How many types of diffusers, calculation and formula?
A diffuser is a device that is used to distribute air or other gases into a liquid, such as water. The purpose of a diffuser is to increase the surface area of the gas that comes into contact with the liquid, thus promoting the transfer of oxygen and other gases into the liquid. This is an important process in many industries, including wastewater treatment, aquaculture, and agriculture. There are two main types of diffusers: coarse bubble diffusers and fine bubble diffusers.
In this blog, we will explore these two types of diffusers in detail, including their calculation and formula, and the tanks in which they are used.
Coarse Bubble Diffusers
Coarse bubble diffusers, as their name suggests, release large bubbles into the liquid. These bubbles are typically between 3 and 8 millimeters in diameter. Coarse bubble diffusers are used in tanks with a depth of 6 meters or more. They are most commonly used in wastewater treatment plants, where they are used to aerate the wastewater and promote the growth of bacteria that break down organic matter. Coarse bubble diffusers are also used in fish tanks, where they help to maintain oxygen levels for the fish.
Calculation and Formula
The amount of air that needs to be diffused into the liquid depends on several factors, including the depth of the tank, the temperature of the liquid, and the desired dissolved oxygen concentration. The formula for calculating the amount of air required is:
Q = (D.O. x A x T x K2) / (C x K1)
Q = Flow rate of air required (m3/hr) D.O. = Desired dissolved oxygen concentration (mg/l) A = Surface area of the liquid (m2) T = Temperature of the liquid (°C) K1 = Oxygen transfer efficiency coefficient (typically 0.8 to 1.0) K2 = Correction factor for temperature (typically 1.024 at 20°C) C = Oxygen transfer rate (kg O2/kWh)
Fine Bubble Diffusers
Fine bubble diffusers release much smaller bubbles into the liquid than coarse bubble diffusers. These bubbles are typically between 0.5 and 2 millimeters in diameter. Fine bubble diffusers are used in tanks with a depth of less than 6 meters. They are commonly used in wastewater treatment plants, aquaculture systems, and hydroponic systems. Fine bubble diffusers are preferred over coarse bubble diffusers in these applications because they provide more uniform aeration and higher oxygen transfer efficiency.
Calculation and Formula
The formula for calculating the amount of air required for fine bubble diffusers is the same as for coarse bubble diffusers. However, the oxygen transfer rate (C) is different for fine bubble diffusers. The oxygen transfer rate for fine bubble diffusers is typically between 1.5 and 2.5 kg O2/kWh.
In conclusion, diffusers are an important part of many industrial processes. Coarse bubble diffusers are used in tanks with a depth of 6 meters or more, while fine bubble diffusers are used in tanks with a depth of less than 6 meters. The calculation and formula for determining the amount of air required for diffusers depends on several factors, including the depth of the tank, the temperature of the liquid, and the desired dissolved oxygen concentration. By using the correct type of diffuser and the correct amount of air, industries can promote the growth of bacteria, maintain oxygen levels for fish, and promote plant growth in hydroponic systems.