Selective Collection System Research Articles

Percepção dos Consumidores Sobre Programa de Descarte de Resíduos Recicláveis em Redes Supermercadistas de Porto Alegre

Nowadays, there is a rethinking of the society on how resources are used, which turns to the sustainable development and its relationship concern to the market and business models practiced. In this context there is interest in understanding the role of retail in order to identify the perception of consumers about a program to dispose of recyclable waste disposal, using the infrastructure of the supermarket chains. For this purpose, it was conducted in-depth interviews and a survey. The results of the study indicate that there is demand to sustainable business models. Respondents suggest that the separation of household waste is seen as a social action as well as a way to collaborate with the environment. Furthermore, the results suggest that they did not think it is convenient the proposal of consumers carrying their waste to the supermarkets to dismiss it once there is a selective collection system in Porto Alegre. However, if there is financial gain to consumers, respondents believe that in the short term such initiative can have adherents.

Waste Management in Public Educational Institutions of Bucharest City, Romania

Abstract The educational institutions represent the main components of sustainability promotion in our society. Waste management is one of the challenges that educational institutions have to face in accomplishing sustainability goals. In Bucharest, 457 educational institutions (pre-schools, primary and secondary schools, high schools, special schools) were analyzed using questionnaires. Questionnaires included items related with waste management inside the educational institutions: quantities, collection system characteristics (schedule, selective collection presence, temporary depositing place), responsible for management and influencing factors (total built surface, number of students and educational staff). The results show that most of educational institutions have deficiencies regarding waste management: 47% of the respondents don’t have sufficient information about the generated waste quantities and 49% don’t have waste selective collection systems implemented. Waste quantities generated in educational institutions does not depend on the number of students and the total built surface, but is influenced by the educational institution type. The findings illustrate the difficulty to promote realistic sustainable development actions plans without major changes in public educational institutions from Bucharest.

Modelling municipal waste separation rates using generalized linear models and beta regression

Abstract Most cities are actually very concerned about the economic viability of waste management and also about the impact they may have on the environment. Economical, social and cultural factors in the population will determine the characteristics in waste and the value of the design parameters used in the calculations of a collection system. A clear understanding of these factors is fundamental to plan and to implement efficient and sustainable collecting strategies. Our goal in this work is to model municipal waste separation rates in Spanish cities with over 50,000 inhabitants taking their different socio-economic, demographic and logistic covariates into account. Several statistical regression models to manage continuous proportion data are compared, these being: Generalized linear models (GLM) with Binomial, Poisson and Gamma errors after several transformations of the data and Beta regression on the raw data. The best fits are obtained by using GLM Gamma and beta regression. Significant covariates for the different separation rates are obtained from these models, and the strength of the influence of all these factors on the response variable is calculated. All these results could be taken into account to design and to evaluate selective collection systems, and will allow us to make predictions on cities not included in this study.

Impact of increased collection rates and the use of commingled collection systems on the quality of recovered paper. Part 1: Increased collection rates

The recovery and utilization of recovered paper have increased over past decades all over the world due to economic, environmental, and social issues. However, it is well known that an extended recovered paper collection is detrimental to its quality, either by the exploitation of lower quality sources such as households, or the spreading of commingled systems instead of selective collection systems. The influence of these two factors was assessed by analyzing the quality of different recovered paper grades used as raw material in a mill located in Madrid (Spain) producing newsprint and light weight coated paper from recovered paper. Part 1 of the paper deals with the impact of increased collection rates on the quality of recovered paper and Part 2 with the use of commingled collection systems. Results of Part 1 show that increased collection rates have a large impact on the quality of the recovered paper. The quality, measured as total unusable material and moisture contents, had deteriorated very rapidly in only 4 years (2005–2008) as a consequence of increased collection rates. Collection rates increased in Spain from 58.5% to 68.6% during this period, resulting in more than 50% increase of total unusable material and 25% of moisture content. The downgrading of the quality of recovered paper is one of the major threats for extending the current limits of paper recycling. Therefore, future challenge is to increase its availability but maintaining its quality.

Comparison of different collection systems for sorted household waste in Spain

The purpose of this study was to identify the different selective collection systems implemented in Spanish cities and to analyse the efficiency and extent to which the targets proposed by current law are met in each case. After defining the indicators to be used to quantify the efficiency of a selective collection system, a survey was designed to gather the information needed to calculate them. This survey was sent out to all Spanish cities with a population of over 50,000 inhabitants. Four different selective collection systems were also identified. For each of the four cases the indicators were calculated and analyzed to determine which one was the best system. The best values were obtained from the system with separation in five fractions: paper/cardboard, glass and lightweight packaging at drop-off points, organic waste and mixed waste in kerbside bins. Two regression models (linear and exponential) were developed in systems with enough data to explain and predict the variation in the amounts of materials that were separated correctly into containers, depending on the distance between containers and citizens. Nevertheless, the percentages of separation at source of paper/cardboard and lightweight packaging are still far from reaching the targets set by law.

Resíduos sólidos urbanos – um modelo de gestão em municípios de pequeno e médio porte

Realizar a gestão, gerenciamento e manejo dos resíduos sólidos urbanos é ainda um grande desafio para a maioria dos municípios brasileiros. O administrador público encontra grande dificuldade em organizar a coleta, transporte, tratamento e disposição final destes resíduos, abrangendo todos os aspectos que emvolvem a questão, notadamente os sociais, ambientais, sanitários e legais. Em Lençóis Paulista, cidade com 62.894 habitantes, no Estado de São Paulo, a Prefeitura, apoiada pela Universidade Estadual Paulista (UNESP), Câmpus de Botucatu, concebe um Plano Integrado de Gerenciamento dos Resíduos Sólidos Urbanos(PIGRSU), que identifica a precariedade do sistema de gestão dos resíduos e a omissão da sociedade, em relação a catadores e portadores de necessidades especiais, que sobreviviam da coleta de materiais recicláveis contidos no lixo. O plano reestruturou a Usina de Reciclagem e Compostagem, organizou um sistema de coleta seletiva e remodelou a coleta convencional. Os resultados surgem com a formação de uma cooperativa de catadores, em parceria com a associação de deficientes físicos, gerando inclusão social, aumentando a separação de recicláveis e a vida útil do aterro municipal. Palavras-chave: Reciclagem; Inclusão social; Plano de gerenciamento.

LCA of selective waste collection systems in dense urban areas

This paper presents research concerning the environmental analysis of the selective collection management of municipal solid waste. The main goal of this study is to quantify and to compare, by means of Life Cycle Assessment (LCA), the potential environmental impacts of three selective collection systems modelled on densely populated urban areas. These systems are: the mobile pneumatic, the multi-container and the door-to-door. Impact assessment method based on CML 2 baseline 2000 is applied to the different systems. The study separates and analyzes the collection systems in substages: two urban substages and one inter-city substage. At the urban level, the multi-container system has the least environmental impact of all systems. The mobile pneumatic system has greater environmental impacts in terms of global warming, fresh water aquatic ecotoxicity, terrestrial ecotoxicity, acidification and eutrophication. In this system, the pipes and the pneumatic transport have the greatest impacts. The door-to-door system has a greatest environmental impact in terms of abiotic depletion, ozone layer depletion and human toxicity. An overall evaluation of the three substages, with a sensitivity analysis, indicates that the mobile pneumatic system at an inter-city distance of 20 km shows the greatest environmental impacts and the greatest energy demand. Inter-city transport is key; the results show that from an inter-city distance of 11 km onwards, this becomes the substage which most contributes to global warming impact and energy demand, in all the systems.

Some comparative factors regarding recycling collection systems in regions of the USA and Europe

This paper analyses whether differences in selective waste collection systems used commonly in Europe and America influence people's recycling habits and their opinions about the service they are offered. We study certain characteristics of the collection systems used in two specific areas—the Principality of Asturias (Northern Spain) and El Paso county (USA)—with very different practices. It likewise considers the extent to which such differences influence the recycling habits of the public at large, as well as their perceptions of the waste collection services. In order to carry out the research and to compare the influence of the above-mentioned factors in each case, personal interviews were held in the street in the two areas under study (1066 and 1068 interviews, respectively). Asturians needed less time to dispose of waste and separate items, being one of the reasons why this group has developed the habit of selective separation to a greater degree than El Pasoans.