1. What is Influent Substrate Concentration?

Definition: Influent Substrate Concentration refers to the concentration of organic matter or nutrients in the raw wastewater entering a treatment plant.

Purpose: It helps wastewater treatment professionals determine the organic load entering the system for proper treatment design and operation.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S_o \) — Influent Substrate Concentration (kg/m³)
• \( V_L \) — Organic Loading (kg/m³)
• \( V \) — Reactor Volume (m³)
• \( Q_i \) — Influent Average Flow Rate (m³/s)

Explanation: The formula calculates the substrate concentration by multiplying the organic loading by reactor volume and dividing by the flow rate.

3. Importance of Substrate Concentration Calculation

Details: Proper calculation ensures efficient wastewater treatment system design, helps predict treatment performance, and prevents system overload.

4. Using the Calculator

Tips: Enter organic loading in kg/m³, reactor volume in m³, and flow rate in m³/s. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is typical organic loading for domestic wastewater?
A: Typically ranges from 0.1 to 0.4 kg BOD/m³·day for domestic wastewater.

Q2: How does reactor volume affect substrate concentration?
A: Larger reactor volumes can handle higher organic loads but require more space and resources.

Q3: What units should I use for flow rate?
A: The calculator uses m³/s, but you can convert from other units (1 m³/day = 0.000011574 m³/s).

Q4: What factors affect substrate concentration?
A: Population served, industrial contributions, and water consumption patterns all affect influent concentration.

Q5: How accurate is this calculation?
A: It provides theoretical values; actual concentrations may vary due to diurnal flow variations and seasonal changes.