| 摘要 |
<p>PURPOSE:To automatically strip the methane fermentation bacteria sticking excessively on carriers and to reduce running cost by providing respectively >=1 points of throttling parts to the inside surface of a reaction vessel corresponding to the fluidized bed part and sludge blanket layer part of the carriers, thereby fluctuating the fluid state. CONSTITUTION:The throttling part 8 is provided on the fluidized bed part 8 and the sectional area of the flow passage in this section is decreased to increase the ascending speed of waste water and to change the fluid state. Excessively thickened biological membranes are stripped from the carriers by the shearing force generated by such changes. The stripped bacteria are allowed to flow out to the upper sludge blanket layer 3b, where the granules of the methane fermentation bacteria are formed. The throttling part 9 is provided on this sludge blanket layer part 3b as well and the sectional area of the flow passage in this part is decreased to generate disturbance in the fluid state. The rotating motion of the granules and the nuclei of the granules is activated by such disturbance, by which the formation of the granules is accelerated and the aggregation of the granules to each other is prevented. The securer and denser granules are thus obtd.</p> |
