Ash conveying energy-saving program control method and system

Abstract

The invention relates to the technical field of coal-fired thermal generator set electric precipitation ash conveying energy-saving automatic control, in particular to an ash conveying energy-saving program control method and an ash conveying energy-saving program control system, which realize accurate control and energy-saving optimization of an ash conveying system by analyzing load change, flue gas dust concentration and coal type of a coal-fired thermal generator set. Specifically, the system dynamically calculates the quantity demanded of compressed air according to the difference between the dust concentration and the coal type, selects a proper ash conveying program control mode, and reasonably adjusts the number of air compressors and the number of ash conveying channels, so that the compressed air is saved. Through real-time monitoring and dynamic adjustment, the system effectively reduces compressed air waste in the ash conveying process, and experimental data shows that after the system is implemented, the plant energy consumption of a power plant is reduced by 0.03% or above; and meanwhile, the efficient operation of the whole system is also improved through reasonable allocation of the ash conveying units, and remarkable economic benefits and energy optimization effects are brought to a power plant.

Description

Technical Field

[0001] The invention relates to the technical field of energy-saving automatic control of electric dust removal and ash conveying for coal-fired thermal power generating sets, and in particular to an energy-saving program control method and system for ash conveying. Background Art

[0002] Pneumatic conveying is generally used for electrostatic precipitators of coal-fired thermal power generation units. During operation, each ash conveying unit is relatively independent, the number of ash conveying channels is not fixed at the same time, the amount of compressed air for ash conveying is used irregularly, the pressure of the compressed air for ash conveying fluctuates greatly, and when low-ash coal is burned, the compressed air for ash conveying is seriously wasted, affecting the economic operation of the unit.

[0003] By using the test results of ash conveying compressed air pressure corresponding to the combination of ash conveying channels and the number of air compressors, the ash conveying program control transformation is carried out at the same time, thereby realizing energy-saving automatic control of ash conveying in the electrostatic precipitator ash hopper.

[0004] In summary, an ash conveying energy-saving program control method and system is based on an automatic ash conveying energy-saving control strategy for the electrostatic precipitator ash hopper. By conducting experimental research on the combination of ash conveying channels and the number of air compressors, the compressed air demand under different conditions is calculated, and the number of air compressors in operation is optimized in combination with the ash conveying program control system. Specifically, the system monitors the changes in dust concentration and uses the ash-to-gas ratio calculation to ensure the accurate supply of compressed air for ash conveying. In addition, the system has designed a variety of energy-saving modes, and selects the corresponding combination of ash conveying channels and the number of air compressors according to the actual air demand, thereby minimizing the waste of compressed air and reducing plant energy consumption under the premise of ensuring normal ash conveying, thereby achieving energy saving. This energy-saving scheme based on process control has shown good energy-saving effects in the actual application of a power plant in Nantong, Jiangsu, and provides a new idea for improving the efficiency of the ash conveying system of thermal power plants. Summary of the invention

[0005] In view of the above problems existing in the prior art, the present invention is proposed.

[0006] Therefore, the technical problem to be solved by the present invention is: to design a set of logic, when the unit load or the type of coal burned changes, based on the change in dust concentration in the flue gas, use accurate ash-to-gas ratio calculation to obtain the amount of ash-conveying compressed air required to transport this part of the ash, and by selecting the corresponding ash-conveying operation mode, reasonably adjust the number of ash-conveying air compressors to achieve energy saving.

[0007] To solve the above technical problems, the present invention provides the following technical solutions, a method for energy-saving ash conveying program control, comprising: determining the load change of the coal-fired thermal power unit, calculating the flue gas dust concentration and obtaining the ash-to-gas ratio; determining the air demand for different types of coal, and selecting the ash conveying program control mode; adjusting the number of air compressors and setting the channel quantity limit; real-time monitoring and adjustment of ash conveying system parameters.

[0008] As a preferred embodiment of the ash conveying energy-saving program control method described in the present invention, the determination of the load change of the coal-fired thermal power unit includes confirming the type of coal currently burned and the load conditions during the operation of the generator set, and monitoring according to specific conditions.

[0009] As a preferred scheme of the ash conveying energy-saving program control method described in the present invention, the calculation of flue gas dust concentration and deriving the ash-to-gas ratio includes calculating the amount of compressed air required for the current ash amount through the ash-to-gas ratio formula based on the detected coal load changes and dust concentration.

[0010] As a preferred scheme of the ash conveying energy-saving programmable control method described in the present invention, wherein: the selection of the ash conveying programmable control mode includes selecting the ash conveying mode according to the calculated compressed air demand, presetting the normal mode and the energy-saving mode in the ash conveying programmable control system, and automatically switching according to the compressed air demand.

[0011] As a preferred solution of the ash conveying energy-saving program control method described in the present invention, the adjustment of the number of air compressors includes selecting a suitable number of air compressors to meet the ash conveying demand of the current mode, and determining the number of air compressors by allocating the compressed air demand.

[0012] As a preferred solution of the ash conveying energy-saving program control method described in the present invention, the setting of channel number limit includes setting the current ash conveying channel number according to the selected ash conveying mode, and adjusting the maximum ash conveying channel number according to the compressed air demand.

[0013] As a preferred scheme of the ash conveying energy-saving programmable control method described in the present invention, the real-time monitoring and adjustment of the ash conveying system parameters includes monitoring the key indicators of the ash conveying process, including pressure changes and the operation status of the ash conveying channel, through the real-time monitoring function of the system; if the situation is abnormal, the system automatically adjusts the operation mode and the number of air compressors.

[0014] Another object of the present invention is to provide an ash conveying energy-saving programmable control system. By designing a set of logic, when the unit load or the type of coal burned changes, it can deduce the required ash conveying compressed air volume based on the change in dust concentration in the flue gas by using accurate ash-to-gas ratio calculation, and by selecting the corresponding ash conveying operation mode, reasonably adjust the number of air compressors, thereby achieving energy saving effects.

[0015] In order to solve the above technical problems, the present invention provides the following technical solutions: an ash conveying energy-saving program control system, comprising: a load detection module, a mode selection module, an equipment adjustment module and a real-time monitoring module;

[0016] The load detection module determines the load change of the coal-fired thermal power unit, calculates the flue gas dust concentration and obtains the ash-to-gas ratio;

[0017] The mode selection module determines the air demand of different coal types and selects the ash conveying program control mode;

[0018] The equipment adjustment module adjusts the number of air compressors and sets the channel quantity limit;

[0019] The real-time monitoring module monitors and adjusts the parameters of the ash conveying system in real time.

[0020] A computer device includes a memory and a processor, wherein the memory stores a computer program, and is characterized in that when the processor executes the computer program, the steps of the above-mentioned ash conveying energy-saving program control method are implemented.

[0021] A computer-readable storage medium stores a computer program thereon, wherein when the computer program is executed by a processor, the steps of the above-mentioned ash conveying energy-saving program-controlled method are implemented.

[0022] The beneficial effects of the present invention are as follows: accurate control and energy-saving optimization of the ash conveying system are achieved, and the waste of compressed air in the ash conveying process of the power plant is effectively reduced by calculating the demand for compressed air and combining it with real-time adjustment of the ash conveying program control mode. Specifically, the system can dynamically adjust the ash conveying mode according to changes in dust concentration in the flue gas and different types of coal, ensuring that the use of compressed air is minimized while meeting the system operation requirements. This improvement has significantly improved the economic benefits of the power plant. Experimental data show that after the implementation of the present invention, the power plant's energy consumption has been reduced by more than 0.03%. In addition, the invention rationally allocates different ash conveying units to achieve efficient and energy-saving operation of the system, providing a good optimization solution for the overall energy utilization of the power plant. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0024] Figure 1 A flow chart of an ash conveying energy-saving program-controlled method provided by one embodiment of the present invention.

[0025] Figure 2 A statistical curve chart of ash conveying compressed air pressure test corresponding to the combination of ash conveying channels and the number of air compressors of an ash conveying energy-saving programmable control method provided by one embodiment of the present invention.

[0026] Figure 3 The present invention provides an operating process diagram of an ash conveying energy-saving program-controlled method according to an embodiment of the present invention.

[0027] Figure 4 A step diagram of a silo pump in a power plant unit of an ash conveying energy-saving programmable control method provided by an embodiment of the present invention.

[0028] Figure 5 A counting diagram of an ash conveying energy-saving program-controlled method provided by an embodiment of the present invention.

[0029] Figure 6 An operating quantity diagram of an ash conveying energy-saving program-controlled method provided by an embodiment of the present invention.

[0030] Figure 7 An operating mode diagram of an ash conveying energy-saving program-controlled method provided by an embodiment of the present invention.

[0031] Figure 8 A power plant setting diagram of an ash conveying energy-saving program-controlled method provided by an embodiment of the present invention.

[0032] Fig. 9 This is a screen diagram of a mode selection ash conveying control system of an ash conveying energy-saving program control method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0034] Example 1, reference Figure 1 , is an embodiment of the present invention, which provides an energy-saving program-controlled method for ash conveying, comprising:

[0035] S1: Determine the load change of coal-fired thermal power units, calculate the flue gas dust concentration and obtain the ash-to-gas ratio.

[0036] It should be noted that if Figure 1 As shown in S1, determining the load change of the coal-fired thermal power unit includes confirming the currently burned coal type and load conditions during the operation of the generator set, and monitoring according to specific conditions; calculating the flue gas dust concentration and obtaining the ash-to-gas ratio includes calculating the amount of compressed air required for the current ash amount through the ash-to-gas ratio formula based on the detected coal type load change and dust concentration.

[0037] Furthermore, for the two 1050MW supercritical coal-fired units in Nantong Power Plant, Jiangsu Province, the DCS adds holographic input of coal types for the pulverizer, calculates the ash-gas ratio, and obtains the transported compressed air volume. The calculation formula for the total ash volume of the electrostatic precipitator is:

[0038]

[0039] Among them, B is the total coal consumption, A is the average ash content of coal entering the furnace, η is the electrostatic precipitator efficiency, and α is the proportion of ash in the coal entering the electrostatic precipitator;

[0040] The formula for calculating the compressed air demand is:

[0041]

[0042] Where Q is the compressed air demand (m 3 / min), Gfh is the total ash content of the electrostatic precipitator (T / h), C is the average ash-to-gas ratio, and ρ is the air density under normal conditions (kg / m 2 ).

[0043] Example 2, reference Figure 1-Figure 2 , is an embodiment of the present invention, which provides an energy-saving program-controlled method for ash conveying, comprising:

[0044] S2: Determine the air demand for different types of coal and select the ash conveying program control mode.

[0045] It should be noted that if Figure 1 As shown in S2, selecting the ash conveying program control mode includes selecting the ash conveying mode according to the calculated compressed air demand, presetting the normal mode and the energy-saving mode in the ash conveying program control system, and automatically switching according to the compressed air demand.

[0046] Furthermore, according to the number of ash conveying channels, a mode module selection is added to the ash conveying program control screen, which is divided into "normal mode", "energy-saving mode 1", "energy-saving mode 2" and "energy-saving mode 3". Using the "compressed air demand calculation formula" Q and the "single air compressor output" Q 额 comparative judgment;

[0047] The details are as follows:

[0048] Q>Q 额 *2 When the ash conveying program control is selected as "normal mode", there is no limit on the number of ash conveying channels;

[0049] Q 额 *1.5 <Q≤Q 额 *2 The ash conveying program control selects "Energy Saving Mode 1", and the number of ash conveying channels is limited to 3;

[0050] Q 额 *1 <Q≤Q 额 *1.5 The ash conveying program control selects "Energy Saving Mode 2", and the number of ash conveying channels is limited to 2;

[0051] Q≤Q 额*1 The ash conveying program control selects "Energy Saving Mode 3", and the number of ash conveying channels is limited to 1.

[0052] Furthermore, the parameters of the silo pumps of each ash conveying unit in "normal mode" are set as shown in Table 1 below:

[0053] Table 1 Parameters of silo pumps in each ash conveying unit under "normal mode"

[0054]

[0055] The parameter settings of the silo pumps of each ash conveying unit in "Energy Saving Mode 1" are shown in Table 2 below:

[0056] Table 2 Parameters of silo pumps in each ash conveying unit under "Energy Saving Mode 1"

[0057]

[0058] The parameter settings of the silo pumps of each ash conveying unit in "Energy Saving Mode 2" are shown in Table 3 below:

[0059] Table 3 Parameters of silo pumps in each ash conveying unit under "Energy Saving Mode 2"

[0060]

[0061] The parameter settings of the silo pumps of each ash conveying unit in "Energy Saving Mode 3" are shown in Table 4 below:

[0062] Table 4 Parameters of silo pumps for each ash conveying unit under "Energy Saving Mode 3"

[0063]

[0064] S3: Adjust the number of air compressors and set the channel quantity limit.

[0065] It should be noted that adjusting the number of air compressors includes selecting an appropriate number of air compressors to meet the ash conveying demand of the current mode, and determining the number of air compressors by allocating the compressed air demand; setting the channel number limit includes setting the current number of ash conveying channels according to the selected ash conveying mode, and adjusting the maximum number of ash conveying channels according to the compressed air demand.

[0066] Furthermore, the calculated compressed air volume is used to deduce the number of operating ash conveying air compressors (compressed air demand divided by the rated output of the conveying air compressor); according to the number of operating ash conveying air compressors, the maximum number of ash conveying channels that can meet the ash conveying pressure is determined, such as Figure 2 As shown in Table 5:

[0067] Table 5 Statistical table of ash conveying compressed air pressure test corresponding to the combination of ash conveying channels and air compressors

[0068]

[0069]

[0070] Example 3, reference Figure 3-Figure 9 , is an embodiment of the present invention, which provides an energy-saving program-controlled method for ash conveying, comprising:

[0071] S4: Monitor and adjust the ash conveying system parameters in real time.

[0072] It should be noted that real-time monitoring and adjustment of ash conveying system parameters includes monitoring key indicators in the ash conveying process, including pressure changes and the operation of the ash conveying channel, through the system's real-time monitoring function; if the situation is abnormal, the system automatically adjusts the operating mode and the number of air compressors.

[0073] Furthermore, the fourteen groups of ash conveying units are integrated into a whole, and the state signal of the air intake valve of the ash conveying unit is used as the judgment of whether the channel is running (the "air intake valve open state signal" is judged as conveying, and the "air intake valve closed state signal" is judged as stopping conveying). When they are running, they can queue up autonomously to meet the needs of energy saving. The mode selection of the ash conveying control system is as follows: Fig. 9 As shown;

[0074] First, sort out the logical requirements and confirm which step in the operation process of each unit can be queued, such as Figure 3 , Figure 4 As shown;

[0075] Then, the counting logic is established to accurately count the number of ash conveying electric fields in operation at this time, such as Figure 5 , Figure 6 As shown;

[0076] Set the limit conditions by quantity, and then confirm the operation mode by selecting the screen, such as Figure 7 As shown;

[0077] Set different timers for different electric fields (taking the first electric field as an example), and confirm the continuity of the electric field operation by the length of the timer. For electric fields with more ash, the timer is shorter to reduce the number of queues and ensure complete ash delivery. Figure 8 shown.

[0078] The above is a schematic scheme of a ash conveying energy-saving program-controlled method of this embodiment. It should be noted that the technical scheme of the system of this ash conveying energy-saving program-controlled method and the technical scheme of the above-mentioned ash conveying energy-saving program-controlled method belong to the same concept. The details of the technical scheme of the ash conveying energy-saving program-controlled system not described in detail in this embodiment can all be referred to the description of the technical scheme of the above-mentioned ash conveying energy-saving program-controlled method.

[0079] Embodiment 4 is an embodiment of the present invention, which provides an ash conveying energy-saving program control system, including: a load detection module, a mode selection module, an equipment adjustment module and a real-time monitoring module;

[0080] The load detection module determines the load change of the coal-fired thermal power unit, calculates the flue gas dust concentration and obtains the ash-to-gas ratio;

[0081] The mode selection module determines the air demand of different coal types and selects the ash conveying program control mode;

[0082] The equipment adjustment module adjusts the number of air compressors and sets the channel quantity limit;

[0083] The real-time monitoring module monitors and adjusts the parameters of the ash conveying system in real time.

[0084] This embodiment also provides a computing device, which is applicable to a ash conveying energy-saving program control method, including:

[0085] Memory and processor; the memory is used to store computer executable instructions, and the processor is used to execute computer executable instructions to implement a ash conveying energy-saving program control method as proposed in the above embodiment.

[0086] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, a ash conveying energy-saving program control method as proposed in the above embodiment is implemented.

[0087] The storage medium proposed in this embodiment and the ash conveying energy-saving program control method proposed in the above embodiment belong to the same inventive concept. The technical details not fully described in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0088] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0089] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0090] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0091] 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 preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A ash conveying energy-saving program control method, characterized in that: include: Determine the load change of coal-fired thermal power units, calculate the dust concentration of flue gas and obtain the ash-to-gas ratio; Determine the air requirements for different types of coal and select the ash conveying program control mode; Adjust the number of air compressors and set channel quantity limits; Monitor and adjust ash conveying system parameters in real time.

2. A ash conveying energy-saving program control method as claimed in claim 1, characterized in that: The determination of the load change of the coal-fired thermal power unit includes confirming the type of coal currently burned and the load condition during the operation of the generator set, and monitoring according to specific conditions.

3. A ash conveying energy-saving program control method as claimed in claim 2, characterized in that: The calculation of the flue gas dust concentration and the ash-to-gas ratio includes calculating the amount of compressed air required for the current ash amount through the ash-to-gas ratio formula according to the detected coal type load change and dust concentration.

4. A ash conveying energy-saving program control method as claimed in claim 3, characterized in that: The selection of the ash conveying program control mode includes selecting the ash conveying mode according to the calculated compressed air demand, presetting the normal mode and the energy-saving mode in the ash conveying program control system, and automatically switching according to the compressed air demand.

5. The energy-saving program-controlled method for ash conveying according to claim 4, characterized in that: The adjusting the number of air compressors includes selecting a suitable number of air compressors to meet the ash conveying demand of the current mode, and determining the number of air compressors by allocating the compressed air demand.

6. A ash conveying energy-saving program control method as claimed in claim 5, characterized in that: The setting of the channel quantity limit includes setting the current ash conveying channel quantity according to the selected ash conveying mode, and adjusting the maximum ash conveying channel quantity according to the compressed air demand.

7. A ash conveying energy-saving program control method as claimed in claim 6, characterized in that: The real-time monitoring and adjustment of the ash conveying system parameters includes monitoring key indicators of the ash conveying process, including pressure changes and the operation of the ash conveying channel, through the real-time monitoring function of the system; If the situation is abnormal, the system will automatically adjust the operating mode and the number of air compressors.

8. A ash conveying energy-saving program control system based on any one of claims 1 to 7, characterized in that: include: Load detection module, mode selection module, equipment adjustment module and real-time monitoring module; The load detection module determines the load change of the coal-fired thermal power unit, calculates the flue gas dust concentration and obtains the ash-to-gas ratio; The mode selection module determines the air demand of different coal types and selects the ash conveying program control mode; The equipment adjustment module adjusts the number of air compressors and sets the channel quantity limit; The real-time monitoring module monitors and adjusts the parameters of the ash conveying system in real time.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the ash conveying energy-saving program control method described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of a ash conveying energy-saving program-controlled method described in any one of claims 1 to 7 are implemented.

Images