‘TERAFIL’ green technology- Low cost & sustainable water purification systems

S.KhuntiaChief Scientist & Head

Design & Rural Technology Department

Institute of Minerals and Materials Technology(council of Scientific & Industrial Research)

Bhubaneswar-751013E-Mail ID: khuntias@gmail.com

Innovation for masses: Innovation for masses: ‘‘TERAFILTERAFIL’’ water purification systemswater purification systems

TERAFIL media (disc) :Porous terracotta disc, made from

red clay (pottery clay), sand &

wood saw dust

Principles: Pores in Terafil,

created by saw dusts, separated by

ultra-fine clay walls, but connected

each other by capillaries (0.2 to 0.3

µm). Sediments, iron, bacteria

removed on top surface of Terafil

disc, and pH, tastes improves through

filtration without clogging its core,

resulting 5 yrs life of Terafil disc

TERAFIL water filter disc

5,000 lit/day Terafil plant in

Karnataka

Iron sludgeTerafil production

Low cost device for removal of Low cost device for removal of

excess iron from water along excess iron from water along

with turbidity and bacteria with turbidity and bacteria

without electricity & chemicals.without electricity & chemicals.

Domestic filer 5,000 LPD plant in Karnataka

Pores (without

direct connectivity)Cross section of Terafil

Distribution of silver

particles on micro-platelets

Impregnation of nanoImpregnation of nano--silver in Terafil disc: silver in Terafil disc: By ARCI, Hyderabad By ARCI, Hyderabad ( Not yet commercialized )( Not yet commercialized )SilverSilver loading :loading : 0.3 gm per 100 mm dia. Terafil candle 0.3 gm per 100 mm dia. Terafil candle

Silver leaching in product water :Silver leaching in product water : 0.01 0.01 –– 0.03 mg/Ltr0.03 mg/Ltr

(WHO : <0.1 mg/Ltr)(WHO : <0.1 mg/Ltr)

Removal of microRemoval of micro--organisms :organisms : 100 % ( ARCI 100 % ( ARCI -- Hyd.)Hyd.)

Capillaries

(connecting pores)

0.2 0.2 -- 0.3 0.3 µµmm

Silver Silver impregnatedimpregnated

‘TERAFIL’- Red clay filtration media (disc) For treatment of ground water:-Quality of product water:-�Turbidity : Within BIS limits�Bacteria : Within BIS limits�Iron : Within BIS limits�pH : Within BIS limits�Correction of pH for acidic raw water�Color & odor reduces drastically and improves taste.�Cost of product water: Rs.2/- per ton (considering total cost)�Life of Terafil filtration disc: 5 years�Life of Terafil stand-alone plant: 10 to 50 yr.

For treatment of surface water:-Mild chlorination (2mg/ltr. bleaching power) to getpathogen free product water from contaminated raw water.

Capacity: 1 lit/hr to 1,00,000 lit/day, (No scale-up limitation)

Waste management: Insoluble sludge

Rejection of water: Nil

Sludge removal: Top wash by water jets or scrubbing

Operation : Without electricity & chemicals

Maintenance: Almost NIL

TERAFIL water filters

Hypothesis for removal of soluble iron from raw water and increase of pH in product water during filtration

through TERAFIL clay media

Hypothesis : (Ref. : D. V. Halem, Master of Science Thesis, Faculty of Civil Engg.,

Delft University of Technology, Netherlands, November 2006)

(A)Removal of Iron:

• Clay minerals have a negative surface charge & its magnitude is relatively constant.

• Reactive surface of clay particles interacts with ions & molecules in aqueous solution.

• Interaction between negatively charged clay particle surface and cations in

top layer pore water generate an electric double layer, which is an important phenomenon for Ion exchange.

• Therefore iron from raw water is removed, and some other minerals from Terafil clay is released to product water, which results in increase of pH &

TDS of product water.

• Precipitation of iron oxide/ hydroxide occurs on top surface of Terafil disc.

(B) Increase of pH of product water:

• Release of ions of Calcium (Ca2+), Aluminum (Al3+), Monosilicic acid (H4SiO4) & Hydroxide (OH-) from Terafil materials into water responsible for increment of pH of product water.

• Many sorption mechanism & precipitation all results removal & release of metals from water, which is very difficult to distinguish.

Terafil based water purification Technology:Gravity FiltrationGravity Filtration::• Point - of - use: Domestic Terafil water filter (20 to 70 LPD)• Community Terafil water filter: 1000 to 1,00,000 LPD (No scale-up limitation)

• Removal of sludge deposit: manual scrubbing or water sprayer• Frequency of cleaning: once in 15 to 30 days, depending on

turbidity and iron of raw water.• Life: 10 to 50 yrs.• Low cost ( Rs.10/- to 12/- per liter capacity community plant with RCC chamber)

• Rs.2/- per ton product water• Domestic filter: Plastic chamber, Community filter: RCC chamber• Floor area: 1.25 sq.ft / 200 liter per day capacity: for community filter

Pressure filtrationPressure filtration::• On-line Terafil water filter: 100-200 lit/ hr (depending on turbidity)• Community pressure filter: 1000 to 10,000 lit/ hr• Automatic cleaning & removal of sludge from top surface of Terafil disc.• Life: 5 to 20 yrs (depending on materials of chambers)• Low cost ( depending upon material of construction of filter)• Rs.2/- per ton product water or less.• High capacity , compact and requires very less surface area.• Domestic on-line: Plastic chamber, Community filter: Stainless steel

Some TERAFIL based water treatment systems:Some TERAFIL based water treatment systems:

1.Domestic filter: Capacity: 50 lit/day

(Gravity filtration) Unit cost: Rs.500/-Life : 10 years

2. Ferro-cement Low cost filter:(Gravity filtration)

Capacity: 1,000 lit/dayUnit cost: Rs.15,000/- (piping extra)

Life : More than 10 yrs(Feeding of raw water:

piped supply preferable) Ferro-cement - Terafil Filter

3. Domestic on-line Filter: (Pressure filtration with Overhead tank)

Capacity: 200 lit/hr

Unit cost: Rs.2,000/-Life : More than 5 yrs(Auto-cleaning & require overhead tank for feeding raw water)

Terafil with plastic container

COMMUNITY TERAFIL WATER FILTER Capacity: 1,000 liter per day

1/2" TAP FOR

FILTERED WATER

1/2" DIA PIPE FOR AIR VENT(Placed below RCC slab)

2"

3ft

3ft

1" TAP FOR REMOVAL OF

SLUDGE

2"

3ft 6 inch

3ft 2 inch

SECTIONAL VIEW

3ft 2 inch ID

TOP LID

TERAFIL CANDLE

Filtered water

Raw water

Water spray through nozzle

4. Community on-line Filter: (Pressure filtration with Stainless Steel Chamber)Capacity: 500 to 5000 lit/hr

Unit cost: Rs. 50,000/- to Rs. 2,00,000/-Life : More than 50 yrs(Auto-cleaning & low pressure pumpfor feeding of raw water)

5. LLDPE Tank Terafil water purification plant:(Gravity filtration)Capacity: 1,000 lit/day Tentative unit cost: Rs.15,000/- (piping extra)Life: more than 10 yrs

(Feeding raw water: piped supply preferable)

6. Community Terafil water purification plant:(Gravity filtration with RCC chambers)Capacity: 5000 to 1,00,000 LPD

Unit cost: Rs. 50,000/- to Rs. 10,00,000/-Life : More than 50 yrs(Semi-auto cleaning & low pressure pumpfor feeding of raw water)

Community On-line

Terafil water filter

Community Terafil water filter with LLDPE Chamber

Inauguration of 25,000 Lit/ day

Terafil water purification plant by Director General of CSIR at IMMT, Bhubaneswar during March 2009

large capacity Terafil water purification plant for community applications ( 5,000 to 1,00,000 lit/day)

Community On-line Terafil water filter (5000 lit/ hr capacity)

Domestic On-line Terafil water Filter(200 Ltr/hr capacity)

Terafil disc

• Operates by overhead tank or pump• Auto- cleaning of sediments from Terafil disc

Removal of sediments by circular water jet sprayer

Nozzle

Water spray

through nozzle inside filter

• Capacity: 50 lit/day

• Containers: Polypropylene (food grade plastic)

• Nos. of Terafil candles: 3 (100 mm diameter)

• Rate of filtration: 4 – 5 lit/hr

• Life of containers: 8 – 10 yrs.

• Life of Terafil candles: 3 – 5 yrs.

• Unit cost: Rs.500/-

• More than 1,00,000 units disseminated in J&K, Sikkim, Himachal, Bihar, Arunachal Pradesh, Assam, Chhattisgarh, Jharkhand’Tamilnadu, Karnataka, Gujarat, UP, Odisha

etc at present.

• Plastic Containers produced by CIPET-GOI

centers at Bhubaneswar, Chennai, Ahmadabad & Luknow.

Lid

Top container

Terafil

Support ring

Bottomcontainer

Tap

DOMESTIC TERAFIL WATER DOMESTIC TERAFIL WATER

FILTERFILTER

More than 1,00,000 Sets of Terafil water filter used at present

Domestic ‘Terafil’ water filter (POU):

Terafil filter in slum and SC & ST houses in Orissa

Use of Terafil Water filter in primary schools in Jajpur Dist of Orissa

1,000 LPD TERAFIL water filter in schools under JALMANI

More than 50, 000 units in operation in various states

Community TERAFIL water filter in schools under JALMANI programme

Iron contaminated raw waterIron contaminated raw water

Terafil water filter with ferro-cement chambers in JALAMANI programme.

in schools of Odisha, installed by RWS&S, Govt of Odisha

Training of high level delegates of Arunachal Pradesh

on construction of 1,000 LPD Terafil water filter with pre-fabricated RCC rings at IMMT-Bhubaneswar

Cementing TERAFIL disc on middle plate

Deposit of Iron oxide sludge over TERAFILS

Removal of sediments from surface of Terafil disc (Top wash) through water sprayers : Semi-automatic operation.

5000 LPD Terafil water purification plants installed in Karnataka

Performance of TERAFIL water filters

10,000 LPD TERAFIL GRAVITY FILTER

Location: CSIR-IMMT, Bhubaneswar(Sept. 2010 – Oct 2011)

Iron from raw water adsorbed on Terafil surface and some minerals of Terafil clay released to product water during filtration, resulting to increase of pH & TDS of product water.

pH

Iron

Turbidity

TDS

RW

RW

RW

FW

FW

FW

RW

FW

1,000 LPD TERAFIL GRAVITY FILTER

Location: Utkal University School, Bhubaneswar under JALMANI

(Oct. 2009 – Oct 2011)

Iron from raw water adsorbed on Terafil surface and some minerals of Terafil clay released to product water

during filtration, resulting to increase of pH & TDS of product water.

pH

Iron

TDS

Turbidity

FW FW

FW

RW

RW

RW

RW

FW

Performance of 1,500 sets Domestic Terafil Water filters Installed in few villages of Odisha(August 2009 – September 2011)

pH Iron

RW

RW

FW

FW

Performance of domestic online Terafil water filters in

CSIR-IMMT, Bhubaneswar Campus( Aug 2009 to Aug. 2011)

Iron

pH

TDSTurbidity

FW

RW

RW

RW

RW

FW

FW

FW

Raw waterRaw water

FW FW (without chemicals): (without chemicals): LRV: 3

FW FW (from RW + 2 & 3 mg/lit Bleaching powder)(from RW + 2 & 3 mg/lit Bleaching powder)

FWFW (from RW + 1mg/lit Bleaching powder): (from RW + 1mg/lit Bleaching powder): LRV: 4

Total coliform count in Raw & Filtered water ( with/ without chemical treatment)

Total coliform in raw water

(treated with 2 mg/lit bleaching powder (30% Chlorine)

Total coliform in filtered water

(Raw water treated with 2 mg/lit bleaching powder prior to filtration)

Total Coliform count in Input water: 2.8 – 3.5 X 106 CFU/mlReduction through Terafil (without chemical treatment): 99.9% (Log10 Reduction = 3)

Reduction through Terafil ( Raw water treated with 2mg/lit Bleaching powder): 100%

Efficiency of removal of microorganisms by filtration through

Terafil disc (without chemical treatment )

• Contaminated raw water can be treated with 2 mg. / Ltr. bleaching powder followed by filtration through TERAFIL Water Filtration Media (Disc) to obtain pathogen free clean & iron safe drinking water.

• Excess iron & turbidity reduces significantly and pH increases substantially for purification of contaminated surface and ground water.

• Domestic & Stand-Alone TERAFIL water purification plant is efficient, affordable and sustainable for supply of drinking water without use of electricity in rural sector.

• Online Terafil water filters is an affordable and sustainable technology for instant purification and supply of clean drinking water for urban & semi-urban areas and for disaster management.

• Terafil water purification disc and filters can be easily produced by small and micro industries in each part of the country.

• Terafil water purification systems is a green technology which functions without chemicals & electricity for long period.

Conclusion:

Thank you

Save drinking water