Intelligent control system and control method for hedge combustion boiler for deep peak regulation

Abstract

The present application relates to the technical field of automatic control of boiler combustion, in particular to a kind of for depth peak shaving of offset combustion boiler intelligent control system and control method, and intelligent control system includes 4 monitoring system modules and 2 control system modules;4 the monitoring system module is respectively flue gas temperature monitoring system, high-temperature heating surface wall temperature deviation monitoring system, flue gas composition monitoring system, superheater desuperheating water monitoring system;2 the control system module is respectively burnout air layer damper control system, burnout air nozzle small air door control system.Can fundamentally solve the problem of flue gas temperature deviation, wall temperature deviation, steam temperature deviation and denitration inlet NO X Left and right deviation in the process of depth peak shaving of offset combustion boiler, monitoring means is complete, control means is accurate, can play the role of advanced regulation, rapid regulation and feedback regulation etc..

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automatic control of boiler combustion, in particular to an intelligent control system and control method for a wall-opposed combustion boiler for deep load regulation. BACKGROUND

[0002] In view of the severe situation of unit load variation and deep load regulation, how to better ensure the safety and economy of unit operation is the most concerned problem of all power generation enterprises. At present, the common means of most power generation enterprises is to obtain suitable pulverizing system operation mode and combustion system air distribution mode under different load and coal conditions by means of boiler combustion adjustment test or operation optimization adjustment, so as to realize the economic operation of the unit under the premise of ensuring safety. There are mainly two prominent problems in the wall-opposed combustion boiler during the unit load variation and deep load regulation: 1) the left and right side steam temperature deviation at the furnace outlet is large, the single side superheater desuperheating water quantity is large, the local area of high temperature heating surface is over-temperature, and the tube burst is caused in severe cases; and 2) the NOx at the denitration inlet is unevenly distributed, the left and right side NOx deviation is large, the ammonia escape rate is high, and the ammonium bisulfate plugging of the air preheater is caused in severe cases. The main reason is that the air distribution mode adjustment of the combustion system is lagging, and the problems of boiler thermal deviation and NOx deviation in the deep load regulation process cannot be effectively solved. X X X

[0003] At present, the change of the overfire air air distribution mode during the boiler combustion adjustment test or operation optimization adjustment is mainly the change of the layer baffle door, and the overfire air small damper is generally manually controlled and generally does not participate in the adjustment during the adjustment operation; meanwhile, the overfire air small damper cannot realize automatic tracking and feedback adjustment under the condition of automatic control without automatic optimization control strategy. SUMMARY

[0004] Therefore, the purpose of the present application is to overcome the defect of the lagging adjustment of the air distribution mode of the combustion system in the prior art, so as to provide an intelligent control system and control method for a wall-opposed combustion boiler for deep load regulation, which can fundamentally solve the problems of large left and right side NOx deviation at the denitration inlet, large left and right side NOx deviation, large left and right side steam temperature deviation at the furnace outlet, and large left and right side wall temperature deviation of the wall-opposed combustion boiler during the deep load regulation. X

[0005] ​​​​To solve the above technical problems, the application provides an intelligent control system for a hedge combustion boiler for deep peak regulation, which comprises four monitoring system modules and two control system modules; the four monitoring system modules are a flue gas temperature monitoring system, a high-temperature heating surface wall temperature deviation monitoring system, a flue gas component monitoring system and a superheater desuperheating water monitoring system; the two control system modules are a layer baffle control system of over-fired air and a small air door control system of over-fired air nozzles; the flue gas temperature monitoring system comprises a right wall infrared flue gas temperature monitoring device and a left wall infrared flue gas temperature monitoring device, the right wall infrared flue gas temperature monitoring device is arranged on the right wall of the furnace, and the left wall infrared flue gas temperature monitoring device is arranged on the left wall of the furnace; the high-temperature heating surface wall temperature deviation monitoring system comprises a screen-type superheater wall temperature monitoring device and a high-temperature superheater wall temperature monitoring device, the screen-type superheater wall temperature monitoring device is used for monitoring the wall temperature of the screen-type superheater, and the high-temperature superheater wall temperature monitoring device is used for monitoring the wall temperature of the high-temperature superheater; the flue gas component monitoring system comprises a plurality of sets of flue gas component monitoring devices arranged in sequence along the width direction of the furnace; the superheater desuperheating water monitoring system comprises a left first-stage desuperheater, a right first-stage desuperheater, a left second-stage desuperheater and a right second-stage desuperheater; the layer baffle control system of over-fired air comprises a left over-fired air layer baffle automatic control device and a right over-fired air layer baffle automatic control device, the layer baffle control system of over-fired air is in communication connection with the flue gas temperature monitoring system and the superheater desuperheating water monitoring system; the small air door control system of over-fired air nozzles comprises a plurality of sets of over-fired air nozzle small air door control devices located at the over-fired air nozzles of the front wall and the rear wall, the flue gas component monitoring devices are in one-to-one correspondence with the number and position of the over-fired air nozzles of the front wall or the over-fired air nozzles of the rear wall, and the small air door control system of over-fired air nozzles is in communication connection with the high-temperature heating surface wall temperature deviation monitoring system, the flue gas component monitoring system and the superheater desuperheating water monitoring system.

[0006] Optionally, the installation height of the right wall infrared flue gas temperature monitoring device and the left wall infrared flue gas temperature monitoring device is located between the upper part of the over-fired air box of the front wall and the bottom of the screen-type superheater, and a cooling and purging system and a soot blowing and decoking system are arranged near the installation position of the right wall infrared flue gas temperature monitoring device and the left wall infrared flue gas temperature monitoring device.

[0007] Optionally, the screen-type superheater wall temperature monitoring device comprises thermocouple sensors and transmitters arranged on the same heat exchange pipe outlet pipe wall of each column of heat exchange pipe screens along the width direction of the furnace, and the number of the screen-type superheater wall temperature monitoring device is the same as the number of columns of heat exchange pipe screens.

[0008] Optionally, the flue gas component monitoring device is arranged between the economizer outlet and the desulfurization system inlet, and the flue gas component monitoring device comprises an online sampling gun, a filtering device, a cooling device, a flue gas NO X analyzer.

[0009] Optionally, the left first-stage desuperheater and the right first-stage desuperheater are arranged between an outlet header of the low-temperature superheater and an inlet header of the screen-type superheater, and the left second-stage desuperheater and the right second-stage desuperheater are arranged between an outlet header of the screen-type superheater and an inlet header of the high-temperature superheater, and the desuperheater water quantity is automatically controlled through the adjusting gate and the flow meter.

[0010] Optionally, the left and right layer baffle automatic control devices of the overfire air are respectively arranged at left and right inlets of the front wall overfire air blower and the rear wall overfire air blower, the baffle is a louver type, and the left and right layer baffle automatic control devices of the overfire air each include a first electric actuator connected with the baffle.

[0011] Optionally, the overfire air nozzle small air door control device corresponds to the front wall overfire air nozzle and the rear wall overfire air nozzle one by one, and the overfire air nozzle small air door control device includes a pull rod and a second electric actuator connected with the pull rod.

[0012] Optionally, the front wall overfire air nozzle and the rear wall overfire air nozzle are each provided with 8, and correspondingly, the flue gas composition monitoring device is provided with 8 sets.

[0013] The application further provides an intelligent control method for the hedge combustion boiler for deep peak regulation, which is applied to the intelligent control system for the hedge combustion boiler for deep peak regulation and includes the following steps:

[0014] S1. According to a unit load instruction, a total coal quantity instruction and a total air quantity instruction, initial setting of a control range of a left-right flue gas temperature deviation, a high-temperature heating surface wall temperature deviation and a left-right desuperheater water quantity deviation is completed.

[0015] S2. The overfire air layer baffle control system adjusts the baffle opening degree according to monitoring results of the right wall infrared flue gas temperature monitoring device and the left wall infrared flue gas temperature monitoring device until the flue gas temperature deviations monitored by the right wall infrared flue gas temperature monitoring device and the left wall infrared flue gas temperature monitoring device are within the control range.

[0016] S3. The overfire air nozzle small air door control system adjusts the air door opening degree according to the high-temperature heating surface wall temperature deviation monitored by the high-temperature heating surface wall temperature monitoring system until the high-temperature heating surface wall temperature deviation monitored by the high-temperature heating surface wall temperature monitoring system is within the control range.

[0017] S4. The overfire air nozzle small air door control system adjusts the air door opening degree according to the NOx deviation monitored by the flue gas composition monitoring device until the NOx deviation monitored by the flue gas composition monitoring device is within the control range. X X S4. The overfire air nozzle small air door control system adjusts the air door opening degree according to the NOx deviation monitored by the flue gas composition monitoring device until the NOx deviation monitored by the flue gas composition monitoring device is within the control range.

[0018] ​S5. The small air door control system of the burnout air injection port controls the air door opening degree adjustment according to the deviation of the desuperheating water amount monitored by the desuperheating water monitoring system of the superheater, until the deviation of the desuperheating water amount monitored by the desuperheating water monitoring system of the superheater is within the control range;

[0019] S6. The above steps S2 to S5 are repeatedly executed after a preset time.

[0020] The technical scheme of the present application has the following advantages:

[0021] The intelligent control system for the hedge combustion boiler for deep peak regulation provided by the present application can fundamentally solve the problems of large deviation of the flue gas temperature at the furnace outlet, the wall temperature, the steam temperature and the NOx concentration at the denitration inlet in the deep peak regulation process of the hedge combustion boiler, the monitoring means is complete, the control means is accurate, and the functions of advanced regulation, rapid regulation and feedback regulation can be played. X BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical scheme in the specific embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the description of the specific embodiments or the prior art. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0023] Figure 1 The figure is a schematic diagram of the intelligent control system for the hedge combustion boiler for deep peak regulation provided in embodiment 1 of the present application.

[0024] Figure 2 The figure is a flow chart of the intelligent control method for the hedge combustion boiler for deep peak regulation provided in embodiment 2 of the present application.

[0025] Legend of the drawings:

[0026] ​1, flue gas temperature monitoring system; 2, overfire damper control system; 3, high temperature heating surface wall temperature deviation monitoring system; 4, overfire air nozzle damper control system; 5, flue gas composition monitoring system; 6, superheater desuperheating water monitoring system; 7, furnace; 8, screen superheater; 9, high temperature superheater; 11, right wall infrared flue gas temperature monitoring device; 12, left wall infrared flue gas temperature monitoring device; 14, low temperature superheater; 15, economizer; 21, left overfire damper automatic control device; 22, right overfire damper automatic control device; 31, screen superheater wall temperature monitoring device; 32, high temperature superheater wall temperature monitoring device; 41, front wall overfire air nozzle; 42, front wall overfire air blast; 43, overfire air nozzle damper control device; 44, rear wall overfire air nozzle; 45, rear wall overfire air blast; 51, flue gas composition monitoring device; 61, left first stage desuperheater; 62, right first stage desuperheater; 63, left second stage desuperheater; 64, right second stage desuperheater; 73, furnace left wall; 74, furnace right wall. DETAILED DESCRIPTION

[0027] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0028] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0029] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0030] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0031] Embodiment 1

[0032] The embodiment provides a hedging combustion boiler intelligent control system for deep peak regulation.

[0033] In one embodiment, as shown in the figure, the intelligent control system comprises 4 monitoring system modules and 2 control system modules; the 4 monitoring system modules are respectively a flue gas temperature monitoring system 1, a high-temperature heating surface wall temperature deviation monitoring system 3, a flue gas component monitoring system 5, and a superheater desuperheating water monitoring system 6; and the 2 control system modules are respectively a burnout air layer baffle control system 2 and a burnout air nozzle small air door control system 4. Figure 1 The flue gas temperature monitoring system 1 comprises a right wall infrared flue gas temperature monitoring device 11 and a left wall infrared flue gas temperature monitoring device 12, the right wall infrared flue gas temperature monitoring device 11 is arranged on the right wall 74 of the furnace, and the left wall infrared flue gas temperature monitoring device 12 is arranged on the left wall 73 of the furnace; the high-temperature heating surface wall temperature deviation monitoring system 3 comprises a screen-type superheater wall temperature monitoring device 31 and a high-temperature superheater wall temperature monitoring device 32, the screen-type superheater wall temperature monitoring device 31 is used for monitoring the wall temperature of the screen-type superheater 8, and the high-temperature superheater wall temperature monitoring device 32 is used for monitoring the wall temperature of the high-temperature superheater 9; the flue gas component monitoring system 5 comprises a plurality of sets of flue gas component monitoring devices 51 arranged in sequence along the width direction of the furnace 7; the superheater desuperheating water monitoring system 6 comprises a left first-stage desuperheater 61, a right first-stage desuperheater 62, a left second-stage desuperheater 63, and a right second-stage desuperheater 64; the burnout air layer baffle control system 2 comprises a left burnout air layer baffle automatic control device 21 and a right burnout air layer baffle automatic control device 22, the burnout air layer baffle control system 2 is in communication connection with the flue gas temperature monitoring system 1 and the superheater desuperheating water monitoring system 6; and the burnout air nozzle small air door control system 4 comprises a plurality of sets of burnout air nozzle small air door control devices 43 located at the front wall burnout air nozzle 41 and the rear wall burnout air nozzle 44, the flue gas component monitoring device 51 is in one-to-one correspondence with the number and position of the burnout air nozzle located at the front wall burnout air nozzle 41 or the rear wall burnout air nozzle 44, and the burnout air nozzle small air door control system 4 is in communication connection with the high-temperature heating surface wall temperature deviation monitoring system 3, the flue gas component monitoring system 5, and the superheater desuperheating water monitoring system 6.

[0034]

[0035] ​In the embodiment, by setting the flue gas temperature monitoring system 1, the high-temperature heating surface wall temperature deviation monitoring system 3, the flue gas component monitoring system 5, the superheater desuperheating water monitoring system 6, the combustion air layer baffle control system 2, the combustion air injection port small air door control system 4, and making the combustion air layer baffle control system 2 in communication connection with the flue gas temperature monitoring system 1 and the superheater desuperheating water monitoring system 6, the combustion air injection port small air door control system 4 in communication connection with the high-temperature heating surface wall temperature deviation monitoring system 3 and the flue gas component monitoring system 5 and the superheater desuperheating water monitoring system 6, when the flue gas temperature deviation monitored by the right wall infrared flue gas temperature monitoring device 11 and the left wall infrared flue gas temperature monitoring device 12 exceeds the control range, for example, the flue gas temperature monitored by the right wall infrared flue gas temperature monitoring device 11 is higher than the flue gas temperature monitored by the left wall infrared flue gas temperature monitoring device 12, the layer baffle on the right side is opened wider and the layer baffle on the left side is closed smaller; when the high-temperature heating surface wall temperature deviation monitoring system 3 monitors that the left and right wall temperature deviations are large, for example, the left side wall temperature is higher than the right side wall temperature, the combustion air injection port air door on the left side is opened wider and the combustion air injection port air door on the right side is closed smaller; when the flue gas component monitoring device 51 monitors that the NOx content on the two sides is large, for example, the NOx content on the left side is higher, the corresponding combustion air injection port small air door on the left side is opened wider; the left side first stage desuperheater 61, the right side first stage desuperheater 62, the left side second stage desuperheater 63 and the right side second stage desuperheater 64 adjust the desuperheating water amount through the automatic adjusting door, the desuperheating water amount is uploaded to the superheater desuperheating water monitoring system 6 through the online flow meter, the left and right side desuperheating water amount deviation automatic calculation and comparison are completed, if the deviation is large, the combustion air layer baffle and the combustion air injection port small air door on the side with high desuperheating water amount are opened wider and the combustion air layer baffle and the combustion air injection port small air door on the side with low desuperheating water amount are closed smaller. Therefore, the intelligent control system can fundamentally solve the problems of the flue gas temperature deviation at the furnace 7 outlet, the wall temperature deviation, the steam temperature deviation and the NOx left and right deviation in the process of the deep peak regulation of the opposite combustion boiler, the monitoring means is complete and the control means is accurate, which can play the roles of the advanced regulation, the rapid regulation and the feedback regulation. X X X Therefore, the intelligent control system can fundamentally solve the problems of the flue gas temperature deviation at the furnace 7 outlet, the wall temperature deviation, the steam temperature deviation and the NOx left and right deviation in the process of the deep peak regulation of the opposite combustion boiler, the monitoring means is complete and the control means is accurate, which can play the roles of the advanced regulation, the rapid regulation and the feedback regulation.

[0036] In the above embodiment, in a preferred embodiment, the installation height of the right wall infrared flue gas temperature monitoring device 11 and the left wall infrared flue gas temperature monitoring device 12 is located between the upper part of the front wall combustion air box and the bottom of the screen superheater 8, and the cooling and purging system and the ash removal and decoking system are arranged near the installation position of the right wall infrared flue gas temperature monitoring device 11 and the left wall infrared flue gas temperature monitoring device 12. In the embodiment, since the installation height of the right wall infrared flue gas temperature monitoring device 11 and the left wall infrared flue gas temperature monitoring device 12 is located between the upper part of the front wall combustion air box and the bottom of the screen superheater 8, after the combustion air layer baffle control system 2 controls the combustion air layer baffle adjustment, the right wall infrared flue gas temperature monitoring device 11 and the left wall infrared flue gas temperature monitoring device 12 can quickly monitor and feedback. ​​

[0037] On the basis of the above-mentioned embodiments, in a preferred embodiment, the wall temperature monitoring device 31 of the platen superheater comprises thermocouple sensors and transmitters arranged along the width direction of the furnace 7 at the same tube wall of the outlet tubes of each row of heat exchange tube panels, and the number of the wall temperature monitoring device 31 of the platen superheater is the same as the number of rows of heat exchange tube panels. In this embodiment, the wall temperature can be more accurately measured, and precise control can be achieved. The arrangement and structure of the wall temperature monitoring device 32 of the high-temperature superheater are consistent with those of the wall temperature monitoring device 31 of the platen superheater.

[0038] On the basis of the above-mentioned embodiments, in a preferred embodiment, the flue gas composition monitoring device 51 is arranged between the economizer 15 outlet and the desulfurization system inlet, and the flue gas composition monitoring device 51 comprises an online sampling gun, a filtering device, a cooling device, a flue gas NO X analyzer.

[0039] On the basis of the above-mentioned embodiments, in a preferred embodiment, the left first-stage desuperheater 61 and the right first-stage desuperheater 62 are arranged between the outlet header of the low-temperature superheater 14 and the inlet header of the platen superheater 8, and the left second-stage desuperheater 63 and the right second-stage desuperheater 64 are arranged between the outlet header of the platen superheater 8 and the inlet header of the high-temperature superheater 9, and the desuperheating water quantity is automatically controlled through the adjusting gate and the flowmeter.

[0040] On the basis of the above-mentioned embodiments, in a preferred embodiment, the left overfire air layer baffle automatic control device 21 and the right overfire air layer baffle automatic control device 22 are respectively located at the left inlet and the right inlet of the front wall overfire air plenum 42 and the rear wall overfire air plenum 45, the baffle is a louver type, and the left overfire air layer baffle automatic control device 21 and the right overfire air layer baffle automatic control device 22 comprise a first electric actuator connected to the baffle.

[0041] On the basis of the above-mentioned embodiments, in a preferred embodiment, the overfire air nozzle small air door control device 43 corresponds to the front wall overfire air nozzle 41 and the rear wall overfire air nozzle 44 one-to-one, and the overfire air nozzle small air door control device 43 comprises a pull rod and a second electric actuator connected to the pull rod. In this embodiment, since the overfire air nozzle small air door control device 43 corresponds to the front wall overfire air nozzle 41 and the rear wall overfire air nozzle 44 one-to-one, the air inlet quantity of each overfire air nozzle can be adjusted, and the adjustment is more precise.

[0042] On the basis of the above-mentioned embodiments, in a preferred embodiment, the front wall overfire air injection ports 41 and the rear wall overfire air injection ports 44 are respectively provided with 8, and correspondingly, the flue gas composition monitoring devices 51 are provided with 8 sets. In other alternative embodiments, the number of the front wall overfire air injection ports 41 and the rear wall overfire air injection ports 44 can be set according to the size of the furnace 7, and the number of the flue gas composition monitoring devices 51 needs to be adjusted correspondingly.

[0043] Embodiment 2

[0044] The embodiment provides an intelligent control method for a hedge combustion boiler for deep peak regulation, which is applied to the intelligent control system for the hedge combustion boiler for deep peak regulation provided in the above-mentioned embodiments, as shown in the figure, and includes the following steps: Figure 2

[0045] S1. The initial setting of the control range of the left and right side flue gas temperature deviation of the furnace 7, the high-temperature heating surface wall temperature deviation, and the left and right side desuperheating water quantity deviation of the superheater is completed according to the unit load instruction, the total coal quantity instruction, and the total air quantity instruction. It should be noted that those skilled in the art can and have the ability to complete the initial setting or adjustment of the control range of the left and right side flue gas temperature deviation of the furnace 7, the high-temperature heating surface wall temperature deviation, and the left and right side desuperheating water quantity deviation of the superheater according to the unit load instruction, the total coal quantity instruction, and the total air quantity instruction, and the embodiment does not limit the initial setting range of the control range of the left and right side flue gas temperature deviation of the furnace 7, the high-temperature heating surface wall temperature deviation, and the left and right side desuperheating water quantity deviation of the superheater.

[0046] S2. The overfire air layer damper control system 2 adjusts the damper opening degree according to the monitoring results of the right wall infrared flue gas temperature monitoring device 11 and the left wall infrared flue gas temperature monitoring device 12 until the flue gas temperature deviation monitored by the right wall infrared flue gas temperature monitoring device 11 and the left wall infrared flue gas temperature monitoring device 12 is within the control range. Specifically, the infrared flue gas temperature monitoring devices of the left and right walls of the furnace 7 automatically monitor the left and right side flue gas temperatures, which are then uploaded to the flue gas temperature monitoring system 1. The overfire air layer damper control system 2 controls the left side overfire air layer damper automatic control device 21 and the right side overfire air layer damper automatic control device 22 to complete the damper opening degree adjustment. The general adjustment principle is to open the damper of the side with higher flue gas temperature and close the damper of the side with lower flue gas temperature. Then, the flue gas temperature deviation is automatically calculated and compared through the flue gas temperature monitoring system 1. If the deviation is within the control range, the next step is entered, otherwise the step is cycled.

[0047] ​S3. The burnout air nozzle damper control system 4 adjusts the damper opening based on the high-temperature heating surface wall temperature deviation monitored by the high-temperature heating surface wall temperature monitoring system until the high-temperature heating surface wall temperature deviation monitored by the high-temperature heating surface wall temperature monitoring system is within the control range. Specifically, the screen-type superheater wall temperature monitoring device 31 and the high-temperature superheater wall temperature monitoring device 32 automatically monitor the outlet wall temperature of the same heat exchange tube in each row of heat exchange tube screens along the width direction of the furnace 7, and then upload it to the high-temperature heating surface wall temperature deviation monitoring system 3 to complete the automatic calculation and comparison of the wall temperature deviation. If the deviation exceeds the control range, the burnout air nozzle damper control system 4 controls the burnout air nozzle damper control device 43 to complete the damper opening adjustment. The general adjustment principle is to open the burnout air nozzle damper at the corresponding position of the high-temperature wall tube screen and close the burnout air nozzle damper at the corresponding position of the low-temperature wall tube screen. Then, the high-temperature heating surface wall temperature deviation monitoring system 3 completes the automatic calculation and comparison of the wall temperature deviation. If the deviation is within the control range, proceed to the next step; otherwise, repeat the same step.

[0048] S4. Combustion air nozzle damper control system 4 based on NO monitored by flue gas composition monitoring device 51 X The deviation control damper opening is adjusted until the NO content is detected by the flue gas composition monitoring device 51. X The deviation is within the control range. Specifically, the flue gas composition monitoring device 51 automatically monitors the NO content in the flue gas along the width of the furnace 7 in the denitrification inlet flue. X Distribution information is then uploaded to the flue gas composition monitoring system 5 to complete the NO distribution analysis. X The deviation is automatically calculated and compared. If the deviation exceeds the control range, the burnout air nozzle small damper control system 4 controls the burnout air nozzle small damper control device 43 to adjust the damper opening, and then the NO content is adjusted by the flue gas composition monitoring system 5. X Deviation is automatically calculated and compared. If the deviation is within the control range, proceed to the next step; otherwise, repeat the process.

[0049] S5. The burnout air nozzle small damper control system 4 adjusts the damper opening based on the desuperheating water volume deviation monitored by the superheater desuperheating water monitoring system 6 until the desuperheating water volume deviation monitored by the superheater desuperheating water monitoring system 6 is within the control range. Specifically, the left first-stage desuperheater 61, the right first-stage desuperheater 62, the left second-stage desuperheater 63, and the right second-stage desuperheater 64 adjust the desuperheating water volume through automatic adjustment gates. The desuperheating water volume is uploaded to the superheater desuperheating water monitoring system 6 through an online flow meter, completing the automatic calculation and comparison of the desuperheating water volume deviation on the left and right sides. If the deviation exceeds the control range, the burnout air nozzle small damper control system 4 controls the burnout air nozzle small damper control device 43 to complete the damper opening adjustment. At the same time, the burnout air layer baffle control system 2 controls the left burnout air layer baffle automatic control device 21 and the right burnout air layer baffle automatic control device 22 to complete the baffle opening adjustment.

[0050] S6. If the deviation in the above S5 step is within the control range, the above S2 to S5 steps are repeatedly executed after a predetermined time. Specifically, the predetermined time can be half an hour.

[0051] Obviously, the above-mentioned embodiments are merely exemplary and are not intended to limit the implementation. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and impossible to exhaust all the implementations. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. An intelligent control system for a dispatchable, oxy-fired, peaking boiler, comprising: It comprises four monitoring system modules and two control system modules; the four monitoring system modules are respectively a flue gas temperature monitoring system (1), a high-temperature heating surface wall temperature deviation monitoring system (3), a flue gas composition monitoring system (5), and a superheater desuperheating water monitoring system (6); the two control system modules are respectively a layer baffle control system of over-fired air (2) and a small air door control system of over-fired air nozzle (4); The flue gas temperature monitoring system (1) comprises a right wall infrared flue gas temperature monitoring device (11) and a left wall infrared flue gas temperature monitoring device (12), wherein the right wall infrared flue gas temperature monitoring device (11) is arranged on the right wall (74) of the furnace, and the left wall infrared flue gas temperature monitoring device (12) is arranged on the left wall (73) of the furnace. The high-temperature heating surface wall temperature deviation monitoring system (3) comprises a screen-type superheater wall temperature monitoring device (31) and a high-temperature superheater wall temperature monitoring device (32), wherein the screen-type superheater wall temperature monitoring device (31) is used for monitoring the wall temperature of the screen-type superheater (8), and the high-temperature superheater wall temperature monitoring device (32) is used for monitoring the wall temperature of the high-temperature superheater (9). The flue gas composition monitoring system (5) comprises multiple sets of flue gas composition monitoring devices (51) arranged in sequence along the width direction of the furnace (7). The superheater desuperheating water monitoring system (6) comprises a left first-stage desuperheater (61), a right first-stage desuperheater (62), a left second-stage desuperheater (63), and a right second-stage desuperheater (64). The layer baffle control system of over-fired air (2) comprises a left layer baffle automatic control device of over-fired air (21) and a right layer baffle automatic control device of over-fired air (22), and is in communication connection with the flue gas temperature monitoring system (1) and the superheater desuperheating water monitoring system (6). The small air door control system of over-fired air nozzle (4) comprises multiple sets of small air door control devices (43) of over-fired air nozzle located at the front wall over-fired air nozzle (41) and the rear wall over-fired air nozzle (44), the number and position of the flue gas composition monitoring devices (51) correspond to the front wall over-fired air nozzle (41) or the rear wall over-fired air nozzle (44) in one-to-one correspondence, and the small air door control system of over-fired air nozzle (4) is in communication connection with the high-temperature heating surface wall temperature deviation monitoring system (3), the flue gas composition monitoring system (5), and the superheater desuperheating water monitoring system (6).

2. The intelligent control system for a dispatchable, oxy-fired, peaking boiler of claim 1, wherein, The installation height of the right wall infrared flue gas temperature monitoring device (11) and the left wall infrared flue gas temperature monitoring device (12) is located between the upper part of the front wall over-fired air box and the bottom of the screen-type superheater (8), and a cooling and purging system and a dust and decoking system are arranged near the installation position of the right wall infrared flue gas temperature monitoring device (11) and the left wall infrared flue gas temperature monitoring device (12).

3. The intelligent control system for a dispatchable, oxy-fired, peaking boiler of claim 1, wherein, The screen-type superheater wall temperature monitoring device (31) comprises thermocouple sensors and transmitters arranged at the outlet pipe wall of each column of heat exchange tube screens along the width direction of the furnace (7), and the number of the screen-type superheater wall temperature monitoring device (31) is the same as the number of columns of heat exchange tube screens.

4. The intelligent control system for a dispatchable, oxy-fired, peaking boiler of claim 1, wherein, The flue gas component monitoring device (51) is arranged between the outlet of the coal economizer (15) and the inlet of the desulfurization system, and comprises an online sampling gun, a filtering device, a cooling device, a flue gas NO X analyzer.

5. The intelligent control system for a dispatchable, oxy-fired, peaking boiler of claim 1, wherein, The left first-stage desuperheater (61) and the right first-stage desuperheater (62) are arranged between the outlet header of the low-temperature superheater (14) and the inlet header of the screen superheater (8), and the left second-stage desuperheater (63) and the right second-stage desuperheater (64) are arranged between the outlet header of the screen superheater (8) and the inlet header of the high-temperature superheater (9), and the desuperheater water quantity is automatically controlled through the adjusting gate and the flowmeter.

6. The intelligent control system for a dispatchable, oxy-fired, peaking boiler of claim 1, wherein, The left and right overfire damper automatic control devices (21) and (22) are respectively located at the left and right inlets of the front wall overfire air plenum (42) and the rear wall overfire air plenum (45), the damper is a louver type, and the left and right overfire damper automatic control devices (21) and (22) comprise a first electric actuator connected with the damper.

7. The intelligent control system for a dispatchable, oxy-fired, peaking boiler of claim 1, wherein, The overfire air nozzle damper control device (43) corresponds to the front wall overfire air nozzle (41) and the rear wall overfire air nozzle (44), and the overfire air nozzle damper control device (43) comprises a pull rod and a second electric actuator connected with the pull rod.

8. The intelligent control system for a dispatchable, oxy-fired, peaking boiler of claim 7, wherein, The front wall overfire air nozzle (41) and the rear wall overfire air nozzle (44) are respectively provided with eight nozzles, and correspondingly, the flue gas composition monitoring device (51) is provided with eight sets of monitoring devices.

9. A method for intelligent control of a CFB boiler for deep peak shaving, characterized in that, The intelligent control system for the hedge combustion boiler for deep peak regulation of any one of claims 1-8 comprises: S1. According to the unit load instruction, the total coal quantity instruction and the total air quantity instruction, the initial setting of the control range of the left and right flue gas temperature deviation of the furnace (7), the high-temperature heating surface wall temperature deviation, and the desuperheater left and right desuperheater water quantity deviation control range is completed; S2. The overfire damper control system (2) adjusts the damper opening degree according to the monitoring results of the right wall infrared flue gas temperature monitoring device (11) and the left wall infrared flue gas temperature monitoring device (12) until the flue gas temperature deviation monitored by the right wall infrared flue gas temperature monitoring device (11) and the left wall infrared flue gas temperature monitoring device (12) is within the control range; S3. The overfire air nozzle damper control system (4) adjusts the damper opening degree according to the high-temperature heating surface wall temperature deviation monitored by the high-temperature heating surface wall temperature monitoring system until the high-temperature heating surface wall temperature deviation monitored by the high-temperature heating surface wall temperature monitoring system is within the control range; S4. The small damper control system (4) of the overfire air nozzle controls the damper opening according to the NOx monitored by the flue gas composition monitoring device (51) X The bias control damper opening is adjusted until the NOx monitored by the flue gas composition monitoring device (51) X The bias is within the control range; S5. The overfire air nozzle damper control system (4) adjusts the damper opening degree according to the desuperheater water quantity deviation monitored by the desuperheater water monitoring system (6) until the desuperheater water quantity deviation monitored by the desuperheater water monitoring system (6) is within the control range; S6. After a preset time, the above steps S2 to S5 are repeatedly executed.

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