TM 5-4610-218-12
ble edge weir. The effluent launder is manually ad-
justed by the adjustable support rods (fig. 2-2) to
calcium hypochlorite solution, and when necessary,
permit leveling and skimming of the water surface.
activated carbon are added in the mixing zone.
The clear water is discharged across the slurry pool
(e) As the liquid descends through the mix-
to the wet well tank through the effluent launder
ing zone (fig. 1-4), it is mixed by the circular disks.
connecting tube (fig. 1-4).
The flow is deflected by a series of shallow baffles in
(2) Wet well tank.
the bottom of the erdlator tank and directed in
counter rotating direction into the outer compart-
(a) The wet well tank provides limited stor-
ment, or clarification zone. The resulting counter
age of coagulated water and serves as a sump for
rotation is reduced, but continues at a sufficient ve-
the filter pump.
locity to keep the slurry volume, together with the
(b) An overflow pipe in the wet well tank
clear water above the slurry pool, rotating.
permits operation of the erdlator at rated capacity
(f) The slurry is hydraulically separated
when the filter is stopped. A switch, operated by a
from the clear water in the upper cylindrical section
float in the wet well, activates an alarm bell and a
of the erdlator tank in what is termed the separator
red signal light when the float valve is open.
zone. The slurry level is controlled by a continuous
withdrawal of a small amount of slurry from the top
ated through a lever connected to the float located
of the slurry pool, through the slurry weir box to the
in the wet well tank. This float valve, located in the
sludge concentrator tank.
raw water by-pass, allows additional raw water to
(g) Clear water is collected at the water
enter the system whenever the amount of water in
surface in the effluent launder which acts as a dou-
the wet well falls below a present level.
Figure 2-2. Raw water controls, erdlator top view.
the erdlator tank to the sludge concentrator tank.
(d) A drain in the bottom of the wet well
tank permits complete drainage of the tank to
(b) The sludge concentrator tank functions
waste when water unsuited for filtering is obtained
as a small auxiliary clarifier, It provides a longer
from the erdlator tank.
holding period for slurry concentration and reduces
(3) Sludge concentrator tank.
the water rise rate for separation of clear water
from the slurry.
(a) The woolly slurry flows by gravity from
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