Boiler classifications and types
BOILER DEFINITION
A boiler is a machine that works by converting water into steam, hence boiler is also known as
steam generator.
The steam from the boiler is used in many places. If we talk about the use of this steam, then it is used in the most power-generating station where electricity is generated.
Apart from this, steam is needed in many other industries like the textile industry, sugar mill, chemical industry, etc. So within all these industries you also get to see boilers.
Use of steam from the Boiler
Steam is used for different jobs everywhere. Let me tell you some main uses, with the help of which you will get an idea.
*For rotating turbines in power plant
* To heat water
*For air heating in AHU
TYPES OF BOILERS
The boiler is divided in different ways according to its need and design.
* Based on Tube Container
*Position of Furnace
*According to Boiler Position
* According to the use
*According to the water and steam circulation
*According to the Fuel Uses
*According to the pressure developed
*Based on the fuel combustion system
*Based on fuel feeding
*Based on Tube Contain boilers
The boiler is divided into two parts, depending on the tube used in the boiler.
A) Fire Tube Boiler - In a fire tube boiler, there is a fire inside the tube and there is water around the tube, hence it is called a fire tube boiler.
Fire tube boilers are mostly installed
at the place where we need flame pressure steam.
B) Water Tube Boiler- In this boiler, there is water inside the tube, and the rest is fire. Due to this we get more steam from this boiler.
Where we need high-pressure steam, we use a water tube boiler.
Position of Furnace Boilers
A) Externally Fired Boiler - In this type of boiler, we give fire outside the furnace to the boiler.
Meaning, in this boiler, we keep the fire in a separate section, meaning outside the furnace, that is why we call it an externally Fired Boiler.
B) Internally Fired Boiler- This boiler is exactly opposite to the externally Fired Boiler. When we put fire inside the furnace, it produces heat inside it, it is called Internally Fired Boiler.
FBC boiler, pfbc boiler Both of these are examples of Internally Fired Boiler, in which it is done inside the fiery furnace.
According to Boiler Position
In addition, the boiler is also divided according to its position. The boiler position in this means the position of the axis of the boiler shell.
In this way, the boiler is divided into three parts.
*Vertical Boiler
*Horizontal boiler
*Inclined boiler
According to the use
Stationary Boiler- This boiler is fixed in one place, it cannot change its position. The stationary Boiler includes all the big boilers that are made in the company's building.
If we talk about its example, then FBC Boiler, CFBC Boiler, PFBC Boiler are also examples of Stationary Boiler, all these boilers are fixed in one place.
Portable Boiler- A portable boiler is also called a mobile boiler. Marine Boiler is an example of this type of boiler, it is used in boiler water ships.
Thus Marine Boiler being in the ship changes its position from one place to another. So the same type of boiler is called Portable Boiler and Mobile Boiler.
According to the water and steam circulation
In addition, the boiler is also divided according to how steam and water are circulating inside the boiler.
Natural Circulation Boiler - Inside it comes all those boilers, inside which the circulation of water and steam is natural. We never apply any type of force in this boiler.
In this boiler steam and water flow up and down naturally.
Forced Circulation Boiler - Also when we take the help of a force to bring water and steam from one place to another, it is called Forced Circulation Boiler.
You must have seen this process many times, that we are taking the help of a pump to bring water from one place to another in the boiler. Similarly, any boiler in which we apply force to make water and steam flow is called Forced Circulation Boiler.
The forced Circulation Boiler is also divided into two parts.
*Controlled
*Once through
According to the Fuel Uses
The boiler is also divided according to fuel usage. We use Fuel to convert water into steam by generating heat. Different types of fuel are used to generate heat in all boilers, which are as follows.
*Coal Fired Boiler
*Oil-fired boiler
*Gas-fired boiler
*Electrically Heated Boiler
*Nuclear heat boiler
*Solar Energy boiler
*Hot waste gases boiler
According to the pressure developed
After this, we also distribute the boiler according to its pressure.
* Low-Pressure Boiler - If the pressure of this boiler is less than 80 bar, we call it a Low-Pressure Boiler. Many times we call boilers less than 40 bar flame pressure boilers, and boilers from 40 bar to 80 bar are called medium pressure boilers.
* High-Pressure Boiler- The boiler that has a pressure above 80 bar is called a high-pressure boiler. The high-pressure boiler is divided into two ways.
*Subcritical Boiler - A boiler whose pressure is between 80 bar to 221 bar is called a Subcritical high-pressure boiler.
*Super Critical Boiler - And the boiler which has a pressure of more than 221 bar is called a Super Critical high-pressure boiler.
Based on the fuel combustion system
* Suspension Combustion Boiler - Suspension boilers include those boilers in which fuel is burnt in the air, where fuel is burned in the middle of the furnace. Example-PF Boiler
*Bed combustion boiler- The boiler in which fuel combustion is used on the combustion bed is called a bed combustion boiler.
There are two types of bed combustion boilers.
*Chain Gate Stoker Boiler
*Fluidized Bed Boiler
Based on fuel feeding
The boiler is also distributed according to fuel feeding. Fuel feeding means how we are sending fuel to the boiler. Here we feed fuel in boilers in two ways.
1. Above Bed- When fuel is fed from above the bed, it is called the above bed fuel-feeding boiler. Examples- Stoker Bed, CFBC boiler
2. Under Bed - But if we feed fuel from under the bed, then it is called the Under Bed fuel feeding boiler. Example-AFBC boiler
So there are some of the main types, the way the boiler is divided. By the way, apart from this, we can also divide the boiler in many ways.
Like - according to the tube, according to the drum, according to the draft, etc.