RESUMO

The COVID-19 pandemic has greatly impacted the Americas, the continent with the highest number of COVID-related deaths according to WHO statistics. In Latin America, strict confinement conditions at the beginning of the pandemic put recycling activity to a halt and augmented the consumption of plastic as a barrier to stop the spread of the virus. The lack of data to understand waste management dynamics complicates waste management strategy adjustments aimed at coping with COVID-19. As a novel contribution to the waste management data gap for Latin America, this study uses a virtual and participatory methodology that collects and generates information on household solid waste generation and composition. Data was collected between June and November 2021 in six countries in Latin America, with a total of 503 participants. Participants indicated that the pandemic motivated them to initiate or increase waste reduction (41%), waste separation (40%), and waste recovery (33%) activities. Forty-three percent of participants perceived an increase in total volume of their waste; however, the quantitative data showed a decrease in household waste generation in Peru (-31%), Honduras (-25%), and Venezuela (-82%). No changes in waste composition were observed. Despite the limited sample size, this data provides a much-needed approximation of household waste generation and composition in the pandemic situation during 2021.

Assuntos

RESUMO

The Covid-19 pandemic has caused the alteration of many aspects of the solid waste management chain, such as variations in the waste composition, generation and disposal. Various studies have examined these changes with analysis of integrated waste management strategies; qualitative studies on perceived variations and statistical evaluations based on waste collected or disposed in landfills. Despite this information there is a need for updated data on waste generation and composition, especially in developing countries. The objective of this article is to develop a data sampling and analytical approach for the collection of data on household waste generation and composition during the pandemic; and, in addition, estimate the daily generation of masks in the study area. The proposed methodology is based on the principles of citizen science and utilizes virtual tools to contact participants, and for the training and collection of information. The study participants collected the information, installed segregation bins in their homes and trained their relatives in waste segregation. The article presents the results of the application of the methodology in an urban district of Lima (Peru) in August 2020. The results suggest an apparent decrease in household waste per capita and a slight increase in plastics composition in the study area. It is estimated that each participant generates 0.124 masks per day and 0.085 pairs of gloves per day. The method developed and results presented can be used as a tool for public awareness and training on household waste characterization and segregation. Furthermore it can provide the necessary evidence to inform policy directives in response household waste issues and Covid-19 restrictions.

Assuntos

RESUMO

The COVID-19 pandemic has disrupted humans' activities across the globe. Measures related to social/physical distancing and lockdown have led to a shift and increase in waste generated at households' level. This study examined waste generation, composition and the implications for exposure during COVID-19 pandemic lockdown in Guyana and Nigeria. The study adopted a mixed-method design to collect qualitative and quantitative data. Owing to adherence to social/physical distancing, an online Google Form survey was administered and phone interviews were conducted with waste managers in Nigeria and Guyana. Findings showed that the volumes of waste had increased and there was a mixture of Personal Protective Equipment (PPE) with the municipal waste. Also, the majority of the respondents in both countries were concerned that solid waste has the potential to contribute to contamination and spreading of the pandemic. A paired sample T-test analysis indicated an increase in the use of PPE. The values of t = 19.46 and t = 23.73 at p ≥ 0.05 in Nigeria and Guyana, respectively were significant. Waste mostly contaminated, as submitted by the respondents, were cans, bottles, plastics and all biodegradable wastes while the most probable point of contamination as noted by the waste managers occurred at the point of waste collection. Therefore, sorting of waste at household levels and training of personnel involved in waste management should be done with an emphasis on adherence to COVID-19 protocol and enforcement of same to prevent the spread of the virus.

RESUMO

The properties of municipal solid waste (MSW) in landfills vary considerably, depending on the waste's composition, time, and density. This variability in MSW properties leads to many uncertainties in the analysis of landfill performance. Therefore, this study aimed to evaluate landfilled waste's physical, chemical, and mechanical properties for 8 days. Throughout this study, it was possible to investigate the gravimetric composition, density of solid particles, moisture content, volatile solids, pH, total alkalinity, chemical oxygen demand (COD), ammoniacal nitrogen (N-NH3), grain size distribution, compaction properties, and shear strength of the landfilled waste. It was found that 71% of the waste corresponds to the denominated "others" category, the content of fine materials is 65%, the optimum water content is 34%, the moisture content is 41%, and the volatile solids is 67%. The chemical parameters indicated that the MSW was in the initial phase of biodegradation (acidogenesis), as the pH, total alkalinity, COD, and N-NH3 showed to be 5, 1575 mgCaCO3.L-1, 13698.6 mgO2.L-1, and 56 mgN-NH3.L-1, respectively. On the mechanical aspect, the waste presented a cohesion of 17 kPa and an internal friction angle of 16°. In general, the results showed that the waste's physical, chemical, and mechanical properties altered during the landfilling process.

Assuntos

RESUMO

Rejects from selective collection are municipal solid waste (MSW) not used for recycling and are, therefore, destined for the landfill in Brazil. Knowledge of the composition and generation of this waste is important for strategically planning public policies that minimize its generation and its negative environmental impacts. However, this portion of MSW is not very well known. Therefore, the aim of this study was to analyze the rejects from the sorting process of the selective waste collection in the municipality of Blumenau, in the State of Santa Catarina, southern Brazil. The studied rejects came from the largest cooperative in the city, and its composition was sorted into 17 categories of 101 samples over the course of one year, with a total of 3893 kg of analyzed rejects. The waste collected by the selective collection of the municipality was evaluated monthly to determine which part of this quantity became rejects and to determine the composition and seasonality of these rejects. The study found that 30.5% of the waste sorted by the cooperative was rejected. Among these rejects, the presence of materials that could be marketed by the cooperative was verified. Hazardous and/or legally prohibited waste were also identified, as were organics, construction and demolition waste, health care waste, electronics, textiles, footwear, batteries, and bulbs. Seasonal analysis indicated a concerning constant generation of health care waste. Aside from that, there was an increase in the generation of waste from electrical and electronic equipment (EEE) during the Christmas period, when a large part of the population discards their EEE. This information is important for the enforcement of the MSW management structure as well as for educational campaigns aimed at the correct separation of waste that should be sent for selective collection.

Assuntos

RESUMO

Wastes of electrical and electronic equipment (WEEE) represent an important environmental problem, since its composition includes heavy metals and organic compounds used as flame-retardants. Thermal treatments have been considered efficient processes on removal of these compounds, producing carbonaceous structures, which, together with the ceramic components of the WEEE (i.e. silica and alumina), works as support material for the metals. This mixture, associated with the metals present in WEEE, represents promising systems with potential for catalytic application. In this work, WEEE was thermally modified to generate materials that were extensively characterized. Raman spectrum for WEEE after thermal treatment showed two carbon associated bands. SEM images showed a metal nanoparticles distribution over a polymeric and ceramic support. After characterization, WEEE materials were applied in ethanol steam reforming reaction. The system obtained at higher temperature (800°C) exhibited the best activity, since it leads to high conversions (85%), hydrogen yield (30%) and H2/CO ratio (3,6) at 750°C.

Assuntos

RESUMO

State-of-the-art environmental assessment of waste management systems rely on data for the physico-chemical composition of individual material fractions comprising the waste in question. To derive the necessary inventory data for different scopes and systems, literature data from different sources and backgrounds are consulted and combined. This study provides an overview of physico-chemical waste characterisation data for individual waste material fractions available in literature and thereby aims to support the selection of data fitting to a specific scope and the selection of uncertainty ranges related to the data selection from literature. Overall, 97 publications were reviewed with respect to employed characterisation method, regional origin of the waste, number of investigated parameters and material fractions and other qualitative aspects. Descriptive statistical analysis of the reported physico-chemical waste composition data was performed to derive value ranges and data distributions for element concentrations (e.g. Cd content) and physical parameters (e.g. heating value). Based on 11,886 individual data entries, median values and percentiles for 47 parameters in 11 individual waste fractions are presented. Exceptional values and publications are identified and discussed. Detailed datasets are attached to this study, allowing further analysis and new applications of the data.

Assuntos

RESUMO

Business opportunities in the household waste sector in emerging economies still evolve around the activities of bulk collection and tipping with an open material balance. This research, conducted in Brazil, pursued the objective of shifting opportunities from tipping to reverse logistics in order to close the balance. To do this, it illustrated how specific knowledge of sorted waste composition and reverse logistics operations can be used to determine realistic temporal and quantitative landfill diversion targets in an emerging economy context. Experimentation constructed and confirmed the recycling trilogy that consists of source separation, collection infrastructure and reverse logistics. The study on source separation demonstrated the vital difference between raw and sorted waste compositions. Raw waste contained 70% biodegradable and 30% inert matter. Source separation produced 47% biodegradable, 20% inert and 33% mixed material. The study on collection infrastructure developed the necessary receiving facilities. The study on reverse logistics identified private operators capable of collecting and processing all separated inert items. Recycling activities for biodegradable material were scarce and erratic. Only farmers would take the material as animal feed. No composting initiatives existed. The management challenge was identified as stimulating these activities in order to complete the trilogy and divert the 47% source-separated biodegradable discards from the landfills.

Assuntos