Power Industry Refractory

The working environment of CFB boiler is high speed fluidized particles abrasion and impact, chemical reaction and corrosion, frequent thermal exchange. So CFB boiler lining refractory have high mechanical strength, excellent abrasion resistance, good corrosion resistance, good thermal shock resistance and so on.

Refractories Conformation Scheme for CFB Boiler

Refractories for CFB Boiler System

Boiler Combustion Chamber

RSNM-B Castables(Dense phase zone, sparse phase zone, boiler roof and etc.)RSNMKS Plastic Castables(Fluidized section of dense phase zone)

Air Separation

RSNM-A Castables or RSNM-75 Wear-resistant Bricks(Used on straight part and cone-shaped part of cyclone tube , gateway, refeeder etc.)

Economizer

RSZGN-42 Refractory Bricks
RSNM-75 Wear-resistant Bricks
RSNM-A Dense Castables
RSQZ -0.7 Light Weight Castables
RSQZ -0.3/0.6 Light Weight Insulating Products
RSNT-2 Castables(Beam of economizer)
RSXWT-100 Refractory Fiber Blanket

Ignition Air Flue、Cold Air Chamber

RSJZL -1 Castables
RSNT-2 Castables

The Tail Flue

RSNM-B Castables
RSQZBW -650/1000 Light Weight Insulating Products
RSZGN-42 Refractory Bricks

Unshaped Refractory Materials

Unshaped refractory is most important refractory used in CFB boiler, it accounts for 70%~80% of the total amount. Low cement castable, ultra low cement abrasion resistant castable and no cement wearing resistant castable are usually used in circulating fluidized bed boiler.

Wear-resistant Castables

The wear resistant castables, made from fused corundum, super grade bauxite, sillimanite, alumina powder and silicon powder as raw materials, are featured with convenient construction, good wear esistance, good spalling resistance, and high strength at early and mid-high temperature period, which overcome the disadvantages of traditional castables.

Item		Specification
Bulk Density, g/cm³	110℃ ×24h	≥2.75
Permanent Linear Change On Heating , %	1100℃ ×3h	±0.4
CCS , MPa	110℃ ×24h	≥100
CCS , MPa	1100℃ ×3h	≥120
CMOR , MPa	110℃ ×24h	≥10
CMOR , MPa	1100℃ ×3h	≥18
Thermal Shock Resistance，Cycle	1000℃ Water Quenching	≥20
Thermal Shock Resistance， Cycle	ASTM C-704	＜6
Wear-resistance Index, cc	Al₂O₃	≥75
Wear-resistance Index, cc	SiO₂	＜18
Maximum Service Temperature,℃		1600
Service Area	Dense phase area and transition area of combustion chamber, furnace bottom, cyclone cylinder outlet mixing chamber.

Steel Fiber Reinforced Wear-resistant Castables

The castables are produced by adding some silicon carbide, mullite, and steel fiber to enhance the tensile property, strength, and thermal shock resistance on the basis of the technology of optimized wear resistance castables. It is used in cutting direction entrance of cyclone separator and “target area” on the cartridge of circulating fluidized bed boiler, which are the worst wear parts.

Brand		Bulk Density, g/cm³
Item		Specification
Permanent Linear Change On Heating, %	110℃ ×24h	≥2.8
CCS, MPa	1100℃ ×3h	±0.4
MOR, MPa	110℃ ×24h	≥100
MOR, MPa	1100℃ ×3h	≥120
Thermal Shock Resistance， Cycle	110℃ ×24h	≥17
Thermal Shock Resistance， Cycle	1100℃ ×3h	≥20
Wear-resistance Index, cc	1000℃ Water Quenching	≥25
Horizontal flue at furnace outlet, straight part and cone-shaped part of separator,entry and exit, refeeder and dipleg etc.	ASTM C-704	≤5
Chemical Composition,%	Al₂O₃	≥80
Chemical Composition,%	SiO₂	＜11
Maximum Service Temperature,℃		1600
Service Area	Horizontal flue at furnace outlet, straight part and cone-shaped part of separator, entry and exit, refeeder and dipleg etc.

Wear-resistant Plastic Refractories

Compared with traditional refractory plastic, the wear-resistant plastic refractories are featured with good plastic ability, long shelf life, high strength,h and good wear resistance. The strength of the material increases with increasing temperature due to the adoption of composite binder. The wear-resistant plastic refractories, using fused corundum, mullite,e and super grade bauxite as main raw materials, the addition of Guangxi white clay ensures that the refractory plastic can have high plasticity, enhance the crushing strength and wear resistance, especially suitable for repairing CFB boilers and the overall construction of wear-resistant lining. Refractory plastic can be processed into non-baking materials, then the furnace can be started directly start if necessary.

Brand		RSNMKS-A
Item		Specification
CCS, MPa	110℃ ×24h	≥2.7
MOR, MPa	110℃ ×24h	≥80
MOR, MPa	1100℃ ×3h	≥100
MOR , MPa	110℃ ×24h	≥12
MOR , MPa	1100℃ ×3h	≥14
Chemical Composition, %	Maximum Service Temperature, ℃	≥80
Wear resistant parts, such as dense phase area, overheating screen, separator target area, horizontal flue etc.		1600
Wear-resistance Index,cc	ASTM C-704	≤6
Service Area	Wear resistant parts, such as dense phase area, overheating screen, separator target area, horizontal flue, etc.

Thermal Shock Resistant Castables

Most CFB furnaces are ignited under the bed. The ignition temperature is high, and the temperature rises rapidly after ignition. The oil gun will be turned off after the boiler reaches 650 degrees, and the temperature will drop to 150 degrees instantaneously. Therefore, thermal shock resistance and high refractoriness are required, especially in the air chamber, igniter, and water-cooled air chamber. Thermal shock resistant castable is the best choice for these areas.

Brand		RSKRZ-1
Item		Specification
Bulk Density，g/cm³	110℃ ×24h	≥2.8
Igniter, ignition air flow, water cooling chamber	110℃ ×24h	≥100
Igniter, ignition air flow, water cooling chamber	1100℃ ×3h	≥120
MOR， MPa	110℃ ×24h	≥17
MOR， MPa	1100℃ ×3h	≥20
Thermal Shock Resistance， Cycle	1000℃ Water Quenching	≥25
Maximum Service Temperature，℃		1600
Service Area	Igniter, ignition air flue, water cooling chamber

Fireclay Castables

Brand		RSNTJ-2
Item		Specification
Bulk Density，g/cm³	110℃ ×24h	2.2-2.4
CCS，MPa	110℃ ×24h	≥40
CCS，MPa	1100℃ ×3h	≥50
CCS， MPa	110℃ ×24h	≥5
CCS， MPa	1100℃ ×3h	≥6
MOR， MPa	1000℃ Water Quenching	≥20
Maximum Service Temperature，℃		1400
Service Area	Ignition duct, mixing chamber, coal economizer beam