Electric power industry

Working medium of CFB boiler – this is high speed fluidized particle abrasion and impact, chemical reactions and corrosion, frequent heat exchange. Thus, refractory lining of the CFB boiler has high mechanical strength, excellent abrasion resistance, good corrosion resistance, good resistance to thermal shock and so on.

Layout diagram of refractories for a CFB boiler

Refractories for the CFB boiler system

Boiler combustion chamber

RSNM-B Castables(Dense phase zone, rarefied phase zone, boiler roof, etc. d.) RSNMKS Plastic castings(Fluidized section of the dense phase zone)

Air separation

RSNM-A Castables or RSNM-75Wear Resistant Bricks(Used on straight pants and cone shaped part of cyclone pipe, gateway, dispensers etc.)

economizer

RSZGN-42 fire brick
RSNM-75 Wear-resistant brick
RSNM-A Dense castings
RSQZ -0.7 Lightweight castings
RSQZ -0.3/0.6 Lightweight insulating products
RSNT-2 Castables(Economizer beam)
RSXWT-100 Fire Retardant Fiber Blanket

Chimney for air ignition, Cold air chamber

RSJZL -1 Castables
RSNT-2 Castables

The Tail Flue

RSNM-B Castables
RSQZBW -650/1000 Lightweight insulating products
RSZGN-42 fire brick

Unshaped refractory materials

Unshaped refractory is the most important refractory, used in CFB boilers, it accounts for 70–80% of the total. Circulating fluidized bed boilers typically use casting materials with low cement content, concrete products with ultra-low cement content, abrasion resistant, as well as concrete products, wear-resistant without cement.

Wear-resistant Castable

Wear-resistant Castable, made from fused corundum, premium grade bauxite, sillimanite, aluminum oxide and silicon powder as raw materials, they have a convenient design, good wear resistance, good resistance to chipping and high strength during early and medium-high temperatures, which allows you to overcome the disadvantages of traditional casting products.

Subject		Specification
Bulk density, g/cm³	110℃ ×24h	≥2.75
Constant linear change with 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
Wear resistance index, cc	ASTM C-704	＜6
Chemical composition , %	Al₂O₃	≥75
Chemical composition , %	SiO₂	＜18
Maximum operating temperature,℃		1600
Service zone	Dense phase zone and transition zone of the combustion chamber, oven bottom, mixing chambers at the outlet of the cyclone cylinder.

Wear-resistant castings, steel fiber reinforced

Castings are produced by adding silicon carbide, mullite and steel fiber to improve tensile properties, strength and heat resistance based on optimized wear-resistant casting technology. It is used in the inlet to the cutting direction of the cyclone separator and in the "target zone" of the circulating fluidized bed boiler cartridge, which are the most worn parts.

Brand		RSNM-A
Subject		Specification
Bulk density , g/cm³	110℃ ×24h	≥2.8
Constant linear change with heating, %	1100℃ ×3h	±0.4
CCS , MPa	110℃ ×24h	≥100
CCS , MPa	1100℃ ×3h	≥120
MOR , MPa	110℃ ×24h	≥17
MOR , MPa	1100℃ ×3h	≥20
Thermal shock resistance, cycle	1000℃ Water Quenching	≥25
Wear resistance index, cc	ASTM C-704	≤5
Chemical composition,%	Al₂O₃	≥80
Chemical composition,%	SiO₂	＜11
Maximum operating temperature,℃		1600
Service zone	Horizontal chimney at the outlet of the furnace, straight part and cone-shaped part of the separator, entry and exit, dispenser and dipleg, etc..

Wear-resistant plastic refractories

Compared with traditional fireproof plastic, wear-resistant plastic refractories have good ductility, long shelf life, high strength and good wear resistance. The strength of the material increases with increasing temperature due to the use of a composite binder. Wear-resistant plastic refractories, using fused corundum as the main raw material, mullite and bauxite of the highest grade, with the addition of Guangxi white clay guarantee, that fire-resistant plastic can have high ductility, improve crushing strength and wear resistance, Particularly suitable for repair of CFB boilers and general wear-resistant lining design. Fireproof plastic can be recycled into materials, unsuitable for baking, after which, if necessary, you can directly start the oven.

Brand		RSNMKS-A
Subject		Specification
Bulk density , g/cm³	110℃ ×24h	≥2.7
CCS , MPa	110℃ ×24h	≥80
CCS , MPa	1100℃ ×3h	≥100
MOR , MPa	110℃ ×24h	≥12
MOR , MPa	1100℃ ×3h	≥14
Chemical composition, %	Al₂O₃	≥80
Maximum operating temperature , ℃		1600
Wear resistance index, cc	ASTM C-704	≤6
Service zone	Wear parts, such as dense phase zone, overheating screen, separator target zone, horizontal chimney, etc..

Thermal shock resistant castings

Most CFB stoves fire under a bed, ignition temperature is high, and the temperature rises quickly after ignition; The oil gun will be turned off after, how the boiler reaches 650 degrees, and the temperature will instantly drop to 150 degrees. Hence, thermal shock resistance and high fire resistance are required, especially in the air chamber, igniter and water-cooled air chamber. Injection mold, thermal shock resistant, is the best choice for these areas.

Brand		RSKRZ-1
Subject		Specification
Bulk density，g/cm³	110℃ ×24h	≥2.8
CCS，MPa	110℃ ×24h	≥100
CCS，MPa	1100℃ ×3h	≥120
MOR，MPa	110℃ ×24h	≥17
MOR，MPa	1100℃ ×3h	≥20
Thermal shock resistance，Cycle	1000℃ Water Quenching	≥25
Maximum operating temperature，℃		1600
Service zone	Igniter, air duct for ignition, water cooling chamber

Products for casting from fireclay clay

Brand		RSNTJ-2
Subject		Specification
Bulk density，g/cm³	110℃ ×24h	2.2-2.4
CCS，MPa	110℃ ×24h	≥40
CCS，MPa	1100℃ ×3h	≥50
MOR，MPa	110℃ ×24h	≥5
MOR，MPa	1100℃ ×3h	≥6
Thermal shock resistance, cycle	1000 ℃ Water quenching	≥20
Maximum operating temperature，℃		1400
Service zone	Ignition channel, mixing chamber, coal economizer beam