CN103196134A - Natural-circulation drum boiler with flue heating system - Google Patents
Natural-circulation drum boiler with flue heating system Download PDFInfo
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- CN103196134A CN103196134A CN 201310128408 CN201310128408A CN103196134A CN 103196134 A CN103196134 A CN 103196134A CN 201310128408 CN201310128408 CN 201310128408 CN 201310128408 A CN201310128408 A CN 201310128408A CN 103196134 A CN103196134 A CN 103196134A
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Abstract
The invention discloses a natural-circulation drum boiler with a flue heating system. The natural-circulation drum boiler comprises a boiler, a drum, a coal economizer, an SCR (selective catalytic reduction) reactor, an air pre-heater and the flue heating system. The flue heating system comprises a water pump, a switch valve and an electric adjusting valve, a downcomer of the drum is connected with a water feed bag of the boiler, the water feed bag of the boiler is connected with an inlet pipeline of the water pump through the switch valve, and an outlet pipeline of the water pump is connected with a water feed inlet pipeline of the coal economizer through the electric adjusting valve. The natural-circulation drum boiler with the flue heating system is applicable to subcritical and ultrahigh-pressure forced-circulation drum boilers, allows the SCR reactor to normally operate under the condition of low load and/or low atmospheric temperature, and guarantees that flue discharge quality of the subcritical and ultrahigh-pressure forced-circulation drum boilers can reach national standards under the conditions of low load and/or atmospheric temperature.
Description
Technical field
The present invention relates to a kind of Natural Circulation dum boiler that has the flue gas temperature elevation system, improve the SCR reactor inlet cigarette temperature of former Natural Circulation dum boiler by the operation of flue gas temperature elevation system, needs improve the needs of flue-gas temperature when causing under boiler at low load and/or the atmospheric temperature low condition to satisfy that SCR reactor inlet flue-gas temperature is low can't to come into operation Natural Circulation dum boiler denitrating system.
Background technology
The energy resource structure of China is based on coal, and the coal consumption amount is also with sustainable growth.According to statistics, China's capacity of installed generator moderate heat Denso machine capacity accounts for more than 74% at present, and in a very long time in future, the coal-fired nitrogen oxides pollution that causes is the another important environmental problem after sulfur dioxide pollution." thermal power plant's atmosphere pollutants emission standards (GB13223-2011) " that implements in January, 2011 is reduced to 100 ~ 200mg/m to the highest permission concentration of emission of station boiler nitrogen oxide limit value simultaneously
3, coal-fired electric generation furnace configuration SCR reactor realizes that denitrating flue gas has become a kind of standard configuration.Along with development economic and society, will be strict gradually to the concentration of emission of SCR reactor denitrification apparatus and the rate requirement that comes into operation.
Nitrogen oxide refers generally to NO, NO
2, NO
3, N
2O, N
2O
3Deng, be referred to as NO
xThe nitrogen oxide that generates in the boiler combustion process (is mainly NO and NO
2) seriously polluted environment.Therefore suppress NO
xGeneration and remove the NO that in flue gas, has generated
xOne of subject matter that oneself must consider when becoming boiler combustion design and operation.
Selective catalytic reduction (SCR) is most widely used, and the denitration method for flue gas of technology maturation, and oneself becomes the mainstream technology of present station boiler denitration.SCR denitration efficiency height, concentration of emission is low can be satisfied at present and the environmental requirement of strictness from now on, is subjected to China and the attention of other country in the world day by day.
Present commercial SCR reactor denitration temperature is more widely generally controlled at 320 ~ 400 ℃.When the temperature of SCR reactor inlet flue gas is lower than 300 ℃, the activity of SCR catalyst reactor is reduced, can't realize the normal operation of SCR reactor denitration.Therefore, the temperature that guarantees suitable SCR reactor denitration inlet flue gas is the key of the normal operation of SCR reactor denitration.
Present reason owing to Natural Circulation dum boiler design aspect, when the Natural Circulation dum boiler moves under underload and/or atmospheric temperature low condition, the SCR reactor smoke inlet temperature of the Natural Circulation dum boiler of subcritical and super-pressure differs with the temperature that can guarantee the normal operation of SCR reactor and can reach more than 20 ℃, therefore under underload and/or atmospheric temperature low condition, the SCR reactor can't put into operation, and smoke emissioning concentration can not satisfy national requirements for environmental protection.
Summary of the invention
The objective of the invention is provides a kind of Natural Circulation dum boiler that has the flue gas temperature elevation system in order to solve the Natural Circulation dum boiler technical problem that the SCR reactor can't put into operation under underload and/or atmospheric temperature low condition.Namely by the water system of existing natural circulation dum boiler is transformed, the high temperature saturation water that utilizes water pump will be entered the following water bag of boiler by the down-comer of drum is delivered to the side-entrance of boiler economizer water to be mixed with the economizer feedwater, to improve the feed temperature of economizer, and then improve the boiler economizer exit gas temperature, make it temperature and reach the Applicable temperature that the SCR reactor puts into operation.The present invention is applicable to subcritical and Natural Circulation dum boiler super-pressure.
Know-why of the present invention
The flow process of former boiler water side is that feedwater enters drum after heating up through economizer.The saturation water of the bottom of drum enters the Xia Shuibao of boiler through down-comer, and the water of following water bag is by the water-cooling wall draw heat that rises, thereby part is evaporated to steam, and steam water interface enters drum and finishes carbonated drink separation.Saturated vapor after the separation enters superheater, and saturation water then enters down-comer and continues circulation.
Transforming increases, the saturation water that can realize the drum bottom enters economizer behind the following water bag of boiler, the feedwater of this part saturation water and economizer mixes, improve economizer entrance feed temperature, thereby the temperature difference of water and flue gas in the minimizing economizer, the flue gas thermal discharge is reduced, the temperature of economizer exit flue gas is improved, the entrance flue gas temperature that enters the SCR reactor also raises, the saturated water amount that enters the economizer entrance by adjusting is adjusted the temperature that the economizer entrance feeds water, the flue-gas temperature of the step of going forward side by side joint SCR reactor inlet makes it to reach the put into operation temperature of required flue gas of SCR reactor.
Technical scheme of the present invention
A kind of Natural Circulation dum boiler that has the flue gas temperature elevation system comprises boiler, drum, economizer, SCR reactor, air preheater, also comprises the flue gas temperature elevation system;
Described flue gas temperature elevation system comprises water pump, switch valve, electric control valve;
The down-comer of described drum is connected with the following water bag of boiler, and the following water Bao Zaijing switch valve of boiler is connected with the pump entrance pipeline, and the outlet conduit of water pump is in parallel with the feed-water intake pipeline of economizer behind electric control valve.
In a preferred embodiment of the present invention, between the outlet of water pump and electric control valve, check-valves is installed, thereby is avoided entering the aqueous reflux in the economizer, thereby guarantee the safe operation in boiler of flue gas temperature elevation system.
The operation principle of above-mentioned a kind of Natural Circulation dum boiler that has a flue gas temperature elevation system is as follows:
The schematic flow sheet of former boiler water side enters drum after feedwater process economizer heats up as shown in Figure 1.The saturation water process down-comer of drum bottom enters the Xia Shuibao of boiler, and again by water-cooling wall rising draw heat, thereby part is evaporated to steam, and steam water interface enters drum and finishes carbonated drink separation.Saturated vapor after the separation enters superheater, and saturation water then enters down-comer and continues circulation.
Have the flue gas temperature elevation system dum boiler the water side schematic flow sheet as shown in Figure 2, the saturation water of drum bottom i.e. isolating door 1 among the figure of switch valve successively behind the following water bag of boiler, water pump, electric control valve i.e. adjustment doors among the figure 3 is regulated and is entered economizer, enter the mixing of the feedwater of this part saturation water of economizer and economizer, improve the temperature of economizer entrance feedwater, thereby reduced the temperature difference of water and flue gas in the economizer, cause the minimizing of flue gas thermal discharge, the temperature of economizer exit flue gas has had raising to a certain degree, thereby makes the temperature of the flue gas that enters the SCR reactor can satisfy the Applicable temperature that the SCR reactor puts into operation.
A kind of Natural Circulation dum boiler that has the flue gas temperature elevation system of the present invention is applicable to subcritical and dum boiler super-pressure.
Beneficial effect of the present invention
A kind of Natural Circulation dum boiler that has the flue gas temperature elevation system of the present invention, by increasing water pump, switch valve, electric control valve and corresponding pipeline, to behind the following water bag of boiler, mix with the feedwater that enters economizer from the fractional saturation water that drum is discharged, thereby improved the temperature of economizer entrance feedwater, reduced the temperature difference of water and flue gas in the economizer, make the minimizing of flue gas thermal discharge, make the temperature of economizer exit flue gas improve, make the flue-gas temperature that enters the SCR reactor can satisfy the Applicable temperature that puts into operation of SCR reactor, therefore, by increasing the flue gas temperature elevation system, guarantee SCR reactor normally operation under underload and/or atmospheric temperature low condition of the dum boiler of former Natural Circulation, thereby guaranteed that the Natural Circulation dum boiler fume emission quality under the subcritical and super-pressure under underload and/or the atmospheric temperature low condition also can be up to state standards.
Further, a kind of Natural Circulation dum boiler of flue gas temperature elevation system that has of the present invention is by the transformation of water side, effectively solved low and the problem that SCR reactor that cause is stopped transport of under underload and/or atmospheric temperature low condition SCR reactor inlet cigarette temperature, other method than the water side has the amplitude that promotes flue-gas temperature big, and system is simple, investment for trnasforming urban land is few, to the little characteristics of other operating mode influence.Further comparing maximum characteristics of the present invention with the fume side remodeling method is little, the small investments of The reconstruction scope, and the construction time is short.
Further, a kind of Natural Circulation dum boiler that has the flue gas temperature elevation system of the present invention can be saved investment cost over half at least with economizer classification raising cigarette temperature method commonly used at present.
Description of drawings
The schematic diagram of Fig. 1, the former water effluent of Natural Circulation dum boiler journey;
Fig. 2, have the schematic diagram of water effluent journey of the Natural Circulation dum boiler of flue gas temperature elevation system;
The graph of a relation of the situation that puts into operation of the SCR reactor of Fig. 3, subcritical 300MW Natural Circulation dum boiler and unit load, ambient temperature;
The structural representation of Fig. 4, subcritical 300MW Natural Circulation dum boiler;
Fig. 5, have the structural representation of the subcritical 300MW Natural Circulation dum boiler of flue gas temperature elevation system.
The specific embodiment
Also by reference to the accompanying drawings the present invention is further set forth below by concrete Application Example, but do not limit the present invention.
Application Example 1
With a kind of Natural Circulation dum boiler that has the flue gas temperature elevation system, be that example is introduced with subcritical 300MW dum boiler namely.
One, the subcritical 300MW Natural Circulation dum boiler with certain power plant is example, and this subcritical 300MW Natural Circulation dum boiler technical parameter is as follows:
Superheated steam (MCR) reheated steam (MCR)
Flow 1025 t/h flow 830t/h
Pressure 18.3 Mpa pressure 3.85/3.66Mpa
323/541 ℃ of 541 ℃ of temperature of temperature
The SCR reactor moves the requirement for the smoke inlet temperature:
Inlet temperature≤314 ℃ warning
314 ℃＜inlet temperature＞308 ℃ time-delay 1h stop to spray ammonia
Inlet temperature≤308 ℃ stop to spray ammonia SCR and stop transport
The unit load size influences boiler economizer outlet cigarette temperature, namely directly influences SCR reactor inlet flue-gas temperature.Outer atmospheric temperature and this power plant load affect the operational percentage of SCR reactor denitration.Ambient temperature is more low, and putting into operation of SCR reactor will be at the boiler high-load region.
The SCR reactor put into operation situation and unit load, ambient temperature relation as shown in Figure 3, as can be seen from Figure 3:
When ambient temperature is more low, unit is when high load capacity, and the SCR reactor just can put into operation.For example, ambient temperature is in the time of 10 ℃, and unit is below 190MW load, and economizer exhaust cigarette temperature just can not reach the SCR reactor condition that puts into operation;
When ambient temperature raise, for example, ambient temperature was in the time of 35 ℃, and unit is more than 140MW load, and economizer exhaust cigarette temperature can reach the SCR reactor condition that puts into operation.
In a word, unit is when 140MW load is following, and the economizer exhaust gas temperature can't satisfy the SCR reactor condition that puts into operation.
Two, subcritical 300MW Natural Circulation dum boiler original system and operating mode
The structural representation of subcritical 300MW Natural Circulation dum boiler comprises boiler, drum, economizer, SCR reactor, air preheater as shown in Figure 4, and the down-comer of drum is connected with the following water bag of boiler.
When unit when 35% rated load (136MW), its system operational parameters is as shown in Figure 4.In boiler 35% rated load (136MW), boiler fuel flow 650t/h, economizer feedwater flow 365.5t/h, 396 ℃ of economizer gas approach temperature, 224.7 ℃ of economizer feed-water inlet temperature, economizer is given 265 ℃ of water outlet temperatures.At this moment, 290 ℃ of economizer exhanst gas outlet temperature are lower than 314 ℃ of the minimum temperatures that the SCR reactor puts into operation.Therefore, must improve boiler economizer outlet cigarette temperature, thereby improve the SCR reactor inlet temperature, namely satisfy 314 ℃ of the minimum temperatures that the SCR reactor puts into operation, thereby the SCR reactor is put into operation.
Three, have the subcritical 300MW Natural Circulation dum boiler of flue gas temperature elevation system, put into operation with SCR reactor under the condition that is implemented in underload.
Have the flue gas temperature elevation system subcritical 300MW Natural Circulation dum boiler structural representation as shown in Figure 5, comprise boiler, drum, economizer, SCR reactor, air preheater, also comprise the flue gas temperature elevation system, described flue gas temperature elevation system comprises the i.e. i.e. i.e. adjustment doors 3 among the figure of non-return flap 2 among the figure, electric control valve of isolating door 1 among the figure, check-valves of water pump, switch valve;
The down-comer of described drum is connected with the following water bag of boiler, and the following water bag of boiler is connected with the pump entrance pipeline through isolating door 1, and the outlet conduit of water pump is in parallel with the feed-water intake pipeline of economizer after non-return flap 2, adjustment doors 3 successively.
Four, have the subcritical 300MW Natural Circulation dum boiler operation of flue gas temperature elevation system, its operational factor as shown in Figure 5:
When the subcritical 300MW Natural Circulation dum boiler load that has the flue gas temperature elevation system drops to a certain degree, when the economizer exit flue-gas temperature is lower than the minimum suitable temperature of SCR reactor inlet, stop transport for preventing the SCR reactor, need to start the flue gas temperature elevation system:
At first open isolating door 1, non-return flap 2, water pump puts into operation, then according to economizer entrance feed temperature, adjusts adjustment doors 3 apertures of exit of pump.Thereby adjust economizer exit cigarette temperature, when economizer exit cigarette temperature reaches 315 ℃, stop to adjust the aperture of adjustment doors 3, at this moment, the entrance flue gas temperature that enters the SCR reactor meets the flue-gas temperature that the SCR reactor puts into operation, and the SCR reactor can move.
When the subcritical 300MW Natural Circulation dum boiler load that has the flue gas temperature elevation system raises, when economizer exit cigarette temperature reaches SCR reactor service condition, close the flue gas temperature elevation system, do not influence the normal operation of original subcritical 300MW Natural Circulation dum boiler.
Above said content only is the basic explanation of the present invention under conceiving, and according to technical scheme of the present invention institute
Any equivalent transformation of doing all should belong to protection scope of the present invention.
Claims (2)
1. a Natural Circulation dum boiler that has the flue gas temperature elevation system comprises boiler, drum, economizer, SCR reactor, air preheater, it is characterized in that also comprising the flue gas temperature elevation system;
Described flue gas temperature elevation system comprises water pump, switch valve, electric control valve;
The down-comer of drum is connected with the following water bag of boiler, and the following water Bao Zaijing switch valve of boiler is connected with the pump entrance pipeline, and the outlet conduit of water pump is in parallel with the feed-water intake pipeline of economizer behind electric control valve.
2. a kind of Natural Circulation dum boiler that has the flue gas temperature elevation system as claimed in claim 1 is characterized in that between the outlet of water pump and electric control valve check-valves being installed.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201310128408 CN103196134A (en) | 2013-04-15 | 2013-04-15 | Natural-circulation drum boiler with flue heating system |
| CN2013103169869A CN103343959A (en) | 2013-04-15 | 2013-07-26 | Natural circulating drum boiler with smoke temperature rising system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201310128408 CN103196134A (en) | 2013-04-15 | 2013-04-15 | Natural-circulation drum boiler with flue heating system |
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| CN103196134A true CN103196134A (en) | 2013-07-10 |
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| CN 201310128408 Pending CN103196134A (en) | 2013-04-15 | 2013-04-15 | Natural-circulation drum boiler with flue heating system |
| CN2013103169869A Pending CN103343959A (en) | 2013-04-15 | 2013-07-26 | Natural circulating drum boiler with smoke temperature rising system |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104879743A (en) * | 2015-05-22 | 2015-09-02 | 中国神华能源股份有限公司 | Boiler thermodynamic system and boiler |
| CN106287651A (en) * | 2016-08-16 | 2017-01-04 | 宁夏清远顺合环保科技有限公司 | The SCR inlet cigarette temperature kinetic-control system of a kind of boiler and method |
| CN108826333A (en) * | 2018-06-06 | 2018-11-16 | 华电电力科学研究院有限公司 | A kind of neighbour's furnace intersects the system and its operation method of the wide load denitration of carbonated drink realization |
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| CN103851603B (en) * | 2014-03-17 | 2016-02-17 | 山西新唐工程设计股份有限公司 | The band SCR pulverized-coal fired boiler of compact arrangement |
| CN103939885B (en) * | 2014-03-28 | 2016-03-09 | 上海发电设备成套设计研究院 | A kind of feedwater displaced type economizer system put into operation for denitration device whole process |
| CN104028104B (en) * | 2014-06-24 | 2016-01-13 | 中国电力工程顾问集团华东电力设计院有限公司 | Be provided with denitrification apparatus and the generating set of economizer recirculating system |
| CN108844058B (en) * | 2018-08-16 | 2024-05-17 | 杭州华电能源工程有限公司 | Economizer hot water recirculation system suitable for subcritical steam drum furnace generator set and working method thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2923172B2 (en) * | 1993-06-22 | 1999-07-26 | 三菱重工業株式会社 | Economizer |
| JP2930520B2 (en) * | 1994-04-13 | 1999-08-03 | 三菱重工業株式会社 | Heat recovery unit for boiler with denitration equipment |
| US6609483B1 (en) * | 2002-02-27 | 2003-08-26 | The Babcock & Wilcox Company | System for controlling flue gas exit temperature for optimal SCR operations |
| US7578265B2 (en) * | 2006-05-09 | 2009-08-25 | Babcock & Wilcox Power Generation Group, Inc. | Multiple pass economizer and method for SCR temperature control |
| CN101947413B (en) * | 2010-08-26 | 2013-02-06 | 中材节能发展有限公司 | Glass kiln denitration generating system |
| CN203595114U (en) * | 2013-04-15 | 2014-05-14 | 上海上电电力工程有限公司 | Natural circulation drum boiler with smoke warning system |
-
2013
- 2013-04-15 CN CN 201310128408 patent/CN103196134A/en active Pending
- 2013-07-26 CN CN2013103169869A patent/CN103343959A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104879743A (en) * | 2015-05-22 | 2015-09-02 | 中国神华能源股份有限公司 | Boiler thermodynamic system and boiler |
| CN106287651A (en) * | 2016-08-16 | 2017-01-04 | 宁夏清远顺合环保科技有限公司 | The SCR inlet cigarette temperature kinetic-control system of a kind of boiler and method |
| CN106287651B (en) * | 2016-08-16 | 2018-07-24 | 北京清远顺合环保科技有限公司 | A kind of the SCR inlet smoke temperature kinetic-control system and method for boiler |
| CN108826333A (en) * | 2018-06-06 | 2018-11-16 | 华电电力科学研究院有限公司 | A kind of neighbour's furnace intersects the system and its operation method of the wide load denitration of carbonated drink realization |
| CN108826333B (en) * | 2018-06-06 | 2023-06-23 | 华电电力科学研究院有限公司 | System for realizing wide-load denitration by adjacent furnace cross steam-water and operation method thereof |
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| CN103343959A (en) | 2013-10-09 |
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Application publication date: 20130710 |