| 摘要 |
<p>1,215,865. Sedimentation control. REDERI AB NORDSTJERNAN. 28 June, 1968 [30 June, 1967], No. 30980/68. Heading BID. [Also in Division G1] Liquid containing suspended solids enters tank 5 at inlet 1, clarified liquid overflows at 2 and concentrated sludge is pumped out at 3, the inlet or sludge outlet flow being so controlled as to optimise separation, the sludge being then at its most concentrated consistent with a clear liquid effluent. Under these conditions a sharp level 4 is observed where solids concentration varies abruptly, and the flow is controlled to hold this level 4 between the mouths of two tubes 6 which are filled with clarified liquid and lead to an oil-filled inverted U-tube serving as a differential pressure gauge. The level of the oil-liquid interface is monitored by photocell 8 and used to control the sludge pump 9 automatically. Alternatively, the level is merely observed and control is manual. Sedimentation is assisted by vibrations applied directly to the liquid, at 10, or to the tank wall. The wide part of the righthand leg of the U-tube magnifies the interface movement in the left-hand leg as differential pressures vary. Fig. 5 shows a simple settling tank, but the invention also applies to a tank divided by inclined baffles into compartments which operate as parallel settling zones (Fig. 4, not shown).</p> |
