1. Amended Soil Filter is a sand filter that filters out solids
and provides a medium for bacteria to break down organic material
in the greywater.
2. Sand Filtration uses three tanks for (1) settling suspended
solids, (2) overflow which diverts excess into a deep bed sand filter
for filtration, and (3) containment of the filtered water before pumping
into an irrigation field.
3. Aerobic Microbial Respiration and Evapo-transpiration filters
all greywater through growing plants. This is achieved by:-
a. Filtering the greywater at the source i.e. grease/oil interceptors
for the kitchen sink and a fabric particle filter on the washing
machine.
b. Directly irrigating thirsty plants (phreatophytes) in an aerobic
evapo-transporation bed lined with an impervious membrane.
c. Mineralisation by microbes in the planting medium removes the
carbon content, and the balance of the water is evaporated or transpired
via the plants. (These plants used are hardy, rapid growing and
have high water requirements). And
d. Greywater is be cleaned by passing it through filters, and root
systems of certain plants.
4. Wet Composting Vermicomposting toilet can be modified to
receive black and greywater. Blackwater is combined with greywater
in a second tank where aeration occurs around submerged volcanic rock
media to achieve secondary standard treatment. The effluent then goes
to an irrigation tank in which chlorination occurs before being utilized.
5. Constructed Wetlands utilise aerated tanks to remove nitrogen
and phosphates, with subsequent sterilisation of pathogens by ultraviolet
sterilization. A wetland is constructed wholly within the site specifications,
using local plants with proven performance in wastewater wetlands.
Biodiversity of plants will foster aeration and optimal nutrient uptake
across all seasons and effluent from the wetland can eventually be
used in gardens.
6. Aerobic Treatment Units These may have 5 chambers:-
a. primary sedimentation and aerobic digestion, which can be removed
if only greywater is used,
b. anoxic chamber for phosphorus removal,
c. aerobic biological oxidation, including nitrification and denitrification,
d. secondary clarifier and sludge recycling, and
e. chlorination and storage for irrigation.
Links
http://www.infobluemountains.net.au/david/green/links_water.htm
