Chemical and physical characterization of emissions from birch wood combustion in a wood stove

The purpose of this study was to characterize the emissions of a large number of chemical compounds emitted from birch wood combustion in a wood stove. Birch wood is widely used as fuel in Swedish household appliances. The fuel load was held constant during six experiments.Particles <2.5 μm in diameter were collected and the size distribution of the particles was measured. The results were compared to the size distribution in road traffic emissions. It could be seen that the number distribution differed between the sources. In traffic exhaust, the number of particles maximized at 20 nm, while the number distribution from wood burning ranged from 20 to 300 nm. The ratio K/Ca on particles was found to be significantly different in wood burning compared to road dust, range 30–330 for the former and 0.8±0.15 for the latter. The source profile of common elements emitted from wood burning differed from that found on particles at a street-level site or in long-distance transported particles.The ratio toluene/benzene in this study was found to be in the range 0.2–0.7, which is much lower than the ratio 3.6±0.5 in traffic exhaust emissions.Formaldehyde and acetone were the most abundant compounds among the volatile ketones and aldehydes. The emission factor varied between 180–710 mg/kg wood for formaldehyde and 5–1300 mg/kg wood for acetone. Of the organic acids analyzed (3,4,5)-trimethoxy benzoic acid was the most abundant compound. Of the PAHs reported, fluorene, phenanthrene, anthracene, fluoranthene and pyrene contribute to more than 70% of the mass of PAH. Of the elements analyzed, K and Si were the most abundant elements, having emission factors of 27 and 9 mg/kg wood, respectively.Although fluoranthene has a toxic equivalence factor of 5% of benzo(a)pyrene (B(a)P), it can be seen that the toxic potency of fluoranthene in wood burning emissions is of the same size as B(a)P. This indicates that the relative carcinogenic potency contribution of fluoranthene in wood smoke would be about 40% of B(a)P.     

国外最佳管理措施在农业非点源污染防治中的应用

概述了国外最佳管理措施(BMPs)在农业非点源污染防治中的应用现状,工程措施有人工湿地、植被缓冲区和水陆交错带;管理措施有测土施肥、变量施肥、免耕-少耕法和生物篱等,以及它们所取得的成果,并展望其在国外和国内的发展趋势和前景.     

室内电磁辐射污染与防护

基于电磁辐射污染对环境和人体健康的影响 ,探讨了目前室内电磁辐射污染的现状和室内潜在的电磁辐射污染源 ,并就室内电磁辐射污染的防护措施提出了几点建议     

面源污染管理中不同类型工程设施的性能比较

为深入了解面源污染管理中不同类型工程设施的性能,本文对人工湿地、草生水路、植被过滤带、物理过滤池、渗滤沟及水力分离器的污染物去除效率及费用进行了评价。结果显示,不同类型工程设施对污染物质的去除能力不同。物理过滤池、人工湿地及渗滤沟在总体上表现出较高的污染物去除能力。而费用(包括建设费用和运行维护费用)比较发现,物理过滤池费用较高而人工湿地、植被过滤带及渗滤沟费用相对较低。较高费用的工程设施具有较高的污染物去除能力,如物理过滤池。而较低或中等费用的工程设施未必具有较低的污染物去除能力,如人工湿地。故在面源污染治理工程措施的选择中,应综合考虑不同设施的污染物质去除能力与建设及维护费用等指标。     

The impact of wood stove technology upgrades on indoor residential air quality

Fine particulate matter (PM_2.5) air pollution has been linked to adverse health impacts, and combustion sources including residential wood-burning may play an important role in some regions. Recent evidence suggests that indoor air quality may improve in homes where older, non-certified wood stoves are exchanged for lower emissions EPA-certified alternatives. As part of a wood stove exchange program in northern British Columbia, Canada, we sampled outdoor and indoor air at 15 homes during 6-day sampling sessions both before and after non-certified wood stoves were exchanged. During each sampling session two consecutive 3-day PM_2.5 samples were collected onto Teflon filters, which were weighed and analyzed for the wood smoke tracer levoglucosan. Residential PM_2.5 infiltration efficiencies (F_inf) were estimated from continuous light scattering measurements made with nephelometers, and estimates of F_inf were used to calculate the outdoor- and indoor-generated contributions to indoor air. There was not a consistent relationship between stove technology and outdoor or indoor concentrations of PM_2.5 or levoglucosan. Mean F_inf estimates were low and similar during pre- and post-exchange periods (0.32 ± 0.17 and 0.33 ± 0.17, respectively). Indoor sources contributed the majority (～65%) of the indoor PM_2.5 concentrations, independent of stove technology, although low indoor-outdoor levoglucosan ratios (median ≤ 0.19) and low indoor PM_2.5-levoglucosan correlations (r ≤ 0.19) suggested that wood smoke was not a major indoor PM_2.5 source in most of these homes. In summary, despite the potential for extensive wood stove exchange programs to reduce outdoor PM_2.5 concentrations in wood smoke-impacted communities, we did not find a consistent relationship between stove technology upgrades and indoor air quality improvements in homes where stoves were exchanged.     

一种水基燃烧新技术及其清除海洋油污应用

针对大面积海洋石油污染难以利用现有方法进行高效治理的问题,针对性地提出了一种简便实用的水基燃烧新技术,介绍了其技术特点和以碳化钙和金属钾为主要原料配方的化学反应原理,进而利用其独特的可长时间持续燃烧这一关键性能,设计开展了对海洋油污进行清除处理的实验研究。结果不仅表明了采用该技术处理海洋油污的有效性,特别是对实际最为常见且采用传统燃烧法根本无法处理的油层厚度不足3 mm的海洋原油污染,通过其对油层持续的点火和加热挥发等多种作用也可达到高效清除的目的,并从油层厚度与燃烧状况之间的关系对相关的理论问题进行了分析,体现了其良好的应用前景。     

基于最佳管理实践的中新生态城面源污染控制措施优选研究

基于最佳管理实践（BMP）理念和方法,以中新生态城为例,采用多属性决策分析方法的ELECTRE-Ⅲ方法和模型,采用VisualBasic语言自行编制辅助计算机程序,对该地区8种雨水控制管理措施进行了优化比选。优选结果表明,对于中新生态城,8种雨水控制管理措施的优选排序为：湿地〉地下蓄水库〉人渗沟〉可渗透路面砖〉道路边沟〉绿色屋顶〉下凹绿地〉绿化缓冲带。     

Indoor house pollution: Appliance emissions and indoor ambient concentrations

Emission rates for CO, NO, NO₂ and CH₂O from several unvented gas and kerosene heaters frequently employed in domestic heating have been measured. The indoor concentrations generated by these emissions are evaluated and compared to those determined in typical houses. It is found that both the predicted and measured values exceed the short term air quality standards accepted in most countries.     

Chemical and biological characterization of emissions from small residential stoves burning wood and charcoal

Emissions from a small residential wood stove and a newly developed residential stove burning charcoal have been characterized by chemical analysis and mutagenicity testing (Ames Salmonella test). For wood burning the samples were taken under normal and starved air conditions burning birch and spruce separately. The burning conditions in the stove seemed to influence the emissions to a larger extent than the type of wood.The emissions of aldehydes, benzene and polycyclic aromatic hydrocarbons from the charcoal-burning stove are lower by a factor of 25–1000 as compared to the wood stove. The mutagenicity of the emissions showed a similar trend.     

Indoor metallic pollution related to mining activity in the Bolivian Altiplano

The environmental pollution associated with mining and metallurgical activities reaches its greatest extent in several Andean cities and villages. Many locations in this area have accumulated through centuries a large amount of mining wastes, often disregarding the magnitude of this situation. However, in these naturally mineralized regions, there is little information available stating the exact role of mining and metallurgical industries in urban pollution. In this study, we demonstrated that the various metallic elements present in indoor dust (As, Cd, Cu, Pb, Sb, Sn, Zn) had a common origin and this contamination was increased by the proximity to the mines. Lead dust concentration was found at concerning levels for public health. In addition, wrong behaviors such as carrying mining workwear home contributed to this indoor dust pollution. Consequently, the constant exposure of the population could represent a potential health hazard for vulnerable groups, especially children.     

Lung-deposited dose of particulate matter from residential exposure to smoke from wood burning

Environmental Science and Pollution Research - Residential settings are of utmost importance for human exposure, as it is where people spend most of their time. Residential wood combustion is a...     

Non-destructive pollution exposure assessment by means of wood mice hair

Concentrations of cadmium, copper, lead and zinc were measured in hair, kidney, liver, lung and muscle tissue of wood mice captured along a pollution gradient. We found positive relationships between cadmium concentrations in hair and all internal tissues. Hair lead concentrations were positively correlated with lead contents in kidney and liver. Age had a significant effect on cadmium accumulation in all tissues and hair. Apart from a very weak relationship between zinc concentrations in hair and liver, no significant relation between copper or zinc content in hair and any of the internal organs was observed. In summary, our observations suggest that hair of wood mice can be used for monitoring exposure to non-essential metals like cadmium and lead, but not to homeostatically regulated metals such as copper or zinc.     

Cereal waste burning pollution observed in the town of Vitoria (northern Spain)

Agricultural waste burning is a widespread practice throughout the world but there is little information about its pollutant impact. This paper deals with a preliminary study of the pollution observed in Vitoria (Northern Spain) caused by cereal waste burning. The mean hourly flux of pollutants produced by cereal waste burning fires can reach values of 1.4 kt of CO₂, 13 t of TPM and 3 t of NO_x in the area around Vitoria. Measurements obtained in the area of emission and inside fire plumes show high ratios (NO₂/NO_x) indicating that nitrogen oxides emitted by the source undergo a rapid transformation in the same area of emission. Results relating to aerosol composition collected in Vitoria during burning periods show an increase in the concentration of K⁺, NO₃⁻ and Cl⁻ ions, that are inter-correlated. The modification of the ionic composition of aerosols also affects the chemistry of the rain collected in Vitoria. During the burning period, it is particularly noticeable that anthropogenic pollution (usually identifiable by the correlation between SO₄²⁻ and NO₃⁻ concentrations) disappears, indicating the existence of an independent source of NO₃⁻ not linked to the SO₄²⁻ source. Similar results were deduced studying BAPMON data collected in Spain during cereal waste burning. Finally, we note that ozone concentration measured at Vitoria is not affected by the pollution generated by the burning fires.     

The air pollution caused by the burning of fireworks during the lantern festival in Beijing

The effects of the burning of fireworks on air quality in Beijing was firstly assessed from the ambient concentrations of various air pollutants (SO₂, NO₂, PM_2.5, PM₁₀ and chemical components in the particles) during the lantern festival in 2006. Eighteen ions, 20 elements, and black carbon were measured in PM_2.5 and PM₁₀, and the levels of organic carbon could be well estimated from the concentrations of dicarboxylic acids. Primary components of Ba, K, Sr, Cl⁻, Pb, Mg and secondary components of C₅H₆O₄²⁻, C₃H₂O₄²⁻, C₂O₄²⁻, C₄H₄O₄²⁻, SO₄²⁻, NO₃⁻ were over five times higher in the lantern days than in the normal days. The firework particles were acidic and of inorganic matter mostly with less amounts of secondary components. Primary aerosols from the burning of fireworks were mainly in the fine mode, while secondary formation of acidic anions mainly took place on the coarse particles. Nitrate was mainly formed through homogeneous gas-phase reactions of NO₂, while sulfate was largely from heterogeneous catalytic transformations of SO₂. Fe could catalyze the formation of nitrate through the reaction of α-Fe₂O₃ with HNO₃, while in the formation of sulfate, Fe is not only the catalyst, but also the oxidant. A simple method using the concentration of potassium and a modified method using the ratio of Mg/Al have been developed to quantify the source contribution of fireworks. It was found that over 90% of the total mineral aerosol and 98% of Pb, 43% of total carbon, 28% of Zn, 8% of NO₃⁻, and 3% of SO₄²⁻ in PM_2.5 were from the emissions of fireworks on the lantern night.     

Temporal variation and impact of wood smoke pollution on a residential area in southern Germany

This paper is a continuation of our previous publication (Bari, M.A., Baumbach, G., Kuch, B., Scheffknecht, G., 2009. Wood smoke as a source of particle-phase organic compounds in residential areas. Atmospheric Environment 43, 4722–4732) and describes a detailed characterisation of different particle-phase wood smoke tracer compounds in order to find out the impact of wood-fired heating on ambient PM₁₀ pollution in a residential area near Stuttgart in southern Germany. The results from previous flue gas measurements help distinguishing different tracer compounds in ambient PM₁₀ samples. In the residential area, significant amounts of hardwood markers (syringaldehyde, acetosyringone, propionylsyringol, sinapylaldehyde) and low concentrations of softwood markers (vanillin, acetovanillone, coniferyldehyde, dehydroabietic acid, retene) were found in the ambient air. The general wood combustion markers Levoglucosan, mannosan and galactosan were detected in high concentrations in all particle-phase PM₁₀ samples. To find out the size distribution of ambient particles, cascade impactor measurements were carried out. It was found that more than 70% of particulate matter was in the particle diameter of less than 1 μm. Using emission ratio of levoglucosan to PM₁₀, it can be demonstrated that during winter months 59% of ambient PM₁₀ pollution could be attributed to residential wood-fired heating.     

Revisiting e-waste management practices in selected African countries

ABSTRACT

African countries are among the prime destinations of electronic waste (e-waste) also called Waste of Electrical and Electronic Equipment (WEEE), and have been challenged with the management of its environmental and health impacts. This paper was carried out to understand the e-waste sector and policy responses in selected African countries. Data for the study were generated from sources; such as policy documents, legislations and literature. Findings show that the import of WEEE is on rising in Africa while landfill and incineration continued to be widely used handling approaches. Countries studied lack WEEE specific national policies and stringent policy instruments to enforce proper collection and recycling systems. Despite the start-ups in emerging recycling operations, a major gap is that informal e-waste actors dominate the e-waste chain from collection to material extraction and refurbish activities through rudimentary tools that cannot detect toxic elements. Tackling the problem demands integrated multi-actor interventions with multiple stakeholders to reduce WEEE inflow on one hand, and ramping up safe recycling capacity on the other hand.     

Insights of healthcare waste management practices in Vietnam

Environmental Science and Pollution Research - Nowadays, together with the economic development, public health activities have gained substantial attention with increasing number of hospitals...     

An overview of environmental pollution prevention and management in China

This paper provides a broad overview of pollution prevention and management in China and details the specific measures that have been adopted at a national level. The paper begins by exploring some of the key environmental issues faced by China, and the history of environmental management in China. Then the current environmental legislation and standards in China are detailed, and the strategic pollution prevention measures that have been adopted are described. Next, the paper examines the environmental economic instruments and ethos that China appears to have adopted, and concludes by drawing a comparison with the development of pollution prevention in the western world and proposes a broad research agenda.