Working Principle Of The CFB Boiler Economizer

The economizer is an important component of  the CFB boilers, which can save energy, protect the environment, and extend the service life of equipment.

The economizer is an important component of  the CFB boilers, which can save energy, protect the environment, and extend the service life of equipment.

The working principle of the economizer is mainly to use the high-temperature flue gas at the tail of the boiler to exchange heat with the feedwater. When high-temperature flue gas passes through the economizer, heat is transferred to the feedwater inside the pipe through the pipe wall, causing the temperature of the feedwater to gradually increase.

After releasing heat, the temperature of the smoke decreases, thereby achieving the goal of reducing the exhaust temperature and minimizing exhaust heat loss. ‌

Specifically, economizers usually adopt a light tube structure or a finned structure, consisting of multiple parallel serpentine tubes. When the flue gas flows in the economizer, heat is conducted to the feedwater inside the pipe through the metal material of the pipe wall. Meanwhile, due to the flow of smoke and water, heat is transferred between them through convective heat transfer. This heat exchange process not only improves the efficiency of the boiler, saves fuel, but also extends the service life of the equipment.

In addition, the economizer can also prevent water from vaporizing in a stagnant state during boiler start-up. The water in the steam drum is introduced into the economizer through a recirculation pipeline to maintain its flow state and avoid vaporization at low temperatures.