Characterisation of non-condensable sulphur containing gases from Kraft pulp mills

This paper describes work performed on the sampling and analysis of non-condensable gases (NCG) emitted from diffuse sources of a Portuguese Kraft pulp mill, which is the background information for a NCG collection, treatment and disposal system. The variability found in the composition of the gaseous compounds showed the existence of gaseous streams other than typical total reduced sulphur (TRS) compounds as usually described. From the measured TRS concentrations and the gas flow rate from each source it was possible to calculate the emission flow rate, E, of each source. These emission flow rates were then divided into three categories which are quite useful to identify significant sources and to choose abatement techniques. The methodology presented allows for a precise quantification of sources so that similar emissions can be grouped for treatment purposes. Sources with an emission flow rate bigger than 1 kg/h have a marked effect on the overall TRS emissions of the mill, as they are major contributors. It was also found that a new analytical procedure using Restek columns is more easy to use and overcomes operational problems noticed previously, namely a run time of 20-25 min instead of 50-60 min.     

Degradation of reactive dyes I. A comparative study of ozonation, enzymatic and photochemical processes

The environmental problems associated with textile activities are represented mainly by the extensive use of organic dyes. A great number of these compounds are recalcitrant and shown carcinogenic or mutagenic character. In this work three processes were studied for degradation of an anthraquinone dye (C.I. reactive blue-19). The ozonation process leads to complete decolorization with a very short reaction time; however, effective mineralization of the dye was not observed. The enzymatic process promotes quick decolorization of the dye; nevertheless, maximum decolorization degrees of about 30% are insignificant in relation to the decolorization degree achieved by the other processes. The best results were found for the photocatalytical process. The use of ZnO or TiO2 as photocatalysts, permits total decolorization and mineralization of the dye with reaction times of about 60 min.     

A gas chromatography-quartz crystal microbalance for speciation of sulfur compounds in landfill gas

A new method, based on separation with gas chromatography and detection with a quartz crystal microbalance, was used for the quantification of ethane-1-thiol, propane-1-thiol, ethyl methyl sulfide, propane-2-thiol, butane-2-thiol and butane-1-thiol. The analytical error, the analysis time and the general analytical performance are identical for gas chromatography-mass spectrometry (GC-MS) and gas chromatography-quartz crystal microbalance (GC-QCM). However, the GC-QCM method constitutes a low cost alternative to GC-MS for monitoring individual sulfur compounds in landfill gas. It is an easily assembled apparatus made with an injection device, a furnace, a column, a crystal cell and a quartz crystal.     

Atmospheric baseline levels of PCDD and PCDF in the region of Oporto

An external monitoring plan (EMP) is being implemented in the region of Oporto, Portugal, to follow the potential effects of a future incinerator of municipal solid waste. Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF) were measured during 1998 and the first semester of 1999, prior to the working up of the incineration unit. The baseline levels obtained through this intensive monitoring work are presented and discussed in the present paper.     

对加拿大东南部湖泊从酸沉降效应中恢复的评价

北美洲SO2排放量的减少激起了人们对加拿大东南部的水生态系统能迅速摆脱酸化的状态的期待.但是只有那些明显减少了排放量的冶炼厂附近的湖泊达到了这种期望值.在临近大西洋的省份魁北克和安大略,受远程污染源影响的湖泊的硫酸根离子(SO2- 4)浓度都有一定降低,但pH和碱度则仅有较少量的提高.对于这种延迟的酸度响应,有如下几种因素可以解释:碱基阳离子含量的下降,干旱加速SO2- 4的迁移,水体内部碱性物质生成机制遭到破坏;同时硝酸盐和有机阴离子含量的提高也可能是其中的原因.对加拿大东南部生物恢复的监测资料非常有限,即使有的话,在萨德伯里(Sudbury)和基拉尼(Killarney)地区以外也很难找到恢复的证据.比如,尽管除了酸化作用外其他因素也对上述现象有一定影响,新思科舍河中的大西洋鲑鱼出现率和安大略湖潜鸟的繁殖成功率实际上正在下降.化学和生物学模型预测,只有比目前法规要求严格的多的SO2排放削减额才能促进广泛的化学恢复和其后的生物恢复,而在加拿大东南部的众多湖泊中重建工业化前的化学与生物学条件或许很难实现.     

Correction to: Ecological restoration as a strategy for mitigating and adapting to climate change: lessons and challenges from Brazil

Mitigation and Adaptation Strategies for Global Change - The original version of the article unfortunately contained an error.     

Basis for a national strategy for integrated coastal zone management—in Portugal

This paper includes the proposals made in the report “Basis for a National Strategy for Coastal Zone Management” prepared for the Portuguese Ministry of Environment, Territorial Planning and Regional Development. The final version of that report was presented in June 2006. This paper describes a theme framework followed by a discussion of concepts. Nine Primary Principles, eight Principal Objectives, and 37 Strategic Options for an Integrated Coastal Zone Management are then presented. These Strategic Options are set hierarchically according to their sequential priority, identifying the dominant types of Associated Measures. The analysis of these arrives at a set of Structural Measures, which interlink and aggregate various actions and propose a new method of integrated management for the coastal zone, which includes the “Legal Basis of Coastal Zone”; the Organization System; the Action Plan and Monitoring.     

Health Survey Among People Living Near an Abandoned Mine. A Case Study: Jales Mine, Portugal

Campo de Jales is a village surrounding the abandoned Jales mine. The area is heavily contaminated with heavy metals and dusts from large tailings piles as result of centuries of mining operations. The aim of this study is to investigate potential health threats associated with site contamination. The population studied comprised two groups: people living in Campo de Jales (n = 229) and a control group – people living in Vilar de Macada (n = 234). Lead and cadmium exposure and symptoms survey were carried out.The results showed a significant higher levels of blood lead and cadmium between the Campo de Jales residents (lead: 9.5 microgr/dl versus 7.7 microgr/dl; cadmium: 0.84 microgr/dl versus 0,65 microgr/dl) as well as to a higher prevalence of respiratory and irritation symptoms and great concern about his own health.In conclusion: community is the scene of long-term health problems resulting from the site environmental contamination.     

Statistical analysis in estimating probable concentrations of representative chemical species in leachate: a solution for the source term of new or unmonitored landfills

Journal of Material Cycles and Waste Management - Leakage modeling can be crucial for environmental management and control of waste landfills. However, defining boundary conditions for these models...