Post on 06-Feb-2018
By
Dr. Virendra K. Vijay
Centre for Rural Development & TechnologyIndian Institute of Technology, Delhi
Hauz Khas, New Delhi, IndiaE-mail: vkvijay@rdat.iitd.ernet.in,
vkvijay14@hotmail.com
IITD
Biogas enrichment and bottling technology
for automobile fuel-IIT Delhi Technology -
Case study of goshala in Rajasthan
Introduction
Biogas is an important renewable energy resource for rural areas in India.
It is produced by anaerobic digestion of biological wastes.
It is an environment friendly, clean, cheap and versatile fuel.
Biogas generally comprise of 55-65 % methane, 35-45 % carbon dioxide,0.5-1.0 % hydrogen sulfide and traces of water vapour.
Average calorific value of biogas is 20 MJ/m3 (4713 kcal/m3).
Biogas like Liquefied Petroleum Gas (LPG) cannot be liquefied undernormal temperature and pressure.
Critical temperature required for liquefaction of methane is -82.1oC at 4.71MPa pressure, therefore use of biogas is limited nearby thebiogas plant.
An estimate indicates that India has a potential of generating 6.38 X 1010
m3 of biogas from 980 million tones of cattle dung produced annually.
The heat value of this gas amounts to 1.3 X 1012 MJ. In addition, 350million tones of manure would also produce along with biogas.
Organic Wastes & their Estimated Availability in India
Sr.
No.
Organic Wastes Estimated Quantity
1. Municipal Solid waste 30 million tons/year
2. Municipal liquid waste 12000 million litres/day
3. Distillery (243 units) 8057 kilolitres/day
4. Press mud 9 million tons/year
5. Food & fruit processing wastes 4.5 million tons/year
6. Willow dust 30000 tons/year
7. Dairy industry waste 50-60 million litres/day
8. Paper & pulp industry waste (300 mills) 1600 m3/day
9. Tannery (2000 units) 52500 m3 waste water/day
Source: MNES Report, Renewable Energy in India and business opportunities,
MNES. Govt. of India, New Delhi, 2001
Utilization of Biogas
Cooking: Biogas can be used in a specially designed burner for cooking
purpose. A biogas plant of 2 cubic metres capacity is sufficient for
providing cooking fuel needs of a family of about five persons.
Lighting: Biogas is used in silk mantle lamps for lighting purpose. The
requirement of gas for powering a 100 candle lamp (60 W) is 0.13 cubic
metre per hour.
Power Generation: Biogas can be used to operate a dual fuel engine to
replace up to 80 % of diesel-oil. Diesel engines have been modified to run
100 per cent on biogas. Petrol and CNG engines can also be modified
easily to use biogas.
Transport Fuel: After removal of CO2, H2S and water vapour, biogas can
be converted to natural gas quality for use in vehicles.
Biogas Technology Status
India has been pioneering country in developing simple and easy to operate
biogas plants.More than 4 million family type biogas plants have installed so
far.
The government of India has been running National Biogas and Manure
Management Program (NBMMP) for the welfare of the weaker section of the
society.
100% Biogas engines are in operation in the country.
95% methane to make it suitable to be used as a transport fuel and for
blending with natural gas where the gas grid is available.
From small to large size , large no. of biogas systems are in place across the
country - 1cum/day to more than 20,000 cum/day
and there exists large potential in this area
New Initiative by MNRE
BGFP Program: Demonstration of an Integrated Technology
Package on Biogas-Fertilizer Plants (BGFP) for Generation,
Purification/ Enrichment, Bottling and Piped distribution of
Biogas towards harnessing ‘Near Total Potential of suitable
Biomass in Rural Areas in India.
The Ministry of New and Renewable Energy support of 50% can be
made available for taking up such technology projects. Balance 50% of the
cost of the project is required to be invested/ mobilized by the
entrepreneur/ developer. However, at least 20% of the cost of the project
is to be met by the entrepreneur/user agency in case loan is availed from
banks/ financial institutions including NABARD and IREDA.
The capacity of BGFP could be 200, 400, 500, 1000 m3 biogas/ day and
multiples there of depending on the availability of suitable biomass feed-
materials and cattle-dung.
Need for the Biogas Refining and Bottling
Potential of biogas is not fully utilized and commercialized so far.
For commercialization, its area of application may widen; from cookingfuel to vehicle fuel/or transportable fuel
For use as a vehicle fuel, it should be bottled like CNG.
Before bottling, it should enriched in methane content from 55 % to 95%; similar to CNG.
Refining and Compression of Biogas
Purification is carried out to enrich biogas by scrubbing off the unwantedcomponents i.e. carbon dioxide (CO2) and hydrogen sulfide (H2S).
It is essential to have more energy per unit volume of compressed biogasand to get rid of the corrosive effect of H2S.
Various purification processes include absorption into water, absorptionby chemical, pressure swing adsorption and membrane separation.
One of the simple and cheap method is the use of pressurized water as anabsorbent liquid.
Design of Water Scrubbing System
Water scrubbing method is found suitable for biogas
enrichment in rural areas.
Water is good solvent for CO2.
The solubility of CO2 in water is governed by variation in
pressures and temperatures.
Approximate solubility of CO2 in water
Pressure
(atmo-spheric)
Solubility, kg of CO2 per kg of water at different temperatures.
0 ˚C 10 ˚C 20 ˚C 30 ˚C
1 0.40 0.25 0.15 0.10
20 3.15 2.15 1.30 0.90
50 7.70 6.95 6.00 4.80
Biogas Enrichment and Bottling System
11
Fig.1: Experimental setup for biogas purification and bottling
5
1
3
2
4
6 7
1-Biogas plant
2-Ball valve
3-Water remover
4-Receiver mounted compressor
5-Pressure gauge
6-Gas Storage Vessel
7-Rotameter
8-Supporting stand
9-Reshching rings
10-Scrubber
11-Safety valve
12-Water sprayer
13-Flange
14-View glass
15-Water outlet
16-Water pump
17-Gas filter
18-Pressure reducer
19-Three stage gas compressor
20-CNG Cylinder10
9
12
8
15
16
19
18
13
17
14
NOT TO SCALE
20
Success Case Study of Biogas as Automotive Fuel
Rajasthan Go Sewa Sangh, Durgapura,
Rajasthan: ( 50 years old NGO established for upliftment
of rural poor bycow and cow products)
More than 30 acre campus in Jaipur consisted of :
•goshala - 250 cows, 3 biogas plants
•naturopathy & ayurvedic indoor hospital,
•milk processing and medicine making units,
•products retail out let,
•biogas slurry drying and vermi -compost making
unit,
•agricultultural farm for organic vegetable & fodder
cultivation,
•Biogas Plants: 3 biogas plants
85 cum +60 cum+30 cum = 175 cum/day
•Biogas enrichment and power generation
started in July 2006
•Biogas bottling Plant started in Dec 2007
since then it has been running successfully.
A three wheeler runs on biogas daily about 100
km. and approximate 4 kg Bio-CNG is required .( Demonstration support from DST, Govt of India)
Produce locally and consume locally
for sustainability of resources on mother
earth - Mahatma Gandhi
Decentralised production and utilisation of
energy is the only solution for energy security
in rural areas
BIOGAS UTILIZATION
1.Automobile Fuel:
Three wheeler luggage carrier –runs 100-110 km/day on enriched
biogas
Till now run more than 12500 km on biomethane
2. Power Generation
100% Biogas Genset : 12 kW - 5 hrs/ day
Water pumping
Lighting in the complex
3. Thermal Application :
gas consumption for cooking in their naturopathy hospital kitchen and
Ayurvedic medicine preparations
KVIC/Jan0828
Comparison of Gaseous Emissions for Heavy Vehicles (Bus)
in g/km
CO Hydro Carbons NOX CO2 Particles
Diesel 0.2 0.4 9.73 1053 0.1
Natural gas 0.4 0.6 1.1 524 0.022
Biogas 0.08 0.35 5.44 223 0.015
Source: A report on biogas technology and biogas use in Sweden, Traffic and Public
Transport Authority, City of Gothenburg, November 2000.
Emission Benefits of Biogas
Possible entrepreneurial avenues which can have PoA- CDM benefits in Rural Areas with Biogas
Large Scale/ Community level Biogas Enterprises for
1. Cooking needs- Pipeline supply
2. Electricity Production and Supply
3. Rural sanitation & bio manure production
4. Cylindering of methane available from biogas plantfor tractors and rural vehicles and production ofbio manure
Large Scale/ Community level Biogas Enterprises forCooking needs- Pipeline supply and Rural Sanitation andbio manure production
I. Size of Biogas Plant- 85 m3/day No. of families Beneficiaries—50
Cow dung required—2 Tons/day- 250/Ton
A complex of 20 community toilets
Gas utilization—Cooking
If for Cooking – 2 hrs. morning & 2 hrs. evening(1.5 m3/familyper day)
Pipeline length—up to 1km. distance
Pipe quality—HDPE, pressurize system—0.3 kg./cm2(Rs. 2.5 lacscost)
Gas charge—150/month-family
II. Raw material—Cow dung+ Toilet (community-20 toilets costs 1.5lacs)
III. Slurry Management—Biogas digested slurry
Four options-
1. Liquid slurry
2. Recycle water (upto 40 to 50% only)
3. Dry slurry
4. Semi dry
•Local consumption of slurry is advised
•Quality of slurry should be maintained
Cost estimates
Non- recurring cost—Rs. 8,20,000 ($ 20,500)
Recurring/ Variable cost—Rs. 2,12,000 ($ 5300)
Manpower-- Rs.96,000 ($ 2400)
Depreciation—Rs.80,000 ($ 2000)
Sum of recurring cost- 3,88,000 ($ 9700)
Revenue generation- 5,90,000-3,88,000=Rs.2,02,000 (& 5050)
Note- In addition to this Carbon credit benefit to thetune of Rs.71,000/yr. ($ 1775) will also be available.
Large Scale/ Community level Biogas Enterprises for Electricity
Generation and supply for domestic consumption, water supply and
community consumption and Rural sanitation
15 KVA Power Generating System from - 85 m3/day Biogas Plant
No. of families Beneficiaries—50
No. of Animals—200
Cow dung required—2 Tons/day- 250/Ton
Gas utilization— Electricity
Domestic connection—2CFL, 1 Fan= 100 Wt.*50=5000Wt.
Water supply connection—4000 Wt.
Community Hall—2 CFL, 2 Fan & 1 TV.= 500 Wt.
Cost estimates
A. Non recurring
Sum =8,50,000 ($ 21,250)
B. Recurring
Sum=3,87,000 ($ 9675)
Income—
Electricity supply 130 unit @ Rs.6 per unit *365 = Rs.2,84,700/yr. ($7117)
Slurry—Rs.1500/day= Rs.5,00,000/yr. ($ 12,500)
CDM benefits – Rs.71,000/yr. ($ 1775)
Sum= Rs.7,84,000 ($ 19,600)
Surplus—
Rs. 7,84,000-3,87,000= Rs. 3,97,000 ($ 9925)
Cylindering of methane available from biogas plant
for tractors and rural vehicles and production of bio
manure
Biogas plant of 300 M3 per day capacity with enrichment and bottling
CAPITAL COST – Rs. 28,00,000.00 ($ 70,000)
OPERATION COST –
A. Fixed operational cost-3,00,000 per annum ($ 7500)
B. Annual Running (Operational) Cost: -12,00,000 per annum
Total cost of Operation = Rs. 15,00,000 /- ($ 37,500)
Income:-
income generate by selling CBG and slurry = Rs. 22,00,000/- ($ 55,000)
Profit = Rs. 7,00,000/- ($ 17,500)
Payback Period = 4 years
Advantages of this biogas
programme under PoA-CDM
Reduction of methane & CO2emission from cattle dung
Replacement of diesel/petrol by enriched Biogas in
vehicles/ pump sets
Replacement of LPG/ biomass/ kerosene from biogas for
cooking needs
Electricity
Issues: Monitoring
Verification
Conclusions
India has second largest biogas programme in the world at ruraland as well as urban levels.
Technologies/models have been successfully developed forbiogas enrichment and bottling for automobile applications inIndia
There is need to develop a sustainable renewable energyprogramme on biogas for replacing petroleum products byutilization of biogas in the country as commercial enterprises.
This will help in green energy technology and reducing greenhouse gases emissions.There is good scope of taking it underPoA- CDM activity.