A boiler is an enclosed vessel in which a fluid such as water is heated to produce steam or the vaporized form of a liquid. The steam or hot water is then circulated through a piping system, to transfer heat for various applications such as heating, power generation and other processes. Boilers and associated systems are efficient heat exchange systems; however, they can be dangerous if not properly maintained and operated. Boilers are commonly fueled by natural gas, oil, or electricity, and can come in various sizes and types, including conventional boilers, system boilers, and combination boilers. They are often used as an alternative to furnaces, particularly in areas where natural gas is readily available. Boilers can be used for both residential and commercial applications, and are generally considered to be efficient and reliable heating systems.
1. Boiler purposes
1.1. Space heating
Boilers are commonly used to heat buildings and homes by circulating hot water or steam through radiators or underfloor heating systems.
1.2. Hot water supply
Boilers can be used to provide hot water for domestic use, such as bathing and washing dishes.
1.3. Industrial processes
Boilers are used in many industrial processes, such as power generation, chemical processing, and food processing, to provide heat or steam for various applications.
Boilers can be used in cogeneration systems, which produce both electricity and heat from a single fuel source.
1.5. District heating
Boilers can be used in district heating systems, which supply heat to multiple buildings from a central location.
1.6. Snow melting
Boilers can be used to melt snow and ice on sidewalks, driveways, and other outdoor surfaces.
Overall, boilers are versatile and efficient heating systems that can be used for a wide range of applications.
2. Types of Boiler and Classifications of Boiler:
There are the following Boiler Types:
2.1. According to the position of water and hot gasses
Fire Tube Boiler: A fire tube boiler is a type of boiler in which hot gases from a fire pass through one or more tubes running through a sealed container of water. The heat of the gases is transferred through the walls of the tubes by thermal conduction, heating the water and ultimately creating steam. The steam produced is used for various applications such as power generation, heating, and industrial processes.
Water Tube Boiler: A water tube boiler is a type of boiler that uses a network of tubes filled with water to create hot gases and steam. The tubes are arranged in a way that maximizes heat transfer and efficiency, and they can be straight or bent depending on the design. Water tube boilers are commonly used in industrial applications and power plants, where they can generate large amounts of steam for various processes.
2.2. According to Axis of Shell
Horizontal Boiler: A horizontal boiler is a type of boiler that has a horizontal cylindrical shell containing a cylindrical furnace, tubes, and a smokebox, with the stack located at the rear of the shell. The boiler is designed to operate with a maximum operating pressure of up to 250 psi and a temperature of up to 450°F.
Vertical Boiler: A vertical boiler is a type of boiler that has a vertically oriented cylindrical shell containing a furnace, tubes, and a smokebox, with the stack located at the top of the shell. The boiler is designed to operate with a maximum operating pressure of up to 300 psi and a temperature of up to 500°F.
2.3. According to the pressure
Low-Pressure Boiler: A low-pressure boiler is a type of boiler that operates at a maximum working pressure of 15 psi or a maximum operating temperature of 250°F. These boilers are generally used for heating buildings and other low-temperature processes.
High-Pressure Boiler: A high-pressure boiler is a type of boiler that operates at a pressure above 15 psi or a temperature above 250°F. These boilers are typically used in industrial applications, such as power generation, where they can produce large amounts of steam to drive turbines and other equipment.
2.4. According to the method of circulation
Natural Circulation Boiler: A natural circulation boiler is a type of boiler that operates without the use of a pump to circulate water. The circulation of water in these boilers is due to natural convection currents, which are generated by the density difference between the heated water in the boiler and the cooler water in the return circuit.
Forced Circulation Boiler: A forced circulation boiler is a type of boiler that uses a pump to circulate water through the boiler and the steam-generating tubes. The pump creates a forced flow of water through the tubes, which enhances heat transfer and increases the efficiency of the boiler.
2.5. According to fuel firing
Solid fuel-fired Boiler: A solid fuel-fired boiler is a type of boiler that uses solid fuel, such as coal, wood, or biomass, as the primary fuel source for combustion. The fuel is burned in a furnace or combustion chamber, which generates heat that is transferred to the water in the boiler through a series of tubes.
Liquid fuel-fired Boiler: A liquid fuel-fired boiler is a type of boiler that uses liquid fuel, such as diesel, heavy oil, or kerosene, as the primary fuel source for combustion. The fuel is atomized and sprayed into the combustion chamber, where it is ignited and generates heat that is transferred to the water in the boiler through a series of tubes.
Gaseous fuel-fired Boiler: A gaseous fuel-fired boiler is a type of boiler that uses gaseous fuels, such as natural gas, propane, or biogas, as the primary fuel source for combustion. The fuel is burned in a combustion chamber or furnace, which generates heat that is transferred to the water in the boiler through a series of tubes.
3. Boiler Fuel Types
Boiler Furnaces compatible with following types of Fuels
3.1. Boiler Solid Fuels
· Pet Coke
· Rice Husk
3.2. Boiler Liquid Fuel
· LDO (Light Diesel Oil)
· Furnace oil
3.3. Boiler Gaseous Fuels
· PNG can be used to carry out the combustion for a specific purpose.
4. Components of a Boiler Systems
Boiler design is made up of 3 main components–
4.1. Boiler Feedwater System
Water that converts into steam-by-steam boilers system called Feedwater & system that regulates feed water called Feedwater system.
4.1.1. There are two types of feedwater systems in boilers:
· Open feed System
· Closed feed System.
4.1.2. There are two main sources of feed water:
· Condensed steam returned from the process.
· Raw water arranged from outside the boiler’s plant processes.
4.2. Boiler Steam System
Steam System is a kind of main controlling system of the boilers process. Steam Systems are responsible to collect & control all generated steam in the process.
Steam systems send steam generated in the process to the point of use through pipes (piping system). Throughout the process, steam pressure is controlled and regulated with the help of boilers system parts such as valves, steam pressure gauges, etc.
4.3. Boilers Fuel System
Fueling is the heart of the boilers process & fuel system consists of all the necessary components and equipment to feed fuel to generate the required heat. The equipment required in the fuel system depends on the type of fuel used in the system.
5. Boiler Applications
The Boilers have a very wide application in different industries such as Power Sector
· Food Processing Industry
· Sugar Plants
· Thermal Power Plants
6. Key Manufacturer:
· Forbes Marshall
· Thermax India Limited
· Cheema Boilers
· Thermodyne Engineering Systems