Sewage Inflow Per Day Given Sludge Age Calculator

Sewage Discharge Formula:

\[ Q_s = \frac{\left(\frac{V \times X'}{\theta_c}\right) - \left(Q_w \times (X_R - X_E)\right)}{X_E} \]

Volume of Tank:

m³

Mixed Liquor Suspended Solids:

kg/m³

Sludge Age:

seconds

Volume of Wasted Sludge per day:

m³/s

Concentration of Solids in Returned Sludge:

kg/m³

Concentration of Solids in Effluent:

kg/m³

Sewage Discharge:

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1. What is the Sewage Discharge Formula?

The Sewage Discharge Formula calculates the flow rate of sewage when it is being discharged in the river, taking into account various parameters of the wastewater treatment process including tank volume, suspended solids concentration, sludge age, and concentrations of solids in different streams.

2. How Does the Calculator Work?

The calculator uses the Sewage Discharge formula:

\[ Q_s = \frac{\left(\frac{V \times X'}{\theta_c}\right) - \left(Q_w \times (X_R - X_E)\right)}{X_E} \]

Where:

\( Q_s \) — Sewage Discharge (m³/s)
\( V \) — Volume of Tank (m³)
\( X' \) — Mixed Liquor Suspended Solids (kg/m³)
\( \theta_c \) — Sludge Age (seconds)
\( Q_w \) — Volume of Wasted Sludge per day (m³/s)
\( X_R \) — Concentration of Solids in Returned Sludge (kg/m³)
\( X_E \) — Concentration of Solids in Effluent (kg/m³)

Explanation: The formula calculates sewage discharge by considering the mass balance of solids in the wastewater treatment system, accounting for sludge production, wasting, and effluent quality.

3. Importance of Sewage Discharge Calculation

Details: Accurate sewage discharge calculation is crucial for designing and operating wastewater treatment plants, ensuring regulatory compliance, protecting receiving water bodies, and optimizing treatment processes.

4. Using the Calculator

Tips: Enter all values in the specified units. Ensure all values are positive and valid for accurate calculation. The calculator provides sewage discharge in cubic meters per second.

5. Frequently Asked Questions (FAQ)

Q1: What is the significance of sludge age in this calculation?
A: Sludge age represents the average time solids remain in the system and affects the biological treatment efficiency and sludge production rates.

Q2: Why is the concentration of solids in effluent important?
A: Effluent solids concentration determines the quality of treated wastewater and compliance with discharge regulations.

Q3: How does wasted sludge volume affect sewage discharge?
A: Wasted sludge removes solids from the system, which impacts the mass balance and ultimately affects the calculated sewage discharge rate.

Q4: What are typical values for mixed liquor suspended solids?
A: Typical MLSS values range from 2000-4000 mg/L (2-4 kg/m³) in conventional activated sludge systems.

Q5: How can this calculation help in plant operation?
A: This calculation helps operators understand the relationship between different process parameters and optimize treatment performance while meeting discharge requirements.