WASTE
WATER
TREATMENT




HOW WATER IS CLEANED

WASTE WATER TREATMENT TECHNOLOGY

AEROBI TREATMENT SYSTEM

ANAEROBIC TREATMENT SYSTEM

DUAL DIGESTION

SEPTIC DRAIN FIELDS

SEPTIC TANT

FRENCH DRAIN SYSTEM

CESSPIT/CESSPOOL

REEDBED

CONSTRUCTED WETLANDS

SLOW SAND FILTERS

SLOW SAND FILTERS FEATURES

SLOW SAND FILTERS ADVANTAGES

ACTIVATED CARBON FILTERS AC

ULTRAVIOLET FILTERS UV

WATER DISTILLATION

REVERSE OSMOSIS

LIVING MACHINES ECO-CITIES

LEACH FIELD

WASTE WATER TREATMENT LINKS



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SECTION 1



HOW
WATER
IS
CLEANED




Several factors determine the best
approach to water purification in
rural communities in countries as
label third world.


Most significant
among these are:


Cost:
Villagers in rural third world
countries cannot afford expensive
techniques.


Reliability:
The purification system must
operate for years with
essentially no maintenance.


Power:
The ideal system will not be
dependent on external power
or sunlight to function.


Location:
Extensive field experience has
determined that locating the
water purification in the home
produces the most effective
results.


Simplicity:
Education of the consumer and
follow-up monitoring by trained
personnel are essential to success.

The simpler the system,
the better the outcome.


Availability:
The equipment must be constructed
from materials readily available
in-country.




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SECTION 2



LIST
OF
WASTE
WATER
TREATMENT
TECHNOLOGY




Activated sludge

Aerobic granular reactor

Anaerobic clarigester

Anaerobic digestion

Anaerobic lagoon

Bioconversion of biomass
to mixed alcohol fuels

Cesspit

Combined sewer

Composting toilet

Constructed wetland

Expanded granular
sludge bed digestion

Floculation

Flotation process

Imhoff tank

Living machines

Reed bed

Septic tank

Sequencing batch reactor

Sewage treatment

Ultraviolet disinfection

Upflow anaerobic sludge
blanket digestion

Wet oxidation




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SECTION 3



AEROBIC
TREATMENT
SYSTEM
ATS




An aerobic treatment system or ATS,
often called (incorrectly) an aerobic
septic system is a small scale sewage
treatment system similar to a septic
tank system, but which uses an aerobic
process for digestion rather than the
anaerobic process used in the septic
systems.

These systems are commonly found in
rural areas where public sewers are
not available, and may be used for a
single residence or for a small group
of homes.


Process:

The ATS process generally
consists of the following
phases:


Pre-treatment stage,
to remove large solids
and other undesireable
substances from the
wastewater.


Aeration stage,
where the aerobic
bacteria digest
the biological
wastes in the
wastewater.


Settling stage,
to allow any
undigested solids
to settle.
This forms a sludge
which must be
periocally removed
from the system.


Disinfecting stage,
where chlorine or
similar disinfectant
is mixed with the water,
to produce an antiseptic
output.




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SECTION 4



ANAEROBIC
TREATMENT
SYSTEM




Anaerobic is a technical word
which literally means without
air (where "air" usually means
oxygen), as opposed to aerobic.

In wastewater treatment the
absence of oxygen is indicated
as anoxic; and anaerobic is used
to indicate the absence of any
electron acceptor:


nitrate,
sulfate,
oxygen.


Anaerobic adhesive
is a bonding product that does not
cure as long as it remains exposed
to air.

Anaerobic may
refer to:


Anaerobic clarigester,
is a form of anaerobic
digester.


Anaerobic contact
process,

is a type of anaerobic
digester.


Anaerobic digestion,
(AD)

is the harnessed and
contained, naturally
occurring process of
anaerobic decomposition.


Anaerobic filter.

Anaerobic glycolysis,
the conversion from
sugar to alcohol
using yeast.

Fermentation
(biochemistry)


Anaerobic lagoon,
used to dispose of
animal waste,
particularly that
of cows and pigs.


Anaerobic organism,
any organism that does
not require oxygen for
growth.


Anaerobic respiration,
oxidation of molecules
in the absence of oxygen
monoxide.


Anaerobic ammonium
oxidation, anammox,

the microbial process
combining ammonium and
nitrite.




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SECTION 5



DUAL
DIGESTION
SYSTEM




Dual Digestion is a proven,
two step sludge digestion
process that combines the
best features of both
aerobic and anaerobic sludge
digestion.


Dual Digestion combines a short retention
time aerobic digestion step followed in
series by a high rate anaerobic digestion
step.


The Dual Digestion
system features:


An autothermal: with no
external heat source,
one to two day retention
time aerobic digestion
step capable of operating
either thermophilically
or mesophilically.

A high rate, eight to ten
day retention time anaerobic
digestion step that completes
the sludge digestion process,
producing usable digester gas
containing 60%-65% methane as
a byproduct.

Significantly improved process
stability compared to the
conventional anaerobic digestion.

Continuous flow operation.

Simple process control, which
minimizes operating manpower
requirements.

Very low total mechanical
energy requirements.

Significantly greater usable
digester gas than from the
conventional anaerobic digestion
because the process requires no
gas for digester heating purposes.

When operated thermophilically,
the process produces a digested
sludge product meeting the 503
“Class A” biosolids requirements.

Offers a cost effective sludge
digestion solution for either
new plants or old plants with
anaerobic digesters that are
undersized.

Dual Digestion is intended for
use at facilities that currently
have the overloaded anaerobic the
digesters and/or a need to upgrade
to the technology that produces a
Class A biosolids product.




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SECTION 6



SEPTIC
DRAIN
FIELDS




Septic drain fields are used
to remove contaminants and
impurities from the liquid
that emerges from the septic
tank.

This is typically done by burying
perforated pipes in trenches and
allowing the liquid to leach out
and the surrounding soil absorbs
the unwanted waste. Another term
for this is a:


leach field,
or french drain.


The design of the septic drain field
is determined by the size of the
dwelling that it serves and the soil
conditions.

The soil conditions would be tested
by a method called a perc test. An
engineer or licensed designer may be
required to work with the local
governing agency to design a system
that conforms to these criteria.




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SECTION 6A



A
SEPTIC
TANT




A septic tank,
the septic drain field,
and the associated piping
comprise a complete septic
system.


These systems are commonly found in
rural areas where public sewers are
not available, and may be used for a
single residence or for a small group
of homes.




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SECTION 7



FRENCH
DRAIN
SYSTEM




French drain refers to a ditch
filled with gravel, rock that
redirects surface and ground
water away from an area.

They are commonly used to
prevent ground and surface
water from penetrating or
damaging building foundations.

French drains are also used to
accommodate water that flows
from the outlet of a typical
septic tank sewage treatment
system.


In addition to this;
French drains are
used behind the
retaining walls
to relieve pressure
from ground water.


Some variations:

filter drain,
is to drain groundwater.

collector drain,
(or inteceptor drain)
combines groundwater
drainage with the
interception of surface
water or run-off.


dispersal drain,
distributes the waste
water from a septic
tank.


fin drain,
uses a perforated
pipe with a thin
vertical section
(the fin) of
drainage composite
above.
The advantage is
that the fin drain
is narrower,
(200mm or 7 inches)
than a traditional
french drain
(450mm or 17 inches and up),
and cheaper to build.




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SECTION 8



CESSPIT
CESSPOOL




A cesspit,
cesspool,
is a pit,
conservancy tank,
or covered cistern,
which can be used
for sewage or refuse.


These systems are commonly found in
rural areas where public sewers are
not available, and may be used for a
single residence or for a small group
of homes.




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SECTION 9



REEDBEDS




In nature,
reedbeds are basically
’temporary’ habitats.


Under normal circumstances,
an unmanaged reedbed shows
a succession from young reed
colonising open water or wet
ground through a gradation of
increasingly dry ground.

As reedbeds age, they build
up considerable litter layer
which eventually rises above
ground or water level, and
ultimately provides the
opportunities for scrub or
woodland invasion.


Naturally developing
reedbeds are found in:
floodplains,
waterlogged depressions,
and estuaries.

Constructed wetlands,
are artificial reedbeds,
sometimes called
"reed fields",
which are increasingly being
adopted for the efficient
small-scale sewage treatment
systems: water trickling
through the reed bed is
rapidly cleaned up by the
extensive root system and
its associated microorganisms
utilising the sewage for growth
nutrients, giving an extremely
clean effluent.




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SECTION 10



CONSTRUCTED
WETLAND
MARSH
SWAMP




CONSTRUCTED
WETLAND


A constructed wetland is an
artificial marsh or swamp,
created for anthropogenic
discharge such as wastewater,
stormwater runoff or sewage
treatment, and as habitat for
wildlife, or for land
reclamation after mining or
other disturbance.


Natural wetlands act as biofilters,
removing sediments and pollutants
such as heavy metals from the water,
and constructed wetlands can be
designed to emulate these features.

Vegetation in a wetland provides a
substrate (roots, stems, and leaves)
upon which microorganisms that break
down organic materials can grow.


Constructed wetlands
are of two basic types:
subsurface-flow,
surface-flow wetlands.

Subsurface-flow wetlands
can be further classified
as:
horizontal flow,
vertical flow,
constructed wetlands.


Subsurface-flow
wetlands move:


effluent agricultural
or mining runoff,

tannery or meat
processing wastes,

wastewater from sewage
or storm drains,

other water to be
cleansed through
a gravel or sand
medium on which
plants are rooted;



surface-flow
wetlands move:


effluent above the
soil in a planted
marsh or swamp,

and thus can be supported
by a wider variety of soil
types including bay mud and
other silty clays.




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SECTION 11



SLOW
SAND
FILTERS




slow sand
filter;

design;

operation and
maintenance;

microbiological
contaminants;

small systems;

pretreatment;


slow sand filters,
slow sand,
iron filters,
low tech,
non chemical,
water privatization,
roughing filters,
organic farming.


Slow sand filters are used in water
purification for treating raw water
to produce a potable product.

They are typically 1 to 2 metres deep,
can be rectangular or cylindrical in
cross section and are used primarily
to treat surface water.




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SECTION 11A



SLOW
SAND
FILTER
FEATURES




Slow sand filters have
a number of unique
qualities:

Unlike other filtration
methods, slow sand filters
use biological processes to
clean the water, and are
nonpressurized systems.

Slow sand filters do not
require chemicals or
electricity to operate.


Cleaning is traditionally by
use of a mechanical scraper,
which is usually driven into
the filter bed once it has
been dried out.

However, some slow sand filter
operators use a method called
"wet harrowing", where the sand
is scraped while still under
water, and the water used for
cleaning is drained to waste.


For municipal systems there
usually is a certain degree
of redundancy, it is desirable
for the maximum required
through put of water to be
achievable with one or more
beds out of service.


Slow sand filters require
relatively low turbidity
levels to operate efficiently.

In summer conditions and in
conditions when the raw water
is turbid, blinding of the
filters occurs more quickly
and the pre-treatment is
recommended.


Unlike other water filtration
technologies that produce water
on demand, slow sand filters
produce water at a slow, the
constant flow rate and are
usually used in conjunction
with a storage tank for peak
usage.

This slow rate is necessary
for healthy development of
the biological processes in
the filter.


While many municipal water
treatment works will have
12 or more beds in use at
any one time, smaller
communities or households
may only have one or two
filter beds.


In the base of each bed is
a series of herringbone
drains that are covered with
a layer of pebbles which in
turn is covered with coarse
gravel.

Further layers of sand are
placed on top followed by a
thick layer of fine sand.

The whole depth of filter
material may be more than
1 metre in depth, the
majority of which will be
fine sand material.

On top of the sand bed sits
a supernatant layer of raw,
unfiltered water.




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SECTION 11B



SLOW
SAND
FILTER
ADVANTAGES




As they require
little or no
mechanical power,
chemicals or
replaceable parts,
and they require
minimal operator training
and only periodic maintenance,
they are often an appropriate
technology for poor and
isolated areas.

"Under suitable circumstances,
slow sand filtration may be
not only the cheapest and the
simplest but also the most
efficient method of water
treatment.

Most units require a constant
flow of water to work correctly,
and so wouldn't be suitable for
well water treatment.




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SLOW
SAND
FILTER
LINKS




Biosandfilter.org
http://www.biosandfilter.org/

Blackburn and Associates
http://www.slowsandfilter.com/

Manz Water Info
http://www.manzwaterinfo.ca/

Oasis Design
http://www.oasisdesign.net/



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SECTION 12



ACTIVATED
CARBON
(AC)
WATER
FILTERS




Activated Carbon Filtration
is an established technology
that works through absorption
of the problematic compounds,
primarily to remove taste and
odour but systems will also
remove some harmful contaminents.

AC is a highly porous material
with a very large surface area.
Chemical pollutants are attracted
to and held by the AC's surface.

These water filters are best suited
for the removal of organic compounds.




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SECTION 13



ULTRAVIOLET
(UV)
WATER
FILTERS




UV Filters are able to
kill the majority of
bacteria and viruses
in the water which
passes through them.

However, they won't
remove some chemical
pollutants from the
water.

Also you should note
that the treatment is
ineffective outside of
the treatment area, so
water should be used
immediately after it
is treated.




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SECTION 14



WATER
DISTILLATION
WATER
DISTILLERS




Water Distillation involves
heating the water to boiling
point and condensing the
steam.

Pollutants with a boiling boint
near that of water are hard to
remove, but generally the
distilled water is of a very
high quality.

The major drawback to this
method is that it requires a
large amount of energy.
Some people will also complain
that the distilled water tastes
flat.

This is due to less dissolved
oxygen.




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SECTION 15



REVERSE
OSMOSIS




In water filter terms,
reverse osmosis
hyper-filtration:
is the process of filtering
water under pressure through
a semi-permeable membrane,
allowing water to pass through
but rejecting other particles
such as:
bacteria,
toxins,
salts,
and anything bigger than
around 150 Daltons.




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SECTION 16



ECO-CITIES
LIVING
MACHINES




Living machines represents a conceptual
variant on intelligent machines, and has
mostly been associated with water the
treatment systems that make use of the
natural bioremediation processes such as
wetlands to remove contaminants from sewage
and other waste water sources.

The earliest living machines were developed
and designed by John Todd and Nancy Jack Todd
of Ocean Arks International, beginning in the
1990s.


What is a
Living Machine?


A Living Machine is an advanced biofilter
that has been designed to treat blackwater
sewage.
What demarks the living machine is the fact
that it does the job of eliminating the human
threat to our lakes, streams and oceans, through
the purification of our raw sewage.




OCEAN ARKS INTERNATIONAL
http://www.oceanarks.org/



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ECO-CITIES
LIVING
MACHINES
LINKS:




In Context
http://www.context.org/

EnviroEducation
http://www.EnviroEducation.com

THE GREEN CENTER
http://www.fuzzylu.com/greencenter/index.htm

Living Designs Group
http://www.livingdesignsgroup.com/

NEW ALCHEMY
http://www.fuzzylu.com/greencenter/list.htm

Rainwater Harvesting Guide
http://www.rain-barrel.net/

OCEAN ARKS INTERNATIONAL
http://www.oceanarks.org/

WHOLE EARTH MAGAZINE
http://www.wholeearthmag.com



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SECTION 17



LEACH
FIELDS




LEACHING
Washing out of soluble substances by
water passing down through soil.


LEACH FIELDS
A drainage area where minerals in water
are gradually dispersed in soils and are
absorbed by plants.




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LEACH
FIELDS
LINKS




ALL SEPTIC SYSTEM
INFORMATION WEBSITE

http://www.inspect-ny.com/

BIOREACTOR
http://www.bioreactor.org/

IOWA WASTE REDUCTION CENTER
http://www.iwrc.org/

THE NATURAL HOME
http://www.thenaturalhome.com/

SEPTIC-SYSTEM
http://www.septic-system.com/

TOOLBASE SERVICES
http://www.toolbase.org/

VIRINIA COOPERATIVE EXTENSION
http://www.ext.vt.edu/



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SECTION 18



WASTE
WATER
TREATMENT
LINKS




Aerated Lagoons
http://www.lagoonsonline.com/

The American Ground
Water Trust

http://www.agwt.org/

The American Water
Works Association's

http://www.awwa.org/

center for alternative technology
http://www.cat.org.uk/

Consortium of Institutes for
Decentralized Wastewater Treatment

http://www.onsiteconsortium.org/

Environmental Expert.com
http://www.environmental-expert.com/

Green Pages
http://www.eco-web.com/

Hydro Resources International
http://www.olawai.org/



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Lenntech
http://www.lenntech.com/

National Ground
Water Association

http://www.ngwa.org/

WaterAid
http://www.wateraid.org.uk/

Water Health Connection
http://www.waterhealthconnection.org/

Water Technology Online
http://www.watertechonline.com/

World Health Organization
http://www.who.int/en/

Water and Wastewater.Com
http://www.waterandwastewater.com/



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