Lamont Boiler – Parts, Construction, Working and Advamtages

The Lamont Boiler is the first forced convection boiler. It is a high-pressure water tube, forced circulation externally fired. boiler. It was named the Lamont Boiler because it was introduced by Douglas La-Mont in the year 1925.
In lamont boiler, an external water tube pump is used to circulate water within the water tubes of the boiler. So, the pressure of water in the tubes is higher compared with the pressure of water in a natural circulation boiler.

Lamont Boiler is mainly used in power plant industries to generate electricity.

Parts Of Lamont Boiler:

These are the main parts of the Lamont Boiler:

1) Feed Pump:
Feed Pump supplies water into the boiler from the hot well.

2) Economiser:
An economiser is used to increase the temperature of feed water to some extent.

3) Centrifugal Pump:
A centrifugal pump is used to circulate water inside the Lamont Boiler, as it is a forced-circulation boiler. The pump is driven by a steam turbine, and the steam for this turbine is taken by the boiler. This boiler uses its own steam to drive the pump that circulates water in it.

4) Steam Seperating Drum:
The role of this part of the Lamont Boiler is indicated by its name. It separates steam from water.

5) Super Heater:
Steam generated from the evaporator is saturated steam, and if used in a steam turbine can cause corrosion on the turbine. So the saturated steam is sent to the superheater, where it converts into superheated steam, and this superheated steam is sent to the turbine.

6) Radiant Evaporator:
Radiant Evaporator heats the water with the help of radiation. It is located near the furnace.

7) Convective Evaporator:The
Convective Evaporator is located above the Radiant Evaporator. It heats the water by a convection process.

8)Air preheater:
An air preheater is present near the top of the Lamont Boiler. Its main function is to improve the thermal efficiency of the boiler by preheating the air coming from the blower, and this preheated air is sent to the furnace.

9) Blower:
It blows the air into the air preheater, which is further sent to the furnace to increase the efficiency of the boiler.

Construction of Lamont Boiler:

• In lamont boiler, the air blower is connected to the air preheater and supplies air to it. This air preheater is connected to the furnace.
• The water feed pump is connected to the economiser, which preheats the water, and this economiser is connected to the steam separator drum.
• The Steam separator drum is connected to the radiant evaporator, which is located near the combustion chamber, and this radiant evaporator is connected to the convective evaporator, which is present above it.
• The steam separator drum is also connected to the superheater, which further heats the air to the desired level and then transfers the steam to the turbine to produce electricity.

Working Of Lamont Boiler:

• At first, the air blower will blow air to the air preheater, where air is preheated and sent to the furnace to increase the thermal efficiency of the boiler.
• On the otherside, the water feed pump circulates the water into the economiser of the boiler. The economiser heats the water to some extent and this water is sent to the steam separator drum.
• After the steam separator drum, this water is forced circulated through the radiant evaporator by the external centrifugal pump, which is driven by a steam turbine. Radiant evaporator heats the water and converts some portion of the water into steam.
• Water and steam mixture from the radiant evaporator is sent to the convective evaporator. In a convective evaporator, water is further heated, and most of the water converts into saturated steam. Water passes from these two evaporators 10 – 15 times until almost all the water converts into saturated steam.
• The mixture of saturated steam and water is then sent to the steam separator drum to separate the steam from the water. In the steam separator drum, the steam is collected at the upper portion of the drum, and the remaining water settles down.
• This saturated steam present in the steam separator drum cannot be sent to the turbine directly as it will cause corrosion in the turbine. So, the saturated steam is passed through a superheater where the temperature of the steam is increased to the desired level and saturated steam converts into superheated steam.
• After that, this superheated steam is either sent to the steam collecting drum or sent to the turbine to produce electricity.
• Also, air from the air preheater reaches the furnace where the fuel burns. The flue gases from the furnace first heat the evaporator and then pass by the superheater. These gases, after passing through the superheater, reach the air preheater and are used to preheat the air before reaching the furnace.

Advantages of Lamont Boiler:

1) Lamont Boiler has a very flexible and simple design.
2) It has a high heat transfer rate.
3) This boiler has a high heat transfer rate.
4) It has a very high steam-generating capacity (about 50 tonnes per hour ).