CN115595396A - Method for controlling converter process and end point temperature - Google Patents

Abstract

The invention discloses a method for controlling the process and the end point temperature of a converter, which comprises the following steps: comparing the temperature difference according to the physical heat and the chemical heat of the molten iron by comparing the upper and lower heats, and displaying the specific numerical value of the temperature difference on a control interface; according to the compared temperature difference, the temperature which should be obtained by the current furnace is calculated through the specific value of the temperature of the previous furnace, and whether the reaction in the smelting process is normal is determined according to the quantized data of the process temperature; judging the reasonable slag alkalinity of the current furnace according to the end point components, dynamically adjusting the slag consumption, if the end point components of the furnace are low, orderly reducing the slag alkalinity, and if the end point components of the furnace are high, otherwise; the temperature change can be seen on the control interface in a reading mode, important basis is provided when the temperature is judged in the smelting process, the judgment is not completely carried out by experience, and the error probability of completely depending on manual judgment is reduced.

Description

Method for controlling converter process and end point temperature

Technical Field

The invention belongs to the technical field of metallurgy, and particularly relates to a method for controlling the process and the end point temperature of a converter.

Background

Temperature control is an important parameter in converter steelmaking, the temperature control mainly comprises process temperature control and end point temperature control, the quality of the end point temperature control directly influences technical indexes such as energy, alloy absorption rate, lining life and finished steel quality in a smelting process, the scientific utilization of molten pool temperature is an important means for regulating and controlling the proceeding direction and limit of metallurgical reaction, if the process temperature is properly reduced, dephosphorization is facilitated, and if the temperature is properly increased, carbon oxidation is facilitated. The influence of the bath temperature on the steelmaking process is mainly manifested in the smelting operation, the composition control, etc.

At present, the domestic intelligent steelmaking technology is not mature, most of the domestic intelligent steelmaking technology depends on manual experience judgment, the judgment error probability of the manual experience judgment for continuous production is high, the hit rate of the manual judgment is about 55% -64%, and no effective means is provided.

Disclosure of Invention

The invention aims to provide a method for controlling the process and the end point temperature of a converter.

The technical scheme adopted by the invention for solving the technical problems is as follows: a method of controlling the process and end point temperature of a converter comprising the steps of:

1) Comparing the temperature difference according to the physical heat and the chemical heat of the molten iron by comparing the upper and lower heats, and then displaying the specific numerical value of the temperature difference on a control interface;

2) According to the compared temperature difference, the temperature which should be obtained by the current furnace is calculated through the specific value of the temperature of the previous furnace, and whether the reaction in the smelting process is normal is determined according to the quantized data of the process temperature;

3) And judging the reasonable slag alkalinity of the current furnace according to the end point components, dynamically adjusting the slag consumption, orderly reducing the slag alkalinity if the end point components of the furnace are low, and otherwise.

The invention has the following beneficial effects: the temperature change can be seen on the control interface in a reading mode, important basis is provided when the temperature is judged in the smelting process, the judgment is not completely carried out by experience, and the error probability of completely depending on manual judgment is reduced.

Detailed Description

The present invention will now be described in further detail.

A method for controlling the process and the end point temperature of a converter comprises the following steps:

1) And comparing the upper and lower heats according to the temperature difference between the physical heat and the chemical heat of the molten iron, and displaying the specific numerical value of the temperature difference on a control interface. The charging amount of the previous furnace is 50 tons of molten iron, 8 tons of scrap steel, si:0.45%, molten iron temperature: 1345 ℃, lime addition: 2100kg, light burned dolomite: 825kg, sinter: 1547kg, end point temperature: 1660 ℃, next furnace charge, 49.5 tons of molten iron, 11 tons of scrap steel, si:0.55%, temperature: 1335 ℃, calculating by a temperature model, and adding 2654kg of lime, 987kg of light-burned dolomite, 2410kg of sinter and 1665 ℃ of end point temperature;

2) The temperature which should be obtained by the current furnace is calculated according to the compared temperature difference and the specific value of the temperature of the previous furnace, whether the reaction in the smelting process is normal can be simply seen according to the quantized data of the process temperature, and the process temperature is assisted to be judged manually;

3) And judging the reasonable slag alkalinity of the current furnace according to the endpoint components, if the current furnace endpoint components are low, orderly reducing the slag alkalinity, and if the current furnace endpoint components are high, then the current furnace endpoint components are not high. If the upper limit of the P component of the smelting steel grade is 0.045%, the assay alkalinity in the furnace is 2.82, and the P component is 0.015% -0.025%, the alkalinity can be properly controlled to be reduced from the original 2.8 to 2.6, and the addition of lime and dolomite in each furnace can be automatically calculated according to the slag sample alkalinity by a model, and if the P component of the furnace is controlled to be 0.034% -0.045%, the alkalinity is increased to 3.0 or higher, and the endpoint component is stabilized.

The embodiment is as follows:

1. and performing data comparison and analysis by using computer configuration software, calculating a specific numerical value, comparing the temperature difference between the two furnaces after the two furnaces are compared, comparing the temperature difference with the temperature of the previous furnace, and obtaining the final theoretical temperature.

The temperature reading is directly displayed on the operation picture, so that the temperature display numerical value can be visually seen, and the quantity of lime added into the slag can be seen.

2. The operation can be guided according to the temperature reading in the operation, the operation of the furnace is guided according to the previous furnace data, the temperature does not rise too fast for controlling the quantity of the cold burden, the effect of uniform temperature rise can be achieved, the operation is guided by obtaining the temperature from the blowing end point according to the following table, and the process temperature trend is controlled according to the table:

iron loss (t/kg)	780-820	820-840	840-860	860-880	880-910	910 or more
							One batch (before 3 min)	1700	1720	1740	1750	1770	1770
Two batches (3-6 min)	1670	1670	1685	1690	1700	1710
							Three batches (after 6 min)	1660	1660	1660	1660	1660	1660

3. Utilization of temperature model during process' dry back

When the drying-back phenomenon occurs in the middle stage of blowing, the balance of iron oxide in the slag is unbalanced, the temperature rises unevenly, the iron oxide generation speed is lower than the digestion speed, the iron oxide digestion speed is high due to high temperature, the drying-back is avoided by using a temperature model, if the drying-back is carried out for about 6min in the operation of the previous furnace, the temperature model shows that the temperature is 1680 ℃ during the drying-back, the temperature is controlled to be 1665 ℃ after the beginning of one minute before the drying-back time, then the end point hit temperature is reduced to 1645 ℃, and the temperature is lost due to the drying-back of the previous furnace, so that the temperature of the next furnace is influenced. If blowing is carried out for 9min and drying return indicates that the overall temperature control is higher, the lime melting time is short, the target temperature is controlled to be 1635 ℃ during the next furnace operation, and the temperature of 1660 ℃ can still be obtained due to the loss end point of the drying return temperature.

4. Application in splashing in converting process

The blowing process splash is composed of three reasons, one is that the temperature rises too slowly, leads to the carbon oxygen reaction rate to be too low, and the iron oxide generating speed is greater than the digestion speed, then utilizes temperature model control terminal temperature to be 1675 ℃, and corresponding process temperature control all improves about 15 ℃, can avoid completely, and second is the blowing mid-term splash, and the splash at this moment all is because the splash that bad accent sediment of slagging arouses, and the mode that utilizes temperature model control to return futilely is controlled and can be effectively avoided. Thirdly, splashing caused by high silicon content in molten iron, because the molten iron has high silicon content, excessive cold materials are added in the early stage in the operation to cause the temperature to rise slowly, meanwhile, more active substances are contained in the molten slag, once the temperature rises, metal splashing is caused, the high iron loss in the temperature model is utilized for control, if the iron loss is 840-860t/kg, the temperature control in the blowing process is controlled according to the iron loss of 880-910t/kg, and the splashing caused by high silicon content can be effectively avoided.

5. Use of converting end-point phosphorus level

The phosphorus at the blowing end point is high, if the blowing process has drying back, the control is carried out according to a drying back treatment method, if the blowing process has no drying back, the normal end point P of the final slag is high, which indicates that the whole blowing process is caused by higher control temperature, and the control is carried out by reducing the temperature of the whole blowing process by 20 ℃ by using a temperature model, so that the control can be effectively avoided.

6. Application of temperature model in controlling final slag alkalinity

The high alkalinity of the final slag can cause a series of vicious problems of incomplete final slag, gun sticking, lime waste and the like, the slag alkalinity is always in a fluctuation state due to the fluctuation of the quality of the lime and the instability of the utilization coefficient of the lime, the slag alkalinity can be dynamically adjusted according to the utilization of the alkalinity in the temperature model, the alkalinity calculated by the temperature model is observed according to the terminal phosphorus condition, if the terminal phosphorus component is low, the use amount of the lime is tried to be reduced, the alkalinity of 0.2 is reduced between heats, whether the reduction is continued or not is determined according to the component observation, the reduction is not carried out when the reduction is reduced to 2.2, and the lime consumption is low at the moment, so that the effect of reducing the slag charge consumption is completely achieved.

The present invention is not limited to the above embodiments, and any structural changes made under the teaching of the present invention shall fall within the scope of the present invention, which is similar or similar to the technical solutions of the present invention.

The techniques, shapes, and configurations not described in detail in the present invention are all known techniques.

Claims (1)

1. A method for controlling the process and end point temperature of a converter is characterized by comprising the following steps:

1) Comparing the temperature difference according to the physical heat and the chemical heat of the molten iron by comparing the upper and lower heats, and displaying the specific numerical value of the temperature difference on a control interface;

2) According to the compared temperature difference, the temperature which should be obtained by the current furnace is calculated through the specific value of the temperature of the previous furnace, and whether the reaction in the smelting process is normal is determined according to the quantized data of the process temperature;

3) And judging the reasonable slag alkalinity of the current furnace according to the end point components, dynamically adjusting the slag consumption, orderly reducing the slag alkalinity if the end point components of the furnace are low, and otherwise.