CN117490044A - Boiler feed water heating system and method for deep peak shaving unit - Google Patents
Boiler feed water heating system and method for deep peak shaving unit Download PDFInfo
- Publication number
- CN117490044A CN117490044A CN202311717856.6A CN202311717856A CN117490044A CN 117490044 A CN117490044 A CN 117490044A CN 202311717856 A CN202311717856 A CN 202311717856A CN 117490044 A CN117490044 A CN 117490044A
- Authority
- CN
- China
- Prior art keywords
- regulating valve
- feed water
- heater
- valve group
- water supply
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 175
- 238000010438 heat treatment Methods 0.000 title claims abstract description 37
- 238000000034 method Methods 0.000 title claims abstract description 12
- 230000001105 regulatory effect Effects 0.000 claims abstract description 96
- 238000010248 power generation Methods 0.000 claims abstract description 16
- 239000003546 flue gas Substances 0.000 claims description 13
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 12
- 238000010521 absorption reaction Methods 0.000 claims description 10
- 230000001276 controlling effect Effects 0.000 claims description 5
- 230000033228 biological regulation Effects 0.000 description 11
- 238000005485 electric heating Methods 0.000 description 9
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 8
- 230000005611 electricity Effects 0.000 description 5
- 238000000605 extraction Methods 0.000 description 3
- BIGPRXCJEDHCLP-UHFFFAOYSA-N ammonium bisulfate Chemical compound [NH4+].OS([O-])(=O)=O BIGPRXCJEDHCLP-UHFFFAOYSA-N 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 239000002956 ash Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000010531 catalytic reduction reaction Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- -1 flue gas nitrogen oxides Chemical class 0.000 description 1
- 239000010881 fly ash Substances 0.000 description 1
- 239000008236 heating water Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000006722 reduction reaction Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 239000008400 supply water Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B1/00—Methods of steam generation characterised by form of heating method
- F22B1/02—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
- F22B1/18—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
- F22B33/00—Steam-generation plants, e.g. comprising steam boilers of different types in mutual association
- F22B33/18—Combinations of steam boilers with other apparatus
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22D—PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
- F22D1/00—Feed-water heaters, i.e. economisers or like preheaters
- F22D1/50—Feed-water heaters, i.e. economisers or like preheaters incorporating thermal de-aeration of feed-water
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F22—STEAM GENERATION
- F22G—SUPERHEATING OF STEAM
- F22G1/00—Steam superheating characterised by heating method
- F22G1/02—Steam superheating characterised by heating method with heat supply by hot flue gases from the furnace of the steam boiler
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J15/00—Arrangements of devices for treating smoke or fumes
- F23J15/06—Arrangements of devices for treating smoke or fumes of coolers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
- F23L15/00—Heating of air supplied for combustion
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Air Supply (AREA)
- Control Of Steam Boilers And Waste-Gas Boilers (AREA)
Abstract
The invention provides a boiler feed water heating system and a method of a deep peak shaver set, which relate to the technical field of thermodynamic systems and comprise a steam power generation loop, a first regulating valve group, a first feed water branch, a second feed water branch and a third feed water branch, wherein the first regulating valve group, the first feed water branch, the second feed water branch and the third feed water branch are arranged on the steam power generation loop; the first regulating valve group is arranged between the high-pressure heater and the low-temperature economizer; the first water supply branch is connected between the high-pressure heater and the low-temperature economizer and comprises a second regulating valve group and a primary water supply heater; the second water supply branch is connected between the high-pressure heater and the high-temperature economizer and comprises a third regulating valve group and a secondary water supply heater; the third water supply branch is connected between the high-pressure heater and the boiler barrel and comprises a fourth regulating valve group and a three-stage water supply heater; the first regulating valve group, the first, the second and the third water supply branches are used for regulating the water supply temperature entering the low-temperature economizer, the high-temperature economizer and/or the boiler barrel during deep peak shaving. The invention improves the reliability and the deep peak shaving capacity of the system.
Description
Technical Field
The invention relates to the technical field of thermodynamic systems, in particular to a boiler feed water heating system and a boiler feed water heating method for a deep peak shaver set.
Background
In order to adapt to the characteristics of randomness and instability of the power generation output of new energy power such as wind power, photovoltaic and the like, the capacity of absorbing new energy is improved, the peak regulation potential of a thermal power unit needs to be excavated, and the thermal power operation flexibility is improved. In the period of low electricity consumption or high output peak of new energy, the peak shaver set operates under low load, the temperature level of a boiler hearth and the whole flue gas channel is lower than a design value, and the stable combustion capacity of the burner is reduced due to the reduction of the temperature of the hearth; the temperature of the SCR denitration zone is reduced, the denitration efficiency is reduced, and the emission of nitrogen oxides exceeds the standard; the temperature of the air preheater area is reduced, so that ammonia bisulfate in the flue gas is condensed to capture fly ash in the flue gas to cause the blockage of the rotary air preheater, thereby limiting the deep peak regulation capacity of a unit, and the generating capacity of the super-generating unit in the electricity consumption low-valley period is low in cost and the enterprise generation loss is serious.
The prior art generally uses a No. 0 high-pressure adding scheme, and utilizes system steam to heat boiler water supply, and the air source of the scheme generally adopts the air source at the existing air compensating valve or needs to punch and extract steam at a steam turbine (after 5 stages of high-pressure cylinders). However, by adopting a mode of an air source at the air compensating valve, the air source is limited by the form of a turbine of the unit, and the steam turbine is difficult to reform in a punching and steam extracting mode; the heating water supply has higher steam temperature and pressure parameters, and the manufacturing cost of the water supply heater is high; the system needs to be designed into a reasonable steam introducing system of the heater and a drainage system after steam heat exchange, and is complex; in the running process of the scheme, the unit is in a low-load running state, the through-flow steam quantity of the steam turbine is small at the moment, when the required steam extraction quantity is overlarge, the safe and stable running of the steam turbine equipment is easily influenced, and when the steam extraction quantity can not heat the feed water to the expected temperature, the deep peak regulation capacity of the boiler is limited.
Disclosure of Invention
In order to solve the defects of the prior art, the invention aims to provide a boiler water heating system and a boiler water heating method for a depth peak shaver set, so as to overcome the defects of the existing No. 0 high-adding scheme, and improve the system reliability and the depth peak shaver capacity of the system.
In order to achieve the above object, according to some embodiments, a first aspect of the present invention provides a boiler feedwater heating system of a depth peak shaver set, including a steam power generation circuit, and a first regulating valve group, a first feedwater branch, a second feedwater branch, and a third feedwater branch disposed on the steam power generation circuit; the steam power generation loop comprises a deaerator, a high-pressure heater, a low-temperature economizer, a high-temperature economizer, a boiler barrel, a superheater, a steam turbine and a generator which are connected in sequence; the first regulating valve group is arranged between the high-pressure heater and the low-temperature economizer; the first water supply branch is connected between the high-pressure heater and the low-temperature economizer and comprises a second regulating valve group and a primary water supply heater; the second water supply branch is connected between the high-pressure heater and the high-temperature economizer and comprises a third regulating valve group and a secondary water supply heater; the third water supply branch is connected between the high-pressure heater and the boiler barrel and comprises a fourth regulating valve group and a three-stage water supply heater; the first regulating valve group, the first water supply branch, the second water supply branch and the third water supply branch are used for regulating the water supply temperature entering the low-temperature economizer, the high-temperature economizer and/or the boiler barrel during deep peak shaving.
Preferably, the electric heating control system is further comprised, and is connected with the primary feed water heater, the secondary feed water heater and the tertiary feed water heater and is electrically connected with the primary feed water heater, the secondary feed water heater and the tertiary feed water heater.
Preferably, the number of the second regulating valve groups is 2, and the primary feed water heater is positioned between the 2 second regulating valve groups; the number of the third regulating valve groups is 2, and the secondary feedwater heater is positioned between the 2 third regulating valve groups; the number of the fourth regulating valve groups is 2, and the three-stage feed water heater is positioned between the 2 fourth regulating valve groups.
Preferably, the system also comprises an SCR denitration system and an air preheater, wherein the superheater, the high-temperature economizer, the low-temperature economizer, the SCR denitration system and the air preheater are all arranged in a boiler tail flue.
Preferably, temperature sensors are arranged in the SCR denitration system and the air preheater and used for acquiring the flue gas temperature at the SCR denitration system and the air preheater.
Preferably, the low-temperature economizer and the high-temperature economizer are respectively provided with a flowmeter for acquiring medium flow in the low-temperature economizer and the high-temperature economizer; and the outlets of the low-temperature economizer and the high-temperature economizer are respectively provided with a temperature sensor for acquiring the outlet medium temperature of the low-temperature economizer and the high-temperature economizer.
According to a second aspect of the present invention, based on the foregoing first aspect, there is further provided a boiler feedwater heating system of a depth peak shaver set, including:
s1, when the system operates normally, a first regulating valve group is opened, a second regulating valve group, a third regulating valve group and a fourth regulating valve group are closed, and boiler feed water enters the boiler through a water supply main path;
s2, when the temperature of the flue gas does not meet the temperature requirements of an SCR denitration system and/or a rotary air preheater, closing a first regulating valve group, opening a second regulating valve group, and heating boiler feed water by using a primary feed water heater;
s3, when the temperature of the medium at the outlet of the high-temperature economizer reaches a protection fixed value, opening a third regulating valve group, and heating part of boiler feed water through a secondary feed water heater and then feeding the part of boiler feed water into the high-temperature economizer;
and S4, when the medium flow in the low-temperature economizer is reduced to the design limit, opening a fourth regulating valve group, and heating part of boiler feed water through the three-stage feed water heater and then feeding the heated boiler feed water into the boiler barrel.
Preferably, the super-power generation using the generator provides power to the primary, secondary and/or tertiary feedwater heaters.
Preferably, in step S3, the opening degree of the second adjusting valve group and/or the third adjusting valve group and the heating amount of the primary feedwater heater and/or the secondary feedwater heater are controlled, so as to control the medium flow and the temperature in the first feedwater branch and the second feedwater branch, and reduce the heat absorption amount of the boiler feedwater in the low-temperature economizer.
Preferably, in step S4, the opening degrees of the second adjusting valve group, the third adjusting valve group and the fourth adjusting valve group and the heating amounts of the primary feed water heater, the secondary feed water heater and the third feed water heater are controlled, and the medium flow and the temperature in the first feed water branch, the second feed water branch and the third feed water branch are controlled, so that the heat absorption amount of the boiler feed water in the high-temperature economizer is reduced.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a boiler feed water heating system and a method for a deep peak shaving unit, wherein the topology connection relation of the system can be changed during deep peak shaving by designing a first regulating valve group, a first feed water branch, a second feed water branch and a third feed water branch, so that multistage deep peak shaving is realized, different temperature feed water is sent to corresponding parts, the heat absorption capacity of a feed water system in an economizer area is replaced by electric energy, the temperatures of an SCR (selective catalytic reduction) area and an air preheater in low load are ensured to meet the normal operation requirement, and the deep peak shaving capacity of the system is greatly improved; the super-generating capacity of the unit in the electricity price valley period is used for providing energy for the feed water heater to improve the feed water temperature, the steam extraction transformation of the unit is not needed, and the running reliability of the system is ensured.
Additional aspects of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention.
FIG. 1 is a schematic diagram of the overall structure of the system of the present invention.
1, an air preheater; 2. an SCR denitration system; 3. a low-temperature economizer; 4. a high temperature economizer; 5. a drum; 6. a superheater; 7. a steam turbine; 8. a generator; 9. a deaerator; 10. a high pressure heater; 11. a primary feedwater heater; 12. a secondary feedwater heater; 13. a three-stage feedwater heater; 14. an electrical heating control system; 15. a first regulating valve group; 16. the second regulating valve group; 17. the third regulating valve group; 18. a fourth regulating valve group; 19. a water supply main; 20. a first water supply branch; 21. a second water supply branch; 22. and a third water supply branch.
Detailed Description
The invention will be further described with reference to the drawings and examples.
As shown in fig. 1, the boiler feedwater heating system of the deep peak shaver set comprises a steam power generation loop, a first regulating valve group 15, a first feedwater branch 20, a second feedwater branch 21 and a third feedwater branch 22 which are arranged on the steam power generation loop. The steam power generation loop is in the prior art and comprises a deaerator 9, a high-pressure heater 10, a low-temperature economizer 3, a high-temperature economizer 4, a boiler barrel 5, a superheater 6, a steam turbine 7 and a generator 8 which are connected in sequence. The first regulating valve group 15 is arranged on the water supply main 19 between the high-pressure heater 10 and the low-temperature economizer 3. The first water supply branch 20 is connected between the high-pressure heater 10 and the low-temperature economizer 3 and comprises a second regulating valve group 16 and a primary water supply heater 11; the first water feed branch 20 is in parallel relationship with the water feed main 19. The second feedwater branch 21 is connected between the high-pressure heater 10 and the high-temperature economizer 4, and includes a third regulator valve group 17 and a secondary feedwater heater 12. The third water feed branch 22 is connected between the high-pressure heater 10 and the drum 5, and comprises a fourth regulating valve group 18 and a tertiary water feed heater 13. The first regulating valve group 15, the first water supply branch 20, the second water supply branch 21 and the third water supply branch 22 are used for regulating the water supply temperature entering the low-temperature economizer 3, the high-temperature economizer 4 and/or the boiler barrel 5 during deep peak shaving.
The primary feedwater heater 11, the secondary feedwater heater 12 and the tertiary feedwater heater 13 are all in communication and electrically connected with an electric heating control system 14, and controlled by the electric heating control system 14. Meanwhile, the electric heating control system 14 is electrically connected with the generator 8 so as to provide the super-generated energy of the generator 8 for the primary, secondary and tertiary feed water heaters, thereby utilizing the super-generated energy of the system to heat the feed water during peak shaving, improving the energy utilization efficiency and improving the economy of the system.
The number of the second regulating valve groups 16 is 2, and the primary feed water heater 11 is positioned between the 2 second regulating valve groups 16; the number of the third regulating valve groups 17 is 2, and the secondary feedwater heater 12 is positioned between the 2 third regulating valve groups 17; the number of the fourth regulating valve groups 18 is 2, and the three-stage feedwater heater 13 is located between the 2 fourth regulating valve groups 18. The on-off control of the first, second and third water supply branches is realized by controlling the opening and closing of the second, third and fourth regulating valve groups so as to meet different peak regulation demands.
Flow meters are arranged in the low-temperature economizer 3 and the high-temperature economizer 4 and are used for acquiring medium flow in the low-temperature economizer 3 and the high-temperature economizer 4; temperature sensors are arranged at the outlets of the low-temperature economizer 3 and the high-temperature economizer 4 and are used for acquiring the outlet medium temperatures of the low-temperature economizer 3 and the high-temperature economizer 4.
The boiler tail flue is internally provided with a superheater 6, a high-temperature economizer 4, a low-temperature economizer 3, an SCR denitration system 2 and an air preheater 1 in sequence, wherein the air preheater 1 is a rotary air preheater, and temperature sensors are arranged in the SCR denitration system 2 and the air preheater 1 and used for acquiring the flue gas temperature of the SCR denitration system and the air preheater.
In the embodiment, a first regulating valve group 15 is added at a water supply main path 19 between the high-pressure heater 10 and the low-temperature economizer 3, so as to regulate the water supply flow flowing through the water supply main path 19; a first water supply branch 20 (comprising a primary water supply heater 11 and a second regulating valve group 16) is additionally arranged between the high-pressure heater 10 and the low-temperature economizer 3, and can control the water supply to be fed into an inlet of the low-temperature economizer after being heated by the branch; a second water supply branch 21 (comprising a secondary water supply heater 12 and a third regulating valve group 17) is additionally arranged between the high-pressure heater 10 and the high-temperature economizer 4, and part of water supply can be controlled to be fed into an inlet of the high-temperature economizer after being heated by the branch; a third water supply branch 22 (comprising a three-stage water supply heater 13 and a fourth regulating valve group 18) is additionally arranged between the high-pressure heater 10 and the boiler barrel 5, and part of water supply can be controlled to be heated through the branch and then sent into the boiler barrel. An electric heating control system 14 and corresponding power supply and control circuits are additionally arranged between the generator 8 and the first, second and third-stage feed water heaters, the low-valley super-power generation capacity is supplied to the feed water heaters, the power supply quantity of the heaters is regulated according to the steam-water medium temperature at the outlet of the economizer and the flue gas temperature feedback signals of the SCR section and the air preheater section, and the feed water temperature of each branch is controlled.
The working process of deep peak shaving based on the system provided by the invention is as follows:
s0, when the unit normally operates, hot flue gas generated by boiler combustion sequentially passes through the superheater 6, the high-temperature economizer 4, the low-temperature economizer 3, the SCR denitration system 2 and the air preheater 1 in the tail flue and then is discharged out of the boiler. The water supply system is deoxidized by the deoxidizer 9, enters a boiler sequentially through the high-pressure heater 10 and the water supply main path 19, is heated by the low-temperature economizer 3 and the high-temperature economizer 4 sequentially and then is sent to the boiler barrel 5, is evaporated to generate saturated steam, enters the superheater 6 to be heated to generate superheated steam, and enters the steam turbine 7 to apply work to drive the generator 8 to generate electric energy.
S1, in the peak regulation initial stage of the unit, the temperature level of a boiler flue can meet the requirement of stable operation of boiler parts, the feed water is not required to be heated, the first regulating valve group 15 is opened, the second, third and fourth regulating valve groups are closed, and the boiler feed water enters the boiler through the feed water main path 19 according to a normal flow.
S2, as the peak regulation depth of the unit increases, the temperature level of the boiler hearth continuously decreases, so that the temperature in the tail flue decreases. When the temperature is lower than the reaction temperature of the SCR denitration system 2, denitration efficiency is reduced, and the emission of nitrogen oxides of the boiler exceeds the standard; when the temperature of the air preheater 1 is lower than the dew point temperature of ammonium bisulfate, the deposited ash is severely corroded, and the safe and stable operation of equipment is affected. At this time, the first regulating valve group 15 is closed, the second regulating valve group 16 is opened, the third regulating valve group and the fourth regulating valve group are kept closed, the primary feed water heater 11 is put into operation, and the input electric quantity is controlled through the electric heating control system 14 to regulate the feed water temperature. At the moment, boiler feed water is fed into the economizer after being heated by the first feed water branch through the first-stage feed water heater, the feed water temperature is increased, the heat absorption capacity of a medium in smoke is reduced, and the temperature level in a boiler flue is ensured to meet the operation requirement.
And S3, when the peak regulation depth of the unit continues to deepen and the temperature of the medium at the outlet of the high-temperature economizer reaches a protection fixed value, opening the third regulating valve group 17, and keeping the first regulating valve group and the fourth regulating valve group closed to enable the secondary feed water heater 12 to be put into operation. And controlling the flow and the temperature of the medium in the first water supply branch and the second water supply branch through the second regulating valve group, the third regulating valve group and the heater control system. At the moment, part of the water supply of the boiler is directly fed into the high-temperature economizer through the second water supply branch, so that the heat absorption capacity of the part of water supply in the low-temperature economizer is reduced, the flue gas temperature is further improved, and the deep regulating capacity of the unit is deepened.
And S4, when the unit load is further reduced and the medium flow in the low-temperature economizer is low to the design limit, opening the fourth regulating valve group 18, and at the moment, all the second, third and fourth regulating valve groups are opened, wherein the first regulating valve group is kept closed, and the three-stage feed water heater 13 is put into operation. And the medium flow and the temperature in the first, second and third water supply branches are respectively controlled by the second, third and fourth regulating valve groups and the heater control system. At the moment, part of the water supply of the boiler is directly fed into the boiler barrel through the third water supply branch, so that the heat absorption capacity of the part of the water supply in the high-temperature economizer is reduced, the flue gas temperature is increased, the electric heating control system maintains the operation of the existing power supply capacity until the medium flow in the high-temperature economizer reaches the design limit, and the system regulation capacity reaches the limit.
According to the scheme, the unit super-generating capacity during the electricity price valley period is utilized to provide energy for the boiler feed water heater, so that the feed water temperature is increased, the heat absorption capacity of water working media in a flue is reduced, the temperature levels of an SCR denitration zone and an air preheater zone are improved, the problems that flue gas nitrogen oxides exceed standard and the air preheater is seriously blocked when the boiler runs under low load are solved, and the unit deep regulating capacity is improved. The system utilizes the online electric quantity in the electricity price valley period, reduces the power generation loss and has better economic benefit. In addition, the system sets multi-stage water supply heating according to peak regulation depth requirements, can supply water with different temperatures to corresponding components, replaces the heat absorption capacity of the water supply system in the economizer region with electric energy, and ensures that the temperature of the SCR region and the air preheater meet normal operation requirements during low load.
Compared with the existing No. 0 high-heating scheme, the system-independent electric heating equipment can effectively solve the heat source problem under the condition of not influencing the original system, ensures the flue temperature under smaller boiler load through multistage heating, can be basically applied to all thermal power units with deep peak regulation requirements, and has wider application range; in addition, the system utilizes electric energy to heat the water supply, so that the utilization of high-parameter steam is avoided, the system is simpler, and the equipment and transformation cost is reduced; the temperature rise effect of boiler feed water can be flexibly controlled by the electric heating controller, and the depth peak regulation effect and the system safety are more reliable.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The boiler water supply heating system of the deep peak shaver set is characterized by comprising a steam power generation loop, a first regulating valve group, a first water supply branch, a second water supply branch and a third water supply branch, wherein the first regulating valve group, the first water supply branch, the second water supply branch and the third water supply branch are arranged on the steam power generation loop; the steam power generation loop comprises a deaerator, a high-pressure heater, a low-temperature economizer, a high-temperature economizer, a boiler barrel, a superheater, a steam turbine and a generator which are connected in sequence; the first regulating valve group is arranged between the high-pressure heater and the low-temperature economizer; the first water supply branch is connected between the high-pressure heater and the low-temperature economizer and comprises a second regulating valve group and a primary water supply heater; the second water supply branch is connected between the high-pressure heater and the high-temperature economizer and comprises a third regulating valve group and a secondary water supply heater; the third water supply branch is connected between the high-pressure heater and the boiler barrel and comprises a fourth regulating valve group and a three-stage water supply heater; the first regulating valve group, the first water supply branch, the second water supply branch and the third water supply branch are used for regulating the water supply temperature entering the low-temperature economizer, the high-temperature economizer and/or the boiler barrel during deep peak shaving.
2. The depth peaking unit boiler feedwater heating system of claim 1, further comprising an electrical heating control system coupled to the primary feedwater heater, the secondary feedwater heater, and the tertiary feedwater heater and electrically coupled to the electrical power generator.
3. The boiler feedwater heating system of a depth peaking unit of claim 1, wherein the number of second regulating valve groups is 2, and the primary feedwater heater is located between 2 second regulating valve groups; the number of the third regulating valve groups is 2, and the secondary feedwater heater is positioned between the 2 third regulating valve groups; the number of the fourth regulating valve groups is 2, and the three-stage feed water heater is positioned between the 2 fourth regulating valve groups.
4. The boiler feed water heating system of a deep peak shaver set according to claim 1, further comprising an SCR denitration system and an air preheater, wherein the superheater, the high-temperature economizer, the low-temperature economizer, the SCR denitration system and the air preheater are all arranged in a boiler tail flue.
5. The boiler feed water heating system of a deep peak shaver set according to claim 4, wherein temperature sensors are arranged in the SCR denitration system and the air preheater for acquiring flue gas temperatures at the SCR denitration system and the air preheater.
6. The boiler feed water heating system of a deep peak shaver set according to claim 1, wherein the low-temperature economizer and the high-temperature economizer are internally provided with flow meters for obtaining medium flow in the low-temperature economizer and the high-temperature economizer; and the outlets of the low-temperature economizer and the high-temperature economizer are respectively provided with a temperature sensor for acquiring the outlet medium temperature of the low-temperature economizer and the high-temperature economizer.
7. A method for heating boiler feed water of a depth peak shaver set, which is characterized in that the boiler feed water heating system of the depth peak shaver set provided by any one of claims 1 to 6 comprises:
s1, when the system operates normally, a first regulating valve group is opened, a second regulating valve group, a third regulating valve group and a fourth regulating valve group are closed, and boiler feed water enters the boiler through a water supply main path;
s2, when the temperature of the flue gas does not meet the temperature requirements of an SCR denitration system and/or a rotary air preheater, closing a first regulating valve group, opening a second regulating valve group, and heating boiler feed water by using a primary feed water heater;
s3, when the temperature of the medium at the outlet of the high-temperature economizer reaches a protection fixed value, opening a third regulating valve group, and heating part of boiler feed water through a secondary feed water heater and then feeding the part of boiler feed water into the high-temperature economizer;
and S4, when the medium flow in the low-temperature economizer is reduced to the design limit, opening a fourth regulating valve group, and heating part of boiler feed water through the three-stage feed water heater and then feeding the heated boiler feed water into the boiler barrel.
8. A depth peaking unit boiler feedwater heating method of claim 7, wherein the super power generation of the generator is used to power the primary feedwater heater, the secondary feedwater heater, and/or the tertiary feedwater heater.
9. The method for heating boiler feed water of deep peak shaver set according to claim 7, wherein in step S3, the heat absorption capacity of boiler feed water in the low-temperature economizer is reduced by controlling the opening degree of the second regulating valve group and/or the third regulating valve group and the heating capacity of the primary feed water heater and/or the secondary feed water heater and controlling the medium flow and the temperature in the first feed water branch and the second feed water branch.
10. The method for heating boiler feed water of deep peak shaver set according to claim 7, wherein in step S4, the heat absorption capacity of boiler feed water in the high-temperature economizer is reduced by controlling the opening degree of the second regulating valve group, the third regulating valve group and the fourth regulating valve group, and the heating capacity of the primary feed water heater, the secondary feed water heater and the third feed water heater.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311717856.6A CN117490044A (en) | 2023-12-13 | 2023-12-13 | Boiler feed water heating system and method for deep peak shaving unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311717856.6A CN117490044A (en) | 2023-12-13 | 2023-12-13 | Boiler feed water heating system and method for deep peak shaving unit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117490044A true CN117490044A (en) | 2024-02-02 |
Family
ID=89676615
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311717856.6A Pending CN117490044A (en) | 2023-12-13 | 2023-12-13 | Boiler feed water heating system and method for deep peak shaving unit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117490044A (en) |
-
2023
- 2023-12-13 CN CN202311717856.6A patent/CN117490044A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4572110A (en) | Combined heat recovery and emission control system | |
| KR102305811B1 (en) | Steam power generation plant, method for modifying steam power generation plant and method for operating steam power generation | |
| CN111852597A (en) | Variable-parameter multi-element cascade thermoelectric decoupling system of thermal power heat supply unit and adjusting method | |
| CN111649349A (en) | Full-load denitration system for deep peak shaving of boiler and operation method thereof | |
| CN114909193B (en) | Thermal power generating unit flexible operation system based on fused salt heat storage | |
| CN210035651U (en) | High-parameter heat supply system of steam turbine | |
| CN113154356A (en) | High-temperature steam composite thermodynamic system and utilization method thereof | |
| CN212296519U (en) | Variable-parameter multi-element cascade thermoelectric decoupling system of thermal power heat supply unit | |
| CN113431651A (en) | Low-load operation system with one furnace and two machines | |
| CN112303604A (en) | Economizer temperature governing system that unit start-up process denitration was put into | |
| EP3232022B1 (en) | System and method for improving the performance of a heat recovery steam generator | |
| CN212511221U (en) | Full-load denitration device for deep peak shaving of boiler | |
| CN215259733U (en) | Dry-wet state undisturbed switching system suitable for supercritical unit under deep peak regulation state | |
| CN117490044A (en) | Boiler feed water heating system and method for deep peak shaving unit | |
| CN108487955A (en) | System and method is utilized based on the coal gas synergy that steam parameter is promoted | |
| CN200993031Y (en) | Residual heat power generating system with adjustable flash system | |
| CN112082147A (en) | Low-pressure superheater system of waste heat boiler | |
| CN101201159B (en) | Method and system for generating power by waste heat with adjustable flash evaporation system | |
| CN206094020U (en) | Improve device of boiler feed water temperature | |
| CN214948970U (en) | High-temperature steam composite thermodynamic system | |
| CN219034829U (en) | Combined operation system of gas boiler generator set and sintering waste heat generator set | |
| CN211011382U (en) | Waste incineration power generation bypass recovery system | |
| CN114576605B (en) | System and method for realizing deep peak shaving by heating water supply through reheat steam | |
| CN217584405U (en) | Concurrent heating formula thermal power generating unit and electric wire netting | |
| CN216203242U (en) | System for improving low-load feed water temperature of power station boiler |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |