2. Introduction :
Land areas that are wet during
part or all of the year are referred
as wetlands.
Decentralized waste water treatment
system.
Low operational cost
important role in many ecological
sanitation concepts.
These are secondary treatment.
Water reuse.
3. Classification of wet lands:
- Typically a constructed
wetland can be
classified as:
- free water
surface flow
- subsurface
flow
- horizontal
- vertical
4. Process description :
Pre treatment
material that are easily collected(tree, leaves)
Screening
pass through bar (cans ,plastic packet)
Girt removal
settlement of sand ,girt, stones.
Primary treatment
to settle sludge and to remove oil and grease
Bio filtration
periphyton(group of micro organism that
break down organic material)
5. Horizontal flow beds(HFB)
common type of subsurface flow constructed wetland
low maintenance requirements.
interesting option especially in locations
without energy supply and low hydraulic gradient.
the wastewater flows slowly through the porous medium
under the surface of the bed in a horizontal path until it
reaches the outlet zone.
At the outlet the water level in the HFB is controlled
with an adjustable standpipe.
For continuous operation the submerged height of the bed
should be less than one third of the total height of the filter
bed to avoid anaerobic conditions in the bed.
7. Vertical flow bed(VFB)
higher treatment efficiency
Safer and more effective at removing the more directly
harmful toxic trace metals
Expensive Compared to Surface Flow
In VFBs wastewater is intermittently pumped onto the
surface and then
drains vertically down through the filter layer towards
a drainage system at the bottom.
The intermittent batch loading enhances the oxygen
transfer and leads to high aerobic degradation
activities.
9. Chemical process
general contamination removal
physical
chemical and biological process
specific contaminant removal
nitrogen( ammonia )
Phosphorus
biochemical oxygen demand removal and
chemical oxygen demand
total suspended solids
fish and bacteria
10. Nitrogen (ammonia) Removal :
It form by mineralization or ammonifiacation of
organic matter
Primary source for most flooded wetland soil
Ammonifiacation:
NH3 + H2O (NH4+) + OH −⇌
Absorbed by plant or by electro statically on negatively
charged surface(anaerobic condition)
Nitrification
Bacteria responsible (nitrosomonas and nitrobacter)
11. Phosphorus removal
Occur naturally both in organic and in organic form
Soluble reactive phosphate
Dissolved organic and inorganic phosphorus are generally not
biologically available until transform into soluble organic form
Binding of phosphorus
Precipitation of insoluble phosphorus with ferric iron calcium
and aluminum
Transient nutrient storage compartment
Luxury uptake of nutrient
Aquatic phosphorus (if harvested extend life of system)
12. Bio chemical oxygen demand
Chemical oxygen demand
Amount of oxygen consumed by micro organism during
biological reaction
Different bio activity of microbes with temperature
increase turbidity and light penetration.
Total suspended solid
13. Graph for specific contaminant removal
under hot and cold condition
nitrogen phosphorus
For bod and cod
14. Various Plant Types
Water Hyacinths Eichhornia crassipes
Forage Kochia Kochia spp
Poplar Trees Populus spp
Willow Trees Salix spp
Alfalfa Medicago sativa
Cattail Typha latifolia
Coontail Ceratophyllum demersvm L
Bullrush Scirpus spp
Reed Phragmites spp.
American pondweed Potamogeton nodosus
Common Arrowhead Sagittaria latifolia
15. Application
Though built to treat wastewater, constructed
wetlands provide habitat for:
Birds
Municipal wastewater treatment
Treatment of household wastewater or grey water
Tertiary treatment of effluents from conventional
wastewater treatment plants
Sludge dewatering and mineralization of fecal sludge
or sludge from settling tanks.
Storm water treatment and temporary storage
Treatment of water from swimming pools without
chlorine.
16. Conclusion :
Increase water quality
stop pollution
think for a solution
Bring out a revolution
constructed wetlands are referred as kidneys
of mother land.
Editor's Notes
Reclamation of Wastewater global trend as a way to increase water supplies. Natural method for WW treatment Low Cost No additives Water scarcity is the major issue in all parts of world. Wastewater reuse is one alternative. SAT proves to efficient, economical and feasible method for wastewater treatment. SAT system achieves an excellent reduction of biochemical oxygen demand, suspended solids, and fecal coliform. About 90% of water applied to SAT site is returned to watershed.
Nitrogen pre-treatment is capable of efficiently removing nitrogen prior to SAT and has a major effect on the total oxygen demand. Nitrogen Removal - concern when secondary effluents are applied with total nitrogen concentrations greater than 10 mg-N/L . Sufficient oxygen demand to create anoxic conditions was necessary to promote nitrogen removal during SAT nitrogen removal was observed at efficiencies of 50% or greater at sites where anoxic or anaerobic conditions developed. Nitrate - primary form of nitrogen in applied effluents, concentrations ranged from 2-8 mg N/L mass of nitrate removed limited by the amount of available biodegradable carbon exception - wetland system plants provided an abundant source of carbon to efficiently remove nitrate during infiltration. Ammonia - primary form of nitrogen applied at concentrations greater than 10 mg-N/L, the high nitrogen removal efficiencies could not be explained by heterotrophic denitrification since insufficient carbon was present. Therefore, the mechanism of anaerobic ammonia oxidation (ANAMMOX) sustainable mechanism for nitrogen removal During SAT - possible for adsorbed ammonia to serve as an electron donor to convert nitrate to nitrogen gas . Since adsorbed ammonia is available for nitrification when oxygen reaches soils containing adsorbed ammonia, ANAMMOX activity could occur as nitrate percolates through soils containing adsorbed ammonia under anoxic conditions. This implies that there is a sustainable mechanism for nitrogen removal during SAT when effluent pre-treatment does not include nitrogen removal and the majority of applied nitrogen is ammonia. Appropriate wetting/drying cycles are necessary to promote nitrification in the upper vadose zone during drying cycles.
Nitrogen pre-treatment is capable of efficiently removing nitrogen prior to SAT and has a major effect on the total oxygen demand. Nitrogen Removal - concern when secondary effluents are applied with total nitrogen concentrations greater than 10 mg-N/L . Sufficient oxygen demand to create anoxic conditions was necessary to promote nitrogen removal during SAT nitrogen removal was observed at efficiencies of 50% or greater at sites where anoxic or anaerobic conditions developed. Nitrate - primary form of nitrogen in applied effluents, concentrations ranged from 2-8 mg N/L mass of nitrate removed limited by the amount of available biodegradable carbon exception - wetland system plants provided an abundant source of carbon to efficiently remove nitrate during infiltration. Ammonia - primary form of nitrogen applied at concentrations greater than 10 mg-N/L, the high nitrogen removal efficiencies could not be explained by heterotrophic denitrification since insufficient carbon was present. Therefore, the mechanism of anaerobic ammonia oxidation (ANAMMOX) sustainable mechanism for nitrogen removal During SAT - possible for adsorbed ammonia to serve as an electron donor to convert nitrate to nitrogen gas . Since adsorbed ammonia is available for nitrification when oxygen reaches soils containing adsorbed ammonia, ANAMMOX activity could occur as nitrate percolates through soils containing adsorbed ammonia under anoxic conditions. This implies that there is a sustainable mechanism for nitrogen removal during SAT when effluent pre-treatment does not include nitrogen removal and the majority of applied nitrogen is ammonia. Appropriate wetting/drying cycles are necessary to promote nitrification in the upper vadose zone during drying cycles.
Nitrogen pre-treatment is capable of efficiently removing nitrogen prior to SAT and has a major effect on the total oxygen demand. Nitrogen Removal - concern when secondary effluents are applied with total nitrogen concentrations greater than 10 mg-N/L . Sufficient oxygen demand to create anoxic conditions was necessary to promote nitrogen removal during SAT nitrogen removal was observed at efficiencies of 50% or greater at sites where anoxic or anaerobic conditions developed. Nitrate - primary form of nitrogen in applied effluents, concentrations ranged from 2-8 mg N/L mass of nitrate removed limited by the amount of available biodegradable carbon exception - wetland system plants provided an abundant source of carbon to efficiently remove nitrate during infiltration. Ammonia - primary form of nitrogen applied at concentrations greater than 10 mg-N/L, the high nitrogen removal efficiencies could not be explained by heterotrophic denitrification since insufficient carbon was present. Therefore, the mechanism of anaerobic ammonia oxidation (ANAMMOX) sustainable mechanism for nitrogen removal During SAT - possible for adsorbed ammonia to serve as an electron donor to convert nitrate to nitrogen gas . Since adsorbed ammonia is available for nitrification when oxygen reaches soils containing adsorbed ammonia, ANAMMOX activity could occur as nitrate percolates through soils containing adsorbed ammonia under anoxic conditions. This implies that there is a sustainable mechanism for nitrogen removal during SAT when effluent pre-treatment does not include nitrogen removal and the majority of applied nitrogen is ammonia. Appropriate wetting/drying cycles are necessary to promote nitrification in the upper vadose zone during drying cycles.
Nitrogen pre-treatment is capable of efficiently removing nitrogen prior to SAT and has a major effect on the total oxygen demand. Nitrogen Removal - concern when secondary effluents are applied with total nitrogen concentrations greater than 10 mg-N/L . Sufficient oxygen demand to create anoxic conditions was necessary to promote nitrogen removal during SAT nitrogen removal was observed at efficiencies of 50% or greater at sites where anoxic or anaerobic conditions developed. Nitrate - primary form of nitrogen in applied effluents, concentrations ranged from 2-8 mg N/L mass of nitrate removed limited by the amount of available biodegradable carbon exception - wetland system plants provided an abundant source of carbon to efficiently remove nitrate during infiltration. Ammonia - primary form of nitrogen applied at concentrations greater than 10 mg-N/L, the high nitrogen removal efficiencies could not be explained by heterotrophic denitrification since insufficient carbon was present. Therefore, the mechanism of anaerobic ammonia oxidation (ANAMMOX) sustainable mechanism for nitrogen removal During SAT - possible for adsorbed ammonia to serve as an electron donor to convert nitrate to nitrogen gas . Since adsorbed ammonia is available for nitrification when oxygen reaches soils containing adsorbed ammonia, ANAMMOX activity could occur as nitrate percolates through soils containing adsorbed ammonia under anoxic conditions. This implies that there is a sustainable mechanism for nitrogen removal during SAT when effluent pre-treatment does not include nitrogen removal and the majority of applied nitrogen is ammonia. Appropriate wetting/drying cycles are necessary to promote nitrification in the upper vadose zone during drying cycles.
Many plants have been used in Phytoremediation. List above represents some of the variety used. In this presentation, I will be discussing the phytoremediation capabilities of some of these. A major effect of waste water treatment with plants was the elimination of the disturbing smell. Water Environment Research, May-June 2004 issue – exp. Used naturally growing plants along the Kishon River for wastewater purification. Plants consume part of the pollutants and
