Grey Water Recycling

With ever increasing population the need to provide adequate water for household purpose is becoming an acute problem. One way to solve this problem is to recycle the used water and recharge the ground water with rain water and reclaimed water.Reuse of such water reduces the need for augmenting additional supply from scarce water resources.Natural resources such as water have been under over exploitation since the beginning of the civilization. Water is becoming scarce commodity and it is becoming expensive to provide for human habitation in both rural and urban areas. While we have the right to the resources, we have the responsibility to replenish, conserve and preserve the natural sources for future Generations.

Briefly the Objectives are:
i) To Conserve Water by Recycling of Grey water
ii) To promote usage of reclaimed water to reduce the demand for more water
iii) Safeguard and increase Ground Water levels
iv) Generating recycled water for Bath rooms, toilets and other purposes within the habitation
v) To make Hyderabad as Model city in the usage of reclaimed  water
vi) Increase Ground water level by recharging with rain water & reclaimed Water
vii) Involve citizens as partners in making Hyderabad as model city
viii) To save power by avoiding the use of excessive pumping of ground water

Provisioning clean water and improved sanitation to the billions who lack them is “not a question of money, it’s not a question of technology, it’s a question of governance, of commitment, will—all of those things. And that, in many ways, is the worst part of the world’s water crisis,” said Peter.H.Gleick, president of the Pacific Institute.

It is estimated that 15% of world wide water use is for household purposes. These include drinking water, bathing,cooking, sanitation, and gardening.Basic household water requirements have been estimated by Peter Gleick at around 50 liters per person per day, excluding water for gardens.

Strategies to Conserve Water
Two main Strategies are based on recycling of Grey water and to increase ground water levels which are cost effective,easily
implementable, sustainable, maintenance free; further the Government need not invest any tax payers money for this purpose.The only requirement is the solicitation of commitment from the public. This Can be implemented not only in Hyderabad city, but also in any larger human habitat.

Grey Water Recycling
Grey Water is the water used in the houses – Bath rooms,Washing Machines, Dish Washers, Kitchen sinks except the
water used in Toilets.Recycling of Grey water is costly, requires the treatment by adding antibacterial agents and disinfectants, water samples are to be taken at regular intervals for inspection, as it contains food particles and other organic material a rich source of substrates for microbes. The Proposed GREY WATER for recycling contains exclusively bathed water, washing-machine water and bathroom cleaned water only, consists of disinfectants, deodorants, and other aromatics along with some solids like debris, and undissolved particles. It does not contain any effluents coming from dish washers and kitchen sinks.

Brief Description of Grey Water recycling

Collection of Grey Water to a HDPE Tank-A (shown in Figure-1) placed at basement or cellar. Water enters through PVC filter (shown in Figure-2) to separate solids which can be drained out to Sewage Water line whenever required.

Legend: Figure-1
Flow Direction of Grey Water (From Bath Rooms)
Flow Direction of Reclaimed Water (To Flush etc.)
Flow Direction of Black Water (From Toilets)
X- Source of Grey Water (Bath Rooms, Wash Areas)
1- Grey Water Collection Pipe to Tank-A
2- Control Valve for Grey Water to Tank-A
3- Sludge/Debris Delivery pipe to sewage pipe line (Tank-A)
4- Control Valve for Sludge disposal from Tank-A
A- Grey Water Receiving Tank with Filter Cartridge
5- Filtered Clear Water Connection from Tank-A to Tank-B
6- Sludge/Debris Delivery pipe to sewage pipe line (Tank-B)
7- Control Valve for Sludge disposal from Tank-B
B- Filtered Reclaimed Water Storage Tank (Tank-B)
8- Reclaimed Water (RW**) usage Control Valve
9- RW** for Cleaning Premises, Car wash etc
10- RW** out-let for Pumping to Tank-C
11- Motor to pump RW** to overhead Tank-C
RW** - Reclaimed Water

12- RW**Pipeline to Overhead Tank-C
Y- Toilets where the Grey Wa ter can be used for Flushing
13- RW**Out-let for Cleaning Premises, Roof
Garden etc.,
14- Control Valve for Rw**
15- Air out-let to avoid airlock
C- Overhead Storage Tank for RW**
16- Excess RW** to sewage pipe line
17- Rw** for Flushing Toilets
18- Black Water Out-let from Toilets to Sewage Pipe line
19- Sewage pipe line.

Further filtration will be done through Filter Cartridge (Figure-2)  Placed in Tank-B.Add appropriate chemical pigment such as “HARPIC” (Manufactured in India by M/s.Reckitt Benckiser (India Ltd).Okhla New Delhi) to the reclaimed water for marking and detecting. Pump the pigmented reclaimed water to a Separate overhead Tank-C. Water collected into Overhead Tank-C, is now useful for non-potable usage like flushing, cleaning the premises, car washing and gardening etc.,Clearing the residue and debris to the Sewage pipe line when ever required from Tank-B. If more water is needed another sub storage Tank can be provided.

Detailed description of Grey Water Recycling

Step1.
Collect Grey Water from bath-rooms and wash area through a separate pipeline. The pipe line should be coloured lilac/purple
Red PVC (Polyvinylchloride) for easy identification from potable water line, and black water line, to a HDPE (high density
polyethylene) Tank-A placed in the basement or cellar. (Shown in Figure-1)
The Grey Water will reach the filter Cartridge in Tank-A Having Three layer filter where Water will be filtered, separates solids
which can be drained out to the sewage pipe line. Grey Water free from solids reaches Tank-B.
Connections of tank-A.
1. One inlet for Grey Water to reach filter Cartridge
2. One outlet to Tank-B
3. One outlet to Sewage water line to remove Debris
Step2.
The Water reaches the bottom chamber of filter Cartridge in Tank-B, Having Three layer filter where Water will be filtered;further, solids and debris etc will be collected here and can be cleared out to the Sewage Water line whenever required.The clear water rises in to the cartridge (Figure-3 Cross section) containing small chips of black stone at bottom as first layer,Second layer of rough Sand finally the top layer of fine sand,and then the clear Water enters the Tank-B through the minute filter holes of filter Cartridge. This clear water can be used for other purposes like flushing, washing premises, car washing, Gardening, Curing for the new constructions etc., Since the surplus reclaimed water will be more than required quantity for flushing etc., surplus water can be collected and supplied to the car washing sheds, Parks, fountains , divider lawn wetting, and curing for the New constructions if properly organized. If this process is adopted ground water can be saved from extraction which in turn saves lot of power.

Connections of tank-B.
1. One outlet to the pump Motor
2. One outlet to the reclaimed over-flown water to Sewage Water line.
3. One outlet (optional) to the basement cleaning or car wash or gardening purpose.
4. One outlet for air to avoid air-lock.
Step3.
We can add coloured microbiocide agent to give colour to the water for identification, fragrance also can be added if required.
This process is also useful for identification of any leakage in the pipeline because of the pigment added.

Step4.
Pumping Motor will pump the water from Tank-B to Over head
Tank-C located at terrace.
Step5.
The reclaimed water from the overhead Tank-C connected to flush tanks with a separate coloured (Lilac/purple red) pipe line.

Connections of Tank-C.
1. One Inlet for the pump Motor
2. One outlet for the flush tanks.
3. One outlet (optional)for cleaning terrace and other premises, roof Garden etc.,
4. One outlet for air to avoid air-lock.

Frequently Asked Questions