CN111678117A - Exhaust smoke waste heat recovery system of 1000MW secondary reheating power plant - Google Patents
Exhaust smoke waste heat recovery system of 1000MW secondary reheating power plant Download PDFInfo
- Publication number
- CN111678117A CN111678117A CN202010447056.7A CN202010447056A CN111678117A CN 111678117 A CN111678117 A CN 111678117A CN 202010447056 A CN202010447056 A CN 202010447056A CN 111678117 A CN111678117 A CN 111678117A
- Authority
- CN
- China
- Prior art keywords
- low
- temperature
- bypass
- waste heat
- air preheater
- 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
Images
Classifications
-
- 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
- F22D1/36—Water and air preheating systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES
- F23J3/00—Removing solid residues from passages or chambers beyond the fire, e.g. from flues by soot blowers
- F23J3/02—Cleaning furnace tubes; Cleaning flues or chimneys
Abstract
The invention relates to a 1000MW secondary reheating power plant exhaust smoke waste heat recovery system, which comprises a smoke bypass arranged on an air preheater of a boiler, wherein a bypass primary high-temperature heater and a bypass secondary low-temperature heater are arranged on the smoke bypass, the bypass primary high-temperature heater is used for heating high-pressure feed water at an outlet of a steam turbine feed pump, and the bypass secondary low-temperature heater is used for heating condensed water; the boiler air preheater outlet tail flue dust remover inlet end is provided with low temperature low pressure economizer, low temperature low pressure economizer is used for heating air preheater entry cold wind through the circulating water. The invention utilizes the waste heat of the boiler exhaust smoke to heat the condensed water, the cold air and the feed water simultaneously, improves the low-temperature smoke energy level, greatly improves the waste heat utilization efficiency, further reduces the standard coal consumption of the unit, achieves the purposes of energy conservation and emission reduction, and simultaneously improves the heat economy of the unit.
Description
Technical Field
The invention belongs to the technical field of thermal power generation, and particularly relates to a 1000MW secondary reheating power plant exhaust smoke waste heat recovery system.
Background
Along with the rapid development of the economy of China, the power demand is increased year by year, more and more large coal-fired thermal generator sets are put into use, and the supply of coal resources is tense day by year, so that the efforts of improving the power generation efficiency of the generator sets and reasonably and effectively utilizing the limited coal resources are very important while ensuring the smooth production and power generation of the generator sets.
The utility boiler is the equipment with the largest energy consumption of the power plant and is also the source of a series of energy consumption processes of the power plant. In order to generate motive power for power generation to drive steam and ensure larger power-applying capacity, a power station boiler consumes a large amount of coal resources.
For utility boilers, the boiler flue gas loss is the largest one of the boiler heat losses, accounting for about 70% to 80% of the boiler heat loss. Calculation shows that the boiler efficiency is reduced by 1% when the exhaust gas temperature of the boiler of the thermal power generating unit rises by 15-20 ℃, and the standard coal consumption is increased by 3-4 g/kWh. The exhaust gas temperature of the boiler is too high, which causes an increase in the coal consumption of the thermal power plant. Therefore, the exhaust gas temperature of the power station boiler is reduced, the exhaust gas waste heat of the power station boiler is effectively utilized, coal consumption can be greatly saved, energy is saved, carbon emission is greatly reduced, the national energy-saving and emission-reducing policy is met, and the economic benefit and the social benefit are huge.
The existing flue gas waste heat utilization scheme of the power plant at present mainly comprises the steps that low-temperature coal economizers are arranged at the inlet of a dust remover of a flue at the tail of a boiler and the outlet of an induced draft fan, the exhaust temperature of the boiler is generally about 140 ℃ at the highest for lignite and about 125 ℃ for bituminous coal, the recovered flue gas waste heat generally replaces the last several levels of low-pressure steam extraction of a regenerative system of a steam turbine, the standard coal consumption of a unit capable of being reduced is about 1-2 g/kw.h, and the energy level of flue gas waste heat utilization is low. Therefore, a high-energy-level low-temperature economizer scheme is needed to reduce the heat loss of the exhaust smoke, improve the heat economy of the unit and maximally utilize the waste heat of the exhaust smoke.
Disclosure of Invention
The invention aims to provide a 1000MW secondary reheating power plant exhaust smoke waste heat recovery system to reduce exhaust smoke heat loss, improve the heat economy of a unit and maximally utilize the exhaust smoke waste heat.
The invention provides a 1000MW secondary reheating power plant exhaust smoke waste heat recovery system, which comprises a smoke bypass arranged on a boiler air preheater, wherein a bypass primary high-temperature heater and a bypass secondary low-temperature heater are arranged on the smoke bypass, the bypass primary high-temperature heater is used for heating high-pressure feed water at an outlet of a steam turbine feed pump, and the bypass secondary low-temperature heater is used for heating condensed water;
the boiler air preheater outlet tail flue dust remover inlet end is provided with low temperature low pressure economizer, low temperature low pressure economizer is used for heating air preheater entry cold wind through the circulating water.
Further, the bypass secondary low-temperature heater is connected with the dust remover, and the dust remover is connected with the low-temperature low-pressure economizer through an induced draft fan.
Further, the low-temperature and low-pressure economizer is connected with a preposed air preheater, and the preposed air preheater is connected with a primary fan and a secondary fan.
Further, the cold end material of the low-temperature and low-pressure economizer is ND steel or Corton steel.
Furthermore, a soot blower is arranged on the heat transfer surface of the low-temperature low-pressure economizer.
Further, the soot blower is a sound wave soot blower or a long telescopic steam soot blower.
By means of the scheme, the exhaust smoke waste heat recovery system of the 1000MW double-reheat power plant utilizes the exhaust smoke waste heat of the boiler to heat the condensed water, the cold air and the feed water at the same time, the low-temperature smoke energy level is improved, the waste heat utilization efficiency is greatly improved, the standard coal consumption of the unit is further reduced, the purposes of energy conservation and emission reduction are achieved, and the heat economy of the unit is improved at the same time.
The foregoing is a summary of the present invention, and in order to provide a clear understanding of the technical means of the present invention and to be implemented in accordance with the present specification, the following is a detailed description of the preferred embodiments of the present invention.
Drawings
FIG. 1 is a schematic structural diagram of a flue gas waste heat recovery system of a 1000MW double reheat power plant.
Reference numerals in the figures;
1-bypassing a first-stage high-temperature heater; 2-bypassing the secondary low temperature heater; 3-low temperature and low pressure economizer; 4-preposition air preheater; 5-a primary air fan; 6-a secondary fan; 7-a dust remover; 8-induced draft fan.
Detailed Description
The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
Referring to fig. 1, the embodiment provides a flue gas waste heat recovery system of a 1000MW secondary reheating power plant, which includes a flue gas bypass arranged on an air preheater of a boiler, a bypass primary high-temperature heater 1 and a bypass secondary low-temperature heater 2 are arranged on the flue gas bypass, the bypass primary high-temperature heater 1 is used for heating high-pressure feed water at an outlet of a steam turbine feed pump, and the bypass secondary low-temperature heater 2 is used for heating condensed water;
the inlet end of a flue dust remover 7 at the tail part of the outlet of the boiler air preheater is provided with a low-temperature low-pressure economizer 3, and the low-temperature low-pressure economizer 3 is used for heating cold air at the inlet of the air preheater through circulating water.
In this embodiment, bypass second grade low temperature heating ware with the dust remover is connected, the dust remover pass through the draught fan with low temperature low pressure economizer connects.
In the present embodiment, the low-temperature and low-pressure economizer 3 is connected to the pre-air preheater 4, and the primary air blower 5 and the secondary air blower 6 are connected to the pre-air preheater 4.
In the embodiment, the cold end material of the low-temperature low-pressure economizer 3 adopts ND steel or Corton steel.
In the present embodiment, soot blowers are installed on the heat transfer surface of the low-temperature and low-pressure economizer 3.
In the present embodiment, the sootblowers are acoustic sootblowers or long telescopic steam sootblowers.
The preposed air preheater heats cold air by using the waste heat of the boiler flue gas, so that the temperature of the air at the inlet of the air preheater is increased, the heat transfer temperature difference of the air preheater is reduced, the heat transfer capacity of the air preheater is reduced, the hot air temperature is increased, the temperature of the exhaust gas is increased, only the preposed air preheater device exists, most of the used waste heat of the boiler flue gas is useless, and the waste heat is exhausted from the flue gas side of the air preheater. This embodiment reduces the flue gas volume through the air preheater through setting up the flue gas bypass, can get off too high hot-blast temperature drop, and air preheater export gas temperature drops to former smoke exhaust temperature, is used for condensate and feedwater with bypass gas heat, and the gas temperature also drops to former smoke exhaust temperature. Because this part flue gas that the bypass flowed out is far than the exhaust gas temperature of traditional meaning, so the exit temperature of its heated condensate water and feedwater will be improved by a wide margin, can cross high and add directly and get into the economizer, passes through the energy level with the low energy level heat and promotes for flue gas waste heat has obtained the deep utilization under the high energy level.
In the embodiment, 6 low-temperature low-pressure economizers are arranged at the front bell mouth inlet of the dust remover 7, the low-temperature low-pressure economizer can partially replace an airflow uniform distribution device at the inlet of the dust remover, the floor area can be saved, the coal consumption of a unit can be saved, and the maximum economic benefit of the operation of the dust remover 7 can be realized; because the temperature of the smoke at the inlet of the dust remover is reduced, the dust removal efficiency is improved. In addition, the low-temperature low-pressure economizer 3 is arranged at the inlet end of the dust remover 7, the volume flow of the flue gas at the downstream of the dust remover is reduced by about 13 percent, so the capacities of a flue, an induced draft fan and the like can be correspondingly reduced, and the service power is reduced. The high-pressure feed water and the condensed water are heated by recycling the waste heat of the flue gas, so that the steam extraction flow of each stage of the steam turbine regenerative system is reduced, the steam inlet quantity of the steam turbine is reduced, the heat consumption of the unit is reduced, and the aim of saving energy is fulfilled.
In the embodiment, the bypass first-stage high-temperature heater 1 heats the high-pressure feed water of the steam turbine to reduce the smoke temperature from 365 ℃ to 202 ℃, the bypass second-stage high-temperature heater 2 heats the condensed water to reduce the smoke temperature from 202 ℃ to 123 ℃, and the smoke of the smoke bypass is mixed with the main smoke of the air preheater and then is finally 115 ℃;
the low-temperature low-pressure economizer 3 reduces the temperature of the flue gas from 115 ℃ to 90 ℃, utilizes circulating water to heat cold air at an inlet of the air preheater, heats the cold air at the inlet of the air preheater to 60 ℃ and then enters the air preheater to balance the heat extracted by a flue gas bypass of the air preheater, and the thermodynamic balance of the air preheater is basically the same as that of the air preheater without the air preheater bypass, so that the boiler efficiency is basically maintained unchanged.
The rated design inlet water temperature of the low-temperature low-pressure economizer of the embodiment is 75 ℃, the cold end smoke temperature is 90 ℃, the design value of the cold end metal wall temperature is set to be 85 ℃, the design value of the cold end metal wall temperature is higher than the dew point temperature of smoke water by about 42 ℃ and the difference between the cold end metal wall temperature and the dew point temperature of water vapor is higher than 30 ℃ by taking the factors such as the heat transfer coefficient of an H-shaped fin tube of the low-temperature low-pressure economizer and the like into consideration, and a certain allowance is. In the embodiment, the minimum value of the metal wall temperature of the heat transfer pipe of the low-temperature low-pressure economizer 3 is controlled to be more than 65 ℃, the water inlet temperature is controlled to be not less than 60 ℃, and the service life of the equipment can be ensured to be more than 10 years.
In the embodiment, under the full-load working condition of the unit, the exhaust gas temperature is higher, and the temperature of the metal pipe wall of the heat transfer pipe of the low-temperature low-pressure economizer 3 is controlled to be not less than 80 ℃; when the unit operates under a low load, the exhaust gas temperature is low, and the high-temperature water at the outlet of the low-temperature low-pressure economizer 3 is recycled to the inlet of the low-temperature low-pressure economizer to mix water, so that the temperature of the metal pipe wall of the heat transfer pipe is not lower than 65 ℃ in operation.
The low-temperature low-pressure economizer is an energy-saving device for recovering waste heat of boiler exhaust gas, and when the economizer operates, the temperature of the flue gas and the temperature of the inlet water are lower, the flue gas is easy to dewfall, and the hidden danger of low-temperature corrosion exists, so that the heat transfer pipe needs to be specially treated, the corrosion resistance of the surface of the heat transfer pipe is improved, and the influence of the low-temperature corrosion on the whole equipment is reduced.
The cold end material of the low-temperature and low-pressure economizer in the embodiment is ND steel or Corton steel, and under the condition that the cold end metal wall temperature is higher than or equal to 70 ℃, when the wall thickness of the heat transfer pipe reasonably considers the corrosion allowance, the service life of the heat transfer pipe can be guaranteed to be not less than 10 years, and the service life of the shell and other heat transfer pipes is more than 30 years.
The ash in the boiler flue gas can not only pollute the surface of a heat transfer pipe and influence the heat transfer efficiency, but also block a flue gas flow channel in serious conditions, increase the flow resistance of the flue gas, even influence the safe operation and need to be stopped for ash removal. In the embodiment, the low-temperature low-pressure economizer is arranged at the front end of an inlet horn of the dust remover, the ash deposited on the heat transfer pipe is removed by utilizing the scouring action of smoke dust, and the smoke velocity passing through the heat transfer surface is controlled within the range of 7-10 m/s to avoid abrasion; the heat transfer surface is additionally provided with a sound wave or long telescopic steam soot blower, and when the system runs, the soot is normally blown by the soot blower without being washed by water; when the heat transfer device is stopped, the high-pressure water gun is used for flushing in situ through manual operation according to the dust deposition condition of the heat transfer pipe.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, it should be noted that, for those skilled in the art, many modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.
Claims (6)
1. The flue gas waste heat recovery system of the 1000MW double-reheat power plant is characterized by comprising a flue gas bypass arranged on an air preheater of a boiler, wherein a bypass primary high-temperature heater and a bypass secondary low-temperature heater are arranged on the flue gas bypass, the bypass primary high-temperature heater is used for heating high-pressure feed water at an outlet of a steam turbine feed pump, and the bypass secondary low-temperature heater is used for heating condensed water;
the boiler air preheater outlet tail flue dust remover inlet end is provided with low temperature low pressure economizer, low temperature low pressure economizer is used for heating air preheater entry cold wind through the circulating water.
2. The exhaust smoke waste heat recovery system of 1000MW double reheat power plant of claim 1, wherein the bypass secondary low temperature heater is connected with the dust remover, and the dust remover is connected with the low temperature low pressure economizer through an induced draft fan.
3. The 1000MW double reheat power plant exhaust smoke waste heat recovery system of claim 2, wherein the low temperature low pressure economizer is connected with a pre-air preheater, and the pre-air preheater is connected with a primary fan and a secondary fan.
4. The exhaust smoke waste heat recovery system of 1000MW double reheat power plant of claim 1, wherein the cold end material of the low temperature and low pressure economizer is ND steel or Coryton steel.
5. The 1000MW double reheat power plant flue gas waste heat recovery system of claim 1, wherein the low temperature low pressure economizer heat transfer surface is fitted with a soot blower.
6. The 1000MW double reheat power plant flue gas waste heat recovery system of claim 5, wherein the soot blower is a sonic soot blower or a long telescopic steam soot blower.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010447056.7A CN111678117A (en) | 2020-05-25 | 2020-05-25 | Exhaust smoke waste heat recovery system of 1000MW secondary reheating power plant |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010447056.7A CN111678117A (en) | 2020-05-25 | 2020-05-25 | Exhaust smoke waste heat recovery system of 1000MW secondary reheating power plant |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111678117A true CN111678117A (en) | 2020-09-18 |
Family
ID=72434413
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010447056.7A Pending CN111678117A (en) | 2020-05-25 | 2020-05-25 | Exhaust smoke waste heat recovery system of 1000MW secondary reheating power plant |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111678117A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113803706A (en) * | 2021-09-23 | 2021-12-17 | 上海理工大学 | Power generation system based on hot air recycling utilizes boiler afterbody flue gas waste heat |
| CN113803706B (en) * | 2021-09-23 | 2024-04-19 | 上海理工大学 | Power generation system based on hot air recycling and utilizing waste heat of tail flue gas of boiler |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102607011A (en) * | 2012-03-22 | 2012-07-25 | 济南达能动力技术有限责任公司 | Multi-stage utilization system for transferring exhaust afterheat energy of power station boiler |
| CN206320726U (en) * | 2016-12-16 | 2017-07-11 | 东方电气集团东方锅炉股份有限公司 | A kind of thermal power plant's tail flue gas afterheat utilizing system coupled based on machine stove depth |
| CN108443906A (en) * | 2018-05-08 | 2018-08-24 | 山东电力工程咨询院有限公司 | Smoke waste heat utilization system and method based on multiple level with recycling heating cold wind |
| CN210197332U (en) * | 2019-05-23 | 2020-03-27 | 中国电力工程顾问集团东北电力设计院有限公司 | Cascade utilization deep coupling system for smoke, wind and sewage waste heat of coal-fired boiler |
-
2020
- 2020-05-25 CN CN202010447056.7A patent/CN111678117A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102607011A (en) * | 2012-03-22 | 2012-07-25 | 济南达能动力技术有限责任公司 | Multi-stage utilization system for transferring exhaust afterheat energy of power station boiler |
| CN206320726U (en) * | 2016-12-16 | 2017-07-11 | 东方电气集团东方锅炉股份有限公司 | A kind of thermal power plant's tail flue gas afterheat utilizing system coupled based on machine stove depth |
| CN108443906A (en) * | 2018-05-08 | 2018-08-24 | 山东电力工程咨询院有限公司 | Smoke waste heat utilization system and method based on multiple level with recycling heating cold wind |
| CN210197332U (en) * | 2019-05-23 | 2020-03-27 | 中国电力工程顾问集团东北电力设计院有限公司 | Cascade utilization deep coupling system for smoke, wind and sewage waste heat of coal-fired boiler |
Non-Patent Citations (1)
| Title |
|---|
| 胡荫平: "《电站锅炉手册》", 30 April 2005, 中国电力出版社 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113803706A (en) * | 2021-09-23 | 2021-12-17 | 上海理工大学 | Power generation system based on hot air recycling utilizes boiler afterbody flue gas waste heat |
| CN113803706B (en) * | 2021-09-23 | 2024-04-19 | 上海理工大学 | Power generation system based on hot air recycling and utilizing waste heat of tail flue gas of boiler |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2018014768A1 (en) | Residual heat reuse system for turbine-boiler integrated heat energy circulation | |
| CN101245400B (en) | Recycling of coal gas of steel-smelting revolving furnace with dry method and sensible heat power generation system | |
| CN201852474U (en) | Combined recovery and power generation system for waste heat in flue gas of sintering machine and waste gas of cooling machine | |
| CN105889897B (en) | A kind of thermal power plant residual heat integrative recycling system and method | |
| CN101392992A (en) | Silicon smelting electric furnace waste heat power generation process flow and configuration | |
| CN105157010A (en) | Coal-fired power generation system based on bypass flue at tail part of boiler | |
| CN109668165A (en) | Hot Secondary Air and smoke waste heat utilization system and thermal power generation unit | |
| CN205383589U (en) | Novel energy -efficient application system of afterbody flue gas heat energy set | |
| CN202915334U (en) | Multilevel utilization system for exhausted smoke waste heat energy transfer of utility boiler | |
| CN203771380U (en) | Condensation waste heat recovery steam boiler | |
| CN105402761A (en) | Deep coupling utilization system for turbine steam exhaust waste heat and boiler flue gas waste heat | |
| CN201103915Y (en) | Desulfurized flue gas waste heat recovery system for fire coal generator set | |
| CN110986031B (en) | System for avoiding water vapor condensation in gas boiler flue gas recirculation pipeline | |
| CN205690425U (en) | A kind of residual heat from boiler fume Multi-class propagation combines condensation water heating supply air system | |
| CN102305394A (en) | Coking furnace flue-gas waste-heat boiler | |
| CN208124270U (en) | A kind of gas cooler and fume afterheat providing warm air device association system | |
| CN110094750A (en) | A kind of coal unit low-temperature flue gas waste heat depth recycling gradient utilization system and method | |
| CN102494329A (en) | Device for utilizing flue gas waste heat of boiler comprehensively | |
| CN111678117A (en) | Exhaust smoke waste heat recovery system of 1000MW secondary reheating power plant | |
| CN209495348U (en) | Hot Secondary Air and smoke waste heat utilization system and thermal power generation unit | |
| CN111678116A (en) | Gradient utilization method for flue gas of 1000MW double reheating power plant | |
| CN208620383U (en) | Residual heat of air compressor recycling equipment | |
| CN205782834U (en) | A kind of residual heat from boiler fume utilizes combining heating system | |
| CN205535923U (en) | Cleaning type coal fired boiler discharges fume waste heat and puies forward matter and utilize system | |
| CN205208615U (en) | Multistage system that utilizes of waste heat of boiler flue gas |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200918 |