RU2560464C2 - System of evaporation cooling of metallurgical unit - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: system of evaporation cooling comprises cooled elements and a separator drum with connecting communications and pipeline fittings. Besides, the system is equipped with a facility of mechanical compression of steam made in the form of at least two steam compressors serially connected with the help of connecting pipelines and connected by a saturated steam pipeline to the separator drum.

EFFECT: increased efficiency of operation of the system of evaporation cooling.

3 cl, 1 dwg

Description

The inventive object relates to ferrous metallurgy and can be used for evaporative cooling of blast furnaces and hot blast valves of air heaters of blast furnaces.

Closest to the set of features to the claimed object is a prototype system of evaporative cooling of a metallurgical unit, containing cooled elements and a drum separator with connecting communications and pipe fittings. Moreover, the prototype is equipped with a system for using the heat of the generated steam to heat the combustion air supplied to the burners of the blast furnace air heater connected to the drum-separator (Aut. St. No. 1321452, IPC C21B 7/10, publ. 07.07.87).

The claimed object and the selected prototype coincide with such essential features. Both systems contain cooled elements and a drum-separator with connecting communications and pipe fittings.

Analysis of the technical properties of the prototype, due to its features, shows that the receipt of the expected technical result when using the prototype is impeded by such reasons. A low-grade water vapor is generated in the prototype system, which is not suitable for use in technological and energy purposes (steam is produced with an absolute pressure of not more than 1.5 bar and a temperature of not more than 111 ° C), such steam is characterized by a high content of water condensate and its impossibility transportation over long distances. This leads to the fact that this steam is used for heating or simply discharged into the atmosphere, while about 40 t / h of prepared chemically purified deaerated water is irretrievably lost. In addition, the steam released worsens the environmental situation, and in winter, condensate in the form of ice settles on the metal structures of production facilities, disrupts the operation of the equipment, and leads to the risk of injury to staff. All this leads to a decrease in the efficiency of the evaporative cooling system of the metallurgical unit as a whole.

The claimed object is based on the task of creating such a system of evaporative cooling of a metallurgical unit, in which improvements by introducing new elements and new connections between elements will make it possible to achieve a technical result when using the inventive object, which consists in increasing the efficiency of the evaporative cooling system of a metallurgical unit.

The task is solved due to the fact that the evaporative cooling system of a metallurgical unit, containing cooled elements and a drum separator with connecting communications and pipe fittings, in accordance with the claimed technical solution, is additionally equipped with a means of mechanical compression of steam, connected by steam conduit of saturated steam to the drum - a separator and made in the form of at least two series-connected vapor compressors.

In some cases, the execution of the claimed system may be characterized in that:

- it is additionally equipped with a tool that provides forced circulation of the cooling medium;

- steam compressors are made rotary with an axial inlet part and a radial nozzle, which is made expanding, equipped with an electric drive and a system for supplying and injecting chemically cleaned deaerated water and condensate drainage.

When using the inventive facility, it is possible to achieve a technical result consisting in increasing the efficiency of the evaporative cooling system of a metallurgical unit while increasing the parameters of steam generated by it and while ensuring the possibility of its transportation and further use for technological and energy needs. In addition, when using the inventive object, an additional technical result is achieved, consisting in reducing losses of chemically purified deaerated water.

Between the set of essential features of the claimed object and the achieved technical result there is such a causal relationship.

The additional equipment of the inventive system of evaporative cooling by means of mechanical compression of steam, which is connected by a steam line of saturated steam to the drum-separator and made in the form of at least two series-connected vapor compressors, provides sequential, at least two stages, direct compression of the steam with increasing pressure and with increasing temperature, providing an increase in the parameters of the steam generated by the evaporative cooling system of the metallurgical unit, as well as echivaya possibility of its transport and use for process and energy needs. In addition, increasing the parameters of steam to such values that allow it to be used for technological and energy needs, prevents the loss of chemically purified deaerated water and reduces its consumption for the preparation of steam for technological and energy processes, into which superheated steam is sent from the inventive system.

Additional equipment of the inventive system with a means for forcing the circulation of the cooling medium (for example, circulation pumps), allows for optimal cooling medium speeds in the cooling circuits, reduces the likelihood of pulsating oscillations of the cooling cooling circuits, improves the parameters of the steam-water mixture formed in the cooled elements, and helps to increase the efficiency of the subsequent processes of increasing the parameters of steam in vapor compressors, which, in turn, series, provides stability, reliability and increased efficiency of the evaporative cooling system of the metallurgical unit as a whole.

The equipment of the inventive system with at least two series-connected vapor compressors, which are made rotary with an axial inlet part and a radial nozzle made expanding, and equipped with an electric drive, as well as a system for supplying and injecting chemically cleaned deaerated water and for condensate drainage, can technologically simply provide a stepwise increase in pressure and temperature steam without exceeding critical values at the lowest cost, and also allows you to ensure reliability, efficient nce and durability of parokomperessorov. All this provides an increase in the efficiency of the evaporative cooling system of the metallurgical unit while increasing the parameters of the steam it produces, and also provides the possibility of its transportation and further use for technological and energy needs.

The use of rotary-type vapor compressors with an axial inlet part and a radially expanding nozzle makes it possible to constructively simply ensure the greatest efficiency of the step-by-step (step-by-step) increase of steam parameters, to optimize the steam speed and pressure at the outlet of the previous vapor compressor and to the inlet of the next one when the vapor compressors are connected in series, to ensure steam transportation for further use for technological and energy needs in relation to quality and quantity nym indicators vapor generated by evaporative cooling system of a metallurgical unit and used in the metallurgical industry. In addition, it provides compact placement of at least two series-connected vapor compressors in the conditions of existing plants with minimal cost.

Equipping rotary steam compressors with a system for supplying and injecting chemically purified deaerated water and condensate drain allows water to be supplied and injected into the steam compressor, for example by spraying with nozzles, as well as to prevent the accumulation of droplet moisture in the form of condensate and to ensure the optimal operation of the steam compressor. In addition, water injection provides cleaning of the working body of the steam compressor during operation and the prevention of sticking, which, in turn, prevents its imbalance. All this provides an increase in the efficiency of the evaporative cooling system of the metallurgical unit as a whole with an increase in the parameters of the steam it produces and with the possibility of its transportation and further use for technological and energy needs.

The essence of the claimed object is illustrated by the drawing, which shows a schematic diagram of the evaporative cooling system of such a metallurgical unit as a blast furnace, with the image of four vapor compressors.

In the drawing, the positions denote such elements:

1 - drum separator;

2 - refrigerating plates;

3 - lowering pipeline;

4 - main distribution manifold;

5 - suction section of the main distribution manifold;

6 - pressure section of the main distribution manifold;

7 - suction pipe;

8 - circulation pumps;

9 - discharge pipeline;

10 - lowering pipelines;

11 - lowering collectors;

12 - individual lowering pipelines;

13 - connecting kalach;

14 - individual lifting pipelines;

15 - lifting manifolds;

16 - lifting pipelines;

17 - steam pipe saturated steam;

18 - steam compressors;

19 - connecting steam lines;

20 - steam pipe superheated steam for technological needs;

21 - pipeline for supplying chemically purified deaerated water;

22 - booster pump of chemically purified deaerated water;

23 - discharge pipelines of chemically purified deaerated water;

24 - condensate pipelines for drainage of condensate;

25 - condensate collector;

26 - a common condensate drain pipe;

27 - steam trap;

28 - condensate pump;

29 - pipe fittings (check valve);

30 - pipe fittings (shutter);

31 - pipe fittings (shutter);

32 - pipe fittings (shutter).

In a specific embodiment, the inventive evaporative cooling system, for example, a blast furnace, is equipped with two separate vertical cooling sections of a similar design, which together cover the blast furnace in height from two opposite sides (one section is shown in the drawing). Each vertical section contains a drum-separator 1 and refrigeration plates 2 with connecting communications and pipe fittings.

The drum-separator 1 is connected by a common lowering pipe 3 to the main distribution manifold 4, which is divided by a pipe fitting 29 (check valve) into a suction section 5 and a pressure section 6. In this case, the suction section 6 is connected to a common lowering pipe 3, as well as through pipe fittings 30 (shutter) is connected to the suction pipe 7 of the circulation pumps 8 (one working, one standby), and the pressure section 6 is connected through pipe fittings 31 (shutter) to the discharge pipe 9 of the circulation pumps 8 and through pipe fittings 32 (shutter), downcomers 10, downcomers 11 and individual downcomers 12 - with the bottom row of refrigeration plates 2 shoulders of the blast furnace. The cooling plates 2 are made, for example, with cooling tubes in the form of coils filled in two planes (not shown in the drawing), while the cooling plates 2 (their coils) are connected in height by cams 13, forming a vertical circulation circuit. Each section contains, for example, four vertical circulation cooling circuits. The upper row of refrigerating plates 2 (their coils) of the blast furnace shaft is connected through individual lifting pipelines 14, lifting manifolds 15, lifting pipelines 16 to the drum-separator 1. The drum-separator 1 is located at the highest point of the described circulation loop.

In addition, the drum separator 1 is connected via a saturated steam steam line 17 to, for example, four rotary steam compressors 18, which are made with an axial inlet part and a radial expanding nozzle and connected in series using connecting steam pipes 19. The last (along the steam) vapor compressor 18 connected to the steam line of superheated steam 20 for the removal of steam for technological needs.

Rotary steam compressors 18 are equipped with electric drives that provide rotation of the working body (not shown in the drawing) and a system for supplying and injecting chemically cleaned deaerated water and condensate drain, which contains a water supply pipe 21, a boost pump 22, pressure pipelines 23 for supplying water to the steam compressors 18, and also the condensate pipelines 24 for drainage of condensate through the steam traps 27 to the condensate collector 25, which is connected by a common condensate drain pipe 26 to the pipe 21. Condensate injection into the pipe 21 is provided using a condensate pump 28.

Cooling the blast furnace after the initial filling of the inventive system is as follows. From the drum-separator 1, cooling water enters through a common drain pipe 3 to the suction section 5 of the main distribution manifold 4, from where, with the pipe fittings 30 (valve) open, it is sucked through the suction pipe 7 by circulation pumps 8, which provide the necessary pressure to overcome the hydraulic resistance of the system and creating the optimal speed of the steam-water mixture in the coils of the refrigeration plates 2. Next, the water enters through the discharge pipe 9 through an open pipe th valve 31 (valve) to the pressure section 6 of the main distribution manifold 4, creating the necessary pressure to close the pipe fittings 29 (check valve) and ensuring that the pressure section 6 is disconnected from the suction section 5. Then, the cooling water flow is divided, for example, into four parallel flows according to the number of vertical cooling circuits (in this case, a predetermined water flow rate is ensured in each cooled circuit) and with open pipe fittings 32 (closures), the downpipes 10 go to the downpipes headers 11, from which on individual lines 12 in a downward water flows to the lower number of cooling plates 2 shoulders blast furnace. The water passing through the coils takes heat from the refrigeration plates 2 and heats up to form a steam-water mixture. The use of circulation pumps 8 helps to increase the efficiency of formation of a steam-water mixture and increase its parameters. The resulting steam-water mixture from the upper row of refrigerating plates 2 of the blast furnace shaft through individual lifting pipes 14 enters the lifting manifolds 15 and then through the lifting pipes 16 to the drum separator 1, where saturated steam is separated from the water. Water from the drum-separator 1 through a common drain pipe 3 again enters the suction section 5 of the main distribution manifold 4, and the process is repeated.

The separated saturated steam with an absolute pressure of 1.5 bar and a temperature of ~ 111 ° C from the drum separator 1 is fed through a saturated steam line 17 to the axial inlet part of the first rotary vapor compressor 18 (first compression stage), where its pressure rises to 2 bar, and temperature up to 121.15 ° C. Next, the steam from the radial expanding nozzle of the first vapor compressor 18 through the connecting steam line 19 enters the axial inlet part of the second vapor compressor 18 (second compression stage), where its pressure and temperature increase, respectively, to 2.7 bar and 130.15 ° C. Then the steam from the radial expanding nozzle of the second vapor compressor 18 through the connecting steam line 19 enters the axial inlet part of the third vapor compressor 18 (third compression stage), where its pressure and temperature increase, respectively, to 3.6 bar and 139.65 ° C. Then the steam from the radial expanding nozzle of the third vapor compressor 18 through the connecting steam line 19 enters the axial inlet part of the fourth vapor compressor 18 (fourth compression stage), where its pressure and temperature increase, respectively, to 4.6 bar and 200 ° C. Then the superheated steam from the radial expanding nozzle of the fourth vapor compressor 18 is sent to the technological needs through the steam conduit 20 of the superheated steam.

The use of four series-connected rotary vapor compressors allows you to increase the parameters of steam with an initial absolute pressure of 1.5 bar and a temperature of 111.4 ° C to a final absolute pressure of 4.6 bar and a temperature of 200 ° C at a flow rate of 12.9 t / h, making it possible transportation and further use in the blast furnace shop, for example, for blast furnace tops, hoppers of a coneless loading device, for purging equalizing valves and probes, for purging gas pipelines of clean gas for air heaters, for purging natural gas pipelines, when filling the dust collector, to seal the shut-off valve seat, to heat the shut-off valve stem seal, in a screw conveyor, to moisten the blast and heat the nitrogen pipes and pulse paths.

To ensure the optimal operation of the vapor compressors 18, as well as to clean their working body and to prevent sticking from the pipeline 21, by means of a boosting pump 22 through the injection pipes 23 they are supplied with chemically purified deaerated water, which is injected into the housing of the vapor compressors, for example, by spraying using nozzles ( not shown in the drawing). In this case, droplet moisture in the form of condensate is discharged with the help of steam traps 27 through the condensate pipelines 24 to the condensate collector 25, from which, when the condensate pump 28 is operating through the pipeline 26, it is injected into the pipe 21.

In the inventive cooling system of a metallurgical unit, water losses are replenished with chemically purified deaerated water, which is supplied to the drum-separator 1, ensuring constant maintenance of its required level (not shown in the drawing).

In the case of operation of the inventive system without using means providing forced circulation of the cooling medium (without circulation pumps 8), with closed pipe fittings (closures) 30 and 31 on the suction 7 and pressure 9 pipelines, respectively, and when there is no water pressure on the pressure section 6, it opens pipeline valves 29 (non-return valve), ensuring the flow of water from the suction section 5 directly into the pressure section 6 of the main distribution manifold 4. Further, the operation of the system without The use of a means providing forced circulation of the cooling medium is similar to the operation of the system with its use, and the circulation of water is provided due to the difference in the specific gravities of water and the steam-water mixture.

All this by increasing the parameters of the steam generated by the inventive system, and by ensuring the possibility of its transportation and further use for technological needs, provides increased efficiency of the evaporative cooling system of the metallurgical unit as a whole.

Claims (3)

1. The evaporative cooling system of a metallurgical unit, containing cooled elements and a drum separator with connecting communications and pipe fittings, characterized in that it is equipped with at least two vapor compressors connected in series via connecting steam pipelines, the first of which is connected with a saturated steam steam pipeline to the drum -separator, and the last - with a steam line of superheated steam. 2. The system according to claim 1, characterized in that it is additionally equipped with a means for forcing the circulation of the cooling medium. 3. The system according to claim 1 or 2, characterized in that the steam compressors are made rotary with an axial inlet part and a radial nozzle, which is made expandable, equipped with an electric drive and a system for supplying and injecting chemically cleaned deaerated water and condensate drainage.

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