Search results for "Environmental engineering"
showing 10 items of 2674 documents
Wastewater modification processes in a stabilization reservoir: a new mathematical model
2018
The paper presents a mathematical model for the simulation of the ecology of a wastewater stabilization reservoir (WSR). WSRs are hypertrophic aquatic systems devoted to water storage in warm countries where shortage conditions are often encountered. Several factors that affect the stabilization reservoir’s effluent quality were taken into account: hydraulics and hydrology, solar radiation, reaeration, algae, zooplankton, organic matter, pathogens, and sediment-water interactions. The model quantifies the specific influence of each factor on effluent quality, and evaluating the correlation between the different factors. State variables included in the model were: algae, dissolved oxygen, or…
The Influence of Biomass Ash on the Migration of Heavy Metals in the Flooded Soil Profile - Model Experiment
2014
Soils that have been exposed to fl ood waters can be heavily polluted by inorganic and organic compounds. They are mainly compounds which appear in dissolved or suspended form fl owing together with heavily laden fl oodwater, as well as compounds created as a result of reactions in the soil profi le, mostly due to anaerobic transformation of organic matter. Heavy metals brought with fl ood waters are absorbed by the soil and also washed out from fl ood sediments by precipitation when the fl ood recedes. This paper presents the results of research on the effects of fertilization with ash from incineration or pyrolysis of biomass on the migration process of heavy metals (Zn, Cu, Cr, Ni, Pb, C…
Evaluation of a pilot-scale biotrickling filter as a VOC control technology for the plastic coating sector
2011
Abstract The performance and feasibility of a biotrickling filter (BTF) pilot unit for the treatment of exhaust gases from two robotic spray paint booths at a plastic coating facility were investigated. The volatile organic compound (VOC) concentrations in the emissions of the exhaust gases from the paint booths were relatively stable, although the VOC composition depended on the applied solvent-paint formulation in the booths. The pilot plant was operated for one year at empty bed residence times (EBRTs) ranging from 30 to 93 s. The performance of the system was affected by the solvent-paint formulations. An EBRT between 30 and 40 s was enough to meet legal requirements for products contai…
Use of biological and sedimentation models for designing Peñíscola WWTP.
2004
This paper presents Peñíscola wastewater treatment plant design. Peñíscola is a tourist city in Castellón (Spain), whose population changes significantly between summer and the rest of the year. The design of the biological and settling treatment units has been confirmed by computer model simulations and provided for biological organic matter, nitrogen and phosphorus removal. Two different treatment schemes have been proposed in order to optimize the plant performance during both seasonal operations. During low-load season, the plant will be operated under extended aeration conditions, so further sludge stabilization will not be needed. During high-load season, the plant will be operated un…
Mercury Speciation in Floodplain Soils and Sediments along a Contaminated River Transect
1998
A novel mercury-specific sequential extraction procedure (SEP) for the assessment of mercury (Hg) speciation in soils and sediments, with emphasis on studying the interaction between Hg and organic matter (OM), was developed and tested. It was applied to determine Hg speciation in floodplain topsoils and surface sediments along the Hg-contaminated part of the river Elbe, and to simultaneously derive some information on the (re)mobilization potentials for Hg from these matrices. The majority of the total Hg in the ecosystem today is bound in the floodplains, which also still geographically reflect the historic emission record. Most of the Hg in both matrices is bound strongly to OM, suggesti…
Distribution of volatile organic compounds in Sicilian groundwaters analysed by head space-solid phase micro extraction coupled with gas chromatograp…
2008
This work presents the results of an assessment of the existence and concentration of 13 volatile organic compounds (VOCs) in groundwaters from 14 hydrological basins in Sicily (25,710km (2)). On the basis of hydrological, hydrogeochemical and geological studies, 324 sampling points were selected. All groundwater sampled were collected twice, from October to December 2004 and from February to May 2005, and were analysed to determine the concentration and spatial distribution of the VOCs in the aquifers. The need to analyze a large number of samples in a short space of time so as to obtain quantitative analyses in trace concentration levels spurred us to create a new analytical method, both …
Energy and environmental impact of an anaerobic membrane bioreactor (AnMBR) demonstration plant treating urban wastewater
2020
Abstract In order to assess the environmental feasibility of anaerobic membrane bioreactor (AnMBR) technology for urban wastewater (UWW) treatment at ambient temperature, a demonstration plant was operated within the LIFE MEMORY project ( http://www.life-memory.eu/en/ ). This plant incorporates full-scale hollow-fiber membrane modules and was fed with the effluent from the pre-treatment of the “Alcazar de San Juan” WWTP (Alcazar de San Juan, Ciudad Real, Spain). Because of the dimensions of this plant, the system can be regarded as a previous step to the scale-up of AnMBR technology for full-scale UWW treatment. High-energy recovery potentials were achieved treating medium-/high-loaded UWW …
Changes in Climate and Land Use Over the Amazon Region: Current and Future Variability and Trends
2018
This paper shows recent progress in our understanding of climate variability and trends in the Amazon region, and how these interact with land use change. The review includes an overview of up-to-date information on climate and hydrological variability, and on warming trends in Amazonia, which reached 0.6-0.7 °C over the last 40 years, with 2016 as the warmest year since at least 1950 (0.9 °C +0.3°C). We focus on local and remote drivers of climate variability and change. We review the impacts of these drivers on the length of dry season, the role of the forest in climate and carbon cycles, the resilience of the forest, the risk of fires and biomass burning, and the potential “die back” of …
BIOMASS UTILIZATION AS A RENEVABLE ENERGY SOURCE IN POLISH POWER INDUSTRY – CURRENT STATUS AND PERSPECTIVES
2015
The depletion of the conventional energy sources, as well as the degradation and pollution of the environment by the exploitation of fossil fuels caused the development of renewable energy sources (RES), including biomass. In Poland, biomass is the most popular renewable energy source, which is closely related to the obligations associated with the membership in the EU. Biomass is the oldest renewable energy source, and its potential, diversity and polymorphism place it over other sources. Besides, the improvement in its parameters, including an increase in its calorific value, resulted in increasing use of biomass as energy source. In the electric power industry biomass is applied in the p…
Collectivités et prestataires de services : enquête exploratoire pour la collecte des déchets ménagers
2006
Private management of local waste has been scarcely studied although this question shows an original technico-institutionnal pattern in the field of local urban management. Under the rule of the “Code des marchés publics”, arrangements are made on a pluriannual basis. Such a legal framework is supposed to imply competitive procedure and thus to strengthen the decision making process of local authorities. Yet, the actual control of public authorities over this relationship is put under question. This article – based on a number of empirical studies — deals with this matter. It reveals what is at stake by studying closely the actual process of a contract between a local authority and a firm.