Single-pressure self-deoxidizing waste heat boiler for third-section and fourth-section waste heat recovery of sintering circular cooler

Abstract

The utility model relates to a single-pressure self-deoxidizing waste heat boiler for recycling waste heat of third and fourth sections of a sintering circular cooler, which is characterized in that a water preheater and an evaporator are sequentially arranged in a steel frame from bottom to top, the top of the evaporator is communicated with an inlet flue, the bottom of the water preheater is communicated with a dust collector, and the dust collector is communicated with an outlet flue; an evaporator inlet header is arranged at the inlet end of the evaporator, an evaporator outlet header is arranged at the outlet end of the evaporator, the water preheater is communicated with the water feeding pump through the water preheater inlet header and further communicated with the deoxidizing head through the water preheater outlet header, and the deoxidizing head is communicated with the evaporator inlet header through a descending pipe. The evaporator outlet header is communicated with the steam pocket through an ascending pipe, the steam pocket is communicated with the deoxygenization head through a deoxygenization heating steam pipe, and the deoxygenization head is communicated with a user steam pipe network through a saturated steam pipe. The vertical arrangement is adopted, the occupied space is saved, meanwhile, ash discharge of the boiler is facilitated, and a natural circulation system is high in reliability, good in stability and convenient to operate and maintain.

Description

Technical Field

[0001] The utility model relates to a single-pressure self-deoxidizing waste heat boiler used for recovering the third and fourth stage waste heat of a sintering ring cooler. Background Art

[0002] At present, one of the methods for utilizing the waste heat of the flue gas from the third and fourth stages of the ring cooler on the market is: the 4# blower takes air from the environment and sends it to the fourth stage of the ring cooler. The outlet air enters the inlet of the 3# blower and is sent to the third stage of the ring cooler after being pressurized. The outlet air from the third stage passes through the dust collector and the heat recovery fan and enters the sintering machine as combustion air. The disadvantage is that due to the limited heat used for low-temperature hot air ignition, most of the hot flue gas from the third stage of the ring cooler is discharged in vain, resulting in heat loss, resulting in low waste heat utilization rate of the third and fourth stages of the ring cooler. In addition, as users modify the sealing of the ring cooler, the flue gas temperature of the third stage of the ring cooler has increased compared with the past, and the flue gas temperature is about 300℃, with a maximum of 340℃, and the waste heat utilization value is relatively large.

[0003] Many steel plant boilers were installed before the water seal modification of the annular cooler. With the subsequent water seal modification of the annular cooler, the air leakage rate of the annular cooler was greatly reduced. The flue gas temperatures of the first and second stages of the annular cooler were much higher than the original design. The use capacity of the original annular cooling waste heat boiler has reached its limit and may even be overloaded. Therefore, it is necessary to add a small waste heat boiler next to the original annular cooling waste heat boiler. Utility Model Content

[0004] The utility model provides a single-pressure self-deoxidizing waste heat boiler for recovering waste heat from the third and fourth stages of a sintering ring cooler. The vertical arrangement saves floor space and facilitates boiler ash discharge. The natural circulation system has strong reliability, good stability, and is easy to operate and maintain.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A single-pressure self-deoxidizing waste heat boiler for recovering waste heat from the third and fourth stages of a sintering ring cooler, characterized in that a water preheater and an evaporator are arranged in sequence from bottom to top in a steel frame, the top of the evaporator is connected to an inlet flue, the bottom of the water preheater is connected to an ash collector, the ash collector is connected to an outlet flue, an evaporator inlet header is arranged at the inlet end of the evaporator, and an evaporator outlet header is arranged at the outlet end of the evaporator;

[0007] The water preheater is connected to the feed water pump through the water preheater inlet header for heating the water supply. The water preheater is also connected to the deaerator head through the water preheater outlet header for deaerating the water supply. The deaerator head is connected to the evaporator inlet header through the downcomer to supply the deaerated water into the evaporator for heating. The evaporator outlet header is connected to the steam drum through the riser to supply the steam-water mixture in the evaporator into the steam drum for steam-water separation. The steam drum is connected to the deaerator head through the deaeration heating steam pipe for heat exchange deaeration. The deaerator head is connected to the user steam pipe network through the saturated steam pipe.

[0008] In the single-pressure self-deaerating waste heat boiler for the third and fourth sections of the sintering ring cooler, a flap valve is arranged at the bottom of the ash collector to discharge the accumulated ash from the ash collector.

[0009] In the single-pressure self-deaerating waste heat boiler for the third and fourth sections of the sintering ring cooler, a platform ladder is arranged on the steel frame for the operation of manholes and valve instruments.

[0010] The beneficial effects of the present utility model are as follows: The waste heat boiler adopts a vertical layout and a single-inlet structure. The flue gas enters from the top of the boiler and passes through the evaporator and the water preheater in sequence and then discharges from the bottom. The vertical layout saves floor space and is convenient for ash discharge of the boiler. The water circulation mode of the boiler is natural circulation. The natural circulation system has the advantages of strong reliability, good stability, convenient operation and maintenance, etc., and saves the investment, operation and maintenance costs of the circulation pump for forced circulation. The single-pressure self-deaerating system is adopted. The deaerator head is supported on the inlet water pipe seat above the steam drum and is directly connected to the steam drum. A part of the saturated steam led out from the steam drum enters the deaerator head to heat the demineralized water for deaeration, and the other part enters the user steam pipe network. The self-deaerating structure integrates the deaerator head and the steam drum, reduces the floor space of the entire boiler, saves the consumption of the boiler steel frame, reduces the investment of users, and is very beneficial for users with compact on-site space. At the same time, the self-deaerating structure does not require an external heat source, greatly reducing the operation cost of the deaerator. Description of the Drawings

[0011] Figure 1 It is a structural diagram of a single-pressure self-deaerating waste heat boiler for the third and fourth sections of the sintering ring cooler.

[0012] Figure 2 It is a side view structural diagram of a single-pressure self-deaerating waste heat boiler for the third and fourth sections of the sintering ring cooler.

[0013] Description of the reference numerals: 1 - inlet flue; 2 - evaporator; 3 - water preheater; 4 - outlet flue; 5 - flap valve; 6 - feed water pump; 7 - water preheater inlet header; 8 - water preheater outlet header; 9 - deaerator head; 10 - downcomer; 11 - evaporator inlet header; 12 - evaporator outlet header; 13 - riser tube; 14 - steam drum; 15 - deaeration heating steam pipe; 16 - saturated steam pipe; 17 - steel frame; 18 - platform and ladder; 19 - ash collector. Detailed implementation mode

[0014] As Figures 1 to 2 Shown is a single-pressure self-deaerating waste heat boiler for the waste heat recovery of the third and fourth sections of a sintering ring cooler, which is characterized in that: a platform and ladder 18 is arranged on the steel frame 17 for the operation of manholes and valve instruments. The water preheater 3 and the evaporator 2 are sequentially arranged from bottom to top in the steel frame 17. The top of the evaporator 2 is communicated with the inlet flue 1. The bottom of the water preheater 3 is communicated with the ash collector 19. The ash collector 19 is communicated with the outlet flue 4. A flap valve 5 is arranged at the bottom of the ash collector 19 for discharging the accumulated ash from the ash collector 19. An evaporator inlet header 11 is arranged at the inlet end of the evaporator 2, and an evaporator outlet header 12 is arranged at the outlet end of the evaporator 2.

[0015] The water preheater 3 is communicated with the feed water pump 6 through the water preheater inlet header 7 for heating the water supply. The water preheater 3 is also communicated with the deaerator head 9 through the water preheater outlet header 8 for deaerating the water supply. The deaerator head 9 is communicated with the evaporator inlet header 11 through the downcomer 10 for sending the deaerated water into the evaporator 2 for heating. The evaporator outlet header 12 is communicated with the steam drum 14 through the riser tube 13 for sending the steam-water mixture in the evaporator 2 into the steam drum 14 for steam-water separation. The steam drum 14 is communicated with the deaerator head 9 through the deaeration heating steam pipe 15 for heat exchange and deaeration. The deaerator head 9 is communicated with the user steam pipe network through the saturated steam pipe 16.

[0016] In the embodiment, the flue gas passes through the inlet flue 1 and successively flows through the evaporator 2 and the water preheater 3, and is discharged through the outlet flue 4. The flue gas respectively exchanges heat with the feed water in the tube bundles of the evaporator 2 and the water preheater 3. The feed water pump 6 is started to boost the pressure of the feed water and the feed water flows through the water preheater inlet header 7 and is sent into the water preheater 3 for heat exchange. After being heated, the feed water flows into the deaerator head 9 through the water preheater outlet header 8 for deaeration. The deaerated feed water flows into the evaporator inlet header 11 through the downcomer 10 and enters the evaporator 2 for heat exchange. After heat exchange, the feed water becomes a steam-water mixture and flows out of the evaporator outlet header 12, and enters the steam drum 14 through the riser 13 for steam-water separation and becomes saturated steam. A part of the saturated steam in the steam drum 14 enters the deaerator head 9 through the deaeration heating steam pipe 15 to exchange heat with the feed water in the deaerator head 9 for deaeration. The remaining part of the saturated steam in the steam drum 14 is sent into the user steam pipe network through the saturated steam pipe 16 for heat supply to users.

[0017] The above description is illustrative rather than restrictive to the present utility model. Those of ordinary skill in the art understand that without departing from the spirit and scope defined by the claims, many modifications, variations or equivalents can be made, but all will fall within the protection scope of the present utility model.

Claims

1. A single-pressure self-deoxidizing waste heat boiler for recovering waste heat from the third and fourth stages of a sintering ring cooler, characterized in that: A water preheater (3) and an evaporator (2) are arranged in sequence from bottom to top in the steel frame (17); the top of the evaporator (2) is connected to the inlet flue (1); the bottom of the water preheater (3) is connected to the ash collector (19); the ash collector (19) is connected to the outlet flue (4); an evaporator inlet header (11) is arranged at the inlet end of the evaporator (2); and an evaporator outlet header (12) is arranged at the outlet end of the evaporator (2); The water preheater (3) is connected to the water supply pump (6) through the water preheater inlet header (7) to heat the water supply. The water preheater (3) is also connected to the deaerator header (9) through the water preheater outlet header (8) to deoxygenate the water supply. The deaerator header (9) is connected to the evaporator inlet header (11) through the downcomer (10) to feed the deoxygenated water into the evaporator (2) for heating. The evaporator outlet header (12) is connected to the steam drum (14) through the riser (13) to feed the steam-water mixture in the evaporator (2) into the steam drum (14) for steam-water separation. The steam drum (14) is connected to the deaerator header (9) through the deaerator heating steam pipe (15) to provide heat exchange and deoxygenation. The deaerator header (9) is connected to the user's steam network through the saturated steam pipe (16).

2. A single-pressure self-deoxidizing waste heat boiler for recovering waste heat from the third and fourth stages of a sintering ring cooler as claimed in claim 1, characterized in that: A flap valve (5) is provided at the bottom of the ash collector (19) to allow accumulated ash to be discharged from the ash collector (19).

3. A single-pressure self-deoxidizing waste heat boiler for recovering waste heat from the third and fourth stages of a sintering ring cooler as claimed in claim 1, characterized in that: A platform ladder (18) is provided on the steel frame (17) for operating the manhole and valve instruments.

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