Search results for "Disposal"
showing 10 items of 1300 documents
Use of physicochemical processing in treating urban waste waters
1994
The principal objective of the present study was to compare two clearly defined purification processes in two stages: the periods 1985–1987 (conventional) and 1988–1990 (physico‐chemical). In general, the mean concentrations obtained were lower in the second period. A z‐test for comparing means was applied, but no significant correlation was observed (p ≤ 0.05). The mean concentrations obtained (with some exceptions) are lower in the second period. With the passing of time, the total volume of sewage flow has increased, and hence the load of contaminants has become diluted. The use of physico‐chemical treatment prior to biological processing may be the cause of the increase in cost.
Climate variability and agricultural production efficiency: evidence from Ethiopian farmers
2020
It is known that climate and weather variability have negative impacts on agricultural production efficiency. The aim of this study is to analyse the impact of climatic variables on farms’ efficiency in Ethiopia making use of nationally representative datasets from Living Standards Measurement Study–Integrated Surveys on Agriculture (LSMS-ISA) 2011/2012. By using the Stochastic Frontier Approach, we estimate simultaneously the farmers’ optimal production function and technical inefficiency equations, taking into account unobserved heterogeneity of farmers. Our main findings show that climate change variables have a positive effect on households’ efficiency but the impact depends on the diff…
Consumers' perceptions of sustainably produced food: a focus group study
2009
The purpose of this study is to provide information on consumers' perceptions of sustainably produced food products and the main product attributes that influence consumers' buying behaviour in the case of organic, Fair Trade and locally produced food. The paper draws on data from four focus groups. The results provide empirical insight into the motivating as well as the restricting factors that influence consumers' purchasing behaviour in the case of sustainably produced food and introduce the emerging key themes associated with the attributes of sustainably produced food products.
How does seasonality affect water reuse possibilities? An efficiency and cost analysis
2012
Abstract Because of the harsh conditions of water stress and seasonal water demand in many zones, water reuse has emerged as a key alternative for achieving sustainable water management. An efficient performance by wastewater treatment plants (WWTPs) in technical and economic terms favors water reuse. However, seasonality in the flow of wastewater and in the pollutant load may be a determining factor in the efficiency of WWTPs. To evaluate if seasonality affects WWTP efficiency, analytical benchmarking methodology Data Envelopment Analysis (DEA) is used to obtain an average efficiency score for seasonal and non-seasonal plants. Given the importance of extended aeration (EA) and activated sl…
Life cycle assessment of low temperature asphalt mixtures for road pavement surfaces: A comparative analysis
2018
The increasing fuel consumption demand, the accelerated pressure imposed by the depletion of 5 scarce raw materials and the urgent environmental protection requirements are forcing the change of 6 pavement industry and academia community’s research endeavors towards the development of low 7 emissions road paving technologies able to significantly reduce mixing and compaction temperature as 8 well as the consumption of virgin raw materials. One set of relatively recent technologies in the field of 9 pavement materials that aims at addressing those concerns are the warm mix asphalt (WMA). In fact, 10 they have the potential to allow the reduction of energy consumption and airborne emissions d…
Survey of organochlorines in Finnish watercourses by caged mussel method
2002
Monitoring organochlorine compounds with caged common lake mussels (Anodonta piscinalis) in the pulp and paper mill recipient watercourses of Finland annually from 1984 produced many statistically significant time trends. A decrease of chlorophenols and chloroguaiacols originating from chlorobleaching were observed in all recipients in parallel with the decreasing discharges from the mills. Metabolites of chlorophenols, chloroanisoles and chloroveratroles were constant. Significantly elevated PCB concentrations were measured in four watercourses. At two of these areas, the PCB concentrations were constant. In contrast, a statistically significant increase of PCB (and DDE) was found at one r…
Laboratory investigations on co-digestion of energy crops and crop residues with cow manure for methane production: Effect of crop to manure ratio
2007
Abstract Anaerobic co-digestion of grass silage, sugar beet tops and oat straw with cow manure was evaluated in semi-continuously fed laboratory continuously stirred tank reactors (CSTRs). Co-digestion of manure and crops was shown to be feasible with feedstock volatile solids (VS) containing up to 40% of crops. The highest specific methane yields of 268, 229 and 213 l CH4 kg−1 VSadded in co-digestion of cow manure with grass, sugar beet tops and straw, respectively, were obtained with 30% of crop in the feedstock, corresponding to 85–105% of the methane potential in the substrates as determined by batch assays. Including 30% of crop in the feedstock increased methane production per digeste…
Paradigms on landfill mining: From dump site scavenging to ecosystem services revitalization
2017
For the next century to come, one of the biggest challenges is to provide the mankind with relevant and sufficient resources. Recovery of secondary resources plays a significant role. Industrial processes developed to regain minerals for commodity production in a circular economy become ever more important in the European Union and worldwide. Landfill mining (LFM) constitutes an important technological toolset of processes that regain resources and redistribute them with an accompanying reduction of hazardous influence of environmental contamination and other threats for human health hidden in former dump sites and landfills. This review paper is devoted to LFM problems, historical developm…
A systematic assessment of road pavement sustainability through a review of rating tools
2017
Pavements are engineered systems present in every modern society, and they have significant environmental, economic and social impacts. In an effort to promote more sustainable decisions regarding pavement design, construction and management, several pavement sustainability assessment tools have been developed. This research reviewed some of these tools and found that many of them do not treat the pavement as a system; instead, they seek to optimize individual aspects of the pavement in an effort to increase its sustainability. Therefore, a framework for analytically assessing the system outcomes towards sustainable objectives is presented and applied for modern pavement sustainability asse…
Environmental impact of Recover cotton in textile industry
2017
A comparative evaluation of the life cycle assessment (LCA) of Recover cotton, obtained from recycled garments, and virgin one, cultivated from traditional and organic crops, has been made based on the quantification of environmental impact categories, such as abiotic depletion, global warming, water use, acidification and eutrophication potential. LCA data reported in the literature for the steps of cultivation, ginning/cutting, and dyeing were compared in order to clearly show the environmental advantages of moving from traditional practices, to organic cultivation and the use of Recover cotton, a novel procedure that involves the production of cotton yarns from coloured and well characte…