Effect of minerals on semi-coke combustion characteristics of maceral with different reducibility

doi:10.11949/0438-1157.20190205

Abstract

Abstract:

The effects of intrinsic minerals and three inorganic components (CaO, Fe₂O₃ and Al₂O₃) on the semi-coke combustion reactivity of maceral with different reducibility were investigated on a thermogravimetric analyzer. The results indicated that the combustion reactivity of maceral chars from the weakly reductive coal is better than that from the reductive coal. The inherent mineral matter of vitrinite reduces the ignition temperature of vitrinite chars, while the inherent mineral matter of inertinite shows obvious inhibition effect on their chars combustion reaction. Three added mineral matter inhibit the combustion reaction of maceral chars from the reductive coal, and the relative inhibiton sequence could be described as follows: Al₂O₃>CaO>Fe₂O₃, while CaO has a little catalytic effect on the combustion reaction of maceral chars from the weakly reductive coal, and the inhibition effect of Al₂O₃ and Fe₂O₃ on the combustion reaction of maceral chars from the weakly reductive coals is lower than that on the combustion reaction of maceral chars from the reductive coal.

Key words: maceral, reducibility, pyrolysis, coal combustion, reactivity, mineral matter

摘要：

在热重分析仪上考察了内在矿物质和三种无机组分（CaO、Fe₂O₃和Al₂O₃）对不同还原程度煤显微组分半焦燃烧反应性的影响。结果表明，弱还原性煤显微组分半焦的燃烧反应性高于还原性煤显微组分半焦；内在矿物质降低了镜质组半焦的起燃温度，但对惰质组半焦燃烧有明显抑制作用；三种外加矿物质对还原性煤显微组分半焦燃烧均有抑制作用，抑制顺序为Al₂O₃>CaO>Fe₂O₃，而CaO对弱还原性煤显微组分半焦燃烧有一定催化作用，并且Al₂O₃和Fe₂O₃对弱还原性煤显微组分半焦燃烧抑制作用也低于对还原性煤显微组分半焦燃烧的抑制作用。

关键词: 显微组分, 还原性, 热解, 煤燃烧, 反应性, 矿物质

CLC Number:

TQ 546

Yunpeng ZHAO, Haoquan HU, Lijun JIN, Xianyong WEI. Effect of minerals on semi-coke combustion characteristics of maceral with different reducibility[J]. CIESC Journal, 2019, 70(8): 2946-2953.

赵云鹏, 胡浩权, 靳立军, 魏贤勇. 矿物质对不同还原程度煤显微组分半焦燃烧特性影响[J]. 化工学报, 2019, 70(8): 2946-2953.

Figures/Tables 8

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Sample	Proximate analysis/%(mass)			Ultimate analysis (daf)/%(mass)					Petrographic analysis/%(vol)
Sample	M_ad	A_d	V_daf	C	H	N	S	O^①	Vitrinite	Inertinite	Exinite
PSV	4.59	4.56	40.22	81.67	5.08	1.35	1.08	10.82	91.6	5.9	2.5
PSI	3.02	21.87	32.55	80.15	4.49	1.33	0.81	13.23	6.4	89.3	4.3
LWV	11.6	2.68	39.50	77.42	3.96	0.81	0.07	17.74	80.6	17.5	1.9
LWI	12.80	5.53	29.26	78.77	3.36	0.71	0.11	17.05	3.8	95.3	0.9
PSV-Char	5.37	7.40	9.21	89.08	2.76	1.86	0.58	5.72	—	—	—
PSI-Char	3.98	27.24	9.53	89.87	2.68	1.73	0.46	5.26	—	—	—
LWV-Char	7.03	3.96	11.11	89.99	2.51	1.69	0.09	5.82	—	—	—
LWI-Char	7.19	6.92	11.32	89.80	2.72	1.01	0.08	6.39	—	—	—

Sample	Proximate analysis/%(mass)			Ultimate analysis (daf)/%(mass)					Petrographic analysis/%(vol)
Sample	M_ad	A_d	V_daf	C	H	N	S	O^①	Vitrinite	Inertinite	Exinite
PSV	4.59	4.56	40.22	81.67	5.08	1.35	1.08	10.82	91.6	5.9	2.5
PSI	3.02	21.87	32.55	80.15	4.49	1.33	0.81	13.23	6.4	89.3	4.3
LWV	11.6	2.68	39.50	77.42	3.96	0.81	0.07	17.74	80.6	17.5	1.9
LWI	12.80	5.53	29.26	78.77	3.36	0.71	0.11	17.05	3.8	95.3	0.9
PSV-Char	5.37	7.40	9.21	89.08	2.76	1.86	0.58	5.72	—	—	—
PSI-Char	3.98	27.24	9.53	89.87	2.68	1.73	0.46	5.26	—	—	—
LWV-Char	7.03	3.96	11.11	89.99	2.51	1.69	0.09	5.82	—	—	—
LWI-Char	7.19	6.92	11.32	89.80	2.72	1.01	0.08	6.39	—	—	—

Sample	Composition/%(mass)
Sample	SiO₂	Al₂O₃	Fe₂O₃	TiO₂	CaO	MgO	SO₃	K₂O	Na₂O	P₂O₅
PSV	43.71	43.21	1.86	3.30	5.93	0.77	0.15	0.17	0.08	0.82
PSI	46.46	48.77	1.10	1.74	0.77	0.17	0.12	0.14	0.03	0.70
LWV	6.88	9.98	6.79	6.88	34.53	21.21	12.62	0.11	0.91	0.09
LWI	10.47	6.59	17.61	0.14	41.47	15.76	5.66	0.03	2.25	0.02

Sample	Composition/%(mass)
Sample	SiO₂	Al₂O₃	Fe₂O₃	TiO₂	CaO	MgO	SO₃	K₂O	Na₂O	P₂O₅
PSV	43.71	43.21	1.86	3.30	5.93	0.77	0.15	0.17	0.08	0.82
PSI	46.46	48.77	1.10	1.74	0.77	0.17	0.12	0.14	0.03	0.70
LWV	6.88	9.98	6.79	6.88	34.53	21.21	12.62	0.11	0.91	0.09
LWI	10.47	6.59	17.61	0.14	41.47	15.76	5.66	0.03	2.25	0.02

Sample	T _i/℃	T _p/℃	T _f /℃	R _max/(%/℃)
PSV-Char	438	502	557	0.885
PSI-Char	484	510	568	1.007
LWV-Char	415	475	534	0.918
LWI-Char	411	463	533	0.791
PSV-Char Dem	442	505	561	0.985
PSI-Char Dem	452	510	545	1.097
LWV-Char Dem	432	475	526	1.102
LWI-Char Dem	407	422	503	1.040