Homemade Calcium Silicate Board?

[brickie in oz]

Thinking outside of the square again.....
Has anyone made or considered making there own Calcium Silicate board?

I did a google and it seems its made from limestone, with all the know how on this forum Im sure we can work it out.

[Gulf]

The fillers and binders (some form of lime etc.) would probably be easy to obtain. Finding a cheap source of silicate fiber would probably be the kicker though. But, if it could be done then casting a more efficent insulation barrier around the dome would be a great.

[GianniFocaccia]

INSWOOL Bulk products can be hammer-milled for vacuum forming applications in manufacturing boards or shapes.

I found this on the Harbison-Walker website (anhrefractories.com) under Ceramic Fiber. It is an alumina silicate bulk product that can be formed into boards and shapes in a vacuum. I wonder if cal-sil boards are made the same way.
John

[C5dad]

I thought that the insulation in ovens was cal-sil boards. Just round up a few old ovens and you should have enough I would think. Anybody else hear of this?

[david s]

Originally Posted by brickie in oz

Thinking outside of the square again.....
Has anyone made or considered making there own Calcium Silicate board?

I did a google and it seems its made from limestone, with all the know how on this forum Im sure we can work it out.

Portland cement is made from calcium silicate, but I think it is in a different form because cement is very dense and the board is not. If cal. Sil. Board is made in Australia you might be able to visit where they make it to work out how to do it.
Share with us if you do.

[shuboyje]

I did a little reading and ran across an article that says insulator's are trained in fabricating cal-sil during their apprenticeship. I work with heat and front insulators daily, and know them pretty well, I'll ask about it next week.

[david s]

Excellent, this is the forum at its best. Hope you have luck.

[Gulf]

Originally Posted by shuboyje

I did a little reading and ran across an article that says insulator's are trained in fabricating cal-sil during their apprenticeship. I work with heat and front insulators daily, and know them pretty well, I'll ask about it next week.

The insulators where I work "install" a lot of CalSil. They install flat board under boilers, precast for different size piping, elbows etc. They "fabricate" specialized joints from precast stock to fit the situation. All of this is what I assume. Monday, I too will pick the brains of the Insulators where I work on what they know about fabricating CalSil.

[Johnny the oven man]

Cal>sil is 220kg/m3 density. The lighter grades of ins. castable are about 350-400kg/m3, so with the addition of some Vermiculite or perlite you could make up a very similiar brew using ready made mix.

[vtsteve]

Googled: calcium silicate/ production

From a factory proposal in Ethiopia:

Burnt lime is treated with hydrochloric acid to produce calcium chloride. The addition of acid should be so calculated and adjusted that almost a neutral solution is obtained. The clear solution of calcium chloride is decanted from the top.... The calcium chloride solution is then treated with a clear sodium silicate, [and] calcium silicate is precipitated out. The precipitate is centrifuged, washed, dried and packed in suitable containers.


Further processing (press? autoclave?) is needed to produce sheets.

From a UK report:

Calcium silicate bricks

Calcium silicate bricks are composed of a mixture of lime and sand (sand lime) or lime and siliceous gravel or rock (flint lime). The sand, gravel or rock is usually quarried from deposits adjacent to the works. The lime is usually bought in 'quick'. The quick lime is crushed and mixed with the sand or other material. The mixture is left in silos to hydrate and the slaked mix is pressed into bricks. The 'green' bricks are transferred to autoclaves [200 C and 8-16 bar] where they are hardened by the chemical action induced by the application of live steam under pressure.

It looks like the autoclave is the tough part.