Message-ID: <00998CF2.C6403000.20@bigvax.alfred.edu> Date: Thu, 2 Nov 1995 21:29:37 EST From: "William J. Walker, Jr." <mailto:walkerw@BIGVAX.ALFRED.EDU> Subject: Re: Earthquake-resistant housing design To: Multiple recipients of list DEVEL-L <mailto:DEVEL-L@AMERICAN.EDU>
To: MX%"mailto:DEVEL-L@AMERICAN.EDU"On Sun, 29 Oct 1995, Patrick L. Pierquet wrote:
>
> Also, does anyone know where I can purchase some "rice-husk ash"? It is said to
> be an environmentally-friendly substitute for portland cement. I'd like to do
> some experimentation with this material.
>
Vegatable ash falls into two catagories, those high in silica and those high in calcium. Rice hull ash is of the high in silica group, containing 90 to 97% silica. When combusted in the temperature range of 550 to 750C the silica is of a highly reactive amorphous form. This has been successfully used to make cement by blending it with lime or portland cement. The silica reacts with the lime to form calcium silicate hydrates - the compounds that make cement do its job.A good article is: A.A. Boateng and D.A. Skeete, 'Incineration of Rice Hull for Use as a Cementous Material: The Guyana Experience,' Cement and Concrete Research, vol 20, no 5, pp795-802, 1990.
Bill Walker mailto:walkerw@bigvax.alfred.edu NYS College of Ceramics at Alfred University Alfred NY