Formation of Incrustations during the Cocombustion of Biomass in Fluidised Bed Boilers

Table 3

The composition of power and desulphurisation component ashes, wt. %.

Raw material	Woodchip ashes	Woodchip ashes	Coal ashes	Limestone	Dolomite
Temperature	500°C	600°C	850°C	850°C	850°C
Oxide
Na2O	0.63	0.58	0.91	0.15	0.19
MgO	3.98	4.16	1.77	0.78	38.40
Al2O3	7.26	7.60	33.74	0.87	2.60
SiO2	32.32	39.47	43.30	2.17	2.33
P2O5	3.05	3.49	0.23	0.15	—
SO3	8.13	2.27	5.24	0.07	0.43
Cl	0.12	0.53	—	0.03	0.03
K2O	6.98	9.33	1.18	0.11	0.22
CaO	30.75	25.69	4.47	95.20	55.69
TiO2	0.64	0.67	2.01	0.06	0.02
V2O5	0.01	0.01	0.08	—	—
Cr2O3	0.01	0.01	0.03	—	—
MnO	1.91	2.47	0.06	0.03	—
Fe2O3	3.70	3.66	6.68	0.32	0.06
CuO	0.02	0.02	0.02	—	—
ZnO	0.15	0.14	0.02	—	—
Rb2O	0.02	0.02	—	—	—
SrO	0.09	0.07	0.06	0.06	0.02
ZrO2	0.02	0.03	0.06	—	—
BaO	0.22	0.24	0.06	—	—
NiO	0.02	0.01	—	—	—

: combustion temperature.