Biomass burning in India and pollution
A spatially resolved biomass burning data set, and related emissions of SO2 and aerosol chemical constituents was constructed for India, for 1996–1997 and extrapolated to the INDOEX period (1998–1999). Sources included biofuels (wood, crop waste and dungcake) and forest fires (accidental, shifting cultivation and controlled burning). PM emission factors were compiled from studies of Indian cooking stoves and from literature for open burning. BC and OM emissions were estimated from these, accounting for combustion temperatures in cooking stoves. SO2 emission factors were based on fuel sulphur content and reported literature measurements. Biofuels accounted 93% of total biomass consumption (577MTyr_1), with forest fires contributing only 7%. This is in contrary to global patterns, where forest fires are the primary and biofuels a negligible contributor. The biofuel-mixvaried across different regions, with a national average of 56 : 21 :23% for fuelwood, crop waste and dung-cake, respectively. The biomass consumption densities were high over the east-coast and north India, and low over central and western India. Sulphur dioxide emissions were 7% from biomass combustion, compared to 93% from fossil fuel combustion. This is in contrast to previous biomass contribution estimates of 19–23%, and results from more realistic SO2 emission factors, especially for dung-cake. Dung-cake results in higher SO2 emissions from its high sulphur content compared to other biomass types. The biomass combustion in India resulted in 2.04 Tg yr_1 of PM2.5 emissions, equal to that from fossil fuel combustion. Fuelwood was major contributor to particulate emissions from biomass combustion. The PM2.5 emission fluxes were high in east-coast and north India. The ‘‘inorganic fraction’’ of PM2.5 emissions was 0.86 Tg yr_1. Water-soluble inorganic ions, rather than mineral ash, are expected to constitute this ‘‘inorganic fraction’’, which must be verified through measurements. In India, biomass combustion was the major source of carbonaceous aerosol emissions, accounting 0.25 Tg yr_1 of BC (72% of total) and 0.94 Tg yr_1 of OM (76% of total). The low combustion temperatures in the domestic biomass cooking stoves result in particulate emissions with larger carbonaceous fraction, compared to hightemperature coal combustion. Among biomass, fuelwood and crop waste were primary contributors to BC emissions, while dung-cake and forest fires were primary contributors to OM emissions. While emissions from fossil fuel combustion arelocalised to large point sources (utilities, refineries and petrochemicals, cement and fertilisers) and major cities, emissions from biomass combustion are area sources spread all over India. The spatial variation in biomass consumption was accounted in estimating emissions. However, rural per capita consumption of biofuels are representative of 1984–1992 and must be updated in future studies. Measurements of emission factors of SO2, size resolved aerosols and their chemical constituents for Indian cooking stoves are needed to improve the present estimates. Note: Detailed tables of fuel- and state-wise emissions, and emission maps of SO2, PM2.5, BC, OM and ‘‘Inorganic Fraction’’ are posted on Aerosol Research Laboratory website at http://www.iitb.ac.in/Bcese/arl/ References Ahuja, D.R., Joshi, V., Smith, K.R., Venkataraman, C., 1987. Thermal performance and emission characteristics of unvented biomass-burning cookstoves: a proposed standard method for evaluation. Biomass 12, 247–270. Akimoto, H., Narita, H., 1994. Distribution of SO2, NOx and CO2 emissions from fuel combustion and industrial activities in Asia with 11_11 resolution. Atmospheric Environment 28, 213–215. Allen, A.G., Miguel, A.H., 1995. Biomass burning in the Amazon: characterisation of the ionic component of aerosols generated from flaming and smouldering rainforest and Savannah. Environmental Science and Technology 29, Andreae, M.O., Browell, E.V., Garstang, M., Gregory, G.L., Harriss, R.C., Hill, G.F., Jacob, D.J., Pereira, M.C., Sachse, G.W., Setzer, A.W., Dias, P.L.S., Talbot, R.W., Torres, A.L., Wofsy, S.C., 1988. Biomass-burning emissions and associated haze layers over Amazonia. Journal of Geophysical Research 93, 1509–1527. Arndt, R.L., Carmichael, G.R., Streets, D.G., Bhatti, N., 1997. Sulphur dioxide emissions and sectoral contribution to sulphur deposition in Asia. Atmospheric Environment 31, 1553–1582. Ballard-Tremeer, G., 1997. Emissions of rural wood-burning cooking devices. Ph.D. Thesis, School of Mechanical Engineering, University of the Witwatersrand, Johannesburg- 2050, South Africa. Ballard-Tremeer, G., Jawurek, H.H., 1996. Comparison of five rural wood-burning cooking devices: efficiencies and emissions. Biomass and Bioenergy 11, 419–430. Butcher, S.S., Ellenbecker, M.J., 1982. Particulate emission factors for small wood and coal stoves. Journal of Air Pollution Control Association 32, 380–384. Butcher, S.S., Sorenson, E., 1979. A study of wood stove particulate emissions. Journal of Air Pollution Control Association 29, 724–728. Cachier, H., Ducret, J., Bremond, M.-P., Yoboue, V., Lacaux, J.-P., Gaudichet, A., Baudet, J., 1991. Biomass burning aerosols in a Savannah region of the Ivory Coast. In: Levine, J.S. (Ed.), Global Biomass Burning: Atmospheric, Climatic, and Biospheric Implications. The MIT Press, Cambridge, London, pp. 174–180. CIGR, 1999. CIGR Handbook of agricultural engineering, Vol. V, Energy and biomass engineering. The American Society of Agricultural Engineers, 2950 Niles Road, St Joseph, MI 49085-9659, USA. Cooke, W.F., Wilson, J.J.N., 1996. A black carbon aerosol model. Journal of Geophysical Research 101, 19395–19409. Cooper, J.A., 1980. Environmental impact of residential wood combustion emissions and its implications. Journal of Air Pollution Control Association 30, 855–861. Countess, R.J., Cadle, S.H., Groblicki, P.J., Wolff, G.T., 1981. Chemical analysis of size-segregated samples of Denver’s ambient particulate. Journal of Air Pollution Control Association 31, 247–252. Dasch, J.M., 1982. Particulate and gaseous emissions from wood-burning fire places. Environmental Science and Technology 16, 639–645. Dickerson, R.R., Andreae, M.O., Campos, T., Mayol-Bracero, O.L., Neusuess, C., Streets, D.G., 2001. Emissions of black carbon and carbon monoxide from south Asia. Journal of Geophysical Research (submitted for publication). Einfeld, W., Ward, D.E., Hardy, C.C., 1991. Effects of fire behaviour on prescribed fire smoke characteristics: a case study. In: Levine, J.S. (Ed.), Global Biomass Burning: Atmospheric, Climatic, and Biospheric Implications. The MIT Press, Cambridge, London, pp. 412–419. EPA, 1998. Residential wood combustion technology review, Vol. 1. Technical report. EPA-600/R-98-174a. US EPA, Office of Research and Development, Washington, DC 20460. FSI, 1998. State of forest report 1997. Forest Survey of India, Ministry of Environment and Forests, Dehra Dun, India. 710 M.S. Reddy, C. Venkataraman / Atmospheric Environment 36 (2002) 699–712 Garg, A., Shukla, P.R., Bhattacharya, S., Dadhwal, V.K., 2001. Sub-region (district) and sector level SO2 and NOx emissions for India: assessment of inventories and mitigation. Atmospheric Environment 35, 703–713. GoI, 1992. Census of India 1991, series-1, Final population totals, Vol. I, Paper 1 of 1992. Ministry of Home Affairs, Government of India, New Delhi.