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Pulp industry plays an important role in the structure of European economy and society. Paper pulp manufacture, the industrial utilization of plant biomass, is increasing every year. In Spain, Eucalyptus is the dominant raw material and the Kraft cooking and total chlorine free (TCF) bleaching processes lead the procedures of Eucalyptus paper pulp production. This paper aims to identify and quantify the environmental impacts associated to Eucalyptus TCF pulp manufacture by using Life Cycle Assessment (LCA) as an analytical tool. The system has been defined using a cradle-to-gate perspective, that is to say from forest activities to the exit gate of the pulp mill. The production of chemicals consumed in the cooking and bleaching stages as well as the on-site energy production system is the elements that contribute the most to all impact categories analyzed (more than 50% of total contributions), except for the eutrophication potential where forest activities and waste treatment play an important roles (about 52% of total). Specific actions associated to the recovery boiler, lime kiln and digestion stage could considerably reduce the environmental impact and improve the environmental performance of the Spanish paper pulp industry.  相似文献   
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In the present work, selected agroindustrial solid residues from Brazil – biosolids from meat processing wastewater treatment and mixture of sawdust with these biosolids; residues from apple and orange juice industries; sugarcane bagasse; açaí kernels (Euterpe oleracea) and rice husk – were characterised as solid fuels and an evaluation of their properties, including proximate and ultimate composition, energy content, thermal behaviour, composition and fusibility of the ashes was performed. The lower heating value of the biomasses ranged from 14.31 MJ kg?1 to 29.14 MJ kg?1, on a dry and ash free basis (daf), all presenting high volatile matter content, varying between 70.57 wt.% and 85.36 wt.% (daf) what improves the thermochemical conversion of the solids. The fouling and slagging tendency of the ashes was predicted based on the fuel ash composition and on the ash fusibility correlations proposed in the literature, which is important to the project and operation of biomass conversion systems. The potential for application of the Brazilian agroindustrial solid residues studied as alternative energy sources in thermochemical processes has been identified, especially concerning direct combustion for steam generation.  相似文献   
65.
Abstract: This paper assesses cost efficiencies of Brazilian public and private companies of water supply. To measure the efficiency, we used a stochastic frontier model derived from the translog family – a specification similar to a Cobb‐Douglas including a quadratic term in log output. The model parameters are estimated by maximum likelihood using Brazilian data for the year 2002. Statistical inference leads to the conclusion that there is no evidence that private firms and public firms are significantly different in terms of efficiency measurements.  相似文献   
66.
Environmental Science and Pollution Research - Ciprofloxacin (Cipro) water contamination is a global concern, having reached disturbing concentrations and threatening the aquatic ecosystems. We...  相似文献   
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Environmental Science and Pollution Research - The lignocellulose biorefinery industry has assumed an important role within the current scenario. Lignin is an abundant and available biopolymer and...  相似文献   
68.
Environment, Development and Sustainability - Tourists have become increasingly interested in certain aspects of their destination, including landscape and biodiversity elements, thereby promoting...  相似文献   
69.
Environmental Science and Pollution Research - The current study has assessed whether the oral and/or dermal exposure of C57Bl/6 J mice to tannery effluent (a complex pollutant consisting of...  相似文献   
70.
Some health important enteric viruses are considered to be emerging waterborne pathogens and so the improvement of detection of these viruses in the aquatic environment is one of the most important steps in dealing with these pathogens. Since these viruses may be present in low numbers in water, it is necessary to concentrate water samples before viral detection. Although there are several methods to concentrate viruses in environmental waters, all present some drawbacks and consequently the method should be chosen that, despite its limitations, is adequate to achieve the aim of each study. As the effectiveness of the concentration methods is evaluated by determining the efficiency of viral recovery after concentration, it is important to use a simple and effective approach to evaluate their recovery efficiency. In this work ultracentrifugation, usually used as a secondary step for virus concentration, was evaluated as the main method to concentrate directly viruses in environmental water samples, using the microscopic enumeration of virus-like particles (VLP) as a new approach to estimate the efficiency of recovery. As the flocculation method is currently employed to concentrate viruses in environmental waters, it was also used in this study to assess the efficiency of the ultracentrifugation as the main viral concentration method in environmental waters. The results of this study indicate that ultracentrifugation is an adequate approach to concentrate viruses directly from environmental waters (recovery percentages between 66 and 72% in wastewaters and between 66 and 76% in recreational waters) and that the determination of VLP by epifluorescence microscopy is a simple, fast and cheap alternative approach to determine the recovery efficiency of the viral concentration methods.  相似文献   
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