grey water management for environment engineering.ppt

Management of house hold grey water for sustainable approch of water management

1. GREY WATER
REUSE
CREATED BY:-
PARTH. P. DESAI

2. CONTENTS
Introduction
Types of domestic waste water
What is grey water?
Grey water reuse
Reuse system of grey water
1.Grey water Diversion System
2.Grey water Treatment System
Advantages
Conclusion
References

3. INTRODUCTION
•Fresh water is an essential living resource. But
unfortunately, it is also becoming a scarce resource.
•The majority of fresh water used for indoor domestic
purposes is discharged after use as ‘wastewater’ & treated
at a conventional wastewater treatment plant.
•In seeking greater sustainability in water resources
management, wastewater is now being considered more as
a resource than as a waste—a resource for water, for plant
nutrients, and for energy.
•It can be collected, treated and re-used on-site, thereby
promoting more efficient water use & enhance economic
and environmental benefits for the community.

4. TYPES OF DOMESTIC WASTE WATER
•There are two main types of domestic wastewater:
1.Black water - wastewater from the toilet
2.Grey water - all other domestic wastewater, including
wastewater from bathrooms, kitchens and laundries.
•A typical household discharges approximately 35 litres of
black water, and 105 litres of grey water, per person per day.
•Grey water contributes about 65% of the volume of domestic
wastewater, 70% of the phosphorus, and 63% of the BOD,
while black water contributes about 35% of the volume of
wastewater, 61% of suspended solids, 82% of nitrogen and
37% of BOD. presence of pathogens in grey water is
substantially lower than in black water.

5. WHAT IS GREY WATER?
•Water generated from domestic activities like taking a
bath, washing hands, and doing laundry. Not include
waste water from toilets, urinals and kitchens.
•Black water generated from toilets, urinals and kitchens
can contain heavy loads of organic material, fats and
caustic additives.
•Due to lower microorganisms concentrations than found
in black water grey water is much safer for reuse.
Although it may contain grease, food particles, hair, and
any number of other impurities, it may still be safely
reused if the proper systems are implemented.
•These systems mostly maintain that grey water not be
stored for long periods of time, but instead readily reused.

6. REUSE OF GREY WATER
•Reusing grey water serves two purposes:
1.It reduces the amount of freshwater needed to supply a
household.
2.Reduces the amount of waste water entering sewer or
septic systems.
•It is essential for reusing grey water to separate it from
the plumbing system used for black water for ensuring
that it does not obtain higher concentrations of harmful
and disease-inducing microorganisms.
•There are two main categories of systems: the diversion
systems and the filtration and purification systems.

7. REUSE SYSTEM FOR GREY WATER
In sewered residential premises, grey water may be reused
in one of two ways:

1.Grey water Diversion System
2.Grey water Treatment System

8. GREY WATER DIVERSION SYSTEMS
•It generally divert the grey water from the laundry, bath,
shower, and sink sources to a site or sites of immediate reuse.
•It may permanent plumbing and irrigating systems that are
integrated into the established plumbing system of the
building.
•For a private home, the diversion system would, after use,
divert the grey water to the garden without purification process
because it is never stored for more than a couple of hours.
•If it were stored for more than a few hours without being
purified the bacteria would grow at high rates, causing the bad
smell and possibly be harmful to people.

9. Continue….

10. Continue….
•Grey water may contain traces of dirt, food, grease, hair,
and certain household cleaning products. It may look
“dirty,” but it is a safe and even beneficial source of
irrigation water in a yard as they are valuable fertilizer
also save water (and money on your water bill).
•If released into rivers, lakes, or estuaries, the nutrients in
grey water become pollutants,
•Reusing grey water keeps it out of the sewer or septic
system, thereby reducing the chance that it will pollute
local water bodies.

11. Grey water Purification & Filtration
Systems
•The treatment systems involve the removal of bacteria and
organic particles through filters and disinfection technologies.
•Cycle: sources to a purification treatment, then ultimately a
grey water service tank. From the service tank, it is
redistributed to various uses throughout household.
•After undergoing the purification process, the grey water is
potable or nearly potable.
•The purification treatments are often broken down into many
stages and levels like pre-treatment (screening) then a
distillation process (though it is rather intense and not
necessary). Sand bed filters are often used to remove the
smaller particles from the grey water.

12. Continue….
•The grey water then enters a type of biofiltration include soil box
planters, living green walls, green roofs, & reed beds for the
further removal of particles within the water.
•The roots of the plants further purify the grey water by absorbing
the nutrients in the water.
•For incredibly high quality grey water, many filtration systems
include a UV disinfection stage.
•After treatment it is either stored in a holding tank or dispersed to
household areas for further reuse. Storage in a tank is a common
practice due to rarely use as fast as it is produced.
•The grey water is then dispersed via plumbing pipes to toilet
bowls, garden irrigation systems, or, in the case of the UV
disinfected grey water, to washing machines.

13. Grey water biofiltration

14. ADVANTAGES
•Decrease in demand for fresh water.
•Decrease in discharge of wastewater into the environment.
•Reduction in the amount of energy needed to transport water.
•Reduced amount of greenhouse gas emissions. (as a result of
the reduced amount of transportation energy needed)
•Plants grow at higher rates as a result of nutrient uptake.
•Groundwater is recharged & soil health is increased.
•Purification of air as a result of increased plant growth.
•Fully reclaimed use of nutrients that might otherwise be wasted.
•Due to the energy used for pumping and treatment, grey water
reuse may increase your carbon footprint

15. CONCLUSION
•Population growth and the increase in urban populations
are likely to stretch water demands in both large and
small urban areas. Among all of these current and
upcoming changes, grey water reuse has emerged as a
way to reduce freshwater use and install in the public an
awareness of water conservation.

16. Continue….
•Conclusions Based on these Forerunner Case Studies:
1.Grey water reuse systems are somewhat costly to
implement, so governments often need to subsidize the
costs of installation
2.In all of these case studies, grey water reuse systems are
mostly localized within urban areas
3.With the exception of Japan, grey water reuse systems are
mainly installed in private homes and are not a part of the
municipal water infrastructure
4.Public acceptance and understanding of grey water reuse
systems is necessary in order for the systems to be widely
and properly used in homes

17. REFERENCES
1.Waste water engineering: treatment and reuse by
Metcalf & Eddy.
2.http://aces.nmsu.edu/pubs/_m/m-106.html
3.https://courses.cit.cornell.edu/crp384/2009reports/
White&Chung_Gray%20Water%20Reuse.pdf
4.http://greywateraction.org/content/about-greywater-
reuse
5.http://www.thehills.nsw.gov.au/Greywater-
Reuse.html#.UWrTRcpD7IW