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Biogas – not just cow power or poo power - it is renewable natural gas

Many of us consider biogas as just gobar gas or poo power. We can extract many times more energy from other biodegradable wastes than that from cow dung. For example, 1 kg of food waste when decomposed in an anaerobic environment yields 160 litres of biogas whereas non-edible oil seed cake produces 242 litres and bagasse gives 330 litres in the place of 40 litres of cooking gas with same weight of cow dung under similar conditions.

Biogas has vast potential as a sustainable renewable energy source.  Biogas is poised to lead the biofuel race owing to its advantages over the others.  When other biofuels require specific energy crops which may seize food crops or agricultural land, biogas can be generated from different biomass available – municipal waste being the most attractive option. After producing biogas, the anaerobic bacteria provide us a very good fertilizer whereas some other biofuel generation processes discharge toxic wastes. Utilisation of agricultural & other wastes as a resource and the value of the bio-fertiliser are significant for a country whose economy is depended on agriculture. Moreover, the energy content of biogas is higher than that of other biofuels extracted from biomass grown on a unit area. Some studies show that the average ethanol production from cereals and sugar cane crops is 2,400 litre of oil equivalent per hectare. Under the same conditions biogas delivers 4,500 litre of oil equivalent.  

Biogas consists mainly of methane along with carbon-dioxide and hydrogen-sulphide.  Purified biogas or biomethane being very similar to natural gas, it can be mixed with or substituted for the latter (called bio Natural Gas) in vehicles or other applications. In other words, biomethane can directly utilize the natural gas infrastructure.  In countries like Germany, biomethane is already being injected into their natural gas grids.

Biomethane is the cleanest fuel after hydrogen produced from water using solar or wind power.  Hydrogen to be used in fuel cells can be produced from methane also. But the recent technological developments allow the direct use natural gas or biomethane in the fuel cells with reduced cost of operation. Fuel cells, being more energy efficient, reliable and less polluting than other electricity generation methods, can be used in distributed power generation or in vehicles.

The transmission loss, cost of energy storage and transmission are very less for biomethane even compared to electricity as a long distance energy carrier.  The cost of building up natural gas/biomethane pipelines is said to be half that required to build electric transmission lines for the same quantity of energy transmitted. Biogas production at source of biomass will be convenient rather than transporting the biomass elsewhere for generating electricity. Besides all these, if waste heat from decentralised power generators can also be used, we could utilise up to 85% energy of the source compared to 30% energy reaching the users in the case of coal based power plants.

It is projected that by 2050 global primary energy demand will be 1014 EJ (Exa Joules) whereas the total biomass alone has an energy potential of 1,135 EJ without affecting food production.  Sweden is already using biogas to meet 25% of its energy requirement with majority being used for heating and as vehicle fuel including that for trains.

Our tropical climate is favourable for the bacteria in anaerobic decomposition of biomass and for the growth of energy crops or other biomass. Governments should create a natural gas infrastructure and promote biogas on a big way.  Even if they are not interested in helping the common man, it can bring about reduction in imports of petroleum (for fuel and fertiliser) to save the ‘poor’ oil marketing companies from their ‘under recoveries burden’.

 

' there is a huge potential for the installation of medium size biogas plants in the country. The potential can be translated to an aggregated estimated capacity of 8165 MW per day power generation or 22,06,789 LPG cylinders and 21304 lakh kg of urea equivalent or 3974 lakh tones of organic manure/fertilizer per day.

The upgraded biogas can be bottled in CNG cylinders and wherever CNG is currently used, biogas bottling can be used as an alternative.'

 

http://mnre.gov.in/file-manager/UserFiles/casestudy_biogas_bottling_in_India_mlbamboria.pdf

 

Biogas – not just cow power or poo power

 

 

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  • shankar
    shankar -

    Biogas is produced by the anaerobic digestion or fermentation of biodegradable materials such as biomassmanuresewagemunicipal wastegreen wasteplant material, and crops. Biogas comprises primarily methane (CH4) and carbon dioxide(CO2) and may have small amounts of hydrogen sulphide (H2S), moisture andsiloxanes.

    I see biogas being produced in all flat complexes in India in the future, not necessarily in the near future. When LPG runs out, we will wake up.

    The gases methane, hydrogen, and carbon monoxide (CO) can be combusted or oxidized with oxygen. This energy release allows biogas to be used as a fuel. Biogas can be used as a fuel in any country for any heating purpose, such as cooking. It can also be used in anaerobic digesters where it is typically used in a gas engine to convert the energy in the gas into electricity and heat.




    The “Indian Biogas Association” aspires to be a unique blend of; nationwide operators, manufacturers and planners of biogas plants, and representatives from science and research. The association was founded in 2010 and is now ready to start mushrooming. The sole motto of the association is “propagating Biogas in a sustainable way”.

    The Deenabandhu Model is a new biogas-production model popular in India. (Deenabandhu means "friend of the helpless.") The unit usually has a capacity of 2 to 3 cubic metres. It is constructed using bricks or by a ferrocement mixture. In India, the brick model costs slightly more than the ferrocement model; however, India's Ministry of New and Renewable Energy offers some subsidy per model constructed.


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    Family Type Biogas Plants Programme

    National Biogas and Manure Management Programme (NBMMP)

     1.1     Introduction

    Biogas is a clean and efficient fuel. It contains about 65 per cent methane, about 34 percent carbon dioxide and traces of other gases, such as hydrogen sulphide and ammonia.  Biogas is produced when organic materials, such as cattle dung, are digested in the absence of air, in `Biogas Plant'. 

     The Central Sector Scheme on National Biogas and Manure Management Programme, which mainly caters to setting up of family type biogas plants, has been under implementation since 1981-82. National Biogas and Manure Management Programme provides for central subsidy in fixed amounts, turn-key job fee linked with five years’ free maintenance warranty; financial support for repair of old-non functional plants; training of users, masons, entrepreneurs, etc.; publicity and extension; service charges or staff support; State level Biogas Development and Training Centres (BDTC); (fixed amount of CFA to institutional biogas plants); financial support for institutions for cattle dung based power generation plants; etc 

    1.2.      Objectives

    The objectives of programme are as follows:-

    (i)         To provide clean bio- gaseous fuel mainly for cooking purposes and also for other applications for reducing use of LPG and other conventional fuels;

    (ii)        To meet ‘lifeline energy’ needs for cooking as envisaged in ‘Integrated Energy Policy’;

    (iii)       To provide bio-fertilizer/ organic manure to reduce use of chemical fertilizers;

    (iv)       To mitigate drudgery of rural women, reduce pressure on forests and accentuate social benefits;

    (v)        To improve sanitation in villages by linking sanitary toilets with biogas plants;

    (vi)       To mitigate Climate Change by preventing black carbon and methane emissions.

    2.         Potential and Achievement

    A cumulative total of 4.31 million family type biogas plants have been set up in the country against estimated potential of 12 million plants. State-wise information on achievement vis-à-vis potential is given in Annexure-I as per figures of 31-12-2010. 

     3.        Technology

     Approved designs of family type biogas plants   

     i)         Following models of biogas plants are approved for promotion: 

    (a)KVIC Floating Drum Type Biogas Plants having digester made ofbricks or stones.1 to 10 cubic metre
    (b)KVIC Type Biogas Plants with Ferro cement digester   1 to 10 cubic metre
    (c)KVIC Type Biogas Plants with Fibre Glass Reinforced Plastic (FRP) Gas holder1 to 10 cubic metre
    (d)Deenbandhu Model(i)  Brick masonry(ii) In ferrocement with in-situ technique(iii) Prefabricated HDPE material based prefabricated dome for Deenbandhu Model family size Biogas Plants.(iv) Solid – State Deenbandhu design fixed dome biogas plant, developed by ICAR1 to 6 cubic metre
    (e)Pre-fabricated RCC fixed dome model(i)           Shakti-Surbhi FRP based floating dome KVIC portable model biogas plant developed by Vivekanad Kendra, Kanyakumari(ii)         Sintex make plastic based floating dome KVIC type biogas plant, developed by Sintex Industries Ltd., Kalol (Gujarat)2 & 3 cubic metre(0.5 to 2cubic meter biogas plants and higher for higher capacity plants-do-
    (f)'Flxi' model Bag digester type plant made of rubberised nylon fabric manufactured by Swastik Rubber Products Ltd., Pune.1 to 6 cubic metre

    ii)         Size of plants, requirement of cattle dung and estimated cost  

    Size of plantQuantity of cattle dung required dailyNo. of cattle heads requiredEstimated cost*  at 2010-11 prices worked out for Central part of country
    1 cubic metres25 kg2-3Rs.12,080/-
    2 cubic metres50 kg4-6Rs.16,200/-
    3 cubic metres75 kg7-9Rs.19,405/-
    4 cubic metres100 kg10-12Rs.23,350/-

     * The biogas plant cost is higher by 30 per cent and 50 per cent in hilly areas and North Eastern Region States, respectively.

    iii)        Applications

    Cooking            :             Biogas can be used in a Biogas chulhas/ burner for cooking. A biogas plant of 2 cu.m. capacity is sufficient for providing cooking fuel to a family of 4 persons.

    Lighting              :           Biogas can be also used for lighting a biogas lamp in indoor or outdoor. The requirement of gas for powering a 100 candle lamp (60 W) is 0.13 cu.m. per hour.

    Power Generation        Biogas can be used to operate a dual fuel or 100% biogas engine and can replace upto 80% of   diesel in dual fuel engines.

    Refrigeration :               Biogas can also be used for cooling applications in operating the chilling machines.

    4          Implementing agencies  

    The programme is implemented by State Nodal Departments / Agencies and Khadi and Village Industries Commission (KVIC), Mumbai. The list of State Nodal Departments/ Agencies is given at Annexure – II.

     5.1      Central Subsidy :  

    The pattern of Central Financial Assistance under National Biogas and Manure Management Programme

    w.e.f. 1st November 2009 and for remaining period of 11th Plan.

    Sl. No.Items for Central Financial Assistance(CFA)Family type Biogas Plants under CDMFamily type Biogas plants under NBMMP**
      1 cum2-4 cum1 cum2-4 cum
    A.      Central Financial Assistance to beneficiaries of Biogas Plant (in Rs. per plant)
    1.NER States, Sikkim (except plain areas of Assam)11,70011,70014,70014,700
    2.Plain areas of Assam9,0009,0009,00010,000
    3.Jammu & Kashmir, Himachal Pradesh, Uttrakhand, Niligiri of Tamil Nadu, Sadar Kursoong & Kalimkpong Sub-Divisions of Darjeeling, Sunderbans (W.B.) and Andaman & Nicobar Islands3,5004,5004,00010,000
    4.All Others2,1002,7004,0008,000
    B.Turn-Key Job Fee including warranty for five years (in Rs. per plant)7,001,500
    C.Additional CFA for toilet linked Biogas Plants (in Rs. per plant)5,001,000
    D.Incentive for saving Diesel and other conventional fuels by using biogas in engines/ gensets  and/ or biogas based refrigerators (in Rs. per plant)2,5005,000
    E.Administrative Charges- for target range of plants (in Rs.)
    1.100-3,00050,000@1,00,000^
    2.3,001-7,0008,90,000#10,50,000^^
    3.Above 7,00114,90,000$24,50,000 *
    F.    Training Courses (in Rs.)
    1.Users course1,0002,000
    2.Staff Course5,0008,000
    3.Refresher/ Construction-cum maintenance course19,00035,000
    4.Turkey-key operator & management course for workers of companies/ entrepreneurs38,50067,500
    G.Biogas Development & Training CentersAs per existing patternAs per existing pattern
    H.Communication & Publicity –for target range of plants (in Rs.)
    1.Up  to 1,0001,00,0001,00,000
    2.1,001- 10,0002,50,0002,50,000
    3.More than 10,0005,00,0005,00,000
    I.Support for Repair of Non- functional Plants with the restriction of utilization of upto 5 % of the outlay of the programme in that year of the concerned State/ UTNil50% of applicable CFA category subject to sharing of 50% of the cost of repair by the beneficiary.

     

    Family type Biogas Plants under CDM       Family type Biogas plants under NBMMP
    @ Extra Rs.300 per plant in excess of 200 biogas plants.** Maximum of 50% of the cost of the biogas plant for low cost models.      
    # Extra Rs.150 per plant in excess of 3000 biogas plants.^ Extra Rs. 350 per plant in excess of 100 biogas plants.
    $ Extra Rs.100 per plant in excess of 7000 biogas plants & maximum of Rs.30 lakh.^^ Extra Rs.300 per plant in excess of 3000 biogas plants.
     * Extra Rs. 250 per plant in excess of 7,000 biogas plants subject to maximum of Rs. 50.0 lakh.

     

     5.2      State Level Biogas Development and Training Centres    

                State Level Biogas Development and Training Centres are functioning at: (i) Bangalore ( Karanataka),  (ii) TNAU, Coimbatore (Tamilnadu), (iii) CESR, Indore (Madhya Pradesh), (iv) IIT, Kharagpur (West Bengal), (v) Lucknow (Uttar Pradesh), (vi) PAU, Ludhiana (Punjab), (vii) HPKVV, Palampur (Himachal Pradesh), (viii) UPES, Dehradun (Uttaranchal) and (ix) CTAE, Udaipur (Rajasthan) and (x) IIT, Guwahati (xi) IIT, Delhi, (xii) KVIC, Nasik (xiii) KIIT, Bhubaneshwar for providing technical, training and publicity support to State nodal departments and programme implementing agencies.

    5.3       Training courses :  Financial assistance is given for organising different kinds of training courses as mentioned below :- 

    CourseDurationNo. of  trainees per courseCentral financialAssistance per course
    UsersOne day50-60Rs.2,000/-
    Staff2-3 days10-15Rs.8,000/-
    Refresher/ Construction-cum- Maintenance16 days10Rs.35,000/-
    Turn-Key Workers15 days10Rs.67,500/-

     5.4      Communication and publicity  :  Assistance is given for communication and publicity work linked with target ranges to State nodal departments and agencies. 

     6.         Programme during Eleventh Plan

    Promotion of biogas plants continued during the XI Plan.  A target of setting up of 6.47 lakh family type biogas plants has been fixed with a plan outlay of Rs.562.00 crore. Year-wise achievements vis-à-vis targets and budget- expenditure during 2007-08 to 2009-10 and 2010-11 upto 21-02-2011 is as given below: 

      Year(No. of plants)
    Achievement
    2007-0888,840
    2008-091,07,929
    2009-101,19,914
    2010-1171,165
    2011-12 

      7.         Monitoring

    A three-tier monitoring system exists, which consists of self-reporting by State Governments and implementing agencies involving 100 per cent physical verification of biogas plants at the block level. The second level is by random basis verification by State nodal departments and implementing agencies and KVIC at State level. The third-tier involves filed inspection on random basis by Regional Biogas Development and Training Centres of MNRE.

     8.         Evaluation studies

    At the instance of the Ministry, an independent evaluation diagnostic survey study on National Biogas and Manure Management Programme has been conducted by APITCO Ltd. Hyderabad for plants installed during 10th plan. The study covered plants set up during the years 2002-03 to 2006-07 in 6 States, namely, Assam, Gujarat, Kerala, Punjab, Chattisgarh and West Bengal. The report received in August, 2009, indicated that about 95.81% of the plants are in operation/ working.

     9.         New Initiatives

    The Ministry launched another Programme on Biogas based  Distributed/Grid Power Generation in January 2006 (2005-06) so as to set up reliable decentralized power generating units(3KW to 250KW) in rural areas in the country. The per KW Central Financial Assistance (CFA) of Rs. 40,000 (3-20 KW), Rs. 35,000 (>20 to 100 KW) and Rs. 30,000 (>100 to 250 KW) is available for the installation of biogas based power generation units. The programme is implemented through nodal departments/ agencies of the states/ UTs, KVIC, institutions and Biogas Development and Training Centres (BDTCs) of MNRE.

    Recently During the year 2008-09, the Ministry took up a new initiative to demonstrate an Integrated Technology-package in entrepreneurial mode on medium size (200-1000 cum/day) biogas fertilizer plants (BGFP) for generation, purification/enrichment, bottling and piped distribution of biogas. Installation of such plants aims at meeting stationary and motive power, cooling, refrigeration and electricity needs in addition to cooking and heating requirements. Another EOI invited proposals for setting up such plants having capacity of above 1000 m3 also.

    ANNEXURE-I

    National Biogas and Manure Management Programme (NBMMP)
    State-wise estimated potential and cumulative achievements for family type biogas plants upto 31/3/2011

    State/ Union TerritoriesEstimated PotentialCumulative Physical Achievements as on 31-03-2010Physical Target for 2010-11Physical Achievements during 2010-2011Cumulative Physical Achievements as on 31-3-2011
         
    12345 6
    Andhra Pradesh10650004579381800016275474213
    Arunachal Pradesh750029572001753132
    Assam307000815925000673288324
    Bihar733000125888300350126238
    Goa8000389350183911
    Gujarat554000411950100006105418055
    Haryana300000540832000137955462
    Himachal Pradesh1250004571630044546161
    Jammu & Kashmir128000248910001142603
    Karnataka6800004187591600014464433223
    Kerala15000012646335003941130404
    Madhya Pradesh14910002955801600016742312322
    Maharashtra897000780527800021456801983
    Manipur38000212850--2128
    Meghalaya24000666160012757936
    Mizoram500038202001003920
    Nagaland6700415350011715324
    Orissa60500023981870006050245868
    Punjab4110001052891600023700128989
    Rajasthan9150006734810027567623
    Sikkim730073332403587691
    Tamilnadu61500021651615001493218009
    Tripura280002793100892882
    Uttar Pradesh193800042226945004603426872
    West Bengal6950003185101500017000333510
    A&N Islands2200137--137
    Chandigarh140097--97
    Dadra & Nagar Haveli2000169--169
    Delhi12900679-01680
    Pondicherry430057850-578
    Chattisgarh400000320503700383235882
    Jharkhand100000493310009135846
    Uttarakhand8300010508900208212590
    KVIC*--   
    TOTAL :1,23,39,00042,53,6241,50,7901,51,13844,04,762

                     *The total figures of targets and achievements are inclusive of the achievements made by KVIC

                                                                                                                                                                                                                                                                               Annexure – II

                        List of State Nodal Departments / State Nodal Agencies for implementation of 
                              National Biogas and Manure Management Programme (NBMMP)

    S. No.StateAgenciesPh/ Fax/ Email ID
    1.ANDHRA PRADESH Managing DirectorNon-Conventional Energy DevelopmentCorporation of Andhra Pradesh (NEDCAP) Ltd.5-8-207/2 Pisgah Complex NampallyHyderabad – 500001Off 040-23202391/ 23203638/23203376/23202262Fax: 040-23201666Email:info[at]nedcap[dot]gov[dot]in
    2.ARUNACHAL PRADESHDirector,Arunachal Pradesh Energy Development Agency (APEDA)(A State Government Agency)Urja Bhawan TAdar Tang Marg,Post Box No. 141, Itanagar – 791111Off: 0360-2211160
    3.ASSAMState Nodal officer FDA CumChief Conservator of Forest,Social Forestry, Assam,Baristha, Guwahati – 29Ph. & Fax 0361 – 2305099 
    4.BIHAR  DirectorBihar Renewable Energy Development AgencyIst Floor, Sone Bhawan,Virchand Patel Marg,Patna – 800001(KOHIMA) Phone : 0612-2228734 (O)e-mail:director[at]sdabeebreda[dot]comwebsite : www.sdabeebreeda.com 
    5.CHATTISGARH Director,Chattisgarh State RenewableEnergy Development Agency,D2/D3, Shriram Nagar, Near Railway Crossing,Vidhansabha Road,Raipur- 492007 (C.G)Off-0771-4019239/ 4019225Fax: 0771-4268389
    6.GOADy. Director of Agriculture (PP)Directorate of Agriculture,Govt. of Goa, Krishi Bhawan,Tonca- CaranzalemPanaji Goa.Off-0832-2465443Fax: 0832-2422243Email: dir-agri[dot]goa[at]nic[dot]in
    7.GUJARATChief Managing Director,Gujarat Agro Industries Corporation Ltd.,Khet Udyog Bhawan, Oppsite- Old High CourtNavrangpura, Ahmedabad – 380014Ph. 079-27544741 – 42, 27540254, 27543743
    8.HARYANA Joint Director (Agri’l Engg.)Directorate of Agriculture,Krishi Bhawan, Sec. 21,Panchkula (Haryana)Director,Haryana Renewable Energy Development Agency (HAREDA)SCO 48, Sector – 26Chandigarh - 160019Off-0172-2576210Fax-0172-2576210 
    9.Himachal PradeshDirector (Agriculture)Department of AgricultureGovt. of Himachal PradeshShimla – 171005Ph. 0177-2830618/2830174
    10.Jammu & Kashmir Director (IREP),Directorate of  IREP (DAR Building)Bouleward Road Nehru Park, Sri Nagar. Ph. 0191-2432539 – Office winter. Ph. 0194- 2475674 – office summer. Fax 0191-2432539
    11.JHARKHAND The CEO & Director,Jharkhand Renewable Energy Development AgencyPlot No. 328/B, Road No. 4Ashok Nagar, P.O.- DorandhaRanchi – 834002 (Jharkhand)Ph.: 0651-2246970/ 2247049 / 2240692Fax:-0651-2240665 
    12KARNATAKA Principal Secretary to Government of Karnataka,Rural Development & Panchayati Raj Department,Karnataka Government Secretariat,M. S. Building, Bangalore- 560001Ph. 080-22353929Fax-080-22353927 
    KARNATAKA RENEWABLE ENERGY DEVELOPMENT AGENCY LTD. No. 19, Maj. Gen. A D Logandan, INA Cross Queen’s Road, Bangalore – 560 052Ph: 080-22282220, 22282221, Fax: 080-22257399E-mail: kredlnte[at]yahoo[dot]co[dot]in Web: www.kredl.kar.nic.in
    13.KERALASh. B. J. JayakumarAdditional Director of AgricultureDirectorate of AgricultureVikas Bhawan, ThiruvananthapuramKeralaTelefax: 0471-2306219
    Director,Agency for Non-Conventional EnergyAnd Rural Technology (ANERT)C. No. 14/649Opposite Thycad House, Thycaud P.O.Thiruvananathapuram-695014Off- 0471-2338077, 2333124, 2331803
    14.MADHYA PRADESH (1) Managing DirectorMadhya Pradesh State AgroIndstiries Development Corporation Ltd.Panchanan, 3rd Floor,, Malviya NagarBhopal – 462003Ph.: 0755-2556566/2553595Fax: 0755-2557305Email:mpagro_bpl[at]airtelmail[dot]inwww.mpstateagro.nic.in 
    (ii) Managing DirectorM. P Urja Vikas Nigam Ltd., UrjaBhawan, Link Road No. 2, Shivaji   Nagar,Near Bus Stop No. 5     Bhopal – 462016Tel:– 0755-2556526,2556566,2767270 
    (iii) Project CoordinatorSpecial Expert (Energy)M.P. Rural Livelihood ProjectGovt. of M.P, Panchayat & RuralDevelopment Department.3rd Floor, Beej Bhavan,     Arera Hills Bhopal- 462004 (M.P)Ph. 0755-2766816Fax: 0755-2766816 
    15MAHARASHTRA Dy. Secretary to Govt. of Maharashtra,Rural Development and Water Conservation Department,Room No. 163(Main), Ist Floor,Mantralaya, Mumbai – 400032Ph.-022-22844613(O) ,Fax-022-22831017e-mail:irdpcell[at]gmail[dot]com
    16.MANIPURMember Secretary,Manipur Renewable EnergyDevelopment Agency (MANIREDA)Science & Technology ComplexDepartment of Science, TechnologySai Road, Takyelpat, Imphal- 795001 
    17.MEGHALAYADirectorMeghalaya Non-conventional & Rural EnergyDevelopment Agency (MNREDA)Lower Lacheaumiere, Opp. P&T DispensaryNear BSF Camp (Mawpat)Shillong – 793011Ph. 0364-3537343 / 2536138  
    18.MIZORAMJoint Director (Biogas)Joint Director & Nodal officer for BiogasDirectorate of Animal Husbandry and VeterinaryBungkawn Road, KhatlaGovt. of MizoramAizwal- MizoramPh. 0389- 2333660 (DR) / 2334555 Telefax- 0389- 2333660Fax: 0389 - 2333234
    19.NAGALAND DirectorNew and Renewable Energy,Old Industries & Commerce Office BuildingUpper Chandmari, Kohima, NagalandPh. (Off.) : 0370 – 2242565/66
    20.ORISSA Chief Executive,Orissa Renewable Energy Development Agency(under deptt. of Science & Technology) Govt. of Orissa,S-59, Mancheswar Industrial EstateBhubneswar – 751010 (ORISSA)Ph. 0674-2588260(DR)Fax0674-2586368
    21.PONDICHERRY Project DirectorRenewable Energy Agency of PondicherryNo. 10, Second Main RoadElango Nagar, Pondicherry- 605011Off- 0413-2244319Fax- 0413-2244219 
    22.PUNJABDirector,Punjab Energy Development AgencySolar Passive ComplexPlot No.1 & 2, Sector  33-DChandigarh (U.T) – 160034Ph.0172-2667005 / 2663352/ 2615853/ 2646291
    23.RAJASTHAN Deptt. of Renewable Energy SourceCollege of Technology & EngineeringMaharana Pratap University of Agriculture & Technology, Udaipur – 313001Ph. 0294- 2471068(o)0294-2811557 (R)Fax: 0294-2471056
    24.SIKKIM Director,Sikkim Renewable Energy DevelopmentAgency (SREDA), SREDA BhawanD.P.H Road (Near Janta Bhawan)GANGTOK – 737101, SikkimPh: 03592-221127 / 229810Fax:  03592-221127E-mail:sreda[dot]sik[at]nic[dot]in
    25.TAMILNADUDirector,Directorate of Rural Development &Panchayat Raj, Govt. of Tamil Nadu,PANAGAL Building-1, Jenis RoadSaidapet Chennai – 600015Ph. 044-24338690Fax-044-24343205
    26.TRIPURAShri Subhash Chaudhary,Director & Chief Executive Officer,Tripura Renewable Energy Development AgencyVigyan Bhawa, 2nd Floor,Pandit Nehru ComplexWest Tripura, Agartala – 799006Fax-0381-2225900 
    27.UTTRAKHAND DirectorUttranchal Renewable Energy (UREDA)Development Agency, (UREDA) Energy Park CampusIndustrial Area, Patel Nagar,Dehradun – 248001Ph-0135-2521387Fax-0135-2521386 
    Sh. Shailender Singh BistDy. Commissioner (Programme)Rural DevelopmentDirectorate of Rural DevelopmentUttarakhand PauriMob. 09412079684, Ph.- 01368-223896/ 222295Fax- 01368-223895Email-crd_pauri[at]yahoo[dot]com 
    28.UTTAR PRADESH Commissioner,Deptt. of Rural Development,Government of U.P10th Floor Jawahar Bhawan,Ashok road, Luchnow (U.P)Ph. 0522-2286015 / 2286022Fax: 0522-2286023/ 2286025e-mail: crd-up[at]nic[dot]in  
    Shri Nitishwar KuomarDirectorUttar Pradesh New and Renewable Energy Development Agency (NEDA), U.PVibhuti Khand, Gomti NagarLucknow – 226010 (U.P)ho_aks[at]rediffmail[dot]comPh. 0522-2720652Fax: 2720779e-mail:nedaup[at]dataone[dot]in
    29.WEST BENGAL DirectorWest Bengal Renewable EnergyDevelopment AgencyBikalap Shakti Bhawan, Plot- J-1/10,EP & GP Block, Salt LakeElectronics Complex, Sector- VKolkata – 700091Ph. 033-23575038, 23575348 Fax: 033-23575037e-mail:wbreda[at]cal[dot]vsnl[dot]net[dot]in 
    30.KVICDr. S.N ShuklaDirector (Bio Technology)Khadi and Village IndustriesCommission3, Irla Road, Vile Parle (West)Mumbai – 400056Off- 022-26711052/Fax :  022-26713696Email:nce[at]kvic[dot]gov[dot]in   

     





    BIO GAS
     

    1. Energy Crisis

    Energy is a necessary concomitant of human existence. Although many sources of energy exist in nature, it is coal, electricity and fossil oil  which have been commercially exploited for many useful purposes. This century has witnessed the phenomenal growth of various industries based on these energy sources. They have application in agricultural farms and have domestic use in one form or other. Fossil oil, in particular has played the most significant role in the growth of industry and agriculture, which would be recorded in the history of progress of human race in golden words. Whether it is flying in the air or speeding automobiles on the roads or heating and prime moving in the industry or petro-chemicals and fertilizers for farms or synthetics for daily use or cooking at home, all have been made possible by one single source - fossil oil. By now, it has penetrated so deep into the mechanism of human living that man is not prepared to accept the fact that this useful source of energy is not going to last very long. But that is the fact of life. Once fossil oil was available easily and at lower prices irrespective of its origin of supply. It has now been scarce and costly. The immediate effect of this is that the world is in a grip of inflation and rising prices. Today, energy crisis has mainly emerged from the fear that the boons of fossil oil may turn into a bane as the disappearance of fossil oil would compel the habits and practices of living of the society to change. That is the crisis and that is the compulsion for search alternate sources of energy.

    2. Bio-Gas as one of the Alternate Renewable Sources of Energy

    It is evident that no single source of energy would be capable of replacing fossil oil completely which has diverse applications. On the other hand, dependence on fossil oil would have to be reduced at a faster pace so as to stretch its use for longer period and in critical sectors till some appropriate alternative energy sources preferably renewable ones are made available. Presently, the country is spending a fortune in importing fossil  oil which can hardly be afforded for long on the face of developmental needs. Methane gas and more popularly known as bio-gas is one such alternate sources of energy which has been identified as a useful hydro-carbon with combustible qualities as that of other hydrocarbons. Though its calorific value is not high as some products of fossil oil and other energy sources, it can meet some needs of household and farms. Following table would provide an idea of comparative heat values and thermal efficiency of commonly used fuels in the household and farms.

     
    Table-1
     

    Commonly used fuels

    Calorific values in Kilo calories

    Thermal efficiency

    Bio-gas

    4713/M3

    60%

    Dung cake

    2093/Kg

    11%

    Firewood

    4978/Kg

    17.3%

    Diesel (HSD)

    10550/Kg

    66%

    Kerosene

    10850/Kg

    50%

    Petrol

    11100/Kg

    ---

     

    These calorific values or heat values indicate that bio-gas can perform works similar to fossil oil in domestic cooking, lighting etc., with better efficiency depending upon the methane content in it. The bio-gas has also the potential for use in internal combustion engines used for pumping water etc. for which research and development works are in progress. Biogas, therefore, has a bright future as an alternate renewable source of energy for domestic and farm use.

    3. Bio-Gas, its Production Process and Composition

    It would be useful to know what bio-gas is and what its properties are-

    (i) Bio-gas:  Itmainly comprises of hydro-carbon which is combustible like any hydro-carbons and can produce heat and energy when burnt. The chemical formula of the hydro-carbon is CH4 where C stands for carbon and H for hydrogen and chemically the gas is termed as methane gas. The chemical formula of some other commonly used hydrocarbons derived from fossil oil viz. petrol, kerosene, diesel, etc. are C6H14 , C9H20 and C16H34 respectively. Unlike these hydro-carbons which are derived from direct chemical processes, bio-gas is produced through a bio-chemical process in which some bacteria convert the biological wastes into useful bio-gas comprising methane through chemical interaction. Such methane gas is renewable through continuous feeding of biological wastes and which are available in plenty in rural areas in the country. Since the useful gas originates from biological process, it has been termed as bio-gas in which methane gas is the main constituent.

    (ii)  Production Process:The process of bio-gas production is anaerobic in nature and takes place in two stages. The two stages have been termed as acid formation stage and methane formation stage. In the acid formation stage, the bio-degradable complex organic compounds of solids and cellulose presents in the waste materials are acted upon by a group of acid forming bacteria present in the dung and reduce them into organic acids, CO2, H2, NH4 and H2S. Since the organic acids are the main products in this stage, it is known as acid forming stage and this serves as the substrates for the production of methane by methanogenic bacteria.

    In the second stage, groups of methanogenic bacteria act upon the organic acids to produce methane gas and also reduce CO2 in the presence of H2 to form methane (CH4). At the end of the process the amount of oxygen demanding materials in the waste product is reduced to within the safe level for handling by human beings. There are four types of methano-genic bacteria; Methano-bacterium, Methano-spirillium, Methano-coccus and Methano-circina. These bacteria are oxygen sensitive and photo-sensitive and do not perform effectively in the presence of oxygen and light.

    Constituents

    The gas thus produced by the above process in a bio-gas plant does not contain pure methane and has several impurities. A typical composition of such gas obtained from the process is as follows:

     
    Table-2
     
    Methane   

    60.0%

    Carbondioxide

    38.0%

    Nitrogen  

    0.8%

    Hydrogen 

    0.7%

    Carbon-monoxide

    0.2%

    Oxygen 

    0.1%

    Hydrogen Sulphide

    0.2%

     

    The calorific value of methane is 8400 kcal/ m3 and that of the above mixture is about 4713 Kcal/ m3.  However, the bio-gas gives a useful heat of 3000 kcal/m3. If similar heat values are to be obtained from other sources of fuel, the equivalent quantities of those  fuel have to be substantial as may be seen from Annexure-III. It is not the quantity  which is so important but while bio-gas is renewable, others are not.

    4. Scope of Bio-Gas Plants

    The basic feed material for, bio-gas plants in India has been considered to be cattle dung which is available in plenty. The estimated cattle population of 238 million in the country has the potential to produce about 1000 million tonnes of dung every year. According to an estimate (1977) of Khadi and Village Industries Commission (KVlC), bio-gas plants of average family size may provide energy equivalent to 5432 million liters of kerosene which in terms of current prices may cost well over Rs. 1000 crore per annum. Although, cattle dung has been recognized as the chief raw material for bio-gas plants, other materials like night-soil, poultry litter and agricultural wastes are also used where they are socially acceptable. In addition to combustible gas, the bio-gas plants would also be a source for conserving organic manure, rich in NPK. It is estimated that recoverable dung from 236 million cattle can add about 3.5 million tonnes of Nitrogen to the soil every year and for ensuring its conservation bio-gas plants can be very useful. The scope for bio-gas plants in India, therefore, is substantial if the benefits accruable from such plants are exploited by people living in rural areas.

    5. Major Benefits of Installing Bio-Gas Plants

    It is estimated by the Govt. of India, Ministry of Energy, that alternative sources of energy like bio-gas plants, wind mills etc. may reduce the dependence on conventional sources of energy by about 20% by the turn of the century, provided promotional efforts are continued. Presently, the cooking media in rural areas consist of burning dung cake, fire-wood and to some extent kerosene where it is available easily. The installation of bio-gas plants would directly replace the use of above three and in saving them, following gains would be made:

    (i) Nearly 30% of available dung which is burnt and wasted would be recovered as bio-gas plants conserve the dung while producing bio-gas.  Again, the dung after digestion in gas plant preserves more of NPK in the dung solids and cellulose which otherwise gets lost if heaped in the open.

     
    Table-3 
    Percent NPK
     

       

       N

       P2O5   

       K2O

    Bio-gas slurry   

    1.4   

    1.0

    0.8   

    Farm Yard Manure (FYM)   

    0.5 

     0.2

    0.5

    Town Compost   

    1.5   

    1.0

    1.5

     

    The benefits derived from bio-gas plants in terms of manure and  useful energy are illustrated at Annexure 1& II. The average NPK content of Farm Yard Manure (FYM) is about 0.5, 0.2 and 0.5 percent respectively and it may be observed that biogas slurry is rich in NPK by more than four times than ordinary dung when converted into FYM. When the country is faced with shortage of fertilizers and has to spend enormous amounts for its import, the application of bio-gas slurry can replace the chemical fertilizers to a large extent. Bio-gas slurry or FYM not only adds NPK but it proves the soil porosity and texture. These are established benefits.       

    (ii) Second major benefit is that rural people would gradually stop felling trees. Tree felling bas been identified as one of the major causes of soil erosion and worsening flood situation. Government has started massive afforestation programme to tackle the erosion and flood situation. Continued deforestation has been causing ecological imbalances in the environment in which we live. Bio-gas plants would be helpful in correcting this situation.

    (iii) In rural areas kerosene is used for lighting lantern and cooking in a limited way wherever kerosene supply has been made possible. Whatever quantity is used can be replaced by bio-gas as it can be used for lighting and cooking. This would reduce the dependence on fossil oil directly and in saving foreign exchange.

    (iv) Lastly, the most important social benefit would be that the dung being digested in the digester, there would be no open heap of dung to attract flies, insects and infections. The slurry from digesters can be transported to the farm forapplication in the soil, thus keeping the environment clean forinhabitation. Also, gas cooking would remove all the health hazards ofdung cake orfire wood cooking and would keep the woman folk free fromrespiratory and eye diseases  which are prevalent in the villages.

     

    6. History of Technological Development, Past Achievements, Future Programme and Role of Institutional Finance History of Technological Development

    The bio-gas technology is not new to India. Its experimentation started in 1940 when Dr. S.V. Desai after visiting Dadar sewage puri­fication station at Bombay took up an experimental gas plant at Indian Agricultural Research Institute (IARI). The cattle dung fermentation fol­lowed next  which was patented by Shri Jasbhai J Patel in 1951. However, the model had undergone several modifications and in 1954 the plant was named Gramlaxmi III. The same model has been propagated by KVIC in a nation wide programme since 1962. This KVIC model has stood the test of time although many institutions and indi­viduals kept experimenting for better models and introduced several mod­els but not good enough to completely replace the KVIC model. How­ever, the late seventies saw the new Janata model where the difference in cost was about 20%. Even this model has not affected the popularity of KVIC model. It's designs etc. has been discussed later in this paper.

    Past Achievements and Future Programmes

    All along since 1962, KVIC was the sole agency forpromotion of bio-gas plants independent of government programme. The threat of oil embargo during the last Arab-Israel war in 1973 made the Government to include Bio-gas plants as alternative sources of energy to reduce the. dependence on fossil oil on its Vth Five Year Plan. The target set was one lakh gas plants for the plan period. However only 80,000 gas plants were reported to have been installed inspite ofthe fact that government provided 25-50% subsidy to the users.  It was more vigorously pursued in the VI Five Year Plan with a target of 4 lakh gas plants. It is estimated that at the end ofVIPlan the achievement is no more than 45% of its target. The programme ofbio-gas plants are now covered under the National Biogas and Manure Management Programme (NBMMP) of Govt. of India, Ministry of Non Conventional Energy Sources. The NBMMP will be implemented with a physical target of 1.60 lakh biogas plants during FY 2003-2004.

    It can be noted from the above discussion that during last 21 years, the achievement has not, been appreciable. The government is now convinced that bio-gas plant technology is not a failure. However, social environment has to be more favorable for the speedier progress. For example, China has taken a rapid stride in the same field where the social environment is favorable to bio-gas technology.

    The Relevance of Chinese Experience

    A comparative study of India and China carried out by Centre for Application of Science & Technology to Rural Areas (ASTRA), Indi­an Institute of Science, Bangalore gives a striking revelation of the achievement of China in the field of bio-gas. India started the experi­mentation much earlier and actual programme started in 1967 where as China took to this technology only in 1970. Even after a late start, China over took India to reach anunbelievable target within a short span of 7 years. However, with persistent efforts thereafter, the Indian programme got some fillip but there is still a long way to go to tap the potential. This can be observed from the following:

    Table-4

    Year    Population of Bio-Gas Plants India

     
       India  China

    1973   

       8,000

       5,000   

    1980   

       80,000   

      72,00,000  

    1998   

       27,50,000   

       69,00,000

     

    The achievement of China deserves all appreciation as they have managed to install so many numbers without much of cattle dung but with sources  which are within easy reach. The daily feed in Chinese gas plants consists of 20 kgs. waste from four pigs, 4 kgs. waste from 5 hu­mans, 6 kgs. of straw and poultry litters. All these are available with majority of Chinese families and so they have been successful in popularizing the gas plant, as feed was not a constraint. In India, rural population would perhaps not adopt such raw materials as their Chinese counterparts do. In  our country. rural people are ready to handle cattle dung but not other raw materials and number of such families owning 4-5 cattle are not many. Only 20% of the household own 4-5 cattle. Unless the remaining rural families adopt raw materials like Chinese have done, very limited success can be hoped. Chinese have followed the programme with all seriousness inspite of the fact that they are self-sufficient and exporter of fossil oil. When Chinese could take advance measures to counter the future energy crisis, we should be more vigilant in taking this programme seriously.

    However, a word of caution is added here that since large number of plants are failing in the field, sufficient care should be taken to select the type of plant and for sound construction.

    Role of Institutional Finance

    The responsibility for providing technical guidance, installa­tion, supervision and also subsidy has been entrusted to KVIC and the states by the Government who have acquired sufficient experience due to their long association with the bio-gas programme. However, it has been observed that most of the plant users fail to raise their own contribution due to lack of resources. This made the financial institutions difficult to play its role in meeting the credit requirement. During the year 1974-75 the commercial banks entered the fray.  The Govern­ment has now attached top priority to the bio-gas programme in which banks have a special role to play in making the programme successful. It is in this context that bank officials would have to acquaint themselves with the technology, operations, field problems, post installation maintenance and economical and social aspects of bio-gas plants and its programme so that formulation, appraising and processing of schemes become easier.

    7. Main Features of the Bio-Gas Plant

    On the basis of the gas holder the present bio-gas plants are classified mainly into two groups -fixed dome type or floating drum type. Both the type of plants have the following functional components:  

    (i) Digester : This is the fermentation tank and is built partially or fully underground. It is generally cylindrical in shape and made up of bricks and cement mortars. It holds the slurry within it for the period of digestion for which it is designed.

    (ii) Gas holder: This component is meant for holding the gas after it leaves the digester. It may be a floating drum or a fixed dome on the basis of which the plants are broadly classified. The gas connection is taken from the top of this holder to the gas burners or for any other purposes by suitable pipelines. The floating gas holder is made up of mild steel sheets and angle iron and is required to exert pressure of 10 cms of water in the gas dome masonry and exert a pressure upto 1m of water column on the gas.

    (iii) Slurry mixing tank: This is a tank in which the dung is mixed with water and fed to the digester through an inlet pipe.

    (iv)  Outlet tank and slurry pit: An outlet tank is usually provided in a fixed dome type of plant from where slurry in directly taken to the field or to a slurry pit. In case of a floating drum plant, the slurry is taken to a pit where it can be dried or taken to the field for direct applications.

    8. Broad Basis of Plant Design

    For designing a bio-gas plant, there is a need to match the gas requirement to the feed material available so that there is a continuity of gas production and supply without interruption. For this; it is useful to know the average requirement of gas for different uses, dung produced per day and average gas production per units of different feed materials. Some basic information on these aspects are furnished in annexure I to VI.

    The design of a plant may be determined in the following manner:­

    (a) Bio-Gas requirement: Make use of Annexure IV to decide the total requirement of gas per day. If we take a case where gas requirement is 3 cum, further consideration of the design may be followed as observed in the following paragraphs:­

    (b)Raw Material Requirement : To find out the quantity of equiva­lent dung for production of 3 cum gas refer Annexure - V. By dividing 3 cum by 0.04 cum. which is equivalent to 1 kg of dung it would reveal the  total quantity of dung required for the purpose.  In this case it is  3/0.04= 75 kgs. Thereafter, refer Annexure VI to know the number at animals necessary to produce 75 kgs. of dung.

    (c) Digester Design : When dung is mixed with an equal quantity of water, it gives a slurry which has a specific gravity of 1.089. So the volume of slurry fed per day would be equal to (75 + 75)/ (1000 x 1.089) = 0.138m3

    Therefore, for a 50 days retention plant, the volume of the digester has to be equivalent to 0.138 x 50 or 6.9 m3  say 7 m3.

     The recommendation of KVIC is to have a digester volume of 2.75 times the volume of gas produced per day. The commissions recommendation for the depth of the plant is between 4 to 6 m according to the size but for economical use of building materials, a depth to diameter ratio between 1.0 to 1.3 are considered ideal for all types of plants. In a floating drum plant, a continuous ledge is built into the digester at a depth 10 cm. shorter than the height of the gas drum to prevent the gas holder from going down when no gas is left in it. It helps in preventing the gas inlet being choked. It also guides the gas bubbles rising from the side of  the plants into the gas bolder. In some plants slurry is fed at the bottom and removed at the top. When the digester diameter exceeds 1.6 m, a parti­tion wall is provided in the digester to prevent short circuiting of slurry flow and increasing its retention period. Some standard dimensions of such floating drum plants are given at Annexure VII. In case of fixed dome plants, the volume of digester comes to between 1.5 times to 2.75 times the gas produced per day. Here, the higher the plant capacity, the lesser becomes the ratio of digester volume to gas produced per day.

    (d) Gas Holder Design: The design of a gas holder is influenced by the digester dia­meter and distribution of gas use during the day. For domestic plants, the gas holder capacity is kept at 60 per cent of a day's gas production and in case of laboratories, it is kept at 70 per cent of the day's gas production.  In a floating drum plant, the gas holder diameter is 15 cm. less than the diameter of the digester and accordingly the other dimensions are decided. The gas holder can be given a rotary movement around its guide to break the scum formation at the top. In a fixed dome plant the dome angle is kept between 17° and 21° and it gives a pressure upto 100 cm. of water. Due to higher pressure, the diameter of gas pipelines can be re­duced and the gas can be taken to greater distance. In this plant, care should be taken to provide and an earth pressure equivalent to 100 cm of  water column from the top of the dome. Always use 'A' class bricks in the domes for better stability.

    (e) Inlet Tank : Before the dung is fed into the plant, it is mixed with water in a tank to give a solid content of 7.5 per cent to 10 per cent in the slurry. This tank also helps in removing grass and other floating materials from the raw materials to prevent excessive scum formation in the plant. This tank is connected to the digester by an asbestos cement pipe. The floor of the mixing tank is given a slope opposite to the direction of inlet pipe to help heavy inorganic solid particles to settle and get separated from the slurry.

    9. Base Pre-requisites of Bio-Gas System

    (i) Land and Site: While selecting a site for a bio-gas plant, following aspects should be considered:

    (a) The land should be leveled and at a higher elevation than the surroundings to avoid runoff  water.

     (b) Soil should not be too loose and should have a bearing strength of 2 kg/cm2

    (c) It should be nearer to the intended place of gas use.

    (d) It should also be nearer to the  cattle shed/ stable for easy handling of raw materials.

    (e) The water table should not be veryhigh.

    (f) Adequate supply of water should be there at the plant site.

    (g) The plant should get clear sunshine during most part of the day.

    (h) The plant site should be well ventilated as methane mixed with oxygen is very explosive.

    (i) A minimum distance of 1.5m should be kept between the plant and any wall or foundation.   

    (j) It should be away from any tree to make it free from failure due to root interference.

    (k) It should be at least 15m away from any well used for drinking water purpose.

    (l) There should be adequate space for construction of slurry pits.

    (ii) Feed for gas plants: The feed for gas plants in India mainly comprises of dung from cattle. Although, quantity of dung per cattle depends upon health, age, type and many other factors, it is generally believed that, average cattle yield is about 10 kg dung per day. On this presumption, the number of cattle required for various sizes of gas plants as has been recommended by KVIC can be taken from following table.

    Table-5 Requirement of cattle for various sizes of gas plants
     
    Plant Size in M3Minimum number of cattle required

    2   

     3

    3   

     4

    4   

     6

    6   

    10

    8   

    15

    25   

    45

     

    However, it is advisable that assessment of dung and animal requirement may be made as per approach discussed in Sl. 8.

    (iii) Temperature: Temperature plays the most important role in the bio-gas production. The total amount of gas production from a fixed weight of organic waste is best when the temperature is within the messophillic range 25°C-37°C and thermophillic range between 45°C-55°C. The gas yield is maximum in the thermophillic region and the period of digestion is also reduced. It takes about 55 days in messophillic range for digestion where as it takes about 7 days in thermophillic region.


    (iv) Hydrogen ion Concentration: pH of slurry in the digester should be maintained between 6.8 and 7.2 for optimum gas production and this can be accomplished by maintaining proper feeding rate. pH indicates the acidity and alkalinity of the feed mixture. Any excessiveness of acidity or alkalinity would affect gas production. There are a number of ways to correct the pH if the slurry becomes acidic or alkaline.

    (v) Agitation: Mechanical agitation of the scum layer and slight stirring of slurry improves gas production but violent stirring retards it.

    (vi) Solid Content: The solid content in the slurry should be maintained between 7.5 to 10 per cent for optimum gas production.

    (vii) Carbon to Nitrogen Ratio: A carbon to nitrogen ratio of 20: 1 to 30: 1 is found to be optimum for bio-gas production. Carbon to nitrogen ratio of various materials is given in Table - 6 as a guide so that the C: N. ratio of bio-gas feed mixture is kept at desired level.

    Table 6 
    Carbon to Nitrogen Ratio of various materials 

    Sr. No.

    Material

    Nitrogen Content (%)

    Ratio of Carbon to Nitrogen

    1.

    Urine

    15.18

    8:1

    2.

    Cow dung

    1.7

    25:1

    3.

    Poultry manure

    6.3

    N.A.*

    4.

    Night soil

    5.5-6.5

    8:1

    5.

    Grass

    4.0

    12:1

    6.

    Sheep waste

    3.75

    N.A. *

    7.

    Mustard straw

    1.5

    20:1

    8.

    Potato tops

    1.5

    25:1

    9.

    Wheat straw

    0.3

    128:1

    *  N.A.:- Data Not Available

    10. Bio-gas Application and Appliances

    Cooking and Lighting: The main use of tbe bio-gas in rural areas is cooking. Firewood, crop residues or dung cakes are not available on regular basis and so are other  conventional sources of energy like kerosene, electricity or coal etc. The other 'use is gas lamp which glows like any bright lamp. Generally, 15 running meter length (RML) of  pipes/tubing are allowed in bio-gas plant schemes along with burners and lamps for schemes financed by banks.

    (i) Dual Fuel Engines: This is a recent appliance where certain modification of  air intake system helps carburation of bio-gas to run the diesel engines. It is well known that diesel engine has wide application in rural areas from irrigation to any stationary operations and these engines can be converted to dual fuel ones. This dual fuel engine is in a position to make use of about 70% bio-gas and 30% diesel. The economy of running dual fuel engine by bio-gas is undisputable but it has certain operational difficulties. 


    The main problem is that while bio-gas plants are located near the house, the running of the diesel pumpsets are required in the fields. 


    As such it is impractical and technically unsound to provide long gas pipes to connect the gas plant with the diesel engines in the field. Another aspect that prohibits the use of bio-gas in diesel engine is that it requires larger gas plants at least 8-10 cum, so as to enable a 1ow 3 HP diesel engine to run for 4-5 hours a day. And often the users prefer the sizes of 2-4 cum gas plants as number of cattles are not many. However, considering large bio-gas plants hold the key to economical operation of dual fuel engines, in future one may see its wide spread application when many such gas plants come into existence.

    (ii) Refrigerations, Incubators and Water Boilers : There are other applications of bio-gas such as refrigerators, incubators and water boiler, Experimentation in this regard has been going on in some R & D centres whose results are awaited before they become common application items. Average requirement of bio-gas for these applications has been. shown in Annexure IV for giving an idea of the quantity of gas consumed by these appliances. 

    (iii) Research and Development in Application of Bio-Gas: Unless ways and means are found for diverse application of bio-gas, it may not receive the appreciation in deserves. Community bio gas plants have been mooted to provide cooking gas, street light and drinking water through pumping. Government of India had proposed during 1983-84 to install 500 community gas plants on pilot basis and study their feasibility for running on cooperative basis. The results may be helpful in spreading similar plants to other areas. 


    Besides, many institutions/individuals in the country have attempted to provide alternative gas plant designs and some 30 designs have been tried so far. Yet the KVIC design and Janata Model are the two which are not only but are recognized by the financing institutions as standard designs and this status would be maintained unless better designs come as replacements. In certain parts of the country use of night soil and connecting latrine to bio-gas plants have already found its social acceptability. However, in most part of the country it is still not socially accepted and when it finds its social acceptability, it would ensure a regular supply of feed besides improving sanitation in rural areas.

    11. Implementation of Schemes

    It was stated earlier that  the bio-gas schemes have been recognized as priority schemes under the new 20 point programme of the government. In order to expedite formulation of schemes and their imple­mentation, government has strengthened the state and district nodal agencies with adequate staff.. Besides this agency Khadi and Village Industries Commission (KVIC) is also helping the banks in formulating the schemes and also in installation and operation of gas plants upto the running stage. They are technically equipped to undertake the field work. They are also responsible for releasing the subsidy to the extent of 25-75% of the total amount depending upon the type of beneficiaries. Scheduled castes and tribes are entitled for higher subsidy. These  subsidies are declared by the government from time to time. Central government also provides subsidy for repairing defective plants. 


    The banks process the individual cases and provide the loan amount directly to the material supplier or contractor. There are approved contractors who supply the main components and material under orders from implementing agency and loaning bank. The procedure has been systematized under the National Bio-gas and Manure Management Programme (NBMMP).

    The unit costs of bio-gas plants vary from district to district because of  local taxes and transport costs and also for variation in site conditions which include soil, sub-surface water etc. KVIC does announce the unit costs of bio-gas plants of various sizes of their model from time to time for major regions which can be taken as the bench mark of unit costs but the actual unit costs may sometimes differ from KVIC rates and in such cases sponsorers of the schemes should provide detailed estimates of costs of material and labour. For simplifying the scrutiny of unit costs, National Bank has prepared a proforma as shown in Annexure VIII for completion by the sponsoring agencies through the help of local KVIC representatives and other local bodies associated with the implementation of schemes. However, in view of the size of the programme, National Bank now fixes unit costs for all plant models taking into account the approved schedule of rates.

    Besides, National Bank has also circulated a check list   which all the banks should complete in order to make sure that all the requisite, information has been furnished in the scheme and. that National Bank clears the scheme without seeking any further clarification. Recently, bio-gas plants have been covered under banking schemes to give a further boost to the programme.

    12. Field Problem in Implementation and Operation

    As has been observed so far that inspite of bio-gas plants having good potential to serve as one of the alternative sources of energy in the midst of energy crisis, the progress made in installing some 1,65,000, bio-gas plants during 1ast 21 years is not appreciable enough when we see China's progress of installing 12,00,000 plants within 7 years period. This strengthens the view that bio-gas has a better chance of success in our country than many other countries in the world where all the basic pre­ requisites are present. 


    Especially, when a fossil oil sufficient country like China can feel the urgency, we should feel greater need for it. Unfortu­nately, we are not realizing the consequences of delaying the adoption of bio-gas plants at present. The government's determination to give fillip to the development of renewable energy sources throws a challenge to all concerned agencies who have to ensure that field problems are overcome and biogas projects are effec­tively implemented. The field problems and operational difficulties have been mostly identified and are known toimplementing agencies and banks should take special note of it.

    With the adoption of solar and wind energy, biogas too will catch up in most parts of india.



    ARTI Biogas Plant: A compact digester for producing biogas from food wasteE-mailPrintPDF

     

     ARTI has developed a compact biogas plant which uses waste food rather than dung/manure as feedstock, to supply biogas for cooking. The plant is sufficiently compact to be used by urban households, and about 2000 are currently in use – both in urban and rural households in Maharashtra. A few have been installed in other parts of India and even elsewhere in the world. The design and development of this simple, yet powerful technology for the people, has won ARTI the Ashden Award for Sustainable Energy 2006 in the Food Security category. This makes ARTI the only organization in the world to win the prestigious Ashden Award twice. ARTI won its first Ashden Award in 2002 for its chain of technologies for converting agricultural waste into charcoal, and using this as a clean domestic fuel.


    This will be ideal for urban flat complexes. Besides food wastes like waste grain flour, spoilt grain, overripe or misshapen fruit, nonedible seeds, fruits and rhizomes, green leaves, kitchen watse, leftover food, can be efficient. Ideal for indian city conditions.

    The impending scarcity of petroleum threatens the world’s fuel supply. Mankind can face this threat successfully with the help of biogenous methane, but the world is yet to take full advantage of this technology, because its practitioners have so far ignore the basic tenet of science – viz. output of work is dependant on the energy available for doing that work. This fact is seen in the current practice of using low calorie inputs like cattle dung, distillery effluent, municipal solid waste or sewerage, in biogas plants, which makes methane generation highly inefficient. To rectify this skewed approach, in around 2003, Dr. Anand Karve (President of ARTI) developed a compact biogas system that uses starchy or sugary feedstock (waste grain flour, spoilt grain, overripe or misshapen fruit, nonedible seeds, fruits and rhizomes, green leaves, kitchen watse, leftover food, etc). Just 2 kg of such feedstock produces about 500 g of methane, and the reaction is completed with 24 hours. The conventional biogas systems, using cattle dung, sewerage, etc. use about 40 kg feedstock to produce the same quantity of methane, and require about 40 days to complete the reaction. Thus, from the point of view of conversion of feedstock into methane, the system developed by Dr. Anand Karve is 20 times as efficient as the conventional system, and from the point of view of reaction time, it is 40 times as efficient. Thus, overall, the new system is 800 times as efficient as the conventional biogas system.


    Potential of Bio-Gas Plants in the Country and in Village from Cow Dung

    1.         Energy potential in the country

    1.1.      22 x 106 animals in the country  x 3.18 kg dry dung/day x collection efficiency

                                                                 = 5.38 x 108kg dry dung/day

    1.2.      5.39 x 108 kg dry dung/day x 365 days/yr.

                                                                = 1.967 x 1011 kg dry dung/yr.

                                                                = 196 x 106 tonnes dry dung/yr.

    1.3.      5.39 x 108 kg dry dung/day x 0.19m3 gas/kg dung

                                                                = 1.02 x 108 m8 gas/day

    1.4.      1.02 x 108m3gas/day x 4.698 K Wh/m3 kWh/day

                                                                4.791 x 108 kWh/day

    1.5.      4.791 x 108 kWh/day x 365 day/yr.

                                                                =175 million MWh/yr.

    1.6. 1.02 x 108m3gas/day x 365 days/yr. x  62.00 x 102 kerosene per m3 gas.

                                                                =23.08 billion litre kerosene

     

    2.         Manure Potential in the Country per year

    2.1.      196 x 106 tonnes dry dung/yr. x 1.2 tonnes manure/tonne dry dung

                                                                 = 235 x 106 tonnes manure/yr.

    2.2.      236 x 106 tonnes manure/yr x 0.016 tonne N/tonne manure

                                                                 = 3.76 x 106 tonnes N/yr

    2.3.      3.76 x 106 tonnes N/yr : 2.1 tonnee N/tonne naphtha

                                                                 =1.76 x 106 tonnes naptha /yr.

    3.     Energy Potential in a Village.    

            Considering overall collection of 100 kg. of dry dung per day in a

            village of 500 persons.                                                                

            3.1100 kg. dry dung/day x 0.19m3 gas/kg dry dung x 4.698 kWh /m3

                                                                = 89.26kWh /day

     

    4.         Manure Potential in the Village

    4.1       109 kg. dry dung/day x 1.2 kg. N/kg manure/kg dry dung

                                                               = 120 kg. manure/day

    4.2 120 kg. manure/day x 0.016 kg N/kg manure.

                                                                =1.92 Kg. N/ day

                                                                =700 kg. N/yr.

    4.3 700 kg N/yr. x 5 kg. food grains/kgN

                                                                = 3.5 tonnes food grains/yr.

     
     
    ANNEXURE – III 

    Equivalent Quantity of Fuel for 1 m3 of Bio-Gas

    Name of the fuel

    Kero-sene

    Fire-wood

    Cow-dung cakes

    Char-coal

    Soft coke

    Butane

    Furn-anceOil

    Coal gas

    Electricity

    Equivalent quantities to  1 m3 of Bio-gas

    0.620

    3.474 kg

    12.296 kg

    1.458 kg

    1.605 kg

    0.433 kg

    0.4171

    1.177 m3

    4.698 kWh

     
     

    ANNEXURE -IV

    Bio-Gas Requirements

    SL. No.          Use        Quantity requirement

    1.   

     Cooking   

    336 - 430 1/ day / person

    2.   

     Gas Stove   

    330 1/ hr /5 cm burner

       

       

    470 1/hr/10 cm burner   

       

       

    640 1/hr/15 cm burner

    3.   

     Burner Gas Lamp   

     126 1/lamp of lighting equivalent to 100 watt filament lamp.

       

       

    70 1/hr/1 mantle lamp

       

       

    140 1/hr/2 mantle lamp

       

       

    1691/lir/3 mantle lamp

    4.   

     Dual fuel engine   

       425 1/hp/hr

    5.   

     Refrigerator   

       100 1/100 litres capacity

    6.   

     Incubator   

       80 1/100 litres capacity

    7.   

     Water boiler   

    110 1/1 litre of water.   

     

    ANNEXURE - V

    Average Maximum Bio-gas Production From Different Feed Stocks

    Sl. No.

    Feed Stock

    Litre /kg of dry matter

    % Methane content

    1.

    Dung.

     350*

    60

    2.

    Night-soil

    400

    65

    3.

    Poultry manure

    440

    65

    4.

    Dry leaf

    450

    44

    5.

    Sugar cane Trash

    750

    45

    6.

    Maize straw

    800

    46

    7.

    Straw Powder

    930

    46

    * Average gas production from dung may be taken as 40 lit/kg. of fresh dung when no temperature control is provided in the plant. One Cu. m gas is equivalent to 1000 litres.

    ANNEXURE-VI

    Average Dung Night-Soil Production

    Sr. No.

    Living Beings

    Quantity of Dung / Night Soil produced (kg/day)

    1.

    Cow, Heifer

    10.0

    2.

    Bullock

    14.0

    3.

    Buffalo

    15.0

    4.

    Young bovine

    5.0

    5.

    Horse

    14.0

    6.

    Horse, young

    6.0

    7.

    Pigs, over 8 score

    2.5

    8.

    Pigs, under 8 score

    1.0

    9.

    Ewes, rams and goats

    1.0

    10.

    Gees and Turkeys

    0.2

    11.

    Lambs

    0.5

    12.

    Duck

    0.1

    13.

    10 hens

    0.4

    14.

    Human beings

    0.4

    Note : For free grazing animals the availability of dung may be taken as 50 per cent of the amount given in the table.

     
     

    All dimensions are in mm

    Plant Size

    D

     

    D2

    L1

    B1

    F1

    h1

    h2

    h3

    h4

    h5

    h6

    h7

    R

    GATE

    2

    2750

    2500

    2370

    850

    610

    580

    680

    765

    810

    680

    1575

    1345

    520

    1610

    610x610

    3

    3100

    2950

    2720

    1216

    900

    746

    846

    828

    880

    845

    1710

    1575

    590

    1865

    610x610

    4

    3610

    3400

    3000

    1372

    950

    825

    1005

    990

    854

    1005

    1845

    1715

    640

    2080

    610x760

    6

    4110

    3890

    3420

    1620

    1380

    660

    840

    1290

    1025

    840

    2315

    1950

    735

    2360

    610x1000

     
     

    ANNEXURE - VII B

    Dimensions of  Floating Drum Type Bio-Gas Plants
    All dimensions in centimeters
     

    Dime-nsio-ns

    Plant capacity , m 3

     

    For 30 Days Retention Period

    For 40 Days Retention Period

    For 55 Days Retention Period

     

    1

    2

    3

    4

    6

    8

    10

    1

    2

    3

    4

    6

    8

    10

    1

    2

    3

    4

    6

    8

    10

    A

    120

    135

    160

    181

    220

    240

    275

    120

    135

    160

    180

    220

    240

    275

    120

    135

    160

    180

    220

    240

    275

    B

    157

    187

    202

    212

    212

    242

    232

    177

    257

    277

    292

    292

    332

    317

    227

    327

    377

    427

    427

    477

    477

    C

    170

    95

    110

    135

    135

    125

    115

    170

    165

    185

    200

    200

    200

    200

    170

    220

    270

    320

    320

    345

    345

    D

    112

    70

    70

    70

    70

    70

    70

    112

    110

    100

    90

    90

    90

    120

    112

    175

    180

    180

    210

    210

    205

    ANNEXURE - VIII

     

    Cost Estimate for Bio-Gas Plants

    Model :                                                                                                            Capacity :

     

    Sr. No.

    Item

    Quantity

    Rate/Unit Quantity

    Cost

    1.

    Earth Work

     

     

     

    2.

    Bricks

     

     

     

    3.

    Cement

     

     

     

    4.

    Sand

     

     

     

    5.

    Morrum/ Stones

     

     

     

    6.

    Skilled labour days for construction of plant

     

     

     

    7.

    Unskilled labour days for plant construction

     

     

     

    8.

    A.C. Pipes (when required)

     

     

     

    9.

    Gas holder

     

     

     

    10.

    Pipes & fittings with. sizes

     

     

     

    11.

    Gas burner/chullah

     

     

     

    12.

    Gas lamp (when required)

     

     

     

    13.

    Any other item, if  required with specific details

     

     

     

    14.

    Transportation charges

     

     

     

     

    *  The rates should be as per the State Government schedule of  rates or approved district schedule  of  rates.


    ANNEXURE -IX 
    CHECK LIST

    Schemes for installation of Bio-Gas Plants

    (To be completed by the Senior 'Executive/Officer forwarding the Scheme)

    NOTE  : Ticks in boxes to signify that the details of relevant information, as per    guidelines circulated by  NABARD, are furnished in the scheme on the following aspects:

     

    1.

    Objectives

    2.

    Whether the scheme area has been specified?

    3.

    Whether the financing bank and its branches have been, specified?

    4.

    Whether the scheme  has been approved by the competent authority?

    5.

    In case of schemes through the State Land Development Bank, whether the State Government's clearance has been obtained?     

    6.

    Background information and the status of the , implementation of such schemes in the area, percentage failure of plants installed in the past in the area and the reasons for failure - Results of evaluation of the programme, if any, done.    

    7.

    Criteria for selection of the beneficiaries and the size of the plant having regard to adequacy of land for plant and connected pits, distance from the point of use of manure, nearness to cattle sheds, number of cattle. owned, availability of water for use of plant, etc.

    8.

    Designs, specifications and quality of material for different sizes of gas plants

    9.

    Designs, specifications and quality of material for different sizes of gas plants

    10.

    Financial returns: Estimated benefits for different sizes of plants, financial rates of returns and repaying capacity.

    11.

    Lending terms : rate of  interest, loan maturities (inclusive of grace period), down payment, nature of security, source and extent of subsidy, if any, available.

    12.

    Arrangements for fabrication of  the gas holder, frame and burners and quality control measures.

    13.

    Arrangements for procurement of the equipment and supply to the beneficiaries.

    14.

    Agency providing the technical support: Whether certificate from the competent agency has been obtained regarding the technical feasibility of  the programme?

    15.

    Availability of staff for technical appraisal of each proposal and furnishing technical certificate on completion and installation of the plant.

    16.

    Arrangements for supervision and monitoring of scheme implementation.

    17.

    Government support : (a) Technical guidance (b) Whether necessary budget provision has been made / proposed if any, required ?

     
    ANNEXURE - X 

    Do's and Dont's for floating Drum Plant
     

     

    DO's

     

    DON’T's

    1.

    Select the size of Bio-Gas plant, depending on the number of animals you have.

    1.

    Do not install a bigger size Bio-gas plant if you don't have sufficient dung for it.

    2.

    Install the Bio-Gas plant at a well as the animal shed. Under normal conditions, the distance between the gobar gas plant and the kitchen may be kept at 9.1 mtrs. (30 ft.) in the case of a 2 cum. (70 cft.) plant, 13.7 m. (45 ft.) for a 3 cum. (105 cft.) plant, 18.2 m (60 ft), for a 4 cum. (140 cft.) plant, 22.8 m (75 ft.) for a 8 cum. (28.0 cft) plant, and so on.

    2.

    Do not install the Gobar gas plant at a distance more than that recommended.  Otherwise you will have to provide additional pipe-line which will add to your cost.

     

    3.

    Make sure that the Gobar Gas plant is installed in an open place, and gets plenty of sunlight during the day time round the year.

    3.

    Do not install the gobar gas plant under a tree, inside the house or in any other shady place.

    4.

    After construction, the digester should be "cured" for 10 to 12 days.

    4.

    Do not use the digester immediately after construction, without proper curing otherwise cracks will develop.

    5.

    The outer side of the digester wall must be compacted with soil.

    5.

    The soil around the outer wall of the digester should not be loosely compacted; otherwise  the digester may get damaged due to slurry pressure.

    6.

    Feed the Gobar Gas Plant with cattle dung and water mixed in the right proportion : add 4 parts of dung to 5 parts of water, to make it a homogeneous mixture.

    6.

    Do not add more than the required  quantity of either gobar or water  - doing so might affect the efficient  production of gas.

    7.

    When filling bio-gas plants with partition wall make sure that it is filled equally on both sides of the central partition wall, side by side up to the guide frame.

    7.

    Do not fill the slurry unequally on both sides – it may cause the central wall to collapse.

    8.

    Make sure that the mixture of gobar gas and water is free from soil or sand.

    8.

    Do not allow any soil or sand particles to enter into the digester; otherwise, they will choke the inlet pipe at the bottom.

    9.

    When the digester is full with the homogeneous gobar water mixture, place the gas holder on the central pipe of the guide frame. Keep the heavy duty gate valve closed.

    9.

    Do not keep the gate valve loose; otherwise gas will escape from the plant unutilized.

    10.

    Rotate the gas holder once or twice every day in order to break the scum.

    10.

    Do not allow scum to form in the digester, otherwise the production of gas will stop.

    11.

    Release the first full drum of gas to atmosphere to avoid any explosion. Bio-gas and oxygen mixture is explosive.

    11.

    Don't  use the gas initially produced as it may cause explosion due to the presence of oxygen.

    12.

    As soon as gas starts accumulating in the gas holder, fit the pipeline from the gas holder to the kitchen. The gas produced should be utilized regularly.

    12.

    The gas should not be burnt directly i.e., from the gas outlet even for testing purpose.

    13.

    For efficient cooking, keep the approved burner preferably in the kitchen.

    13.

    Do not light the burner in the open otherwise there can be considerable loss of heat.

    14.

    Open the gas regulator cock at the time of its actual use.

    14.

    Do not leave the gas regulator open when the burner is not in use.

    15.

    Adjust the flame by turning the air regulator till a blue flame is obtained. This will give maximum heat.

    15.

    Do not use the gas if the flame is yellow.  Adjust the flame till it is blue in colour.

    16.

    At an interval of 4-5 days drain out any condensed water which may have accumulated in the gas supply pipe.

    16.

    Do not let any water accumulate in the  gas pipe otherwise the required pressure of gas will not be maintained and the flame will sputter.

    17.

    Periodically clean the gas holder from the outside with fresh water to avoid any crust formation.

    17.

    Do not keep the gas  holder dirty.

    18.

    Store the slurry in a proper pit so that the liquid content may not leak through.

    18.

    Do not make slurry pit more than 0.9 mtr. (3 ft.) deep

    19.

    Check the outlet pipe periodically during the summer season to avoid clogging.

    19.

    Do not allow the slurry to dry or cake at the end of the outlet pipe.

    20.

    Repaint the gas holder (if it is of M.S. Sheet) from the outside every year with paint to prevent rusting. This will also prolong its life.

    20.

    Do not allow the gas holder (if it is made of M.S. Sheets) to rust, this will develop holes resulting in leakage of gas.

     
    Annexure- XI 

    Cost Benefit Analysis of KVIC Plant having an installed biogas generation capacity of 3 m³/day 
    (Amt. Rs.)
     

    a. Capital cost

     

    Gas holder and frame

    4500

    Piping and stove

    1750

    Civil engineering construction (tank, inlet and outlet, etc.)

    10000

    Total

    16250

    b. Annual expenditure

     

    The interest on investment @ 9% p.a.

    1462.50

    Depreciation on gas holder and frame @ 10% p.a.

    450

    Depreciation on piping and stove @ 5% p.a.

    87.50

    Depreciation on structure @ 5 %

    500

    Cost of painting, once a Year

    350

    Total

    2850

    c. Annual income

     

    Gas 3m³ per day @ Rs. 2.30 / m³ for 315 days 
    ( assuming initial 50 days of HRT)

    2173.50

    Manure (6 tons, composted) with refuse 15 tons @ Rs. 200 / tonne

    3000

    Total

    5173.50

    d. Net annual income (b - c)

    2323.50

     
    The net annual income of approximately Rs. 2300/- shows that the capital investment of  Rs. 16250/- can be recouped in about seven years. There are also incidental advantages of hygienic improvement, the absence of smoke and soot in gas burning, convenience in burning, and the increased richness of manure.

     

     Biomass Energy and Cogeneration:  

    Globally, India is in the fourth position in generating power through biomass and with a 

    huge potential, is poised to become a world  leader in the utilisation of biomass. 

    Biomass power projects with an aggregate  capacity of 773.3 MW through over 100 

    projects have been installed in the country. For the last 15 years, biomass power has 

    become an industry attracting annual investment of over Rs. 1,000 billion, generating 

    more than 09 billion unit of electricity per year. More than 540 million tons of crop and 

    plantation residues are produced every year  in India and a large portion is either 

    wasted, or used inefficiently. By using  these surplus agricultural residues, by 

    conservative estimates more than 16,000 MW of grid quality power could be 

    generated through Biomass. In addition, about 5,000 MW if power can be produced, if 

    all 550 sugar mills in the country switch over to modern techniques of cogeneration. 

    Thus the estimated biomass power potential is about 21,000 MW.

     

     
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
     

    Like

  • shankar
    shankar -

    Handbook of biogas ideal for indian conditions too Like

  • joyishkumar
    joyishkumar -

    Good comparison of methane yields from various feedstocks in the Biogas Handbook.

     

    Like

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