1088 SMALL FLOW WASTEWATER TREATMENT TECHNOLOGY FOR DOMESTIC AND SPECIAL APPLICATIONS
In recent years natural systems are also used for waste-
water treatment from small establishments and sub-divisions.
Among these are land treatment, and natural and constructed
wetland. Information on natural system may be found in
Refs. 1, 4, 15–17, 23 and 24.POLAR REGIONSWaste handling in polar regions is a complex problem.
Conventional wastewater collection and treatment systems
have severe limitations due to cold weather. Sewers con-
structed through snow, ice or permafrost^2 must be insulated
to transport the wastes without freezing. Waste treatment by
chemical or biological methods may not be possible due to
retarded reaction rates.
The predominant sanitary facility used in small Alaskan
villages is manual collection of human fecal waste and their
disposal to ground, snow or ice. In many cases, pit priv-
ies, vaults, bored holes, straddle trenches, box and can, and
crude chemical toilets are also used. Problems with these
systems are: inconvenient to use especially in cold climates,
unaesthetic features such as odor and unsightly conditions,
and health hazards. 25,26
Perhaps the most comprehensive analysis of waste prob-
lems in arctic areas was conducted by the Federal Housing
Administration about 50 years ago. 27,28 Subsequently, a
number of research programs were conducted by the US
Public Health Service, National Research Council, US Navy,
US Air Force, and US Army in developing suitable systems for
use in Greenland, Alaska and most recently in the Antarctic.^29
Prime requirements for a system suitable for installation in
these areas were: (1) minimum water use as year-round water
supply in these areas may be lacking, (2) non-electric opera-
tion, (3) freeze-free, (4) minimum final disposal problems,
(5) odor-free, and (6) minimum of maintenance. Systems
investigated in these research programs included: (1) incin-
erating toilets, (2) chemical toilets, and (3) chemical and bio-
logical toilets with recirculation.Incinerating ToiletsIncinerating toilets have been designed to destroy human
body wastes. The thermal energy required may be obtained
from electricity, fuel, oil, or liquified petroleum gas (LPG).
Several designs of incinerating toilets are now commer-
cially available. Although these toilets provide complete
prevention of pollution from human wastes, they are rela-
tively inefficient in terms of fuel consumption and often
fail to provide complete burning which may result in a nox-
ious odors or excessive smoke.^28 Two incinerating toilets
Incinolet and Stornburn are manufactured for application
in Alaska.^26Chemical and Composting ToiletsChemical toilets require addition of chemicals into the waste
storage tank. These chemicals liquify the fecal wastes, producebactericidal effect and suppress fecal odors. Most commonly
used chemicals are: (1) halogens and their compounds, (2)
coal-tar distillate (phenols and cresols), (3) heavy metals
and their salts (zinc, copper and silver salts), (4) quaternary
ammonium compounds, and (5) alkaline substances such as
sodium and potassium hydroxide and lime. Various chemi-
cals are sold in the market under different trade names.
One mechanical-flush chemical toilet was developed by
Naval Engineering Laboratory, Port Huneme, California (US
Patent No. 3,460,165) for use at remote Antarctic stations.
This toilet was extensively tested by the military personnel
and found satisfactory for polar applications.
A variety of composting toilets are on the market for
application in cold region. These toilets use no water, and
eventually produce compost that can be used on home
garden. Three composting toilets named in the literature are
AlasCan, the Phoenix, and the Sun-Mar. 26,29,30Chemical and Biological Toilets with RecirculationA special application of waste treatment unit for polar use
is a unit where treated effluent could be recirculated as a
flush fluid. Such concepts with both chemical and biologi-
cal treatment systems were investigated. Walters developed
a recirculating chlorinator toilet which used standard toilet
fittings.^31 The heavily chlorinated effluent from the storage
tank was reused for flushing the toilet bowl. The system
was tested in Alaskan single homes and results were found
esthetically acceptable.
Another study evaluated three extended aeration plants
in which the effluent was recirculated for toilet flushing.^32
The findings of this investigation showed that the flushing
fluid turned brown during the first week and remained that
color for the entire test period of several months. However,
no odors were detected.
Both the chemical and biological treatment system with
effluent recirculation have great promise in developing toilets
for use in polar regions. These toilets have unique features
such as: no water requirement, non-electrical (with hand
pump), non-freezing, no odor, conventional toilet design,
and a minimum of maintenance.
A number of innovative wastewater collection, treat-
ment, reuse and disposal system have also been applied
for community and individual home applications in polar
region. Among these are pressurized and vacuum collection
systems, low flush, ultra-low flush, micro-flush toilets, and
mineral oil flush systems. 26,33 – 38WATERCRAFTUse of the waterways for pleasure boating has increased
enormously in this country. Because of a substantial increase
in the number of recreational vessels, the public has become
aware of the potential seriousness of the waterborne pollu-
tion resulting from this source. Many recreational watercraft
and commercial and government vessels discharge wastes
into the water.^34 Recreational watercraft are highly mobile,C019_002_r03.indd 1088C019_002_r03.indd 1088 11/18/2005 11:06:46 AM11/18/2005 11:06:46 AM