Deaeration Process

Boiler Feed Water Treatment Deaeration Process:

## The process through which the dissolved gases are removed from water is called "Deaeration". The equipment, which is used in this method, is called "Deaerator".

Why do we use deaerators?...

The Deaerator (DA) tank uses steam to preheat boiler feedwater to a temp. at which dissolved O2 & CO2 will become separated from the feedwater before it is pumped to the boiler. The purpose is to protect the boiler and steam/condensate piping from corrosion that would be present when the water evaporates into steam.additional benefit is that the amount of chemicals used to treat the boiler water can be reduced. 

# Dissolved CO2 combines with water to form carbonic acid that causes further corrosion. 

# Working Principle of Deaerators :-

1️⃣ by Henry’s Law- Accordind to William Henry state that gas solubility in a solution decreases as the gas partial pressure above the solution decreases. In simple we can say that The solubility of any gas dissolved in a liquid is directly proportional to the partial pressure of the gas. Solubility of gases decrease with increase in solution temperature and or decrease in pressure.

2️⃣ The second principle state that deaeration is the relationship between gas solubility and temperature. Easily explained, gas solubility in a solution decreases as the temp.of the solution rises and approaches saturation temperature.​​ 

# Main Types of Deaerators:-

1️⃣ Tray type Deaerator 

2️⃣ Spray type Deaerator 

3️⃣ Pressurized type Deaerator