CN112452521A - Method for calibrating inlet air volume coefficient of medium-speed coal mill - Google Patents
Method for calibrating inlet air volume coefficient of medium-speed coal mill Download PDFInfo
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- CN112452521A CN112452521A CN202011225853.7A CN202011225853A CN112452521A CN 112452521 A CN112452521 A CN 112452521A CN 202011225853 A CN202011225853 A CN 202011225853A CN 112452521 A CN112452521 A CN 112452521A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
- B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
- B02C25/00—Control arrangements specially adapted for crushing or disintegrating
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F25/00—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume
- G01F25/10—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume of flowmeters
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Abstract
The invention discloses a method for calibrating an inlet air quantity coefficient of a medium-speed coal mill, which comprises the following steps of: 1) giving an air volume correction coefficient xi in a cold state; 2) carrying out a hot state air quantity calibration test of the medium-speed mill inlet air quantity measuring device, correcting a measured pressure difference delta P primary signal in PID through temperature T and static pressure P, multiplying a correction result by an air quantity correction coefficient xi, and taking the multiplied result as a measured air quantity value Q of the mill inlet air quantity measuring device; 3) under different air quantities Q and different opening degrees k of the cold air door, a hot state air quantity calibration test is carried out on the air quantity measuring device by adopting a univariate orthogonal method to obtain a fresh air quantity correction coefficient xi ' of the hot state mill inlet air quantity measuring device, the fresh air quantity correction coefficient xi ' of the hot state mill inlet air quantity measuring device is used for replacing the air quantity correction coefficient xi, and the coal mill air quantity Q ' is obtained through calculation.
Description
Technical Field
The invention belongs to the technical field of control of medium-speed coal mills of large coal-electric units, and relates to a method for calibrating an inlet air volume coefficient of a medium-speed coal mill.
Background
In a large coal-fired unit boiler, a plurality of medium-speed coal mills are matched, accurate measurement of inlet air quantity of the medium-speed coal mills is the premise of ensuring that a pulverizing system operates according to an optimal air-coal ratio curve and a primary air rate, and inaccurate measurement of the inlet air quantity of the medium-speed coal mills can cause the problems of mill blockage, high power consumption of a primary fan, coarse pulverized coal, high primary air rate, unstable combustion under low load, poor low-nitrogen effect, automatic operation failure of the air quantity and the like, so that accurate measurement of the inlet air quantity of the mill is of great importance.
The requirement of accurate measurement of the inlet air quantity of the medium-speed coal mill can simultaneously meet two conditions that the measuring device is reliable and the installation position meets the requirement of a straight pipe section. Under the prior art, a mill inlet air volume device is mature, but is limited by a compact installation space on site, the installation position of an inlet air volume measuring device of a medium-speed coal mill does not meet the requirement of a straight pipe section, the installation section of the inlet air volume measuring device of the current medium-speed coal mill has the problems of uneven speed field and uneven temperature field, and the larger the unit is, the worse the uniformity of the flow field and the temperature field is. The air volume calibration coefficient corresponding to the medium-speed mill inlet air volume measuring device under different air volumes is poor in linearity and greatly influenced by the cold air door, the main reason of the poor air volume calibration coefficient is that the speed field is not uniform, and the influence of the cold air door is large and mainly embodied as follows: the cold state measurement linearity of the coal mill inlet air quantity measuring device is good, but the hot state cannot accurately measure the cold and hot mixed air quantity, and even the trend that the air quantity of the coal mill inlet dial plate changes reversely and fluctuates greatly along with the cold air adjusting door of the coal mill inlet under the hot state operation condition can occur. The prior art for the above problems mainly includes:
1) aiming at the problem of uneven speed field, the main solutions are as follows: the array type air volume measuring device reduces the influence of the nonuniformity of the speed field by arranging differential pressure measuring signal points in an array type; moving the air quantity measuring device to a straight pipe section farther away from the elbow; and a guide plate is added at the elbow, so that the uniformity of the velocity field of the measuring section is improved.
2) Aiming at the problem of uneven temperature field, the main solutions are as follows: a set of device for accelerating the mixing speed of cold air and hot air is added at the mixing position of the cold air and the hot air, the device can realize the quick mixing of the cold air and the hot air by sacrificing a part of primary air pressure heads, and various technical means such as a grid type and a cold air uniform distribution type are adopted, so that the mixing speed of the cold air and the hot air is increased.
At present, air volume measuring devices are basically array type, the problem of uneven speed field can be basically solved through optimization of positions of the air volume measuring devices, but the problem of uneven temperature field is solved, the traditional method is usually required to be modified by stopping grinding, and primary air resistance is increased. The method for calibrating the air quantity coefficient of the inlet of the medium-speed coal mill is provided, primary air resistance is not increased, grinding stop and maintenance are not needed, only a test calibration method is adopted, the cost is far lower than that of reconstruction, and the accuracy of measurement is improved.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a method for calibrating an inlet air quantity coefficient of a medium-speed coal mill, which can improve the measurement accuracy of an air quantity measuring device.
In order to achieve the aim, the method for calibrating the air volume coefficient of the inlet of the medium-speed coal mill comprises the following steps:
1) carrying out a cold state air quantity calibration test of the medium-speed mill inlet air quantity measuring device, and giving an air quantity correction coefficient xi in a cold state;
2) carrying out a hot state air quantity calibration test of the medium-speed mill inlet air quantity measuring device, correcting a measured pressure difference delta P primary signal in PID through temperature T and static pressure P, multiplying a correction result by an air quantity correction coefficient xi, and taking the multiplied result as a measured air quantity value Q of the mill inlet air quantity measuring device;
3) under different air quantities Q and different opening degrees k of the cold air door, a thermal state air quantity calibration test is carried out on the air quantity measuring device by adopting a univariate orthogonal method to obtain a fresh air quantity correction coefficient xi ' of the grinding inlet air quantity measuring device under the thermal state, and the fresh air quantity correction coefficient xi ' of the grinding inlet air quantity measuring device under the thermal state is used for replacing the air quantity correction coefficient xi to calculate to obtain the air quantity Q ' of the coal mill.
Q＝f(ΔP，P，T,ξ)。
Q'＝f(ΔP，P，T,ξ')。
ξ'＝f(Q，k)。
The invention has the following beneficial effects:
according to the calibration method of the medium speed coal mill inlet air volume coefficient, the air volume correction coefficients of the medium speed coal mill inlet air volume measuring device under different air volumes are obtained in a cold state during specific operation, the consistency of the air volume correction coefficients is good, and the air volume correction coefficients are used as the original air volume correction coefficients in the PID of the mill inlet air volume calculation; in a thermal state, carrying out thermal state air volume calibration tests under different mill inlet air volumes and different cold air door opening degrees to obtain a new air volume correction coefficient function based on the mill inlet air volume and the cold air door opening degree, replacing the new air volume correction coefficient with the original mill inlet air volume to calculate an original air volume correction coefficient in PID, and multiplying a section average differential pressure signal obtained by the array type air volume measuring device by the new air volume correction coefficient after temperature and pressure correction in actual operation to realize accurate measurement of the air volume measuring device.
Drawings
FIG. 1 is a flow chart of the present invention.
Detailed Description
The invention is described in further detail below with reference to the accompanying drawings:
referring to fig. 1, the method for calibrating the air volume coefficient at the inlet of the medium speed coal mill comprises the following steps:
1) carrying out a cold state air quantity calibration test of the medium-speed mill inlet air quantity measuring device to obtain an air quantity correction coefficient xi in a cold state;
through a cold state air volume calibration test, an air volume correction coefficient xi in a cold state is given, and generally, under the condition that the position of a measuring device is proper for an array type air volume measuring device, the air volume correction coefficient xi in different air volumes Q is good in consistency and generally is a fixed value;
2) thermal state air quantity calibration test for medium-speed mill inlet air quantity measuring device
In a hot state, a measured primary signal of differential pressure delta P is corrected through temperature T and static pressure P in PID, a correction result is multiplied by an air volume correction coefficient xi, and the multiplication result is used as an air volume value Q measured by an inlet grinding air volume measuring device, namely Q is f (delta P, P, T and xi), wherein the static pressure P has little influence on air volume correction, but a temperature value T has great influence, in the hot state, a measured section temperature field is not uniform due to non-uniform mixing of cold air and hot air, the temperature at the section of the air volume measuring device is often measured by a single-point thermocouple, and the single-point temperature value is difficult to represent the average temperature value of the whole section, so that the inlet grinding air volume measurement is not accurate. The opening k of the cold air door has direct influence on the uniformity of a temperature field, so that the air volume correction coefficient xi' of the air volume measuring device is greatly influenced;
3) under different air quantities Q and different opening degrees k of the cold air door, a hot state air quantity calibration test is carried out on the air quantity measuring device by adopting a univariate orthogonal method to obtain a new air quantity correction coefficient xi 'of the grinding inlet air quantity measuring device under a hot state, wherein xi' ═ f (Q, k), and a function xi '═ f (Q, k) is used for replacing an air quantity correction coefficient xi in a PID (proportion integration differentiation) calculated by an air quantity value Q of an original grinding inlet air quantity device to calculate and obtain the air quantity Q' of the coal mill, and the function relation is Q '═ f (delta P, P, T, xi').
Claims (4)
1. A calibration method for the air volume coefficient of an inlet of a medium speed coal mill is characterized by comprising the following steps:
1) carrying out a cold state air quantity calibration test of the medium-speed mill inlet air quantity measuring device, and giving an air quantity correction coefficient xi in a cold state;
2) carrying out a hot state air quantity calibration test of the medium-speed mill inlet air quantity measuring device, correcting a measured pressure difference delta P primary signal in PID through temperature T and static pressure P, multiplying a correction result by an air quantity correction coefficient xi, and taking the multiplied result as a measured air quantity value Q of the mill inlet air quantity measuring device;
3) under different air quantities Q and different opening degrees k of the cold air door, a thermal state air quantity calibration test is carried out on the air quantity measuring device by adopting a univariate orthogonal method to obtain a fresh air quantity correction coefficient xi ' of the grinding inlet air quantity measuring device under the thermal state, and the fresh air quantity correction coefficient xi ' of the grinding inlet air quantity measuring device under the thermal state is used for replacing the air quantity correction coefficient xi to calculate to obtain the air quantity Q ' of the coal mill.
2. The method for calibrating the inlet air volume coefficient of the medium speed coal mill according to claim 1, wherein Q ═ f (Δ P, T, ξ).
3. The method for calibrating the inlet air volume coefficient of the medium speed coal mill according to claim 1, wherein Q '═ f (Δ P, T, ξ').
4. The method for calibrating the inlet air volume coefficient of the medium speed coal mill according to claim 1, wherein ξ ═ f (Q, k).
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113108308A (en) * | 2021-04-09 | 2021-07-13 | 苏州西热节能环保技术有限公司 | Method for adjusting wall temperature of flash combustion boiler after low-load abrasion stop |
| CN114178036A (en) * | 2021-10-15 | 2022-03-15 | 广东红海湾发电有限公司 | Inlet primary air volume and primary air pressure control method of coal mill |
Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0429761A (en) * | 1990-05-28 | 1992-01-31 | Mitsubishi Heavy Ind Ltd | Apparatus for controlling airflow rate of coal pulverizer |
| CN103925605A (en) * | 2014-04-04 | 2014-07-16 | 西安西热锅炉环保工程有限公司 | High-moisture lignite medium-speed coal mill pulverizing system heating primary air through pulverized coal burning |
| CN104949717A (en) * | 2015-06-29 | 2015-09-30 | 南京博沃科技发展有限公司 | Primary air flow measuring system for entrance of coal mill |
| CN105571653A (en) * | 2015-12-17 | 2016-05-11 | 广东电网有限责任公司电力科学研究院 | Air volume measurement method and system for coal pulverizer |
| CN105699040A (en) * | 2014-11-28 | 2016-06-22 | 国家电网公司 | Automatic verification method and system of coal mill inlet air quantity measuring apparatus |
| CN205435977U (en) * | 2016-03-17 | 2016-08-10 | 苏州西热节能环保技术有限公司 | Wind mixed flow and flow straightener in circular wind channel of coal pulverizer entry |
| CN107262261A (en) * | 2017-07-12 | 2017-10-20 | 华北电力大学（保定） | A kind of coal pulverizer air quantity control method for adapting to fired power generating unit Ultra-low load operation |
| CN107514629A (en) * | 2017-08-25 | 2017-12-26 | 国网安徽省电力公司电力科学研究院 | A kind of cold and hot primary air flow bearing calibration of fired power generating unit |
| CN207247264U (en) * | 2017-04-26 | 2018-04-17 | 西安热工研究院有限公司 | The air quantity and coal dust amount distribution regulating device of a kind of baffle automatic adjustment |
| CN108106679A (en) * | 2017-12-08 | 2018-06-01 | 重庆大唐国际石柱发电有限责任公司 | A kind of measuring method and system of power station coal pulverizer inlet air quantity |
| CN111135944A (en) * | 2019-12-06 | 2020-05-12 | 华北电力科学研究院有限责任公司 | Method and system for determining coal blockage of coal mill of power station boiler |
| CN111151367A (en) * | 2020-01-18 | 2020-05-15 | 华能国际电力股份有限公司井冈山电厂 | Coal mill and method for analyzing primary air volume thereof |
| CN111664443A (en) * | 2020-05-28 | 2020-09-15 | 国网河北省电力有限公司电力科学研究院 | Cold state research method for adjusting smoke temperature deviation of two sides of tetragonal tangential boiler |
| CN111853851A (en) * | 2020-07-31 | 2020-10-30 | 国网安徽省电力有限公司电力科学研究院 | Primary air speed correction and leveling method for coal-fired thermal power generating unit boiler |
| CN111853846A (en) * | 2020-08-21 | 2020-10-30 | 西安热工研究院有限公司 | System for improving output of medium-speed coal mill by pre-drying furnace smoke and working method thereof |
-
2020
- 2020-11-05 CN CN202011225853.7A patent/CN112452521B/en active Active
Patent Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0429761A (en) * | 1990-05-28 | 1992-01-31 | Mitsubishi Heavy Ind Ltd | Apparatus for controlling airflow rate of coal pulverizer |
| CN103925605A (en) * | 2014-04-04 | 2014-07-16 | 西安西热锅炉环保工程有限公司 | High-moisture lignite medium-speed coal mill pulverizing system heating primary air through pulverized coal burning |
| CN105699040A (en) * | 2014-11-28 | 2016-06-22 | 国家电网公司 | Automatic verification method and system of coal mill inlet air quantity measuring apparatus |
| CN104949717A (en) * | 2015-06-29 | 2015-09-30 | 南京博沃科技发展有限公司 | Primary air flow measuring system for entrance of coal mill |
| CN105571653A (en) * | 2015-12-17 | 2016-05-11 | 广东电网有限责任公司电力科学研究院 | Air volume measurement method and system for coal pulverizer |
| CN205435977U (en) * | 2016-03-17 | 2016-08-10 | 苏州西热节能环保技术有限公司 | Wind mixed flow and flow straightener in circular wind channel of coal pulverizer entry |
| CN207247264U (en) * | 2017-04-26 | 2018-04-17 | 西安热工研究院有限公司 | The air quantity and coal dust amount distribution regulating device of a kind of baffle automatic adjustment |
| CN107262261A (en) * | 2017-07-12 | 2017-10-20 | 华北电力大学（保定） | A kind of coal pulverizer air quantity control method for adapting to fired power generating unit Ultra-low load operation |
| CN107514629A (en) * | 2017-08-25 | 2017-12-26 | 国网安徽省电力公司电力科学研究院 | A kind of cold and hot primary air flow bearing calibration of fired power generating unit |
| CN108106679A (en) * | 2017-12-08 | 2018-06-01 | 重庆大唐国际石柱发电有限责任公司 | A kind of measuring method and system of power station coal pulverizer inlet air quantity |
| CN111135944A (en) * | 2019-12-06 | 2020-05-12 | 华北电力科学研究院有限责任公司 | Method and system for determining coal blockage of coal mill of power station boiler |
| CN111151367A (en) * | 2020-01-18 | 2020-05-15 | 华能国际电力股份有限公司井冈山电厂 | Coal mill and method for analyzing primary air volume thereof |
| CN111664443A (en) * | 2020-05-28 | 2020-09-15 | 国网河北省电力有限公司电力科学研究院 | Cold state research method for adjusting smoke temperature deviation of two sides of tetragonal tangential boiler |
| CN111853851A (en) * | 2020-07-31 | 2020-10-30 | 国网安徽省电力有限公司电力科学研究院 | Primary air speed correction and leveling method for coal-fired thermal power generating unit boiler |
| CN111853846A (en) * | 2020-08-21 | 2020-10-30 | 西安热工研究院有限公司 | System for improving output of medium-speed coal mill by pre-drying furnace smoke and working method thereof |
Non-Patent Citations (3)
| Title |
|---|
| 刘正强、员盼锋、吕宏彪、杨培军: "刘正强、员盼锋、吕宏彪、杨培军", 《热力发电》 * |
| 蔡培、窦文杰: "某"W"型锅炉炉效低的综合治理", 《电力科技与环保》 * |
| 闫顺林、韩韦、王皓轩、张永昇、刘洋: "组合式一次风管对锅炉运行的影响分析", 《动力工程学报》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113108308A (en) * | 2021-04-09 | 2021-07-13 | 苏州西热节能环保技术有限公司 | Method for adjusting wall temperature of flash combustion boiler after low-load abrasion stop |
| CN113108308B (en) * | 2021-04-09 | 2022-04-19 | 苏州西热节能环保技术有限公司 | Method for adjusting wall temperature of flash combustion boiler after low-load abrasion stop |
| CN114178036A (en) * | 2021-10-15 | 2022-03-15 | 广东红海湾发电有限公司 | Inlet primary air volume and primary air pressure control method of coal mill |
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