| 摘要 |
<p>PURPOSE: To shorten time for discharging all of liq. by stopping at least a part of periods corresponding to precipitation phases reaching to max. precipitation velocity, then discharging the liq. from a sedimentation tank with a velocity close to a precipitation velocity of a region wherein particles are freely settled. CONSTITUTION: When a liq. is discharged from an upper part of a sedimentation tank 6, at least a part of periods is stopped corresponding to precipitation phases reaching to max. precipitation velocity, and then the liq. is discharged with a velocity close to a settling velocity VA in a region A wherein particles are freely settled from a sedimentation tank. By the procedure, when neighboring parts of surfaces S of the liq. are discharged with some velocity corresponding to a settling primary velocity VA in a freely settling region A placed directly under submitted region, the settling velocity do not change in each region A, B and C, and is maintained at a constant velocity nealy the same as the primary velocity VA represented by the wavy line A' in a region A, and the discharging periods U2 are very shortened as compared with continuous periods U1 .</p> |
