MIL-HDBK-1005/16
For more details, refer to "Industrial Waste Treatment
in Aerated Lagoons" in Advances in Water Quality Improvement,
Mancini and Barnhart, 1968, and to Process Design Techniques for
Industrial Waste Treatment, Adams and Eckenfelder.
c) Temperature Correction. Use Equation 3 for
temperature correction of the rate constant.
K20θ(TL-20)
EQUATION: KT
=
(3)
Rate constant at TL (d-1)
where
KT
=
Rate constant at 20C (d-1)
K20
=
θ
=
1.085 for aerobic lagoons
Temperature of lagoon contents (C)
TL
=
d) Oxygen Requirements. For treatment of normal
domestic sewage in aerobic lagoons, use a value of 1.3 lb O2/lb
applied (1.3 kg O2/kg BOD). Where aerobic lagoons must meet low
effluent BOD requirements, consider using a perforated pipe grid-
air diffusion system. The air bubble curtain effect with this
type of system minimizes short-circuiting and maximizes
effectiveness of lagoon volume. Consult system supplier for
performance data. Alternatively, consider multistaged lagoons
and effluent recycle.
e) Mixing Requirement. No rational method is
available to determine the power input necessary to keep solids
suspended. Consult equipment manufacturers to determine zone of
influence or complete mixing for vendor-supplied aerators.
For lagoon depths of 8 to 18 feet (2.4 to 5.5 m) and suspended
solids concentrations of 1,000 to 5,000 mg/L, provide 60 to
120 horsepower per million gallons (hp/mg) of basin volume. At
depths greater than 12 feet (3.7 m), draft tubes may be required.
For lesser depths, provide at least 30 hp/mg of basin volume.
Consult the aerator manufacturer about the need for anti-erosion
assemblies or special protection features to protect the pond
bottom from eroding under the influence of mechanical surface
aerators. Locate individual surface aerators for overlap of zone
of influence. Use several small units rather than fewer large
units to minimize the effect of downtime.
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