Hydraulic Retention Time Calculator
Calculate hydraulic retention time (HRT) and volumetric organic loading rates for bioreactors and wastewater systems.
Calculation Parameters
Input your parameters below.
Calculated Result
Expert Tip
Make sure all values are in the correct units to ensure mathematically precise chemical results.
How this Calculator Works
This calculator allows you to solve Hydraulic Retention Time problems dynamically. Adjust the input parameters using the sliders or selection menu below:
- Reactor Volume (V, m³) (Range: 10 to 2500, Default: 1000)
- Influent Flow Rate (Q, m³/day) (Range: 10 to 1500, Default: 500)
- Influent Organic COD/BOD (S₀, mg/L) (Range: 50 to 1000, Default: 300)
The results are computed instantly and updated in the results panel on the right.
Formula & Methodology
Where:
- Reactor Volume: Parameter value.
- Influent Flow Rate: Parameter value.
- Influent Organic COD/BOD: Parameter value.
Step-by-Step Calculation Example
To calculate Hydraulic Retention Time manually, follow these steps:
- Identify the input parameters. For example:
- Reactor Volume (V, m³) = 1000
- Influent Flow Rate (Q, m³/day) = 500
- Influent Organic COD/BOD (S₀, mg/L) = 300
- Apply the formula:
HRT = (V / Q) · 24 (hours)
- Verify the calculated value which is updated instantly in the results panel on the right.
Frequently Asked Questions
What is Hydraulic Retention Time (HRT)? ▼
HRT measures the average length of time a soluble compound remains in a bioreactor or reactor vessel.
What is the HRT formula? ▼
HRT = Reactor Volume (V) / Influent Volumetric Flow Rate (Q).
How does HRT differ from Solids Retention Time (SRT)? ▼
HRT measures liquid residence time, whereas SRT (sludge age) measures microbial biomass residence time in activated sludge systems.