the challenge and sustainability of circulating fluidized ... _the challeng… · the challenge and...

The Challenge and Sustainability of Circulating Fluidized Bed Boiler

in China: Problems and Solutions

HUANG ZHONG, Huaneng Clean Energy Research Institute, 86+10-89181277,

[email protected]

LIU GUANJIE, Huaneng Clean Energy Research Institute, 86+29-82102004, [email protected]

YANG JUAN, China Electricity Council of Science and Technology Development Service Center,

86+10-63253527, [email protected]

[ABSTRACT]

China is the largest manufacturing country of Circulating Fluidized Bed(CFB) boiler. So far there are

more than 6,000 CFB boilers in operation, whose capacity ranges from small-scale hot water boiler to

large-scale supercritical boiler. The reliability, economy and control of the pollutant emission of CFB

boiler have been improved remarkably by Chinese CFB technicians with their hard works. China has

got abundant experience in design, manufacture, installation, operation, maintenance, and

management of CFB boiler, and plays a key role in sustainable development of CFB boiler technology.

[Key Word]

CFB Boiler, Design, Optimization, Retrofit, Experience, Reliability

Introduction

China is the major coal producer and consumer in the world. The special resource conditions of China

determines that coal would be the main energy source of Chinese power industry for a long time. By

the end of 2015, the installed power capacity in China has reached 1,507 GW, among which coal-fired

power capacity is 884 GW. Large part of the coal reserves in China is the low quality species, such as

high ash coal, high-sulfur coals, low calorific value coal and hard-fired coal. Circulating Fluidized Bed

(CFB) boiler has played an important role in high efficient utilizing of coal resource due to its excellent

fuel flexibility and environmental friendly performance. It developed as the beneficial supplement of

pulverized coal boiler rapidly. Chinese major power company and coal production enterprises have

CFB generating units of different scales. The applications of CFB include power generation, waste rock

consumptive, petroleum and petrochemicals, nonferrous metallurgy and papermaking.[1]-[3] The

reliability, economy and pollutant emission of CFB boiler have been improved remarkably by Chinese

CFB technicians with their hard work in recent years. China has got abundant experience in design,

manufacture, installation, operation, maintenance, and management of CFB boiler.[4]

1 CFB boiler technology development status in China

1.1 Units distribution

By the end of 2015, the CFB units with above 100MW capacity has been installed nearly 70 GW in

China (Figure 1). China has the largest number of CFB units in operation, the largest total installed

capacity and the most advanced technology in the word. Currently, 135M and 300MW units are the

main models of large-scale CFB units in China, which take up to 82.4% of the total installed capacity

and 79.3% of the total installed number.

Chinese boiler manufacturers have manufactured and provided 48 CFB boilers for overseas market,

and the total supply capacity ha

exported to the Southeast Asian power market. In addition, the number of supercritical CFB boiler in

Chinese market has reached to 10,

generation of CFB boiler with ultra

characteristics is the main direction of its

ultra-supercritical, 1000MW supercritical,

“China manufacturing 2025”

Fig.1 Distribution of large

Fig.2 Development of supercritical CFB boilers in China

1.2 Research progress

China has worked on the development and application of

the joint role of technology introduction and independent development, Dongfang boiler Co., Ltd,

Harbin boiler Co., Ltd, Shanghai boiler Co., Ltd and other major boiler manufacture

Huaneng Clean Energy Research Institute (the predeces

Thermal Power Research Institute

of Engineering Thermophysics

succession. Steam parameters of boiler

pressure, subcritical to supercritical.

boilers putting into operation in China, 15% of the installed capacity

boiler technology improves

independent theory of CFB design. Along with

subcritical, 600MW and 350MW

the total supply capacity has reached 6.54 GW, in which a considerable number of them

outheast Asian power market. In addition, the number of supercritical CFB boiler in

Chinese market has reached to 10, with a total installed capacity of 3750MW (Figure 2). The third

generation of CFB boiler with ultra-low emission capability and low power consumption

direction of its development in China. The R&D program of 600MW

1000MW supercritical, and ultra-supercritical CFB boiler have been included in

Fig.1 Distribution of large-scale CFB boilers in China

Development of supercritical CFB boilers in China

has worked on the development and application of large-scale CFB boiler since the 1980s


Co., Ltd, Shanghai boiler Co., Ltd and other major boiler manufacture

Huaneng Clean Energy Research Institute (the predecessor of which is CFB boiler

Thermal Power Research Institute, TPRI), Tsinghua University, Chinese Academy of Sciences Institute

and other Research Unit have designed 100MW~600MW CFB boiler in

parameters of boiler have extended gradually from high pressure, super

, subcritical to supercritical. [5]-[7] In this process, there were more than 6000 units

into operation in China, 15% of the installed capacity of coal-fired power. Chinese CFB

gradually in competing against foreign technology,

CFB design. Along with the Chinese owned intellectual property

subcritical, 600MW and 350MW supercritical CFB units has been put into operation, China has fully

a considerable number of them were

outheast Asian power market. In addition, the number of supercritical CFB boiler in

MW (Figure 2). The third

low power consumption

he R&D program of 600MW

been included in the

since the 1980s. Under


Co., Ltd, Shanghai boiler Co., Ltd and other major boiler manufacturers, as well as

is CFB boiler division of Xi’an

), Tsinghua University, Chinese Academy of Sciences Institute

and other Research Unit have designed 100MW~600MW CFB boiler in

have extended gradually from high pressure, super-high

In this process, there were more than 6000 units of 75t/h CFB

fired power. Chinese CFB

technology, and forms a

intellectual property of 300MW

put into operation, China has fully

mastered the core technology of CFB. Boiler manufacturers have been able to design and produce CFB

independently, and take as high as more than 95% Chinese market (Figure 3).

Fig.3 Major CFB boiler manufacturers market share in China

Chinese CFB boiler technology not only contains advanced design concepts, more importantly, it forms

a complete design manufacture, installation, operation and maintenance system. As the leader of CFB

technology all over the world, China published nearly 800 journal papers in the field of CFB power

generation technology, and applied for nearly 300 patents(Figure 4).

(a)the number of papers published; (b)the number of patent application

Fig.4 CFB boiler research statistics in China

2 Main problems of CFB boiler suffered in China

Compared to conventional pulverized coal boilers, CFB boiler exposed some inevitably problems in its

fast development, especially the lack of design experience in early stage, inadequate concern in

operation conditions for burning low-grade fuel, which resulting in some typical problems in operating

CFB boilers.[8][9] These problems include:

The abrasion of the water wall of the furnace, especially in the transition zone of emulsion zone

and splash zone; the four corners of furnace; the top of furnace; the outlet of furnace;

walls-through zone of platen heat surface and other parts of the units; the continuous operation

period is short.

The abrasion of air nozzle, poor air distribution, coking of slag and slag leakage in wind box

caused by un-uniform fluidization. A lot of air nozzle need to be replaced in each shutdown

maintenance.

The damage of wear-resistance materials and refractory materials in furnace interior, separator

and refeeder affects the operation.

Stacked coal in the furnace in operation, failure of coal transferring, burning of transfer belt, etc,

causes the cease of coal supply.

Frequent blocking and un-functioning of slag cooler and transferring system greatly effect the

operation of power plants.

The in appropriated designation of heating surface causes the lower or higher temperature than the

designed values of superheater, reheater and other heat exchanger.

High carbon content in bottom slag and fly ash, high exhaust gas temperature and low combustion

efficiency.

High auxiliary power ratio; high consumption rate of coal for unit power supply; poor unit

economic.

Low automatic control rate, which results in large operating intensity for operators.

High concentrations of sulfur dioxide and nitrogen oxide emissions, which causes largely used of

limestone.

Fortunately, these problems have been resolved with the great efforts of Chinese technical staffs. The

reliability, economy and environmental protection of Chinese CFB boiler have reached the same level

of conventional pulverized coal on in recent years. 87 typical CFB boilers’ operation data have been

calculated and statistical analyzed in 2014, and the correlation results are included in the ‘3.Technical

specifications’.

3 Technical specification

3.1 Unplanned outage times

The number of unplanned outage times reflects the level of production management and operation. The

combustion mode of CFB boiler is different from the pulverized coal fired boiler. After mixing with a

large number of materials, particles of burning coal combusts in circulating fluidized state in the

furnace. Because of the low calorific value and high ash content of burning coal, the water wall of the

furnace is badly worn. CFB boiler is called the “week boiler" and "month boiler” at the beginning of

operation in China; in 2005, the average times of unplanned outage of China's circulating fluidized bed

boiler was 3.85 times per year. [10][11] This is mainly because that at the beginning of the operation,

continuous operation of CFB boiler is too short, and forced outages often occur every week or month

due to various problems. With increasing experience of operator on the operating rule of furnaces, and

the promotion of new anti-wear technology, continuous operation time extended continuously. At

present, long period operation of 8~10 months has been realized for most CFB boilers. In 2014, the

average of unplanned outages of 87 typical CFB is 0.39 times per year per unit. Among these, the

average of unplanned outages for CFB of 135 MW is 0.29 times per year per unit and the the average

of unplanned outages for CFB of 300 MW is 0.48 times per year per unit, which are about the same as

pulverized coal fired boiler. Especially, Heshuyuan power plant obtains the longest continuing

operation time of 434 days for the 300 MW CFB, while it is 311 days for the 135 MW CFB in Pansan

power plant.

3.2 Service hours and available hours

Servicing hour refers to the number of hours that the device is in running. In 2014, the average

servicing hour of 87 typical CFB boilers was 6779 hours. Among these, the average servicing hour of

135MW CFB boilers was 6827 hours, and the average servicing hours of 300MW CFB boilers was

6735 hours.

Available hours is equal to the sum of the servicing hours and reserve shut down hours of boiler unit,

and it is an important indicator reflecting the reliability management. In 2014, the average available

hour of 87 typical CFB boilers was 6779 hours. Among them, the average available hour of 135MW

CFB boilers was 6827 hours, and the average available hour of 300MW CFB boilers was 6735 hours.

3.3 Net coal consumption and auxiliary power ratio

Net coal consumption and auxiliary power ratio are two of the most important indexes to measure the

Energy efficiency level of unit. The efficiency of boiler is low for the reason that CFB boiler is mainly

fueled by poor quality fuel. Therefore, net coal consumption and

higher than that of pulverized co

power ratio of 87 typical CFB boilers were 343.8g/kWh and 7.8%. Among them, the average net coal

consumption and auxiliary power ratio

8.0%, and the average net coal consumption and

respectively 340.1g/kWh and 7.5%.With the development of technology and design concept, the

auxiliary power ratio of some 300MW CFB boilers can be reduced to abo

narrowing the gap compared with the traditional pulverized coal boiler.

4 Solutions for the problems

4.1 Abrasion prevention

The circulating solids in CFB boiler furnace has two basic movements: upward movement for solids in

furnace center, and the approximate free fall

shows that wall abrasion rate of solids is proportional to

concentration of solids near the wall.

high concentration and flow rate of

Fig.

In China, the effective means to deal with CFB boiler abrasion is to add active multi

anti-abrasion beams, this technique

near the wall. The test results showed that adherent flow rate can be reduce

after using this technique additionally

technology has been widely used

continuous operation of CFB boiler more than

lesser extent (Figure 7).

(a) structure of anti

Fig.6 Diagrammatic sketch of

Therefore, net coal consumption and auxiliary power ratio

higher than that of pulverized coal boiler. In 2014, the average net coal consumption and

of 87 typical CFB boilers were 343.8g/kWh and 7.8%. Among them, the average net coal

auxiliary power ratio of 135MW CFB boilers were respectively 347.0g/kWh

8.0%, and the average net coal consumption and auxiliary power ratio of 300MW CFB boilers

and 7.5%.With the development of technology and design concept, the

of some 300MW CFB boilers can be reduced to about 4%, which significantly

narrowing the gap compared with the traditional pulverized coal boiler.


approximate free fall near the wall for solids in surrounding furnace

that wall abrasion rate of solids is proportional to the 3.5 order of mass velocity

concentration of solids near the wall.[11] The main reason for serious abrasion in transition region is

high concentration and flow rate of circulating solids near the wall (Figure 5).

Fig.5 Some typical abrasion of CFB boiler

In China, the effective means to deal with CFB boiler abrasion is to add active multi

, this technique is showed in Fig 8, by setting projections on wall to

near the wall. The test results showed that adherent flow rate can be reduced from 8m/s to 3m/s or less

additionally, significantly reduce the abrasion of furnace heating surface. This

has been widely used in China in recent year, and the use of this technology ensures

continuous operation of CFB boiler more than 6,000 hours and control heating surface abrasion to a

(a) structure of anti-abrasion beams; (b) working principle

Diagrammatic sketch of anti-abrasion beams and its working principle.

auxiliary power ratio are generally

In 2014, the average net coal consumption and auxiliary

of 87 typical CFB boilers were 343.8g/kWh and 7.8%. Among them, the average net coal

respectively 347.0g/kWh and

of 300MW CFB boilers were

and 7.5%.With the development of technology and design concept, the

ut 4%, which significantly


solids in surrounding furnace. The study

mass velocity and the

The main reason for serious abrasion in transition region is

In China, the effective means to deal with CFB boiler abrasion is to add active multi-stage

is showed in Fig 8, by setting projections on wall to block flow

from 8m/s to 3m/s or less

, significantly reduce the abrasion of furnace heating surface. This

in China in recent year, and the use of this technology ensures

000 hours and control heating surface abrasion to a

and its working principle.

Fig.7 Abrasing of CFB boilers after the accumulated 20000 hours operation and with the

4.2 Cyclone failures prevention

Cyclone is one of the key components of CFB boiler,

high-temperature solids from flue

high concentrations solids in furnace, realizing the

problems of cyclone are the low

target region (Figure 8).

(a) center cylinder

Fig.

Inefficiencies are mainly affected by the structure of cyclone

center cylinder. To deal with the problem of deviation

geometric center, double eccentric arrangement can be taken to further improve

efficiency. In the early time, CFB boiler use retractor to fix center cylinder,

is fixed. There is also no expansion gap and cylinder fatigue deformation is easier to occur.

general structure to fix center cylinder is free hanging fixation. New center cylinder often

whole cast, in order to improve its resistance to deformation and

thickness is more than 15mm, and its

(a)Structure of double eccentric arrangement; (b) Principle of free hanging fixation

Fig.9 Free hanging fixation and double eccentric arrangement of CFB boiler

Abrasing of CFB boilers after the accumulated 20000 hours operation and with the

anti-abrasion beams

Cyclone failures prevention

Cyclone is one of the key components of CFB boiler, its main role is to separate a large quantity of

flue gas and sent them back to the furnace, ensuring the fluidization of

high concentrations solids in furnace, realizing the multiple cycle of fuel and sorbent. The main

low efficiency; the center cylinder deformation and serious abrasion of

center cylinder deformation; (b)center cylinder expansion joint leakage

Fig.8 Typical problem for CFB boiler cyclone

mainly affected by the structure of cyclone. It is often retrofitted

deal with the problem of deviation between center of flow field and the cylinder

geometric center, double eccentric arrangement can be taken to further improve

efficiency. In the early time, CFB boiler use retractor to fix center cylinder, and the connecting portion

s also no expansion gap and cylinder fatigue deformation is easier to occur.

general structure to fix center cylinder is free hanging fixation. New center cylinder often

whole cast, in order to improve its resistance to deformation and extended service life

and its life can be increased to more than five years (Figure


Free hanging fixation and double eccentric arrangement of CFB boiler

Abrasing of CFB boilers after the accumulated 20000 hours operation and with the existing of

its main role is to separate a large quantity of

gas and sent them back to the furnace, ensuring the fluidization of

multiple cycle of fuel and sorbent. The main

deformation and serious abrasion of

expansion joint leakage

retrofitted by replacing the

center of flow field and the cylinder

geometric center, double eccentric arrangement can be taken to further improve the separation

the connecting portion

s also no expansion gap and cylinder fatigue deformation is easier to occur. Now, the

general structure to fix center cylinder is free hanging fixation. New center cylinder often be made by

extended service life.[12] The cylinder

life can be increased to more than five years (Figure 9).


Free hanging fixation and double eccentric arrangement of CFB boiler

Target area is the arc-shaped area toward imported flue, and it is the main zone where bear the impact

when high dust gas sharply rotates in cyclone. Due to high dust gas erosion, thermal shock caused by

and temperature gradients and partial high temperature; corrosion failure or deterioration failure caused

by sulfur, alkali metals, fine particulate penetration, wear-resisting and refractory materials in target

area is easily damaged.[13] To deal with target area abrasion, zirconium chromium carbide

wear-resistant corrosion-resistant plastic material can be used to transform generally (Figure 10).

(a) Target area abrasion; (b)effect of zirconium chromium carbide wear-resistant corrosion-resistant

plastic material refractory (three years later)

Fig.10 cyclone target area abrasion and eliminate

4.3 Nozzle button abrasion and slag leakage control

The design of CFB boiler must ensure that the air is uniform distribution over the entire cross section

of the furnace,. in order to make the bed material fluidized uniformly, prevent the slag leaking into the

air box, bed material coking. the air nozzles shown in Fig.11 were widely used in China: pigtail nozzle,

7-shaped nozzle, arrow-shaped nozzle, cylindrical nozzle; bell-shaped nozzle and so on. The main

problems of traditional nozzles are high resistance, serious abrasion, un-uniform fluidization and slag

leakage.[14]

(a) pigtail nozzle; (b)7-shaped nozzle; (c)arrow-shaped nozzle; (d)cylindrical nozzle; (e) bell-shaped

nozzle

Fig.11 typical type of CFB air nozzle

Fig.12 Abrasion of nozzle button

Nozzle abrasion is related with wind speed of nozzle outlet. When the wind speed increased by 15%,

abrasion rate increase 1.5 times. In addition, the air nozzles of early CFB boiler often blow each other,

which would result in serious abrasion and affect t

boiler has larger bed area. When the resistance of air nozzle is insufficient to overcome the fluctuations

of bed pressure, un-uniform fluidization and slag leakage would occur (Fig

To solve these problems, the most effective method is to replace all the air nozzles with new type.

Fig.14 shows the structure of the new type air nozzle us

fan power consumption, prevent slag leakage and prolong the life of air nozzles.

Fig.14 Structure schematic diagram of wear

4.4 Start fuel-saving

There are large quantity of wear

of bed material. When the boiler starts up, it is need to use oil to heat the bed material to a certain value

before adding coal. Early CFB boiler normally use the mechanical oil gun. Due to incomplete

combustion, ignition oil consu

atomization oil gun in China. Since the atomization condition is greatly improved,

higher-temperature flue gas can be got easily. Radiation intensity is significantly increased. Combined

with micro-fluidized ignition, the ignition oil consumption of 135MW CFB boiler burning anthracite is

about 6~8t/times, and 3~4t/times when burning lignite.

4.5 Transformation of coal screening system

It is generally believed that CFB boiler has a

has a high proportion of coarse particles and fine powder, lack

boiler would be prone to abnormal operation. Currently, China utilize high rescreening,

other newly screening devices.

function well when deal with high

an example, it replaces the original ‘static mesh’ to ‘moving mesh’, and set scraper under the axis of

sieve to keep it smooth, and the screening efficiency can be stabilized above 90% even mixed with coal

slime and lignite.


which would result in serious abrasion and affect the uniformity of wind (Fig.12). Large scale CFB


uniform fluidization and slag leakage would occur (Fig.13).

Fig.13 Slag leakage of nozzle button


shows the structure of the new type air nozzle used in China, which could reduce the primary

event slag leakage and prolong the life of air nozzles.[15]

Structure schematic diagram of wear-resistance slag leak-proof nozzle button

There are large quantity of wear-resistant material at CFB boiler dense region, as well as dozens of tons



combustion, ignition oil consumption is high. Now, it has been replaced by the new compressed air


temperature flue gas can be got easily. Radiation intensity is significantly increased. Combined

fluidized ignition, the ignition oil consumption of 135MW CFB boiler burning anthracite is

about 6~8t/times, and 3~4t/times when burning lignite.[16][17]

4.5 Transformation of coal screening system

It is generally believed that CFB boiler has a wide range of adaptability for different fuel, but if the coal

has a high proportion of coarse particles and fine powder, lacking of intermediate-sized particles, CFB

boiler would be prone to abnormal operation. Currently, China utilize high rescreening,

These devices have high reliability and environmental protection, even

deal with high-moisture readily clogging fuel. Take cross sieve showed in Fig

original ‘static mesh’ to ‘moving mesh’, and set scraper under the axis of

the screening efficiency can be stabilized above 90% even mixed with coal


). Large scale CFB



d in China, which could reduce the primary

proof nozzle button

well as dozens of tons



mption is high. Now, it has been replaced by the new compressed air


temperature flue gas can be got easily. Radiation intensity is significantly increased. Combined

fluidized ignition, the ignition oil consumption of 135MW CFB boiler burning anthracite is

wide range of adaptability for different fuel, but if the coal

sized particles, CFB

boiler would be prone to abnormal operation. Currently, China utilize high rescreening, crosssieve and

hese devices have high reliability and environmental protection, even

moisture readily clogging fuel. Take cross sieve showed in Fig.15 as

original ‘static mesh’ to ‘moving mesh’, and set scraper under the axis of

the screening efficiency can be stabilized above 90% even mixed with coal

Fig.15 Structure and schematic diagram of new cross sieve

4.6 Operation optimization

CFB boiler usually uses low-grade fuel,

incomplete combustion heat loss

for optimizing the operation is to improve

includes the cold test, thermal

calibration test, air-distribution

uniformity test and so on. Thermal test is the test after boiler operation

gas temperature field and oxygen calibration field calibration tests,

on. According to these experiment

combustion equipment. Combustion adjustment test can optimize the combustion state of boiler,

the relevant work can improve boiler efficiency of 0.5~1%

4.7 Pollutant emission control

During the development of CFB boiler in China, environmental emission standards have been upgrade

many times. The emission standards of

1000mg/Nm3 to 400mg/Nm3 and 450mg/Nm

200mg/Nm3, respectively, with

35mg/Nm3 and 50mg/Nm3, respectively

desulfurization efficiency of CFB boiler can reach above 90%

design. Along with the combustion optimization, CFB boiler can meet the emission standard of SO

and NOx of less than 200mg/Nm

countries. With the added SNCR

boilers have ability to meet more stringent environmental standards and

adaptability.[18][19]

Fig.1

4.8 The Foundation of technical

An important experience of China in the development of CFB boiler is to establish the technical system

of the industry. Through the establishment of technical standards, Chinese researchers accelerate the

Structure and schematic diagram of new cross sieve

grade fuel, and the corresponding physical heat loss and mechanical

incomplete combustion heat loss of cinder is larger. So there is large space to improve it.

is to improve the safety and economy of CFB boiler. The optimization

thermal test and combustion adjustment test. Cold tests include

distribution plate resistance test, critical fluidized air flow rate test, air distribution

uniformity test and so on. Thermal test is the test after boiler operation starts, which

gas temperature field and oxygen calibration field calibration tests, fuel tail air leakage rate test and so

these experiments, we can master the basic characteristic and discipline of

combustion equipment. Combustion adjustment test can optimize the combustion state of boiler,

ove boiler efficiency of 0.5~1% by experience.

Pollutant emission control


The emission standards of SO2 and NOx firstly declined from 2000mg/Nm

and 450mg/Nm3, respectively. And then they declined to 200mg/ Nm

with some areas even carrying out the ultra-low emissions standards

, respectively. The boiler operation results in China

desulfurization efficiency of CFB boiler can reach above 90% with rational furnace desulfurization

combustion optimization, CFB boiler can meet the emission standard of SO

ess than 200mg/Nm3 without any additional devices, which is attractive to developing

added SNCR denitration unit and outside-furnace desulfurization equipment, CFB

boilers have ability to meet more stringent environmental standards and stronger technical

Fig.16 Chang of SO2 and NOx emission standards

echnical system



corresponding physical heat loss and mechanical

improve it. The purpose

. The optimization

Cold tests includes air flow

test, air distribution

which includes exhaust

fuel tail air leakage rate test and so

, we can master the basic characteristic and discipline of

combustion equipment. Combustion adjustment test can optimize the combustion state of boiler, and


from 2000mg/Nm3 and

declined to 200mg/ Nm3 and

low emissions standards of

in China show that the

rational furnace desulfurization

combustion optimization, CFB boiler can meet the emission standard of SO2

without any additional devices, which is attractive to developing

furnace desulfurization equipment, CFB

stronger technical



introduction and application of new products and

the entire industry. At present, China has developed nearly 20 circulating fluidized bed boiler industry

standards and accumulated a lot of experience in design, manufacture and utilization, which plays an

important role in improving the operation level of CFB boiler in China

Tab.1 Current industry standard of circulating fluidized bed boiler in China

Standard types

Operation

standard

Guide for 135MW circulating fluidized bed boiler operation


Debugging and

test standard

Guide for circulating fluidized bed boiler start

Performance test code for circulating fluidized bed boiler

Guide of cold and combustion adjustment tests for

Design and

maintenance

standard

Guide of measuring points arrangement for circulating fluidized bed boilers

Technical condition of circulating fluidized bed boiler combustion system

Technical g

Construction

Guideline for maintenance of circulating fluidized bed boiler

Auxiliary

system standard

Guide on selection of coal preparation system for circulating

The technical requirements for rotary bottom ash cooler of

Technical requirements for fan of circulating fluidized bed boiler

In addition, Chinese researchers also pay great attention to

years, more than 20 kinds of academic books about CFB boiler have been published (Figure 1

of the popular books, such as Technology and engineering application of large circulating fluidized bed

boiler, 1000 questions about the circulating fluidized bed boiler technology and Large circulating

fluidized bed boiler technology can reach 20 thousand.

exchange service cooperation of CFB unit network, which is established in China, organizes the 2~3

meeting of the industry every year.

circulating fluidized bed power gene

important role in the development of China's CFB power generation technology.

Fig.17 Best-selling books of CFB power generation which published by China Electric Power Press

[Results]

The unique advantages of CFB boiler determine its rapid development in China. At present, it plays an

important role in the utilization of special fuels, such as Coal gangue, slurry, lignite, anthracite

biomass. Consequently it makes a remarkable contribut

application of new products and new technologies and promote the development of

At present, China has developed nearly 20 circulating fluidized bed boiler industry


portant role in improving the operation level of CFB boiler in China

1 Current industry standard of circulating fluidized bed boiler in China

Standard names


uide for 300MW circulating fluidized bed boiler operation

Guide for circulating fluidized bed boiler start-up and commissioning

Performance test code for circulating fluidized bed boiler

Guide of cold and combustion adjustment tests for CFB boilers



Technical guidance of CFB boiler refractory construction

Construction and quality acceptance criteria for CFB Boiler

Guideline for maintenance of circulating fluidized bed boiler

Guide on selection of coal preparation system for circulating fluidized bed boiler

The technical requirements for rotary bottom ash cooler of CFB


In addition, Chinese researchers also pay great attention to summarizing technology.

kinds of academic books about CFB boiler have been published (Figure 1

such as Technology and engineering application of large circulating fluidized bed


fluidized bed boiler technology can reach 20 thousand. National electric power industry technical


meeting of the industry every year. China circulating fluidized bed power generation (magazine),

circulating fluidized bed power generation (WeChat Subscription) founded by it

important role in the development of China's CFB power generation technology.

selling books of CFB power generation which published by China Electric Power Press

unique advantages of CFB boiler determine its rapid development in China. At present, it plays an

important role in the utilization of special fuels, such as Coal gangue, slurry, lignite, anthracite

biomass. Consequently it makes a remarkable contribution to optimizing the power structure of China,

new technologies and promote the development of

At present, China has developed nearly 20 circulating fluidized bed boiler industry


1 Current industry standard of circulating fluidized bed boiler in China

up and commissioning



fluidized bed boiler

boilers


technology. In the past ten

kinds of academic books about CFB boiler have been published (Figure 17). Sales

such as Technology and engineering application of large circulating fluidized bed


ower industry technical


China circulating fluidized bed power generation (magazine),

ration (WeChat Subscription) founded by it also plays an

selling books of CFB power generation which published by China Electric Power Press

unique advantages of CFB boiler determine its rapid development in China. At present, it plays an

important role in the utilization of special fuels, such as Coal gangue, slurry, lignite, anthracite and

ion to optimizing the power structure of China,

improving the utilization efficiency of the whole resource and reducing the emission of pollutants.

CFB boiler mainly uses inferior fuel with low calorific value, so it’s flow characteristics, combustion

process and heat transfer characteristics are quite different from the conventional pulverized coal boiler.

Therefore, in the early stage of production, there are plenty of problems in the design, operation, repair

and maintenance process. These problems have certain influence on the index of reliability, economy

and environmental protection. Recently years, with the continuous hard work from the technicians, the

reliability, economy and environmental protection show tremendous improvement.

The application of the technologies of wear prevention and control of heating surface in furnace,

cyclone separator fault prevention, wear and leakage treatment for air button, oil saving at start-up,

transformation of coal sieving system, operational optimization and adjustment and pollutant emission

control is conducive to further improve the development level of CFB boiler technology.

[Conclusions]

There are rich coal resources in the Asia Pacific region, but the proportion of inferior coal is very large.

Many countries with underdeveloped economy need to develop their own infrastructure, enhance

national strength and improve people's livelihood, so as to provide more space for the CFB bed power

market. CFB power generation with the advantages of high efficiency, energy saving and

environmental protection is suitable for these countries, and the new construction of large-scale CFB

units is particularly urgent.

China has accumulated rich experiences in the design, manufacture, installation and maintenance

management of CFB boiler, and plays an important role in the sustainable development of CFB boiler

technology. The characteristics of resource environment and energy structure in the Asia Pacific region

are similar to China, and China's experiences are worth promoting.

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[Acknowledgements]

This work was supported by Chinese Society for Electrical Engineering Young Talent Assistance

Project (JLB2016059) and Beijing Talent Training Project (2014000102592G308).

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