Minakshi Bagde CSIR-National Environmental Engineering Research Institute

Nagpur, India

“Grey Water Treatment and its Reuse using Vertical Wall System”

International WaTER Conference

on

University of Oklahoma, USA September 21-23, 2015

Elementary Highlights

• Background

• Domestic Water consumption pattern in India

• Necessity of Grey water reuse

• Assessment of Grey water generation

• Characterization of Grey Water quality

• Methodology & approach of treatment

• Results & Discussion

• Conclusions

• Future prospects

__________________________________________________

Background

In 2005, 65% of major cities in India- water deprivation and famine in

land availability.

Water conservation - reusing of wastewater by possible treatment to keep

usage and also ensure future availability of resources

_______________________________________________

The world’s six billion people are appropriating

54% of all the accessible freshwater contained

in rivers, lakes and under-ground aquifer

(source: http://www.unwater.org/statistics.)

54%

.

Today’s desire to design green systems,

following concern factors are:

o Reduce the fresh water demand

o Carbon footprint area

o Control temperature

o Social and Economic needs

Reuse technology is increasingly being advocated as a new ‘solution’ to meet

water demands

0

5

10

15

20

25

30

Domestic Activities1

Domestic Water Consumption in India 2050E(%)

Other Cooking Drinking

House Cleaning Washing utensils Washing Clothes

Toilet Bathing

Domestic Water Demand V/s rise in Urbanization

34%

45%

61%

2007 2025E 2050E

Urban Population as a % of Total Population

Note:- Water Poverty in Urban India: A case study at major cities

Note:- Central Pollution Control Board :

India’s water future in 2025-2050;

Urban and Rural areas 2007 “Water Supply-The Indian Scenario”

________________________________________________

Necessity of Grey water Reuse

*India sinking into water stress at current usage levels

Impact on Water Stress*

Domestic contribution to the total water

consumption is projected to increase from

5% in 2000 to 11% by 2050.

It is estimated that by the year 2050, close

to 80% of the world’s population will live

in urban areas and the total population of

the world will increase by 3 billion people.

Per capita water consumption is

expected to double from 89 liters/day in

2000 to 167 liters/day by 2050.

54%

_______________________________________________

Note:- *Dreaming with BRIC’s-” The Path to 2050, Goldman Sachs,2003; “IEA – Status of Water treatment plants in India”

3%

[PERCENTAGE]

[PERCENTAGE] [PERCENTAGE]

Grey water 62%

Total Water Consumption

Drinking water Toilet flushing

Gardening Washing & Cleaning of house

Grey Water

49%

7%

27%

17%

Grey water Production

Shower and Bath Hand Basin

Laundary Kitchen

Ref. Ghunmi 2009; Lin et al. 2005; Jefferson et al. 2004; NEERI 2007

Waste water reuse technology is at higher demand to conserve water. On reuse point

grey water plays important role for water conservation, which is less polluted when

compared with black water (toilet, faeces).

Hence, can be successfully treated and reuse for non-potable purposes.

Necessity of Grey water Reuse _______________________________________________

Assessment of Grey water generation ___________________________________________________

It is observed that swimming pool

requires substantial quantity of water

particularly for bathing of users

before and after the use of pool. This

indirectly leads to grey water

generation.

(21.119397,79.066232)

Location @ NEERI, Swimming pool premises

for implementing Grey water treatment system unit • Number of users – 5-20 persons/day (winter)

40- 80 persons/day (summer)

• Total Grey water generated (shower) – 500-

4000 lit/d, approx.

Vertical Wall System……..??? ___________________________________________

“Wall Treatment system” in minimal spatial area to treat

grey water by using indigenous and inexpensive material

through linear wetland or bio-filtration

The system also called as green wall/ bio-wall/vertical

garden

A new innovative, yet environment-friendly , light framed

and self–supporting plant

Based on the principles of hydroponics.

Plants receive water and nutrients from within the vertical

support instead of from the ground.

Key components of system _______________________________________________

Dimensions of Pot: Length –11.5 Cm,

Width –1.5 Cm,

Height –12 Cm

Properties:

Low weight

High tensile strength

Good UV resistance

Uses:

Flexible

Stackable containers

Indoor and Outdoor use

1. Vertical Panel Frame

Material: Recycled Polypropylene with

UV Stabilizer

2. Light Weight Expanded Clay Aggregate

(LECA)

Leca is a light weight aggregate made by heating clay

to around 1,200 °C (2,190 °F) in a rotary kiln. LECA is

imported in India by GBC INDIA. Gradation: 0-4mm

Properties:

Light Weight:

Density of aggregates

(380-710 kg/m3 )

Water Absorption

(0-25 mm) is about 18%

of volume in saturated

state during 72 hours.

Filtration

Used as a growing

medium in

hydroponics systems

as treatment facilities

for the filtration and

purification of

municipal wastewater.

Thermal insulation;

Sound Insulation;

High Durability

Leca wide availability: Light Weight Concrete, light weight block, Prefabricated Panels & Slabs.

Light Filler, Leca Mortar and Water Purification.

3. Plants

Syngonium

Dwarf Canna indica

Asparagus Sprengeri

Alternanthera Green

The selection of the plants is a technical criterion of utmost importance because determines:

Alternanthera Versicolor

_____________________________________ Methodology

Feeding System

Vertical Wall Frame(Size 150X450cm)each consist with 3 no.pots

0.10m0.10m

0.45m

0.15m

Grey Water Inlet

0.45m

Ground Level

Treated Grey water Collection Tank (Cap. 90 litre)

Degreaser (0.9X0.9X0.3m) (inner dimensions)

Sump 2

Towards Gardening

Overflow pipeSump1

P

0.8

0 m

Discharge Pipe

8mmØ

10mmØ

Grey water CollectionTank (100 Litre cap.)

3"Ø

Asparagus

Sprengeri

Alternanthera

Versicolor

Alternanthera

Green

Experimental Setup at Swimming pool premises, NEERI _______________________________________________

Phytodepuration Filtration Proposed Treatment mechanism:

“Water dripping down through the vertical displacement will sustain the plants and at same

period wastewater will be purified by forming treatment mechanism”.

Commissioning of System Characteristics of Grey Water

_______________________________________________

Parameters Units Concentration

pH - 8.1-8.5

TSS mg/L 20-36

BOD mg/L 90-120

COD mg/L 150-200

Oil & grease mg/L 20-25

Alkalinity mg/L 110-130

Key Findings

o Fresh water demand is regularly in use for non-potable purpose (gardening)

o To reduce the fresh water demand – Initially 5 L of grey water was fed in the treatment

system to nourish plant.

o After 1 week - 10 L of grey water was fed to the system, which indicated potential of

plants to treat grey water (above table)

o Looking forward to this, 100 litre cap. of grey water would be fed in coming 15-20 days

__________________________________________________ Results & Discussion

Fig. Grey water quality parameters through the treatment system Inlet (Raw Grey water) & Outlet (Treated Grey water)

Grey Water Quality Parameters

Sr. No Parameters Inlet (Raw) Outlet (Treated)

1 pH 8.4 8.25

2 Alkalinity 124 114

4 BOD 115 92

5 COD 192 152

7 Oil & Grease 24 22.5

8 TSS 36 24

10 TC (cfu/100ml) 480*103 460*103

11 FC (cfu/100ml) 80*103 30*103

*All parameters except pH are in mg/l

0

20

40

60

80

100

120

140

160

180

200

Alkalinity BOD COD Oil & Grease TSS

Val

ues

in m

g/l

ex

cept

pH

Inlet (Raw) Outlet (Treated)

Sr. No

Description (100L cap.) Amount ($ US)

A Vertical Wall Component 438

B Civil Work 159

Total 597

Say 600 $

In words: (Six Hundred Dollar only) approx.

Wall area required : 1.25/m2 for 100 Litre cap. (approx.)

1000 L cap. Wall area required (approximate) = 15m2

Tentative Cost = 2365 $

Estimate Summary for Vertical Wall of Capacity 1000 lit/day. _________________________________________________

Conclusions……… _______________________________________________

Minimal spatial footprint area, makes this design attractive for urban

development.

The reduction of weight was achieved with the use of lightweight substrates

(LECA)

Water Treatment Efficiency with Hydraulic loading rate = 67 lit/m2/day

(approx.)

Good overall treatment performance with average removal of solids (TSS) and

organic compounds (BOD3 and COD) within the expected range

29%-43% saving on

fresh water consumption

Improved air quality,

thermal insulation,

temperature control and

acoustics

Adds aesthetics of

locality and socio-

economically

sustainable

Future Prospects…..

Acknowledgement _____________________________________________________

National Environmental Engineering Research Institute

(NEERI), Nagpur

Dr. Girish. R. Pophali

Dr. Pawan. K. Labhasetwar

Council of Scientific & Industrial Research (CSIR)

The University of Oklahoma, Norman, U.S.A

Minakshi Bagde :

minakshi.bagde@gmail.com