The develpment of the CFB boilers anti abrasion technology

Maybe many people ever heard about the CFB anti-wear beams technology , now this technology has been updated into new generation anti wear technology -----Wuhan Yongping Grille Anti-wear Technology . The Grille anti wear technology now can eradicate the CFB tubes abrasion completly , so far there are more than 200 CFB boilers all over the world ever used this technology and this technology can prevent the tubes leaking at least 5 years , according to the situations of the CFB boilers used the grille anti wear technologies .

Here we will introduce the technology changes history about the CFB tubes anti abrasion development . Circulating fluidized bed boiler furnace process determines that there is a "ring-core" flow structure in the furnace, in the center of the furnace gas upward movement, around the wall flow downward flow, and the downward flow rate is increasing. In the process of flowing downward to the wall, the water wall has been seriously eroded for a long time. For the CFB boiler burning high ash and poor quality coal, the problem of water wall wear is more prominent.

In the early stage of CFB boiler, the abrasion-proof measures such as tube release, anti-abrasion bump, anti-abrasion protective tile and metal spraying can slow down the abrasion rate of water-wall to a certain extent, but it is difficult to solve the problem of water-wall abrasion thoroughly.

_active multi-stage anti-wear device reduces the concentration and velocity of wall-adherent flow step by step. The anti-wear device can effectively reduce the wear of water wall and prolong its service life. Within one year of operation, 30-50 points were randomly selected from the CFB boiler water wall tubes (bottom-up basically uniform), the thickness of tube wall thinning at 100% sampling points was less than 0.6 mm, and the thickness of tube wall thinning at 80% sampling points was less than 0.4 mm. The anti-abrasion device not only improves the operation economy of power enterprises, but also provides reliable protection against abrasion of water wall for CFB boilers burning inferior coal fuel.

Technology innovation

_(1) Adopting active anti-wear device, the adherent flow changes the flow direction when it meets the anti-wear device, and accelerates the flow downward instead of moving toward the center of the furnace, which obviously reduces the adherent flow concentration and reduces the wear of the water wall of CFB boiler;

_(2) Adopting multi-stage anti-wear structure, the wall-adherent flow is divided into several sections, which can obviously reduce the velocity of wall-adherent flow and reduce the wear of water-wall of CFB boiler;

_(3) Adopt trapezoidal anti-wear structure to avoid local eddy current wear at the junction of anti-wear device and water wall;

_(4) The anti-wear device is arranged in the way of "upper dilution and lower density". It not only effectively realizes the anti-wear of the water wall of CFB boiler, but also realizes that the anti-wear device has little effect on the heat transfer coefficient and ensures the heat absorption of the water wall. It

Principle explanation
It is generally believed that the wear rate of water wall is closely related to the flow velocity, particle size, material concentration and the inhomogeneity of flow field. The specific relationship is as follows: E = kWaD2U_.

The wear rate: (m/100h)

The coefficient of proportionality (-)

Material velocity (m/s)

Speed index (3 to 3.5)

Particle size (mm)

Material concentration (kg/ (M2? S))

From the above formula, it can be seen that the wear rate of wall-to-wall flow is proportional to the 3-3.5 power of the flow rate of wall-to-wall materials. From the point of view of reducing the velocity and concentration of wall-to-wall flow around the wall, the active anti-wear device of water wall adopts multi-stage arrangement. Fig. 1 is a schematic diagram of the anti abrasion mechanism of the CFB water wall active anti abrasion device.
Such

Fig. 1CFB schematic diagram of the anti abrasion mechanism of the boiler water wall active anti abrasion device

Application performance

By the end of 2011, 39 300 MWCFB boiler units had successfully installed active water wall anti-wear devices, exceeding 3/4 of the 300 MWCFB boilers that have been put into operation. The operation of the boiler after installing the water wall active anti-wear device shows that the installation of the anti-wear device has little effect on the main operation parameters of CFB boiler.

It



Name of power plant

Unit capacity
Boiler factory

install date

Name of power plant

Unit capacity
Boiler factory

install date

Henan Pingdingshan Rui Ping Coal Co., Ltd.

2 x 480t/h
Dongfang Boiler Works

2006.12 (#1)

2007.02 (#2)

Datang Honghe Power Plant

2 x 1025t/h
hbc

Two thousand and eight point zero eight

Shanxi Jinneng group Datong thermoelectric Co., Ltd.

2 x 480t/h
hbc

Two thousand and seven point five

China's West Lai Feng power plant

2 x 690t/h
Dongfang Boiler Works

Two thousand and nine point one two

Tianjin Chen Tang Thermal Power Co., Ltd.

1 x 440t/h
hbc

Two thousand and seven point seven

Shenhua Shendong Electric Power Co., Ltd.

4 300MWCFB boilers

Two thousand and nine point one two

Henan Zhongfu Electric Power Co., Ltd. two branch company

1 x 440t/h
Shanghai Boiler Works

Two thousand and seven point one two

Tengzhou low calorific value Thermal Power Co., Ltd.

Ji'nan Boiler Works
2 x 240t/h

Two thousand and ten point four

Erdos Double Power Generation Co., Ltd.

2 x 440t/h
Ji'nan Boiler Works

Two thousand and eight point zero three

Zaozhuang south suburb thermoelectric Co., Ltd.

hbc
2 x 240t/h

Two thousand and ten point seven

Wuhai Jun Zheng Energy Chemical Co., Ltd.

1 x 470 t/h
Dongfang Boiler Works

Two thousand and eight point zero five

Guizhou Huadian Bijie Thermal Power Co., Ltd.


Dongfang Boiler Works
2 x 490t/h

Two thousand and ten point seven

Henan Luoyang sunshine thermal power plant

1 x 440 t/h
Dongfang Boiler Works

Two thousand and eight point zero nine

Shenhua Coal Oil Co., Ltd.

Wuxi Boiler Works
3 x 410/h

Two thousand and ten point four

Ningbo Sinopec Zhenhai Refining and chemical branch company

1 x 450 t/h
FOSTER WHEELER

Two thousand and eight point one one

Huaneng suer thermoelectric Co., Ltd.

Shanghai Boiler Works
2 x 240t/h

Two thousand and ten point three

Huadian Wuda Power Generation Co., Ltd.

2 x 480 t/h
Dongfang Boiler Works

2008.05 (#1)
2008.10 (#2)

Huaibei Lihuan Zhongli Power Generation Co., Ltd. two phase

hbc
2 x 1100t/h

Two thousand and ten

Qinhuangdao Qin Heat Power Co., Ltd.

2 x 1025t/h
Dongfang Boiler Works

2008.05 (#5)
2008.10 (#6)

Fujian Huadian Zhangping Thermal Power Co., Ltd.

Dongfang Boiler Works
2 x 1025t/h


Two thousand and ten point nine

Huaibei Lihuan Zhongli Power Generation Co., Ltd.

2 x 1025t/h
hbc


Two thousand and eight point zero four

Fujian Huadian Yongan Power Generation Co., Ltd.

Dongfang Boiler Works
2 x 1025t/h

Two thousand and ten point one one

Guodian Kaiyuan Power Generation Co., Ltd.

2 x 1025t/h
Shanghai Boiler Works

Two thousand and eight point zero six
Two thousand and nine point zero eight

With coal power Wang Ping Power Generation Co., Ltd.

2 x 725t/h
Huaxi boiler factory

Two thousand and eleven point nine

Guangdong Bao Li Hua power Co., Ltd.

2 x 1025t/h
Dongfang Boiler Works

Two thousand and eight point zero nine

Huadian Sujiatun Thermal Power Co., Ltd.

2 x 670t/h
Wuxi boiler