elemental constituents and the heating values of some agricultural wastes, and blends

Feedstock	Torrefaction temperature, retention time and device used	Elemental composition and heating value						Effect of torrefaction on the elemental composition and heating value
Feedstock	Torrefaction temperature, retention time and device used	C%	H%	O%	S%	N%	HV (MJ/kg)	C%	H%	O%	S%	N%	HV (MJ/kg)
^aGroundnut shell	300 °C/60 min, glass tube pyrolyzer	45.32	6.03	43.54		0.51	18.42	55.00	5.29	37.7	–	0.51	22.66
^aRice husk	300 °C/60 min, glass tube pyrolyzer	43.83	6.76	46.07	–	0.93	15.81	53.56	5.81	39.45	–	0.77	20.87
^bCoconut shell	300 °C/20 min, furnace	46.60	7.10	41.80	–	0.32	14.10	68.60	1.89	12.80	–	0.65	26.00
^cSugarcane bagasse	300 °C/90 min, furnace	47.30	6.56	45.54	–	0.60	19.45	78.60	6.46	14.56	–	0.38	33.45
^cCashew nutshells	300 °C/90 min, furnace	53.50	6.39	39.68	–	0.44	22.05	69.50	5.19	24.35	–	0.96	27.69
^dSoybean straw	350 °C, 45 min, tube furnace	44.30	5.80	45.20	0.10	0.70	16.70	58.70	4.10	26.50	0.10	1.10	21.10
^eLogging residue	300 °C, 30 min, electric furnace	51.59	6.52	40.96	0.11	0.83	21.19	54.48	5.32	39.01	0.04	1.15	22.03

C carbon content, H hydrogen content, O oxygen content, S sulphur content, N nitrogen content, HV heating value
^aGarba et al. (2017)
^bIbeto et al. (2016)
^cNunes et al. (2021)
^dZhang et al. (2020)
^eOhm et al. (2015)