General
Links and References |
Wikipedia
informative entry on urine diversion.
Sustainable
Sanitation and Water Management
(SuSanA) gives good explanation
and has very comprehensive list of
references, including materials used to
advocate switching from water-born
sewage systems.
EcoSan/SuSanA Dry Toilet construction
of all parts of unit, detailed
plans, containers, traps, use.
Note:
There are multiple ways to find the
very helpful SuSanA/EcoSan publications
(they have altered their name over the
years); can also use this link.
General technology review with
detailed references.
Del Porto, D. and C. Steinfeld (2000).
Composting Toilet System Book.
Concord, MA: Center for Ecological
Pollution Prevention (CEPP).
Some good explanations
and graphics (partly taken from
Del Porto & Steinfeld.
Overview of composting toilets:
projects at Michigan
Tech Dept of Civil and Environmental
Engineering.
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Projects
Reported |
Technology
Review of Urine-diverting dry
toilets (UDDTs): Overview of design,
operation, management and costs.
GRUPO DE TECNOLOGÍA ALTERNATIVA S.C.
Central/North-American dry toilet projects
and research. Research
results.
The Mexican Center
for Innovation in Alternative
Technology has a dry toilet
project.
UDDT projects
in Eastern Europe, includes refs
to additional studies by WECF.
EcoSan
Club Austria description of
projects in East Africa.
EcoSanRes
(Swedish partner of SuSanSa),
several projects, forums.
Excellent photos and step-by-step
descriptions for a double-vault project
in Bulgaria [in Russian and
Bulgarian].
Global
Dry Toilet Association of
Finland; alternate site.
Case studies from U.S. Appellation
Trail sites, some UD, moldering,
composting.
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Agricultural
Uses: |
Europe's
sanitation problems, UDDTs, use
of excreta in agriculture [brief WECF
paper].
Description of WECF use
of urine.
Before flush toilets, human waste was valuable
and widely used in agriculture.
See http://www.treehugger.com/bathroom-design/crapping-bill-gates-reinvent-toilet-winner.html
and also commentary on Gates Foundation
toilet project.
Story
of a failed project in China.
Successful
urban project in China using
excreta collected from UDDTs in urban
dwellings.
Productive reuse of wastes &
wastewater, solid and liquid urban
waste products safely and economically
used in agriculture: RAUF
Foundation.
An excellent resource: Humanure
Handbook, is mostly about
composting, but also includes some
toilet tips.
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Composting:
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Aerobic and anaerobic decomposition explained;
research
here on mesophilic and thermophilic
composting, including microorganism
counts.
Pathogen destruction in composting
toilets: Explained;
researched.
Also see Agricultural
Uses.
The composting chapter from Humanure
handbook; toilet tips, too.
“One may
also "precharge" the toilet with a
"biological sponge," a thick layer of
absorbent cellulose material filling
the bottom of the compost chamber…”
(Retrieved from Humanure
Handbook.) “Priming” the
chamber with material from the previous
chamber material or a commercially
available compost starter may also
improve composting activity if the
temperature is sufficient.
WECF
document on composting.
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Sanitation
Notes:
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Note:
“When planning systems, pathogens and
vectors need to be considered. This is
particularly a concern in areas with
endemic diseases, such as warm regions,
where pathogens flourish."
World Health Organization guidelines
for safe
use of human excreta (Guidelines
for the Safe Use of Wastewater,
Excreta and Greywater. Volume IV –
Ecxreta and Greywater Use in
Agriculture).
National Water Center discussion
of dry toilets vs. water-born
systems. (More
here.)
Diseases
possible from failure to isolate
human excrement.
Bacteria can be tested how? [Search
the web for water testing methods.]
Note:
Parasites are often mentioned as a
significant risk where human feces are
not treated. Specifically what
parasites should we make sure to
eliminate? Not an easy question to
answer. cite a very large number of
parasites that can cause harm in humans
(e.g., Health
care sources offer extensive
explanations). Testing of stool for
parasites may offer ideas for testing
to determine safety of desiccated feces
from dry toilets (general
explanation of tests ; most
websites describe how stool is
collected but don’t describe how the
laboratory tests themselves are done;
use of slides, dying, centrifuge,
microscopic inspection).
The most common
intestinal parasites in North
America that cause infections are:
- roundworms: Ascaris
lumbricoides
- hookworms: Necator americanus
- pinworms: Enterobius
follicularis
- tapeworms: Diphyllobothrium
latum, Taenia saginata,
and Taenia solium
- protozoa: Entamoeba
histolytica (an amoeba), and Giardia
lamblia (a flagellate)
Full listing of pathogens in EcoSan
report, page 27.
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Base and
Structure: |
National Water Center plans for 55-gal
drum UDDT stand-alone
unit.
UDDTs in cold
climates.
Omick composting
toilets with photos.
State-approved composting toilet in MA
farm
house.
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UDDT
Toilet Seats:
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UD toilet unit and accessories: Berger
Biotechnik; UD
insert/seat.
List
of sit-down UDDTs. However many on
this site are available only in China,
India, Africa.
Separett
toilet seats and associated UDDT
fittings; UDDT toilets and seat inserts
are also available from Ecovita,
978-318-7033.
Unit where one pumps
on a pedal to activate a
conveyor belt. [photos repository];
an application
of this pedal-activated unit in
Canada.
Other models available from U.K.: Freerange
Designs, Dunster
House.
Urine-diverting dry toilet (UDDT)
Technology review: overview of
design, management, maintenance and
costs.
"UD flush toilets" use small amounts
of flush water and are described in Urine
Diversion Components.
Discussion of alternatives to urine
diversion in Humanure
book.
An example of non-urine diversion
"dry" toilet appears to be the Crapper
(see the Buying
Commercial Units page); email
from principal says: “Regarding the pee
question: For urine, we have a separate
unisex urinal. The urinal is for
whenever the user just has to pee. The
CRAPPER is designed for pooping (and
peeing when you're pooping). If there
is some liquid that passes through the
drum (called leachate [any solution
resulting from leaching, often
contaminated]) it will drain out the
back through drainage holes and a
funnel system into the ground. If there
is no ground to drain into (i.e.
communities living on water), this
leachate can be filtered with an ash
pebble mixture.”
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Plumbing
and Containers: |
Separett
toilet seats and associated UDDT
fittings.
Plastic
bins and containers; more
of same, cheaper
water-tight tote bins.
Seepage bed specifications,
p. 5.
Also see below, Volume
Calculations.
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Vent
Pipes: |
An updraft-enhancing
top can be fitted to the top of the
vent pipe; also a
smaller-sized whirlybird,
ditto,
Stand-off
bracket to secure vent pipe in
position.
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Volume
Calculations: |
By one estimate, one cubic meter will
hold the feces of a group of 7 adults
and 3 children over one year,
considering shrinkage as
dehumidification occurs; another
estimate is 0.25 cubic meter will hold
250 kg of material produced by 5 adults
in one year, or 0.5 cubic meters for 10
adults [this seems too little; the
conversion from kg to liter depends on
density so is unclear in this case].
One adult can be expected to produce
approximately 0.25 liters (250 cc) of
feces in one day (range of 0.12 – 0.4
[1 cubic meter = 1000 liters, so the
range is 0.04 - 0.15 m3/year
per person]. Note that these estimates
do not seem to account for toilet paper
or the dry material added after each
bowel movement.
Urine container alternatives and
volume calculations, see Urine
Diversion Components, see GTZ
Sustainable Sanitation EcoSan (Deutsche
Gesellschaft für Technische
Zusammenarbeit). Also includes info on
"UD flush toilets", urine pipes,
containers, etc.
Feces container volume calculations,
see GTZ/GIZ publication.
Also includes other aspects.
More
volume calculations including
reduction due to drying, composting.
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Insect
Mitigation: |
Note:
Dry toilets must be managed to assure
little or no odor and to encourage
decomposition, by taking into account
circumstances and patterns of usage,
being sure ventilation and temperature
are adequate, enough absorbent bulking
material is added, and perhaps leveling
the mound of feces so it remains
covered and odorless. The chutes or
feces holes from the toilet may require
cleaning from time to time. In the
event that insects penetrate and begin
to breed, they must be exterminated;
most common (when they occur) are small
black flies (larger than fruit flies,
smaller than house flies) - usually Ephydridae
fly larve; be sure air intakes and vent
pipes have netting; lengthen vent pipe
to increase flow, install fly traps
within vault.
Ideas for preventing insects: Del
Porto and Steinfeld, Composting
Toilet System Book, pp 59-60;
Organic insecticides such as
Rotenone/Pyrethrin concentrate might be
used if necessary.
“Diatomaceous earth consists of
fossilized remains of diatoms, a type
of hard-shelled algae. It is used as a
filtration aid, mild abrasive in
products including toothpaste,
mechanical insecticide…” Inexpensive,
safe, etc. quoted from here;
available here.
Zeolite diatomic earth is said to be a
positive amendment to compost.
Omick Insect
trap with photos; includes info
on non-UD versions, legal issues,
aesthetics, secondary processing,
agriculture.
Fly
traps available.
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Miscellaneous
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Proceeds of dry
toilet conference in Finland.
Legal issues discussed in Omick;
projects to explore legal
composing toilets.
A somewhat skeptical
appraisal of composting toilets
in the popular press, (although not
speaking of UDDTs in particular).
Colorful posters and explanatory
material, were once available from
George Anna Clark, Espacia de Salud,
A.C., A.P. 1-1576, Cuernavaca, Morelos,
62001 Mexico, or esac@laneta.apc.org
. Search for César Añorve for another
source.
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Photo and Image Credits
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CIAT
Center for Innovation in
Alternative Technology
DTS
Dry Toilet Savvy
ESR
(EcoSanRes, Stockholm Environment
Institute)
GIZ Deutsche
Gesellschaft für Internationale
Zusammenarbeit GmbH; archives
listed.
GTA
GRUPO DE TECNOLOGÍA ALTERNATIVA S.C.
GWA
Grey Water Action
MTU
Michigan Tech Dept of Civil and
Environmental Engineering
OMK
Omick: Living Outside the Box - A
Few Simple Technologies for Daily
Living
RVS
Riversong HouseWright
SSWM
Sustainable Sanitation and Water
Management
SSA
SuSanA Secretariat - Sustainable
Sanitation
WECF
Women in Europe for a Common Future
Creative
Commons license (used by GWA,
SSA, and others)
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Research
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GRUPO DE TECNOLOGÍA ALTERNATIVA - Research
results.
Microbial
Exposure and Health Assessments in
Sanitation Technologies and Systems.
Results of Stockholm Environmental
Institute project to produce
organic fertilizer from UDDTs in
China.
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[yet to be categorized:]
Biorealis
Systems, Inc Low Cost Site-Built
Composting Toilet System, partially discussed;
plans for sale.
University of Colorado hi
tech toilet funded by Gates Foundation.
RETHINKING
SUSTAINABLE SANITATION FOR THE URBAN
ENVIRONMENT, history
of sanitation over last 150 years, discussion
of sustainable approaches by region of the
world.
Sustainable Sanitation Alliance (SuSanSa)
list of publications, includes sanitation
as a business, role of different players in
sustainable sanitation, capacity development,
case studies, etc.
Urine Diverting Toilets in Climates with Cold
wide temperature variations; includes
general discussion and case descriptions.
Discussion of post-processing
and vermicomposting.
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