Table 4. Orthogonal Experimental Design for −3 + 1 mm Lignite.

		factor A	factor B	factor C	factor D	response
std	run	inlet temperature (°C)	pulsating frequency (Hz)	air velocity (m/s)	bed height (mm)	σash (—)
22	1	100.00	3.06	0.61	80.00	21.02
4	2	100.00	3.49	0.61	100.00	20.48
2	3	100.00	3.49	0.48	100.00	20.02
19	4	110.00	3.49	0.55	60.00	21.78
13	5	90.00	3.49	0.48	80.00	22.58
15	6	110.00	3.49	0.48	80.00	23.73
29	7	100.00	3.49	0.55	80.00	24.86
28	8	100.00	3.49	0.55	80.00	24.56
7	9	90.00	3.93	0.55	80.00	23.71
26	10	100.00	3.49	0.55	80.00	24.78
14	11	90.00	3.49	0.61	80.00	23.50
9	12	100.00	3.06	0.55	60.00	21.17
20	13	110.00	3.49	0.55	100.00	23.47
17	14	90.00	3.49	0.55	60.00	24.09
3	15	100.00	3.49	0.61	60.00	20.03
1	16	100.00	3.49	0.48	60.00	21.48
25	17	100.00	3.49	0.55	80.00	24.55
21	18	100.00	3.06	0.48	80.00	21.69
8	19	110.00	3.93	0.55	80.00	23.90
27	20	100.00	3.49	0.55	80.00	24.99
23	21	100.00	3.93	0.48	80.00	21.79
10	22	100.00	3.06	0.55	100.00	21.90
5	23	90.00	3.06	0.55	80.00	24.08
6	24	110.00	3.06	0.55	80.00	22.19
18	25	90.00	3.49	0.55	100.00	22.99
24	26	100.00	3.93	0.61	80.00	19.34
12	27	100.00	3.93	0.55	100.00	20.40
11	28	100.00	3.93	0.55	60.00	21.11
16	29	110.00	3.49	0.61	80.00	21.20