Separation Process of Fine Coals by Ultrasonic Vibration Gas-Solid Fluidized Bed

Table 1

Sulfur content of each layer of product.

Layer number	Sulfur content/%
	0 Hz	20 kHz	25 kHz	30 kHz	35 kHz	40 kHz
First layer	1.52	1.38	1.35	1.33	1.26	1.48
Second layer	2.11	1.96	1.93	1.86	1.82	1.98
Third layer	2.23	2.18	2.26	2.14	2.22	2.08
Forth layer	2.26	2.32	2.35	2.28	2.25	2.29
Fifth layer	6.56	6.75	6.73	6.68	6.89	6.77