Coal supply system of thermal power plant

Abstract

The invention provides a coal supply system of a thermal power plant, which relates to the field of thermal power generation, and comprises a coal pile distribution module for dividing into a plurality of coal piles according to a fire coal source and a preliminary evaluation result; the coal quality detection module is used for extracting a sample for experiment and determining combustion influence parameters; the calorific value simulation module simulates the combustion process and determines the actual calorific value of the fire coal in each coal pile; the coal bunker matching module is used for matching each coal pile with superior, medium and inferior coal bunkers based on the actual heating value and conveying fire coal; the coal quantity distribution module distributes the coal supply quantity in a most economical manner based on a distribution optimization model, performs optimization distribution according to the storage quantity proportion of each coal bunker, and generates a distribution scheme; the control module is used for implementing coal supply action according to the generated distribution scheme; the invention aims to establish the calorific value simulation model to realize accurate coal bunker matching by optimizing sampling and analysis in the coal quality detection process, and adopts the coal supply quantity distribution model comprehensively considering various factors to improve the efficiency and economical efficiency of the coal supply system of the thermal power plant.

Description

Technical Field

[0001] The invention relates to the technical field of thermal power generation, and in particular to a coal supply system for a thermal power plant. Background Art

[0002] With the acceleration of industrialization, the demand for electricity continues to grow. As one of the main ways of power generation, thermal power generation occupies an important position in energy supply. The coal supply system of early thermal power plants was relatively simple, mainly transporting coal directly to boilers for combustion, and paying less attention to coal quality control and accurate distribution of coal supply. With the advancement of technology, people gradually realized the important impact of coal quality on power generation efficiency and environmental protection. Therefore, coal quality testing technology began to develop, from the initial simple physical testing to the use of advanced instruments and equipment for comprehensive chemical analysis, which can accurately measure the content of various components of coal and key parameters such as calorific value.

[0003] The current coal bunker matching method often simply divides the corresponding relationship between coal and coal bunker based on the threshold range of several key indicators. However, the combustion performance of coal is affected by a variety of factors. This single-dimensional matching method causes some coal to not be allocated to the most suitable coal bunker, thus affecting the combustion efficiency and power generation cost. At the same time, most existing technologies only focus on meeting the heat demand of boilers, without fully considering factors such as the cost of coal, the storage capacity of coal bunkers, and the difference in coal quality in different coal bunkers. This results in a high power generation cost, or a backlog of coal in some coal bunkers while other coal bunkers are emptied prematurely, affecting the stability and economy of the coal supply system.

[0004] Therefore, there is an urgent need in the art for a coal supply system for a thermal power plant to solve the above problems. Summary of the invention

[0005] The present invention provides a coal supply system for a thermal power plant, which aims to improve the efficiency and economy of the coal supply system of a thermal power plant by optimizing the sampling and analysis methods of the coal quality detection process, establishing a calorific value simulation model to achieve more accurate coal bunker matching, and adopting a coal supply allocation model that comprehensively considers multiple factors.

[0006] The present invention provides a coal supply system for a thermal power plant, comprising:

[0007] A coal pile allocation module, which is used to divide the coal into several coal piles according to the coal source and the preliminary evaluation result;

[0008] Coal quality detection module, which is used to extract samples from each coal pile for experiments to determine the combustion influencing parameters of the coal in different coal piles;

[0009] A calorific value simulation module, which is connected to the coal quality detection module and is used to simulate the combustion process according to the combustion influencing parameters to determine the actual calorific value of the coal in each coal pile;

[0010] A coal bunker matching module, which is connected to the calorific value simulation module, and is used to match each coal pile with three types of coal bunkers, namely, good, medium and poor, according to the actual calorific value of the coal in each coal pile, and transport the coal to the coal bunker based on the matching result;

[0011] The coal quantity allocation module is used to obtain the current boiler heat demand and the storage capacity of the three types of coal bunkers, and allocate the coal supply of the three types of coal bunkers in the most economical way based on the preset allocation optimization model. At the same time, it optimizes the allocation according to the storage capacity ratio of each coal bunker, determines the ideal coal supply of the three types of coal bunkers, and generates an allocation plan;

[0012] A control module is connected to the coal quantity allocation module and is used to implement the coal supply action according to the generated allocation plan.

[0013] According to a coal supply system for a thermal power plant provided by the present invention, the coal pile distribution module comprises:

[0014] The source identification unit is used to identify the source information of the coal, including different suppliers and mining areas. Specifically, it determines the specific source of each batch of coal by reading and analyzing the transportation documents and labels of the coal entering the factory, and establishes a source database for subsequent tracing and statistical analysis;

[0015] A preliminary evaluation unit, which is used to make a preliminary judgment on the quality of the coal by manually observing the appearance characteristics of the coal, namely, color, particle size, and uniformity, and to generate and record preliminary evaluation results;

[0016] The coal pile division unit is connected to the source identification unit and the preliminary evaluation unit, and is used to divide the incoming coal into several coal piles according to the source information of the coal and the preliminary evaluation result, and to mark each coal pile with a number.

[0017] According to a coal supply system for a thermal power plant provided by the present invention, the coal quality detection module comprises:

[0018] A sampling unit, which is used to extract representative coal samples from each coal pile by an automatic sampler;

[0019] An experimental analysis unit connected to the sampling unit is used to perform experimental analysis on the collected coal samples to determine the combustion influencing parameters of the coal in each coal pile; the combustion influencing parameters include theoretical calorific value, volatile matter content, moisture content, ash content, fixed carbon content and sulfur content data;

[0020] A data recording unit is connected to the experimental analysis unit and is used to establish a combustion parameter database, and to record and store the combustion influencing parameters of the coal currently burning in each coal pile obtained by the experimental analysis unit.

[0021] According to a coal supply system for a thermal power plant provided by the present invention, the calorific value simulation module comprises:

[0022] The model building unit is used to pre-build a heat generation simulation model, wherein the heat generation simulation model is:

[0023] Q act =Q the *(1+F vol +F fix -F moil -F ash -F sul )

[0024] Among them, Q act is the actual heat generated, Q the is the theoretical calorific value, F vol is the volatile content, F fix is the fixed carbon fraction, F moil is the moisture value, F ash is the ash value, F sul is the sulfur content;

[0025] Volatile value Where V is the volatile content data, Q ecvv The equivalent calorific value contributed by the volatile matter during the combustion process is obtained through statistical analysis of experimental data, and the average equivalent calorific value of the volatile matter under different combustion conditions is used as a constant value;

[0026] Fixed Carbon Score Where FC is the fixed carbon content data, Q ecvf The equivalent calorific value contributed by the fixed carbon in the combustion process is also obtained through experimental data statistics, and the average equivalent calorific value of the fixed carbon under different combustion conditions is used as a constant value;

[0027] Moisture value Where M is the moisture content data, Q is the heat absorbed by the moisture during the heating process to the combustion temperature, ham =M*C*(T f -T0), C is the specific heat capacity, T f is the combustion temperature, T0 is the initial temperature;

[0028] Ash value Where A is the ash content data, Q haa It is the heat absorbed by the ash during the heating process, which is calculated based on the specific heat capacity of the ash, the ash content, and the difference between the combustion temperature and the initial temperature; Qaloss The heat carried away by the residual ash is obtained by statistically analyzing the residual ash ratio and the average heat carried away by the residual ash during the cooling process as a constant value;

[0029] Sulfur content Where S is the sulfur content data, Q has is the amount of heat absorbed by sulfur during the heating process, which is calculated based on the specific heat capacity of sulfur, sulfur content, and the difference between the combustion temperature and the initial temperature; Q sloss The heat carried away by the sulfur combustion products is obtained through experimental data statistics, and the average heat loss of the sulfur combustion products is used as a constant;

[0030] The calorific value calculation unit is connected to the data recording unit and the model building unit, and is used to input the combustion influencing parameters into the calorific value simulation model, calculate and output the actual calorific value Q of the coal in each coal pile. act i.

[0031] According to a coal supply system for a thermal power plant provided by the present invention, the coal bunker matching module comprises:

[0032] A matching decision unit is connected to the calorific value calculation unit and is used to pre-establish a high calorific value threshold range, a medium calorific value threshold range, and a low calorific value threshold range corresponding to the three types of coal bunkers: excellent, medium, and inferior; compare the actual calorific value with the threshold range, determine the coal bunker to which the coal belongs, and generate matching results for each coal pile and the three types of coal bunkers: excellent, medium, and inferior;

[0033] A transport control unit is connected to the matching decision unit and is used to control the transport equipment to transport the coal in each coal pile to the corresponding coal bunker according to the matching result.

[0034] According to a coal supply system for a thermal power plant provided by the present invention, the coal quantity allocation module comprises:

[0035] A factor acquisition unit, which is used to obtain the heat demand data of the current boiler, the storage capacity information of the three types of coal bunkers, the unit coal supply cost of the coal burned in the three types of coal bunkers, and the median of the calorific value threshold range corresponding to the three types of coal bunkers;

[0036] an optimization allocation unit connected to the factor acquisition unit, which allocates the ideal coal supply amount of each coal bunker to the boiler based on the allocation optimization model and generates an allocation plan;

[0037] The allocation optimization model is:

[0038] Objective function: minimizeZ = C A *m A +C B *m B +C C*m C

[0039] Heat demand constraint: Qde m =m A *Q A +m B *Q B +m C *Q C

[0040] Non-negative constraint condition for coal supply: m A ≥0,m B ≥0,m C ≥0

[0041] m A =λ*P A *(S tota1 -m A -m B -m C )

[0042] Proportional constraint: m B =λ*P B *(S total -m A -m B -m C )

[0043] m C =λ*P C *(S total -m A -m B -m C )

[0044] Among them, minimizeZ represents minimizing cost, C A , C B , C C The unit coal supply costs of three types of coal bunkers, namely, high-quality, medium-quality and low-quality, m A 、m B 、m C are the ideal coal supply of the three types of coal bunkers that need to be determined; Q dem is the current boiler heat demand data, Q A , Q B , Q C are the median values ​​of the calorific value threshold ranges corresponding to the three types of coal bunkers; S tota1 is the sum of the storage capacity of the three types of coal bunkers, that is, S total =S A +S B +S C , where S A , S B , SC are the storage capacity of the three types of coal bunkers at present; P A , P B , P C is the scale parameter, that is λ is the proportional adjustment coefficient, which is used to achieve the proportional balance of the storage capacity of the three types of coal bunkers;

[0045] Determine the ideal coal supply m of three types of coal bunkers by linear programming solution method A 、m B 、m C , generate the current allocation plan.

[0046] According to a coal supply system for a thermal power plant provided by the present invention, the control module comprises:

[0047] An instruction generating unit, connected to the optimization allocation unit, generates a corresponding instruction signal based on the current allocation scheme;

[0048] The equipment control unit is connected to the instruction generating unit and is used to receive the instruction signal, control the start, stop and speed adjustment operation of the conveying equipment according to the instruction signal, and control the discharge valve and baffle equipment of the coal bunker to ensure the accurate distribution and flow control of the coal.

[0049] According to a coal supply system for a thermal power plant provided by the present invention, the instruction generation unit selects a PID controller, and the generated instruction signal includes the coal supply amount of each coal bunker and randomly generated coal supply sequence information.

[0050] Compared with the prior art, the beneficial effects of this application are:

[0051] This system comprehensively considers the impact of multiple components in coal, such as volatile matter, fixed carbon, moisture, ash, sulfur, etc. on calorific value, and can more accurately calculate the actual calorific value of the coal in each coal pile; according to the calorific value data and the more reasonable calorific value threshold ranges corresponding to the three types of coal bunkers, which are pre-established, each coal pile is matched with the coal bunker to ensure that the coal is allocated to the most suitable bunker, thereby improving combustion efficiency and reducing power generation costs;

[0052] When allocating coal supply, this system not only considers the heat demand of the boiler, but also fully considers factors such as the unit coal supply cost of each of the three types of coal bunkers, the storage capacity of the three types of coal bunkers, and the storage ratio of each coal bunker. By calculating based on the preset allocation optimization model, the coal supply of the three coal bunkers can be allocated in the most economical way. At the same time, the system optimizes the allocation according to the storage ratio of each coal bunker, avoiding the situation where some coal bunkers are piled up while other coal bunkers are emptied prematurely, thereby improving the stability and economy of the coal supply system.

[0053] This system takes cost factors into comprehensive consideration during the coal supply allocation process, gives priority to the use of coal with lower unit coal supply cost, and reasonably adjusts the coal supply ratio of each coal bunker, which can effectively reduce the cost of power generation and improve the economic benefits of thermal power plants.

[0054] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0055] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0057] Figure 1 The present invention is a schematic structural diagram of a coal supply system for a thermal power plant provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0058] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0059] Embodiment 1:

[0060] The embodiment of the present invention provides a coal supply system for a thermal power plant. Figure 1 ,include:

[0061] A coal pile allocation module, which is used to divide the coal into several coal piles according to the coal source and the preliminary evaluation result;

[0062] Coal quality detection module, which is used to extract samples from each coal pile for experiments to determine the combustion influencing parameters of the coal in different coal piles;

[0063] A calorific value simulation module, which is connected to the coal quality detection module and is used to simulate the combustion process according to the combustion influencing parameters and determine the actual calorific value of the coal in each coal pile;

[0064] A coal bunker matching module is connected to the calorific value simulation module and is used to match each coal pile with three types of coal bunkers, namely, good, medium and poor, according to the actual calorific value of the coal in each coal pile, and to transport the coal to the coal bunker based on the matching results;

[0065] The coal quantity allocation module is used to obtain the current boiler heat demand and the storage capacity of the three types of coal bunkers, and allocate the coal supply of the three types of coal bunkers in the most economical way based on the preset allocation optimization model. At the same time, it optimizes the allocation according to the storage capacity ratio of each coal bunker, determines the ideal coal supply of the three types of coal bunkers, and generates an allocation plan;

[0066] The control module is connected to the coal quantity allocation module and is used to implement the coal supply action according to the generated allocation plan.

[0067] The principle of the above embodiment is: classify the coal according to its source and preliminary evaluation results to form different coal piles; extract samples from each coal pile for testing and analysis to obtain key parameters about combustion performance, such as ash content, volatile matter ratio, etc.; use the previously obtained data to simulate the performance under actual combustion conditions and calculate the actual available calorific value of each type of coal; allocate the coal to corresponding storage areas (excellent, medium and inferior categories) based on its calorific value information to ensure that high-value fuel is fully utilized; consider the current boiler demand and existing inventory status, and use a mathematical model to determine how much coal to take from each type of coal bin to achieve the lowest cost and the best solution to meet production needs; execute the finalized coal supply plan, including starting related equipment to complete material handling and other tasks.

[0068] The beneficial effects of the above embodiments are: through refined management of coal, the ratio of high-quality coal to ordinary or low-quality coal can be arranged more reasonably, ensuring the effective use of energy; the most economical ratio is selected through the optimization algorithm to reduce unnecessary waste, indirectly reducing the overall operating expenses of the enterprise; when market demand changes or raw material supply fluctuates, the system can quickly adjust the strategy to maintain the continuity and stability of production; a more efficient combustion process means reducing the emission of harmful substances, which is in line with the development trend of energy conservation and emission reduction; the entire process is highly integrated and intelligent, reducing the need for manual intervention and the possibility of operational errors.

[0069] In order to further optimize the above embodiment, the coal pile allocation module includes:

[0070] The source identification unit is used to identify the source information of the coal, including different suppliers and mining areas. Specifically, it determines the specific source of each batch of coal by reading and analyzing the transportation documents and labels of the coal entering the factory, and establishes a source database for subsequent tracing and statistical analysis;

[0071] A preliminary evaluation unit, which is used to make a preliminary judgment on the quality of the coal by manually observing the appearance characteristics of the coal, namely, color, particle size, and uniformity, and to generate and record preliminary evaluation results;

[0072] The coal pile division unit is connected to the source identification unit and the preliminary assessment unit, and is used to divide the incoming coal into several coal piles in combination with the source information of the coal and the preliminary assessment results, and to number and mark each coal pile.

[0073] It should be noted that the source identification unit obtains data related to the source of coal by reading and analyzing the transportation documents and identification information of the coal entering the factory; these data include key information such as the supplier name and the location of the mine area; the purpose of establishing a source database is to be able to record the source of each batch of coal in detail, so that when quality problems or other situations that require traceability occur in the future, the source can be found quickly and accurately, and it is also convenient for statistical analysis, such as analyzing the quality distribution of coal from different suppliers or mines; optical character recognition (OCR) technology can be used to identify the text information on the transportation documents and extract key information such as the supplier name and mine area name; for the identification of coal, radio frequency identification (RFID) technology or barcode scanning technology can be used for reading; to establish a source database, a common relational database management system (such as MySQL, Oracle, etc.) can be used to store the extracted source information and related batch information, entry time and other data in the database;

[0074] The appearance characteristics of coal can reflect its quality to a certain extent; for example, coal with a dark and uniform color, moderate particle size and good uniformity may be of relatively good quality; by observing these appearance characteristics manually, a preliminary and qualitative judgment can be made on the quality of coal; recording the preliminary evaluation results is to provide a reference basis for the subsequent division of coal piles, so that the divided coal piles have a certain similarity in quality; special staff can be arranged to observe and evaluate the appearance of coal when it enters the factory; in order to improve the accuracy and consistency of the evaluation, detailed appearance evaluation standards and guidelines can be formulated, such as clarifying the color range, particle size range and uniformity standards corresponding to different quality grades; the preliminary evaluation results can be recorded in paper forms or electronic forms and associated with the corresponding coal pile numbers;

[0075] Combined with the coal source information determined by the source identification unit and the preliminary quality assessment results given by the preliminary assessment unit, the coal entering the factory is reasonably divided; the purpose of such division is to be able to handle coal of different quality and sources more targeted in subsequent operations such as coal quality testing, coal bunker matching and coal supply allocation; numbering and marking each coal pile is to facilitate management and identification, to ensure that each coal pile can be accurately tracked and processed; according to the source and preliminary assessment results, automated zoning equipment (such as a conveyor belt and baffle combination with an intelligent control system) can be used to divide the coal into different areas to form coal piles; or manual guidance can be used, using loaders and other equipment to move the coal to designated areas to form coal piles; in the division process, each coal pile is also numbered and marked, and metal plates or plastic plates can be used for marking, with key information such as the coal pile number, source information, preliminary assessment results, etc. indicated on the mark.

[0076] In order to further optimize the above embodiment, the coal quality detection module includes:

[0077] A sampling unit, which is used to extract representative coal samples from each coal pile by an automatic sampler;

[0078] An experimental analysis unit, which is connected to the sampling unit and is used to perform experimental analysis on the collected coal samples to determine the combustion influencing parameters of the coal in each coal pile; the combustion influencing parameters include theoretical calorific value, volatile matter content, moisture content, ash content, fixed carbon content and sulfur content data;

[0079] The data recording unit is connected to the experimental analysis unit and is used to establish a combustion parameter database, and to record and store the combustion influencing parameters of the coal currently burning in each coal pile obtained by the experimental analysis unit.

[0080] It should be noted that in order to accurately understand the quality of the coal in each coal pile, it is necessary to extract representative coal samples; the automatic sampler can sample at different positions and depths of the coal pile according to the predetermined sampling rules and methods to ensure that the collected coal samples can reflect the quality characteristics of the entire coal pile; the automatic sampler can be combined with a mechanical arm and a sampling probe; the mechanical arm can move on the surface and inside of the coal pile according to the preset program, and the sampling probe is responsible for collecting coal samples; the sampling probe can be designed to have a layered sampling function and can collect coal samples at different depths; at the same time, in order to ensure the randomness and representativeness of the sampling, multiple sampling points can be set, and the distribution of the sampling points can be reasonably planned according to the shape and size of the coal pile;

[0081] The experimental analysis unit can be equipped with a variety of advanced experimental equipment; for example, the theoretical calorific value of coal samples can be measured using an oxygen bomb calorimeter; the volatile matter content, fixed carbon content and ash content can be determined using an industrial analyzer; the sulfur content can be detected using an elemental analyzer; the moisture content can be measured using conventional methods such as the drying method; these devices can be operated in accordance with the corresponding experimental standards and operating procedures to ensure the accuracy and reliability of the measurement results;

[0082] The data recording unit can be implemented using a database management system; for example, a relational database such as MySQL or Oracle can be selected; a database table containing fields such as coal pile number, sampling time, and various combustion influencing parameters is established; after the experimental analysis unit obtains the measurement results, the data recording unit inserts these data into the database table in a predetermined format to achieve data storage and management; at the same time, a corresponding query interface can be developed to facilitate other modules to query and use these data.

[0083] In order to further optimize the above embodiment, the heat generation simulation module includes:

[0084] The model building unit is used to pre-build a heat generation simulation model, and the heat generation simulation model is:

[0085] Q act =Q the *(1+F vol +F fix -F moil -F ash -F sul )

[0086] Among them, Q act is the actual heat generated, Q the is the theoretical calorific value, F vol is the volatile content, F fix is the fixed carbon fraction, F moil is the moisture value, F ash is the ash value, F sul is the sulfur content;

[0087] Volatile value Where V is the volatile content data, Q ecvv The equivalent calorific value contributed by the volatile matter during the combustion process is obtained through statistical analysis of experimental data, and the average equivalent calorific value of the volatile matter under different combustion conditions is used as a constant value;

[0088] Fixed Carbon Score Where FC is the fixed carbon content data, Q ecvf The equivalent calorific value contributed by the fixed carbon in the combustion process is also obtained through experimental data statistics, and the average equivalent calorific value of the fixed carbon under different combustion conditions is used as a constant value;

[0089] Moisture value Where M is the moisture content data, Q is the heat absorbed by the moisture during the heating process to the combustion temperature, ham =M*C*(T f -T0), C is the specific heat capacity, T f is the combustion temperature, T0 is the initial temperature;

[0090] Ash value Where A is the ash content data, Q haa It is the heat absorbed by the ash during the heating process, which is calculated based on the specific heat capacity of the ash, the ash content, and the difference between the combustion temperature and the initial temperature; Q aloss The heat carried away by the residual ash is obtained by statistically analyzing the residual ash ratio and the average heat carried away by the residual ash during the cooling process as a constant value;

[0091] Sulfur content Where S is the sulfur content data, Q has is the amount of heat absorbed by sulfur during the heating process, which is calculated based on the specific heat capacity of sulfur, sulfur content, and the difference between the combustion temperature and the initial temperature; Q sloss The heat carried away by the sulfur combustion products is obtained through experimental data statistics, and the average heat loss of the sulfur combustion products is used as a constant;

[0092] The calorific value calculation unit is connected to the data recording unit and the model building unit, and is used to input the combustion influencing parameters into the calorific value simulation model, calculate and output the actual calorific value Q of the coal in each coal pile. act i.

[0093] It should be noted that the actual calorific value is based on the theoretical calorific value, and takes into account the comprehensive effects of volatile matter, fixed carbon, moisture, ash, sulfur and other components on the calorific value; (1+F vol +F fix -F moil -F ash -F sul ) This part indicates the correction coefficient of each component to the theoretical calorific value; when the volatile matter and fixed carbon content increase, the actual calorific value will increase; and when the moisture, ash and sulfur content increase, the actual calorific value will decrease;

[0094] The volatile matter value is determined by the volatile matter content, the equivalent calorific value contributed by the volatile matter during the combustion process, and the theoretical calorific value; the higher the volatile matter content and the greater the ratio of its equivalent calorific value to the theoretical calorific value, the higher the volatile matter value, and the more obvious the effect of increasing the actual calorific value; the fixed carbon score depends on the fixed carbon content, the equivalent calorific value contributed by the fixed carbon during the combustion process, and the theoretical calorific value; the higher the fixed carbon content and the greater the ratio of its equivalent calorific value to the theoretical calorific value, the higher the fixed carbon score, and the more obvious the effect of increasing the actual calorific value; the moisture value is determined by the moisture content, the heat absorbed by the moisture during the temperature rise to the combustion temperature, and the theoretical calorific value; the higher the moisture content and the greater the ratio of the heat absorbed by the moisture to the theoretical calorific value, the higher the fixed carbon score, and the more obvious the effect of increasing the actual calorific value. The greater the proportion to the theoretical calorific value, the higher the moisture value, and the stronger the effect of reducing the actual calorific value; the ash value is determined by the ash content, the heat absorbed by the ash during the heating process, the heat carried away by the residual ash, and the theoretical calorific value; the higher the ash content, and the greater the proportion of the heat absorbed by the ash and the residual heat carried away relative to the theoretical calorific value, the higher the ash value, and the more obvious the effect of reducing the actual calorific value; the sulfur value is determined by the sulfur content, the heat absorbed by the sulfur during the heating process, the heat carried away by the sulfur combustion products, and the theoretical calorific value; the higher the sulfur content, and the greater the proportion of the heat absorbed by the sulfur and the combustion products carried away relative to the theoretical calorific value, the higher the sulfur value, and the more significant the effect of reducing the actual calorific value.

[0095] In order to further optimize the above embodiment, the coal bunker matching module includes:

[0096] A matching decision unit is connected to the calorific value calculation unit and is used to pre-establish a high calorific value threshold range, a medium calorific value threshold range, and a low calorific value threshold range corresponding to the three types of coal bunkers: excellent, medium, and inferior; compare the actual calorific value with the threshold range, determine the coal bunker to which the coal belongs, and generate matching results for each coal pile and the three types of coal bunkers: excellent, medium, and inferior;

[0097] The transport control unit is connected to the matching decision unit and is used to control the transport equipment to transport the coal in each coal pile to the corresponding coal bunker according to the matching result.

[0098] It should be noted that for the matching decision unit, the calorific value threshold ranges corresponding to the three types of coal bunkers, namely, high-quality, medium-quality and low-quality coal bunkers can be determined by statistically analyzing the calorific value data of a large number of coal samples; for example, coal samples of different sources and qualities are collected, and their actual calorific values ​​are accurately calculated using the above-mentioned calorific value simulation module; these calorific value data are then sorted and grouped, and according to actual production needs and experience, it is determined that the high calorific value threshold range corresponds to the high-quality coal bunker (such as the actual calorific value is greater than or equal to a certain specific value), the medium calorific value threshold range corresponds to the medium coal bunker (between two specific values), and the low calorific value threshold range corresponds to the low-quality coal bunker. Inferior coal bunker (less than or equal to a certain specific value); for the transportation control unit, it can communicate with the control system of the transportation equipment (such as belt conveyor, coal feeder, etc.); after receiving the matching result from the matching decision unit, if a coal pile matches with a high-quality coal bunker, the transportation control unit sends a start instruction to the transportation equipment corresponding to the high-quality coal bunker, and sets a suitable transportation speed (which can be dynamically adjusted according to factors such as the remaining capacity of the coal bunker and the heat demand of the boiler) to transport the coal in the coal pile to the high-quality coal bunker; similar control logic is also used for medium-quality coal bunkers and inferior coal bunkers to ensure that the coal is accurately transported to the corresponding coal bunker.

[0099] In order to further optimize the above embodiment, the coal quantity allocation module includes:

[0100] A factor acquisition unit, which is used to obtain the heat demand data of the current boiler, the storage capacity information of the three types of coal bunkers, the unit coal supply cost of the coal burned in the three types of coal bunkers, and the median of the calorific value threshold range corresponding to the three types of coal bunkers;

[0101] An optimization allocation unit, which is connected to the factor acquisition unit, allocates the ideal coal supply of each coal bunker to the boiler based on the allocation optimization model and generates an allocation plan;

[0102] The allocation optimization model is:

[0103] Objective function: minimizeZ = C A *m A +C B *m B +C C *m C

[0104] Heat demand constraint: Q dem =m A *Q A +m B *Q B +m C *Q C

[0105] Non-negative constraint condition for coal supply: m A ≥0,mB ≥0,m C ≥0

[0106] m A =λ*P A *(S tota1 -m A -m B -m C )

[0107] Proportional constraint: m B =λ*P B *(S total -m A -m B -m C )

[0108] m C =λ*P C *(S total -m A -m B -m C )

[0109] Among them, minimizeZ represents minimizing cost, C A , C B , C C The unit coal supply costs of three types of coal bunkers, namely, high-quality, medium-quality and low-quality, m A 、m B 、m C are the ideal coal supply of the three types of coal bunkers that need to be determined; Q dem is the current boiler heat demand data, Q A , Q B , Q C are the median values ​​of the calorific value threshold ranges corresponding to the three types of coal bunkers; S total is the sum of the storage capacity of the three types of coal bunkers, that is, S total =S A +S B +S C , where S A , S B , S C are the storage capacity of the three types of coal bunkers at present; P A , P B , P C is the scale parameter, that is λ is the proportional adjustment coefficient, which is used to achieve the proportional balance of the storage capacity of the three types of coal bunkers;

[0110] Determine the ideal coal supply m of three types of coal bunkers by linear programming solution method A 、m B 、mC , generate the current allocation plan.

[0111] It should be noted that the coal allocation module aims to meet the heat demand of the boiler in the most economical way, while taking into account the storage capacity of the three types of coal bunkers and the cost difference of coal in each coal bunker to achieve reasonable coal supply allocation; for the proportion adjustment coefficient, the coal supply data of the thermal power plant in the past period of time can be collected, including the storage capacity changes of different coal bunkers, coal supply allocation and boiler heat demand information; analyze these data to observe how the system adjusts the coal supply to maintain balance under different storage capacity ratios, and the impact of this adjustment on power generation costs and boiler operation stability; based on the analysis results, summarize the approximate range of proportion adjustment coefficients suitable for different situations;

[0112] There is no unique method for solving linear programming, including but not limited to the simplex method, interior point method, etc. The calculation principle is an existing technical means, so it will not be elaborated in detail.

[0113] In order to further optimize the above embodiment, the control module includes:

[0114] An instruction generation unit, which is connected to the optimization allocation unit and generates a corresponding instruction signal based on the current allocation scheme;

[0115] The equipment control unit is connected to the instruction generation unit and is used to receive the instruction signal, control the start, stop and speed adjustment operation of the conveying equipment according to the instruction signal, and control the discharge valve and damper equipment of the coal bunker to ensure the accurate distribution and flow control of the coal;

[0116] The instruction generation unit selects a PID controller, and the generated instruction signal includes the coal supply quantity of each coal bin and the randomly generated coal supply sequence information.

[0117] It should be noted that the PID controller controls the system through three links: proportional (P), integral (I) and differential (D); in this embodiment, it is used to generate a suitable command signal according to the current allocation scheme;

[0118] The proportional link (P) produces a control effect in proportion to the current error (the difference between the actual value and the set value); for example, if the current coal supply in the coal bunker deviates from the set ideal coal supply, the proportional link will generate a corresponding control signal based on this deviation to adjust the coal supply in the direction of the set value;

[0119] The integral link (I) is mainly used to eliminate the steady-state error of the system; it integrates the error. As time accumulates, even if the deviation is very small, the integral link can produce a large enough control effect to make the system eventually reach a stable state without steady-state error;

[0120] The differential link (D) produces a control effect based on the rate of change of the error. When the system error changes rapidly, the differential link will generate a large control signal, enabling the system to respond quickly and avoid instability such as overshoot or oscillation.

[0121] After receiving the current allocation plan from the optimization allocation unit, the PID controller in the instruction generation unit first obtains the actual value of the current coal supply of each coal bin (which can be obtained through sensor feedback or other monitoring means) and the set ideal coal supply (from the allocation plan); then calculates the error (ideal coal supply - actual coal supply); based on the error, calculates the proportional control signal through the proportional link, calculates the integral control signal through the integral link, and calculates the differential control signal through the differential link; finally, the three control signals are weighted and summed (different weights can be set according to actual conditions) to obtain the final control signal;

[0122] This final control signal will be converted into an instruction signal containing the coal supply quantity and coal supply sequence information of each coal bunker; for example, if the final control signal indicates that the coal supply quantity of the high-quality coal bunker needs to be increased, then the coal supply quantity value of the high-quality coal bunker will be adjusted accordingly in the instruction signal; at the same time, the randomly generated coal supply sequence information will also be added to the instruction signal; a random number generation algorithm (such as the random module in Python) can be used to randomly generate the coal supply sequence;

[0123] The format of the command signal can be a specific data structure, such as a structure or class containing fields such as coal bunker number, coal supply quantity, operation type (start, stop, speed adjustment) and coal supply sequence; the command signal can be transmitted to the equipment control unit using communication technologies such as industrial Ethernet and field bus (such as Profibus, CAN bus, etc.).

[0124] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A coal supply system for a thermal power plant, characterized in that: include: A coal pile allocation module, which is used to divide the coal into several coal piles according to the coal source and the preliminary evaluation result; Coal quality detection module, which is used to extract samples from each coal pile for experiments to determine the combustion influencing parameters of the coal in different coal piles; A calorific value simulation module, which is connected to the coal quality detection module and is used to simulate the combustion process according to the combustion influencing parameters to determine the actual calorific value of the coal in each coal pile; A coal bunker matching module, which is connected to the calorific value simulation module, and is used to match each coal pile with three types of coal bunkers, namely, good, medium and poor, according to the actual calorific value of the coal in each coal pile, and transport the coal to the coal bunker based on the matching result; The coal quantity allocation module is used to obtain the current boiler heat demand and the storage capacity of the three types of coal bunkers, and allocate the coal supply of the three types of coal bunkers in the most economical way based on the preset allocation optimization model. At the same time, it optimizes the allocation according to the storage capacity ratio of each coal bunker, determines the ideal coal supply of the three types of coal bunkers, and generates an allocation plan; A control module is connected to the coal quantity allocation module and is used to implement the coal supply action according to the generated allocation plan.

2. A coal supply system for a thermal power plant according to claim 1, characterized in that: The coal pile distribution module comprises: The source identification unit is used to identify the source information of the coal, including different suppliers and mining areas. Specifically, it determines the specific source of each batch of coal by reading and analyzing the transportation documents and labels of the coal entering the factory, and establishes a source database for subsequent tracing and statistical analysis; A preliminary evaluation unit, which is used to make a preliminary judgment on the quality of the coal by manually observing the appearance characteristics of the coal, namely, color, particle size, and uniformity, and to generate and record preliminary evaluation results; The coal pile division unit is connected to the source identification unit and the preliminary evaluation unit, and is used to divide the incoming coal into several coal piles according to the source information of the coal and the preliminary evaluation result, and to mark each coal pile with a number.

3. A coal supply system for a thermal power plant according to claim 2, characterized in that: The coal quality detection module comprises: A sampling unit, which is used to extract representative coal samples from each coal pile by an automatic sampler; An experimental analysis unit connected to the sampling unit is used to perform experimental analysis on the collected coal samples to determine the combustion influencing parameters of the coal in each coal pile; the combustion influencing parameters include theoretical calorific value, volatile matter content, moisture content, ash content, fixed carbon content and sulfur content data; A data recording unit is connected to the experimental analysis unit and is used to establish a combustion parameter database, and to record and store the combustion influencing parameters of the coal currently burning in each coal pile obtained by the experimental analysis unit.

4. A coal supply system for a thermal power plant according to claim 3, characterized in that: The heat generation simulation module comprises: The model building unit is used to pre-build a heat generation simulation model, wherein the heat generation simulation model is: Q act =Q tne *(1+F vol +F fix -F moil -F ash -F sul ) Among them, Q act is the actual heat generated, Q the is the theoretical calorific value, F vol is the volatile content, F fix is the fixed carbon fraction, F moil is the moisture value, F ash is the ash value, F sul is the sulfur content; Volatile value Where V is the volatile content data, Q ecvv The equivalent calorific value contributed by the volatile matter during the combustion process is obtained through statistical analysis of experimental data, and the average equivalent calorific value of the volatile matter under different combustion conditions is used as a constant value; Fixed Carbon Score Where FC is the fixed carbon content data, Q ecvf The equivalent calorific value contributed by the fixed carbon in the combustion process is also obtained through experimental data statistics, and the average equivalent calorific value of the fixed carbon under different combustion conditions is used as a constant value; Moisture value Where M is the moisture content data, Q is the heat absorbed by the moisture during the process of heating to the combustion temperature, ham =M*C*(T f -T0), C is the specific heat capacity, T f is the combustion temperature, T0 is the initial temperature; Ash value Where A is the ash content data, Q haa It is the heat absorbed by the ash during the heating process, which is calculated based on the specific heat capacity of the ash, the ash content, and the difference between the combustion temperature and the initial temperature; Q aloss The heat carried away by the residual ash is obtained by statistically analyzing the residual ash ratio and the average heat carried away by the residual ash during the cooling process as a constant value; Sulfur content Where S is the sulfur content data, Q has is the amount of heat absorbed by sulfur during the heating process, which is calculated based on the specific heat capacity of sulfur, sulfur content, and the difference between the combustion temperature and the initial temperature; Q sloss The heat carried away by the sulfur combustion products is obtained through experimental data statistics, and the average heat loss of the sulfur combustion products is used as a constant; The calorific value calculation unit is connected to the data recording unit and the model building unit, and is used to input the combustion influencing parameters into the calorific value simulation model, calculate and output the actual calorific value Q of the coal in each coal pile. act i.

5. A coal supply system for a thermal power plant according to claim 4, characterized in that: The coal bunker matching module includes: A matching decision unit is connected to the calorific value calculation unit and is used to pre-establish a high calorific value threshold range, a medium calorific value threshold range, and a low calorific value threshold range corresponding to the three types of coal bunkers: excellent, medium, and inferior; compare the actual calorific value with the threshold range, determine the coal bunker to which the coal belongs, and generate matching results for each coal pile and the three types of coal bunkers: excellent, medium, and inferior; A transport control unit is connected to the matching decision unit and is used to control the transport equipment to transport the coal in each coal pile to the corresponding coal bunker according to the matching result.

6. A coal supply system for a thermal power plant according to claim 5, characterized in that: The coal quantity allocation module comprises: A factor acquisition unit, which is used to obtain the heat demand data of the current boiler, the storage capacity information of the three types of coal bunkers, the unit coal supply cost of the coal burned in the three types of coal bunkers, and the median of the calorific value threshold range corresponding to the three types of coal bunkers; an optimization allocation unit connected to the factor acquisition unit, which allocates the ideal coal supply amount of each coal bunker to the boiler based on the allocation optimization model and generates an allocation plan; The allocation optimization model is: Objective function: minimizeZ = C A *m A +C B *m B +C C *m C Heat demand constraint: Q dem =m A *Q A +m B *Q B +m C *Q C Non-negative constraint condition for coal supply: m A ≥0,m B ≥0,m C ≥0 m A =λ*P A *(S total -m A -m B -m C ) Proportional constraint: m B =λ*P B *(S total -m A -m B -m C ) m C =λ*P C *(S total -m A -m B -m C ) Among them, minimizeZ represents minimizing cost, C A , C B , C C The unit coal supply costs of three types of coal bunkers, namely, high-quality, medium-quality and low-quality, m A 、m B 、m C are the ideal coal supply of the three types of coal bunkers that need to be determined; Q dem is the current boiler heat demand data, Q A , Q B , Q C are the median values ​​of the calorific value threshold ranges corresponding to the three types of coal bunkers; S total is the sum of the storage capacity of the three types of coal bunkers, that is, S total =S A +S B +S C , where S A , S B , S C are the current storage capacity of the three types of coal bunkers; P A , P B , P C is the scale parameter, that is λ is the proportional adjustment coefficient, which is used to achieve the proportional balance of the storage capacity of the three types of coal bunkers; Determine the ideal coal supply m of three types of coal bunkers by linear programming solution method A 、m B 、m C , generate the current allocation plan.

7. A coal supply system for a thermal power plant according to claim 6, characterized in that: The control module comprises: An instruction generating unit, connected to the optimization allocation unit, generates a corresponding instruction signal based on the current allocation scheme; The equipment control unit is connected to the instruction generating unit and is used to receive the instruction signal, control the start, stop and speed adjustment operation of the conveying equipment according to the instruction signal, and control the discharge valve and baffle equipment of the coal bunker to ensure the accurate distribution and flow control of the coal.

8. A coal supply system for a thermal power plant according to claim 7, characterized in that: The instruction generating unit selects a PID controller, and the generated instruction signal includes the coal supply amount of each coal bin and the randomly generated coal supply sequence information.

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