Concentration of atmospheric pollutants in the gaseous emissions of medical waste incinerators

The purpose of this paper is to quantify the production of medical waste from a general hospital and to evaluate the atmospheric pollutant concentrations in gaseous emissions associated with its incineration. A 3.8 kg (bed.day)-1 production of medical waste was estimated for 1998; its incineration is related with an ash production of 0.3-0.4 kg (bed.day)-1. The concentrations of atmospheric pollutants were estimated using emission factors, comparing the effluents with and without control of atmospheric pollutants. The calculated concentrations were compared with the emission limits established by Portuguese legislation. The results indicate that, if there is no control of atmospheric pollutants, their concentrations exceed the established limits. This is observed even if correct operation and maintenance procedures are used. The emission concentrations of dioxins are higher than the Portuguese emission limit, which is particularly worrying due to the high toxicity of some of these compounds. Generally, it is possible to reduce pollutant concentrations if appropriate control equipment is used. The conclusions obtained clearly justify the great concern regarding air pollution associated with medical waste incinerators currently operating in Portugal.     

Concentration of Atmospheric Pollutants in the Gaseous Emissions of Medical Waste Incinerators

ABSTRACT

The purpose of this paper is to quantify the production of medical waste from a general hospital and to evaluate the atmospheric pollutant concentrations in gaseous emissions associated with its incineration. A 3.8 kg (bed.day)^-1 production of medical waste was estimated for 1998; its incineration is related with an ash production of 0.3-0.4 kg (bed.day)^-1. The concentrations of atmospheric pollutants were estimated using emission factors, comparing the effluents with and without control of atmospheric pollutants. The calculated concentrations were compared with the emission limits established by Portuguese legislation. The results indicate that, if there is no control of atmospheric pollutants, their concentrations exceed the established limits. This is observed even if correct operation and maintenance procedures are used. The emission concentrations of dioxins are higher than the Portuguese emission limit, which is particularly worrying due to the high toxicity of some of these compounds. Generally, it is possible to reduce pollutant concentrations if appropriate control equipment is used. The conclusions obtained clearly justify the great concern regarding air pollution associated with medical waste incinerators currently operating in Portugal.     

Air quality impact due to scrap-metal handling on a sea port: A wind tunnel experiment

Emissions from cargo unloading and handling activities in sea ports can be of special importance, particularly in case of proximity to dense urban populations. In this sense, the main purpose of this work was to develop and implement a set of technical solutions intended to reduce the emissions and dispersion of particles resulting from scrap-metal handling on one of the most important Portuguese sea ports.The analysis of the atmospheric flow within the discharging berth was carried out in the Wind Tunnel Laboratory of the Department of Environment and Planning, at the University of Aveiro (Portugal). Laser sheet and hot wire anemometry techniques were applied. Two possible solutions were proposed, consisting in the use of windbreaks located upwind of the scrap-metal piles and a barrier of containers positioned downwind. Both flow visualisation and velocity-measuring techniques confirm a higher efficiency in the reduction of suspended particulate matter by using the containers plus the windbreaks. This combined solution is responsible for an important reduction on the emissions from the scrap-metal piles under typical meteorological conditions for this area, offering a good compromise between cost, time needed for implementation and efficiency.     

Forecasting human exposure to atmospheric pollutants in Portugal – A modelling approach

Air pollution has become one main environmental concern because of its known impact on human health. Aiming to inform the population about the air they are breathing, several air quality modelling systems have been developed and tested allowing the assessment and forecast of air pollution ambient levels in many countries. However, every day, an individual is exposed to different concentrations of atmospheric pollutants as he/she moves from and to different outdoor and indoor places (the so-called microenvironments). Therefore, a more efficient way to prevent the population from the health risks caused by air pollution should be based on exposure rather than air concentrations estimations. The objective of the present study is to develop a methodology to forecast the human exposure of the Portuguese population based on the air quality forecasting system available and validated for Portugal since 2005. Besides that, a long-term evaluation of human exposure estimates aims to be obtained using one-year of this forecasting system application. Additionally, a hypothetical 50% emission reduction scenario has been designed and studied as a contribution to study emission reduction strategies impact on human exposure.To estimate the population exposure the forecasting results of the air quality modelling system MM5-CHIMERE have been combined with the population spatial distribution over Portugal and their time-activity patterns, i.e. the fraction of the day time spent in specific indoor and outdoor places. The population characterization concerning age, work, type of occupation and related time spent was obtained from national census and available enquiries performed by the National Institute of Statistics. A daily exposure estimation module has been developed gathering all these data and considering empirical indoor/outdoor relations from literature to calculate the indoor concentrations in each one of the microenvironments considered, namely home, office/school, and other indoors (leisure activities like shopping areas, gym, theatre/cinema and restaurants). The results show how this developed modelling system can be useful to anticipate air pollution episodes and to estimate their effects on human health on a long-term basis. The two metropolitan areas of Porto and Lisbon are identified as the most critical ones in terms of air pollution effects on human health over Portugal in a long-term as well as in a short-term perspective. The coexistence of high concentration values and high population density is the key factor for these stressed areas. Regarding the 50% emission reduction scenario, the model results are significantly different for both pollutants: there is a small overall reduction in the individual exposure values of PM₁₀ (<10 μg m^?3 h), but for O₃, in contrast, there is an extended area where exposure values increase with emission reduction. This detailed knowledge is a prerequisite for the development of effective policies to reduce the foreseen adverse impact of air pollution on human health and to act on time.     

Air Pollutant Emissions from the Incineration of Hospital Wastes The Alberta Experience

Since the early seventies, hospital waste incineration has been an ever increasing issue in Alberta because of the emissions of particles, hydrochloric acid and chlorine which result from burning plastic-rich hospital waste. These stack emissions were measured from various hospital incinerators in the Province of Alberta and most were found to be above the standards adopted by the Alberta Department of Environment. Compliance with particulate and HC1 emission standards are mandatory in order to receive final approval for a hospital incinerator in Alberta. Adequate control measures are available to meet Alberta Environment requirements for hospital incinerator emissions.     

Current and future emissions of selected heavy metals to the atmosphere from anthropogenic sources in Europe

Current atmospheric emissions of As, Cd, Cr, Ni, and Pb (reference year 2000) from major anthropogenic sources in Europe are presented in this paper. Combustion of fuels in stationary sources was the main emission source for As, Cd, Cr, and Ni (more than a half of the total anthropogenic emissions), while combustion of gasoline was the main source of for lead. There is a continuous reduction of heavy metal emissions in Europe during the last 40 years. Better knowledge of heavy metal sources, emissions, pathways, and fate in the environment, and progress in developing efficient emission control equipment has resulted in more efficient regulatory efforts to curb heavy metal emissions from anthropogenic sources very substantially. There is a potential for further reduction of these emissions until the year 2010 up to about 40% for As, Cd, Cr, and Ni and about 57% for Pb, as estimated within various emission scenarios presented in the paper.     

PCDD/PCDF congener profiles in soil and herbage samples collected in the vicinity of a municipal waste incinerator before and after pronounced reductions of PCDD/PCDF emissions from the facility

Congener profiles are the fractional distribution of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) congeners in an environmental release, or in an environmental or biological sample. In 1999, an adaptation to the EU legislation on pollutant emissions from the stack was carried out in an old municipal solid waste incinerator (MSWI) from Montcada (Barcelona, Spain). The main goal of the present study was to determine if the environmental PCDD/F levels in the area under direct influence of the facility were mainly due to PCDD/F emissions from the plant. For this purpose, soil and herbage samples were collected near the MSWI before (1998) and after (2000) the technical improvements were performed. PCDD/F congener profiles were determined and compared with those from samples collected in a suburban area of Constantí (Tarragona, Spain) outside of direct emissions from any MSWI. The results of the present study suggest that the MSWI here assessed is not the main responsible for the environmental PCDD/F concentrations in the area under evaluation. Other PCDD/F emission sources in the same area seem also to have a notable impact on the atmospheric levels of these pollutants.     

Forest fire emissions in Portugal: a contribution to global warming?

A forecast of expected evolution of carbon dioxide (CO(2)) emissions in Portugal between 1988 and 2010 is presented. Predictions show that CO(2) emissions will almost double in the next twenty years. The equivalent potential CO(2) emissions from nitrogen oxides (NO(x)) and volatile organic compounds (VOC), for a time horizon of 20 years, is also presented. NO(x) and VOC emissions seem to make a significant contribution to the global warming potential of Portuguese emissions. Estimates of CO(2) emissions due to forest fires have been made, oriented towards the study of the Portuguese contribution to the global warming. If the burned area exceeds 100 000 ha this contribution could reach 7% of the total Portuguese CO(2) emissions. The global warming potential of Portuguese forest emissions were also calculated. The climate change predicted to Portugal could be responsible for an increase in the forest fires and consequently for a greater contribution of its emissions to the total values. It was concluded that it is important to quantify emissions of the greenhouse gases, including the contribution of forest fire emissions, not only in Portugal, but in all the Southern European countries.     

Portuguese inventory of dioxins and furans atmospheric emissions

This article presents the results of the most recent estimation of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) atmospheric emissions in Portugal, which has covered the period 2004–2009 and includes 27 emission sources types. The results are compared with previous emissions inventories published for Portugal. The main objective of this work is to provide relevant information about the amounts of the compounds that are released into the atmosphere in Portugal, and identify their major sources and trends.     

中国总量控制实践与发展态势

文中所说“总量控制”,全称是污染物排放总量控制制度。当污染物超出环境容量,总量控制一般以削减现有总量的方式出现,也就是通常所说的“减排”。结构减排在减排中占据主导的核心地位。实践表明,“节能必减排,减排促节能”。节能减排相结合是推动经济发展方式转变、调整经济结构、提高自主创新能力、实现环境与发展“双赢”的一种有效途径,也是科学发展的必然要求。节能减排与应对气候变化密不可分,是应对气候变化的主要支撑面。控制温室气体（以CO2为代表）排放强度,是对污染物排放总量控制制度的深化与发展。     

Diagnostic study of critical circuits of the Kraft pulp production process considering the environmental aspects

This paper describes systematic work undertaken in the field of atmospheric emissions from Portuguese Kraft pulp mills. The study led to the determination of emission factors from stationary sources, which proved to be an important tool for assessing the need for investment in air pollution abatement equipment, specifically for malodorous gases.     

Modeling the atmospheric transport and deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans in North America

The atmospheric fate of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was simulated for the year 2000 in North America using a SMOKE/CMAQ-based chemical transport model that was modified for this purpose. The 1999 USEPA emission inventories of PCDD/Fs and criteria pollutants were used. The 1995 Canadian emission inventory of criteria pollutants and the 1995 Canadian area source emissions for PCDD/Fs were used with the 2000 Canadian point source emissions. Modifications to CMAQ involved coupling it with dual organic matter (OM) absorption and black carbon (BC) adsorption models to calculate PCDD/F gas–particle partitioning. The model satisfactorily reproduced the particle bound fractions at all rural sites for which there were measured data and across the whole domain, the modeled vs. measured differences in particle bound fractions were less than 20% for nearly all congeners. The model predicted ambient air PCDD/F concentrations were also consistent with measurements. Simulated deposition fluxes were within 58% of direct measurements. PCDD/F atmospheric depositions to each of the Great Lakes were estimated for the year 2000. The results indicate that approximately 76% of the total deposition of PCDD/Fs to the Great Lakes (in W-TEQ, or toxic equivalent units as defined by the World Health Organization) is attributed to PCDD/Fs absorbed into OM in aerosol. For all of the lakes, more than 92% of all deposition is particle phase wet deposition and only 5–8% is particle phase dry deposition. Wet deposition from the gas phase is negligible. Of the 17 toxic PCDD/F congeners, the Cl_4–5DD/F compounds contribute approximately 70% to the total atmospheric deposition to the Great Lakes. The seasonal changes in the PCDD/F deposition flux track variations in ambient temperature.     

Diagnostic Study of Critical Circuits of the Kraft Pulp Production Process Considering the Environmental Aspects

Abstract

This paper describes systematic work undertaken in the field of atmospheric emissions from Portuguese Kraft pulp mills. The study led to the determination of emission factors from stationary sources, which proved to be an important tool for assessing the need for investment in air pollution abatement equipment, specifically for malodorous gases.     

Estimation of heavy metal emission fluxes on the territory of the NIS

As the result of our research, the specific procedures to use emission factor methodology were developed and applied for trace metal emission evaluation into the atmosphere over the territory of the former Soviet Union. The existing data on heavy metal emissions were revised as background information from official sources and expert estimations. Source categories and different initial information as well as the concept of spatial emission distribution were defined and observed. The calculated atmospheric emissions of lead, cadmium and mercury were produced among the main source categories of 12 NIS countries for 1990, 1995 and 1997, using modified emission coefficients.Total cadmium emissions into the atmosphere from determined source categories were estimated as 388.4 tonnes in 1990 for the whole domain with reduction by up to 207.0 tonnes per year for 1997. Mercury emissions were estimated as equal to 303.2 tonnes in 1990 and 159.8 tonnes in 1997. Lead emission amounted to 24903.0 tonnes in 1990, and 9652.5 tonnes in 1997.The results of the evaluation demonstrated the general trends of atmospheric heavy metal emissions with a greater decrease during the first half of the 1990s followed later by the rather stable level to be explained by recession in industrial activity and fuel consumption in NIS in that period. The significant spatial variations of atmospheric emissions over vast territories are described based on the results of their distribution according to 1×1 degree grid with remarkably higher values in the location of industrial cities.     

Primary emissions of fine carbonaceous particles in Europe

The European emissions of BC and OC in fine particles are calculated for the years 1990, 1995 and 2000 applying the RAINS model that, beyond fuel-sector distinction, explicitly includes various combustion technologies and the penetration of abatement options. The emission factors used are developed considering specific European conditions. The main sources of carbonaceous aerosols in Europe are emissions from traffic and residential combustion of solid fuels. Between 1990 and 2000, the BC and OC emissions are estimated to decline from 0.89 to 0.68 Tg and from 1.4 to 1.0 Tg, respectively. Most of the reduction occurred in the early 1990s in Eastern Europe owing to structural changes that resulted in energy efficiency improvements in industry and lower consumption of solid fuels in residential–commercial sector; the latter having strong impact on BC and OC emissions. Furthermore, the growth in transport volumes, and expected increase in emissions, was offset by introduction of stricter legislation for road transport from 1995. Focusing on the most important sectors, transport and residential combustion, the variation in measured carbonaceous emission shares and its impact on total emissions was evaluated. This analysis indicates a range of about −25% to +20% for BC and −7% and +15% for OC, compared to the central case.     

Derivation of new emission factors for quantification of mass emissions when using optical gas imaging for detecting leaks

This paper describes the development of new "leak/no-leak" emission factors that are suitable for estimating facilities' fugitive emissions when using an alternative work practice (AWP) that is based on optical gas imaging technology for detecting leaking piping system components. These emission factors were derived for valves, pumps, and connectors/flanges for instrument leak detection thresholds ranging from 3 to 60 g/hr using a combination of field data and Monte Carlo statistical simulation techniques. These newly derived leak/no-leak emission factors are designed to replace the U.S. Environment Protection Agency (EPA) 1995 Protocol factors, which were based on Method 21 monitoring of leaks at "uncontrolled" facilities. The emission factors published in the 1995 Protocol have not been updated since the 1970s. This derivation is based on results where the authors document the use of a Monte Carlo simulation technique to quantify the required leak detection thresholds that provide equal--or better--environmental benefits for an AWP. The use of these newly derived emission factors is demonstrated for different methods of computing fugitive emissions from a hypothetical model refinery. The resulting facility emissions calculated by using these new emission factors is compared with the existing emission estimation methods provided in the EPA 1995 Protocol. The results demonstrate that the new emission factors provide an emission estimate that is the closest to that obtained from the direct determination of total emissions by Monte Carlo simulations.     

Spatial surrogates for the disaggregation of CORINAIR emission inventories

CORINAIR atmospheric emission inventories are frequently used input data for air quality models with a domain situated in Europe. In CORINAIR emission inventories, sources are broken down over 11 major source categories. This paper presents spatial surrogates for the disaggregation of CORINAIR atmospheric emission inventories for input of air pollutants and particulate matter to grid or polygon based air quality model domains inside Europe. The basis for the disaggregation model was the CLC2000 land cover data to which statistical weights were added. Weights were population census data for residential emissions, employment statistics for agricultural and industrial area emissions, livestock statistics for ammonia emissions and annual aircraft movements for emissions realized by air transport. Additional road and off-road network information was used to disaggregate emissions realized by traffic. A comparison of top down produced emission estimates with spatially resolved national emission data for The Netherlands and the United Kingdom gave confidence in the present spatial surrogates as a tool for the top down production of atmospheric emission maps. Explained variance at a spatial resolution of 5 km was >70% for CO, NMVOC and NO_x, >60% for PM10 and almost 50% for SO₂.     

2010—2019年成都市机动车排污特征分析及防控措施减排效果评估

为评估2010—2019年成都市机动车防控措施的减排效果,以2010年为基准年,采用排放清单法计算了各减排措施下2019年的减排量,对比分析了4种控制措施的减排效益。结果表明：成都市机动车排污总量逐年下降,2019年PM_2.5、NO_x、VOCs、CO、SO₂和NH₃的排放量分别为0.27×10⁴、4.63×10⁴、1.70×10⁴、28.99×10⁴、0.21×10⁴和0.45×10⁴ t,主要分布在中心城区,其中重型货车对PM_2.5和NO_x贡献最大,小型客车对VOCs、CO、SO₂和NH₃贡献最大;措施中加严标准的综合减排量最大,重点减排车型为小型客车、轻型货车、公交车等,2019年6种污染物减排量分别为0.14×10⁴、2.27×10⁴、1.29×10⁴、6.77×10⁴、0.07×10⁴和0.38×10⁴ t;优化城市交通管理对小型客车和摩托车的减排效果显著,2019年6种污染物减排量分别为0.04×10⁴、0.81×10⁴、0.38×10⁴、2.55×10⁴、0.05×10⁴和0.04×10⁴ t;淘汰高排放车辆对小型客车、轻型货车等的减排较明显,2019年6种污染物减排放量分别为0.13×10⁴、0.98×10⁴、0.34×10⁴、2.62×10⁴、0.01×10⁴和0.007×10⁴ t;推广清洁能源汽车的重点减排车型为出租车和公交车,虽然可有效减少PM_2.5、NO_x的排放,但VOCs却有小幅增加,2019年6种污染物减排放量分别为0.12×10⁴、0.62×10⁴、−0.13×10⁴、0.30×10⁴、0.004×10⁴和0.000 5×10⁴ t。     

Evaluation of the Effects of Emission Reductions on Secondary Particulate Matter in the South Coast Air Basin of California

An Aerosol Trajectory Model (ATM) is applied to the South Coast Air Basin of California for a two-day episode in August 1982 to evaluate proposed control strategies that aim to reduce atmospheric aerosols. Model predictions Indicate that secondary organic aerosols decrease linearly with reactive hydrocarbon emissions. In addition, the model shows that If sulf ate is produced only in the gas phase by oxidation of SO₂, then reduction In SO₂ emissions yields a nearly proportional decrease In sulfate levels. Reduction in ammonia emissions, combined with reduction of NO_x emissions, gives the best results In terms of nitrate control. The order in which the emission controls are implemented Is predicted to have a major impact on the reduction of secondary atmospheric aerosols.     

A Method for Rapid Calculation of Merchant Vessel Combustion Emission

A simple method for calculating long term (1 year average) combustion emissions from cargo vessels is presented. The method uses emission factors for the five EPA criteria pollutants based on the amount and type of cargo carried by these vessels. Separate emission factors are derived for the underway and docking operations based on current fuel consumption to transport or load/unload cargo. Fuel consumption is then converted to emission factors in the form of tons of pollutant per million ton miles of cargo transported or tons of pollutant per million tons of cargo loaded/unloaded. The emission calculations can be performed on a desk calculator using data published in a federal document. The annual emissions of the Port of Houston are estimated as a sample calculation. The report also Includes a method of determining the spatial distributions of the emissions and a listing of stack parameters.