Re: GBlist: toilets

Norbert Senf (
Tue, 11 Feb 1997 19:33:12 -0400

Ron Sutcliffe wrote:
> centralized articulated urban sewage treatment or the rural septic
> tank/absorption systems. Composting toilets can be a viable option,
> even on a permitted level as long as the public health/pathogen issue is
> adequately addressed.
> It is our belief that many composting toilets throughout the US do not
> adequately pasteurize the end product. The reason why we say this is
> that it is not possible to guarentee pathogen distruction relying on
> the biological heat of metabolism of the aerobic composting microbs, or
> retention time alone. We advocate solar heat pasteurization as a much
> more reliable method of pasteurization in a composting toilet process.
> As researchers associated with the Appropriate Rural Technology
> Association (ARTA) we are currently involved in a few new designs of
> solar composting toilets. Our goal is to guarentee end product
> pasteurization. From there we can more forcefully impress composting
> toilets on the permitting/regulatory agencies.

Gee, we built a Clivus Minimus, developed at Brace Research Institute
(McGill University), about 15 years ago, using concrete blocks. It is
dead simple, and has worked great - about all you need to learn to
operate it is to add woodshavings to balance the nitrogen. For a 2
family household, I've removed about 15 wheelbarrows of compost over all
that time. With a small exhaust fan to carry off the moisture the system
is always at negative pressure and there is no odor at all, unlike many
of my rural neighbours with septic systems who seem to have to be
careful about how often they flush.

Did I miss something? Needless to say, we had no building codes to
contend with, and we built some others that weren't successful (kids
leaving the seat up, throwing blankets down them, white porcelain bowl
envy, etc.). Often the problem with inherently simple things like this
appears to revolve around having to foolproof them, and not with any
innate difficulty in the biological processes.

Best......Norbert Senf
Norbert Senf email:
Masonry Stove Builders
RR 5, Shawville website:
Quebec J0X 2Y0 fax: 819.647.6082
voice: 819.647.5092
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