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Taiyuan Boiler Group Co., Ltd.
Design and Application
of Low Emission CFB Boiler with Energy-saving Technology
2014.05.05
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Cooperating with Tsinghua University, Taiyuan Boiler Group Co., Ltd achieved a major breakthrough in the field of CFB boiler . Its technology and products have been identified by the Ministry of Education, and won the second prize of National Scientific and Technological Progress Award.
Expert Conclusion: The energy-saving CFB boiler of Taiyuan Boiler Group Co., Ltd , with completely intellectual property rights, has significant advantages in auxiliary power saving and anti-abrasion. It has reached the advanced level.
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75t/h
130t/h
220t/h
480t/h
At present, Taiyuan Boiler Group Co., Ltd has developed a series of energy-saving CFB boiler, with capacity from 75t/h to 1025t/h. The amount of CFB products under operation from 75 to 220t/h is more than 100. The 1000t/h level of CFB boiler is being installed and will be put into operation next year . 1025t/h
2-925t/h CFB boiler being installed
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Technical Advantages Saving 30% of the fan energy consumption
Saving 2-3% of the coal consumption
Low abrasion: Continuous runtime: more than 6500 hours
Runtime per year: more than 8000 hours
Low emission: High desulphurization efficiency: higher than 95% when the Ca/S is 2.
Low original emission of NOx : lower than 120mg/Nm3 for anthracite and lean coal;
lower than 200mg/Nm3 for bituminous coal and lignite
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1. Design Principle of the Products
Key points of the design 1. According to the design theory of Tsinghua University, the proper fluidized
air velocity and circulating rate are chosen to make the flow regime stay in compound state of fast fluidization and turbulent fluidization.
2. High efficient cyclone is chosen. High flow rate, self-balance returning valve is
chosen, each of the valve is equipped with a roots blower. The boiler can run stably with low bed pressure, which can reduce the abrasion
of heating surface. 3. Air distributor system: applying the water-cooled distributor, low resistance wind caps. Preposed wind chamber is used to distribute the primary air uniformly. 4. Design of secondary air: a single layer of secondary air inlets is arranged to increase its penetrant power
5. The abrasion, expansion and seal should be considered in the design, and the components should be assembled in workshop as many as possible to maintain the quality.
6. Low Emission Design: In BMCR,the bed temperature should be lower than 880℃ for low emission
purpose. .........
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2. Operating results of Products
The first 220t/h energy-saving CFB boiler located in Hailaer, Inner Mogolia
DCS控制画面
Power of air fan in Hailaer CFB boiler
5#(TY) 3、4#
Primary air fan(KW) 900 1420
Secondary air fan(KW) 560 710
Roots blower(KW) 37 110
Induced draft fan(KW) 1260 1420 Total power(KW) 2757 3660 Energy saving(KW) 903
Energy saving percent(%) 32.7%
Electric current 5#(TY) 3、4# save
primary air fan(A) 34 51 33%
secondary air fan(A) 18 22 18%
Induced draft fan(A) 61 76 20%
Roots blower(A) 65 190 66%
At the rated load, the air fan could save 550 kWh per day, namely 4.4 million kWh per year, according to 8000 hour running time per year. Because the #5 boiler operated at over load all the year round, it can save 500 thousand kWh per month.
Coal consumption 5#(TY) 3、4#
Coal consumption(t/h) 55 56.4
Saved coal(t/year) 11000
Saved coal per year(%) 2.5%
Since 2008, the Hailaer 220t/h CFB boiler has been running in full load, even over load. There is rarely abrasion in the heating surface.
240t/h energy-saving CFB boiler located in Xing’an power plant
At full load, the bed pressure is 6.5KPa, bed temperature is 850℃
3#(TY) 1、2#
Primary air fan(KW) 710 1250
Secondary air fan(KW) 560 900
Roots blower(KW) 3×15 2×160
Induced draft fan(KW) 2×630 2×630
Total power(KW) 2453 3730
Energy saving(KW) 1155
Energy saving percent(%) 47%
Power of air fan in Xing’an CFB boiler
Comparison of 130t/h CFB boiler in Shengzhou
Before reforming: T = 950℃、P = 9.3KPa
After reforming: T = 930℃、P = 7.6KPa
Energy consumption of fan reduces 30%. Carbon content of fly ahs reduce from 7.4% to 2.6%.
Comparison of pollutant emission
#4: T = 930℃,NO2 = 458mg/m3, SO2 = 306mg/m3 #5(TY): T = 880℃,NO2 = 113mg/m3, SO2 = 97mg/m3
Flue gas components of TG260/9.81 CFB boiler in Xiang’yang power plant
CO /mg·m-3
NO /mg·m-3
NO2 /mg·m-3
N2O /mg·m-3
SO2 /mg·m-3
H2O /%
O2 /%
NOx/mg·m-3
SO2/mg·m-
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CASE1——12:48
293.9 58.4 10.0 38.9 544.0 2.9 3.9 90.4 495.3
295.1 57.6 10.0 38.7 546.8 3.0 4.3 91.6 510.9
289.3 56.7 11.6 36.3 485.4 3.5 4.4 93.0 459.4
294.0 55.1 10.8 38.5 538.9 3.3 3.8 86.5 490.2
CASE2——13:22
403.0 58.4 10.4 18.2 663.1 4.3 2.5 85.1 565.8
393.5 57.6 10.8 17.1 688.9 4.4 2.7 85.4 595.3
387.5 57.6 11.2 14.7 698.8 4.5 2.7 85.9 604.6
379.2 58.4 11.2 14.7 714.7 4.5 2.5 86.0 611.3
NOx emission is lower than 100mg/m3, satisfying the new environmental standards
NOx emission of 95t/h CFB boiler in Huimei, Sichuan
Burning Furong lean coal,original NOx emission is 88mg/Nm3
Thank you