Status of Brick Kilns Stack Emission in Kathmandu Valley of Nepal

2020 ◽  
Vol 06 (3&4) ◽  
pp. 1-9 ◽  
Author(s):  
Anjay Kumar Mishra ◽  
Keyword(s):  
Kathmandu Valley ◽  
Brick Kilns

scholarly journals Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): emissions of particulate matter and sulfur dioxide from vehicles and brick kilns and their impacts on air quality in the Kathmandu Valley, Nepal

2019 ◽  
Vol 19 (12) ◽  
pp. 8209-8228 ◽  
Author(s):  
Min Zhong ◽  
Eri Saikawa ◽  
Alexander Avramov ◽  
Chen Chen ◽  
Boya Sun ◽  
...  
Keyword(s):  
Air Quality ◽  
Vehicle Emissions ◽  
Air Pollutant ◽  
Kathmandu Valley ◽  
So2 Emissions ◽  
Emissions Inventory ◽  
Brick Kilns ◽  
Pollutant Concentrations ◽  
Air Pollutant Concentrations ◽  
Local Emissions

Abstract. Air pollution is one of the most pressing environmental issues in the Kathmandu Valley, where the capital city of Nepal is located. We estimated emissions from two of the major source types in the valley (vehicles and brick kilns) and analyzed the corresponding impacts on regional air quality. First, we estimated the on-road vehicle emissions in the valley using the International Vehicle Emissions (IVE) model with local emissions factors and the latest available data for vehicle registration. We also identified the locations of the brick kilns in the Kathmandu Valley and developed an emissions inventory for these kilns using emissions factors measured during the Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE) field campaign in April 2015. Our results indicate that the commonly used global emissions inventory, the Hemispheric Transport of Air Pollution (HTAP_v2.2), underestimates particulate matter emissions from vehicles in the Kathmandu Valley by a factor greater than 100. HTAP_v2.2 does not include the brick sector and we found that our sulfur dioxide (SO2) emissions estimates from brick kilns are comparable to 70 % of the total SO2 emissions considered in HTAP_v2.2. Next, we simulated air quality using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) for April 2015 based on three different emissions scenarios: HTAP only, HTAP with updated vehicle emissions, and HTAP with both updated vehicle and brick kilns emissions. Comparisons between simulated results and observations indicate that the model underestimates observed surface elemental carbon (EC) and SO2 concentrations under all emissions scenarios. However, our updated estimates of vehicle emissions significantly reduced model bias for EC, while updated emissions from brick kilns improved model performance in simulating SO2. These results highlight the importance of improving local emissions estimates for air quality modeling. We further find that model overestimation of surface wind leads to underestimated air pollutant concentrations in the Kathmandu Valley. Future work should focus on improving local emissions estimates for other major and underrepresented sources (e.g., crop residue burning and garbage burning) with a high spatial resolution, as well as the model's boundary-layer representation, to capture strong spatial gradients of air pollutant concentrations.

scholarly journals Musculoskeletal Symptoms among the Brick Kiln Workers of Kathmandu Valley

2017 ◽  
Vol 7 (1) ◽  
pp. 7-11
Author(s):  
Tanweer Mikrani ◽  
Naresh Manandhar ◽  
Sunil Kumar Joshi
Keyword(s):  
Exposed Group ◽  
Musculoskeletal Symptoms ◽  
Control Group ◽  
Kathmandu Valley ◽  
Control Groups ◽  
Brick Kiln ◽  
Musculoskeletal Problem ◽  
Cross Sectional ◽  
Brick Kilns ◽  
And Control

Background: Brick kilns may pose threat to the environment and health of the workers and people residing around them. Health problems related to brick kilns are musculoskeletal, respiratory, digestive system, nutritional and skin disorders. Objective of this study was to find out the prevalence of musculoskeletal symptoms (problems) among brick kiln workers of Kathmandu valley. Methods: A cross sectional study was conducted in the brick kilns of Kathmandu valley from February to April 2015. Two hundred (200) workers were selected randomly from the sampled brick kilns of Kathmandu Valley as the exposed group and the equal number of grocery vendors from the surroundings of the brick kilns was included as the control group in term of exposure to ergonomic hazards. The data was collected using Nordic Musculoskeletal Questionnaire. Results: A majority of the respondents were Hindu by religion. The mean age of exposed group was 30.75 years and 33.25 years for control group. Male female ratios were 2.39:1 and 1.94:1 in exposed and control groups respectively. The highest prevalence of musculoskeletal problem was found on Shoulders followed by Lower back, Knee and Neck for exposed group. Conclusion: All musculoskeletal problems were significantly different between exposed and control groups. Compared to the control groups, brick kiln workers had almost 8 times more likely to experience shoulder problem and 7 times more low back pain. All musculoskeletal symptoms at any time during last 12 months were found higher in exposed group compared to the control group, which was statistically significant.

scholarly journals Wintertime aerosol optical and radiative properties in the Kathmandu Valley during the SusKat-ABC field campaign

2017 ◽  
Vol 17 (20) ◽  
pp. 12617-12632 ◽  
Author(s):  
Chaeyoon Cho ◽  
Sang-Woo Kim ◽  
Maheswar Rupakheti ◽  
Jin-Soo Park ◽  
Arnico Panday ◽  
...  
Keyword(s):  
Black Carbon ◽  
Urban Areas ◽  
Regional Scale ◽  
Temperature Drop ◽  
Absorption Efficiency ◽  
Radiative Properties ◽  
Kathmandu Valley ◽  
Carbonaceous Aerosols ◽  
Brick Kilns ◽  
Aerosol Mass

Abstract. Particulate air pollution in the Kathmandu Valley has reached severe levels that are mainly due to uncontrolled emissions and the location of the urban area in a bowl-shaped basin with associated local wind circulations. The AERONET measurements from December 2012 to August 2014 revealed a mean aerosol optical depth (AOD) of approximately 0.30 at 675 nm during winter, which is similar to that of the post-monsoon but half of that of the pre-monsoon AOD (0.63). The distinct seasonal variations are closely related to regional-scale monsoon circulations over South Asia and emissions in the Kathmandu Valley. During the SusKat-ABC campaign (December 2012–February 2013), a noticeable increase in both aerosol scattering (σs; 313  →  577 Mm−1 at 550 nm) and absorption (σa; 98  →  145 Mm−1 at 520 nm) coefficients occurred before and after 4 January 2013. This can be attributed to the increase in wood-burned fires due to a temperature drop and the start of firing at nearby brick kilns. The σs value in the Kathmandu Valley was a factor of 0.5 lower than that in polluted cities in India. The σa value in the Kathmandu Valley was approximately 2 times higher than that at severely polluted urban sites in India. The aerosol mass scattering efficiency of 2.6 m2 g−1 from PM10 measurements in the Kathmandu Valley is similar to that reported in urban areas. However, the aerosol mass absorption efficiency was determined to be 11 m2 g−1 from PM10 measurements, which is higher than that reported in the literature for pure soot particles (7.5 ± 1.2 m2 g−1). This might be due to the fact that most of the carbonaceous aerosols in the Kathmandu Valley were thought to be mostly externally mixed with other aerosols under dry conditions due to a short travel time from their sources. The σs and σa values and the equivalent black carbon (EBC) mass concentration reached up to 757 Mm−1, 224 Mm−1, and 29 µg m−3 at 08:00 LST (local standard time), respectively but decreased dramatically during the daytime (09:00–18:00 LST), to one-quarter of the morning average (06:00–09:00 LST) due to the development of valley winds and an atmospheric bounder layer. The σs and σa values and the EBC concentration remained almost constant during the night at the levels of 410 Mm−1, 130 Mm−1, and 17 µg m−3, respectively. The average aerosol direct radiative forcings over the intensive measurement period were estimated to be −6.9 ± 1.4 W m−2 (top of the atmosphere) and −20.8 ± 4.6 W m−2 (surface). Therefore, the high atmospheric forcing (i.e., 13.9 ± 3.6 W m−2) and forcing efficiency (74.8 ± 24.2 W m−2 τ−1) can be attributed to the high portion of light-absorbing aerosols in the Kathmandu Valley, as indicated by the high black carbon (or elemental carbon) to sulphate ratio (1.5 ± 1.1).

scholarly journals Brick Kilns in Kathmandu Valley: Current status, environmental impacts and future options

1970 ◽  
Vol 1 (1) ◽  
pp. 59-61 ◽  
Author(s):  
A. K. Raut
Keyword(s):  
Air Pollution ◽  
Cost Effective ◽  
Current Status ◽  
Kathmandu Valley ◽  
Brick Kiln ◽  
Environment Friendly ◽  
Alternative Technologies ◽  
Brick Kilns ◽  
The People ◽  
The Government

'Kathmandu Valley' is vulnerable to air pollution problem due to its topography, which restricts the wind movement and allows pollutants to remain within the valley. Brick kilns, operating in the Valley, are known to be a prime cause of air pollution. There are currently more than 125 brick kilns operating in Kathmandu valley deteriorating its air quality and degrading the health of the people living near the kilns. Recent studies have found that the concentration of particulate matter in the air in an area with brick kilns is three times higher when the kilns are operating than during the off-season. Similarly, the health of students studying at a school situated near a brick kiln was found to be significantly worse than that of students studying in a similar school but located in an area without brick kilns. Other environmental costs of the brick kilns are the reduction in the soil fertility, reduced visibility, drying ground water sources. The use of an old and inefficient technology called Bull's Trench kilns and low quality fuel are the main causes of the problem. Recently the government has decided to ban Bulls Trench brick kilns in Kathmandu in a year and a half. As a result, entrepreneurs are searching for environment friendly and cost effective alternative technologies. There are some technologies currently in practice in India like Vertical Shaft Brick Kiln, Fixed Chimney Kilns which are environment friendly and economically sound. Introduction to these technologies in Nepal can save both ecology and economy. Himalayan Journal of Sciences 1(1): 59-61, 2003

scholarly journals Overview of VOC emissions and chemistry from PTR-TOF-MS measurements during the SusKat-ABC campaign: high acetaldehyde, isoprene and isocyanic acid in wintertime air of the Kathmandu Valley

2016 ◽  
Vol 16 (6) ◽  
pp. 3979-4003 ◽  
Author(s):  
Chinmoy Sarkar ◽  
Vinayak Sinha ◽  
Vinod Kumar ◽  
Maheswar Rupakheti ◽  
Arnico Panday ◽  
...  
Keyword(s):  
Air Pollution ◽  
South Asia ◽  
Biomass Burning ◽  
Isocyanic Acid ◽  
Kathmandu Valley ◽  
Production Potential ◽  
Mixing Ratios ◽  
Brick Kilns ◽  
Ambient Concentrations ◽  
Tof Ms

Abstract. The Kathmandu Valley in Nepal suffers from severe wintertime air pollution. Volatile organic compounds (VOCs) are key constituents of air pollution, though their specific role in the valley is poorly understood due to insufficient data. During the SusKat-ABC (Sustainable Atmosphere for the Kathmandu Valley–Atmospheric Brown Clouds) field campaign conducted in Nepal in the winter of 2012–2013, a comprehensive study was carried out to characterise the chemical composition of ambient Kathmandu air, including the determination of speciated VOCs, by deploying a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS) – the first such deployment in South Asia. In the study, 71 ion peaks (for which measured ambient concentrations exceeded the 2σ detection limit) were detected in the PTR-TOF-MS mass scan data, highlighting the chemical complexity of ambient air in the valley. Of the 71 species, 37 were found to have campaign average concentrations greater than 200 ppt and were identified based on their spectral characteristics, ambient diel profiles and correlation with specific emission tracers as a result of the high mass resolution (m ∕ Δm  >  4200) and temporal resolution (1 min) of the PTR-TOF-MS. The concentration ranking in the average VOC mixing ratios during our wintertime deployment was acetaldehyde (8.8 ppb)  >  methanol (7.4 ppb)  >  acetone + propanal (4.2 ppb)  >  benzene (2.7 ppb)  >  toluene (1.5 ppb)  >  isoprene (1.1 ppb)  >  acetonitrile (1.1 ppb)  >  C8-aromatics ( ∼ 1 ppb)  >  furan ( ∼ 0.5 ppb)  >  C9-aromatics (0.4 ppb). Distinct diel profiles were observed for the nominal isobaric compounds isoprene (m ∕ z  =  69.070) and furan (m ∕ z  =  69.033). Comparison with wintertime measurements from several locations elsewhere in the world showed mixing ratios of acetaldehyde ( ∼  9 ppb), acetonitrile ( ∼  1 ppb) and isoprene ( ∼  1 ppb) to be among the highest reported to date. Two "new" ambient compounds, namely formamide (m ∕ z  =  46.029) and acetamide (m ∕ z  =  60.051), which can photochemically produce isocyanic acid in the atmosphere, are reported in this study along with nitromethane (a tracer for diesel exhaust), which has only recently been detected in ambient studies. Two distinct periods were selected during the campaign for detailed analysis: the first was associated with high wintertime emissions of biogenic isoprene and the second with elevated levels of ambient acetonitrile, benzene and isocyanic acid from biomass burning activities. Emissions from biomass burning and biomass co-fired brick kilns were found to be the dominant sources for compounds such as propyne, propene, benzene and propanenitrile, which correlated strongly with acetonitrile (r2 > 0.7), a chemical tracer for biomass burning. The calculated total VOC OH reactivity was dominated by acetaldehyde (24.0 %), isoprene (20.2 %) and propene (18.7 %), while oxygenated VOCs and isoprene collectively contributed to more than 68 % of the total ozone production potential. Based on known secondary organic aerosol (SOA) yields and measured ambient concentrations in the Kathmandu Valley, the relative SOA production potential of VOCs were benzene  >  naphthalene  >  toluene  >  xylenes  >  monoterpenes  >  trimethylbenzenes  >  styrene  >  isoprene. The first ambient measurements from any site in South Asia of compounds with significant health effects such as isocyanic acid, formamide, acetamide, naphthalene and nitromethane have been reported in this study. Our results suggest that mitigation of intense wintertime biomass burning activities, in particular point sources such biomass co-fired brick kilns, would be important to reduce the emission and formation of toxic VOCs (such as benzene and isocyanic acid) in the Kathmandu Valley.

scholarly journals Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): Emissions of particulate matter and sulfur dioxide from vehicles and brick kilns and their impacts on air quality in the Kathmandu Valley, Nepal

2018 ◽  
Author(s):  
Min Zhong ◽  
Eri Saikawa ◽  
Alexander Avramov ◽  
Chen Chen ◽  
Boya Sun ◽  
...  
Keyword(s):  
Air Quality ◽  
Vehicle Emissions ◽  
Air Pollutant ◽  
Kathmandu Valley ◽  
Emissions Inventory ◽  
Brick Kilns ◽  
Pollutant Concentrations ◽  
Testing Experiment ◽  
Air Pollutant Concentrations ◽  
Local Emissions

Abstract. Air pollution is one of the most pressing environmental issues in the Kathmandu Valley, where the capital city of Nepal is located. We estimated emissions from two of the major source types in the valley (vehicles and brick kilns) and analyzed the corresponding impacts on regional air quality. First, we estimated the on-road vehicle emissions in the valley using the International Vehicle Emission (IVE) model with local emission factors and the latest available data for vehicle registration. We also identified the locations of the brick kilns in the Kathmandu Valley and developed an emissions inventory for these kilns using emission factors measured during the Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE) field campaign in April 2015. Our results indicate that the commonly-used global emissions inventory, the Hemispheric Transport of Air Pollution (HTAP_v2.2), underestimates particulate matter emissions from vehicles in the Kathmandu Valley by a factor greater than 100. In addition, brick kilns account for nearly 70 % of total sulfur dioxide (SO2) emissions from all sectors considered in HTAP_v2.2. Next, we simulated air quality using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) for April 2015 based on three different emission scenarios: HTAP only, HTAP with updated vehicle emissions, and HTAP with both updated vehicle and brick kilns emissions. Comparisons between simulated results and observations indicate that the model underestimates observed surface elemental carbon (EC) and SO2 concentrations under all emissions scenarios. However, our updated estimates of vehicle emissions significantly reduced model bias for EC, while updated emissions from brick kilns improved model performance in simulating SO2. These results highlight the importance of improving local emissions estimates for air quality modeling. We further find that model overestimation of surface wind leads to underestimated air pollutant concentrations in the Kathmandu Valley. Future work should focus on improving local emissions estimates for other major and underrepresented sources (e.g., crop residue burning and garbage burning) with a high spatial resolution, as well as the model's boundary-layer representation, to capture strong spatial gradients of air pollutant concentrations.

scholarly journals Overview of VOC emissions and chemistry from PTR-TOF-MS measurements during the SusKat-ABC campaign: high acetaldehyde, isoprene and isocyanic acid in wintertime air of the Kathmandu Valley

2015 ◽  
Vol 15 (17) ◽  
pp. 25021-25087 ◽  
Author(s):  
C. Sarkar ◽  
V. Sinha ◽  
V. Kumar ◽  
M. Rupakheti ◽  
A. Panday ◽  
...  
Keyword(s):  
Air Pollution ◽  
South Asia ◽  
Biomass Burning ◽  
Isocyanic Acid ◽  
Kathmandu Valley ◽  
Production Potential ◽  
Mixing Ratios ◽  
Brick Kilns ◽  
Ambient Concentrations ◽  
Tof Ms

Abstract. The Kathmandu Valley in Nepal suffers from severe wintertime air pollution. Volatile organic compounds (VOCs) are key constituents of air pollution, though their specific role in the Valley is poorly understood due to insufficient data. During the SusKat-ABC (Sustainable Atmosphere for the Kathmandu Valley-Atmospheric Brown Clouds) field campaign conducted in Nepal in the winter of 2012–2013, a comprehensive study was carried out to characterize the chemical composition of ambient Kathmandu air, including the determination of speciated VOCs by deploying a Proton Transfer Reaction Time of Flight Mass Spectrometer (PTR-TOF-MS)–the first such deployment in South Asia. 71 ion peaks (for which measured ambient concentrations exceeded the 2 σ detection limit) were detected in the PTR-TOF-MS mass scan data, highlighting the chemical complexity of ambient air in the Valley. Of the 71 species, 37 were found to have campaign average concentrations greater than 200 ppt and were identified based on their spectral characteristics, ambient diel profiles and correlation with specific emission tracers as a result of the high mass resolution (m/Δm > 4200) and temporal resolution (1 min) of the PTR-TOF-MS. The highest average VOC mixing ratios during the measurement period were (in rank order): acetaldehyde (8.8 ppb), methanol (7.4 ppb), acetone (4.2 ppb), benzene (2.7 ppb), toluene (1.5 ppb), isoprene (1.1 ppb), acetonitrile (1.1 ppb), C8-aromatics (~ 1 ppb), furan (~ 0.5 ppb), and C9-aromatics (0.4 ppb). Distinct diel profiles were observed for the nominal isobaric compounds isoprene (m/z = 69.070) and furan (m/z = 69.033). Comparison with wintertime measurements from several locations elsewhere in the world showed mixing ratios of acetaldehyde (~ 9 ppb), acetonitrile (~ 1 ppb) and isoprene (~ 1 ppb) to be among the highest reported till date. Two "new" ambient compounds namely, formamide (m/z = 46.029) and acetamide (m/z = 60.051), which can photochemically produce isocyanic acid in the atmosphere, are reported in this study along with nitromethane (a tracer for diesel exhaust) which has only recently been detected in ambient studies. Two distinct periods were selected during the campaign for detailed analysis: the first was associated with high wintertime emissions of biogenic isoprene, and the second with elevated levels of ambient acetonitrile, benzene and isocyanic acid from biomass burning activities. Emissions from biomass burning and biomass co-fired brick kilns were found to be the dominant sources for compounds such as propyne, propene, benzene and propanenitrile which correlated strongly with acetonitrile (r2 > 0.7), a chemical tracer for biomass burning. The calculated total VOC OH reactivity was dominated by acetaldehyde (24.0 %), isoprene (20.2 %) and propene (18.7 %), while oxygenated VOCs and isoprene collectively contributed to more than 68 % of the total ozone production potential. Based on known SOA yields and measured ambient concentrations in the Kathmandu Valley, the relative SOA production potential of VOCs were: benzene > naphthalene > toluene > xylenes > monoterpenes > trimethyl-benzenes > styrene > isoprene. The first ambient measurements from any site in South Asia of compounds with significant health effects such as isocyanic acid, formamide, acetamide, naphthalene and nitromethane have been reported in this study. Our results suggest that mitigation of intense wintertime biomass burning activities, in particular point sources such biomass co-fired brick kilns, would be important to reduce the emission and formation of toxic VOCs (such as benzene and isocyanic acid) in the Kathmandu Valley and improve its air quality.

scholarly journals Wintertime Aerosol Optical and Radiative Properties in the Kathmandu Valley during the SusKat-ABC Field Campaign

2017 ◽  
Author(s):  
Chaeyoon Cho ◽  
Sang-Woo Kim ◽  
Maheswar Rupakheti ◽  
Jinsoo Park ◽  
Arnico Panday ◽  
...  
Keyword(s):  
Urban Areas ◽  
Regional Scale ◽  
Temperature Drop ◽  
Absorption Efficiency ◽  
Radiative Properties ◽  
Kathmandu Valley ◽  
Carbonaceous Aerosols ◽  
Noticeable Increase ◽  
Brick Kilns ◽  
Aerosol Mass

Abstract. Particulate air pollution in the Kathmandu Valley has reached severe levels that are mainly due to uncontrolled emissions and the location of the urban area in a bowl-shaped basin with associated local circulations. The AERONET measurements from December 2012 to August 2014 revealed a mean aerosol optical depth (AOD) of approximately 0.3 at 675 nm during winter, which is similar to that of the post-monsoon but half of that of the pre-monsoon AOD (0.63). The distinct seasonal variations are closely related to regional-scale monsoon circulations over South Asia and emissions in the Kathmandu Valley. During the SusKat-ABC campaign (December 2012–February 2013), a noticeable increase of both aerosol scattering (σs; 313 → 522 Mm−1 at 550 nm) and absorption (σa; 98 → 145 Mm−1 at 520 nm) coefficients occurred before and after January 4, 2013. This can be attributed to the increase of wood-burned fires due to a temperature drop and the start of firing at nearby brick kilns. The σs value in the Kathmandu Valley was a factor of 0.5 lower than that in polluted cities in India. The σa value in the Kathmandu Valley was approximately 2 times higher than that at severely polluted urban sites in India. The aerosol mass scattering efficiency of 2.6 m2 g−1 in the Kathmandu Valley is similar to that reported in urban areas. However, the aerosol mass absorption efficiency was determined to be 11 m2 g−1, which is higher than that reported in the literature for pure soot particles (7.5 ± 1.2 m2 g−1). This might be due to the fact that most of the carbonaceous aerosols in the Kathmandu Valley were thought to be fresh aerosols, mostly externally mixed with other aerosols under dry conditions due to a short travel time from their sources. The σs and σa values and the equivalent black carbon (EBC) mass concentration reached up to 757 Mm−1, 224 Mm−1, and 29 µg m−3 at 08 LST, respectively but decreased dramatically during the daytime (09–18 LST), to one quarter of the morning average (06–09 LST) due to the development of valley winds and an atmospheric bounder layer. The σs and σa values and the EBC concentration remained almost constant during the night at the level of 410 Mm−1, 130 Mm−1, and 17 µg m−3, respectively. The average aerosol direct radiative forcings over the intensive measurement period were estimated to be −6.9 ± 1.4 W m−2 (top of the atmosphere) and −20.8 ± 4.6 W m−2 (surface). Therefore, the high atmospheric forcing (i.e., 13.9 ± 3.6 W m−2) and forcing efficiency (74.8 ± 24.2 W m−2 τ−1) can be attributed to the high portion of light-absorbing aerosols in the Kathmandu Valley, as indicated by the high BC (or elemental carbon) to sulphate ratio (1.5 ± 1.1).

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