CN118026558A - Cement calcination convection circulation exhaust monitoring management system based on Internet of things - Google Patents

Abstract

The present invention belongs to the technical field of cement calcination management, and specifically, relates to a cement calcination convection circulation exhaust monitoring and management system based on the Internet of Things. The present invention determines whether the cement calcination environment is in a micro-positive pressure convection circulation state based on relevant air pressure parameters of the cement calcination environment, and then specifically analyzes the actual calcination efficiency of the cement calcination environment under the current micro-positive pressure convection circulation state from the two aspects of economic energy consumption optimization and cement calcination quality, and uses it as a basis for adjusting the cement calcination environment parameters. While ensuring that the cement calcination environment maintains a micro-positive pressure state, combined with the in-kiln monitoring parameters of the cement calcination environment, the adjustment requirements of the airflow flow rate and airflow velocity and the specific adjustment parameters are comprehensively considered, which not only contributes to the stable operation of the cement calcination environment, but also optimizes energy utilization efficiency, reduces energy consumption, and thus effectively improves the quality and output of cement clinker.

Description

A cement calcination convection circulation ventilation monitoring and management system based on the Internet of Things

Technical Field

The present invention belongs to the technical field of cement calcination management, and in particular, relates to a cement calcination convection circulation exhaust monitoring and management system based on the Internet of Things.

Background technique

Cement calcination is a key link in cement production, which directly affects the quality and production efficiency of the product. In the traditional cement calcination process, negative pressure ventilation is often used, but due to its many disadvantages such as unstable air flow in the furnace, uneven clinker distribution and low thermal efficiency, the micro-positive pressure convection circulation ventilation system has gradually attracted attention.

Compared with the traditional negative pressure method, the micro-positive pressure convection circulation ventilation can better control the airflow distribution in the furnace, making the clinker more evenly distributed during the calcination process. However, it is not enough to use only the micro-positive pressure convection circulation ventilation system. In order to ensure the stable operation of the system and maximize its benefits, an effective monitoring and management system is needed for real-time monitoring and data analysis. The cement calcination convection circulation ventilation monitoring and management system based on the Internet of Things came into being.

Although the existing technology for monitoring and managing convection circulation exhaust of cement calcination meets certain requirements, it still has limitations, specifically: 1. The existing technology lacks automated monitoring of the micro-positive pressure convection circulation state of the cement calcination environment, and focuses on investigating the micro-positive pressure state of the cement calcination environment, ignoring whether the airflow in the cement calcination environment is effectively convectively circulated, which is not enough to ensure the overall optimization of the calcination environment and the improvement of product quality.

2. The existing technology is relatively lacking in calcination efficiency evaluation for cement calcination environment. Even if the cement calcination environment is in a state of micro-positive pressure convection circulation, it is impossible to timely determine whether the current state truly and effectively promotes cement calcination. As a result, when cement calcination problems occur, it is impossible to quickly find the causes and make adjustments, thus affecting production efficiency and product quality.

3. The existing technology for adjusting the environmental parameters of cement calcination is relatively superficial. It not only fails to deeply explore the intrinsic relationship between key parameters such as air flow rate and air velocity and the calcination state in the cement rotary kiln, but also fails to reasonably and effectively consider the impact of the adjustment of the environmental parameters of cement calcination on the micro-positive pressure state, which may lead to changes in the air pressure of the cement calcination environment, and then the originally stable micro-positive pressure state may become invalid, thereby affecting the stability and efficiency of cement calcination.

Summary of the invention

In order to overcome the shortcomings of the background technology, the embodiment of the present invention provides a cement calcination convection circulation exhaust monitoring and management system based on the Internet of Things, which can effectively solve the problems involved in the above-mentioned background technology.

The purpose of the present invention can be achieved through the following technical solutions: a cement calcination convection circulation exhaust monitoring and management system based on the Internet of Things, including: a convection circulation state analysis module, used to collect relevant air pressure parameters of the cement calcination environment, and determine whether the cement calcination environment is in a micro-positive pressure convection circulation state. If it is determined that the cement calcination environment is in a micro-positive pressure convection circulation state, the cement calcination benefit evaluation module is executed, otherwise the cement calcination environment abnormal feedback module is executed.

The cement calcination benefit evaluation module is used to collect relevant calcination parameters of the cement calcination environment and evaluate the calcination benefit coefficient of the cement calcination environment. If it is greater than or equal to the preset reasonable calcination benefit coefficient, the normal feedback module of the cement calcination environment is executed, otherwise the cement calcination environment adjustment module is executed.

The cement calcining environment adjustment module is used to collect the in-kiln monitoring parameters of the cement calcining environment, analyze the adjustment requirements and corresponding adjustment parameters of the air flow rate and air velocity in the cement rotary kiln, and make corresponding adjustments accordingly.

The cement calcining environment abnormality feedback module is used to provide abnormal feedback of the cement calcining environment.

The normal feedback module of cement calcining environment is used for providing normal feedback of cement calcining environment.

The cloud database is used to store the qualified range of air flow velocity and air flow rate in the cement rotary kiln, store the standard color grayscale value of specific cement clinker output, store the reasonable calcination temperature value, reasonable calcination oxygen content and reasonable material flow rate of each area in the cement rotary kiln, store the reasonable calcination temperature difference between adjacent areas in the cement rotary kiln, and store the pressure change value of the cement calcination environment corresponding to the unit air flow velocity.

Preferably, the relevant air pressure parameters include the kiln mouth air pressure at each set time point within the set time period of the cement rotary kiln. and kiln tail gas pressure/> The gas pressure at the pipe outlet at each set time point within the set time period of the flue gas circulation pipe/> and tail gas pressure/> Wherein, i is the number of each set time point in the set time period, i=1, 2, ..., a.

The relevant calcination parameters include coal consumption, electricity consumption, cement clinker output and cement clinker production area image within a set time period.

The monitoring parameters in the kiln include the preset air flow per unit time, the preset flue gas flow per unit time and the preset air flow velocity at the kiln mouth of the cement rotary kiln, the temperature value at each set time point in the set time period in each area of the cement rotary kiln, the material flow rate and the oxygen content.

Preferably, the determination of whether the cement calcining environment is in a slightly positive pressure convection circulation state comprises: calculating the head and tail pressure differences of the cement rotary kiln and the flue gas circulation pipeline at each set time point within a set time period according to relevant air pressure parameters of the cement calcining environment, and recording them as

Calculate the average air pressure at each set time point within the set time period of the cement calcination environment

When satisfied When the condition is met, it is determined that the cement calcining environment is in a state of slightly positive pressure convection circulation; otherwise, it is determined that the cement calcining environment is not in a state of slightly positive pressure convection circulation, wherein _y0 is the preset atmospheric standard pressure, y′ and y″ are respectively the minimum allowable deviation value and the maximum allowable deviation value between the cement calcining environment pressure and the atmospheric standard pressure under the preset slightly positive pressure convection circulation state, and 0＜y′＜y″.

Preferably, the evaluation of the calcination efficiency coefficient of the cement calcination environment includes: extracting the coal consumption _mcoal , electricity consumption _melectricity and cement clinker output within a set time period from the relevant calcination parameters of the cement calcination environment By formula The economic energy consumption coefficient of the cement calcining environment within the set time period is obtained, wherein k ₁ and k ₂ are respectively the reasonable thresholds of the coal consumption rate and the electricity consumption rate of the preset cement calcining environment under the state of micro-positive pressure convection circulation.

Extract the cement clinker production area image within the set time period in the relevant calcination parameters of the cement calcination environment, identify and segment the contour area of each cement clinker in the image, mark it as the surface image of each cement clinker, analyze the basic quality evaluation coefficient δ _j of each cement clinker, where j is the number of each cement clinker, j=1,2,...,n, calculate the calcination quality coefficient β ₂ within the set time period of the cement calcination environment, Where δ ₀ is the preset reasonable threshold value of the cement clinker basic quality assessment coefficient, e is a natural constant, and n is the amount of cement clinker.

By formula The calcination efficiency coefficient of cement calcination environment is obtained, where/> They are respectively the corresponding weight proportions of the economic energy consumption coefficient and the calcination quality coefficient within the preset cement calcination environment setting time period.

Preferably, the analysis of the basic quality evaluation coefficient of each cement clinker includes: performing preprocessing and binarization on the surface images of each cement clinker, obtaining the grayscale difference value x _jq between each pixel in the surface image of each cement clinker and its horizontally adjacent pixel, wherein q is the number of each pixel in the surface image of the cement clinker, q=1, 2, ..., p, calculating the basic flatness h _j of each cement clinker, Where _x0 is the preset reasonable grayscale difference threshold between horizontally adjacent pixels.

The surface images of each cement clinker are further converted into RGB color space to obtain the color grayscale value g _jq of each pixel in the surface image of each cement clinker. Combined with the standard color grayscale value g ₀ of the specific cement clinker output stored in the cloud database, the basic color standardization degree s _j of each cement clinker is calculated. Where Δg is the preset color grayscale reasonable deviation threshold, and p is the number of pixels in the cement clinker surface image.

By identifying the crack features in the surface image of each cement clinker within the set time period of cement calcination, the length l _jr of each crack on the surface of each cement clinker is obtained, where r is the number of each crack on the surface of the cement clinker, r = 1, 2, ..., w, and the basic defect degree index f _j of each cement clinker is calculated.

Then by the formula The basic quality assessment coefficient of each cement clinker is obtained.

Preferably, the analyzing the adjustment demand of the airflow rate in the cement rotary kiln includes: calculating the airflow rate qualification ψ in the cement rotary kiln according to the temperature value t _ib and the oxygen content u _ib at each set time point in the set time period in each area in the cement rotary kiln in the kiln monitoring parameters of the cement calcining environment, wherein b is the number of each area in the cement rotary kiln, b=1, 2, ..., d, in combination with the reasonable calcination temperature value t ₀ and the reasonable calcination oxygen content u ₀ of each area in the cement rotary kiln stored in the cloud database, Where a is the number of set time points in the set time period.

The upper limit value ψ _max and the lower limit value ψ _min of the qualified range of the airflow flow in the cement rotary kiln stored in the cloud database are extracted. If ψ _min ≤ ψ ≤ ψ _max , it means that there is no need to adjust the airflow flow in the cement rotary kiln. Otherwise, it means that there is a need to adjust the airflow flow in the cement rotary kiln.

Preferably, the adjustment parameters of the airflow rate in the cement rotary kiln are analyzed, including: extracting the preset air flow rate per unit time _c1 and the preset flue gas flow rate per unit time _c2 at the kiln mouth of the cement rotary kiln from the kiln monitoring parameters of the cement calcining environment, accumulating them as the mixed airflow rate per unit time at the kiln mouth of the cement rotary kiln, and calculating the mixed airflow rate per unit time by the formula The circulating air input ratio per unit time at the cement rotary kiln mouth is obtained.

If ψ＞ψ _max , then according to the formula The circulating air input increase ratio per unit time of the cement rotary kiln mouth is obtained, π is 180°, and its product with the mixed airflow flow per unit time of the cement rotary kiln mouth is used as the increased flue gas recovery flow per unit time of the flue gas circulation pipeline mouth and the reduced air input flow per unit time of the cement rotary kiln mouth.

If ψ＜ψ _min , then according to the formula The circulating air reduction ratio per unit time of the cement rotary kiln mouth is obtained, and its product with the mixed airflow flow per unit time of the cement rotary kiln mouth is used as the flue gas recovery reduction flow per unit time of the flue gas circulation pipeline mouth and the air input increase flow per unit time of the cement rotary kiln mouth.

Preferably, the analyzing the adjustment demand of the airflow velocity in the cement rotary kiln includes: extracting the reasonable calcination temperature difference Δt and the reasonable material flow rate v ₀ of adjacent areas in the cement rotary kiln stored in the cloud database according to the temperature value t _ib and the material flow rate v _ib at each set time point in the set time period in each area in the cement rotary kiln in the kiln monitoring parameters of the cement calcining environment, and calculating the airflow velocity qualification ζ in the cement rotary kiln, Wherein _ti(b-1) is the temperature value at the i-th set time point within the set time period of the b-1-th area in the cement rotary kiln.

The upper limit value ζ _max and the lower limit value ζ _min of the qualified range of the air flow velocity in the cement rotary kiln stored in the cloud database are extracted. If ζ _mni ≤ζ ≤ζ _max , it means that there is no need to adjust the air flow velocity in the cement rotary kiln. Otherwise, it means that there is a need to adjust the air flow velocity in the cement rotary kiln.

Preferably, the analysis of the adjustment parameters of the airflow velocity in the cement rotary kiln includes: extracting the preset airflow velocity τ at the kiln mouth of the cement rotary kiln from the kiln monitoring parameters of the cement calcining environment, and obtaining the average air pressure of the cement calcining environment at the current time point when.

If ζ＞ζ _max , the pressure change value of cement calcination environment corresponding to the unit air flow rate stored in the cloud database By formula/> The limited downward adjustment flow rate of the air flow velocity in the cement rotary kiln is obtained, and then the _downward adjustment flow rate τ of the air flow velocity in the cement rotary kiln is calculated.

If ζ＜ζ _min , then according to the formula The limited upward adjustment flow rate of the air flow velocity in the cement rotary kiln is obtained, and then the upward adjustment flow rate τ of the air flow velocity in the cement rotary kiln _is calculated.

Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: (1) The present invention uses the relevant air pressure parameters of the cement calcining environment to comprehensively determine whether the cement calcining environment is in a micro-positive pressure convection circulation state based on the head and tail air pressure difference at each set time point in the set time period of the cement rotary kiln and the flue gas circulation duct, and the average air pressure at each set time point in the set time period of the cement calcining environment. This not only ensures that the cement calcining environment is in a micro-positive pressure state, but also effectively understands the airflow direction of the cement rotary kiln and the flue gas circulation duct, thereby ensuring the scientificity and accuracy of the judgment result, and laying a foundation for the subsequent calcination benefit evaluation of the cement calcining environment.

(2) The present invention comprehensively evaluates the calcination efficiency coefficient of the cement calcination environment from two aspects: the economic energy consumption coefficient and the calcination quality coefficient within a set time period of the cement calcination environment, and rationally examines the optimization effect of the current micro-positive pressure convection circulation state on the coal consumption, electricity consumption and the actual calcination quality of cement clinker, so as to provide real-time data support and decision-making basis for the subsequent adjustment of cement calcination environment parameters.

(3) The present invention sets the image of the cement clinker production area within a set time period, and rationally analyzes the basic flatness, basic color compliance and basic defect index of the cement clinker from the grayscale features, color features and image crack features of the pixels, which helps to comprehensively and accurately evaluate the calcination quality of the cement clinker, while effectively improving the evaluation efficiency of the calcination quality of the cement clinker.

(4) The present invention effectively analyzes the adjustment requirements and specific adjustment directions of the air flow rate from two aspects of the temperature and oxygen content in the cement rotary kiln. While ensuring that the mixed air flow rate at the kiln mouth of the cement rotary kiln remains unchanged, the circulating air input ratio is dynamically adjusted, thereby ensuring that the slightly positive pressure state in the cement calcining environment remains unchanged, thereby optimizing energy utilization efficiency while reducing energy consumption, and helping to improve product quality and output.

(5) The present invention reasonably considers the adjustment requirements and specific adjustment direction of the air flow rate from two aspects of the temperature difference and material flow rate in the cement rotary kiln. Within the allowable fluctuation range of the air pressure in the cement calcining environment, the air flow rate is effectively adjusted while maintaining a slightly positive pressure state in the cement calcining environment, which helps to maintain the stability of the calcining environment, thereby reducing production costs and improving the quality of cement calcining.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

FIG. 1 is a schematic diagram of module connection of the present invention.

FIG. 2 is a schematic diagram of the cement calcining environment structure of the present invention.

Figure numerals: 1. Cement rotary kiln mouth; 2. Flue gas circulation duct mouth; 3. Cement rotary kiln tail; 4. Flue gas circulation duct tail.

Detailed ways

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

1 , the present invention provides a cement calcination convection circulation exhaust monitoring and management system based on the Internet of Things, including: a convection circulation state analysis module, a cement calcination benefit evaluation module, a cement calcination environment adjustment module, a cement calcination environment abnormal feedback module, a cement calcination environment normal feedback module and a cloud database.

The convection circulation state analysis module is respectively connected to the cement calcination benefit evaluation module and the cement calcination environment abnormal feedback module, the cement calcination benefit evaluation module is respectively connected to the cement calcination environment adjustment module and the cement calcination environment normal feedback module, and the cloud database is respectively connected to the cement calcination benefit evaluation module and the cement calcination environment adjustment module.

The convection circulation state analysis module is used to collect relevant air pressure parameters of the cement calcination environment and determine whether the cement calcination environment is in a slightly positive pressure convection circulation state. If it is determined that the cement calcination environment is in a slightly positive pressure convection circulation state, the cement calcination benefit evaluation module is executed, otherwise the cement calcination environment abnormal feedback module is executed.

Specifically, the relevant air pressure parameters include the kiln outlet air pressure at each set time point within the set time period of the cement rotary kiln. and kiln tail gas pressure/> The gas pressure at the pipe outlet at each set time point within the set time period of the flue gas circulation pipe/> and tail gas pressure/> Wherein, i is the number of each set time point in the set time period, i=1, 2, ..., a.

It should be noted that the pipe opening of the above-mentioned flue gas circulation pipeline is close to the kiln tail side of the cement rotary kiln, and the pipe tail of the flue gas circulation pipeline is close to the kiln mouth side of the water machine rotary kiln, as shown in Figure 2 for details.

It should also be noted that the relevant air pressure parameters of the above-mentioned cement calcining environment are obtained through high-temperature resistant air pressure sensors arranged at the kiln mouth and kiln tail of the cement rotary kiln and at the pipe mouth and pipe tail of the flue gas circulation duct.

Specifically, the determination of whether the cement calcining environment is in a slightly positive pressure convection circulation state includes: according to the relevant air pressure parameters of the cement calcining environment, respectively calculating the head and tail air pressure differences of the cement rotary kiln and the flue gas circulation pipeline at each set time point within the set time period, recorded as

Calculate the average air pressure at each set time point within the set time period of the cement calcination environment

When satisfied When the condition is met, it is determined that the cement calcining environment is in a state of slightly positive pressure convection circulation; otherwise, it is determined that the cement calcining environment is not in a state of slightly positive pressure convection circulation, wherein _y0 is the preset atmospheric standard pressure, y′ and y″ are respectively the minimum allowable deviation value and the maximum allowable deviation value between the cement calcining environment pressure and the atmospheric standard pressure under the preset slightly positive pressure convection circulation state, and 0＜y′＜y″.

It should be noted that the above The conditions are based on the following: when the cement calcining environment is in a convection circulation state, the air flow initially flows from the cement rotary kiln mouth to the kiln tail, during which flue gas is generated. A fan and other equipment are used to extract part of the flue gas at the kiln tail to the flue gas circulation pipe mouth, and the flue gas flow then flows from the flue gas circulation pipe mouth to the pipe tail, and the pipe tail of the flue gas circulation pipe is connected to the cement rotary kiln mouth, and the recovered flue gas is mixed with the air flow at the cement rotary kiln mouth to achieve heat recovery. Since the air flow generally flows from positive pressure to negative pressure, in order to ensure the convection circulation operation, the air pressure at the cement rotary kiln mouth is higher than the kiln tail, and the air pressure at the flue gas circulation pipe mouth is higher than the pipe tail. In addition, in order to prevent the entry of external gas and affect the cement calcining environment, the air pressure of the cement calcining environment needs to be slightly higher than the atmospheric pressure, that is, a slightly positive pressure state.

The embodiment of the present invention uses relevant air pressure parameters of the cement calcining environment to comprehensively determine whether the cement calcining environment is in a micro-positive pressure convection circulation state based on the head and tail air pressure difference at each set time point within a set time period of the cement rotary kiln and the flue gas circulation duct, and the average air pressure at each set time point within a set time period of the cement calcining environment. This not only ensures that the cement calcining environment is in a micro-positive pressure state, but also effectively understands the airflow direction of the cement rotary kiln and the flue gas circulation duct, thereby ensuring the scientificity and accuracy of the determination result, and laying a foundation for the subsequent calcination benefit evaluation of the cement calcining environment.

The cement calcination benefit evaluation module is used to collect relevant calcination parameters of the cement calcination environment and evaluate the calcination benefit coefficient of the cement calcination environment. If it is greater than or equal to the preset reasonable calcination benefit coefficient, the cement calcination environment normal feedback module is executed, otherwise the cement calcination environment adjustment module is executed.

The relevant calcination parameters include coal consumption, electricity consumption, cement clinker output and cement clinker production area image within a set time period.

It should be noted that the coal consumption, electricity consumption, cement clinker output and cement clinker production area image within the set time period of the above-mentioned cement calcination environment are obtained from the uploaded data received by the cement calcination online energy consumption monitoring system. Specifically, the monitoring of coal consumption usually uses the flow meter or weighing sensor in the coal powder supply system, the monitoring of electricity consumption is mainly measured by the power meter, the monitoring of cement clinker output can be measured by the material flow meter or weighing sensor, and the cement clinker production area image is obtained by the high-speed camera arranged in the cement clinker production area. In addition, the image of the cement clinker production area within the set time period represents the image of the cement clinker production area corresponding to the maximum time point within the set time period.

Specifically, the evaluation of the calcination efficiency coefficient of the cement calcination environment includes: extracting the coal consumption _mcoal , electricity consumption _melectricity and cement clinker output within a set time period from the relevant calcination parameters of the cement calcination environment By formula The economic energy consumption coefficient of the cement calcining environment within the set time period is obtained, wherein k ₁ and k ₂ are respectively the reasonable thresholds of the coal consumption rate and the electricity consumption rate of the preset cement calcining environment under the state of micro-positive pressure convection circulation.

Extract the cement clinker production area image within the set time period in the relevant calcination parameters of the cement calcination environment, identify and segment the contour area of each cement clinker in the image, mark it as the surface image of each cement clinker, analyze the basic quality evaluation coefficient δ _j of each cement clinker, where j is the number of each cement clinker, j=1,2,...,n, calculate the calcination quality coefficient β ₂ within the set time period of the cement calcination environment, Where δ ₀ is the preset reasonable threshold value of the cement clinker basic quality assessment coefficient, e is a natural constant, and n is the amount of cement clinker.

By formula The calcination efficiency coefficient of cement calcination environment is obtained, where/> They are respectively the corresponding weight proportions of the economic energy consumption coefficient and the calcination quality coefficient within the preset cement calcination environment setting time period.

The embodiment of the present invention comprehensively evaluates the calcination benefit coefficient of the cement calcination environment from two aspects: the economic energy consumption coefficient and the calcination quality coefficient within a set time period of the cement calcination environment, and reasonably examines the optimization effect of the coal consumption, electricity consumption and the actual calcination quality of cement clinker under the current micro-positive pressure convection circulation state, so as to provide real-time data support and decision-making basis for the subsequent adjustment of cement calcination environment parameters.

Specifically, the analysis of the basic quality evaluation coefficient of each cement clinker includes: preprocessing and binarizing the surface images of each cement clinker to obtain the grayscale difference value x _jq between each pixel in the surface image of each cement clinker and its horizontally adjacent pixel, where q is the number of each pixel in the surface image of the cement clinker, q=1, 2, ..., p, and calculating the basic flatness h _j of each cement clinker, Where _x0 is the preset reasonable grayscale difference threshold between horizontally adjacent pixels.

The surface images of each cement clinker are further converted into RGB color space to obtain the color grayscale value g _jq of each pixel in the surface image of each cement clinker. Combined with the standard color grayscale value g ₀ of the specific cement clinker output stored in the cloud database, the basic color standardization degree s _j of each cement clinker is calculated. Where Δg is the preset color grayscale reasonable deviation threshold, and p is the number of pixels in the cement clinker surface image.

By identifying the crack features in the surface image of each cement clinker within the set time period of cement calcination, the length l _jr of each crack on the surface of each cement clinker is obtained, where r is the number of each crack on the surface of the cement clinker, r = 1, 2, ..., w, and the basic defect degree index f _j of each cement clinker is calculated.

Then by the formula The basic quality assessment coefficient of each cement clinker is obtained.

The embodiment of the present invention sets the image of the cement clinker production area within a time period, and reasonably analyzes the basic flatness, basic color compliance and basic defect degree index of the cement clinker from the grayscale characteristics, color characteristics and image crack characteristics of the pixels, which helps to comprehensively and accurately evaluate the calcination quality of the cement clinker, while effectively improving the evaluation efficiency of the calcination quality of the cement clinker.

The cement calcining environment adjustment module is used to collect the in-kiln monitoring parameters of the cement calcining environment, analyze the adjustment requirements of the air flow rate and air flow velocity in the cement rotary kiln and their corresponding adjustment parameters, and perform corresponding adjustment processing accordingly.

The monitoring parameters in the kiln include the preset air flow per unit time, the preset flue gas flow per unit time and the preset air flow velocity at the kiln mouth of the cement rotary kiln, the temperature value at each set time point in the set time period in each area of the cement rotary kiln, the material flow rate and the oxygen content.

It should be noted that the preset air flow rate per unit time, the preset flue gas flow rate per unit time and the preset air flow rate at the kiln mouth of the above-mentioned cement rotary kiln are set in advance by the cement calcination staff before cement calcination. They can be obtained by installing high-temperature resistant flow sensors and high-temperature resistant flow rate sensors at the kiln mouth, and can also be extracted at the cement calcination control center.

The various areas in the cement rotary kiln include a preheating area, a calcining area, and a cooling area. By arranging high-temperature resistant temperature sensors, material flow rate sensors, and oxygen sensors in various areas of the cement rotary kiln, the temperature values, material flow rates, and oxygen content at each set time point in a set time period in each area of the cement rotary kiln can be obtained.

Specifically, the analysis of the adjustment demand of the airflow flow in the cement rotary kiln includes: according to the temperature value t _ib and the oxygen content u _ib at each set time point in the set time period of each area in the cement rotary kiln in the kiln monitoring parameters of the cement calcining environment, wherein b is the number of each area in the cement rotary kiln, b=1, 2, ..., d, combined with the reasonable calcination temperature value t ₀ and the reasonable calcination oxygen content u ₀ of each area in the cement rotary kiln stored in the cloud database, calculate the airflow flow qualification ψ in the cement rotary kiln, Where a is the number of set time points in the set time period.

The upper limit value ψ _max and the lower limit value ψ _min of the qualified range of the airflow flow in the cement rotary kiln stored in the cloud database are extracted. If ψ _min ≤ ψ ≤ ψ _max , it means that there is no need to adjust the airflow flow in the cement rotary kiln. Otherwise, it means that there is a need to adjust the airflow flow in the cement rotary kiln.

It should be noted that the air flow rate in the cement rotary kiln includes flue gas flow rate and air flow rate. Flue gas focuses on heat supply, and air focuses on oxygen supply. The oxygen supply condition has more influence on the efficiency of cement calcination. If the oxygen content in the air flow rate is too low, it will lead to incomplete combustion or unstable flame, which will cause the temperature of each area in the cement rotary kiln to be lower than the reasonable value. If the oxygen content in the air flow rate is too high, it will lead to excessive combustion, which will cause the temperature of each area in the cement rotary kiln to be higher than the reasonable value. Under the condition that the atmospheric pressure remains unchanged in the limited cement calcination environment, the mixed air flow rate at the kiln mouth of the cement rotary kiln is kept unchanged, and the circulating air input ratio at the kiln mouth of the cement rotary kiln is adjusted to improve the adjustment of the oxygen content in the calcination environment of the cement rotary kiln.

Although during the operation of the cement rotary kiln, the adjustment of the air flow and flue gas flow at the kiln mouth will affect the micro-positive pressure state inside it, increasing the air flow at the kiln head will increase the oxygen content in the kiln, thereby promoting the combustion reaction, which may cause the temperature and pressure in the kiln to rise. On the contrary, reducing the flue gas flow in the flue gas recovery pipeline may reduce the gas emissions in the kiln, which may cause the pressure in the kiln to drop. However, when adjusting the circulating air input ratio at the kiln mouth of the cement rotary kiln, the air flow and flue gas flow at the kiln mouth will be dynamically adjusted. The effects of these two operations offset each other as much as possible, so that the micro-positive pressure state in the cement rotary kiln does not change much. Therefore, the present invention stipulates that the micro-positive pressure state of the cement calcining environment does not change when the air flow rate in the cement rotary kiln is adjusted.

Specifically, the adjustment parameters of the air flow rate in the cement rotary kiln are analyzed, including: extracting the preset air flow rate per unit time _c1 and the preset flue gas flow rate per unit time _c2 of the cement rotary kiln mouth from the kiln monitoring parameters of the cement calcining environment, accumulating them as the mixed air flow rate per unit time of the cement rotary kiln mouth, and calculating them by the formula The circulating air input ratio per unit time at the cement rotary kiln mouth is obtained.

If ψ＞ψ _max , then according to the formula The circulating air input increase ratio per unit time of the cement rotary kiln mouth is obtained, π is 180°, and its product with the mixed airflow flow per unit time of the cement rotary kiln mouth is used as the increased flue gas recovery flow per unit time of the flue gas circulation pipeline mouth and the reduced air input flow per unit time of the cement rotary kiln mouth.

If ψ＜ψ _min , then according to the formula The circulating air reduction ratio per unit time of the cement rotary kiln mouth is obtained, and its product with the mixed airflow flow per unit time of the cement rotary kiln mouth is used as the flue gas recovery reduction flow per unit time of the flue gas circulation pipeline mouth and the air input increase flow per unit time of the cement rotary kiln mouth.

It should be noted that the above-mentioned flue gas flow adjustment depends on the opening and closing of the airflow regulating valve at the pipe outlet of the flue gas recovery pipeline, and the air flow adjustment depends on the opening and closing of the airflow regulating valve at the kiln outlet of the cement rotary kiln. The opening and closing degree of the airflow regulating valve can be changed according to the ratio of the adjusted flow to the original flow.

The embodiment of the present invention effectively analyzes the adjustment requirements and specific adjustment directions of the air flow rate from two aspects of the temperature and oxygen content in the cement rotary kiln, and dynamically adjusts the circulating air input ratio while ensuring that the mixed air flow rate at the kiln mouth of the cement rotary kiln remains unchanged, thereby ensuring that the slightly positive pressure state in the cement calcining environment remains unchanged, optimizing energy utilization efficiency while reducing energy consumption, and helping to improve product quality and output.

Specifically, the analysis of the adjustment demand of the airflow velocity in the cement rotary kiln includes: extracting the reasonable calcination temperature difference Δt and the reasonable material flow rate v ₀ of adjacent areas in the cement rotary kiln stored in the cloud database according to the temperature value t _ib and the material flow rate v _ib at each set time point in the set time period in each area in the cement rotary kiln in the kiln monitoring parameters of the cement calcination environment, and calculating the airflow velocity qualification ζ in the cement rotary kiln, Wherein _ti(b-1) is the temperature value at the i-th set time point within the set time period of the b-1-th area in the cement rotary kiln.

The upper limit value ζ _max and the lower limit value ζ _min of the qualified range of the air flow velocity in the cement rotary kiln stored in the cloud database are extracted. If ζ _mni ≤ζ ≤ζ _max , it means that there is no need to adjust the air flow velocity in the cement rotary kiln. Otherwise, it means that there is a need to adjust the air flow velocity in the cement rotary kiln.

Specifically, the adjustment parameters of the air flow velocity in the cement rotary kiln are analyzed, including: extracting the preset air flow velocity τ at the kiln mouth of the cement rotary kiln from the kiln monitoring parameters of the cement calcining environment, and obtaining the average air pressure of the cement calcining environment at the current time point. _when .

It should be noted that the calculation method of the average air pressure at the current time point of the cement calcining environment is consistent with the calculation method of the average air pressure at each set time point within the set time period of the cement calcining environment.

If ζ＞ζ _max , the pressure change value of cement calcination environment corresponding to the unit air flow rate stored in the cloud database By formula/> The limited downward adjustment flow rate of the air flow velocity in the cement rotary kiln is obtained, and then the _downward adjustment flow rate τ of the air flow velocity in the cement rotary kiln is calculated.

If ζ＜ζ _min , then according to the formula The limited upward adjustment flow rate of the air flow rate in the cement rotary kiln is obtained, and then the upward adjustment flow rate τ of the air flow rate in the cement rotary kiln _is calculated, />

It should be noted that the adjustment of the air flow velocity will change the slightly positive pressure state in the cement calcining environment, that is, the air pressure in the cement calcining environment will decrease with the decrease of the air flow velocity, and increase with the increase of the air flow velocity. Therefore, it is necessary to limit the upward and downward flow rates of the air flow velocity in the cement rotary kiln in advance to prevent external gas from entering the cement calcining environment.

It should also be noted that the air flow velocity in the cement rotary kiln can be adjusted by the speed gear of the fan arranged at the kiln mouth.

The embodiment of the present invention reasonably considers the adjustment requirements and specific adjustment direction of the air flow velocity from two aspects of the temperature difference and the material flow velocity in the cement rotary kiln, and effectively adjusts the air flow velocity while maintaining a slightly positive pressure state in the cement calcining environment within the allowable fluctuation range of the air pressure in the cement calcining environment, which helps to maintain the stability of the calcining environment, thereby reducing production costs and improving the quality of cement calcining.

The cement calcining environment abnormal feedback module is used to provide abnormal feedback of the cement calcining environment, indicating that the cement calcining environment is not in a micro-positive pressure convection circulation state and the cement calcining quality is not guaranteed.

The normal feedback module for cement calcining environment is used for providing normal feedback for cement calcining environment, prompting that the current cement calcining environment parameters can be maintained, thereby effectively ensuring the quality of cement calcining.

The cloud database is used to store the qualified range of air flow velocity and air flow rate in the cement rotary kiln, store the standard color grayscale value of specific cement clinker output, store the reasonable calcination temperature value, reasonable calcination oxygen content and reasonable material flow rate of each area in the cement rotary kiln, store the reasonable calcination temperature difference between adjacent areas in the cement rotary kiln, and store the pressure change value of the cement calcination environment corresponding to the unit air flow velocity.

It should be noted that the standard color grayscale value of the above-mentioned specific cement clinker output refers to the specific color corresponding to the output under the specific component ratio of the cement clinker. Therefore, the standard color of the cement clinker output of the present invention can be set in advance by the cement calcination staff according to the component ratio.

The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the present invention, they should all fall within the protection scope of the present invention.

Claims (9)

1. A cement calcination convection circulation ventilation monitoring and management system based on the Internet of Things, characterized in that the system includes: The convection circulation state analysis module is used to collect relevant air pressure parameters of the cement calcining environment and determine whether the cement calcining environment is in a slightly positive pressure convection circulation state. If it is determined that the cement calcining environment is in a slightly positive pressure convection circulation state, the cement calcining benefit evaluation module is executed, otherwise the cement calcining environment abnormal feedback module is executed; The cement calcination benefit evaluation module is used to collect relevant calcination parameters of the cement calcination environment and evaluate the calcination benefit coefficient of the cement calcination environment. If it is greater than or equal to the preset reasonable calcination benefit coefficient, the cement calcination environment normal feedback module is executed, otherwise the cement calcination environment adjustment module is executed; The cement calcining environment adjustment module is used to collect the monitoring parameters of the cement calcining environment in the kiln, analyze the adjustment requirements of the air flow rate and air flow velocity in the cement rotary kiln and their corresponding adjustment parameters, and make corresponding adjustments accordingly; Cement calcining environment abnormality feedback module, used for cement calcining environment abnormality feedback; Cement calcining environment normal feedback module, used for cement calcining environment normal feedback; The cloud database is used to store the qualified range of air flow velocity and air flow rate in the cement rotary kiln, store the standard color grayscale value of specific cement clinker output, store the reasonable calcination temperature value, reasonable calcination oxygen content and reasonable material flow rate of each area in the cement rotary kiln, store the reasonable calcination temperature difference between adjacent areas in the cement rotary kiln, and store the pressure change value of the cement calcination environment corresponding to the unit air flow velocity. 2. According to the Internet of Things-based cement calcination convection circulation exhaust monitoring and management system of claim 1, it is characterized in that: the relevant air pressure parameters include the kiln mouth air pressure at each set time point within the set time period of the cement rotary kiln and kiln tail gas pressure/> The gas pressure at the pipe outlet at each set time point within the set time period of the flue gas circulation pipe/> and tail gas pressure Where i is the number of each set time point in the set time period, i = 1, 2, ..., a; The relevant calcination parameters include coal consumption, electricity consumption, cement clinker production and cement clinker production area image within a set time period; The monitoring parameters in the kiln include the preset air flow per unit time, the preset flue gas flow per unit time and the preset air flow velocity at the kiln mouth of the cement rotary kiln, the temperature value at each set time point in the set time period in each area of the cement rotary kiln, the material flow rate and the oxygen content. 3. According to the Internet of Things-based cement calcination convection circulation exhaust monitoring and management system of claim 2, it is characterized in that: the determination of whether the cement calcination environment is in a slightly positive pressure convection circulation state comprises: according to the relevant air pressure parameters of the cement calcination environment, respectively calculating the head and tail air pressure differences of the cement rotary kiln and the flue gas circulation pipeline at each set time point within the set time period, recorded as Calculate the average air pressure at each set time point within the set time period of the cement calcination environment When satisfied If the condition is met, it is determined that the cement calcining environment is in a state of slightly positive pressure convection circulation, otherwise it is determined that the cement calcining environment is not in a state of slightly positive pressure convection circulation, wherein _y0 is the preset atmospheric standard pressure, y′ and y″ are respectively the minimum allowable deviation value and the maximum allowable deviation value between the atmospheric pressure of the cement calcining environment and the atmospheric standard pressure under the preset state of slightly positive pressure convection circulation. 4. According to the Internet of Things-based cement calcination convection circulation ventilation monitoring and management system of claim 2, it is characterized in that: the calcination efficiency coefficient of the cement calcination environment is evaluated, including: extracting the coal consumption _mcoal , electricity consumption _melectricity and cement clinker output in the set time period from the relevant calcination parameters of the cement calcination environment By formula The economic energy consumption coefficient of the cement calcining environment within a set time period is obtained, wherein k ₁ and k ₂ are respectively the reasonable thresholds of the coal consumption rate and the electricity consumption rate of the preset cement calcining environment under the state of micro-positive pressure convection circulation; Extract the cement clinker production area image within the set time period in the relevant calcination parameters of the cement calcination environment, identify and segment the contour area of each cement clinker in the image, mark it as the surface image of each cement clinker, analyze the basic quality evaluation coefficient δ _j of each cement clinker, where j is the number of each cement clinker, j=1,2,...,n, calculate the calcination quality coefficient β ₂ within the set time period of the cement calcination environment, Where δ ₀ is the preset reasonable threshold value of cement clinker basic quality assessment coefficient, e is a natural constant, and n is the amount of cement clinker; By formula The calcination efficiency coefficient of cement calcination environment is obtained, where/> They are respectively the corresponding weight proportions of the economic energy consumption coefficient and the calcination quality coefficient within the preset time period for the cement calcination environment. 5. A monitoring and management system for cement calcination convection circulation ventilation based on the Internet of Things according to claim 4, characterized in that: the analysis of the basic quality evaluation coefficient of each cement clinker comprises: obtaining the grayscale difference value x _jq between each pixel in the surface image of each cement clinker and its horizontally adjacent pixel by preprocessing and binarizing the surface image of each cement clinker, wherein q is the number of each pixel in the surface image of the cement clinker, q=1, 2, ..., p, calculating the basic flatness h _j of each cement clinker, Where x ₀ is the preset reasonable grayscale difference threshold between horizontally adjacent pixels; The surface images of each cement clinker are further converted into RGB color space to obtain the color grayscale value g _jq of each pixel in the surface image of each cement clinker. Combined with the standard color grayscale value g ₀ of the specific cement clinker output stored in the cloud database, the basic color standardization degree s _j of each cement clinker is calculated. Where Δg is the preset color grayscale reasonable deviation threshold, and p is the number of pixels in the cement clinker surface image; By identifying the crack features in the surface image of each cement clinker within the set time period of cement calcination, the length l _jr of each crack on the surface of each cement clinker is obtained, where r is the number of each crack on the surface of the cement clinker, r = 1, 2, ..., w, and the basic defect degree index f _j of each cement clinker is calculated. Then by the formula The basic quality assessment coefficient of each cement clinker is obtained. 6. A cement calcination convection circulation exhaust monitoring and management system based on the Internet of Things according to claim 3, characterized in that: the analysis of the adjustment demand of the airflow flow in the cement rotary kiln includes: according to the temperature value t _ib and oxygen content u _ib at each set time point in the set time period of each area in the cement rotary kiln in the kiln monitoring parameters of the cement calcination environment, wherein b is the number of each area in the cement rotary kiln, b=1,2,...,d, combined with the reasonable calcination temperature value t ₀ and the reasonable calcination oxygen content u ₀ of each area in the cement rotary kiln stored in the cloud database, calculate the airflow flow qualification ψ in the cement rotary kiln, Where a is the number of set time points within the set time period; The upper limit value ψ _max and the lower limit value ψ _min of the qualified range of the airflow flow in the cement rotary kiln stored in the cloud database are extracted. If ψ _min ≤ ψ ≤ ψ _max , it means that there is no need to adjust the airflow flow in the cement rotary kiln. Otherwise, it means that there is a need to adjust the airflow flow in the cement rotary kiln. 7. A monitoring and management system for cement calcination convection circulation ventilation based on the Internet of Things according to claim 6, characterized in that: the adjustment parameters of the airflow flow rate in the cement rotary kiln are analyzed, including: extracting the preset air flow rate per unit time _c1 and the preset smoke flow rate per unit time _c2 of the cement rotary kiln mouth from the kiln monitoring parameters of the cement calcination environment, accumulating them as the mixed airflow flow rate per unit time of the cement rotary kiln mouth, and calculating the mixed airflow flow rate per unit time by the formula Obtain the circulating air input ratio per unit time at the cement rotary kiln mouth; If ψ＞ψ _max , then according to the formula The circulating air input increase ratio per unit time of the cement rotary kiln mouth is obtained, π is 180°, and the product of it and the mixed air flow rate per unit time of the cement rotary kiln mouth is used as the increased flow rate of flue gas recovery per unit time of the flue gas circulation pipe mouth and the reduced flow rate of air input per unit time of the cement rotary kiln mouth; If ψ＜ψ _min , then according to the formula The circulating air reduction ratio per unit time of the cement rotary kiln mouth is obtained, and its product with the mixed airflow flow per unit time of the cement rotary kiln mouth is used as the flue gas recovery reduction flow per unit time of the flue gas circulation pipeline mouth and the air input increase flow per unit time of the cement rotary kiln mouth. 8. A cement calcination convection circulation exhaust monitoring and management system based on the Internet of Things according to claim 6, characterized in that: the analysis of the adjustment demand of the airflow velocity in the cement rotary kiln includes: according to the temperature value _tib and the material flow rate _vib of each area in the cement rotary kiln at each set time point within the set time period in the kiln monitoring parameters of the cement calcination environment, extracting the reasonable material flow rate _v0 of each area in the cement rotary kiln and the reasonable calcination temperature difference Δt between adjacent areas stored in the cloud database, calculating the airflow velocity qualification ζ in the cement rotary kiln, Wherein _ti(b-1) is the temperature value of the i-th set time point within the set time period of the b-1th area in the cement rotary kiln; The upper limit value ζ _max and the lower limit value ζ _min of the qualified range of the air flow velocity in the cement rotary kiln stored in the cloud database are extracted. If ζ _min ≤ζ ≤ζ _max , it means that there is no need to adjust the air flow velocity in the cement rotary kiln. Otherwise, it means that there is a need to adjust the air flow velocity in the cement rotary kiln. 9. A cement calcination convection circulation exhaust monitoring and management system based on the Internet of Things according to claim 8, characterized in that: the analysis of the adjustment parameters of the airflow velocity in the cement rotary kiln includes: extracting the preset airflow velocity τ of the cement rotary kiln mouth from the kiln monitoring parameters of the cement calcination environment, and obtaining the average air pressure of the cement calcination environment at the current time point If ζ＞ζ _max , the pressure change value of cement calcination environment corresponding to the unit air flow rate stored in the cloud database By formula/> The limited downward adjustment flow rate of the air flow velocity in the cement rotary kiln is obtained, and then the _downward adjustment flow rate τ of the air flow velocity in the cement rotary kiln is calculated. If ζ＜ζ _min , then according to the formula The limited upward adjustment flow rate of the air flow velocity in the cement rotary kiln is obtained, and then the upward adjustment flow rate τ of the air flow velocity in the cement rotary kiln _is calculated.