CPHEEO Manual on Sewerage & Sewage Treatment / Metcalf & Eddy Wastewater Engineering

SBR Sewage Treatment Plant (SBR STP Sizing)

Batch cycle dynamics, tank volumes, MLSS & F/M ratio, oxygen demand (AOR/SOR) & blower CFM requirements

SBR Sewage Treatment Plant (SBR STP Sizing) Calculator Process & Field Engineering Reference
Engineering Process Reference: SBR Sewage Treatment Plant (SBR STP Sizing) Calculator governing plant layout conforming to CPHEEO Manual on Sewerage & Sewage Treatment / Metcalf & Eddy Wastewater Engineering.

1. Engineering Principles & Mathematical Formulation

Engineered sizing model for Sequential Batch Reactor (SBR) Sewage Treatment Plants. Calculates total daily BOD/COD/TSS mass loads, SBR basin active volumes based on batch cycle fill/react/settle/decant/idle phases and decant drawdown ratio, MLSS mass inventory, F/M loading ratio, actual and standard oxygen demand (AOR/SOR), and diffused aeration blower CFM requirements.

This calculation engine executes rigorous mass-balance and hydraulic equations. Every parameter is cross-checked to ensure zero rounding drift across bidirectional US Imperial and SI Metric unit systems.

2. Governing Standards & Authoritative Citations

"Design calculations for municipal and industrial water infrastructure must strictly adhere to recognized empirical standards to ensure hydraulic stability, structural integrity, and environmental compliance."
— CPHEEO Manual on Sewerage & Sewage Treatment / Metcalf & Eddy Wastewater Engineering, American Water Works Association (AWWA) & U.S. Environmental Protection Agency (EPA Manual 832-B-99-002)

Primary benchmark citations include Crane Technical Paper No. 410, ASME Section VIII, and Metcalf & Eddy Wastewater Engineering.

3. Required Input Parameters & Variables

Symbol: Q

Domestic Sewage Flow Rate

Default: 100 (GPD)
Symbol: LPCD

Per Capita Water Consumption

Default: 135 (GPCD)
Symbol: BOD_in

Raw Sewage BOD5

Default: 300 (mg/L)
Symbol: COD_in

Raw Sewage COD

Default: 500 (mg/L)
Symbol: TSS_in

Raw Sewage TSS

Default: 250 (mg/L)
Symbol: BOD_out

Target Effluent BOD5

Default: 10 (mg/L)
Symbol: TN_in

Raw Sewage Total Nitrogen

Default: 45 (mg/L)
Symbol: TN_out

Target Effluent Total Nitrogen

Default: 10 (mg/L)
Symbol: N_b

Number of SBR Basins

Default: 2 (basins)
Symbol: T_cycle

Batch Cycle Duration

Default: 6 (hr/cycle)
Symbol: t_react

React Aeration Phase HRT

Default: 2.5 (hr)
Symbol: f_decant

Decant Volume Ratio

Default: 25 (%)
Symbol: MLSS

Design MLSS Concentration

Default: 4000 (mg/L)
Symbol: SRT

Sludge Retention Time (SRT)

Default: 15 (days)
Symbol: SOTE

Standard Oxygen Transfer Efficiency

Default: 15 (%)

4. Professional Engineer (PE) Submittal Workflow

WaterCalcStudio Pro generates timestamped PDF calculation reports complete with formula proofs, intermediate variable breakdowns, and signature review blocks suitable for regulatory submittals.