CN212618206U

CN212618206U - Electric furnace exhaust-heat boiler

Info

Publication number: CN212618206U
Application number: CN202021048944.3U
Authority: CN
Inventors: 魏海军; 古晓峰; 肖勇; 范超前; 赵坤; 黄晓琼; 郭斌; 徐慧; 钟永辉; 曾吉辉
Original assignee: Sichuan Crun Power Equipment Co ltd
Current assignee: Sichuan Crun Power Equipment Co ltd
Priority date: 2020-06-09
Filing date: 2020-06-09
Publication date: 2021-02-26
Anticipated expiration: 2030-06-09

Abstract

The invention discloses an electric furnace waste heat boiler which is horizontal and comprises an inlet cooling smoke hood, an evaporator, an economizer, an outlet flue and an ash conveying system; the evaporator is arranged in multiple stages, and the evaporator is integrally suspended; the inlet end of the evaporator is provided with an inlet cooling smoke hood, and the outlet end of the evaporator is sequentially provided with a coal economizer and an outlet flue; the top of the evaporator is provided with a steam drum, and the lower part of the evaporator is provided with an ash conveying system. The invention adopts a full-suspension structure, and reasonably arranges the expansion center, so that the boiler has a safer and more reliable structure under the action of alternating stress. The radiation baffle plates are arranged at the positions with high local thermal load strength, so that the thermal load strength of the sealing connection part is reduced, and the connection reliability is improved. The heating surfaces at all levels are highly integrated, modularized and standardized, and convenience is brought to logistics transportation and construction site assembly. The settled ash is quickly cooled by using the water-cooled ash bucket and the internal ash cooling pipe, so that the ash deposition of the boiler is effectively reduced, the requirement of an ash conveying system is better met, and valuable metals contained in the ash are recovered.

Description

Electric furnace exhaust-heat boiler

Technical Field

The invention relates to the technical field of electric furnace steelmaking waste heat utilization, in particular to an electric furnace waste heat boiler.

Background

The electric arc furnace steelmaking is a steelmaking process using electricity as an energy source, belongs to short-process steelmaking, and mainly uses scrap steel as a raw material. A large amount of high-temperature dust-containing flue gas is generated in the steelmaking process, and the sensible heat of the flue gas accounts for more than 10 percent of the total energy consumption of electric furnace steelmaking. At present, the cooling mode for the flue gas is mainly a water cooling mode at home, a large amount of electric energy and water can be consumed in the traditional cooling mode, and heat of a large amount of high-temperature flue gas is discharged into the atmosphere, so that not only is the energy wasted, but also adverse effects are caused to the environment.

The electric furnace flue gas characteristics: the temperature of the flue gas entering the waste heat boiler is periodically changed within the range of 130-850 ℃.

1. The traditional electric furnace waste heat boiler can not meet the characteristic that the working condition of electric furnace steelmaking periodically changes.

2. The traditional electric furnace waste heat boiler cannot solve the problems of large heat load change, high heat strength and the like under alternating working conditions.

3. The traditional electric furnace waste heat boiler has short service life, unstable heat exchange performance, serious dust deposition, limited boiler expansion, frequent tube explosion and the like.

4. Under the alternating working condition of electric furnace steelmaking, the water level of a steam drum of the traditional electric furnace waste heat boiler can fluctuate violently, so that the boiler cannot run safely and normally.

5. The traditional electric furnace waste heat boiler has the defects that the ash discharging temperature at the high-temperature section is too high, the ash cannot be effectively cooled, and the heating surface and the ash discharging system are easy to accumulate and block.

Disclosure of Invention

In order to overcome the technical defects, the invention aims to provide the horizontal electric furnace waste heat boiler which can improve the safety and the reliability of the structure of the boiler under the action of alternating stress, effectively reduce the dust deposition of the boiler and recover the valuable metals contained in the dust.

In order to achieve the purpose, the invention is realized by the following technical scheme:

the technical scheme is that the electric furnace waste heat boiler is horizontal and comprises an inlet cooling smoke hood, an evaporator, an economizer, an outlet flue and an ash conveying system; the evaporator is arranged in multiple stages, and the evaporator is integrally suspended; the inlet end of the evaporator is provided with an inlet cooling smoke hood, and the outlet end of the evaporator is sequentially provided with a coal economizer and an outlet flue; the top of the evaporator is provided with a steam drum, and the lower part of the evaporator is provided with an ash conveying system.

Further preferably, the evaporator comprises evaporator I, evaporator II, evaporator III and evaporator IV.

Preferably, shock wave soot blowers are arranged in the evaporators at all levels; the bottoms of the evaporator I, the evaporator II and the evaporator III are respectively provided with a water-cooled ash hopper connected with an ash conveying system; the bottom of the evaporator IV and the bottom of the economizer are provided with steel ash hoppers connected with the ash conveying system, so that the ash deposition of the boiler is effectively reduced, the requirement of the ash conveying system is better met, and valuable metals contained in the ash are recovered.

Further preferably, heating surface modules are integrated in the evaporators of all stages; the heating surface module is connected with the steam drum through an ascending pipe and a descending pipe; the heating surface modules in the evaporator I, the evaporator II and the evaporator III comprise membrane walls at the periphery, a light pipe heating surface in the middle and a cold ash pipe at the lower part; the water-cooled ash bucket comprises an ash cooling pipe at the lower part and a part of membrane wall; the heating surface module in the evaporator IV comprises a membrane wall at the periphery and a light pipe heating surface at the middle part, so that the logistics transportation and the construction site assembly are facilitated.

Further preferably, a radiation stop block is arranged between adjacent headers at the top of the heating surface of the light pipe, so that the heat load strength of the sealing connection part is reduced, and the connection reliability is improved.

Further preferably, evaporators at all levels are suspended on a large plate beam of a boiler steel frame through hanging devices, the problem that expansion of a traditional electric furnace waste heat boiler is limited is solved, and the problem that the service life of the traditional electric furnace waste heat boiler is short due to large heat load change and high heat strength under alternating working conditions is solved, so that the boiler is safer and more reliable in structure under the action of alternating stress.

More preferably, the membrane wall is reinforced with rigid beams.

Further preferably, the steam pocket is arranged on the steel frame large plate girder.

Further preferably, the water volume of the steam drum is not less than 1.2 times of the maximum evaporation capacity of the boiler, so that the safe operation of the boiler is ensured.

The invention has the beneficial effects that:

the invention adopts a full-suspension type electric furnace waste heat boiler structure, and an expansion center is arranged at a reasonable position, so that the problem that the expansion of the traditional electric furnace waste heat boiler is limited is solved from the boiler structure, and the problem that the service life of the traditional electric furnace waste heat boiler is short due to large heat load change and high heat strength under alternating working conditions is solved, so that the boiler is safer and more reliable in structure under the action of alternating stress.

The problem of violent fluctuation of water level of the traditional electric furnace waste heat boiler is solved.

The radiation baffle plates are arranged at the positions with high local thermal load strength, so that the thermal load strength of the sealing connection part is reduced, and the connection reliability is improved.

The heating surfaces at all levels are highly integrated, modularized and standardized, and convenience is brought to logistics transportation and construction site assembly.

The settled ash is quickly cooled by using the water-cooled ash bucket and the internal ash cooling pipe, so that the ash deposition of the boiler is effectively reduced, the requirement of an ash conveying system is better met, and valuable metals contained in the ash are recovered.

The top of the boiler is provided with a steam pocket with large water volume, so that the safe operation of the boiler is ensured.

Drawings

The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a schematic diagram of the main structure of the present invention;

FIG. 2 is a schematic view of the structure of a heated surface module according to the present invention.

FIG. 3 is a schematic diagram of the structure of a single tube in the heated surface of the light pipe of the present invention.

FIG. 4 is a schematic view showing the construction of the soot tube of the present invention.

Fig. 5 is a schematic view of the arrangement of the radiation blocks on the header of the present invention.

The labels in the figure are:

the system comprises an inlet cooling smoke hood 1, an evaporator I2, an evaporator II3, an evaporator III4, an evaporator IV5, an economizer 6, an outlet flue 7, a steam pocket 8, an ascending pipe 9, a descending pipe 10, a hanging device 11, a steel frame 12, a rigid beam 13, an ash conveying system 14, a shock wave soot blower 15, a steel ash hopper 16, a water-cooled ash hopper 17, a cold ash pipe 18, a membrane wall 19, a light pipe heating surface 20, a radiation stop block 21, a connecting folded plate 22 and a collection box 23.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In the embodiment, as shown in fig. 1 to 5, the invention is an electric furnace waste heat boiler, which is horizontal and comprises an inlet cooling smoke hood 1, an evaporator, an economizer 6, an outlet flue 7 and an ash conveying system 14; the evaporator is arranged in multiple stages, and the evaporator is integrally suspended; the inlet end of the evaporator is provided with an inlet cooling smoke hood 1, and the outlet end of the evaporator is sequentially provided with a coal economizer 6 and an outlet flue 7; the top of the evaporator is provided with a steam drum 8, and the lower part is provided with an ash conveying system 14.

The evaporator comprises evaporator I2, evaporator II3, evaporator III4 and evaporator IV 5.

Shock wave soot blowers 15 are arranged in each stage of evaporator; the bottoms of the evaporator I2, the evaporator II3 and the evaporator III4 are respectively provided with a water-cooled ash hopper 17 connected with the ash conveying system 14; the evaporator IV5 and the bottom of the economizer 6 are provided with a steel ash hopper 16 connected with an ash conveying system 14.

Heating surface modules are integrated in the evaporators at all levels; the heating surface module is connected with a steam drum 8 through an ascending pipe 9 and a descending pipe 10; the heating surface modules in the evaporator I2, the evaporator II3 and the evaporator III4 comprise membrane walls 19 on the periphery, a light pipe heating surface 20 in the middle and a cold ash pipe 18 on the lower part; the water-cooled ash bucket 17 comprises a lower ash cooling pipe 18 and a partial membrane wall 19; the heating surface module in the evaporator IV5 comprises a membrane wall 19 at the periphery and a light pipe heating surface 20 at the middle part.

Radiation stops 21 and connection flaps 22 are provided between adjacent headers 23 on top of the light pipe heated surface 20.

The evaporators at all levels are suspended on a large plate beam of a boiler steel frame 12 through hanging devices 11.

The heated face module inner membrane wall 19 is reinforced with rigid beams 13.

The steam pocket 8 is arranged on the steel frame large plate beam.

The water volume of the steam drum 8 is not less than 1.2 times of the maximum evaporation capacity of the boiler.

The electric furnace waste heat boiler adopts single-pressure natural circulation, full-suspension structure and horizontal arrangement. The heated surface modules in the boiler are all suspended on a large plate beam of a boiler steel frame through a hanging device 11, a steam drum 8 is placed at the top of the large plate beam, and the whole heated surface expands downwards. The smelting waste gas of the electric furnace enters each heating surface module of the waste heat boiler from the horizontal direction, passes through the inlet cooling smoke hood 1, the evaporator I2, the evaporator II3, the evaporator III4, the evaporator IV5 and the economizer 6 in sequence, and is finally discharged through the outlet flue 7, and the temperature of the waste gas can be rapidly reduced to about 250 ℃ from about 850 ℃. A natural circulation loop is formed between the heating surface module and the steam pocket 8 through an ascending pipe 9 and a descending pipe 10 to generate steam, and meanwhile, most of ash is settled and enters a water-cooled ash bucket 17 through the actions of a shock wave ash blower 15, inertial separation, gravity falling and the like, and enters an ash conveying system 14 after being cooled through the water-cooled ash bucket 17. The heating surfaces are all in a modular design, and the convection heating surface, the radiation heating surface and the water-cooling ash bucket are integrated on one heating surface module, so that the transportation and the installation are convenient. After the assembly of all the heating surface modules is finished, a complete flue gas channel is formed, the periphery of the complete flue gas channel is provided with a membrane wall 19, the middle of the complete flue gas channel is provided with a light pipe heating surface 20 with a light pipe group, the lower part of the high-temperature section is provided with a water-cooled ash bucket 17, the lower part of the low-temperature section is provided with a steel ash bucket 16, and the ash bucket is connected with an ash conveying system 14, so that a complete closed loop system for cooling flue gas and. The radiation stop block 21 is arranged at the position of the header 23 with large heat load, so that the heat load intensity of the connecting folded plate 22 is reduced, and the reliability of the connecting position under the alternating working condition is protected.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. An electric furnace exhaust-heat boiler is characterized in that: the electric furnace waste heat boiler is horizontal and comprises an inlet cooling smoke hood, an evaporator, a coal economizer, an outlet flue and an ash conveying system; the evaporators are arranged in multiple stages, and the evaporators are integrally suspended; the inlet end of the evaporator is provided with an inlet cooling smoke hood, and the outlet end of the evaporator is sequentially provided with a coal economizer and an outlet flue; the top of the evaporator is provided with a steam drum, and the lower part of the evaporator is provided with an ash conveying system.

2. The electric furnace waste heat boiler as claimed in claim 1, characterized in that: the evaporator comprises an evaporator I, an evaporator II, an evaporator III and an evaporator IV.

3. The electric furnace waste heat boiler as claimed in claim 2, characterized in that: shock wave soot blowers are arranged in each stage of evaporator; the bottoms of the evaporator I, the evaporator II and the evaporator III are respectively provided with a water-cooled ash hopper connected with an ash conveying system; and steel ash hoppers connected with an ash conveying system are arranged at the bottoms of the evaporator IV and the economizer.

4. The electric furnace waste heat boiler as claimed in claim 3, characterized in that: heating surface modules are integrated in the evaporators at all levels; the heating surface module is connected with the steam drum through an ascending pipe and a descending pipe; the heating surface modules in the evaporator I, the evaporator II and the evaporator III comprise membrane walls at the periphery, a light pipe heating surface in the middle and a cold ash pipe at the lower part; the water-cooled ash bucket comprises an ash cooling pipe at the lower part and a part of membrane wall; and the heating surface module in the evaporator IV comprises peripheral membrane walls and a light pipe heating surface in the middle.

5. The electric furnace waste heat boiler as claimed in claim 4, characterized in that: and a radiation stop block is arranged between adjacent header tanks at the top of the heating surface of the light pipe.

6. The electric furnace waste heat boiler as claimed in claim 4, characterized in that: and each evaporator is suspended on the boiler steel frame large plate beam through a hanging device.

7. The electric furnace waste heat boiler as claimed in claim 4, characterized in that: the membrane wall is reinforced with rigid beams.

8. The electric furnace waste heat boiler as claimed in claim 1 or 6, characterized in that: the steam pocket is arranged on the steel frame large plate beam.

9. The electric furnace waste heat boiler as claimed in claim 7, characterized in that: the water volume of the steam drum is not less than 1.2 times of the maximum evaporation capacity of the boiler.