| 摘要 |
PURPOSE:To improve the selectivity by constituting a 1st storage tank wherein fine powder coal/water slurry is stored and a bubble mixing device, is built-in and a 2nd storage tank which is opened at the upper part with an overflow opening slightly below the upper part and a discharge port at the lower part, and a specified flotation pipe. CONSTITUTION:The coal/water mixed slurry 20 stored in the 1st storage tank 25 is sent with bubbles to the flotation pipe 30. In this case, a large amount of slurry is discharged and a part of the discharged slurry is returned to the 1st storage tank 25, and by this operation large bubbles are released and only the small bubbles are used. And the residence time of the slurry is prolonged by the fixing angle of the flotation pipe 30. In the flotation pipe 30, coal, water and bubbles are flowed, and the bubbles are stuck to the particles of coal, which is positioned in the upper layer at the outlet, and the bubbles are not stuck to the particles of ash, which is positioned in the lower layer as a slurry, and both are introduced to the 2nd storage tank 31 provided with the overflow port 32 positioned at almost the same level with the connecting hole 30a of the flotation pipe 30. By controlled said level, re-mixing of coal and ash is prevented. |
