Boiler economizers work by transferring heat from the flue gases to the boiler feedwater. The flue gases are typically hot, around 300-500 degrees Fahrenheit, and the boiler feedwater is typically cold, around 100-150 degrees Fahrenheit. The heat from the flue gases is transferred to the boiler feedwater, which raises the water’s temperature. The heated water is then used to make steam or hot water.
There are two main types of boiler economizers: condensing and non-condensing.
Condensing economizers: Condensing economizers are the most efficient type of economizer. They work by cooling the flue gases below their condensation temperature, which allows the water vapor in the flue gases to condense and release its latent heat. This latent heat is then transferred to the boiler feedwater.
Non-condensing economizers: Non-condensing economizers do not cool the flue gases below their condensation temperature. They are less efficient than condensing economizers, but they are also less expensive.
The most common type of boiler economizer is the shell-and-tube economizer. This type of economizer is made up of a shell and a series of tubes. The flue gases flow through the shell, and the boiler feedwater flows through the tubes. The heat from the flue gases is transferred to the boiler feedwater through the tubes.
Plate economizers are also a common type of boiler economizer. This type of economizer is made up of a series of plates that are arranged in a parallel or staggered pattern. The flue gases flow through the plates, and the boiler feedwater flows between the plates. The heat from the flue gases is transferred to the boiler feedwater through the plates.
Boiler economizers can be installed on new boilers or retrofitted to existing boilers. The cost of installing a boiler economizer can vary depending on the size and type of boiler. However, the savings on fuel costs can typically offset the cost of the economizer within a few years.
Here are some of the factors that affect the efficiency of a boiler economizer:
The temperature of the flue gases
The temperature of the boiler feedwater
The type of economizer
The size of the economizer
The installation of the economizer