Analysis of the waste selective collection at drop-off systems: Case study including the income level and the seasonal variation

There are several factors which have an influence in the selective collection of the municipal waste. To define a selective collection system, the waste generation pattern should be firstly determined and these factors should be analyzed in depth. This paper tries to analyze the economic income level and the seasonal variation on the collection and the purity of light-packaging waste to determine actions to improve the waste management plan of a town. In the first stage of the work, waste samples of the light-packaging containers were collected in two zones of the town with different economic characteristics in different seasons during one year. In the second stage, the samples were characterized to analyze the composition and purity of the waste. They were firstly separated into four fractions: metals; plastic; beverage cartons; and misplaced materials. The misplaced fraction was in its turn separated into cardboard, rubber and leather, inert waste, organic matter, paper, hazardous waste, clothes and shoes, glass and others. The plastic fraction was separated into five types of plastics and the metal fraction into three. In the third stage, the data have been analyzed and conclusions have been extracted. The main result is that the quality of the light-packaging fraction collected in these zones during both seasons were similar. This methodology can be extrapolated to towns with similar characteristics. It will be useful when implementing a system to collect the waste selectively and to develop actions to achieve a good participation in the selective collection of the waste

Study of the emissions from pyrolytic and oxidative thermal decomposition of PVC

Polyvinyl chloride (PVC) is one of the plastics most extensively used due to its versatility. The demand of PVC resin in Europe during 2012 reached 5000 ktonnes1. PVC waste management is a big problem because of the high volume generated all over the world and its chlorine content. End-of-life PVC is mainly mixed with municipal solid waste (MSW) and one common disposal option for this is waste-to-energy incineration (WtE). The presence of plastics such as PVC in the fuel mix increases the heating value of the fuel. PVC has two times higher energy content than MSW ‒around 20 MJ/kg vs 10 MJ/kg, respectively. However, the high chlorine content in PVC resin, 57 wt.%, may be a source for the formation of hazardous chlorinated organic pollutants in thermal processes. Chlorine present in the feedstock of WtE plants plays an important role in the formation of (i) chlorine (Cl2) and (ii) hydrochloric gas (HCl), both of them responsible for corrosion, and (iii) chlorinated organic pollutants2. In this work, pyrolytic and oxidative thermal degradation of PVC resin were carried out in a laboratory scale reactor at 500 ºC in order to analyze the influence of the reaction atmosphere on the emissions evolved. Special emphasis was put on the analysis of chlorinated organic pollutants such as polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs) and other related compounds like polychlorobenzenes (PCBzs), polychlorophenols (PCPhs) and polycyclic aromatic hydrocarbons (PAHs). Another objective of this work was to compare the results with those of a previous work3 in which emissions at different temperatures in both pyrolysis and combustion of another PVC resin had been studied; in that case, experiments for PCDD/Fs emissions had been performed only at 850 ºC.Support for this project was provided by the Spanish MEC, research project CTQ2008-05520 and the Valencian Community Government with the research project Prometeo/2009/043/FEDER

Identification and Quantification of Chemical Forms of Cu and Zn in MSWI Ashes Using XANES

Incineration is in many countries a common treatment method for municipal solid waste, and utilization of the ash residues has attracted significant interest. The bottom ash is best suited as a secondary construction material, whereas the fly ash is being investigated as a secondary raw material for recovery of, for example, Zn, Cu, and salts. For both types of application, knowledge about the chemical speciation of Zn and Cu in the ashes is valuable. The present work focuses on identifying and quantifying the chemical species of Zn and Cu in 12 samples of fly ash and bottom ash from three waste-to-energy plants using X-ray absorption near edge structure (XANES). The XANES spectra of the ash samples showed similar distinctive features, and both in the bottom and fly ash samples, the same chemical forms were identified but in various ratios. Cu and Zn occurred in several chemical forms, with typically 5-7 forms present in the same sample. For Cu, the XANES spectra of the fly ash samples were nearly identical, indicating very similar chemical speciation (same chemical forms and similar ratios). Cu was found to exist in various oxide, hydroxide, chloride, silicate, and metallic forms. The most commonly occurring Zn compounds were the aluminate, ferrite, silicate, and oxide along with chloride, basic carbonate (hydrozincite), and occasionally metallic forms, probably alloyed with Cu in brass. Cu occurred in different oxidation states from zero to +II, with a higher prevalence of the lower oxidation states in bottom ash than in fly ash. Zn occurred mainly in oxidation state +II in all ashes analyzed. Finally, we showed that during outdoor storage of bottom ash, levels of Cu and Zn hydroxycarbonates were increased compared to fresh bottom ash. This carbonate formation aims to make Cu and Zn less leachable

The determination of waste generation and composition as an essential tool to improve the waste management plan of a university

When many people work in organized institutions or enterprises, those institutions or enterprises become big meeting places that also have energy, water and resources necessities. One of these necessities is the correct management of the waste that is daily produced by these communities. Universities are a good example of institution where every day a great amount of people go to work or to study. But independently of their task, they use the different services at the University such as cafeterias, canteens, and photocopy and as a result of their activity a cleaning service is also needed. All these activities generate an environmental impact. Nowadays, many Universities have accepted the challenge to minimize this impact applying several measures. One of the impacts to be reduced is the waste generation. The first step to implement measures to implement a waste management plan at a University is to know the composition, the amount and the distribution of the waste generated in its facilities. As the waste composition and generation depend among other things on the climate, these variables should be analysed over one year. This research work estimates the waste generation and composition of a Spanish University, the Universitat Jaume I, during a school year. To achieve this challenge, all the waste streams generated at the University have been identified and quantified emphasizing on those which are not controlled. Furthermore, several statistical analyses have been carried out to know if the season of the year or the day of the week affect waste generation and composition. All this information will allow the University authorities to propose a set of minimization measures to enhance the current management

Viability study of automobile shredder residue as fuel

Car Fluff samples collected from a shredding plant in Italy were classified based on particle size, and three different size fractions were obtained in this way. A comparison between these size fractions and the original light fluff was made from two different points of view: (i) the properties of each size fraction as a fuel were evaluated and (ii) the pollutants evolved when each size fraction was subjected to combustion were studied. The aim was to establish which size fraction would be the most suitable for the purposes of energy recovery. The light fluff analyzed contained up to 50 wt.% fines (particle size < 20 mm). However, its low calorific value and high emissions of polychlorinated dioxins and furans (PCDD/Fs), generated during combustion, make the fines fraction inappropriate for energy recovery, and therefore, landfilling would be the best option. The 50–100 mm fraction exhibited a high calorific value and low PCDD/F emissions were generated when the sample was combusted, making it the most suitable fraction for use as refuse-derived fuel (RDF). Results obtained suggest that removing fines from the original ASR sample would lead to a material product that is more suitable for use as RDF.Support for this work was provided by the Spanish MEC, research project CTQ2008-05520 and by the Valencian Community Government with the research projects Prometeo/2009/043/FEDER

Influence of the Municipal Solid Waste Collection System on the Time Spent at a Collection Point: A Case Study

Waste management plans pay attention to municipal solid waste (MSW) collection systems. It represents a significant portion of waste management as it involves a great economic cost and environmental impact. For these reasons, many researchers have studied the optimization of collection routes, analyzing factors that make them more efficient and sustainable, for example, the overall distance traveled and the time spent on the route. Collection times depend on factors such as the speed of the truck, time at traffic lights or time spent on loading and unloading the waste. The loading and unloading times play an important role in the measurement of the total time of the route. Moreover, there is scarce information in the literature about measuring the real-time spent on the trip. All those times are necessary to optimize the total route time. However, it is difficult to obtain this information directly as it depends on parameters such as the type of truck. The aim of this work is to propose a methodology to define all the times involved in the waste collection process. Once they are well defined, they have to be measured in some cases or calculated in others. This works also presents a case study to validate the proposed methodology with an extensive fieldwork to measure those times that can’t be calculated in the waste collection process. The work presents the results of a study of the time spent at a collection point in six MSW collection systems using different types of collection trucks and bin designs. We have determined how the characteristics of the system affect the time spent at a collection point. Additionally, the times for the six models have been established. Finally, we have determined the influence of the collection model in the duration of the activity. Under certain conditions, times can coincide even though the models are different

Assessment rubric of personal and prosocial competencies and skills

University training for early years and primary school teachers has traditionally focused on highly academic and technical learnings. The extensive experience of our team as teacher trainers has shown us that, in order to complement those learnings, we need to boost our students' personal and prosocial competencies and skills. We consider the acquisition of these competencies and skills to be central to the training to become a teacher, however they are often difficulties to evaluate in a university setting. In order to make these behaviours more visible and to help students, qualified teachers and university tutors to keep them in mind, our research team has created an assessment rubric of personal and prosocial competencies and skills that aim to facilitate awareness and reflection around these specific set of abilities

Efficiency of a pilot scheme for the separate collection of the biowaste from municipal solid waste in Spain

According to EU regulations, member states shall take measures to encourage the recycling of biowaste in a way that fulfils a high level of environmental protection. In Spain, the separate collection of biowaste is only implemented in some regions. For this reason, a pilot scheme based on an information campaign and the location of a specific brown container for biowaste in specific zones of the city was carried out in Castelló de la Plana (Spain) over a period of six months. In this period, the collection and composition of the biowaste was monitored in depth with the goal of determining the evolution of the efficiency of the new collection system over time. In the zones, the quality rate in the biowaste container increased as the pilot study progressed, finally reaching 90%. The rate of biowaste separation also increased in the three zones over time, although in different ways, which means that there is greater collaboration on the part of citizens. On the other hand, an analysis of the rate of net biowaste daily collection from zones 2 and 3 has shown that their value increases as the rate of containerization of biowaste decreases. Therefore, to obtain better results it will be necessary to increase the containerization of biowaste, that is, to reduce the distance from the citizen to the container. It can thus be said that there is a positive evolution of the experience, which boosts confidence when it comes to implementing the system throughout the city

Estudio del yeísmo en el español de Barcelona a partir de materiales de PRESEEA

En enero de 2006, el equipo de investigación sociolingüística de la Universidad de Barcelona, integrado por profesores y doctorandos del Departamento de Filología Hispánica, se incorporó al Proyecto para el Estudio Sociolingüístico del Español de España y de América (PRESEEA), vinculado a la Asociación de Lingüística y Filología de América Latina (ALFAL), y que tiene como coordinador general a Francisco Moreno Fernández, Catedrático de Lengua Española de la Universidad de Alcalá. Dicho proyecto se organiza en una red internacional de equipos de investigación cuyo objetivo central es el de reunir un ingente corpus oral, sociolingüísticamente representativo, de un gran número de ciudades pertenecientes al mundo hispánico. La primera fase del proyecto, que se presentó en 1996, abarca hasta el año 2010 (Moreno Fernández 2006).1 Para el estudio de Barcelona, en el seno del grupo PRESEEA – BARCELONA – ES diseñamos una plantilla que contempla una representación de 108 informantes (los cuales deben haber nacido en la ciudad, haber llegado a ella antes de cumplir los diez años o llevar viviendo en el lugar más de veinte), distribuidos en tres variables de preestratificación: sexo, edad y nivel de instrucción. A este perfil general añadimos la variable ‘lengua primera’ (catalán / español), vista la repercusión que alcanza la convivencia de las dos lenguas en la ciudad (Torres 2007). En las páginas que siguen, nos proponemos abordar el avance real del yeísmo en la Ciudad Condal a partir de unas muestras seleccionadas de los datos de PRESEEABARCELONA- ES. El trabajo, que básicamente es de carácter fonético y presenta un análisis acústico centrado en aspectos frecuenciales, de duración y de intensidad de las muestras mencionadas, pretende ser un primer acercamiento al estadio en el que se encuentra el fenómeno en esta área específica

Archaeopetrological approximation to the lithic procurement of the neolithic axes and adzes from Can Sadurní’s cave (Begues, NE Iberian Peninsula)

Can Sadurní’s cave, located in Begues (NE Iberian Peninsula), in the Baix Llobregat region, is an archaeological site with a wide stratigraphic sequence covering from the Epipaleolithic hunter-gatherers societies at the beginning of the Holocene to Roman times. During the excavations of the last years a large number of different raw materials used for the manufacture of axes have been recovered.The present study is focused on the Neolithic sequence. 31 axes and adzes have been characterised petrographically with the aid of a binocular microscope and transmission microscope. A great variety of rocks constitute the raw materials of these stone tools, ranging from contact and regional metamorphic rocks to plutonic and porphyric igneous rocks. The formers are the most abundant (up to 78%) and include hornfels, spotted phyllites, marbles, quartzites, slates and phyllites. The igneous rocks consist of granodiorite, porphyry and aplites. Such a great assemblage of rocks matches in a geological context representative of a plutonic intrusion and its metamorphic contact aureole. Following that scenario we suggest that the most likely source area for all these materials occur at the Collserola hills, at 27 km far to the east from the cave, at the other side of the Llobregat River, where an Hercynian granodiorite and related igneous rocks intruding Ordovician metasedimentary materials are presented.