First, the fire tube hot water boiler
There are two types of boilers of this type, vertical and horizontal, which are suitable for oil and gas. Parameter range of vertical flue gas-fired hot water boiler;
Rated thermal power ≤2.8MW
Normal rated pressure, 1.0MPa
Supply and return water temperature 95℃/70℃
WNS horizontal internal combustion hot water boiler series product parameter range:
The rated thermal power is 0.35-7.6 MW.
The rated pressure is 0.7MPa；; 1.0 MPa
Supply and return water temperature 95℃/70℃; 1 15℃/70℃
Second, the water-fire tube hot water boiler
This kind of boiler is mainly composed of horizontal external combustion tempering tube boiler and water wall tube heating surface, which is relatively compact in structure and can leave the factory at any time, so it is called "quick-loading" boiler. This type of hot water boiler is widely used in China, with the largest number. Its models are: KZL, KZG, KZW, KZZ and other products. Its working parameter range:
The rated power is 0.35-14mw;
The rated pressure is 0.7-1.25mpa;
Supply and return water temperature 95℃/70℃; 1 15℃/70℃; 130℃/70℃
Three, no drum riser hot water boiler
This kind of boiler is generally forced circulation mode, with vertical tubes arranged in the furnace and pipe racks on the convection heating surface. For coal-fired hot water boiler, its power is ≤ 7.0 MW; Oil-fired and gas-fired hot water boiler, with power ≤ 14MW. This hot water boiler is compact in structure, convenient to manufacture and saves steel. At present, this type is often used in small-capacity hot water boilers. Combustion modes include reciprocating grate, chain grate and vibrating grate.
Because the layout of tubular convection heating surface is limited by the height direction, this type is not suitable for large-capacity hot water boilers.
The product series parameters of this type of boiler are: 0.2MW, 2.8MW, 4.2MW, 7.0MW and other coal-fired hot water boilers. Oil-fired and gas-fired boilers include 14MW hot water boilers.
Four, forced circulation hot water boiler drum elbow
In the past, water heaters that changed from steam to water, such as SZPL 0- 1.3 steam boilers or SHL 20- 13 steam boilers, were changed to hot water boilers and forced circulation. Usually, water is supplied from the lower header and the lower drum, and the downcomer is throttled, so that the water rises at a certain flow rate on the heating surface and is discharged from the upper drum.
The designed product series of forced circulation hot water boilers are: QXL 4.2-0.7-95/70 1A, qxl7.0-1.0-15/701a, qxll4-1.
Verb (abbreviation of verb) Vertical water pipe natural circulation hot water boiler with drum
This boiler is characterized in that backwater enters from the upper drum and is sent to the downcomer through the water distribution device arranged in the drum, and the water in the water wall tube or the ascending furnace tube is introduced into the upper drum after heating and sent out with hot water. This type of boilers are: SZW, SHW, SHL, DHL, DHD, etc. Its parameter range:
The rated thermal power is 0.35-29 MW.
The rated pressure is 0.7 ~ 2.45 MPa.
Supply and return water temperature 95℃/70℃; 1 15℃/70℃; 130℃/70℃; 150℃/90℃
Six, steam-water dual-purpose furnace with steam drum
This kind of boiler is characterized by supplying both steam and hot water, and it is high temperature water. Because part of oxygen can be removed when steam is supplied, the oxygen corrosion of the boiler is reduced compared with that of the ordinary hot water boiler. The boiler has a small capacity, about 2.8-4.2 MW, and the pressure is below ≤ 1.3MPa.
The outlet water temperature of this dual-purpose boiler is close to the saturation temperature, and the mixed water cooling measures must be taken before entering the pipe network system, so the operation is more complicated than that of ordinary hot water boilers.
If it is a power plant boiler, it is a boiler used by power plants to generate electricity. Generally, the capacity is large, and now the main engine is 300MW. There are two main types of utility boilers: pulverized coal boilers and circulating fluidized bed boilers. These two types of boilers are the main types used in power stations at present. The biggest difference between fluidized bed furnace and pulverized coal furnace is liquid and pulverized coal.
In addition, large units can also be divided into tower type, box type and π type (π type can also be divided into front and rear wall hedge, W furnace, four corners tangent circle and front wall arrangement according to burner arrangement).
Anyway, these things are complicated.