SU1257096A1 - Assembly of high-temperature stoves - Google Patents

Description

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The invention relates to ferrous metallurgy, in particular to the structures of a blast furnace unit, and can be used in all areas of the household where high-temperature heating of gases is required.

The aim of the invention is to increase the heating efficiency of the blow when the heaters are heated with low-calorie gas, increasing the accuracy of maintaining the flow rate, pressure and temperature of the combustion air.

The drawing shows the block diagram: high-temperature heaters.

The unit of high-temperature air heaters consists of four (three) air heaters 1, the cold air duct 3 is connected to the bottom of the nozzle chamber 2, and the hot air duct 5 is connected to the upper part of the combustion chamber 4. The shut-off gates 6 and 7 are installed at the cold-blowing and exhaust hot-air discharge fittings. A Snort 8-type valve and a diaphragm 9 are installed in front of the cold-air duct 3,

At the end of the air duct 5, a hot blowing is made narrowing 10, which is connected to cold air blowing duct 3 by means of connecting duct 11, as well as through a mixed duct blowing pipe 12 to an injector of an injector mixer 13, connected to a mixing pipe 14c with a heated collector 15 of air. The latter is connected by one side to the air ducts 16 to the inlet burners, and the other to the suction nozzle of the mixer 17,

The air piping system is equipped with shut-off devices: gate 18 on the connecting pipe 11 of the cold blowing section, 19 on the supply lines to the burners 16, section 20 on the suction nozzle of the mixer 17, section 21 at the end of the section 5 that blows, and a regulating throttle 22 on the connecting pipe cold duct air duct, choke 23 on duct ducts supplying to the burners, choke 24 on a mixed duct blowing, choke 25 on the suction nozzle of the mixer.

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Inside the air duct 5 there is a hot blowing, before the annular air duct 26, the narrowing is made in the form of a Venturi tube 27, and on the connecting 11 air duct of the cold

The measuring diaphragm 28 is installed. The pipeline sections of the mixed blowing pipe 12 and the heated air collector 15 are equipped with thermocouples 29 and 30.

The unit of high-temperature air heaters operates as follows. at once.

In the sequential operation mode of the air heaters, one of them (for example, the 1st one) is on the blast, and the rest are on the heating. At the same time, the gates 6 and 7 on the 2.3, D-ohm air heaters are closed, and on the 1st heater, they are open, the gates 18, 19, 2.0 and the throttle 24 are closed. The cold blast enters the air heater 3 through the cold blower 1 (the valve of the Snort 8 type is closed), where it heats up and enters the air duct 5 hotly. Here the blast can be divided into two streams: one (main) enters through the annular air duct 26 into the blast furnace, and the other through the duct system to the burners of the heaters. To start a part of a hot blow on the air heaters, it is necessary to open the gates 18, 20, 21 and

35 19. At the same time, a part of the cold blowing through the connecting air duct 11 and the hot air duct blowing through the restriction 10 enters the duct 12 mixed blowing, where the temperature of its mixture does not exceed 700-. Then the blast enters the nozzle of the mixer-injector 13 and, having flowed out of it, creates a vacuum in the mixing duct 14. Due to

 The vacuum through the suction inlet of the mixer 17 is sucked in atmospheric air, which, mixing with the blast, enters the collector 15 and the wires 50 supplied to the burners of the air 50.

By using heated air up to 400-600 ° C, a temperature of 1400-1450 ° C is provided under the dome of the air heaters when they are heated only with blast-furnace gas. The amount of injected atmospheric air is regulated by the throttle 25, which is affected by the regulator

thirty

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air temperature entering the burner. This temperature is measured by a thermocouple 30. The air flow per burner is controlled by a-throttle 23. The reliable operation of throttle 24 is ensured by a relatively low blowing temperature (700-800 ° C), which is measured by thermocouple 29 and adjusted by a potentiometer with a positioning device using throttle 22 .

The total flow rate of the cold blast to the blast furnace complex is measured using a measuring diaphragm 28 and the flow rate to blow to the furnace is measured using a Venturi pipe 27.

The change in the flow rate of the blow to the furnace can be carried out with the aid of droplets 22 and 24.

The implementation in the air duct of hot blowing of a narrowing with a diameter of 0.3-0.5 of the diameter of the air duct is due to the following.

The consumption of hot blow for heating air heaters is 8-15% of the total consumption and depends

Editor N.Shvydka Order 4881/20

Compiled by R.Seifulov

Tehred M. Khodiich Proofreader M. Maksimishinets

Circulation 552Subscribe

VNIIPI USSR State Committee

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

Production and printing company, Uzhgorod, st. Project, 4

964

from the heat of combustion of the blast furnace gas, thermal power of air heaters and the temperature under the dome.

When selecting a part, blowing from the end of the air duct with a hot blow stabilizes the laying temperature along the length, since in the known design of the heater unit the temperature of the laying along the length of the air flow varies with time and depends on which apparatus is on the blast.

When the diameter of the constriction is reduced

less than 0.3 diameter of the air duct

the flow rate is too low to blow, which does not provide the desired air heating temperature.

When the contraction diaimeter is increased to more than 0.5 of the diameter of the air duct, the flow rate of hot blowing is excessive, which increases the flow rate of the cold blow. The latter is not economically feasible or impossible to limit the performance of the blower.

Claims (1)

1. BLOCK OF HIGH-TEMPERATURE AIR HEATERS, containing hot and cold blast ducts with control and shut-off valves, an injector mixer with a suction nozzle connected by a pipeline to combustion chambers, which is characterized by the fact that, in order to increase the efficiency of heating of blast when heating air heaters, the heaters are low increase the accuracy of maintaining the flow rate, pressure and temperature of the combustion air, the diameter narrowing was performed behind the last air heater in the hot blast duct m 0.3 - 0.5 of the diameter of the hot blast air duct, while the hot blast air duct before narrowing is connected by a pipeline to the cold blast air duct and a mixer injector. . 2. Block pop. 1, the difference is that the hot blast duct in front of the blast furnace ring duct is equipped with a clamp in the form of a venturi, and a measuring diaphragm is installed on the connecting pipe. SU „„ 1257096 12.57096