JOL RNAL OF SCIENCE & TECHNOLOGV * DETER MINATION OF EMISSION FACTORS FOR DOMESTIC SOURCES USING BIOMASS FUELS XAC DINH HE SO P H A T THAI CHO CAc NGUON DAN SINH SU" DUNG NHIEN LIEU SINH KHOI Nghiem T[.]
JOL RNAL OF SCIENCE & TECHNOLOGV * DETER.MINATION OF EMISSION FACTORS FOR DOMESTIC SOURCES USING BIOMASS FUELS XAC DINH HE SO P H A T T H A I CHO CAc NGUON DAN SINH SU" DUNG NHIEN LIEU SINH KHOI Nguyen I iet Thang National Inslilule of Labour Protection Nghiem Trung Dung Hanoi University of Science and Technology ABSTRACT The emission of selected air pollutants for domestic sources using three biomass fuels being the eucalyptus, mango and rice straw were studied The fuels were burnt as the way they are used foi routine domestic cooking Samples of particulate matter (PM) were collected isokinetically using a stack sampler of CASELLA and following US EPA modified method Gaseous pollutants in the flue gas were measured using a monitor of Drager MSI - PR02 The levels of these air pollutants in ttie ambient air in surrounding area were also measured using a monitor of QUEST EVM - Series Tt>e rice straw Is found to have the highest temperature of the flue gas (75 °C) but the lowest burning rate (151 g/h) among the fuels studied The emission factors of PM, CO, CO^, SO2 for domestic sources using the fuels were determined The emission factors obtained in this study are in the same range with those in other countries TOM TAT Mirc phit thii mdt sd chit d nhiem khdng tir cic ngudn dan sinh sir dijng nhien lieu sint) khdi gdm bach din xoai va ram, da dwac nghien ciru Nhien lieu dwac ddt giong nhw thwc t^ dun niu smh hoat Miu bui (PM) dwac liy mot cich ding ddng sir dung thiit bi liy miu CASELLA vi theo f^hwong phip da cai tiin ciia US EPA Cic chit d nhiim dang thai dwac bing thiit bi Drager MSI - PR02 Ndng cic chit khdng xung quanh cung dwac do, sir dung thiit bt QUEST EVM - Series Trong cic nhien lieu nghien ciru, ram cd nhiet thii cao nhit (75 °C) nhwng cd tdc chiy thip nhit (151 g/h) He sd phit thil PM, CO, CO2, SO2 tie ngudn din smh sir dung cic loai nhien lieu ndi tren da dwac xic dinh He sd phat thai thu dwac nghien ciru niy nim cung mdt dii so vdt cic nghien ciru d mdt sd nwdc khic I INTRODUCTION emissions However, data on emission factors for domestic cooking using the biomass fuels developed in Vietnamese conditions are still scarce This study is, therefore, aimed at the development of the emission factors of selected air pollutants from domestic cooking using the biomass fuels Biomass fuels are being widely used for domestic cooking in \"ietnani The combustion of the biomass fuels emits different air pollutants including those regulated by QCVN" 05:2009/BI\MT {]] These'air pollutants can cause health effects lo the people In addition, the biomass fuels are normally used bv the poor people in narrow kitchens with the poor ventilation resulting in higher health risks, especially for women, children and the elderly In order to assess the potential of health effects from cooking smoke, total emission of air pollutants need to be estimated And one of effective tools for doing so in manv countries is the application of emission factors An emission factor is a tool that is used to estimate air pollutanl emissions to the atmosphere It relates the quantity of pollutants released from a source to some activity associated with those II MATERIALS AND METHODS Three biomass fuels commonly used for domestic cooking, namely the eucalyptus, mango and rice straw, were selected for this study The eucalyptus and mango were collected from Phuc Yen, Vinh Phuc province while the rice straw was from Van Khe, Mc Linh Flanoi The fuel wood was sticks (25-30 cm long 2-3 cm thick) produced from logs of the eucalyptus and mango The fuels were burnt as the wav thev are used for routine domestic cooking The wood fuels (the eucalyptus and 32 .r ^«i.wr acii! '.CE& TECHNOLOGY * No.82A-201l mango) were bumt without stoking during the test while the rice straw was bumt with stoking to keep the combustion stable No spillage of the smoke or flame blown-away was observed Different parameters related to the fuels and burning conditions including moisture and sulfur contents of the fuels, the temperature of the flue gas (at the traverse point), the temperature of the flame, unburnt mass of the fuels were measured The information on the fuels and combustion is provided in Table I Sampling Point | r I 9001 using a stack sampler of CASELLA (UK) in accordance to US EPA modified method [3] The small stack diameter (11 cm) could accommodate only one traverse point with the position detennined by US EPA method [4] The sampling probe was thus fi.xed and sampling port was closed using insulation material to minimize disturbances to the gas flow During the sampling, the filter box and the sampling probe were heated at around 120 "C Gaseous pollutants in the flue gas were measured using a monitor of Drager MSI PR02 (Germany) In order to obtain the net concentrations of the air pollutants in the flue gas, the levels of these pollutants in the ambient air in surrounding area were also monitored using a monitor of QUEST EVM - Series (US) III RESULTS AND DISCUSSIONS I 4281: 35wn "t" V^'atchjng dj> h- -A Figure Hood and sampling port A hood (Figure 1) was used to capture the flue gas from the cookstove The hood was designed and installed following the standard method presented in the previous studv [2] Sampling'measuring was done through a port in the hood flue pipe The port was located at and flue pipe diameters downstream and upstream from disturbances, rcspectivelv to ensure the unifonn How of the flue gas and representative sampling of PM [3] Samples of PM were collected isokineticallv on the ulass fibre filters 3.1.; lilluns Seven burning batches per fuel were conducted The summary information of the fuels and combustion are presented in Table The rice straw is found to have the highest temperature of the flue gas (75 °C) but the lowest burning rate (151 g/h) among the fuels studied Besides the heat values, this can be explained as that the rice straw had better burning condition as it was burnt in terms of smaller pieces It means that its burning had better oxygen supply/contact i.e better combustion with higher flame resulting in higher temperature However, its burning process was slowed down by the stoking during the test (while other fuels were not stoked) leading to the lowest buming rate For the wood fuels, buming conditions can be considered to be the same However, the mango seemed to have a better combustion than that of the eucalv plus as its burring rate and temperature of the flue gas were higher The moisture content of the fuels may be the reason for this: the moisture content of the mango (7.4%o) was lower than that of the eucalyptus (14.1%)) J O I RNAL OF SCIENCE & TECHNOLOGY Sample code BDI BD2 BD3 BD4 BD5 BD6 BD7 ^Fuel : — ^ c -Jl CXI - CX2 CX3 CX4 CX5 CX6 CX7 Rl R2 R3 R4 R5 R6 R7 Table Summary of the fuels and Moisture Sample Amount Amount content ("o) mass (g) unburnt (g) bumt (g) 500.30 65.73 434.57 63.41 500.30 436.89 500.30 61.28 439.02 14 = 1.0 500.02 65.79 434.23 500.20 51.05 439.15 500.24 64.01 436.23 432.24 500.34 68.10 Average 500.91 39 64 461.27 500.42 53.54 ! 446.88 464.17 500.02 35.85 '' 7.4=0.4 500.48 46.38 454.10 500.67 59.12 -' 441.55 45.49 454.91 500.40 500.91 39.64 454.91 Averaac 500.40 75.88 424.52 500.80 72.85 427.95 500.32 425.36 74.96 15.6=0.6 500.50 70.87 429.63 500.52 72.92 427.60 500.23 72.55 427.68 500.13 72.63 427.50 Averaiic 3.2 Emission factor Emission factors of PM CC C"()^ and SO for domestic sources using the eucalyptus, mango and rice straw were determined Results obtained are presented in Table It is known that the emission factor is dependent on dilTerenl factors including the fuel composition and the burning condition It means that the comparisons mav be relative However, the emission factors of PM CO CO: and SOobtained in this studv can be considered to be in the same range with those in others |2 6, 7] Higher emission factor of PM of the rice straw mav be explained as that this fuel is lighter and was burnt in terms of smaller pieces resulting in more panicles suspended The burning conditions for the wood fuels in this studv were similar lierefore as anticipated, the emission factor of SO of the euealvptus was higher than that of the mango because S content of the fomier |l).6