9/22/2017 3:45:51 AM
Bio soluble ceramic fiber is manufactured from Alkaline Earth Silicate composition fibers (AES fiber). The main composition of bio soluble ceramic fiber is SiO2, CaO and MgO. Compared with the ceramic fiber, it could be biodegradable in body fluids and reducing the harm to human health. It is called as bio soluble fiber.
The bio soluble fiber is used to replace refractory ceramic fiber (RCF) in developed market. It is used to made textiles, blankets, modules, boards and shapes, filling materials and other high temperature insulation materials.
What is Bio soluble fiber?
The bio soluble fiber is a biodegradable fiber; it is manufactured to replace the ceramic fiber on high temperature insulation. It is made from Alkaline Earth Silicate (AES) fiber, the main composition is SiO2, CaO and MgO.
Based its biodegradability, it could be exhausted from lung even if a human inhale it in the body. So this could significantly reduce the risk of cancer in the human body.
At the same time, the bio soluble fiber has the same physical structure with ceramic fiber; this could make it perform very well in high temperature insulation environment. And the main composition of bio soluble fiber is SiO2, CaO and MgO; this could ensure it has high temperature performance.
In general, the bio soluble fiber is a high temperature insulation fiber which has biodegradability.
The features of Bio soluble fiber
Bio soluble fiber is virtually immune to thermal shock
The bio soluble fibers are opaque to infra-red and so maintain their low thermal conductivity to high temperature
The bio soluble fibers absorb very little energy on heating
The bio soluble fibers are high purity and non-corrosive
The bio soluble fibers are resilient and also resistant to mechanical damage
Exonerated from any carcinogenic classification under nota Q of directive 97/69 EC
Exonerated from any use restriction under annexed V number 7.1 of the German hazardous substances regulation
Lower thermal conductivity, improves insulation by 20% compared to other tested AES fibers
Up to 30% more fibers due to high fibre index, efficient prevention of heat transfer and greater strength
Improved handling, operator satisfaction
Where does Bio soluble fiber come from?
History shows that fine asbestos fibers inhaled into the lungs may cause cancer. Although the ceramic fiber is not asbestos, ceramic fiber has a higher persistence than most glass wools and mineral wools. This long term persistence will cause cancer potentially. Human epidemiology has shown that the reduction in lung function among smokers exposed to ceramic fiber.
In 1986 a study of all Man-Made Vitreous Fibers’ (MMVF) was initiated at the Research and Consulting Company (RCC) laboratory in Geneva.
Findings for refractory ceramic fiber were:
Fibrosis and increased tumor rate at maximum dose in rats
Increased mesothelioma (This is the origin of the EU classification of RCF) in hamsters.
In 1987, a company in England found that the persistence is a key determinant for an insulation material to be a health hazard. Then they invented the new bio soluble fiber is proved by various European labs which have since demonstrated the biodegradability (less than 10 days). This is the embryonic form of bio soluble fiber. The scientists take another 5 years to increase its high temperature insulation performance and production cost.
The refractory ceramic fiber was classified by EU in 1997 as carcinogen 2 following a full review of available test data on animals (97/69/EC). And this new EU regulation came into force on the 1st of June 2007. Under REACH carcinogen 2 becomes ―1B. One unanimous recommendation given by all regulators is to look for alternatives to refractory ceramic fiber.
These fibers may be exonerated from classification as a carcinogen if one of the specific criteria described under nota Q of Directive 97/69/EC are met.
The animal tests at RCC which lead to the classification of RCF also included X607; however animals exposed to X607 did not develop excess tumors. This fulfils the exoneration criteria under Nota Q.
The bio soluble fibers have shown <40 days half-life in IT tests on rats which also provides complete exoneration under Nota Q.
This is the brief process of the development of bio soluble fiber.
The production process of Bio soluble fiber
In fact, several companies in EU and USA hold the patent of bio soluble fiber production. The key point is that the content of Alkali metal oxide CaO & MgO could affect the biodegradability, but increase the difficulty of spinning and decrease the high temperature performance. How to control the content of Alkali metal oxide CaO & MgO embarrassed most factories.
On the other hand, the production process of bio soluble fiber is nearly the same with ceramic fiber.
How is the Bio soluble fiber used?
The bio soluble fiber textiles are made of spinning yarns which are reinforced filaments. Same with the ceramic fiber textiles, the bio soluble fiber is spine to the yarn. Then the bio soluble fiber yarn could be used to weave the bio soluble fiber cloth and bio soluble fiber tape, or braided to the bio soluble fiber ropes.
The bio soluble fiber blankets are made of needle fibers. According to the insulation theory, the density of blanket achieves 128kg/m3 could get the best high temperature insulation performance. So normally the density of the blankets is around 128kg/m3. After technology development, the bio soluble fiber blankets could save 20% more energy than ceramic fiber blankets.
Technical data of Bio soluble fiber
Composition: SiO2 55~70%, Cao+MgO 28~45%
Fiber diameter: 2~6μm
Fiber length: 50~150mm
Heat shrinkage rate (1232℃, 24h): 3.5%
Thermal Conductivity (538℃, 8pcf): 0.130w/m•k