Discover Water Tube Boilers 5 Types, Pros, Cons, and Uses [PDF]

In this article, we shall explore the advantages, disadvantages, and applications of water tube boilers. We have provided a PDF for the same.

Introduction to Water Tube Boilers

Water tube boilers are a type of boiler commonly used in industrial settings to generate steam. They are distinct from traditional fire tube boilers, which rely on hot gases from combustion to heat water in a vessel. Water tube boilers use a network of tubes for water circulation and this water is heated by the hot gases that flow over the tubes.

Such designs of water tube boilers provide greater efficiency and higher steam generation rates thereby making water one of the best choices for power generation for higher capacities in industries like industrial or chemical processing. Examples of water tube boilers include the following

• Lamont boiler
• Benson boiler
• Babcock and Wilcox boiler
• Yarrow boiler
• Loeffler Boiler

Types Of Water Tube Boilers

The Different types of water tube boilers are as follows

• Stirling Boiler: A Stirling boiler uses a chain of tubes that are bent in a serpentine shape to increase the surface area for heat transfer. The design allows for efficient heating of water and steam production.
• Babcock and Wilcox Boiler: The Babcock and Wilcox boiler is a type of water tube boiler that uses inclined tubes to create a high-heat transfer area. This boiler is commonly used in power generation and other industrial applications.
• Yarrow Boiler: A Yarrow boiler is a compact, highly efficient water tube boiler that features a circular combustion chamber and multiple small-diameter tubes. This design allows for quick steam production and efficient heat transfer.
• The Benson boiler is a high-pressure steam generator that uses the principle of forced circulation. It was invented by Mark Benson in 1922 and is commonly used in power plants. The Benson boiler operates at extremely high temperatures and pressures, resulting in greater efficiency and reduced emissions.
• The Lamont boiler is a type of water-tube boiler that uses forced circulation of water through a series of tubes. It was invented by Walter Douglas Lamont in 1925 and is commonly used in power plants. The Lamont boiler operates at high pressures and temperatures, which increases its efficiency and reduces fuel consumption.

Parts of Water Tube Boilers

The different parts of water tube boilers are as follows

• Furnace: It’s the combustion chamber where fuel is burned to produce heat.
• Tubes: Water-filled tubes that carry heated gases from the furnace to the boiler’s inlet header.
• Inlet Header: Collects hot gases from the furnace and distributes them to the boiler’s tubes.
• Outlet Header: Collects cooled gases from the tubes and discharges them to the chimney.
• Water Walls: Tubes that circulate water around the furnace and prevent it from overheating.
• Superheater: A section of the boiler that further heats steam to a high temperature to improve its thermal efficiency.
• Economizer: A device that recovers heat from exhaust gases to preheat boiler feedwater.
• Air Preheater: A device that warms up combustion air before it enters the furnace, improving combustion efficiency.
• Burners: Devices that inject fuel and air into the furnace for combustion.
• Chimney: An exhaust duct that releases gases into the atmosphere.

Working Principle of Water Tube Boilers

Water tube boilers operate on the principle of forced water circulation. The boiler consists of a large number of interconnected water-filled tubes that are placed inside a furnace. Burners heat the fuel and produce hot gases, which enter the inlet header of the boiler and pass through the tubes. Heat is transferred to the surrounding water when gases pass through the tubes. The water is then collected in the steam drum once it is converted to steam

The steam is further heated in the superheater section and then distributed to various parts of the plant. The cooled gases leave the boiler through the outlet header and are discharged into the atmosphere through the chimney. This cycle repeats continuously, providing a steady supply of steam.

Advantages of Water Tube Boilers

• The maximum working pressure of the water tube boiler is 250 bar.
• Overall efficiency is up to 90% with an economizer.
• It requires less floor area for a given output.
• It requires less floor area for a given output.
• The rate of steam generation and the quality of steam for suitable power generation are much better.
• This can be used in large power plants.
• The direction of water circulation is well-defined.

Disadvantages of Water Tube Boilers

• Complex design and High maintenance cost.
• A skilled operator is required for operation.
• This is used in large power plants and it is uneconomical for use in small industries.
• For the same power output, the cost of a water tube boiler is high.
• Treatment of feed water is very essential in a water tube boiler as small-scale deposits inside the tube can cause overheating and bursting.

Application of Water Tube Boilers

• Sugar Mill: In the Sugar industry the power for turbines and machinery is generated by steam from water boilers
• Chemical Industry: Various chemical processes such as drying, distillation, evaporation, etc make use of steam generated from water tube boilers
• Paper Mill: In Paper making industry steam generated from water tube boilers is used for bleaching, drying, and pulping.
• Textile Factory: The steam required in the textile sector for drying, dyeing, and finishing is also produced by water tube boilers.
• Central Heating Enterprise: In residential, and commercial buildings to provide central heating and cooling we employ water tube boilers
• Power Plant: Power plants used for electricity generation using steam is done by water boilers

Conclusion

In conclusion, like two sides of a coin water tube boilers are better than fire tube boilers for their high efficiency, ability to handle high pressure or high temperature, and provide increased safety while having disadvantages like design complexity, and the higher cost involved. Lastly,, the decision to choose one of the two types depends on the user’s requirements and the application intended. Despite their disadvantages, they are extensively used in petrochemcial, manufacturing and power generation industries

References

• WIkipedia