Overview of Boiler Classification

1-Classification by use

Power station boiler: used for power generation, most of them are large-capacity, high-parameter boilers, fired in a fire chamber, with high efficiency, and the outlet working fluid is superheated steam.

Industrial boilers: used for industrial production and heating, most of them are low-pressure, low-temperature, small-capacity boilers, most of which are fired in a fire bed, with low thermal efficiency. The outlet working fluid is steam called steam industrial boiler. The outlet working fluid is hot water, which is called a hot water boiler.

Marine boiler locomotive boiler steam injection boiler: It is used for steam injection thermal recovery of heavy oil in oil fields, and the outlet working fluid is generally high-pressure wet steam.

2-Classification by structure

Fire tube boiler: The flue gas flows through the fire tube, which is generally a small-capacity, low-parameter boiler with low thermal efficiency, but simple structure, low water quality requirements, and convenient operation and maintenance.

Water tube boiler: Soda water flows through the tube, which can be made into a small-capacity, low-parameter boiler, or a large-capacity, high-parameter boiler. Power station boilers are generally water-tube boilers, with high thermal efficiency, but also higher requirements for water quality and operation level.

3-Classification by circulation

Natural circulation drum boiler, multiple forced circulation drum boiler, low rate circulation boiler, once-through boiler, compound circulation boiler

4-Classification by boiler outlet working fluid pressure

Low pressure boiler: the general pressure is less than 2.5MPa

Medium pressure boiler: the general pressure is 3.825MPa

High pressure boiler: the general pressure is 9.8MPa

Ultra-high pressure boiler: the general pressure is 13.73MPa

Subcritical pressure boiler: the general pressure is 16.67MPa

Supercritical pressure boiler: the general pressure is 22.13MPa

5-Classification by burning method

Fire bed combustion boiler: mainly used for industrial boilers, including fixed grate furnace, reciprocating grate furnace, etc..

Fire-chamber combustion boiler: mainly used for power station boilers. The boilers that use liquid fuel, gas fuel and pulverized coal are all fire-chamber combustion boilers.

Boiling furnace: The air flow rate sent into the grate is high, so that the large particles of coal are tossed and burned in the fluidized bed above the grate, and the small particles of coal rise with the air and burn.

6-Classification by fuel or energy used

Solid fuel boiler: burning coal and other solid fuels;

Liquid fuel boilers: use liquid fuels such as heavy oil;

Gas fuel boiler: use gas fuel such as natural gas;

Waste heat boiler: use the waste heat of metallurgy, petrochemical and other industries as a heat source;

Atomic energy boiler: a steam generator that uses the heat energy released by the nuclear reactor as a heat source;

Waste heat boiler: a boiler that uses waste, bark, waste liquid and other wastes as fuel;

Other energy boilers: steam generators or water heaters using geothermal, solar and other energy sources.

7-Classification by slag discharge method

Solid state slag discharge boiler, liquid slag discharge boiler

8-Classification by furnace flue gas pressure

Negative pressure boiler: the furnace pressure maintains negative pressure, and there are supply and induced draft fans, which are the main types of coal-fired boilers;

Micro positive pressure boiler: the gauge pressure of the furnace is 2-5KPa, no induced draft fan is required, and it is easy to burn with low oxygen.

9-Classification by drum arrangement

The number of boiler drums is generally one or two, and the drums can be arranged vertically or horizontally. Modern drum-type power station boilers use single-drum type, and industrial boilers use drum or double-drum type.

10-Classification by furnace type

There are many types of boilers, including inverted U-type, tower-type, box-type, T-type, U-type, N-type, L-type, D-type, A-type, etc. Type D and Type A are used for industrial boilers, and other types are generally used for power station boilers.

11-Classification by boiler room type

Boilers can be arranged in the open air, semi-open air, indoor, underground or in the cave. Industrial boilers are generally arranged indoors, and power station boilers are mainly arranged in indoor semi-open air or open air.

12-Classification by boiler factory type

It can be divided into quick-installed boilers, assembled boilers and bulk boilers; small boilers can be quick-installed, and power station boilers are generally assembled or bulk.