Optimized operation method and system for solving high-temperature corrosion problem of coal-fired power plant boiler

Abstract

The invention discloses an optimized operation method and system for solving the high-temperature corrosion problem of a coal-fired power plant boiler. Acquiring continuous high-sulfur coal blending combustion time information, historical longest high-sulfur coal blending combustion time information, designed longest high-sulfur coal blending combustion time information, actual accumulated average operation oxygen amount of the boiler, weighted as-fired coal sulfur content, designed boiler operation oxygen amount and designed as-fired coal sulfur content of the boiler to be optimized; if the continuous high-sulfur coal blending combustion time information is equal to the target longest high-sulfur coal blending combustion time information, a high-sulfur coal blending combustion amount reduction initial instruction under the high-load working condition is set; if the actual accumulated average operation oxygen amount of the boiler is smaller than the designed boiler operation oxygen amount, a first correction index is calculated; if the weighted as-fired coal sulfur content is greater than the designed as-fired coal sulfur content, calculating a second correction index; and finally, calculating a high-sulfur coal blending combustion amount reduction output instruction under the high-load working condition, and adjusting the high-sulfur coal blending combustion amount of the boiler. The high-sulfur coal blending combustion operation condition of the coal-fired boiler under the long-time high-load working condition can be effectively controlled, and the high-temperature corrosion problem is remarkably relieved.

Description

Technical Field

[0001] The present invention relates to the technical field of operation optimization, and in particular to an operation optimization method and system thereof for high temperature corrosion problems of coal-fired power station boilers. Background Art

[0002] The high-temperature corrosion problem of coal-fired power plant boilers generally refers to the phenomenon that the sulfur in the coal generates a corrosive ash layer and a corrosive atmosphere during the combustion process, which causes the surface of the metal pipes on the high-temperature heating surface to be corroded. The high-temperature corrosion problem is a common safety problem in coal-fired boilers at present, especially when low-nitrogen combustion technology, deep low-nitrogen combustion technology and high-sulfur coal are used. According to existing research results, the corrosive gases (such as SO3, H2S, HCl, etc.) generated by combustion in the furnace are the main factors causing high-temperature corrosion problems, and the sulfur content in the coal entering the furnace is the fundamental reason for determining the concentration of the main corrosive gases (SO3, H2S) in the flue gas, and the amount of high-sulfur coal blended is one of the main reasons for whether the sulfur content of the coal entering the furnace increases.

[0003] At present, coal-fired power station boilers usually rely on manual confirmation of the high-sulfur coal blending ratio entering the furnace, and as the boiler operation time increases, the coal blending principle entering the furnace remains basically unchanged. That is, after a long period of high-sulfur coal blending operation, the high-sulfur coal blending ratio cannot be automatically adjusted according to the operating conditions. There is a problem that is not conducive to alleviating the development of high-temperature corrosion, which needs further improvement. Summary of the invention

[0004] In order to solve the problem of high temperature corrosion of coal-fired power station boilers in the prior art, the purpose of the present invention is to provide an optimized operation method and system for the high temperature corrosion problem of coal-fired power station boilers, so as to solve the problem that the prior art is not conducive to alleviating the high temperature corrosion of boilers.

[0005] In a first aspect, the present invention provides an optimized operation method for high temperature corrosion of a coal-fired power station boiler, comprising the following steps:

[0006] Obtain the high-sulfur coal blending parameters of the boiler to be optimized within a maintenance cycle, including the continuous high-sulfur coal blending time information under high-load conditions, the longest high-sulfur coal blending time information in history, the designed longest high-sulfur coal blending time information, the actual cumulative average operating oxygen content of the boiler, the weighted sulfur content of the coal entering the furnace, the designed boiler operating oxygen content and the designed boiler entering the furnace coal sulfur content;

[0007] If the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information, an initial instruction for reducing the amount of high-sulfur coal blending under high-load conditions is set;

[0008] If the actual cumulative average operating oxygen content of the boiler is less than the designed operating oxygen content of the boiler, a first correction index is calculated according to the actual cumulative average operating oxygen content of the boiler and the designed operating oxygen content of the boiler;

[0009] If the weighted sulfur content of the coal entering the furnace is greater than the designed sulfur content of the coal entering the boiler, a second correction index is calculated according to the weighted sulfur content of the coal entering the furnace and the designed sulfur content of the coal entering the boiler;

[0010] According to the initial instruction for reducing the amount of high-sulfur coal blended under the high-load condition and the first correction index and the second correction index, an output instruction for reducing the amount of high-sulfur coal blended under the high-load condition is calculated, and the amount of high-sulfur coal blended in the boiler is adjusted according to the output instruction.

[0011] Furthermore, the first correction index X1=(DO-AO) / DO; wherein AO is the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period, and DO is the designed boiler operating oxygen content.

[0012] Furthermore, the second correction index X2 = (AS-DS) / DS; wherein AS is the weighted sulfur content of the coal entering the furnace, and DS is the designed sulfur content of the coal entering the boiler.

[0013] Furthermore, under high-load conditions, the output instruction for reducing the amount of high-sulfur coal blended combustion is F11=F10*(1+aX1+bX2), wherein F10 is the initial instruction for reducing the amount of high-sulfur coal blended combustion under load conditions, X1 is the first correction index, X2 is the second correction index, a is the first correction coefficient, and b is the second correction coefficient.

[0014] Furthermore, the target maximum high-sulfur coal blending time information is used to describe the minimum value between the historical maximum high-sulfur coal blending time information and the designed maximum high-sulfur coal blending time information.

[0015] Furthermore, before setting an initial instruction to reduce the amount of high-sulfur coal blending under high-load conditions if the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information, the method further includes:

[0016] Generate warning maximum high-sulfur coal blending time information according to the target maximum high-sulfur coal blending time information and the preset warning time information, wherein the warning maximum high-sulfur coal blending time information is used to describe the difference between the target maximum high-sulfur coal blending time information and the warning time information;

[0017] Comparing the target maximum high-sulfur coal blending time information with the warning maximum high-sulfur coal blending time information;

[0018] If the continuous high-sulfur coal blending time information is equal to the warning maximum high-sulfur coal blending time information, an initial instruction for pre-reducing the high-sulfur coal blending amount is generated.

[0019] Furthermore, the output instruction F21 for pre-reduction of the amount of high-sulfur coal blended combustion under high-load conditions is, F21=F20*(1+aX1+bX2), wherein F20 is the initial instruction for pre-reduction of the amount of high-sulfur coal blended combustion under high-load conditions, X1 is the first correction index, X2 is the second correction index, a is the first correction coefficient, and b is the second correction coefficient.

[0020] Furthermore, the historical longest high-sulfur coal blending time is the high-load operating time of a single maintenance cycle in history. During this period, no serious high-temperature corrosion problem occurred after the blending of high-sulfur coal. The serious high-temperature corrosion problem refers to the maintenance inspection finding that the heating surface tubes were corroded and thinned by high-temperature corrosion to the point where the requirements for tube replacement are met; the designed maximum high-sulfur coal blending time is the maximum high-sulfur coal blending time under high-load conditions as recommended by the boiler plant or required by regulations.

[0021] A second aspect of the present invention provides an optimized operation system for high temperature corrosion of a coal-fired boiler, comprising:

[0022] The high-sulfur coal blending parameter acquisition module is used to obtain the high-sulfur coal blending parameters of the boiler to be optimized within a maintenance cycle, including the continuous high-sulfur coal blending time information under high-load conditions, the longest high-sulfur coal blending time information in history, the longest designed high-sulfur coal blending time information, the actual cumulative average operating oxygen content of the boiler, the weighted sulfur content of the coal entering the furnace, the designed boiler operating oxygen content and the designed boiler entering the furnace coal sulfur content;

[0023] A module for setting an initial instruction for reducing the amount of high-sulfur coal blending under high-load conditions, for setting and generating an initial instruction for reducing the amount of high-sulfur coal blending under high-load conditions if the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information;

[0024] A first correction index calculation module, configured to calculate a first correction index according to the actual cumulative average operating oxygen content of the boiler and the designed boiler operating oxygen content if the actual cumulative average operating oxygen content of the boiler is less than the designed boiler operating oxygen content;

[0025] A second correction index calculation module is used to calculate a second correction index according to the weighted sulfur content of the coal entering the furnace and the designed sulfur content of the coal entering the boiler if the weighted sulfur content of the coal entering the furnace is greater than the designed sulfur content of the coal entering the boiler;

[0026] The module for calculating the output instruction for reducing the amount of high-sulfur coal blended under high-load conditions is used to calculate the output instruction for reducing the amount of high-sulfur coal blended under high-load conditions based on the initial instruction for reducing the amount of high-sulfur coal blended under high-load conditions and the first correction index and the second correction index, and adjust the amount of high-sulfur coal blended in the boiler according to the output instruction.

[0027] Furthermore, the system also includes a module for setting an initial instruction for pre-reducing the amount of high-sulfur coal blending, and setting an initial instruction for pre-reducing the amount of high-sulfur coal blending includes:

[0028] A warning maximum high-sulfur coal blending time information generation module is used to generate the warning maximum high-sulfur coal blending time information according to the target maximum high-sulfur coal blending time information and the preset warning time information, wherein the warning maximum high-sulfur coal blending time information is used to describe the difference between the target maximum high-sulfur coal blending time information and the warning time information;

[0029] The instruction setting module is used to set an initial instruction for pre-reducing the high-sulfur coal blending amount if the continuous high-sulfur coal blending time information is equal to the warning maximum high-sulfur coal blending time information.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The optimization operation method for the high-temperature corrosion problem of coal-fired power station boilers provided by the present invention first obtains the continuous high-sulfur coal blending time information, the longest high-sulfur coal blending time information in history, the longest designed high-sulfur coal blending time information, the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period, the weighted sulfur content of the coal entering the furnace during the high-sulfur coal blending period, the designed boiler operating oxygen content, the designed boiler entering furnace coal sulfur content and other information of the boiler, and then quickly determines the target longest high-sulfur coal blending time information according to the minimum value of the longest high-sulfur coal blending time information in history and the longest designed high-sulfur coal blending time information, and then compares the target longest high-sulfur coal blending time information with the continuous high-sulfur coal blending time information. If the continuous high-sulfur coal blending time information is equal to the target longest high-sulfur coal blending time information, then timely generates an initial instruction to reduce the high-sulfur coal blending amount, thereby achieving the goal of curbing the generation of corrosive gases such as sulfides and timely curbing the development of high-temperature corrosion; Then, by comparing the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period with the designed boiler operating oxygen content, the first correction index is calculated, and by comparing the weighted sulfur content of the coal entering the furnace during the high-sulfur coal blending period with the designed boiler entering furnace sulfur content, the second correction index is calculated. Finally, according to the initial instruction for reducing the high-sulfur coal blending amount under the high-load condition and the first correction index and the second correction index, the output instruction for reducing the high-sulfur coal blending amount under the high-load condition is calculated, thereby taking into account the influence of the generation of reducing gases such as H2S and CO caused by factors such as insufficient operating oxygen and high sulfur content on high-temperature corrosion. Adjusting the high-sulfur coal blending amount of the boiler according to the calculated high-sulfur coal blending amount reduction output instruction can accurately and effectively alleviate the high-temperature corrosion problem, and to a certain extent avoid the four-tube leakage problem caused by high-temperature corrosion when the current coal-fired boiler blends high-sulfur coal, which plays a positive role in alleviating the high-temperature corrosion problem of the water-cooled wall in the boiler burner area. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0033] Figure 1 is a flow chart of step S200 in the optimization operation method provided by one embodiment of the present invention;

[0034] Figure 2 It is a flowchart of an optimization operation method provided by an embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of the process before step S300 in the optimization operation method provided by one embodiment of the present invention;

[0036] Figure 4 It is a structural diagram of an optimization operation system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0037] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0038] In the description of the present specification and the appended claims, the terms "first", "second", "third" and the like are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0039] References to "one embodiment" or "some embodiments" etc. described in the present specification mean that one or more embodiments of the present invention include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0040] In order to illustrate the technical solution of the present invention, a specific embodiment is provided below for illustration.

[0041] See also Figure 1 , Figure 11 is a flow chart of an optimized operation method for a steam boiler for a coal-fired power plant provided by an embodiment of the present invention. In this embodiment, the execution subject of the optimized operation method is a terminal device. It is understood that the types of terminal devices include but are not limited to mobile phones, tablet computers, notebook computers, ultra-mobile personal computers (Ultra-Mobile Personal Computer, UMPC), netbooks, personal digital assistants (Personal Digital Assistant, PDA), etc., and the embodiments of the present invention do not impose any restrictions on the specific types of terminal devices.

[0042] See also Figure 1 The optimization operation method provided by the embodiment of the present invention includes but is not limited to the following steps:

[0043] In S100, the continuous high-sulfur coal blending time information of the boiler to be optimized under high-load conditions within a single maintenance cycle, the longest high-sulfur coal blending time information in history, the longest designed high-sulfur coal blending time information, the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period, the weighted sulfur content of the coal entering the boiler during the high-sulfur coal blending period, the designed boiler operating oxygen content and the designed boiler entering sulfur content are obtained.

[0044] Specifically, the terminal equipment can first obtain the high-sulfur coal blending parameters of the boiler to be optimized under high-load conditions in a single maintenance cycle, including continuous high-sulfur coal blending time information, the longest high-sulfur coal blending time information in history, the longest designed high-sulfur coal blending time information, the actual cumulative average operating oxygen content of the boiler during high-sulfur coal blending, the weighted sulfur content of the coal entering the furnace during high-sulfur coal blending, the designed boiler operating oxygen content, and the designed boiler entering the furnace coal sulfur content; among them, the boiler to be optimized is used to describe a coal-fired boiler in high-sulfur coal blending operation; the continuous high-sulfur coal blending time information is used to describe the total duration of continuous operation of the boiler to be optimized in the current maintenance cycle; the longest high-sulfur coal blending time information in history is used to describe the longest high-load cumulative operating time of the boiler to be optimized in a high-sulfur coal blending state in a single maintenance cycle in history, without serious high-temperature corrosion problems. The serious high-temperature corrosion problem refers to the inspection and discovery that the heating surface tubes have been thinned by high-temperature corrosion and have reached the requirement for tube replacement; the information on the designed maximum high-sulfur coal blending time is used to describe the longest cumulative high-sulfur coal blending operation time under the high-load condition of the boiler to be optimized; the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period is used to describe the cumulative weighted average of the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period within a single maintenance cycle and under high-load conditions; the weighted sulfur content of the coal entering the furnace during the high-sulfur coal blending period is used to describe the cumulative weighted average of the actual sulfur content of the coal entering the furnace within a single maintenance cycle and under high-load conditions; the designed boiler operating oxygen content is used to describe the designed weighted operating oxygen content under high-load conditions under the boiler design oxygen content operation curve; the designed boiler inlet coal sulfur content is used to describe the designed inlet coal sulfur content value given by the boiler plant.

[0045] Based on the historical longest high-sulfur coal blending time information and the designed longest high-sulfur coal blending time information, the target longest high-sulfur coal blending time information is determined.

[0046] Specifically, after the terminal device obtains the continuous high-sulfur coal blending time information, the historical longest high-sulfur coal blending time information and the designed maximum high-sulfur coal blending time information, the terminal device can quickly determine the target maximum high-sulfur coal blending time information based on the historical longest high-sulfur coal blending time information and the designed maximum high-sulfur coal blending time information, where the target maximum high-sulfur coal blending time information is used to describe the minimum value between the historical longest high-sulfur coal blending time information and the designed maximum high-sulfur coal blending time information.

[0047] See also Figure 1 In some possible implementations, in order to determine the maximum target high sulfur coal blending time information, please refer to Figure 2 The target maximum high-sulfur coal blending time information is obtained through the following process:

[0048] In S210, the historical longest high-sulfur coal blending time information and the designed longest high-sulfur coal blending time information are compared.

[0049] Specifically, the terminal device can first compare the historical longest high-sulfur coal blending time information with the designed longest high-sulfur coal blending time information.

[0050] In S220, if the historical longest high-sulfur coal blending time information is greater than the designed longest high-sulfur coal blending time information, the historical longest high-sulfur coal blending time information is determined as the target longest high-sulfur coal blending time information.

[0051] Specifically, if the historical longest high-sulfur coal blending time information is greater than the designed longest high-sulfur coal blending time information, the terminal device can determine the historical longest high-sulfur coal blending time information as the target longest high-sulfur coal blending time information.

[0052] In S230, if the historical longest high-sulfur coal blending time information is less than the designed longest high-sulfur coal blending time information, the designed longest high-sulfur coal blending time information is determined as the target longest high-sulfur coal blending time information.

[0053] Specifically, if the historical longest high-sulfur coal blending time information is less than the designed longest high-sulfur coal blending time information, the terminal device can determine the designed longest high-sulfur coal blending time information as the target longest high-sulfur coal blending time information.

[0054] In S240, if the historical longest high-sulfur coal blending time information is equal to the designed longest high-sulfur coal blending time information, the historical longest high-sulfur coal blending time information or the designed longest high-sulfur coal blending time information is determined as the target longest high-sulfur coal blending time information.

[0055] Specifically, if the historical longest high-sulfur coal blending time information is equal to the designed longest high-sulfur coal blending time information, the terminal device can determine the historical longest high-sulfur coal blending time information or the designed longest high-sulfur coal blending time information as the target longest high-sulfur coal blending time information.

[0056] See also Figure 2 In S200, the target maximum high-sulfur coal blending time information and the continuous high-sulfur coal blending time information are compared. If the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information, an initial instruction F10 for reducing the amount of high-sulfur coal blending is generated.

[0057] Specifically, if the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information, the terminal device can generate an initial instruction F10 for reducing the high-sulfur coal blending amount, wherein the initial instruction F10 for reducing the high-sulfur coal blending amount is used to indicate a reduction in the high-sulfur coal blending ratio, thereby reducing the situation where the coal-fired boiler continues to be in the high-sulfur coal blending situation, and effectively reducing the high-temperature corrosion risk of the coal-fired boiler.

[0058] In S300, the terminal device compares the actual cumulative average operating oxygen amount AO of the boiler during the high-sulfur coal blending period with the designed boiler operating oxygen amount DO. If the actual cumulative average operating oxygen amount AO of the boiler during the high-sulfur coal blending period is less than the designed boiler operating oxygen amount DO, the terminal device outputs a first correction index X1, wherein X1=(DO-AO) / DO;

[0059] In S400, the terminal device compares the weighted sulfur content of the coal entering the furnace AS during the high-sulfur coal blending period with the designed sulfur content of the coal entering the boiler DS. If the weighted sulfur content of the coal entering the furnace AS is greater than the designed sulfur content of the coal entering the boiler DS, the terminal device outputs a second correction index X2=(AS-DS) / DS;

[0060] In S500, the terminal device calculates the output instruction F11 for reducing the amount of high-sulfur coal blended under high-load conditions based on the initial instruction F10 for reducing the amount of high-sulfur coal blended under high-load conditions and the first correction index X1 and the second correction index X2, where F11=F10*(1+aX1+bX2), wherein the initial value of the first correction coefficient a is 2, and the initial value of the second correction coefficient b is 1, and further corrections are made based on subsequent operating conditions to adjust the amount of high-sulfur coal blended in the boiler based on the output instruction.

[0061] See also Figure 3In order to further reduce the risk of high temperature corrosion in coal-fired boilers, please refer to Figure 3 Before step S300, the method further includes but is not limited to the following steps:

[0062] In S301, warning maximum high-sulfur coal blending time information is generated according to the target maximum high-sulfur coal blending time information and the preset warning time information.

[0063] Specifically, the terminal device can generate the warning maximum high-sulfur coal blending time information based on the difference between the target maximum high-sulfur coal blending time information and the preset warning time information, which is conducive to timely early warning before the high-sulfur coal blending risk accident occurs, wherein the warning maximum high-sulfur coal blending time information is used to describe the difference between the target maximum high-sulfur coal blending time information and the warning time information.

[0064] In S302, the target maximum high-sulfur coal blending time information and the warning maximum high-sulfur coal blending time information are compared.

[0065] Specifically, after the terminal device generates the warning maximum high-sulfur coal blending time information, the terminal device can compare the target maximum high-sulfur coal blending time information with the warning maximum high-sulfur coal blending time information.

[0066] In S303, if the continuous high-sulfur coal blending combustion time information is equal to the warning maximum high-sulfur coal blending combustion time information, a high-sulfur coal blending combustion amount pre-reduction initial instruction F20 is generated.

[0067] Specifically, if the continuous high-sulfur coal blending time information is equal to the warning maximum high-sulfur coal blending time information, the terminal device can generate an initial high-sulfur coal blending amount pre-reduction instruction F20, wherein the high-sulfur coal blending amount pre-reduction instruction F20 is used to indicate a reduction in the fuel supply before executing the high-sulfur coal blending amount reduction instruction, thereby reducing the situation where the coal-fired boiler continues to be in high-sulfur coal blending.

[0068] In some possible implementations, in order to further reduce the high-temperature corrosion risk of coal-fired boilers, the high-sulfur coal blending amount pre-reduction output instruction F21 under high-load conditions is calculated based on the initial instruction F20 for pre-reduction of the high-sulfur coal blending amount under the high-load condition and the first correction index X1 and the second correction index X2, where F21=F20*(1+aX1+bX2), where the initial value of a is 2 and the initial value of b is 1, and they are gradually corrected according to subsequent operating conditions.

[0069] The implementation principle of the method for optimizing the operation of a coal-fired boiler in a coal-fired power plant according to an embodiment of the present invention is as follows: the terminal equipment can first obtain the continuous high-sulfur coal blending time information, the historical longest high-sulfur coal blending time information, the designed longest high-sulfur coal blending time information, the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period, the weighted sulfur content of the coal entering the furnace during the high-sulfur coal blending period, the designed boiler operating oxygen content, the designed boiler entering the furnace and other information of the boiler to be optimized after the unit is put into operation under high-load conditions within a single maintenance cycle, and then quickly determine the target longest high-sulfur coal blending time information based on the minimum value of the historical longest high-sulfur coal blending time information and the designed longest high-sulfur coal blending time information, and then compare the target longest high-sulfur coal blending time information with the continuous high-sulfur coal blending time information. If the continuous high-sulfur coal blending If the burning time information is equal to the target longest high-sulfur coal blending time information, the initial instruction F10 for reducing the amount of high-sulfur coal blending is generated in time; further, by comparing the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period with the designed boiler operating oxygen content, the first correction index X1 is calculated; further, by comparing the weighted sulfur content of the coal entering the furnace during the high-sulfur coal blending period with the designed sulfur content of the coal entering the furnace, the second correction index X2 is calculated; the output instruction F11 for reducing the amount of high-sulfur coal blending is calculated through the initial instruction F10 for reducing the amount of high-sulfur coal blending, the first correction index X1 and the second correction index X2; according to the output instruction F11 for reducing the amount of high-sulfur coal blending, the amount of high-sulfur coal blending in the boiler is adjusted, thereby reducing the long-term high-sulfur coal blending operation of the coal-fired boiler, and effectively alleviating the problem of high-temperature corrosion of the boiler.

[0070] It should be noted that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0071] The embodiment of the present invention further provides an optimized operation system for a coal-fired boiler in a coal-fired power plant. For ease of description, only the parts related to the present invention are shown. Figure 4 As shown, the system includes:

[0072] The high-sulfur coal blending parameter acquisition module is used to obtain the high-sulfur coal blending parameters of the boiler to be optimized within a maintenance cycle, including the continuous high-sulfur coal blending time information under high-load conditions, the longest high-sulfur coal blending time information in history, the longest designed high-sulfur coal blending time information, the actual cumulative average operating oxygen content of the boiler, the weighted sulfur content of the coal entering the furnace, the designed boiler operating oxygen content and the designed boiler entering the furnace coal sulfur content;

[0073] A high-sulfur coal blending amount reduction initial instruction setting module is used to set and generate an initial instruction for reducing the high-sulfur coal blending amount under a high-load condition if the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information;

[0074] A first correction index calculation module, configured to calculate a first correction index according to the actual cumulative average operating oxygen content of the boiler and the designed boiler operating oxygen content if the actual cumulative average operating oxygen content of the boiler is less than the designed boiler operating oxygen content;

[0075] A second correction index calculation module is used to calculate a second correction index according to the weighted sulfur content of the coal entering the furnace and the designed sulfur content of the coal entering the boiler if the weighted sulfur content of the coal entering the furnace is greater than the designed sulfur content of the coal entering the boiler;

[0076] The high-sulfur coal blending amount reduction output instruction calculation module is used to calculate the high-sulfur coal blending amount reduction output instruction under high-load conditions based on the high-sulfur coal blending amount reduction initial instruction and the first correction index and the second correction index under the high-load conditions, and adjust the high-sulfur coal blending amount of the boiler according to the output instruction.

[0077] Optionally, the system further includes a module for setting an initial instruction for pre-reducing the amount of high-sulfur coal blending, and the initial instruction for pre-reducing the amount of high-sulfur coal blending includes:

[0078] A warning maximum high-sulfur coal blending time information generation module is used to generate the warning maximum high-sulfur coal blending time information according to the target maximum high-sulfur coal blending time information and the preset warning time information, wherein the warning maximum high-sulfur coal blending time information is used to describe the difference between the target maximum high-sulfur coal blending time information and the warning time information;

[0079] The instruction setting module is used to set an initial instruction for pre-reducing the high-sulfur coal blending amount if the continuous high-sulfur coal blending time information is equal to the warning maximum high-sulfur coal blending time information.

[0080] Example 1

[0081] A 1000MW ultra-supercritical unit boiler has been running continuously for 500 days, of which the cumulative operation time under high load conditions is 200 days. In order to alleviate the high-temperature corrosion problem of the boiler, the optimization operation method steps are as follows:

[0082] (1) First, obtain the continuous high-sulfur coal blending time information (200 days) of the boiler to be optimized under high-load conditions, the longest high-sulfur coal blending time information in history (200 days), the longest designed high-sulfur coal blending time information (220 days), the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period is 2.5%, the weighted sulfur content of the coal entering the furnace during the high-sulfur coal blending period is 1.2%, the designed boiler operating oxygen content is 3%, and the designed boiler entering the furnace coal sulfur content is 0.8%; the original high-sulfur coal cumulative blending amount is 50t / h (the cumulative average high-sulfur coal blending amount at a high load of more than 75%, and the cumulative average total fuel amount is about 320t / h);

[0083] (2) according to the minimum value of 200 days between the historical longest high-sulfur coal blending time information and the designed longest high-sulfur coal blending time information, determining the target longest high-sulfur coal blending time information to be 200 days;

[0084] (3) comparing the target maximum high-sulfur coal blending time information of 200 days with the continuous high-sulfur coal blending time information of 200 days, and when the difference between the two is 0, proceed to the next step;

[0085] (4) If the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information, an initial instruction F10 for reducing the amount of high-sulfur coal blending is generated (the initial reduction amount is 10 t / h);

[0086] (5) Comparing the actual cumulative average operating oxygen amount AO of the boiler during the high-sulfur coal blending period with the designed boiler operating oxygen amount DO, the actual cumulative average operating oxygen amount AO of the boiler during the high-sulfur coal blending period is less than the designed boiler operating oxygen amount DO, outputting a first correction index X1, wherein X1=(3%-2.5%) / 3%=0.167; comparing the weighted sulfur content of the coal entering the furnace AS during the high-sulfur coal blending period with the designed boiler input coal sulfur content DS, the weighted sulfur content of the coal entering the furnace AS is greater than the designed boiler input coal sulfur content DS, then outputting a second correction index X2=(1.2%-0.8%) / 0.8%=0.5;

[0087] (6) According to the initial instruction F10 for reducing the amount of high-sulfur coal blending under high-load conditions, the first correction index X1, and the second correction index X2, the output instruction F11 for reducing the amount of high-sulfur coal blending under high-load conditions is calculated: F11 = 10 t / h*(1+2*0.167+1*0.5) = 18.34 t / h. After the amount of high-sulfur coal blending is reduced, the concentration of corrosive gases such as hydrogen sulfide and sulfur trioxide generated in the main burner area is significantly reduced, which plays a positive role in alleviating the high-temperature corrosion problem of the water-cooled wall in the boiler burner area.

[0088] It should be noted that the information interaction, execution process and other contents between the above modules are based on the same concept as the embodiment of the method of the present invention. Their specific functions and technical effects can be found in the method embodiment part and will not be repeated here.

[0089] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, all equivalent changes made according to the methods, principles, and structures of the present invention should be included in the protection scope of the present invention.

Claims

1. An optimized operation method for high temperature corrosion of coal-fired boilers, characterized in that: include: Obtain the high-sulfur coal blending parameters of the boiler to be optimized within a maintenance cycle, including the continuous high-sulfur coal blending time information under high-load conditions, the longest high-sulfur coal blending time information in history, the designed longest high-sulfur coal blending time information, the actual cumulative average operating oxygen content of the boiler, the weighted sulfur content of the coal entering the furnace, the designed boiler operating oxygen content and the designed boiler entering the furnace coal sulfur content; If the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information, an initial instruction for reducing the amount of high-sulfur coal blending under high-load conditions is set; If the actual cumulative average operating oxygen content of the boiler is less than the designed operating oxygen content of the boiler, a first correction index is calculated according to the actual cumulative average operating oxygen content of the boiler and the designed operating oxygen content of the boiler; If the weighted sulfur content of the coal entering the furnace is greater than the designed sulfur content of the coal entering the boiler, a second correction index is calculated according to the weighted sulfur content of the coal entering the furnace and the designed sulfur content of the coal entering the boiler; According to the initial instruction for reducing the amount of high-sulfur coal blended under the high-load condition and the first correction index and the second correction index, an output instruction for reducing the amount of high-sulfur coal blended under the high-load condition is calculated, and the amount of high-sulfur coal blended in the boiler is adjusted according to the output instruction.

2. The method according to claim 1, characterized in that The first correction index X1 = (DO-AO) / DO; wherein AO is the actual cumulative average operating oxygen content of the boiler during the high-sulfur coal blending period, and DO is the designed boiler operating oxygen content.

3. The method according to claim 1, characterized in that: The second correction index X2 = (AS-DS) / DS; wherein AS is the weighted sulfur content of the coal entering the furnace, and DS is the designed sulfur content of the coal entering the boiler.

4. The method according to claim 1, characterized in that Under high-load conditions, the output instruction for reducing the amount of high-sulfur coal blending is F11=F10*(1+aX1+bX2), where F10 is the initial instruction for reducing the amount of high-sulfur coal blending, X1 is the first correction index, X2 is the second correction index, a is the first correction coefficient, and b is the second correction coefficient.

5. The method according to claim 1, characterized in that The target maximum high-sulfur coal blending time information is used to describe the minimum value between the historical maximum high-sulfur coal blending time information and the designed maximum high-sulfur coal blending time information.

6. The method according to claim 1, characterized in that Before setting an initial instruction to reduce the amount of high-sulfur coal blending under high-load conditions if the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information, the method further includes: Generate warning maximum high-sulfur coal blending time information according to the target maximum high-sulfur coal blending time information and the preset warning time information, wherein the warning maximum high-sulfur coal blending time information is used to describe the difference between the target maximum high-sulfur coal blending time information and the warning time information; Comparing the target maximum high-sulfur coal blending time information with the warning maximum high-sulfur coal blending time information; If the continuous high-sulfur coal blending time information is equal to the warning maximum high-sulfur coal blending time information, an initial instruction for pre-reducing the high-sulfur coal blending amount is generated.

7. The method according to claim 6, characterized in that The output instruction F21 for pre-reduction of the amount of high-sulfur coal blended combustion under high-load conditions, F21=F20*(1+aX1+bX2), wherein F20 is the initial instruction for pre-reduction of the amount of high-sulfur coal blended combustion under high-load conditions, X1 is the first correction index, X2 is the second correction index, a is the first correction coefficient, and b is the second correction coefficient.

8. The method according to claim 1, characterized in that: The historical longest high-sulfur coal blending time is the high-load operating time of a single maintenance cycle in history. During this period, no serious high-temperature corrosion problem occurred after the blending of high-sulfur coal. The serious high-temperature corrosion problem refers to the maintenance inspection finding that the heating surface tubes were corroded and thinned by high-temperature corrosion to the point where the requirements for tube replacement are met; the designed maximum high-sulfur coal blending time is the maximum high-sulfur coal blending time under high-load conditions as recommended by the boiler plant or required by regulations.

9. An optimized operation system for high temperature corrosion of coal-fired boilers, characterized in that: include: The high-sulfur coal blending parameter acquisition module is used to obtain the high-sulfur coal blending parameters of the boiler to be optimized within a maintenance cycle, including the continuous high-sulfur coal blending time information under high-load conditions, the longest high-sulfur coal blending time information in history, the longest designed high-sulfur coal blending time information, the actual cumulative average operating oxygen content of the boiler, the weighted sulfur content of the coal entering the furnace, the designed boiler operating oxygen content and the designed boiler entering the furnace coal sulfur content; A high-sulfur coal blending amount reduction initial instruction setting module is used to set and generate an initial instruction for reducing the high-sulfur coal blending amount under a high-load condition if the continuous high-sulfur coal blending time information is equal to the target maximum high-sulfur coal blending time information; A first correction index calculation module, configured to calculate a first correction index according to the actual cumulative average operating oxygen content of the boiler and the designed boiler operating oxygen content if the actual cumulative average operating oxygen content of the boiler is less than the designed boiler operating oxygen content; A second correction index calculation module is used to calculate a second correction index according to the weighted sulfur content of the coal entering the furnace and the designed sulfur content of the coal entering the boiler if the weighted sulfur content of the coal entering the furnace is greater than the designed sulfur content of the coal entering the boiler; The high-sulfur coal blending amount reduction output instruction calculation module is used to calculate the high-sulfur coal blending amount reduction output instruction under high-load conditions based on the high-sulfur coal blending amount reduction initial instruction and the first correction index and the second correction index under the high-load conditions, and adjust the high-sulfur coal blending amount of the boiler according to the output instruction.

10. The system according to claim 9, characterized in that The system also includes a module for setting an initial instruction for pre-reducing the amount of high-sulfur coal blending, and setting an initial instruction for pre-reducing the amount of high-sulfur coal blending includes: A warning maximum high-sulfur coal blending time information generating module is used to generate the warning maximum high-sulfur coal blending time information according to the target maximum high-sulfur coal blending time information and the preset warning time information, wherein the warning maximum high-sulfur coal blending time information is used to describe the difference between the target maximum high-sulfur coal blending time information and the warning time information; The instruction setting module is used to set an initial instruction for pre-reducing the high-sulfur coal blending amount if the continuous high-sulfur coal blending time information is equal to the warning maximum high-sulfur coal blending time information.

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