About Biodigester Technology Special Features

Anaerobic microbial inoculum

Cold tolerant microbial consortium

Required one time inoculum charging

Immobilization matrix for retaining higher microbial mass

for survival in adverse conditions

Specially designed tank for efficient biodegradation

Suitable for mobile and stationary platforms

Permits use of toilet cleansing agents

Advantages

Tailor made in respect to number of users, materials,

situation and condition Eco-friendly & cost-effective

Wide applicability under different climatic conditions

Customized & easily adaptable

Maintenance free

Minimizes water consumption

Recycling of effluent water

Reduction in organic waste by more than 90%

More than 99% pathogens reduction

Generation of odourless and inflammable biogas

Human Waste Disposal

UNDECOMPOSED HUMAN WASTE * AESTHETIC NUISANCE * INFECTIOUS DISEASES * ORGANIC POLLUTION OPTIONS * TRANSPORTATION * INCINERATION * CHEMICAL TREATMENT * BIODEGRADATION (AEROBIC/ANAEROBIC)

Twin-Pit Pour-Flush Toilet (Leach Pit Toilets)

The pits are constructed in brick line (much like a honeycomb to facilitate the liquid to flow out) or with perforated concrete tubes (e.g. pre-fabricated)

A wooden or concrete slab to prevent people falling into them

The pit shape can be circular or rectangular, but circular pits are more stable

Pits should be placed symmetrically at the back of the latrine pan and have a minimal distance of the pit depth to prevent cross-contamination.

If the spacing between the two pits is to be reduced, an impervious barrier should be provided between them

Courtesy: SSWM

Distance not

less than the

pit depth

Junction /

Inspection

chamber

Adapted from

http://www.k4rd.or

g/ruraltech_pit.htm

[Accessed:

01.06.2010]

PRESENT SEPTIC TANK SYSTEMS :-

BIGGER VOLUME

REQUIRES LARGER SPACE

COSTLY TO BUILD

NOT EFFICIENT

OBNOXIOUS SMELL

MAINTENANCE INTENSIVE

UNHYGIENIC DISPOSAL

SEPTIC-TANK (Conventional technology)

17-04-2015

Percentage of Households Having No Latrine India, 2001-2011

6

10.5 % improvement in

10 years

Bio-toilet BACTERIA (INOCULUM) Anaerobic microbial consortium

developed by acclimatization / enrichment of microbes at low temperature and bio-augmentation with critical group of bacteria

BIO-TOILET Fermentation container made of mild steel / SS / FRP / bricks.

The dimensions and internal design varies with no. Of users, water availability and geo-climatic conditions

Variants of Biodigester

Biodigester

Biodigester for mobile vehicles

Stationary Biodigester

For Armed Forces

For Civil application

For Indian Railways

For Snow Bound

Regions

For Soil Bound

Regions

For coastal areas

(Lakshadweep)

For cold climates

(Laddakh)

For House

Boats

Bio Digester for Plain areas

FRP Tank 700 Liters for 10-15 Peoples Mobile Toilet

Household Bio toilet

Design of Low Cost Biotoilet

FRP tank of 6 mm thickness.

Diagonal partition wall of 4 mm thickness

(adequately stiffened by ribs).

Tank is buried 700mm deep, and anchored by

300mm long stainless steel (SS316) anchor bolts at

corners.

Tank Internal Dimensions 1000x1000x700

(lxbxd).

Provision of water sealed outlet from the tank.

How a Digester functions

Aerobic vs. Anaerobic Biodegradation

Aerobic biodegradation Anaerobic biodegradation Forced aeration/ agitation is essential which is energy intensive

No aeration is required

Incomplete/ partial aerobic condition leads to foul smell Complete anaerobic conditions

Not effective in pathogen inactivation More than 99 % Pathogens inactivation

Can not tolerate detergents/ phenyl Anaerobes can degrade detergents/ phenyl

Generates large amount of sludge Sludge generation is very less

Repeated addition of bacteria/ en%ymes are required One time bacterial inoculation is enough

Maintenance & recurring cost is high Minimal maintenance & no recurring cost

STEPS IN ANAEROBIC DIGESTION

Hydrolysis

Acidogenesis

Acetogenesis

Methanogenesis

Large polymers are

converted into simpler monomers

Simple monomers are converted into

volatile fatty acids

Volatile fatty acids are converted into

acetic acid, CO2 & H2

Acetate & H2 are converted into

CH4 & CO2

Robust

Sensitive

14

Anaerobic Biodegradation

15

Advantage of anaerobic processes

1. Less energy requirement as no aeration is needed

0.5-0.75 kWh energy is needed for every 1 kg of COD removal by aerobic processes

2. Energy generation in the form of methane gas

1.16 kWh energy is produced for every 1 kg of COD fermented in anaerobic process

3. Less biomass (sludge) generation

1. Anaerobic process produces only 20% of sludge compared with aerobic process

2. Complete anaerobic degradation of 1 kg COD produces 0.35 m3 CH4 at STP

3. COD of pure night soil 100 150 g 02/ Kg

4. Night Soil per person 300 400 g based on food habit

Biodegradable Anaerobic process

COD 1 kg

CHd gas > 0.9 kg

New biomass < 0.1 kg

Laboratory Findings

DEVELOPMENT OF MICROBIAL CONSORTIUM

Screening & gradual adaptation

Isolation of psychrophilic bacteria from Antarctica/ Siachen

BIOAUGMENTAION OF MICROBIAL CONSORTIUM

VFA degrading bacteria

Psychrophilic proteolytic bacteria

CHARACTERIZATION OF MICROBIAL CONSORTIUM

HRT (25 days at 10°C)

Temp range (5-50°C)

Freeze-thaw resistance (two cycles)

PROCESS ENHANCEMENT

Immobilization

CaCO3

Sulphate

17

Comparative Biogas Production

of Different Feed Stocks

S No Type of feed stock Gas Yield per Kg ( m3)

1 Cattle dung 0.036

Human excreta 0.07

3 Horse dung 0.045

Sheep dropping 0.042

5 Camel droppings 0.056

Piggery waste 0.08

7 Poultry droppings 0.062

Wide variation in temperature: -50oC to 50oC

Variety Of Terrain: High Altitude, Hilly, Plains, Coastal Areas & Islands

Water Conditions: Low / High Water Table Dry / Flooded / Water Logged Areas Sweet / Salty Water

Economic Constraints, Awareness, Casual Approach Lack Of Concern

Waste Treatment Challenges

No energy dependence

Affordability

Long lasting (at least 15 years)

Require minimum water for cleaning

Space constraints

All weather system

Allow use of toilet cleaning agents for better hygiene

Free of manual scavenging / evacuation and Maintenance

DRDO Bio-Digester addresses all above challenges adequately

Challenges In Rural Sector - Plains

20

Biodigesters Installed in Plains

DRDE, Gwalior Vivekananda Needam, Gwalior

Games Village, New Delhi Model Town, New Delhi 22

Constructed Bio-toilet ,Gwalior

Various Models of Biotoilets

Types of Biodigesters

Installation of biodigester

Installed one biodigester at Parmarth Nikatan Aasharam , Rishikesh

Capacity : 4M3

Detergents/ Antiseptics for Cleaning

Phenyl upto

84ml/l

Harpic upto

250ml/l

Domex upto

250ml/l

TASKI R6 upto

250 ml/l*

TASKI Duck fresh upto

250ml/l*

TASKI Clonet

W4 upto 100ml/l*

TASKI MM65 upto

100ml/l*

TASKI MM60 upto

250ml/l*

Routine toilet cleaning agents available in market are compatible with Biotoilet

PRINCIPLE

Biodegradation of Human Fecal Matter by Microorganisms in Absence of Oxygen HUMAN WASTE METHANE + CO2+ WATER

(BIOGAS)

COMPONENT OF THE TECHNOLOGY

• Consortium of acclimatized microorganisms(Adaptive) • Bacteria immobilization Matrix(culturing surface) • Reaction Vessel • Reed (Plant)Bed for secondary treatment of water (Optional)

STEPS

BIOTANK CUM REED BED: TECHNOLOGY

• On-site construction • Design and construction very simple

(masonry work, brick wall/ RCC structure). • The size of the Bio-Tank: approximately 1/3rd

to 1/10th of conventional septic tank • Less space requirement • Low material/ construction cost • Can be of different sizes, either for single

house or multi-storeyed complexes as per the requirement

• Maintenance free

Biotank Cum Reed Bed System

(Tap water here!)

Water Quality

Water Quality

BioTank cum Reed Bed system

DRAIN (Semi Solid/ Sludge)

Sewage Treatment Plant (STP)

Polluted/ Untreated Water from STP

Conventional Drainage System

Polluted rivers

Bio-Digester: Flush & Forget Drainage System

• No STP

• No Manual Scavenging

• Helps in Cleaning River

Clean Water from Bio-Toilets

Clean Effluent Water

Bio-Digester

Tank

Bio-Digester

Tank Bio-Digester Tank Bio-Digester Tank

Community Bio-Toilet Complex

Clean & Green Drainage System

Bio-Digester

Tank

Water quality

Parameter Raw Water (WHO)

Septic Tank Biodigester/ Biotank

Biotank + Reed bed treatment

pH 5.5-9.0 6.7-7.5 7.0-7.2 7.0-7.5

Turbidity (NTU) 1000

500-800 70-90 2-5

Total Suspended Solids (mg/L)

- 150-300 90-120 50-80

TDS(mg/L) 1500

500-850 350-450 100-300

VS (mg/100mI) - 50-60 20-30 5-12

COD (mg/L) 10

1200-2000 250-300 15-25

BOD (mg/L) 6

350-500 70-120 2-4

Coliforms (MPN/ml)

5000 >3000 300-350 0-12

Oral toxicity at 0.5% of effluent ➢Acute toxicity ➢Chronic toxicity

Extensive studies on animal models conducted No clinical signs such as excitability, CNS stimulation, uncontrolled urination, bulging eyes, depression observed No change in biochemical parameters No toxicity found in both rat and fish models (Report: DRLT/PT/Tech Report-Biodigester /01 /2012, May 2012)

Effluent Safety Studies FRP Tank 700 Ltr for

5 – 6 persons

DRDO bio digester - Key benefits Zero maintenance No need to evacuate the digester tank at all as NO SLUDGE is formed All faecal matter completely digested and converted into water, methane ( bio gas) and CO2 Bio digester tank sealed tank construction - no mixing with ground water When implemented in SATURATION MODE and at every household, saves huge cost to Govts in design of city/municipal drainage systems (small drain pipes, less labour) Rivers, lakes and water bodies will become clean on its own in a short period - as raw sewage do not enter Huge cost saving for govt on health care especially towards BPL families that depend on open source water No need for STP as effluent from BIO DIGESTER is "safe"

Inauguration at Orissa

36

Bio Digester

“I was very happy to learn that DRDO in collaboration with FICCI has

commercialised bio-toilet that promises to solve the problem of open

defecation in rural India. If this green, cost effective “flush and forget”

technology is successfully implanted, it will give a big boost to our Total

Sanitation Campaign. Application of technology to social benefit

programmes should be expanded further.”

PM’s Address at DRDO Award Function (July 2012)

38

Current Status of Biodigesters Installed so far

High Altitude Low Temperature Areas: 166

Indian Railways: ~4000

Plain areas: 58 + 1500 (Lakshadweep)

Current Status of Bio-toiltes/ Biodigesters

Curent/ Future Assignments

UT of Lakshadweep: 12000

Ladakh Autonomous Hill Development Council: 750

UT of Daman: 50

Shri Amarnathji Shrine Board

Biodigester Locations

Significant Highlights

:* Patents

:* Granted: 7 (2 foreign)

:* Filed: 8 (2 PCT)

:* Publications: 29 (18 foreign)

:* MoU: 4 (Indian Railways, BMTPC, MDWS, GAP-FICCI)

:* ToT: 53

:* Defence Technology Spin-off Award-2007

BEC Fertilizers (Unit of Bhilai Engineering Corp. Ltd.)

Bilaspur Division, Sector A Sirgitti Industrial Area BIlaspur (C.G.) 495004

Ph: 07752-261180,262826.261909

Email: becfert@yahoo.com