Flocculation Tank Design Calculation

Velocity Gradient Formula:

\[ G = \sqrt{\frac{P}{\mu V}} \]

Velocity Gradient (G):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Velocity Gradient for Flocculation Tank?

The velocity gradient (G) is a key parameter in flocculation tank design that represents the root mean square velocity gradient in the fluid. It quantifies the intensity of mixing and influences the rate of particle collisions and floc formation in water treatment processes.

2. How Does the Calculator Work?

The calculator uses the velocity gradient formula:

\[ G = \sqrt{\frac{P}{\mu V}} \]

Where:

\( G \) — Velocity gradient (s⁻¹)
\( P \) — Power input (W)
\( \mu \) — Dynamic viscosity (Pa·s)
\( V \) — Volume of the flocculation tank (m³)

Explanation: The formula calculates the root mean square velocity gradient based on the power input per unit volume, considering the fluid's viscosity.

3. Importance of Velocity Gradient Calculation

Details: Proper velocity gradient calculation is essential for designing effective flocculation systems. It determines the mixing intensity needed to promote particle collisions while preventing floc breakup, directly impacting treatment efficiency.

4. Using the Calculator

Tips: Enter power in watts, viscosity in pascal-seconds, and volume in cubic meters. All values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for G values in flocculation?
A: Typically 20-100 s⁻¹, with lower values for gentle flocculation and higher values for rapid mixing.

Q2: How does viscosity affect the velocity gradient?
A: Higher viscosity reduces the velocity gradient for a given power input, requiring more power to achieve the same mixing intensity.

Q3: Why is velocity gradient important in water treatment?
A: It controls the rate of particle collisions and floc formation, directly impacting the efficiency of solid-liquid separation processes.

Q4: How does temperature affect the calculation?
A: Temperature affects viscosity (μ), with higher temperatures decreasing viscosity and thus increasing the velocity gradient for the same power input.

Q5: What are common power sources for flocculation?
A: Mechanical mixers (paddles, turbines), hydraulic mixing, or pneumatic mixing systems are commonly used to provide the necessary power input.