Laboratory-scale anaerobic sequencing batch reactor for treatment of stillage from fruit distillation

This work describes batch anaerobic digestion tests carried out on stillages, the residue of the distillation process on fruit, in order to contribute to the setting of design parameters for a planned plant. The experimental apparatus was characterized by 3 reactors, each with a useful volume of 5 L. The different phases of the work carried out were: determining the basic components of the Chemical Oxygen Demand (COD) of the stillages; determining the specific production of biogas; and estimating the rapidly biodegradable COD contained in the stillages. In particular, the main goal of the anaerobic digestion tests on stillages was to measure the parameters of Specific Gas Production (SGP) and Gas Production Rate (GPR) in reactors in which stillages were being digested using ASBR (Anaerobic Sequencing Batch Reactor) technology. Runs were developed with increasing concentrations of the feed. The optimal loads for obtaining the maximum SGP and GPR values were 8\u20139 gCOD L-1 and 0.9 gCOD g-1VS

Critical analysis of strategies for PM reduction in urban areas

This paper presents an overview of practical strategies that can be adopted for reducing the particulate matter concentration in urban areas. Each strategy is analyzed taking into account the latest results of the scientific literature. A discussion useful for pointing out some problems to be solved for their correct adoptions completes the paper

Aeraulic behaviour of a biotrickling filter pilot plant: experiments and simulations

Trickling bed biofilters (or biotrickling filters, BTFs) are biological systems for polluted air treatment. Hydrodynamics of BTFs, and reactors in general, is of paramount importance for obtaining good performances. In fact, a non-uniform distribution of the pollutant into the bed brings to dead zones or bypass which reduce the bed working volume and, therefore, cause low removal efficiencies. The paper presents the preliminary results obtained regarding the aeraulic behavior of a BTF pilot plant with seashells as packing material. Experimental results of bed void fraction and pressure drop at several flow rates were used to obtain Ergun equation coefficients for dry bed. A numerical simulation of the reactor flow field carried out with a commercial CFD (Computational Fluid Dynamics) code, validated by the means of velocity measurements made with a Hot Wire Anemometer (HWA) completed the analysis of the reactor hydrodynamics

Modeling for use of water in agriculture

The present paper examines and evaluates the results of a survey carried out to define the criteria for restoring the surface water of the karstic stream "Gravina" (Southern-Italy). The stream runs through a watershed including several agricultural areas. The stream shows an environmental heterogeneity which is of great value to the conservation of biodiversity. The analysis supports a more general water pollution control strategy aimed at safeguarding natural water quality in the urbanized watershed with the aim, also, to reuse partially the water in agriculture. The methodology was based on the surface water sampling, quality parameter analysis and simulation by modelling. The variation and compatibility of wastewater discharge and water stream quality were verified by using a model available in literature in function of biodegradable pollutant load and dissolved oxygen. Several scenarios based on the fixed yield of treatment plants were examined

The Use of Renewable and Alternative Fuel in the Heavy Clay Industry

Abstract The heavy clay industry brick is in many countries a very important economic factor with far reaching financial and environmental impacts. In the industrialized countries the use of alternative fuels in the heavy clay industry is rather limited.The European brick industries common current research activity is mainly focused on synthgas from waste streams. In-house research activity by single brick companies does, at least in Europe, not take place at the moment. The situation in the developing and industrializing countries is far different: The use of alternative,fossil and renewable, fuels in these countries is still wide spread. The use of such fuels does sometimes have severe negative impacts on the environment. This paper gives an overview of the use of various renewable and alternative fuels in the heavy clay industry in several countries and the environmental and financial impacts these fuels have or might have on the operation of a typical installation in various parts of the world (Maghreb, Europe, USA, Australia,India, Vietnam). Two examples in which alternative fuels have been or are used, one in an industrializing and one in an industrialized country, are briefly presented. A comparative product life cycle analysis, LCA, is presented

PCDD/F Emissions From Virgin And Treated Wood Combustion

Energy from biomass is becoming increasingly important as fossil fuel reserves diminish. The utilization of biomass is already prevalent in the domestic heating sector, but produces significant amounts of pollutants that are detrimental to human health. Dioxins, formed in any combustion process where carbon, oxygen and, chlorine are present, are a subject of major interest due to their carcinogenicity. Much research has been carried out to study emissions from hazardous and municipal waste incinerators. Dioxin emission from wood combustion plants are also of interest, especially those due to combustion of treated, varnished or PVC-coated wood, which can produce high polychlorinated dibenzofurans (PCDD/F) emissions. This study compares the PCDD/F emissions produced by burning treated wood and virgin wood to verify if the differences are significant. Six different wood samples were analysed (three of treated wood and three of virgin wood) and a two-step wood gasification boiler was used. The analysis has been conducted both on off gas and on ashes. The measured PCDD/F concentrations are to be considered particularly limited and the treated wood use does not cause a general worsening in the PCDD/F emission. Thus, the wood treatment – subject of study – is not dangerous for PCDD/F. Finally, the experimental results indicated that during the thermal treatment, the formation mechanism of PCDD/F is the de novo synthesis

Innovative Biogas Multi-Stage Biogas Plant and Novel Analytical System

AbstractThe here presented applied research and development project is targeted to the development and application of new and improved techniques in plant design, performance analysis and process control. Hereto following the required steps are illustrated and the goals are outlined. The project covers the development of a previously patented anaerobic digestion process, adaption of flow cytometry as an analytical instrument and investigation of innovative ways of disposal of solid fermentation wastes. The preliminary experiences with a newly built research plant employing a novel anaerobic biogas digestion technique are discussed. In this paper the first outcomes concerning the construction and operation are discussed. A novel method of disposal of the fermentation wastes is also discussed and first results are shown

Municipal Solid Waste treatment by integrated solutions: energy and environmental balances

This paper reports a comparison between two scenarios developed in order to manage the municipal solid waste in an area in the North part of Italy. In the proposed scenarios various technological solutions, regarding the selective collection, the energy recovery and the modality of final disposal were taken into account. The comparison was done considering both mass/energy and environmental balance, trying to focus the most suitable solution. The experience can be completed with other scenarios containing different technical solution intermediate between the two considered in this study

Application of strategies for particulate matter reduction in urban areas: an italian case

The paper describes the particulate matter pollution in a Northern Italian city: Varese. The city is distinguished by a particular orographic and meteorological situation, characterized by valleys and heavy rainfalls. Nevertheless the urban area is interested by particulate matter pollution mainly due to heating systems and traffic. Here some corrective strategies in order to reduce PM air pollution have been presented, applied and evaluated by the means of a simplified model which considers emissions and meteorological conditions

Characterization of the PCDD/F in the Province of Trento

Abstract This paper aims to improve the already existing literature data on air concentrations of polychlorinated dibenzo- p -dioxin and dibenzofurans (PCDD/Fs). Four monitoring campaigns were carried out between 2002 and 2010 near Trento, a town in the North of Italy. These campaigns showed relatively low PCDD/F concentrations, in line with the values found in other Italian urban and industrial sites. Typical values for agricultural regions were measured in rural areas, with an increase during winter, possibly due to biomass burning. No critical situations were detected along an important highway, in spite of the non-negligible emission factors for traffic reported in the literature