structure
Overall structure
The overall structure of the boiler includes two parts: the boiler body (drum), auxiliary equipment and safety device. The main components of the boiler, such as furnace, drum, burner, water wall, superheater, economizer, air preheater, frame and furnace wall, constitute the core part of steam production, which is called the boiler body. The two most important parts of the boiler body are the furnace and the drum.
Internal Structure Chart of Rice Husk-fired Steam Boiler
Furnace, also known as combustion chamber, is the space for fuel combustion. The furnace in which solid fuel is placed on the grate and burned in the firebed is called the layer burner, also known as the firebed furnace; the furnace in which liquid, gas or ground solid fuel is injected into the fireroom is called the chamber burner, also known as the chamber furnace; the air holds up the coal particles to make them burn in a boiling state and is suitable for burning inferior fuels. It is called fluidized bed furnace, also known as fluidized bed furnace. Cylindrical furnace, which uses air flow to make coal particles rotate at high speed and burn intensely, is called cyclone furnace.
Furnace design
Furnace design needs to fully consider the characteristics of using fuel. Each boiler shall use as much fuel as possible as possible as originally designed. The economy and reliability of boiler operation may be reduced when the fuel with different characteristics is burned.
Pot
It is a cylindrical vessel that receives water from economizer, connects circulation circuit and delivers saturated steam to superheater in natural circulation and multiple forced circulation boilers. The cylinder is made of high quality thick steel plate and is one of the most important parts of the boiler.
Main functions of pot drum
The main function of pot drum is to store water, separate steam from water, remove brine and mud from pot water in operation, and avoid pot water containing high concentration of salt and impurities entering superheater and steam turbine with steam.
Internal device of pot drum
Including steam-water separation and steam cleaning devices, water distribution pipes, sewage and pharmaceutical equipment. The function of the steam-water separator is to separate the saturated vapor from the water wall and minimize the small droplets carried in the vapor. The baffles and slot baffles are commonly used as coarse separation elements in medium and low pressure boilers. In addition to various types of cyclone separators, the boilers above medium pressure are further separated by louvers, wire mesh or steam equalizing plates. The drum is also equipped with water level gauges, safety valves and other monitoring and protection facilities.
Design considerations
In order to check performance and improve design, boilers often have to undergo heat balance tests. The method of calculating boiler thermal efficiency directly from the effective use of energy is called positive equilibrium, and the method of calculating boiler thermal efficiency from various heat losses is called reverse equilibrium. When considering the actual benefit of the boiler room, not only the thermal efficiency of the boiler, but also the energy consumed by the auxiliary machine of the boiler should be taken into account.
LSS Vertical Oil (Gas) Steam Boiler
When the fuel of unit mass or unit volume is completely burned, the air demand calculated by chemical reaction is called theoretical air quantity. In order to provide more opportunities for fuel to burn in the furnace in contact with oxygen, the actual amount of air fed into the furnace is always greater than the theoretical amount of air. Although more air can reduce the heat loss of incomplete combustion, the heat loss of exhaust gas will increase, which will also aggravate the corrosion of sulfur oxides and the formation of nitrogen oxides. Therefore, we should try to improve the combustion technology and try to make the combustion in the furnace complete with the minimum excess air coefficient.
