UNEP Characterization of Waste Agricultural Biomass for Energy Applications Training on Technologies for Converting Waste Agricultural Biomass into Energy Organized by United Nations Environment Programme (UNEP DTIE IETC) September, 2013 San Jose, Costa Rica Surya Prakash Chandak Senior Programme Officer International environmental Technology Centre Division of Technology, Industry and Economics Osaka, Japan

UNEP International Environmental Technology Centre 2 Why Characterisation of WAB Characterization of WAB provides essential information for: Selection of WAB2E technology System design Assessment of operational performance Provides data for tendering

UNEP International Environmental Technology Centre 3 Characterization of waste agricultural biomass Parameters of characterization Visual characterization Moisture content Chemical Composition Calorific value Specific characterization parameters

UNEP International Environmental Technology Centre 4 Characterization of waste agricultural biomass Visual characterization SourceWaste StreamVisual Observations Commercial FacilitiesFruit and vegetable waste High moisture (estimated to be %), sometimes putrified, mixed with packing hay Corporate FarmsRice huskClean, stacked in heaps, approximate volume …m3 Jaggery PlantsBagasseMoist waste (estimated moisture 50%), scattered around, some spread on ground for sun-drying, mixed with barbojo Private farms--

UNEP International Environmental Technology Centre 5 Characterization of waste agricultural biomass Moisture content Two ways of reporting Moisture content on wet basis (MC wb ) Moisture content on dry basis (MC db ) Relationship between MC wb and MC db

UNEP International Environmental Technology Centre 6 Characterization of waste agricultural biomass Chemical composition – Ultimate Analysis Component Percent by weight (dry basis) CarbonHydrogenOxygenNitrogenSulphurAsh Wheat Straw Rice Straw Rice Husk < Bagasse < Hard Wood < Soft Wood < Corn Cob Cotton stalk < Anthracite coal

UNEP International Environmental Technology Centre 7 Characterization of waste agricultural biomass Chemical composition – Proximate Analysis Component Percent by weight (dry basis) Volatile Matter (%dry ash free basis)Fixed Carbon (%dry ash free basis) Ash (% dry basis) Wheat Straw Rice Straw Rice Husk Bagasse Wood Peanut shell Corn Cob Cotton stalk Anthracite coal

UNEP International Environmental Technology Centre 8 Characterization of waste agricultural biomass Energy Content Three expressions: Higher Heating Value (HHV) or Gross Calorific Value (GCV) Lower Heating Value (LHV) or Net Calorific Value (NCV) Usable Heat Content HHV – Total energy generated from combustion including the heat of condensation of water vapor – represents maximum theoretical potential energy LHV -- Total energy generated from combustion less the heat of condensation of water vapor – represents maximum realizable energy UHC – LHV less the sensible heat of the combustion products – represents actual usable energy

UNEP International Environmental Technology Centre Characterization of waste agricultural biomass  Relationships between heating values –HHV of wet biomass = (1-m)HHV D –LHV = (1-m)HHV D - (latent heat)  (moisture content in product gas per kg fuel) = (1-m)HHV D –  [m  (1-m)  H ] –Utilizable heat content = LHV -  [(mass fraction)  (C P )] all products  (T exht - T amb ) 9 where m is the fractional moisture content in biomass

UNEP International Environmental Technology Centre Characterization of waste agricultural biomass  Estimation of Higher Heating Value of WAB –Usually, heating values of biomass materials are determined through direct experimental measurement by means of a device called bomb calorimeter –Alternative to the practical measurements, approximate estimations for HHV D could be made through analytical equations that are derived based on fuel composition –Based on ultimate analysis Three models: –Model – X: HHV=0.352xC xH – 0.111xO xN xS –Model – Y: HHV=0.349xC xH – 0.103xO xN xS – 0.021A –Model – Z: HHV=0.341xC xH – 0.120xO xN xS – 0.015A –HHV – Higher Heating Value in MJ/Kg –C,H,O,N,S,A are the % mass fractions of Carbon, Hydrogen, Oxygen, Nitrogen, Sulfur and Ash respectively in dry biomass. –Try matching with the formula !! Q = 337C (H - O/8) + 93S 10

UNEP International Environmental Technology Centre Characterization of waste agricultural biomass  Estimation of Higher Heating Value of WAB Based on ultimate analysis 11 Biomass Fuel Composition (% by weight)HHV D (MJ/kg) CHONSAsh Model X Model Y Model Z Paddy Straw Paddy Husk Corn Cob Bagasse Cotton Stalk Hard Wood Soft Wood Miscanthus Barley Straw Wheat Straw Lignite Anthracite Coal

UNEP International Environmental Technology Centre Characterization of waste agricultural biomass  Estimation of Higher Heating Value of WAB Based on ultimate analysis 12 Biomass constituent / Chemical equation Ultimate Analysis (%) HHV D (MJ/kg) CHO Model -X Model -Y Model- Z Cellulose / (C 6 H 10 O 5 ) x Hemicelluloses / (C 5 H 8 O 4 ) y Lignin / (C 9 H 10 O 3 (CH 3 O) 0.9 – 1.7 ) z 58.7 – – – – – – 25.7

UNEP International Environmental Technology Centre Characterization of waste agricultural biomass Estimation of Higher Heating Value of WAB Based on proximate analysis Three Models  Model A: HHV = xVM xFC – xA  Model B: HHV = xVM xFC  Model C: HHV = x(VM+FC) – HHV – Higher Heating Value in MJ/Kg VM, FC,A are the % mass fractions of Volatile Matter, Fixed Carbon and Ash respectively in dry biomass. 13

UNEP International Environmental Technology Centre Characterization of waste agricultural biomass  Estimation of Higher Heating Value of WAB Based on proximate analysis 14 Biomass FuelComposition (% by weight)HHV D (MJ/kg) VM (ash free) FC (ash free) Ash Model- A Model- B Model- C Bagasse Coconut coir Coconut shell Coir pith Corn cob Corn stalks Groundnut shell Paddy Husk Paddy Straw Wheat Straw Peanut Shell Cotton Stalk

UNEP International Environmental Technology Centre  Effects of Moisture on Heating Value Characterization of waste agricultural biomass 15

UNEP International Environmental Technology Centre 16 HAPPY WORKING ON CHARACTERIZATION OF WASTE AGRICULTURAL BIOMASS

UNEP International Environmental Technology Centre 17 THANK YOU For further information: