GORMAN-RUPP VG3B3-B, Installation, Operation And Maintenance Manual

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AquaSBR - Sequencing Batch Reactor
Design#: 131349
Option: Bid Design
Project:
Designed By Ed Fritz, Jr., P.E. on Tuesday, June 25, 2013
AUGUSTA CORRECTIONAL CENTER VA
MIXING SYSTEM EQUIPMENT REQUIREMENTS
EFFLUENT DECANTING EQUIPMENT REQUIREMENTS
SLUDGE REMOVAL SYSTEM REQUIREMENTS
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To provide uniform mixing of biological solids to a level typically encountered in activated sludge, approximately 25.0 HP/MG
is necessary with the AquaDDM mixer. The mixing level required is:
Hp-mix = 25.0 HP/MG x Vawl/Basin = 5.9 HP = (4.4 kW)
Based upon the above approximate energy requirements, recommend: (1) - 10.0 NPHP AquaDDM Mixer(s)
To confirm the unit has been selected appropriately, the reactor contents must be completely mixed within 5 minutes. The
selected mixer shall produce a recirculated flow (Qr) of 253,000 GPM, resulting in a turnover time:
Energy Requirements (Hp-mix)
Reactor Turnover Time (Tm)
Average Power Estimation (Pwm)
Tm = Vawl/Basin x 10^6/Qr = 0.9 Minutes
Pwm = NPHP x Lm x 0.7457 x Mixing hrs/cyc. x Nb x Ncdb = 219.5 kW-hr/day
Where:
Lm is the motor loading, typically 88-92% of full nameplate horsepower.
Decant Flow Rate Required at Maximum Design Flow (Qdec)
The decanter shall remove effluent via gravity flow, reducing the water level from the maximum depth to the minimum depth in
the design decant phase time (Tdec). The Decant flow required is:
Qdec = MDV/(Ncdb x Nb x Tdec) = 1,813 GPM = (114.4 l/sec)
The flow rate calculated above is the average rate (from high water level to low water level) at maximum design conditions.
The actual decant flow rate will vary depending on the prevailing driving head, assuming the effluent valves are not throttled,
flow is not pumped, or an orifice plate has not been employed. Refer to design notes for further decanter notes.
Sludge Flow Rate required at Average Design Flow (ADF)
Sludge Flow Rate (Qs):
Sludge will be removed at the end of each cycle at the following rate:
Qs = Vs/(Ncdb x Nb x Tslg) = 100 GPM = (6.3 l/sec)
Sludge Energy Required (Hp-sludge)
Based upon an estimated average driving head of 15.0 ft and an assumed pump efficiency of 60%, the sludge removal
energy required is:
Hp-sludge = (Flowrate x head)/(3,960 x efficiency) = 0.631 BHP = (0.47 kW)
Average Power Estimation (Pws)
Pws = BHP x Tslg x Ncdb x Nb x 0.7457 = 0.622 kW-hr/day
Note: Power estimation assumes sludge is pumped. Refer to design notes for discussion if gravity sludge wasting is
employed.
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Aqua-Aerobic Systems, Inc. CONFIDENTIAL