I use the ceramic fiber blanket for boiler refractory, and also in furnaces, the brand of ceramic fiber wool (cerawool),one of the brands, I use is made by AP green, Narco, Harbison, Walker.
You ask how long it will last, well it could last forever, but this statement needs some clarification, the fiber wool is like fiber glass it will not rot, it can withstand very high temperature, but you can also melt it with your torch (just as you can melt fiberglass or regular glass,now this does not mean it will melt right away if you have the yellow cooler part of your torch flame playing on the blanket, but if you focused the hotter blue part of your torch on the ceramic fiber wool you can melt the glass, this is Good stuff, how long it will last depends on how you use it, it could last you your lifetime or you can burn holes in it.
The ceramic fiber wool is a good insulator refractory, where you need a light weight insulation that will slow the convection of heat, (carry heat from one side to the other), the air in the fibers also helps, in some applications the fiber wool can be coated with a wash coat of slip type refractory like Sairset mortar, if you have a place that needs a harder silica surface coating, but in this thin application of the Sairset silica coating when dry would crack easily if the wall or the ceramic blanket was moved, or disturbed, in applications like where it needs a little more strength a castable refractory would be used with a wash coat of Sairset fire-clay, other areas like around a burner we would use fire brick which can also have a wash coat if needed, not all fire brick is equal, the light weight brick will not conduct heat as easily as the tougher dense hard type of a fire brick, there are several types of refractory material each will have a certain application in a boiler or furnace.
Not sure if this answers your question.
