Product Description

General situation of wet desulfurization of chimney
Sulfur dioxide emissions is the main cause of air pollution and acid rain in China rising, sulfur dioxide emissions from coal-fired power plants accounted for about 50%. of the sulfur dioxide emissions in recent years, the state has adopted a series of measures to vigorously promote the construction of thermal power plant flue gas desulfurization project. The main use of foreign mature applications, widely used (wet limestone / gypsum method) desulfurization process. After flue gas wet desulfurization, humidity increases, the decrease of temperature, easily in the condensation inside the chimney, flue gas residual three sulfur dioxide dissolved, dilute sulfuric acid solution to form a strong corrosive corrosion situation further. The flue gas desulfurization has the following characteristics:

The flue gas humidity, in wet flue gas saturated with the corrosive medium in the dual role of flue gas pressure and humidity, the chimney inside structure density of poor materials are susceptible to corrosion, affect the durability of the structure.Dilute sulfuric acid solution with lower concentration is more corrosive than acid solution with high concentration.

When the temperature of the acid solution is 40 degrees ~80 degrees centigrade, the corrosion resistance of the structural material is especially strong. Taking steel products as an example, the corrosion rate at the temperature of 40 degrees ~80 DEG C is about 3~8 times higher than that at other temperatures.

The flue gas after wet desulfurization usually contains strong corrosive substances such as hydrogen fluoride and chloride. It is a kind of low temperature, high humidity and dilute acid corrosion condition with high corrosion strength, high permeability and difficult to be prevented.

In the actual operation conditions, the acid liquid along the inner wall of chimney gap to the chimney wall permeability and corrosion, resulting in serious hidden trouble to the safe operation of the chimney. The chimney wet desulfurization condensation liquid pH value is about 2, the smoke corrosive as “high” chemical corrosion grade, strong corrosive grade.

 
Product features
1. Super acid resistance
Silicone materials have acid resistance and dilute alkaline aqueous solution ability. Usually, adding filler with excellent acid resistance and silane coupling agent to silicone rubber could improve its acid resistance to a certain extent. Our company adopts special process to filler, makes a joint connection between silicon and filler to improve the acid resistance of chimney rubber.
2. Excellent heat resistance
During the process of discharging smoke by the chimney in the power plant, due to the changes of working condition, the smoke temperature would be 40~150℃, in accident condition, it would be over 180℃ or even higher, which requires chimney anti-corrosion rubber with excellent heat resistance. Because of silicone rubber’s main chain is composed of silicon-oxygen bond, it has good thermal oxidation stability. Its other mechanical performance would not change under 150℃, and its shelf life could be over 1000 hours under 200℃. We adopt heat resistant filler to make the chimney has better heat resistance. As anti-corrosion material, the product could completely meet the requirement of working temperature in the chimney.
3. Excellent weather resistance
There is no unsaturated bond in the main chain of silicone rubber, and silicon-oxygen bond is stable to oxygen, ozone and ultraviolet.Outdoor exposure and accelerated aging tests show that there is no aging phenomenon of cracking, degradation or tacky after exposed in UV and rain for a long time (over 20 years).

 

 

Key performance indicators of KDW-116

Number	Item	Units of measurement	Performance	Test method
1	Adhesive strength(coating to steel) (coating to adhesive)	Mpa	≥1	GB/T 16777
2	Temperature resistance	℃	≥180	GB/T 16777
3	Completely curing time	h	≤4.0	GB/T 16777

 

Using method
1. Clean the surface:
Clean the surface of chimney inner wall as general surface, remove dust and greasy dirt.
2. Sizing:
Take the prime coating out of the package, spray it on the surface of chimney inner wall with professional spraying tools, and just dried at room temperature.

http://cloud.video.taobao.com/play/u/984094043/p/1/e/1/t/1/54895189.swf

Packing & storage:
1. Packing: 10KG/iron drum
2. Storage:
Stored in sealed containers, the temperature should not be higher than 28℃, and the shelf life would be 9 months in sealed at 23~25℃.

 

Key performance indicators of KDW-982

Item		Unused		Used	Test method
		A	B
Uncured	Appearance & color	White/gray paste	Black paste	Black paste	Visual
	Density(g/cm3)	1.3~1.5	1.08	1.3~1.5	GB/T13477.2
Operation time(h)		1~2			–
Curing time(25℃, h)		24~48			–
Cured	Tensile strength(Mpa)	≥2.0			GBT/528 Dumbbell I type, 500mm/min
	Elongation(%)	≥100			GBT/528 Dumbbell I type, 500mm/min
	Shore hardness(A)	40~60			GBT/531
	Shear strength(Mpa)	≥1.5			GBT/7124 5mm/min, steel to steel
	50℃, 5% vitriol soak for 7 days(%)	No significant change on appearance, retention rate of tensile strength ≥80			GBT/528 Dumbbell I type, 500mm/min
	Heat resistance(180℃, 24h)	No significant change on appearance, retention rate of tensile strength ≥90			GBT/528 Dumbbell I type, 500mm/min
	80℃, 7 days, acid corrosion resistance to the mixture composed of 2% vitriol, 0.1% hydrochloric acid, 0.1% nitric acid and 0.1% phosphoric acid(%)	No significant change on appearance, retention rate of tensile strength ≥65			GBT/528 Dumbbell I type, 500mm/min
	Adhesive strength(steel to steel) (Mpa)	≥1.0			GB/T50212

 

Using method
1. Mix rubber
The recommended ratio is 10:1(component A: component B), and the operation time would be 1 hour when the operation temperature is 25℃. Increasing or decreasing the amount of component B within ±15% to speed up or slow down the curing speed.
2. Stir
Completely stir the rubber with electric tool or other stirrer, the mixed rubber should be black, if it is white or too shallow, or local color is too deep, it is needed to stir until evenly colored.
3. Paste
Evenly smear the mixed chimney anti-corrosion rubber on foam glass bricks or light vitreous tiles, ensure that the thickness of rubber between bricks and chimney inner wall is not less than 3mm and the thickness between bricks is not less than 1mm.

 

Notes:
1. The product should only be used after evenly mixing component A & B according to appropriate ratio. If not mixing evenly or the ratio is not recommended, whether it could meet the construction requirements would not be guaranteed.
2. Curing speed is affected by the operation temperature, the higher the temperature, the fast the curing.

 

 

Packing & Storage:
1. Packing
Component A: drum, 25KG/drum
Component B: Soft packing, 0.4KG/branch; plastic tube, 0.33KG/branch
2. Storage & shelf life
Both component A & B should be stored in sealed containers, and the temperature should not higher than 28℃. The shelf life would be 9 months in sealed condition at 23~25℃.

 

 

Key performance indicators of KDW-987

Item		Performance	Test methods
Uncured	Appearance & color	Black paste	Visual
	Density(g/cm3)	1.2~1.4	GB/T13477.2
	Tack free time(min)	10~30	Touch method
Cured	Tensile strength(Mpa)	≥2.0	GB/T 528 Dumbbell I type, 500mm/min
	Elongation(%)	≥200	GB/T 528 Dumbbell I type, 500mm/min
	Shore hardness(A)	30~50	GB/T 531
	Shear strength(Mpa)	≥1.5	GB/T 7124 5mm/min, steel to steel
	80℃, 20% vitriol soak for 7 days(%)	No significant change on appearance, retention rate of tensile strength ≥65	GB/T 528 Dumbbell I type, 500mm/min
	Heat resistance(180℃, 48h)	No significant change on appearance, retention rate of tensile strength ≥90	GB/T 528 Dumbbell I type, 500mm/min
	80℃, 14 days, acid corrosion resistance to the mixture composed of 2% vitriol, 0.1% hydrochloric acid, 0.1% nitric acid and 0.1% phosphoric acid(%)	No significant change on appearance, retention rate of tensile strength ≥70	GB/T 528 Dumbbell I type, 500mm/min
	Adhesive strength(steel to steel) (Mpa)	≥1.0	GB/T 50212

 

Using method

1. Clean the surface
Clean the surface of chimney inner wall as general surface, remove dust and greasy dirt.
2. Sizing
Take the rubber out of package, smear smoothly the rubber on the surface of chimney inner wall with professional tools, let it cured at room temperature.
3. Cure
The product is cured at room temperature, and it is solidified into elastomer by absorbing moisture in the air, whether completely cured depends on the thickness. (2~3mm thickness, at 25℃, humidity of 50%, it could be completely cured within 24 hours)

 

Notes:

After operation, please seal the unused rubber immediately. When using again, if there is a little crust on the sealing, just remove it, it would not affect the normal use.

 

Packing & Storage:

1. Packing: 25KG/plastic drum
2. Storage & shelf life:
Stored in the sealed containers, the temperature should not be higher than 28℃, and the shelf life would be 9 months in sealed at 23~25℃.

 

 

Analysis