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
Where the assumed system losses account for 0.20 PSIG blower discharge losses, 0.50 PSIG piping losses from blower to
diffuser, and 1.30 PSIG diffuser losses.
Average Discharge Pressure (Pda) = 8.96 PSIG = (61.85 KPA)
Maximum Discharge Pressure (Pdm) = 10.67 PSIG = (73.60 KPA)
Average Blower Power Estimate
1. Estimated Average Power Draw (BHP)
The following is a general equation that estimates the power draw of the blower at the average oxygen demand and average
pressure. While the actual blower selection shall be made from manufacturer supplied curves, programs, or
recommendations at maximum conditions, this equation shall be used to estimate the annual average aeration power. Unless
stated otherwise, a blower efficiency (e) of 0.70 shall be used (typical range 0.60 to 0.70).
BHP = 0.227 x ICFM x [((Pa + Pda)/Pa)^0.283 – 1]/e = 47.9 BHP = (35.7 kW)
2. Estimated Daily Power Required for Blowers (Pwa)
Pwa = (BHP x 0.7457 x At x Ncdb x Nb) = 275.9 kW-hr/day
Blower Selection
1. Blower Recommendation
The actual blower and motor sizing must consider inlet conditions under operating temperature and pressure extremes. Motor
size, for example, must be selected to handle inlet air at maximum density, which occurs at lowest operating temperatures.
Blower size must be selected to deliver the required air volume at minimum density (maximum operating temperature)
throughout the range of pressures. The following has been recommended to meet the design extremes:
Number of Blowers Operating/Basin:
Number of Total Blower Operating:
Number of Standby Units:
Total Number of Installed Units:
Motor Size of Each Blower:
Airflow Capacity of Each Blower:
Maximum Design Discharge Pressure:
= 2
= 2
= 1
= 3
= 40 HP
= 445 SCFM
= 10.7 PSIG
= 29.8 kW
= 12.6 m³/min
= 73.6 KPA
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Aqua-Aerobic Systems, Inc. CONFIDENTIAL