Table 4.
Fuel Characteristics of Commercial Wood Pellets and Coffee Waste-based Pellets

Type1	Moisture content(%)	Ash content(%)	Higher Heating value(MJ/Kg)	Bulk density(kg/m3)	Durability(%)
Larch pellet I2	8.7	0.5	18.6	789	98.0
Larch pellet II3	11.9	0.3	18.5	844	99.5
W : CW = 100 : 0	7.2	0.3	19.0	679	98.8
W : CW = 90 : 10	6.8	0.4	19.4	675	98.7
W : CW = 80 : 20	7.2	0.4	19.7	673	98.7
W : CW = 70 : 30	7.7	0.4	20.4	674	98.6
W : CW = 60 : 40	6.1	0.4	21.0	674	98.3
W : CW = 50 : 50	6.5	0.4	21.7	677	98.5
1st-grade pellet4	≦ 10	≦ 0.7	≧ 18.0	≧ 640	≧ 97.5
2nd-grade pellet4	≦ 10	≦ 1.5	≧ 18.0	≧ 600	≧ 97.5
3rd-grade pellet4	≦ 15	≦ 3.0	≧ 16.9	≧ 550	≧ 95.0
4th-grade pellet4	≦ 15	≦ 6.0	≧ 16.9	≧ 500	≧ 95.0

W and CW in the column mean larch sawdust and coffee waste, respectively.
It was obtained from SYENP Co. Ltd. (Cheongju, South Korea)
It was obtained form National Forestry Cooperative Federation (Yeoju, South Korea).
Minimum requirements of wood pellet standard designated by National Institute of Forest Science.