Total Suspended Particulate Emission Research Articles

Identification and Characterization of Particulate Matter Concentrations at Construction Jobsites

The identification and characterization of particulate matter (PM) concentrations from construction site activities pose major challenges due to the diverse characteristics related to different aspects, such as concentration, particle size and particle composition. Moreover, the characterization of particulate matter is influenced by meteorological conditions, including temperature, humidity, rainfall and wind speed. This paper is part of a broader investigation that aims to develop a methodology for assessing the environmental impacts caused by the PM emissions that arise from construction activities. The objective of this paper is to identify and characterize the PM emissions on a construction site with different aerodynamic diameters (PM2.5, PM10, total suspended particulates (TSP)), based on an exploratory study. Initially, a protocol was developed to standardize the construction site selection criteria, laboratory procedures, field sample collection and laboratory analysis. This protocol was applied on a multifamily residential building construction site during three different construction phases (earthworks, superstructure and finishings) aimed at measuring and monitoring PM concentrations arising from construction activities. The particulate matter was characterized in different particle sizes. Results showed that the higher TSP emissions arising from construction activities provoked environmental impacts. Some limitations to the results were identified, especially with regards the need for a detailed investigation about the influence of different construction phases on PM emissions. The findings provided significant knowledge about various situations, serving as a basis for improving the existing methodology for particulate material collection on construction sites and the development of future studies on the specific construction site phases.

Field wind tunnel testing of two silt loam soils on the North American Central High Plains

Abstract Wind erosion is a soil degrading process that threatens agricultural sustainability and environmental quality globally. Protecting the soil surface with cover crops and plant residues, practices common in no-till and reduced tillage cropping systems, are highly effective methods for shielding the soil surface from the erosive forces of wind and have been credited with beneficial increases of chemical and physical soil properties including soil organic matter, water holding capacity, and wet aggregate stability. Recently, advances in biofuel technology have made crop residues valuable feed stocks for ethanol production. Relatively little is known about cropping systems effects on intrinsic soil erodibility, the ability of the soil without a protective cover to resist the erosive force of wind. We tested the bare, uniformly disturbed, surface of long-term tillage and crop rotation research plots containing silt loam soils in western Kansas and eastern Colorado with a portable field wind tunnel. Total Suspended Particulate (TSP) were measured using glass fiber filters and respirable dust, PM10 and PM2.5, were measured using optical particle counters sampling the flow to the filters. The results were highly variable and TSP emission rates varied from less than 0.5 mg m−2 s−1 to greater than 16.1 mg m−2 s−1 but all the results indicated that cropping system history had no effect on intrinsic erodibility or dust emissions from the soil surfaces. We conclude that prior best management practices will not protect the soil from the erosive forces of wind if the protective mantle of crop residues is removed.

Air quality impact assessment of multiple open pit coal mines in northern Colombia

The coal mining region in northern Colombia is one of the largest open pit mining regions of the world. In 2009, there were 8 mining companies in operation with an approximate coal production of ∼70 Mtons/year. Since 2007, the Colombian air quality monitoring network has reported readings that exceed the daily and annual air quality standards for total suspended particulate (TSP) matter and particles with an equivalent aerodynamic diameter smaller than 10 μm (PM₁₀) in nearby villages. This paper describes work carried out in order to establish an appropriate clean air program for this region, based on the Colombian national environmental authority requirement for modeling of TSP and PM(10) dispersion. A TSP and PM₁₀ emission inventory was initially developed, and topographic and meteorological information for the region was collected and analyzed. Using this information, the dispersion of TSP was modeled in ISC3 and AERMOD using meteorological data collected by 3 local stations during 2008 and 2009. The results obtained were compared to actual values measured by the air quality monitoring network. High correlation coefficients (>0.73) were obtained, indicating that the models accurately described the main factors affecting particle dispersion in the region. The model was then used to forecast concentrations of particulate matter for 2010. Based on results from the model, areas within the modeling region were identified as highly, fairly, moderately and marginally polluted according to local regulations. Additionally, the contribution particulate matter to the pollution at each village was estimated. Using these predicted values, the Colombian environmental authority imposed new decontamination measures on the mining companies operating in the region. These measures included the relocation of three villages financed by the mine companies based on forecasted pollution levels.

Chemical Mass Balance Source Apportionment of Ambient Total Suspended Particulate Matters Near Jhuoshuei River in Central Taiwan

Based on an investigation of ambient total suspended particulate (TSP) matter concentrations, this study not only evaluates how the TSP levels deteriorate the air quality near Jhuoshuei River in central Taiwan, but also demonstrates that the monsoon season profoundly influences ambient TSP concentrations. Samples of ambient TSP obtained from representative areas in target areas during monsoon and other seasons in 2005–2006 were collected for use in receptor modeling. A chemical mass balance model version 8 (CMB8) developed by the United States Environmental Protection Agency, was implemented based on TSP emission information from version 5.1 of the Taiwan Emission Data System (TEDS5.1) and a source profile from SPECIATE3.2. CMB8 model estimates indicated that windblown soil coming from the Jhuoshuei riverbed largely contributed to the receptor site during the monsoon season. Statistical analysis revealed that metal species appearing during the monsoon season have a higher correlation with each other than during other seasons. The well-known fact that these elements are emitted from soil suggests that the soil source significantly contributes to TSP concentration at downwind sampling sites during the monsoon season. Moreover, the concentration of TSPs at downwind sites is significantly higher than that at upwind site during monsoons, posing a potential risk to human health in the downwind residential communities.

Estimation of air pollutant emission loads from construction and operational activities of a port and harbour in Mumbai, India

Port causes environmental and health concerns in coastal cities if its operation and development are not made environmentally compatible and sustainable. An emission inventory is necessary to assess the impact of port projects or growth in marine activity as well as to plan mitigation strategies. In this study, a detailed emission inventory of total suspended particulate (TSP) matter, respirable particulate matter (PM(10)), sulphur dioxide (SO(2)) and oxides of nitrogen (NO(x)) for a port having operation and construction activities in parallel is compiled. The study has been done for 1 year. Results show that the maximum contribution of emission of air pollutants in the port area was from TSP (68.5%) and the minimum was from SO(2) (5.3%) to the total pollutants considered in this study. Total TSP emission from all activities of the port was 4,452 tyr(-1) and PM(10) emission was 903 tyr(-1) in the year 2006. Re-suspension of dust from paved roads was the major contributor of TSP and PM(10) in the road transport sector. Construction activities of the port had contributed 3.9% of TSP and 7.4% of PM(10) to total emission of particulate matter. Of the total particulate emissions from various port activities approximately 20% of TSP could be attributed to PM(10). The sectoral composition indicates that major contribution of SO(2) emission in the port was from maritime sector and major contribution of NO(x) was from road transport sector.

Field Tests of a Particulate Impaction Curtain on Emissions from a High-Rise Layer Barn

Particulate matter (PM) emission rates from two high-rise layer barns (barns 1 and 2) were measured from 1 August 2004 to 31 January 2005. A commercial particulate impaction curtain (PIC) was installed parallel to the first floor sidewalls and upstream of the exhaust fans of barn 2 for PM reduction by impaction. Tapered element oscillating microbalance (TEOM) monitors were used to measure PM10 (PM <10 µm) concentrations of barn 1 exhaust air and before and after the PIC in barn 2. Concentrations of total suspended particulate (TSP) were monitored at each location two to three times per week with a gravimetric sampler. Prior to the six-month full-scale test, a preliminary test of the PIC was conducted at a single continuous sidewall fan of barn 2 for 10 d. Results of the preliminary test indicated that the PIC reduced PM10 emission by 33% to 49% and TSP emission by 62% to 72%. In the full-scale test, average untreated daily mean PM10 emissions were 30 ±13 and 35 ±33 mg d-1 hen-1 (mean ±standard deviation) from barns 1 and 2, respectively. The mean treated PM10 emission rate was 22 ±23 mg d-1 hen-1 and was decreased by 41% based on measurements before and after the PIC. However, some dilution occurred due to backflow through non-operating fans. The TSP emission rate of barn 2 was 27 ±23 g d-1 AU-1, 39% lower than barn 1, which was 44 ±29 g d-1 AU-1. However, some important practical issues currently hinder the use of PIC in high-rise layer barns.

Burning characteristics and emission products related to metallic content in incense

This study mainly compared particulate emission factors of nine popular incense. The influence of metallic contents upon the burning rate, ash and particulate emission factors of combustion was discussed. The contents of Ca and K were the highest among all metallic elements in the raw materials of the incense (the geometric mean contents 8.7 and 2.5 mg g −1, respectively), followed by Al, Mg, Fe, Na (0.1–1.0 mg g −1) and Ba, then Sr, Mn, Cu and Zn (<0.01–0.1 mg g −1). Most calcium existed as inorganic salts, such as CaCO 3. Under the same burning conditions, the particulate generation rates are similar (0.50 mg min −1 ± 9%) among different types of incense—the shorter the combustion duration of a stick, the lower the total suspended particulate emission. Additionally, with the same incense weight burned, the greater the emission of ash is, the lower the emission of suspended particulate. It is recommended that consumers select incense which produces more ash, hence less particulate, to minimize the threat to their’ health. Additionally, when the total metallic content (with Ca as the major component) was lower than 2% of the raw materials, properly increasing the total metallic content (from 0.5 to 2.0%) can effectively reduce the level of particulates (about 40%) during the combustion.

GSTM1andCYP1A1Polymorphisms, Tobacco, Air Pollution, and Lung Cancer: A Study in Rural Thailand

The Lampang Province is situated in the northern region of Thailand. Incidence rates of lung cancer are high for Asian standards, particularly in women. This study was conducted to quantify the risk of lung cancer associated with exposures prevalent in the area and to investigate possible interactions with genetic susceptibility. The presence of several large open-cast coal mines from 1955 close to electricity-generating plants was a particular focus of concern. Two-hundred and eleven cases of primary lung cancers diagnosed in 1993 to 1995 and residents in the province were recruited at the Lampang Provincial Hospital (main referral center for treatment of the disease). Two sets of controls, frequency-matched to the cases by sex and age, were recruited (a) from the resident population (202 interviewed) and (b) from patients admitted to the hospital for diseases predominantly unrelated to tobacco smoking (211 interviewed). Sociodemographic information, complete residential history, and characteristics of the household (place of cooking, cooking fuel, and heating fuels), occupational history, and history of tobacco smoking were obtained by interview. Cases and controls ( approximately 50% of the population-based series) provided a blood sample. A point source air pollution exposure index was calculated for each village/township reported in residential histories based on the linear distance from the Mae Moh Center (the area of the electricity-generating plants), the year-specific gaseous (SO(2) and NO(2)) or total suspended particulate emissions from the Mae Moh Power Plant, and the percentage of wind from the center. Odds ratios (OR) for the disease associated with categorical variables were estimated within unconditional logistic regression. Extraction of genomic DNA and genotyping of variants in CYP1A1 and GSTM1 were conducted to assess the extent of modification of risk by these genes that are involved in the metabolism of polycyclic aromatic hydrocarbons, a common component of the exposures. Overall, there was no evidence of relevant differences in the socioeconomic level of the three groups. The two control sets were similar with respect to lifelong tobacco habit and were subsequently pooled in analyses. Never-smokers were 7% of men and 33% of women. Smoking of local traditional products unfiltered and high in tar content is a common habit in the rural female population. ORs associated with smoking increased with duration of the habit and average daily amount, being 4.9 [95% confidence interval (95% CI), 2.5-9.7] for smokers of > or =7 cigarettes/d and 3.3 (95% CI, 1.7-6.2) for duration of 41 years or longer compared with nonsmokers. Smoking of local products was associated with an independent OR of 3.1 (95% CI, 1.7-5.6) adjusted for lifelong cumulative amount of tobacco smoked. Although most smokers had the habit for at least 16 years, the daily consumption was low compared with Western standards. Other potential sources of exposure to lung carcinogens (emission from the power-generating plants and domestic burning of coal and wood for cooking and heating) were not associated with increased risk of lung cancer. None of the three polymorphisms examined increased the risk of lung cancer or modified the risk associated with tobacco smoking. In this rural population, 96% of male and 64% of female lung cancer incidence were explained by tobacco smoking. None of the potential sources of air pollution deriving from the combustion of coal and wood, or polymorphisms in the CYP1A1 gene or deletion of the GSTM1 had an effect on the risk of lung cancer, either together or separately.

Emission rate formulae for surface iron ore mining activities

A study was carried out at three surface iron ore mines to determine the total suspended particulate emission rate and to develop the formula for the emission rate of various surface iron ore mining activities. The study covered various mining activities and locations including waste loading and unloading, iron ore loading and unloading, screening plant, exposed waste dump, stock yard, exposed pit surface, transport road and haul road. A set of 10 formulae was developed to calculate the total suspended particulate emission rate of various surface iron ore mining activities. The emission of gaseous pollutants (sulphor dioxide and oxides of nitrogen) was also evaluated but was found negligible for various mining activities, and emission rates were determined for overall mine only. The developed formulae were validated with the measured emission data at another surface iron ore mine. The accuracy of the activity-wise emission rates calculated using the developed formulae was found to vary from 92 to 97% of actual field measurement data. The developed formulae for determination of emission rate from various surface iron ore mining activities will help in predicting air quality status through air quality modelling and designing effective mitigative measures for sensitive areas during the planning stage of a proposed mine.

Emissions of Particulate and Gaseous Pollutants within the Keelung Harbor Region of Taiwan

The Keelung port, which is located on the northern tip of Taiwan, right next to the Taipei metropolitan area, is an important international harbor. However, any air pollutants generated from the Keelung port region, immediately travel to the neighboring Keelung city, and greatly impact the residents' daily life and the quality of their environment. This study has investigated and quantified pollution emissions, from the Keelung port region, between 1997 and 2002. Emissions from major air pollution sources were estimated. The estimated results indicated that total TSP (total suspended particles) emissions had significantly increased, from 5221 ton/yr in 1997 to 262 687 ton/yr in 2002, due to the greatly increased volume of sand imported into Keelung Harbor. Quantities of other emissions, such as SO(2), NO(2), CO and HC remained stable and were 440, 207, 78 and 25 ton/yr, respectively, on average, with variations within 7% over the previous six-year period. By examining the emissions from pollution sources, it was found that TSP emissions mainly originated from re-suspension of dust, due to both vehicle movement and the sand unloading process; this accounted for over 99% of the total TSP emissions produced in the port region. About 80% of the total SO(2) emissions originated from the main ships' engines within the Keelung port region, due to the use of fuel with a high sulfur content. In addition, loading/unloading machines within the port region were the major sources of NO(2), CO and HC pollution emissions, which comprised 54, 58 and 66% of the total emissions of these pollutants, respectively. TSP emissions from Keelung port were much higher than from the neighboring Keelung city; hence, alleviating TSP emissions should be the first priority for air pollution reduction within both the port of Keelung and Keelung city.

Levels of Lead in Urban Soils from Selected Cities in a Central Region of the Philippines (7 pp)

Levels of Lead in Urban Soils from Selected Cities in a Central Region of the Philippines (7 pp)

Intake fractions of industrial air pollutants in China: Estimation and application

Intake fractions, an emissions-intake relationship for primary pollutants, are defined and are estimated in order to make simple estimates of health damages from air pollution. The sulfur dioxide (SO 2) and total suspended particles (TSP) intake fractions for five cities of China are estimated for the four main polluting industries—electric power generation, mineral (mostly cement) products industry, chemical process industry and metallurgical industry (mainly iron and steel smelting). The Industrial Source Complex Long Term (ISTLT3) model is used to simulate the spatial distribution of incremental ambient concentrations due to emissions from a large sample of site-specific sources. Detailed population distribution information is used for each city. The average intake fractions within 50 km of these sources are 4.4 × 10 - 6 for TSP, and 4.2 × 10 - 6 for SO 2, with standard deviations of 8.15 × 10 - 6 and 9.16 × 10 - 6 , respectively. They vary over a wide range, from 10 - 7 to 10 - 5 . Although the electric power generation has been the focus of much of the air pollution research in China, our results show that it has the lowest average intake fraction for a local range among the four industries, which highlights the importance of pollutant emissions from other industrial sources. Sensitivity analyses show how the intake fractions are affected by the source and pollutant characteristics, the most important parameter being the size of the domain. However, the intake fraction estimates are robust enough to be useful for evaluating the local impacts on human health of primary SO 2 and TSP emissions. An application of intake fractions is given to demonstrate how this approach provides a rapid population risk estimate if the dose-response function is linear without threshold, and hence can help in prioritizing pollution control efforts.

Effectiveness of street sweeping and washing for controlling ambient TSP

Effectiveness of street sweeping and washing (S/W) for controlling ambient “total suspended particles (TSP)” was evaluated by TSP measurements and determining silt load from active traffic streets. A modified regenerative-air vacuum sweeper (RAVS) and a washer were used in this study. The sweeper made a pass followed by the washer. The S/W efficiencies (ηs,ηT) were obtained based on the experimental data of silt loading and TSP. It was found that the direct impact of sweeping on ambient TSP emissions was short-lived lasting no more than 3–4 h. When a vacuum sweeper and a washer, respectively, did a good job collecting or cleaning the visible fine particles on roads, the method of S/W tested in this work was effective at removing the sources of the road dust particles. This paper concludes that street sweeping followed by washing was found to offer a measurable reduction in TSP emission potentials. Typically, the reduction efficiency of ambient TSP is up to 30%. Finally, correlated with ηS (based on silt loading), a useful equation is proposed to estimate the S/W efficiency, ηT (based on TSP) with a standard error of ±20%. It seems feasible to predict the reduction efficiency of ambient TSP controlled by the regenerative-air vacuum sweeper and washer used in this work for engineering applications. Effects of traffic volume and wind velocity on the S/W efficiencies are also discussed in the paper.

A SIMULATED APPROACH TO ESTIMATING PM10 AND PM2.5 CONCENTRATIONS DOWNWIND FROM COTTON GINS

Cotton gins are required to obtain operating permits from state air pollution regulatory agencies (SAPRA), whichregulate the amount of particulate matter that can be emitted. Industrial Source Complex Short Term version 3 (ISCST3) isthe Gaussian dispersion model currently used by some SAPRAs to predict downwind concentrations used in the regulatoryprocess in the absence of field sampling data. The maximum ambient concentrations for PM10 and PM2.5 are set by theNational Ambient Air Quality Standard (NAAQS) at 150 .g/m3 and 65 .g/m3 (24 h average), respectively. Some SAPRAs usethe NAAQS concentrations as property line concentrations for regulatory purposes. This article reports the results of a uniqueapproach to estimating downwind PM10 and PM2.5 concentrations using Monte Carlo simulation, the Gaussian dispersionequation, the Hino power law, and a particle size distribution that characterizes the dust typically emitted from cotton ginexhausts. These results were then compared to a 10 min concentration (C10) and the concentrations that would be measuredby an FRM PM10 and PM2.5 sampler. The total suspended particulate (TSP) emission rate, particle size distributions, andsampler performance characteristics were assigned to triangular distributions to simulate the real-world operation of the ginand sampling systems. The TSP emission factor given in AP-42 for cotton gins was used to derive the PM mass emission ratefrom a 40 bale/h plant. The Gaussian equation was used to model the ambient TSP concentration downwind from the gin.The performance characteristics for the PM10 and PM2.5 samplers were then used to predict what the measured concentrationwould be for two PSD conditions. The first PSD assumption was that the mass median diameter (MMD) and geometricstandard deviation (GSD) were constant at 12 .m and 2, respectively, and the second scenario assigned a triangulardistribution to the MMD and GSD of {15, 20, 25} .m and {1.8, 2.0, 2.2}, respectively. The results show that the PM2.5 fractionof the dust emitted under either PSD condition was negligible when compared to the NAAQS for PM2.5 of 65 .g/m3. The resultsalso demonstrate that correcting for wind direction changes within the hour using the power law reduces the ambientconcentration by a factor of 2.45.

Emission estimates and trends (1990–2000) for megacity Delhi and implications

A comprehensive emission inventory for megacity Delhi, India, for the period 1990–2000 has been developed in support of air quality, atmospheric chemistry and climate studies. It appears that SO2 and total suspended particles (TSP) are largely emitted by thermal power plants (∼68% and ∼80%, respectively), while the transport sector contributes most to NOx, CO and non-methane volatile organic compound (NMVOC) emissions (>80%). Further, while CO2 has been largely emitted by power plants in the past (about 60% in 1990, and 48% in 2000), the contribution by the transport sector is increasing (27% in 1990 and 39% in 2000). NH3 and N2O are largely emitted from agriculture (∼70% and ∼50%, respectively), and solid waste disposal is the main source of CH4 (∼80%). In the past TSP abatement to improve air quality has largely focused on traffic emissions; however, our results suggest that it would be most efficient to also reduce TSP emissions by power plants. We also assessed the potential large-scale transport of the Delhi emissions based on 10-day forward trajectory calculations. The relatively strong growth of NOx emissions indicates that photochemical O3 formation in the regional environment may be increasing substantially, in particular in the dry season. During the summer, on the other hand, convective mixing of air pollutants may reduce regional but increase large-scale, i.e. hemispheric effects.

CONCENTRATION AND EMISSIONS OF AMMONIA AND PARTICULATE MATTER IN TUNNEL–VENTILATED BROILER HOUSES UNDER SUMMER CONDITIONS IN TEXAS

Total suspended particulate (TSP) concentrations, ammonia (NH3) concentrations, and ventilation rates weremeasured in four commercial, tunnelventilated broiler houses in June through December of 2000 in Brazos County, Texas.TSP and NH3 concentrations ranged from 7,387 to 11,387 .g m3 and 2.02 to 45 ppm, respectively. Ammonia concentrationexhibited a correlation with the age of the birds. Mass median diameters (MMD) of the TSP samples were between 24.0 and26.7 .m aerodynamic equivalent diameter. MMD increased with bird age. The mass fraction of PM10 in the TSP samples wasbetween 2.72% and 8.40% with a mean of 5.94%. Ventilation rates were measured between 0.58 and 89 m3 s1. Measuredconcentrations of PM10 and ammonia were multiplied by the measured ventilation rates to calculate emission rates for PM10and ammonia. Ammonia emission rates varied from 38 to 2105 g hr1. TSP emission rates and PM10 emission rates rangedfrom 7.0 to 1673 g hr1 and 0.58 to 99 g hr1, respectively. Emission rates for ammonia and particulate matter increased withthe age of the birds. Most of the PM in the commercial broiler houses was large enough to be captured by the human or poultryrespiratory system prior to being inhaled into the lungs.

The application of GIS to air quality analysis in Taichung City, Taiwan, ROC

This paper presents a preliminary study for the evaluation of transport-related air pollution situations in an urban area. The authors utilize a geographic information system (GIS) which integrates a vehicle emission model, pollutant dispersion model, backward trajectory model and related databases to estimate the emissions and spatial distribution of traffic pollutants in Taichung, Taiwan, ROC. The model not only can analyze the current pollution situations, but also can predict the emissions influenced by changes in specific traffic conditions or management policies. The results show that there are higher CO emissions around downtown areas in Taichung City, and the areas along Highway No.1 sustain higher NOx, SOx and TSP pollutions. Although the segment length of Highway No.1 within Taichung City is not very long, it contributes a significant portion of total suspended particulate (TSP), nitrogen oxides (NOx), and sulfur oxides (SOx) emissions to this area. Furthermore, predictions of several hypothetical scenarios indicate that the major effect of upgrading motorcycles is the reduction of TSP emission by more than 10%, while increasing average traffic speed of city roads may reduce more than 14% of CO emissions.

Greenhouse Implications of Household Stoves: An Analysis for India

▪ Abstract It is commonly assumed that biomass fuel cycles based on renewable harvesting of wood or agricultural wastes are greenhouse-gas (GHG) neutral because the combusted carbon in the form of CO2is soon taken up by regrowing vegetation. Thus, the two fifths or more of the world's households relying on such fuels are generally not thought to play a significant role in GHG emissions, except where the wood or other biomass they use is not harvested renewably. This review examines this assumption using an emissions database of CO2, CO, CH4, NMHC, N2O, and total suspended particulate emissions from a range of household stoves in common use in India using six biomass fuels, kerosene, liquefied petroleum gas, and biogas. Because typical biomass stoves are thermally inefficient and divert substantial fuel carbon to products of incomplete combustion, their global warming commitment (GWC) per meal is high. Depending on time horizons and which GHGs are measured, the GWC of a meal cooked on a biomass stove can actually exceed that of the fossil fuels, even if based on renewably harvested fuel. Biogas, being based on a renewable fuel and, because it is a gas, being combusted with high efficiency in simple devices, has by far the lowest GWC emitted at the stove per meal and is indicative of the advantage that upgraded fuels made from biomass have in moving toward sustainable development goals. There are a number of policy implications of this work, including revelation of a range of win-win opportunities for international investment in rural energy development that would achieve cost-effective GHG reduction as well as substantial local benefits.

EVALUATION OF STATIC PRESSURE DROPS AND PM10 AND TSP EMISSIONS FOR MODIFIED 1D-3D CYCLONES

Five modifications of a standard 1D3D cyclone were tested and compared against the standard 1D3D designin the areas of particulate emissions and static pressure drop across the cyclone. The modifications to the 1D3D designincluded a 2D2D inlet, a 2D2D air outlet, a D/3 trash exit, an expansion chamber with a D/3 trash exit, and a tapered airoutlet duct. The 1D3D modifications that exhibited a significant improvement in reducing both PM10 and total suspendedparticulate (TSP) emissions were the designs with the 2D2D inlet and air exhaust combined with either the conical D/3tail cone or the expansion chamber. In reference to the standard 1D3D cyclone, the average reduction in PM10 emissionswas 24 to 29% with a 29 to 35% reduction observed in TSP emissions. The modifications with the tapered air outlets didnot show any significant improvements in controlling PM10 emissions. However, the modification with the tapered airoutlet/expansion chamber combination exhibited statistical significance in reducing TSP emissions by 18% compared tothe 1D3D cyclone. All modifications tested exhibited lower static pressure drops than the standard 1D3D.

Characterization and problems of indoor pollution due to cooking stove smoke

Findings from the five groups of matched houses, each using either cattle dung, wood, coal, kerosene or liquid petroleum gas (LPG) as cooking fuels are presented with emphasis on cross comparison of indoor pollution levels during the cooking period. The houses using LPG were considered as controls. The characterization of pollution was made by measurements of total suspended particulates (TSP), carbon monoxide, nitrogen dioxide, formaldehyde, sulfur dioxide and particle sizing of TSP, which were further analysed for the evaluation of levels of polycyclic aromatic hydrocarbons (PAHs). A correlation between the pollutants as a function of fuel type has also been looked for. The study revealed that 50–80% of the TSP emissions from biomass and coal-burning cooking stoves were in a respirable fraction of ≤2 μm size and that a large amount of the PAHs (> 75%) belonged to this fraction only. Air quality biomass-using houses was the worst among the users of the five aforementioned fuels and levels were relatively high. The findings stress that a conserted effort towards a solution should be made as a large fraction of the world's population regularly uses biomass as a prime domestic fuel. The problems associated with cooking stoves in India and immediate research needs are outlined.