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CN-121977358-A - Control method for realizing waste heat recovery of annular cooler

CN121977358ACN 121977358 ACN121977358 ACN 121977358ACN-121977358-A

Abstract

The invention provides a control method for realizing the waste heat recovery of a circular cooler, which comprises the steps of calculating cooling air quantity required by a high temperature section according to a waste gas temperature set value of the high temperature section, a heat calculated value of a sinter block at a No.1 monitoring point, a heat calculated value of a sinter block at a No.2 monitoring point and a waste gas temperature of a middle temperature section, calculating cooling air quantity required by the middle temperature section according to the waste gas temperature of the low temperature section, the heat calculated value of the sinter block at the No.2 monitoring point, a set average ore temperature of the sinter block at a No.3 monitoring point and a heat set value, and calculating cooling air quantity required by the low temperature section according to the heat calculated value of the sinter block at the No.3 monitoring point and the set average ore temperature and the heat set value of the sinter block at a No.4 monitoring point. The control method provides parameter guidance for cooling air quantity adjustment of each temperature section, achieves the triple purposes of controllable cooling of the sinter, waste heat recycling and frequency conversion power saving, and effectively improves the heat energy utilization rate.

Inventors

  • CHEN LUYI
  • Mo Xuhong
  • QIU LIYUN
  • LI CHENXI

Assignees

  • 中冶长天国际工程有限责任公司
  • 中冶长天(长沙)智能科技有限公司

Dates

Publication Date
20260505
Application Date
20260204

Claims (10)

  1. 1. The control method for realizing the recovery of the waste heat of the ring cooler is characterized by comprising the steps of arranging a first circulating fan to convey waste gas of a middle temperature section to an air inlet of a high temperature section, arranging a second circulating fan to convey waste gas of a low temperature section to the air inlet of the middle temperature section, and arranging a high temperature section inlet, a middle and high temperature section juncture, a middle and low temperature section juncture and a low temperature section outlet of the ring cooler as 1#, 2#, 3# and 4# monitoring points in sequence, wherein the control method comprises the following steps: according to the exhaust gas temperature set value of the high temperature section Heat calculation of agglomerate block at No. 1 monitoring point Heat calculation of agglomerate block at No. 2 monitoring point Exhaust gas temperature in medium temperature section Calculating the cooling air quantity required by the high-temperature section ; According to the exhaust gas temperature of the low temperature section Heat calculation of agglomerate block at No. 2 monitoring point Setting average ore temperature of agglomerate at No. 3 monitoring point Heat set point Calculating the cooling air quantity required by the medium temperature section ; Calculated value according to heat quantity of agglomerate blocks at No. 3 monitoring point Setting average ore temperature of agglomerate at No. 4 monitoring point And heat set point Calculating the cooling air quantity required by the low-temperature section 。
  2. 2. The control method according to claim 1, characterized in that Indicating any one of No.1, no. 2, no.3 and No. 4 monitoring points, the agglomerate blocks at the monitoring points Calculated heat value at Expressed as: Wherein, the For monitoring points The quality of the agglomerate is that of the agglomerate, To sinter the specific heat capacity of the lump, For monitoring points The average ore temperature of the agglomerate is calculated, For the density of the sinter ore, For the inside radius of the agglomerate segments, For the outside radius of the agglomerate segments, Is the operation angular speed of the annular cooler, For monitoring points The average height of the agglomerate is the same, In order to achieve a peripheral rate of the material, For the time interval of division of the sinter.
  3. 3. The control method according to claim 2, wherein the average mine temperature at the # 1 monitoring point Surface average temperature measurement value equal to agglomerate block at No. 1 monitoring point ; The average mine temperatures at monitoring points # 2, # 3 and # 4 are expressed as: By using Any one of No. 2, no. 3 and No. 4 monitoring points is represented, and the monitoring points are represented Average ore temperature of sinter block Expressed as: Wherein, the Monitoring point for indicating agglomerate blocking A surface average temperature measurement at which, Representing monitoring points A cooling gradient at the position of the heat exchanger, Representing monitoring points The average height of the agglomerate is equal to the average height of the agglomerate; alternatively, adopt Any one of No. 2, no. 3 and No. 4 monitoring points is represented, and the monitoring points are represented Average ore temperature of sinter block The calculation method comprises the following steps: setting a scale factor Will monitor the point The sinter is divided into an upper layer block and a lower layer block, wherein the upper layer block is expressed as The lower layer blocks are represented as , wherein, , Representing monitoring points The average height of the agglomerate is equal to the average height of the agglomerate; Dividing the upper layer of blocks into equal parts along the height direction Sub-layers, the sum of the ore temperatures of the sub-layers Expressed as: dividing the lower layer of blocks into equal parts along the height direction Sub-layers, the sum of the ore temperatures of the sub-layers Expressed as: Then the monitoring point Average ore temperature of sinter block Expressed as: Wherein, the And The steps are the cutting step length, Monitoring point for indicating agglomerate blocking A surface average temperature measurement at which, As the coefficient related to the granularity coefficient, Is a constant of the material, and is a constant of the material, The wind speed of the cooling wind is indicated, Is that The mine temperature at the elevation location.
  4. 4. The control method according to claim 1, characterized in that the amount of power generation per unit time of the exhaust gas waste heat of the high temperature section is expressed as: Wherein, the The cooling air quantity input into the high temperature section is used, For the density of the exhaust gas, Is the specific heat capacity of the exhaust gas, For the air outlet temperature of the steam heated by the high-temperature section waste gas during power generation, In order for the power generation efficiency to be high, Is the power generation amount per unit time.
  5. 5. The control method according to any one of claims 1 to 4, wherein the cooling air quantity required for the high temperature section is calculated The method specifically comprises the following steps: the temperature of the cooling air input by the high-temperature section is calculated as The air quantity required in the process If the maximum air quantity of the first circulating fan Order in principle If the maximum air quantity of the first circulating fan The cooling air quantity of the high-temperature section which is needed to be supplemented by other blowers is calculated Order-making ; The temperature of the cooling air input by the high temperature section is When the required air quantity is needed Expressed as: air quantity required to be supplemented by other blowers Expressed as: Wherein, the For the density of the exhaust gas, Is the specific heat capacity of the exhaust gas, In order to be at the temperature of the environment, Is the utilization rate of heat.
  6. 6. The control method according to any one of claims 2 to 4, characterized in that the cooling air quantity required for the intermediate temperature section is calculated The method specifically comprises the following steps: The temperature of the cooling air input by the medium temperature section is calculated as The air quantity required in the process If the maximum air quantity of the second circulating fan Order in principle If the maximum air quantity of the second circulating fan The cooling air quantity of the middle temperature section which is needed to be supplemented by other blowers is calculated Order-making ; The temperature of the cooling air input by the medium temperature section is When the required air quantity is needed Expressed as: air quantity required to be supplemented by other blowers Expressed as: Wherein, the exhaust gas temperature of the middle temperature section is set as the value Expressed as: Heat setting value of agglomerate block at No. 3 monitoring point Expressed as: Wherein, the For the density of the exhaust gas, Is the specific heat capacity of the exhaust gas, For the utilization rate of the heat quantity, The average ore temperature of the agglomerate at the No. 2 monitoring point is calculated, Setting average ore temperature of agglomerate at 3# monitoring point, Is a coefficient of proportionality and is used for the control of the power supply, In order to be at the temperature of the environment, The average height of the agglomerate at the 3# monitoring point, The mass of the agglomerate at the monitoring point # 3 is determined.
  7. 7. The control method according to any one of claims 2 to 4, wherein the cooling air volume required for the low temperature section Expressed as: wherein the exhaust gas temperature set value of the low temperature section Expressed as: Heat setting value of agglomerate block at No. 4 monitoring point Expressed as: Wherein, the For the density of the exhaust gas, Is the specific heat capacity of the exhaust gas, For the utilization rate of the heat quantity, For the cooling air temperature input to the low temperature section, The average ore temperature of the agglomerate at the No. 3 monitoring point is calculated, Setting average ore temperature of agglomerate at No. 4 monitoring point, Is a coefficient of proportionality and is used for the control of the power supply, The average height of the agglomerate at the No. 4 monitoring point is calculated, The quality of the agglomerate at the monitoring point No. 4.
  8. 8. The control method according to claim 7, wherein the average ore temperature is set according to the agglomerate lump at the No. 4 monitoring point Actual average ore temperature The cooling air quantity required by the low temperature section is obtained through feedback regulation Expressed as: Wherein, the Is a proportionality coefficient.
  9. 9. The control method according to claim 1, wherein an average ore temperature is set Expressed as: Wherein, the The highest mine temperature set at the No. 4 monitoring point, Is a proportionality coefficient.
  10. 10. The control method according to claim 1, characterized in that Represents any one of a high temperature section, a medium temperature section and a low temperature section, Indicating the temperature range The cooling air quantity and the temperature of the current required cooling air quantity are equal to each other Setting a fluctuation range of exhaust gas temperature According to the temperature range Last cooling air quantity Temperature section Current calculation parameter back calculation temperature section Output exhaust gas temperature If (if) The current cooling air quantity is not required to be adjusted Otherwise, according to the temperature range Re-calculating cooling air quantity according to calculated parameters of (a) 。

Description

Control method for realizing waste heat recovery of annular cooler Technical Field The invention relates to the technical field of ring cooler control, in particular to a control method for realizing the recovery of waste heat of a ring cooler. Background Sintering is a fundamental link of the iron and steel industry, and provides a high-quality raw material for iron making. The sintering process is to bake the iron-containing material on a sintering machine at high temperature (less than or equal to 1400 ℃) after proportioning and mixing, so that the material is subjected to a series of physical and chemical changes. The air draft cooling in the sintering process is completed by an annular cooler (annular cooler), the annular cooler mainly comprises a feeding chute, a trolley, an air box, a discharging chute and other parts, the hot ore discharged by the sintering machine is cooled by means of air blowing or air draft, the cooling effect is related to the thickness of a hot ore layer and the uniformity of spreading, and the hot ore on the trolley is spread to be thinner and easier to cool with the same air quantity. The cooling process of the ring cooler is expected to be controllable, so that the sinter of each section is controlled within a proper temperature range until the temperature of the material at the outlet reaches below the set outlet temperature. In order to realize the cooling effect of the agglomerate, the air door is generally fully opened, the variable frequency fan is operated at high frequency, so that the waste heat power generation is influenced by the fluctuation of the temperature of the flue gas, the problem of low efficiency is caused, meanwhile, the cooling process in the annular cooler is uncontrollable, the subsequent cooling effect can only be manually estimated based on the ore temperature at the outlet of the annular cooler, and the problems of ultra-high ore temperature conveyor belts or watering and cooling are often caused, and the quality of the agglomerate is reduced. In view of the foregoing, there is a great need for a control method for implementing waste heat recovery of a circular cooler to solve the problems in the prior art. Disclosure of Invention The invention aims to provide a control method for realizing the recovery of waste heat of a circular cooler, which aims to solve the problems of large fluctuation of flue gas temperature and uncontrollable cooling of sinter in the circular cooler in the prior art of the waste heat power generation of the circular cooler, and the specific technical scheme is as follows: The control method for realizing the recovery of the waste heat of the annular cooler comprises the steps of arranging a first circulating fan to convey waste gas of a middle temperature section to an air inlet of a high temperature section, arranging a second circulating fan to convey waste gas of a low temperature section to the air inlet of the middle temperature section, and arranging 1# monitoring points, 2# monitoring points, 3# monitoring points and 4# monitoring points at the inlet of the high temperature section, the junction of the middle temperature section and the low temperature section of the annular cooler and at an outlet of the low temperature section in sequence, wherein the control method comprises the following steps: according to the exhaust gas temperature set value of the high temperature section Heat calculation of agglomerate block at No. 1 monitoring pointHeat calculation of agglomerate block at No. 2 monitoring pointExhaust gas temperature in medium temperature sectionCalculating the cooling air quantity required by the high-temperature section; According to the exhaust gas temperature of the low temperature sectionHeat calculation of agglomerate block at No. 2 monitoring pointSetting average ore temperature of agglomerate at No. 3 monitoring pointHeat set pointCalculating the cooling air quantity required by the medium temperature section; Calculated value according to heat quantity of agglomerate blocks at No. 3 monitoring pointSetting average ore temperature of agglomerate at No. 4 monitoring pointAnd heat set pointCalculating the cooling air quantity required by the low-temperature section。 Preferably, use is made ofIndicating any one of No.1, no. 2, no.3 and No. 4 monitoring points, the agglomerate blocks at the monitoring pointsCalculated heat value atExpressed as: Wherein, the For monitoring pointsThe quality of the agglomerate is that of the agglomerate,To sinter the specific heat capacity of the lump,For monitoring pointsThe average ore temperature of the agglomerate is calculated,For the density of the sinter ore,For the inside radius of the agglomerate segments,For the outside radius of the agglomerate segments,Is the operation angular speed of the annular cooler,For monitoring pointsThe average height of the agglomerate is the same,In order to achieve a peripheral rate of the material,For the time interval of divis