SU1206309A1 - Method of regulating steam content of cooling medium in transpiration cooling units of metallurgical sets and device for effecting same - Google Patents

Abstract

1. A method for controlling the vapor content of the cooling medium in the evaporative cooling installations of metallurgical units, including the supply to the cooling medium in the heat-loaded parts of the circulation loop, additional, underheated, cooling medium, characterized in that, in order to improve the durability, chiller, part of the coolant circulation flow is supplied from the common standpipe to the cooled parts and maintain equal coolant enthalpies in them, and The proportion of the circulating flow rate is determined by comparing the steam content values in the respective parts of the circulation circuits. 2 .. Steam-steam control device. Hold the cooling medium in the evaporation cooling installations of metallurgical units, containing standpipes and lifting pipes, a Raban separator, cooled parts, intermediate standpipes and distributing manifolds with control valves, characterized by that, in order to increase the durability of the cooling parts by improving the circulation of the cooler, intermediate discharge collectors are placed along the height of the furnace one from another at distances corresponding to equal hydraulic These are the resistances of the sections of the contours of the cooled parts located between two intermediate dispensing headers, the cooled parts being provided with instruments for measuring steam content, installed in front of each intermediate dispensing collector and at the outlet of the last cooled part of the circulation circuits. u o od 00 o so

Description

The invention relates to ferrous and nonferrous metallurgy and can be used in blast furnace production.

The purpose of the invention is to increase the durability of the cooled parts by improving the circulation of the coolant.

The drawing shows a blast furnace with an evaporative cooling system with a vertical axial section.

The evaporative cooling system contains cooled parts in the form of refrigerating plates 1, in particular, with two poured coil pipes 2 and 3, combined into a circulating circuit with the help of connecting pipes (rolls) A-6, pilot 7 and 8, and lifting 9 and 10 pipes, distributing 11 and 12 and collecting 13 and 14 collectors and drum-separator 15.

Intermediate ISIS distribution manifolds are located between distributors 11 and 12 and collectors 13 and 14 in the intensive heating zone at distances between each other corresponding to equal hydraulic resistances (shown for one cooling circuit), which are connected to the corresponding common downhole pipe 7 by means of intermediate standpipes T9-21, on which control valves are installed 22-24 Similar intermediate collectors are connected to a common standpipe 8. Intermediate headers can also be connected schats water conduit with service water.

On the connecting pipes 4-6 and at the outlet from the last cooling plate 1, devices 25 are installed for measuring steam content.

With relatively small heat fluxes, the device for controlling steam content in the evaporative cooling scheme works as follows.

Circulating water from the drum-separator 15 enters the common standpipe pipes 7 and 8, of which, through the distribution manifolds 11 and 12, is led into the coil pipes 2 and 3 of the cooled parts-cooling plates 1 interconnected along the height of the furnace with connecting pipes 4- 6 Formed in the cooled parts of the steam pipe to the mixture through the lifting pipes 9 and 10 is discharged into the drum separator 15.

With an increase in heat fluxes, which is characterized by an increase in mass vapor content in the cooling of the mixture, and, accordingly, an increase in the steam output, which is controlled by furnaces 25, the height of the circulating water from the common standpipe 7 enters the most thermally loaded cooling plates 1 through intermediate standpipes 19-21, distributing collectors 16, 17 or 18. At maximum heat flux, all intermediate distributing collectors 16-18 work.

The number of intermediate distributing collectors and the distance between them in height is chosen specifically for each evaporative cooling installation and depends on its technological and design features.

Since the enthalpy of the circulating water, the flow from the distributing collectors 16–18 to the plates 1 is much lower than the enthalpy of the medium in de -. tal x, then the total value of enthalpy in chilled coaxial pipes of Euvic pipes 2 and 3 decreases, which leads to a decrease in their vaporization. At the same time, the flow rate of the circulating water through the cooled parts located below the intermediate collector, for example, collector 16, is somewhat reduced, which leads to an increase in steam content. The amount of circulating water supplied through the intermediate distribution manifolds and the number of operating intermediate distribution manifolds is determined by the steam output, the relative change in steam content in each part of the lifting circuit between the intermediate distribution manifolds and the total circulating flow rate in the installation.

As a result of a comparative analysis with the use of a computer and in accordance with the required amount of additional circulating water, a signal is supplied to the control valves 22-24.

Thus, additional circulating water is supplied as much as is necessary to provide approximately equal enthalpy values for each of the zones located along the height of the furnace between the intermediate distribution manifolds.

At the same time, the optimum cooling mode is maintained in all ranges of variation of the VIO operating parameters (pressures and heat fluxes

Example. The domain oven works with evaporative cooling in the areas of shoulders and charge. In connection with the intensification of the blast-furnace process, the heat fluxes to the cooling plates increase, which leads, due to an increase in the hydraulic resistance, to a decrease in the circulation flow rate and, accordingly, to an increase in the steam content in the code from the cooling tubes of the mine coolers to 0.15 (at a rate of not exceeding 0.10) and ST to reduce the circulation rate in these tubes to 0.3 m / s (the minimum acceptable value of this speed is 0.4 m / s). At the same time, in the lower zones (the shoulders are the 3rd row of the mine) the circulating water does not boil (the steam content is zero) and its velocity is 0.65 m / s. Such a situation can cause a failure of the cooling tubes of the cooling plates, a deterioration in the quality of their cooling and, as a result, an increase in the body temperature of the cooling plate.

To increase the resistance of the cold plates, part of the circulating water (180 tons / h) from the common standpipe (the flow rate is 342 tons / h) is fed into the cooling plates, starting from the fourth zone of the mine (the most heat loaded). In the zones of the shoulders — the third row of the mine, the flow rate is 162 t / h, and starting from the fourth row of the shaft through the cooling plates. The entire circulating flow rate of the installation, i.e. 342 t / h Due to this distribution of circulating

The flow rates are approximately equal to the values of the enthalpy of the circulating water at the outlet from the upper one, starting with the 4th row, the shaft, and in the lower (shoulders — the 3rd row of the shaft) furnace zone.

Such distribution of circulating water is obtained by means of intermediate lowering and distributing collectors located between the third and fourth rows of the mine, while the sections of the contours located before the intermediate distributing collector And after it have approximately equal hydraulic resistances.

The difference in the enthalpy values of the medium at maximum

The heat fluxes of the upper and lower zones, separated by an intermediate distribution manifold, are shown in the table.

Pressure in the drum separator, ata

The ratio of the enthalpies of the upper and lower zones,%

The optimal value of the controlled value of the vapor content of the upper and lower zones

15

20

25

The PED of the cooling medium at the outlet of the lower zone is 0.05, of the upper 0.07, and the circulation rate in the zones is approximately the same and is 0.53 m / s.

The advantages of the proposed method and device are as follows. The method and the device allow evenly and in accordance with the heat fluxes to distribute the circulating water supply in such a way that a smaller amount goes to a zone of less heating, and a larger amount goes to a zone of high heat fluxes.

amount of circulating water. This also changes the enthalpy of the cooling water. This makes it possible to increase the height of the steam-containing section due to boiling of circulating water in the zone with lower heat fluxes, and to reduce the values of steam content in zones with higher heat fluxes. The latter circumstance leads to a decrease in the hydraulic resistance of the circuit. On this basis, the total useful circulation pressure in the circuit increases, the heat transfer coefficients increase, the hydraulic characteristics of the PIOs improve, and consequently the heat transfer conditions, thereby increasing the resistance of the parts.

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Compiled by R.Seifulov Editor N. Yatsola Tehred 3.Paly

Order 8652/26 Circulation 552Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, Proektna St., 4

Corrector C.1Pecnar

Claims (2)

1. A method of regulating the vapor content of the cooling medium in evaporative cooling installations of metallurgical units, including supplying to the cooling medium in the heat-loaded parts of the circulation circuit an additional “yugel, pre-saturated, coolant medium, characterized in that, in order to increase the durability of the cooled parts by improving circulation cooler, part of the circulating flow rate of the cooler is fed from the common downpipe to the parts to be cooled and maintain equal enthalpies of the cooler in them, and the other parts of the circulation flow rate are determined by comparing the vapor content values in the corresponding parts of the circulation circuits. 2. Paroso control device. holding the cooling medium in the evaporative cooling installations of metallurgical units, containing lowering and lifting pipes, a drum separator, cooled parts, · intermediate lowering pipes and distributing manifolds with control valves, characterized in that, in order to increase the durability of the cooling parts by improving solutions of the cooler circulation, intermediate distributing collectors are located one above the other at the height of the furnace at distances corresponding to equal hydraulic resistances of the sections of the cooling circuits waiting parts located between two intermediate distributing manifolds, and the cooled parts are equipped with devices for measuring the steam content installed in front of each intermediate distributing collector and at the outlet of the last cooled part of the circulation circuits.