Specifications

1.sufficient output
2.high efficiency
3.excellent adaptability for varieties of coal
4.safe and reliable

DHL Type Boiler Introduction

 

In recent years,with the rapid deveplopment of marketing economy , people’s rising living standard,the environmental awareness is also growing. The state advocates to develop environmentally friendly energy-saving products.Our company introduced a single drum horizontal chain grate forced circulation hot water boiler. This type of boiler has been widely used in the country,and is ideal for central heating supply.

The boiler, a single drum horizontal P type forced circulation hot water boiler,adopt tiered coal feeder and trabeated style chain grate combustion equipment. Arrange the membrane wall tubes around and in the center of the furnace,to absorb the radiation heat of high temperature gas in the furnace.Slag screen shall be arranged at the outlet of the furnace,to further absorb heat radiation. In order to fully burn the coal and to ensure combustion efficiency,cover rate of front arch to the grate shall be 25%,the cover rate of rear arch to the grate shall be 57%, to achieve better effect. As the boiler is a little wider,arrange two steel tube type snake tube convection heating surface,after which set two air preheater. Flue gas in the pipe parallel scrub the tube bundle and air cross-flow scrub outside the pipe. The air preheater shall be allocated at the operation platform outside the steel support.The fornace has used the front arch and the rear arch to ensure the high boiler combustion efficiency and the grate heat loads of funace.The grate adopts stepless speed regulation,meeting any regulation of load and not affecting the thermal stability of combustion.

 

Boiler water flow

Feed warer →Rear water cooled wall of furnace→Two rows of snake tube heating surface→Two sides of water cooled wall of furnace→water wall panel→Front water cooled wall of furnace→Drum→Effluent.

DHL boiler characteristics:

1.Use mature Π-type arrangement, compact boiler layout, small size, less space requiremnet, reducing investment in the boiler room.

2.The arrangement of boiler heating surface has fully used boiler room.Around the furnace set the membrane wall,and connecting tubes arranged outside the boiler body. Convection heating surface uses snake tube structure.Inlet and outlet headers are set outside of the boiler, easy for installation and maintenance, less fouling, convienient for cleaning.

3.Drum arranged above the furnace, and connected headers with power failure protection pipe,thus could protect themselves better.

4.Useing forced circulation,The water velocity of boiler is a little high,the rising water speed between 1.0-1.15m / s and the decline water velocity between 1.1-2.0m / s. The use of drum, increase the boiler water capacity to protect the safe operation of the boiler.

5.Boiler adopts full shield structure,and the furnace using the whole membrane wall, sealing, and less air leakage,thus heat loss due to exhaust gas is much reduced, boiler thermal efficiency is improved,and at the same time reducing the boiler flue gas emissions and boiler fan power consumption

6.The boiler design a larger furnace, making the gas in the furnace to stay longer, and fully combusting the fly ash and combustible gases, improving combustion efficiency.Moreover,the rising speed of gas in the furnace is low, greatly reduced the carrying fly ash,and original concentration of boiler emissions.

7.This boiler arch adopts scientific and technological achievements of national "Plan" research project of Xi'an Jiaotong University (using rectangular furnace arch in the outlet of the rear arch), to ensure combustion of low-quality coal, and to improve boiler coal’s adaptability.

8.Boiler grate shall be trabeated style,to improve operation safety. Meanwhile grate-structured and well-tuned wind performance ensure complete combustion,and much reduced the mechanical loss of incomplete combustion.

9. Power failure protection

The upper part of the boiler set drum, increasing the volume of the boiler water,meeting the cooling needs of boiler water wall after power failure.

In avoid of the sudded waterhammer or even overheating of tubes while coming across power failure in operation,take the following measures:

There are steel pipes connecting with boiler drum in each circuit of water wall.Once power failure,the forced circulation shall be changed to natural circulation.

The tubes of water wall in the furnace are with a diameter of φ60mm and φ73mm.After a sudden power failure, a single tube can be formed of its own natural micro-circulation, so that the wall shall not be overheated in a certain period of time.

When power failure,according to the pressure of hot water,properly open some vent values.Meanwhile the pressure of hot water shall not be over 0.5 Mpa in boiler system.Under this pressure,the saturated temperature of hot water shall not be over 150°C,which allows only a small amount of boiler water become steam.As the drum is at the top of boiler, there are still water in other water pipes,which makes it’s safe in sudden power failure.

 

Name		Specification of DHL Series Water Tube Boiler
		DHL46-1.6/150/90-AII	DHL58-1.6/150/90-AII	DHL70-1.6/150/90-AII	DHL91-1.6/150/90-AII
(MW) Rated Heat Supply Quantity		46	58	70	91
(Mpa) Rated Work pressure		1.6	1.6	1.6	1.6
(°C) Water Supply Temp		150	150	150	150
(°C) Return Water Temp		90	90	90	90
Heating Surface	Boiler Proper	2328	2901	3625	4637
Effective area of great		58.5	71.6	87.7	116
Applicable Fuel	Design coal	AII	AII	AII	AII
	(KJ/kg) Applied Basis Low Heating Value	17700	17700	17700	17700
(Kg/h) Fuel Consumption		11265	14204	17142	22285
(%) Heat Efficiency		83	83	83	83
(m) Max Transportation Size(MM)		9520×2000×1700	11100×2000×1700	12700×2000×1700	14400×2250×1900
Max Dimension of Boiler Proper After Installation (MM)		15623×12030×14273	16168×13470×14873	16050×16000×15500	18358×17280×16200
Forced draft fan	Model	G4-73-12 14D	G4-73-12 16D	G4-73-12 16D	G4-73-12 18D
	(m3/h) Air Volume	79944	108270	130390	169910
	(pa) Air pressure	2716	3653	3391	4518
	(r.p.m) Rotaional speed	960	960	960	960
	(kw) Power	90	185	185	315
Induced draft fan	Model	Y4-73-11 20D	Y4-73-11 22D	Y4-73-11 22D	Y4-73-11 22D
	(m3/h) Wind force	167130	214000	244670	320610
	(pa) Wind pressure	3598	3545	4500	2392
	(r.p.m) Rotaional speed	960	960	960	960
	(kw) Power	355	355	500	630
Govenor	Model	GL-80P	GL-80P	GL-100P	GL-100P
	(kw) Power	5	7.5	7.5	7.5

 The terminal parameters shall be as per blueprint paper,and the model and parameters of forced draft fan and ID fan shall be as per the design of design institute.