Presentation on theme: "Better Air Quality 2004 EMISSION OF POLYCYCLIC AROMATIC HYDROCARBONS AND PARTICULATE MATTER FROM DOMESTIC COOKING USING COAL Nghiem Trung Dung Institute."— Presentation transcript:
Better Air Quality 2004 EMISSION OF POLYCYCLIC AROMATIC HYDROCARBONS AND PARTICULATE MATTER FROM DOMESTIC COOKING USING COAL Nghiem Trung Dung Institute for Environmental Science and Technology Hanoi University of Technology, 1 Dai Co Viet road, Hanoi, Vietnam Hoang Xuan Co, Pham Ngoc Ho and Do Quang Huy Faculty of Environmental Sciences, Hanoi University of Sciences Vietnam National University, 334 Nguyen Trai road, Hanoi, Vietnam Agra, India, 6-8 December 2004
INTRODUCTION PAHs: Polycyclic Aromatic Hydrocarbons, or Polynuclear Aromatics (PNA), organic compounds composed of fused benzene rings Sources: Natural: Forest fires, volcanoes Anthropogenic: Incomplete combustion of organic materials, industries A major group of carcinogens and mutagens in the environment. Human exposure: via food, water, air or direct contact with materials containing PAHs. PAHs in the air: Distributed between particulate and vapor phases PAHs on particulate: Exchangeable fraction and non - exchangeable fraction Distribution of PAHs between vapor phase and exchangeable fraction of particulate phase depends on: Vapor pressure of PAHs Ambient temperature Particulate concentration, Particulate size, surface area and the nature of particulate
PAHs distribution between particulate and vapor phases as a function of temperature Source: Yasuda (1995)
SOURCE SAMPLING Method followed: U.S. EPA Modified Method 5 (U.S.EPA,1986) - Gas-phase PAHs were collected on XAD-2 resin - Particulate-phase PAHs were collected on glass fiber filter Particulate matter were iso-kinetically sampled Sampling train:
Source sampling train for PAHs Heated Filter Box Condenser Dry Gas Meter XAD-2 (30 g) 4 Impingers in Ice Bath Probe Line Stack Flue gas in Flue gas out 1. Condensate knockout 2. 100 ml of distilled water 3. Empty 4. 350 g of silica gel
Sampling information Sample code Fuel informationSample information Moisture (%) Ash (%) Burning rate (kg/h) Amount Burnt (g) Time (min) Volume a (m 3 ) Flue gas temp. ( o C) Collected PM (mg) PM con. a (mg/m 3 ) C1 126.96.36.199 498652.28179.04.21.8 C27981203.86875.823.36.0 C38481204.30672.735.78.3 C48281074.27274.423.65.5 C58481455.10073.621.84.3 C68781384.18679.021.55.1 Note: a- Normal conditions (25 o C, 1 atm)
Analytical procedure, US. EPA Method TO-13 Soxhlet extraction with DCM Particulate matter or XAD-2 Centrifugation (if needed) Evaporation to dryness by N 2 gas Dewater by sodium sulphate PAHs Fraction Rotary evaporation to nearly dryness Solvent exchange to cyclohexane (1ml) Clean-up with silica gel 1) 25 ml, n-pentane 2) 25 ml, n-pentane-DCM, (6:4, V:V) Add 1 ml of cyclohexane Analysis by GC/MS Aliphatic fraction
Comparison of PAHs emission factors among different fuels Source: Coal briquettes, wood, charcoal (Kim Oanh, 1999) Kerosene (Kim Oanh, 2002) Sawdust (Dung, 2004)
Comparison of PAHs emission rates among different fuels Source: Coal briquettes, wood, charcoal (Kim Oanh, 1999) Kerosene (Kim Oanh, 2002) Sawdust (Dung, 2004)
CONCLUSION Emission of individual PAHs from domestic cooking using coal was monitored. Emission factor, emission rate as well as concentration of the total PAHs were determined to be 62.0 mg kg-1, 25.1mg h-1 and 4.0 g Nm-3 respectively. All detected PAHs, except for benzo(b)fluoranthene, were found to be present in both gas and PM phases of smoke. Gas phase contributed 70% of the total PAHs in terms of emission factor. Very high percentage of BaP in smoke emitted from domestic cooking using coal was observed.
References Dung, N.T., Co, H.X., Ho, P.N. and Huy, D.Q., 2004. Emission of Polycyclic Aromatic Hydrocarbons and Particulate Matter from Domestic Cooking Using Sawdust. Science and Technology (in press) Kim Oanh, N.T., Nghiem, L.H., Phyu, Y.L., 2002. Emission of Polycyclic Aromatic Hydrocarbons, Toxicity and Mutagenicity from Domestic Cooking Using Sawdust Briquettes, Wood, and Kerosene. Environmental Science and Technology 36, 833-839. Kim Oanh, N.T., Reutergårdh L.B., Dung, N.T., 1999. Emission of Polycyclic Aromatic Hydrocarbons and Particulate Matter from Domestic Combustion of Selected Fuels. Environmental Science and Technology 33, 2703-2709. U.S. EPA, 1986. Modified Method 5 (Method 0010) Sampling Train, Revision 0, September 1986. U.S. EPA, Washington, DC. U.S. EPA, 1988. Compendium of Methods for Determination of Toxic Organic Compounds in Ambient Air, Revision 1.0, June 1988. U.S. EPA/600/4-89/017, U.S. EPA, Washington, DC. Yasuda, K., 1995. Stack Sampling Technique for PAHs. Materials of the Third ASEAN Workshop on Air Pollution Monitoring and Analysis with Emphasis on PAHs, ERTC, Bangkok, Thailand.