At present, there is no particularly perfect technology for boiler nitrogen oxides (NOx), but the harmful effects of nitrogen oxides on the environment in which humans depend and humans themselves are extremely serious: on the one hand, nitrogen oxides are the main cause of acid rain. On the other hand, under certain conditions, NOx can form photochemical smog together with hydrocarbons to destroy the atmospheric environment, seriously endanger human health and deteriorate the environment on which humans depend. With the rapid development of China's power industry, the installed capacity of thermal power has increased significantly year by year, and the problem of NOx pollution will receive more and more attention.
Since its establishment, Dengfeng China Resources Power Co., Ltd. has been practicing the energy-saving and environmentally-friendly production concept, focusing on social responsibility, starting from reality, improving itself as a starting point, continuously improving equipment and facilities, and achieving good social benefits.
Key words: low nitrogen burner, NOx, environmental protection, micro-pulverized coal combustion
1 Overview
The main technical parameters of the boiler are as follows:
2. Design and status of common coal
The design of the project uses the current actual burning coal types, the coal types are medium to low calorific value, medium volatile, high ash, medium full moisture, low sulfur and lean coal. The main components and characteristics of coal combustion are shown in the table below.
At present, the NOx emission level in boiler exhaust is relatively high. Under the load of 250MW, the measured NOx concentration in the tail is 1073/1055mg/m3. Under the 287MW load, the measured NOx concentration in the tail is 1022/1021mg/m3, which is very difficult to reduce.
3, the main design parameters of the burner
The design calculations were carried out for the design of coal types and the verification of coal types. The calculation data of the design coal types are given below.
4, primary air and pulverized coal concentrator
The optimized pulverized coal louver concentrator will be used to ensure low flow resistance, uniform air distribution, high pulverized coal concentration ratio, wear-resistant cast steel structure, durable wear resistance, and high lining at easy wear parts.çž cast iron wear-resistant material. The pulverized coal concentrator has a short total length and can meet the requirements of on-site installation and layout. According to the existing coal quality, the pulverized coal concentrator is optimized to achieve the best ignition, burnout and low NOx emission characteristics, as shown below.
A cooling perimeter wind is arranged around the spout to cool the shutdown spout. The primary air spout adopts a flared structure to delay the mixing between the primary wind and the perimeter wind. The vertical baffle is retained between the primary and the wind, and the wind is delayed between the primary and the wind. mixing. The circumferential wind nozzle offset has the effect of reducing the slagging of the furnace wall and preventing high temperature corrosion.
5, trace oil burner
In view of the characteristics of #2 boiler and fuel combustion characteristics, the four burners of the B layer were changed into a new generation of trace oil direct ignition horizontal concentrated pulverized coal pulverized coal burner, which was used as a boiler ignition burner and a main burner to meet the boiler start and stop. The requirements are as follows.
6, secondary air vents and burnout layers
The secondary air nozzle adopts a contracted structure, delays the mixing of primary and secondary winds, effectively delays the mixing of air and pulverized coal, reduces the chance of reaction between N-containing groups and O2 in the combustion process, and effectively reduces the amount of NOx generated.
The secondary air nozzle adopts a contracted structure to delay the mixing of a secondary air. The area of ​​the secondary air vents in the main burner zone is correspondingly reduced according to the degree of reduction of the organized secondary air in the main burner zone, ensuring that the secondary wind speed of the outlet reaches a higher wind speed. The area of ​​the larger secondary air vent is ensured to have a larger outlet secondary wind momentum, which plays the role of powder in the lowermost layer, reducing the amount of slag at the bottom of the furnace and the carbon content of the large slag. The secondary wind cut circle arrangement has not changed, the same as the original design.
The high-level burnout system distributes the organized combustion air volume along the vertical direction of the furnace. The ratio of the amount of organized air in the main combustion zone to the theoretical air volume changes from λp=1.25 to λp=0.875~0.9375. At the elevation of 29m and 32m above the main burner, four layers of 16 air-fired vents are arranged, and the burnt-out wind will be placed at the four corners of the furnace.
The entire burnout air vent is opened at the corner of the same water-cooling wall at the upper part of the burner zone. The burn-out air volume accounts for about 25% to 30% of the total air volume, and the wind speed of the burnt air vent is 45m. /s~50m/s, the burnout air nozzle can swing vertically and horizontally, ±15° vertical, ±10° horizontally, according to boiler operating conditions (burnout, NOx emission, superheater steam temperature deviation) Etc.) Make appropriate adjustment of the nozzle angle to effectively adjust the smoke temperature deviation at the exit of the furnace and ensure that there is no overheating problem in the superheater tube wall.
According to the pre-reform test, the NOx emissions of the two boilers in Dengfeng Phase I:
Through the low-nitrogen burner and damper modification, the NOx emission value of the boiler outlet is reduced, the thermal deviation of the heating surface is reduced, the cost of the denitrification agent and other auxiliary consumable materials can be saved, and the resources such as ammonia gas, steam, fuel oil and the like are saved. The transformation of the project is in full compliance with the actual characteristics of the equipment of the Dengfeng project.
7, the conclusion
In the case of increasing national environmental protection requirements and increasing liquid ammonia prices, it is more important to configure the denitration system of the thermal power plant and reduce the environmental protection indicators through boiler combustion adjustment during operation, thereby ensuring the safe operation of the unit and improving the unit. Economic benefits.
Summary: This paper has modified the boiler combustion system and achieved certain results, but it needs further research and discussion on the boiler combustion process and operation optimization adjustment to achieve better results, but due to the author's lack of ability and time. The limitations of the work, there are still imperfections in the work, and further research and analysis are needed.
Laptop power adapter charger for HP:
Laptop Brand
Power Adapter
EliteBook 8440p 6530b
18.5v 3.5a, 7450
Compaq 6500b 6530b 6535b 6700b 6730b 6735b 6736b
19v 4.74a, 7450
Pavilion DV4 DV5 DV6-1000 CQ60 CQ61
18.5v 3.5a, 7450
COMPAQ Mini
19v 1.58a, 4017
2710p 2730p 2740p 2740w 2760p
18.5v 3.5a, 7450
Pavilion DV4 DV5 DV5T DV6 G50 G60 G70 HDX16
18.5v 3.5a, 7450
dm4-1000 Dm4t-1000 Dm4t-1100 DV3-4000 CQ42
18.5v 3.5a, 7450
Compaq Presario CQ42 CQ57 CQ72 CQ56 CQ32 CQ32-101TX I84C
18.5v 3.5a, 7450
G62 Compaq Presario CQ42 CQ72 CQ62 CQ56 CQ32 593555-001 DM4
18.5v 3.5a, 7450
DV4 DV5 DV6-1000 DV6-1200 DV6-1300
18.5v 3.5a, 7450
DV4 SPARE
18.5v 3.5a, 7450
dv4-1120us dv4-1200 dv6-2150us dv6-2155dx dv6-1245dx
18.5v 3.5a, 7450
Pavilion DV1000 DV1100 D1200 DV1300
18.5v 3.5a, 4817
DV1000 M2000
18.5v 3.5a, 4817
EliteBook 2730p 2740 2760p Compaq 2710p nc6320
18.5v 3.5a, 7450
Compaq 320 321 325 326 420 620 621 421
19v 4.74a, 4817
Pavilion dv4000 dv4100 dv4300 dv4400
19v 4.74a, 4817
Compaq DV1000 G3000 G5000
18.5v 3.5a, 4817
dv4-5000 dv6-7000 dv7-7099
19v 4.74a, 4817
dv6-7200 dv7-7200 DV4-5000 DV7-7000
19v 4.74a, 4817
DV4 DV6 CQ60 CQ70 G50 G70
18.5v 3.5a, 7450
ProBook 4340s 4341s
19v 4.74a, 7450
Pavilion DV3
19v 4.74a, 7450
ProBook 4320s 4321s 4325s 4420s 4425s 4525s
18.5v 3.5a, 7450
dv2000 dv6400 dv6700 dv6800 dv6900 A900 V6400
18.5v 3.5a, 4817
Compaq 420 421 425 4320t 620 625 320 321 325 326 621
18.5v 3.5a, 7450
ProBook 6440b 6445b 6450b 6540b 6545b 6550b 6555b
19v 4.74a, 7450
Pavillion DV7
19.5v 4.62a, 7450
G42 G72 G32 DV7-4000 DV6-6000 DV5-2000
19.5v 4.62a, 7450
Presario CQ32 CQ42 CQ43 CQ56 CQ62 CQ72
19v 4.74a, 7450
Pavilion DV6 DV6-3000 DM4-1000 Envy 15 17 G4 G6 G7-1000
19.5v 4.62a, 7450
avilion dm3 dm3-dm3t-1000 CTO dm3-1000 dv4-3100
19.5v 3.33a, 4817
DV4 DV5 G50 G60 G61 G70 G71 HDX16
19v 4.74a, 7450
CQ40 CQ50 CQ60 CQ61 CQ70 CQ71 DV4
19v 4.74a, 7450
CQ60 CQ61 CQ40 CQ41 CQ45 CQ60 G60 G70
19v 4.74a, 7450
Pavilion dm3 CTO dm3-1000 dv4-3100
19v 4.74a, 7450
Compaq 6520 6520P 6520S 515 516
19v 4.74a, 7450
2000-425NR
19v 4.74a, 7450
Our service:
Stable output and high charging efficiency.
Elegant outlook design as original one, touch smoothly and comfortable.
Original charger is good, but as a replacement, our product has more reasonable price when your original charger is broken.
And, the market of the replacement adapters becomes bigger and bigger. People would rather buy a copy one then the original because of the price.
But at the same time, people worry about that they will buy something defective. So the problem comes, how to buy a good quality one with a good price?
As a professional power adapter manufacturer, we have excellent R&D team, skilled staffs and responsible after-sale service. All your benefits can be under protected after you buy products for our company.
Our certificates :ISO9001:2008 & ISO14001:2004 , CCC , CE , FCC , ROHS.
All our products has 1 year warranty. In other words, if you get the dad products which are not damaged physically from us in one year, we will replace you the new one or the whole bulk order.
Laptop Adapter For Hp,Hp Laptop Adapter,Charger For Hp,Power Supply For Hp
Shenzhen Waweis Technology Co., Ltd. , https://www.szwaweischarger.com