High and low speed switching control system of dust removal fan

Abstract

The utility model provides a high and low speed switching control system for a dust removal fan, which comprises a converter, a rotating shaft of the converter is provided with an encoder, and the encoder can record the angular displacement of the rotating shaft; the dust removal fan is arranged at the tail end of the converter flue; and the converter master control room receives the angle signal about the converter from the encoder and sends a speed adjusting signal to the dust removal fan. And the encoder is connected with a rotating shaft of the converter through an isolation section. According to the high-speed and low-speed switching control system of the dust removal fan, the high-speed and low-speed switching time is judged according to the angle of the converter, the rotating speed of the fan is adjusted in time, the encoder is protected by arranging the isolation section so as to be away from the influence of high temperature, and safe, effective, accurate and timely high-speed and low-speed switching is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of converter smelting, in particular to a high-speed and low-speed switching control system for a dust removal fan. Background Art

[0002] Converter refers to a metallurgical furnace with a rotatable furnace body used for blowing steel or blowing matte. The converter body is made of steel plates, cylindrical, and lined with refractory materials. It is heated by chemical reaction heat during blowing and does not require external heat sources. It is the most important steelmaking equipment and can also be used for copper and nickel smelting. Converter steelmaking is mainly a steelmaking method using liquid pig iron as raw material. Its main characteristics are: relying on the physical heat of liquid pig iron in the converter and the heat generated by the chemical reaction of various components in the pig iron (such as carbon, manganese, silicon, phosphorus, etc.) with the oxygen fed into the furnace, the metal reaches the composition and temperature required for steelmaking. The furnace charge is mainly molten iron and slag material (such as lime, quartz, fluorite, etc.). To adjust the temperature, scrap steel and a small amount of cold pig iron blocks and ore can be added. In the converter steelmaking process, the carbon in the molten iron reacts with the blown-in oxygen at high temperature to generate a mixed gas of carbon monoxide and a small amount of carbon dioxide, namely converter gas. The amount of converter gas generated in a smelting process is not balanced, and the composition also changes. Usually, the gas recovered from multiple converter smelting processes is cooled and dust-removed, input into the gas storage cabinet, mixed and then delivered to users.

[0003] During the converter production process, the flue gas produced by blowing is cooled by the active smoke hood and vaporization cooling flue, then enters the spray tower for cooling and rough dust removal (large particle size dust), and then passes through the upward long-neck adjustable throat annular seam venturi for fine dust removal (small particle size dust), and finally passes through the multifunctional cyclone for cooling, dehumidification and dehydration treatment;

[0004] At present, the fans for primary dust removal of converters in the industry generally adopt high-speed and low-speed switching operation modes. Generally speaking, high-speed operation is adopted during converter blowing, and low-speed operation is adopted when adding scrap steel and adding iron in front of the converter, tapping steel at the back of the converter, splashing slag to protect the furnace, and pouring slag in front of the converter. However, the corresponding time points of high-speed and low-speed start and end are mainly based on experience judgment and are not very clear. For example, low-speed operation is adopted during the period when high-speed operation should be adopted, resulting in poor smoke exhaust, and high-speed operation is adopted during the period when low-speed operation should be adopted, resulting in waste of electric energy.

[0005] The utility model attempts to provide a high- and low-speed switching control system for a dust removal fan, and attempts to timely and effectively realize the high- and low-speed switching adjustment of the dust removal fan of a converter. Utility Model Content

[0006] The utility model attempts to provide a high- and low-speed switching control system for a dust removal fan, and attempts to timely and effectively realize the high- and low-speed switching adjustment of the dust removal fan of a converter.

[0007] The utility model provides a dust removal fan high-low speed switching control system, comprising: a converter, an encoder is arranged on the rotating shaft of the converter, and the encoder can record the angular displacement of the rotating shaft; a dust removal fan, the dust removal fan is arranged at the end of the converter flue; and a converter main control room, the converter main control room receives a rotation angle signal about the converter from the encoder and sends a speed adjustment signal to the dust removal fan.

[0008] Furthermore, the encoder is connected to the rotating shaft of the converter through an isolation section.

[0009] Furthermore, part or all of the isolation segment is made of thermal insulation material.

[0010] Furthermore, a human intervention module is also provided in the converter main control room.

[0011] According to the dust removal fan high and low speed switching control system provided by the utility model, the high and low speed switching time is determined according to the angle of the converter, so that the fan speed can be adjusted in time, and the encoder is protected by setting an isolation section to keep it away from high temperature influence, so as to realize safe, effective, accurate and timely high and low speed switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Shown is a schematic diagram of a converter in an embodiment of the present utility model.

[0013] Figure 2 Shown is a schematic diagram of a converter in another embodiment of the present invention.

[0014] Reference numerals:

[0015] 1: converter; 2: shaft; 3: encoder; 4: isolation section. DETAILED DESCRIPTION

[0016] In order to provide a further understanding of the purpose, structure, features, and functions of the present invention, the present invention is described in detail below with reference to the embodiments.

[0017] The utility model provides a high-speed and low-speed switching control system for a dust removal fan, including: Figure 1 As shown, a converter 1 is provided with an encoder 3 on the rotating shaft 2 of the converter 1, the encoder 3 can record the angular displacement of the rotating shaft 2, the encoder 3 is used to determine the rotation angle of the converter 1 and send a rotation angle signal of the converter 1 to the converter main control room; a dust removal fan, the dust removal fan is arranged at the end of the converter flue; and a converter main control room, the converter main control room receives the rotation angle signal of the converter 1 from the encoder 3 and sends a speed adjustment signal to the dust removal fan.

[0018] In the converter smelting cycle, the blowing time is about 14 to 15 minutes, during which the dust removal fan needs to be operated at high speed. The operation of the dust removal fan generally includes high-speed operation and low-speed operation. For example, the dust removal fan speed is 1380-1400r / min when running at high speed, and the dust removal fan speed is 600-700r / min when running at low speed. Generally speaking, high-speed operation is adopted during converter blowing, and low-speed operation is adopted when the converter adds scrap steel and iron in front of the furnace, taps steel at the back of the furnace, splashes slag to protect the furnace, and pours slag in front of the furnace. However, the time point of high-speed and low-speed switching of the dust removal fan now depends on the experience of the operator, resulting in unclear time points for high-speed and low-speed switching. For example, low-speed operation is adopted during the period when high-speed operation should be adopted, resulting in poor smoke exhaust, and high-speed operation is adopted during the period when low-speed operation should be adopted, resulting in waste of electric energy.

[0019] There is a technical solution that attempts to determine the timing of high-speed and low-speed switching by sensing the dust content in the flue gas through a smoke sensor, but there is a problem of delayed response.

[0020] In the converter smelting cycle, the rotation angle of the converter corresponds to a specific time point in the cycle. In the embodiment of the utility model, an encoder is set to sense the rotation angle of the converter, and the encoder sends the sensed rotation angle signal to the converter main control room, and the converter main control room selects the appropriate converter rotation angle to switch the dust removal fan to high and low speed. The converter is the source of converter smoke. Determining the timing of high and low speed switching according to the rotation angle of the converter can realize the high and low speed switching of the dust removal fan in a timely and accurate manner.

[0021] Further, such as Figure 2 As shown, the encoder 3 is connected to the rotating shaft 2 of the converter 1 through the isolation section 4. A part or all of the isolation section 4 is made of heat insulating material, thereby reducing the influence of the high temperature of the converter on the encoder 3 and extending the service life of the encoder 3.

[0022] Furthermore, a human intervention module is also provided in the converter main control room. The human intervention module is used to send out human intervention signals. For example, after the converter blowing is completed, the content of carbon, silicon, manganese, sulfur, phosphorus and other elements in the molten steel does not meet the requirements of the steel grade, and the converter needs to be reversed from the back of the furnace to the zero position to blow oxygen again, which is called secondary supplementary blowing. When secondary supplementary blowing is required (the dust removal fan needs to run at high speed at this time), the human intervention module sends out a secondary supplementary blowing signal. At the same time, the secondary supplementary blowing signal has no effect on the original high-low speed switching program. In other words, when secondary supplementary blowing is required, secondary supplementary blowing is carried out, and the dust removal fan runs at high speed during the secondary supplementary blowing. When the secondary supplementary blowing is cancelled, the dust removal fan still runs according to the original high-low speed switching program.

[0023] For example, the original high-speed start and end time period: at the start time, the converter angle is about -70 degrees; at the end time, the converter angle is +67 degrees, and there is a delay of about 2 minutes. In the time periods of adding scrap steel, adding iron, and tapping steel from the furnace, there are 3 minutes and 2 minutes respectively. It could have been run at a low speed, but it is in a high-speed operation period, resulting in a waste of electricity.

[0024] After adjustment by the experimenters, when there is a signal on the charging and shaking furnace operating table and scrap steel or iron is added, or when there is a signal on the charging and shaking furnace operating table and the converter angle is minus 60°, there is feedback, with a lag of 1.5 minutes, the dust removal fan starts to increase the speed from 600-700r / min (low speed) to 1380-1400r / min (high speed), and after the dust removal fan increases to high speed, it maintains the speed until the blowing is completed, until the converter tilts forward to 67°, the high-speed period ends, the dust removal fan starts to decrease the speed from 1380-1400r / min (high speed) to 600-700r / min (low speed), and after decreasing to low speed, it maintains the speed until there is a signal on the charging and shaking furnace operating table and scrap steel or iron is added, the converter angle is at minus 60°, and the low speed ends.

[0025] The new high- and low-speed switching control method reduces the high-speed time of adding scrap steel, adding molten iron, and tapping steel from the furnace. The daily benefit is approximately: (98-44)*10*31 / 2*0.88*((3+2) / 60)*40*0.5≈1372 yuan; it plays a certain role in reducing process costs.

[0026] Where:

[0027] 98: The corresponding motor current value when the speed is 1380-1400r / min; unit: ampere;

[0028] 44: The corresponding motor current value at 600-700r / min; unit: ampere;

[0029] 0.88: Power factor of primary dust removal motor;

[0030] 3+2: 3 means adding scrap steel to iron before the furnace saves 3 minutes; 2 means tapping steel after the furnace saves 2 minutes

[0031] minute;

[0032] 40: Number of converter furnaces produced per day; unit: furnace;

[0033] 0.5: price per kilowatt-hour; unit: yuan / kilowatt-hour

[0034] According to the dust removal fan high and low speed switching control system provided by the utility model, the high and low speed switching time is determined according to the angle of the converter, so that the fan speed can be adjusted in time, and the encoder is protected by setting an isolation section to keep it away from the influence of high temperature, so as to achieve safe, effective, accurate and timely high and low speed switching.

[0035] In the description of the present invention, it is necessary to understand that the terms “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside” and “outside” orientations or positional relationships are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0036] The present invention has been described by the above-mentioned relevant embodiments, however, the above-mentioned embodiments are only examples for implementing the present invention. It must be pointed out that the disclosed embodiments do not limit the scope of the present invention. On the contrary, any changes and modifications made without departing from the spirit and scope of the present invention are within the scope of patent protection of the present invention.

Claims

1. A dust removal fan high and low speed switching control system, characterized in that: include: A converter, wherein an encoder is provided on the rotating shaft of the converter, and the encoder is capable of recording the angular displacement of the rotating shaft; A dust removal fan, wherein the dust removal fan is arranged at the end of the converter flue; as well as The converter main control room receives a rotation angle signal of the converter from an encoder and sends a speed adjustment signal to the dust removal fan.

2. The dust removal fan high and low speed switching control system according to claim 1 is characterized in that: The encoder is connected to the rotating shaft of the converter through an isolation section.

3. The dust removal fan high and low speed switching control system according to claim 2 is characterized in that: A part or the whole of the insulating section is made of thermal insulation material.

4. The dust removal fan high and low speed switching control system according to claim 1 is characterized in that: A human intervention module is also provided in the converter main control room.

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