Web-GIS oriented systems viability for municipal solid waste selective collection optimization in developed and transient economies

Improving urban waste management: A comprehensive study on household waste generation and spatial patterns in the Grand Guayaquil Metropolitan Area

This study tackles the growing global concern about municipal waste management, particularly in cities like the Grand Guayaquil Metropolitan Area (GGA). Through realistic field studies on in situ household waste generation and geographic information system (GIS) tools, this work offers a framework to predict the quantities and types of recyclable household waste for any metropolitan area in Latin America. Over 4 weeks, students collected, sorted and weighed recyclable waste types, including plastic, paper, metal, glass and fabric, from 776 sampled household of the GGA. ArcGIS survey tool identified household locations and allowed to survey different socio-demographic features. With the help of ArcGIS interpolation method, the total household waste generation for GGA was predicted, and the classification of the different types of recyclable waste was also spatially distributed for the study area. The report identified notable trends in plastic waste, specifically polyethylene terephthalate waste's steady prevalence and 42% growth rate, emphasizing the importance of enhanced recycling techniques. Spatial density maps showed a heterogeneous waste distribution across the GGA, emphasizing locations with higher waste output. This study demonstrates that improving recyclable waste collection can be accomplished with a moderately cheap expenditure by collaborating with academia to overcome knowledge gaps. This strategy provides opportunities to mitigate the environmental impacts of poor waste management.

Smart technological options in collection and transportation of municipal solid waste in urban areas: A mini review

The rapid increase in quantities and the mismanagement of municipal solid waste (MSW) in developing countries are increasing the environmental impacts such as air, water and soil contamination. The present scenario of MSW management deals with numerous issues such as lack of technological resources, strategical management, social awareness, public participation, etc. Globally, numerous efforts in the form of new policies, schemes and regulatory acts have been made to develop a systematic collection and transportation (C&T) method using advanced, integrated technologies. However, very few studies have addressed this issue for low- and middle-income countries due to the lack of availability of reliable resources and data sets. This paper addresses the present challenges in C&T methods and highlights the application of information communication technology in monitoring, capturing, data management, planning, live tracking and communication. This systematic mini-review is based on the availability of technical resources, consumer acceptance and cost-effectiveness of different technologies in managing the processes. The study revealed that the C&T methods in most developed countries are designed based on their geographical stretch, climatic factors, waste characteristics and compatible technology, resulting in sustainable MSW management. However, developing countries have followed the same monotonous approach in managing their MSW, which fails in C&T process. The case study provides a valuable resource for researchers and policymakers to frame a better C&T process based on the recent technological interventions, infrastructure development, and social and economic status.

Environmental and economic assessment of waste collection and transportation using LCA: A case study

The present study is aimed to evaluate the environmental and economic burden associated with current waste collection practices in Dhanbad city, Jharkhand, India. In this study various alternatives were suggested to mitigate these impacts by optimizing resource utilization and maximizing material recovery using life cycle approach. The functional unit adapted is the daily collection service provided for 180 tonnes of municipal solid waste generated in the study area. GaBi 10.6.1 software was used for impact assessment and impacts were assessed for five scenarios in terms of five different impact categories. This study assessed the collection services and treatment options jointly. Baseline scenario (S1) representing the current collection system had the highest impacts on all the impact categories and landfilling contributed the highest (67%) to the overall impacts on the environment. Scenario S2 involved the provision of material recovery facility and considered recycling of plastic wastes having sorting efficiency of 75% which reduced the overall impacts significantly (∼971%) compared to the baseline scenario. Scenario S3 considered composting of food waste (80% food waste sent for composting) and offered further overall impacts reduction (∼1052%) compared to the baseline scenario. In scenario S4, use of electric tippers was accounted which did not offer any significant impacts reductions. Scenario S5 considered the future electricity mix at grid (2030) in India which increased the benefits of using electric tippers. S5 had the least environmental impacts providing overall reductions of ∼1063% compared to baseline scenario and provided maximum economic benefits. Sensitivity analysis results found that variation in recycling had significant change in the environmental impacts. Considering the decrease in recycling rate from 100% to 50%, the impacts on abiotic depletion fossil increased by 136%, acidification by 176%, global warming by 11%, human toxicity by 172% and terrestrial ecotoxicity by 56%.

Evaluation of a data-driven intelligent waste classification system for scientific management of garbage recycling in a Chinese community

Waste classification management is effective in addressing the increasing waste output and continuous deterioration of environmental conditions. The waste classification behaviour of resident is an important basis for managers to collect and allocate resources. Traditional analysis methods, such as questionnaire, have limitations considering the complexity of individual behaviour. An intelligent waste classification system (IWCS) was applied and studied in a community for 1 year. Time-based data analysis framework was constructed to describe the residents' waste sorting behaviour and evaluate the IWCS. The results showed that residents preferred to use face recognition than other modes of identification. The ratio of waste delivery frequency was 18.34% in the morning and 81.66% in the evening, respectively. The optimal time windows of disposing wastes were from 6:55 to 9:05 in the morning and from 18:05 to 20:55 in the evening which can avoid crowding. The percentage of accuracy of waste disposal increased gradually in a year. The amount of waste disposal was largest on every Sunday. The average accuracy was more than 94% based on monthly data, but the number of participating residents decreased gradually. Therefore, the study demonstrates that IWCS is a potential platform for increasing the accuracy and efficiency of waste disposal and can promote regulations implementation.

Smart technologies for collection and classification of electronic waste

Purpose

The main aim of this study is to understand the role of smart technologies and show the rankings of various smart technologies in collection and classification of electronic waste (e-waste).

Design/methodology/approach

This study presents a framework integrating the concepts of collection and classification mechanisms and smart technologies. The criteria set includes three main, which are economic, social and environmental criteria, including a total of 15 subcriteria. Smart technologies identified in this study were robotics, multiagent systems, autonomous tools, smart vehicles, data-driven technologies, Internet of things (IOT), cloud computing and big data analytics. The weights of all criteria were found using fuzzy analytic network process (ANP), and the scores of smart technologies which were useful for collection and classification of e-waste were calculated using fuzzy VlseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR).

Findings

The most important criterion was found as collection cost, followed by pollution prevention and control, storage/holding cost and greenhouse gas emissions in collection and classification of e-waste. Autonomous tools were found as the best smart technology for collection and classification of e-waste, followed by robotics and smart vehicles.

Originality/value

The originality of the study is to propose a framework, which integrates the collection and classification of e-waste and smart technologies.

Sector arc routing-based spatial decision support system for waste collection in Brazil

We present a sector arc routing problem-based spatial decision support system technology to develop tactical and operational plans and manage solid waste collection activities including household refuse collection and human and mechanical street sweeping. The proposed technology can also manage solid waste services through optimization (minimizing sector costs, distances and resources). The proposed technology is called optimized planning and integrated logistics management. It can be directly applied to Brazilian municipalities as it contains its major natural features. The system uses advanced technics from sector arc routing and sector scheduling, fleet and staff scheduling and daily plan management using mobile smartphone apps. The technology also allows for waste system inspections that are transparent to all participants in real time. We present the results of cases evaluated in the field for residential refuse collection and human and mechanical street sweeping in two Brazilian cities (Campo Grande and São Paulo). The plan implementations achieved from 12 to 28% actual fixed and variable cost savings for sectors (vehicles and workers) and routes (time and distances) for residential refuse collection and from 7 to 42% savings for human and mechanical street sweeping for the companies.

What Factors Affect Farmers' Levels of Domestic Waste Sorting Behavior? A Case Study from Shaanxi Province, China

Waste sorting is a key element for solving the current predicament of rural waste management. In the pilot areas of China, farmers' domestic waste sorting behavior (DWSB) varies significantly, whereas there are few studies exploring the mechanism of its formation. To fill this research gap, this study constructs a research model of the internal logic of farmers' waste sorting levels (i.e., no sorting; sorting recyclable waste; sorting recyclable and kitchen waste; and sorting recyclable, kitchen, harmful, and other waste) by considering circumstantial constraints (social norms in external factors) and psychological behavioral antecedents (personal norms and group identity in internal factors). Based on pilot survey data from farmers in Shaanxi Province, China, the results of the ordered logit model indicate that social norms and personal norms were the most significant predictors of the level of DWSB, while group identity was found to have no significant influence. Furthermore, the results of the grouping regression analysis showed that personal norms had a positive moderating effect on the relationship between social norms and farmers' DWSB. Therefore, a more positive social atmosphere, better education, and personal environmental moral responsibility for domestic waste sorting should be established to enhance their levels of waste sorting behavior.

A GIS-based multi-criteria decision support model for planning municipal solid waste collection points: A case study of Çağdaş Neighbourhood, Çiğli District, Izmir, Turkey

This study aims to develop a geographic information system (GIS)-based multi-criteria decision support model to create optimal plans for locating municipal solid waste (MSW) collection points. The model performs a series of consecutive GIS-based spatial analyses to determine alternative plans. Then, it weighs the alternatives considering the social, economic and environmental criteria to determine the optimum solution through analytical hierarchy process. The model was implemented as a case study in Çağdaş neighbourhood of Izmir, Turkey. A total of 42 locations were determined as the optimum collection points out of 245 possible collection points, which yields 39% reduction in collection points compared to the existing system. Total number of waste bins and average walking distance to waste collection points were calculated as 129 and 33 m, respectively. The municipal authority would spend 48.79 $ day^-1 on fuel for waste collection and transport. In addition, daily air pollutant emissions generated during the operations were estimated as 2.052 g CO, 0.231 g NMVOC, 8.409 g NO_x, 0.954 g N₂O, 0.260 g NH₃, 0.000227 g Pb and 0.0231 g PM 2.5. The results indicated that 14 out of 69 collection points in the existing collection system were not allocated to any waste source geographically. This study presents a unique method for planning MSW collection points on two key aspects: (1) development of a novel method to determine all possible collection point locations using Thiessen polygons and (2) presenting a holistic planning method considering the impacts of the collection system on the waste generators and waste collectors.

Gender attitude towards environmental protection: a comparative survey during COVID-19 lockdown situation

Attitude towards environmental protection is a crucial component in environmental safeguard psychology. It is a psychological tendency expressed by evaluating the environmental gender attitude with favour or disfavour. This study aimed to compare the attitude level of male and female trainees towards environmental protection based on personal, psychological and sociocultural variables by using an ex post facto research design. The research population was composed of the trainees (N=177) who participated in the online training programmes organized from April 07 to May 31, 2020, by the Centre for Advanced Agricultural Science and Technology (CAAST) for Climate Smart Agriculture and Water Management (CSAWM), MPKV, Rahuri, Maharashtra, during COVID-19 lockdown period. In this study, an online survey method was used. The research instrument was a well-designed and structured online questionnaire using a Google Form consisting of two sections. The first section consisted of 11 independent variables of personal, psychological and sociocultural characteristics. The second section consisted of 17 environmental attitude questions focusing on closed structure questions with a five-point Likert scale, i.e. Strongly Agree to Strongly Disagree. The results revealed that age, training received, membership of environmental societies or organizations, courses taught, waste management and social media use significantly affect the trainees' attitudes to environment protection. The female respondents had a favourable environmental attitude when compared with the male respondents. Therefore, the study concluded that a set of factors influences the gender attitude of the online trainees. These factors alone cannot change trainees' attitudes towards environmental protection. Accordingly, necessary and appropriate conditions should be provided to change the attitude of male trainees for environmental protection. Sustained support is necessary to efficiently understand the role of gender in environment protection through government policies, social media, policymakers, scientists, extension workers, research organizations, various training programmes, participation of students and faculty in the environmental cleanliness drive and awareness programs, etc.

A review on modern and smart technologies for efficient waste disposal and management

In the current scenario, the word waste management holds much importance in every individual's life. Pollution and the generation of vast waste quantities with no proper waste management process have become one of humanity's biggest threats. This review article provides a complete review of the innovative technologies currently employed to handle and dispose of the waste successfully. This work aims to include the different solid, liquid, gaseous, and radioactive waste management processes. The novel and improved plasma gasification concepts, transmutation, incineration, bio-refineries, microbial fuel cells (MFC) have been thoroughly explained. In addition, some new techniques like Mr. Trash Wheel and the Smart bin approach provide much hope of adequately managing waste. The work's novelty lies in adopting several successful methods of various countries for waste disposal and management. To incorporate or improve India'sIndia's same techniques and processes, we have to tackle the ever-increasing waste disposal problems and find economic and eco-friendly ways of waste management.

Municipal Solid Waste Management Policies, Practices, and Challenges in Ethiopia: A Systematic Review

Municipal Solid Waste Management (MSWM) affects several spheres, including environmental, social, and economic activities. In Ethiopia, massive waste generation and unbalanced management have worsened the issue. Hence, this systematic review investigates the Ethiopian MSWM policy and legal frameworks, practices, and challenges. The Scopus and Web of Science databases and Google Scholar were used to search published and unpublished studies from 2005 to 2021, and a website search was used to find studies from 1995 to 2021. The search was restricted to the English language, and the last search was conducted on 25 June 2021. The study was extracted from the characteristics of the developed study. A risk of bias assessment was conducted for the included studies using the AMSTAR 2. Among the 1135 identified records, 72 studies were found to be eligible. This systematic review identified numerous legal frameworks that enhance the implementation of MSWM in Ethiopia, which is mainly focused on waste collection, transportation, and disposal. Lack of policy enforcement, weak capacity, public awareness, and minimal cooperation among stakeholders were the main challenges. MSWM problems in Ethiopia have seen an increase in recent decades and are affecting daily life. Therefore, these findings may help to improve MSWM in Ethiopia.

Mixed-method approach incorporating Geographic information system (GIS) tools for optimizing collection costs and convenience of the biowaste separate collection

Nowadays, dealing with organic waste (or biowaste) remains a global phenomenon. Especially developing countries worldwide generate more than 50 percent organicwaste. In the European Union (EU) with a share of 34%, biowaste is a dominantfraction of the municipal waste (EEA, 2020). Therefore, separate collection at source and environmentally sound treatment of biowaste are of key importance. An intensive optimisation of biowaste separate collection is needed to balance demands of municipal representatives and households' needs. Based on the mixed-method approach we developed a MCDA model complemented by expert-based weighting assessment and combined with the GIS localisation tools aimed at the optimisation of biowaste container locations that reflects various spatial conditions, preconditions for the localisation of containers and its cost intensity. We concluded that changing the density of containers, distance between the address point and container, and selecting container locations that respect the habits of households and demands of the collection technology significantly affect the total and collection costs. We confirmed that the decreases in the total costs were not significant for maximum walking distances of over 95 m, and would approach zero for distances of over 230 m. When the maximum walking distance exceeds 268 m, 40% of all inhabitants would not participate in the system as it would be inconvenient for them. A recycling campaign is needed to increase their willingness to participate in the system. We provided arguments for decision-makers how to balance convenience of the biowaste separation system and collection costs by proper localisation of biowaste containers.

Formal or informal recycling sectors? Household solid waste recycling behavior based on multi-agent simulation

Urban household solid waste recycling and management are complex adaptive systems with multiple agents, stages, and elements. Previous studies neglected the impact of municipal residents' behavioral decisions on recycling sectors. In this study, the degree of regret-joy and personality characteristics were introduced into a multi-agent-based model to simulate the action decision-making of agents under different strategies. The results demonstrate that, without the government's role, nearly 60% of municipal residents preferred the informal recycling sector (IFRS). Meanwhile, the formal recycling sectors (FRS) find it difficult to attract urban residents because of their low income levels. Regarding a single policy, the subsidy policy is more beneficial than the regulation policy for increasing the income of the FRS from 20 to 250 Yuan. However, neither of the two single policies can weaken the market competitiveness of the IFRS. Moreover, a comprehensive policy combining both subsidies and regulations has enabled more than 60% of urban residents to choose the FRS, thereby increasing its profit and market share to 270 yuan and 500 kg, respectively. These results provide policy suggestions for optimizing the waste recycling management systems.

Cost analysis and optimization of Blockchain-based solid waste management traceability system

As global concerns over End-of-Life (EoL) wastes released to the environment is rising, the need for enhancing the transparency of recycling systems is growing. To address the waste traceability issue, technologies such as Blockchain can be instrumental in the proper disposal and handling of wastes. In this paper, we propose a Blockchain-based Solid Waste Management (SWM) model that can help municipalities enhance the efficiency of their waste management efforts. A Blockchain framework owned and controlled by a municipality is proposed in which customer companies pay to join the platform to avail services from the suppliers managed by the municipality. The cost burdens to both supplier and consumer companies have been discussed. In addition, an optimization model is developed to determine the optimal quantity of waste that can be traded between supplier and consumer companies in order to maximize their profit based on parameters such as the number of suppliers, consumer companies, and the processing capacity of customer companies and several constraints including maximum storing capacity, storage, and transportation constraints. Further, the cost aspects associated with Blockchain implementation are estimated from several use cases obtained from companies providing Blockchain solutions.

A Distributed Architecture for Smart Recycling Using Machine Learning

Recycling is vital for a sustainable and clean environment. Developed and developing countries are both facing the problem of solid management waste and recycling issues. Waste classification is a good solution to separate the waste from the recycle materials. In this work, we propose a cloud based classification algorithm for automated machines in recycling factories using machine learning. We trained an efficient MobileNet model, able to classify five different types of waste. The inference can be performed in real-time on a cloud server. Various techniques are described and used in order to improve the classification accuracy, such as data augmentation and hyper-parameter tuning. Multiple industrial stations are supported and interconnected via custom data transmission protocols, along with security features. Experimental results indicated that our solution can achieve excellent performance with 96.57% accuracy utilizing a cloud server.

From intention to behavior: Comprehending residents' waste sorting intention and behavior formation process

Waste sorting is essential to address the current predicament of waste management. Though it is important, insufficient attention has been paid to explore residents' waste sorting intention and behavior and understand its formation process. To narrow the research gap, this research built a theoretical research model by adding personal moral norms and waste sorting knowledge into the theory of planned behavior to explicate residents' waste sorting intention and behavior formation process. Meanwhile, given the discrepancy between waste sorting intention and actual behavior, this research also explored the effect of external conditions, such as incentive measures, on this discrepancy. Based on survey data from 397 Chinese residents, this research found that attitudes, subjective norms, perceived behavioral control, personal moral norms and waste sorting knowledge were directly and significantly related to residents' waste sorting intention. Waste sorting knowledge also had an indirect influence on residents' waste sorting intention through attitudes and perceived behavioral control. Additionally, this research corroborated the discrepancy between waste sorting intention and behavior, and suggested that the link between intention and behavior was contingent on incentive measures. Incentive measures strengthened the effect of intention on behavior. This research is useful for understanding residents' waste sorting intention and behavior and valuable for encouraging residents to sort waste in their daily lives.

A Door-to-Door Waste Collection System Case Study: A Survey on its Sustainability and Effectiveness

Municipal waste management is a relevant topic these days, in its relation to sustainable and environmental concerns. Sorting waste fractions at home for a door-to-door collection system proves to positively affect the environmental impacts of waste management strategies both by reducing the amounts of the waste landfilled and by originating new circular economies. However, the environmental impact caused by both waste collection and transport, together with waste quality, should be carefully evaluated to assess the sustainability of such a collection system. In order to evaluate the logistic and environmental effectiveness of a newly implemented door-to-door collection system in Altamura, a mid-sized town in Southern Italy, a survey was designed and submitted to a sample of citizens. The results obtained from the 385 completed surveys show that the door-to-door collection of glass waste is inefficient since most of the designated bins remain partially filled and less frequently delivered; citizens are more motivated to adequately collect sorted waste fractions upon receiving information about the subsequent environmental benefits and outcomes of the fractions collected; a high percentage of people still use disposable items in their daily life. Possible changes to the weekly bins collection schedule have been proposed in order to have a more proficient and environmentally sustainable waste collection service in the town. The survey is part of a project aiming at developing a smart device to support users in home waste management.

A proposed sustainable and digital collection and classification center model to manage e-waste in emerging economies

Purpose

This study aims to propose an electronic waste collection and classification system to enhance social, environmental and economic sustainability by integrating data-driven technologies in emerging economies.

Design/methodology/approach

GM (1, 1) model under grey prediction is used in this study in order to estimate the trend of the amount of collected electronic waste in emerging economies.

Findings

It is revealed that the amount of collected electronic waste is increasing day by day, and within the framework of sustainability in the process of collecting and classification of electronic waste, digital technologies were found to be lacking. It has been determined that this deficiency, together with the increasing amount of electronic waste, has caused environmental, social and economic damage to emerging economies.

Originality/value

The main originality of this study is integrating electronic waste collection and classification processes with data-driven technologies and sustainability, which is a relatively new subject.

Developing successful environmental decision support systems: Challenges and best practices

Environmental decision support systems (EDSSs), or DSS applied in the environmental field, have been developed for over 40 years now. However, most of these tools fail to find use or fall out of use extremely quickly. In the aim of aiding in the conception and development of practical and successful decision support systems, i.e. systems that can lead to positive outcomes, this review looks over the existing literature, both EDSS-centric and from broader decision-related fields, to highlight some of the most important challenges influencing the success and usability of these systems. In all, 13 major challenges facing EDSS development were identified and over 60 recommendations and best practices were provided to address these challenges. Though this paper is mainly focused on environmental decision support systems, most of the highlighted information and conclusions are applicable to the development of decision support systems in any field.

Recycling sustainability of waste paper industry in Beijing City: An analysis based on value chain and GIS model

China established a self-organized and market-driven recycling system, which was dominated by the informal sectors. In recent years, the amount of domestically-recycled waste paper grew slower than expectation in China, which may be resulted from a decline in economic sustainability of current recycling system. For understanding the waste paper recycling system in most cities in China, the economic mechanism remains unclear and the city-level data is extremely insufficient. In this work, an index of recycling sustainability (IRS, benefit divided by cost) is analyzed with a resolution of 1 km² grid in Beijing City, by adopting value chain and GIS methodology. Five degrees of IRS are defined, from high-degree (IRS > 1.10) to low-degree (IRS < 0.95). Different stakeholders in the informal waste paper recycling system were interviewed to fill the data gap. Results show that: (1) from 2015 to 2018, the informal recycling of waste paper accounted for approximate 80% in Beijing; (2) the number of informal recyclables distribution sites decreased from 27 to 11, and their average distance to the city-center rose from 27.5 km to 40.9 km; (3) in 2015 and 2018, the grids with high-degree IRS accounted for 99.5% and 89.2%, respectively, indicating a sustainable waste paper recycling industry in Beijing; and (4) according to the scenario analysis, if the operating cost rises by 30%, the grids with low-degree IRS accounts for 98.5%, indicating a nontrivial challenges when the recycling cost keeps increasing in the future. Policy recommendations are put forward for a more sustainable paper waste recycling system in China.

Remote sensing and GIS applications for municipal waste management

The production of municipal solid waste has increased noticeably during the recent past due to the mounting global population and fast urbanization. Furthermore, its poor management and inappropriate disposal are a global challenge since these have created environmental problems in urban ecosystems. Waste management problems are significantly stalled because of a lack of quality data. This is particularly the case in developing countries where observation infrastructure is weak. Regional waste management strategies involve distributed data, while typical small-scale studies present just point information and in the lack of vital widespread information, the regional studies can't provide dependable results. With the materialization of new techniques such as remote sensing and GIS, regional waste management studies have become easier during the last few decades. Use of these techniques in solid waste management supports in capturing, handling, and transmitting the required information in a prompt and proper manner. These techniques are also useful in acquiring information directly from the remote site at a fairly low cost. This paper provides an overview of remote sensing and GIS techniques used for managing the environmental problems of waste disposal. An indication of the waste disposal problems and its management alongside the ramifications of the analysis is discussed. The background and rationale of the waste disposal problems are detailed. The applications of remote sensing and GIS in waste management modeling are presented and applications of these techniques in diverse case studies worldwide are described. The study revealed that the efficiency of waste management system can be maximized by the proper use of remote sensing and GIS techniques. The study also revealed that these techniques were most commonly used for siting the landfill and waste bin for waste disposal and evaluation of environmental impact of buried waste.

Multi-stage optimization approach for sustainable municipal solid waste collection systems in urban areas of Asia's newly industrialized countries

A multi-stage optimization approach for sustainable collection system design for urban municipal solid waste is developed for megacities in Asia's newly industrialized countries. The approach combines four methods-analysis of waste and area characteristics, data acquisition and evaluation by GIS, mathematical projection of existing and future collection systems, and identification of most suitable alternatives through comparative multi-criteria decision analysis (MCDA). The approach is applied in Bangalore, India with 1.66 million inhabitants and 46.7-km² area of investigation, and stratified based on population density. Two possible collection mechanisms (door-to-door (D2D) and community bin (CB)) are analyzed with a varied combination of collection coverage and waste segregation level. The study results confirm that both operational and investment expenses of the collection system decrease with an increasing rate of CB collection. Moreover, overall CO₂ emissions of waste collection from the entire area of investigation decrease from 5.2 to 3.1 tons per day if the present 100% D2D collection is replaced with 100% CB collection system. Also, the increase of segregation at source contributes to the reduction of operational expenses and CO₂ emissions; for example, a 20% increase of segregation level for D2D collection system leads to a 6% reduction of CO₂ emissions. Considering all decision parameters through MCDA, a collection system comprising only CB with one separate compartment for wet waste and another combined compartment for dry and mixed waste is determined to be the most favorable approach.

From intention to action: How do personal attitudes, facilities accessibility, and government stimulus matter for household waste sorting?

There is a notable discrepancy between intention on household waste sorting and the actions taken to support this environmental initiative among residents in China. This study aims to explore the influences of personal attitudes, facilities accessibility, and government stimulus on this discrepancy. Built on an integrated framework of Theory of Planned Behaviour (TPB) and Norm Activation Model (NAM), this study examines the relationship between intention and household waste sorting behaviour considering the psychological behavioural antecedents and circumstantial constraints among Chinese residents. Results from a questionnaire survey administered in China confirm the discrepancy, and show that the link between intention and behaviour on waste sorting is weakened after adding the influencing paths from the factors of facilities accessibility and government stimulus to waste sorting behaviour: however, the presence of these two factors directly promote waste sorting behaviour, but do not moderate the intention-behaviour relationship as their interaction items with behavioural intention are not significantly related to waste sorting behaviour. Furthermore, the personal norm is found to be the major factor influencing intentions of Chinese residents towards waste sorting while both subjective norms and perceived behavioural control were unexpectedly found to have no significant influence thereon. These findings are useful for promotion and planning of waste sorting by policy-makers to ease the waste disposal problem.

The future of waste management in smart and sustainable cities: A review and concept paper

The potential of smart cities in remediating environmental problems in general and waste management, in particular, is an important question that needs to be investigated in academic research. Built on an integrative review of the literature, this study offers insights into the potential of smart cities and connected communities in facilitating waste management efforts. Shortcomings of existing waste management practices are highlighted and a conceptual framework for a centralized waste management system is proposed, where three interconnected elements are discussed: (1) an infrastructure for proper collection of product lifecycle data to facilitate full visibility throughout the entire lifespan of a product, (2) a set of new business models relied on product lifecycle data to prevent waste generation, and (3) an intelligent sensor-based infrastructure for proper upstream waste separation and on-time collection. The proposed framework highlights the value of product lifecycle data in reducing waste and enhancing waste recovery and the need for connecting waste management practices to the whole product life-cycle. An example of the use of tracking and data sharing technologies for investigating the waste management issues has been discussed. Finally, the success factors for implementing the proposed framework and some thoughts on future research directions have been discussed.

A stochastic optimization framework for planning of waste collection and value recovery operations in smart and sustainable cities

The concept of City 2.0 or smart city is offering new opportunities for handling waste management practices. The existing studies have started addressing waste management problems in smart cities mainly by focusing on the design of new sensor-based Internet of Things (IoT) technologies, and optimizing the routes for waste collection trucks with the aim of minimizing operational costs, energy consumption and transportation pollution emissions. In this study, the importance of value recovery from trash bins is highlighted. A stochastic optimization model based on chance-constrained programming is developed to optimize the planning of waste collection operations. The objective of the proposed optimization model is to minimize the total transportation cost while maximizing the recovery of value still embedded in waste bins. The value of collected waste is modeled as an uncertain parameter to reflect the uncertain value that can be recovered from each trash bin due to the uncertain condition and quality of waste. The application of the proposed model is shown by using a numerical example. The study opens new venues for incorporating the value recovery aspect into waste collection planning and development of new data acquisition technologies that enable municipalities to monitor the mix of recyclables embedded in individual trash bins.

Technologies and decision support systems to aid solid-waste management: a systematic review

Population growth associated with population migration to urban areas and industrial development have led to a consumption relation that results in environmental, social, and economic problems. With respect to the environment, a critical concern is the lack of control and the inadequate management of the solid waste generated in urban centers. Among the challenges are proper waste-collection management, treatment, and disposal, with an emphasis on sustainable management. This paper presents a systematic review on scientific publications concerning decision support systems applied to Solid Waste Management (SWM) using ICTs and OR in the period of 2010-2013. A statistical analysis of the eighty-seven most relevant publications is presented, encompassing the ICTs and OR methods adopted in SWM, the processes of solid-waste management where they were adopted, and which countries are investigating solutions for the management of solid waste. A detailed discussion on how the ICTs and OR methods have been combined in the solutions was also presented. The analysis and discussion provided aims to help researchers and managers to gather insights on technologies/methods suitable the SWM challenges they have at hand, and on gaps that can be explored regarding technologies/methods that could be useful as well as the processes in SWM that currently do not benefit from using ICTs and OR methods.

Assessment strategies for municipal selective waste collection schemes

An important strategy to promote a strong sustainable growth relies on an efficient municipal waste management, and phasing out waste landfilling through waste prevention and recycling emerges as a major target. For this purpose, effective collection schemes are required, in particular those regarding selective waste collection, pursuing a more efficient and high quality recycling of reusable materials. This paper addresses the assessment and benchmarking of selective collection schemes, relevant to guide future operational improvements. In particular, the assessment is based on the monitoring and statistical analysis of a core-set of performance indicators that highlights collection trends, complemented with a performance index that gathers a weighted linear combination of these indicators. This combined analysis underlines a potential tool to support decision makers involved in the process of selecting the collection scheme with best overall performance. The presented approach was applied to a case study conducted in Oporto Municipality, with data gathered from two distinct selective collection schemes.

A mathematical model for municipal solid waste management - A case study in Hong Kong

With the booming economy and increasing population, the accumulation of waste has become an increasingly arduous issue and has aroused the attention from all sectors of society. Hong Kong which has a relative high daily per capita domestic waste generation rate in Asia has not yet established a comprehensive waste management system. This paper conducts a review of waste management approaches and models. Researchers highlight that mathematical models provide useful information for decision-makers to select appropriate choices and save cost. It is suggested to consider municipal solid waste management in a holistic view and improve the utilization of waste management infrastructures. A mathematical model which adopts integer linear programming and mixed integer programming has been developed for Hong Kong municipal solid waste management. A sensitivity analysis was carried out to simulate different scenarios which provide decision-makers important information for establishing Hong Kong waste management system.

An investigation of the usability of sound recognition for source separation of packaging wastes in reverse vending machines

In this study, we investigate the usability of sound recognition for source separation of packaging wastes in reverse vending machines (RVMs). For this purpose, an experimental setup equipped with a sound recording mechanism was prepared. Packaging waste sounds generated by three physical impacts such as free falling, pneumatic hitting and hydraulic crushing were separately recorded using two different microphones. To classify the waste types and sizes based on sound features of the wastes, a support vector machine (SVM) and a hidden Markov model (HMM) based sound classification systems were developed. In the basic experimental setup in which only free falling impact type was considered, SVM and HMM systems provided 100% classification accuracy for both microphones. In the expanded experimental setup which includes all three impact types, material type classification accuracies were 96.5% for dynamic microphone and 97.7% for condenser microphone. When both the material type and the size of the wastes were classified, the accuracy was 88.6% for the microphones. The modeling studies indicated that hydraulic crushing impact type recordings were very noisy for an effective sound recognition application. In the detailed analysis of the recognition errors, it was observed that most of the errors occurred in the hitting impact type. According to the experimental results, it can be said that the proposed novel approach for the separation of packaging wastes could provide a high classification performance for RVMs.

Content-based image retrieval system for solid waste bin level detection and performance evaluation

This paper presents a CBIR system to investigate the use of image retrieval with an extracted texture from the image of a bin to detect the bin level. Various similarity distances like Euclidean, Bhattacharyya, Chi-squared, Cosine, and EMD are used with the CBIR system for calculating and comparing the distance between a query image and the images in a database to obtain the highest performance. In this study, the performance metrics is based on two quantitative evaluation criteria. The first one is the average retrieval rate based on the precision-recall graph and the second is the use of F1 measure which is the weighted harmonic mean of precision and recall. In case of feature extraction, texture is used as an image feature for bin level detection system. Various experiments are conducted with different features extraction techniques like Gabor wavelet filter, gray level co-occurrence matrix (GLCM), and gray level aura matrix (GLAM) to identify the level of the bin and its surrounding area. Intensive tests are conducted among 250 bin images to assess the accuracy of the proposed feature extraction techniques. The average retrieval rate is used to evaluate the performance of the retrieval system. The result shows that, the EMD distance achieved high accuracy and provides better performance than the other distances.

An algorithm for the optimal collection of wet waste

This work refers to the development of an approach for planning wet waste (food waste and other) collection at a metropolitan scale. Some specific modeling features distinguish this specific waste collection problem from the other ones. For instance, there may be significant differences as regards the values of the parameters (such as weight and volume) characterizing the various collection points. As it happens for classical waste collection planning, even in the case of wet waste, one has to deal with difficult combinatorial problems, where the determination of an optimal solution may require a very large computational effort, in the case of problem instances having a noticeable dimensionality. For this reason, in this work, a heuristic procedure for the optimal planning of wet waste is developed and applied to problem instances drawn from a real case study. The performances that can be obtained by applying such a procedure are evaluated by a comparison with those obtainable via a general-purpose mathematical programming software package, as well as those obtained by applying very simple decision rules commonly used in practice. The considered case study consists in an area corresponding to the historical center of the Municipality of Genoa.

Fast methodology to design the optimal collection point locations and number of waste bins: A case study

This paper concerns the development of a methodology aimed at determining the optimal number of waste bins as well optimizing the location of collection points. The methodology was based on a geographic information system, which handled different sets of information, such as street directions, spatial location of objects and number of inhabitants, location of waste bins, and radius of their coverage. The study was conducted in a district in the central area of the city of Kragujevac. Due to a lack of information about the existing situation, all necessary data was collected by fieldwork and by using GPS equipment. By using the developed methodology, the results indicated a reduction of 24% in the number of collection points and 33.5% in the number of waste bins, without reducing the quality of the provided services. It has led to cost and time savings for waste collection and environmental benefits. All users of the services were covered within a 75-m radius, and the usage of bins is more efficient. According to the reduction in the number of waste bins, a total amount of €26,000 may be achieved. In addition, the time for waste collection was reduced, resulting in a €1700 saving per year in fuel costs, as well as 4.5 tons of emitted CO2 into the atmosphere.

Optimization of municipal solid waste collection and transportation routes

Optimization of municipal solid waste (MSW) collection and transportation through source separation becomes one of the major concerns in the MSW management system design, due to the fact that the existing MSW management systems suffer by the high collection and transportation cost. Generally, in a city different waste sources scatter throughout the city in heterogeneous way that increase waste collection and transportation cost in the waste management system. Therefore, a shortest waste collection and transportation strategy can effectively reduce waste collection and transportation cost. In this paper, we propose an optimal MSW collection and transportation scheme that focus on the problem of minimizing the length of each waste collection and transportation route. We first formulize the MSW collection and transportation problem into a mixed integer program. Moreover, we propose a heuristic solution for the waste collection and transportation problem that can provide an optimal way for waste collection and transportation. Extensive simulations and real testbed results show that the proposed solution can significantly improve the MSW performance. Results show that the proposed scheme is able to reduce more than 30% of the total waste collection path length.

A review on technologies and their usage in solid waste monitoring and management systems: Issues and challenges

In the backdrop of prompt advancement, information and communication technology (ICT) has become an inevitable part to plan and design of modern solid waste management (SWM) systems. This study presents a critical review of the existing ICTs and their usage in SWM systems to unfold the issues and challenges towards using integrated technologies based system. To plan, monitor, collect and manage solid waste, the ICTs are divided into four categories such as spatial technologies, identification technologies, data acquisition technologies and data communication technologies. The ICT based SWM systems classified in this paper are based on the first three technologies while the forth one is employed by almost every systems. This review may guide the reader about the basics of available ICTs and their application in SWM to facilitate the search for planning and design of a sustainable new system.

Use of genetic algorithms to improve the solid waste collection service in an urban area

Increasing generation of Urban Solid Waste (USW) has become a significant issue in developing countries due to unprecedented population growth and high rates of urbanisation. This issue has exceeded current plans and programs of local governments to manage and dispose of USW. In this study, a Genetic Algorithm for Rule-set Production (GARP) integrated into a Geographic Information System (GIS) was used to find areas with socio-economic conditions that are representative of the generation of USW constituents in such areas. Socio-economic data of selected variables categorised by Basic Geostatistical Areas (BGAs) were taken from the 2000 National Population Census (NPC). USW and additional socio-economic data were collected during two survey campaigns in 1998 and 2004. Areas for sampling of USW were stratified into lower, middle and upper economic strata according to income. Data on USW constituents were analysed using descriptive statistics and Multivariate Analysis. ARC View 3.2 was used to convert the USW data and socio-economic variables to spatial data. Desk-top GARP software was run to generate a spatial model to identify areas with similar socio-economic conditions to those sampled. Results showed that socio-economic variables such as monthly income and education are positively correlated with waste constituents generated. The GARP used in this study revealed BGAs with similar socio-economic conditions to those sampled, where a similar composition of waste constituents generated is expected. Our results may be useful to decrease USW management costs by improving the collection services.

Quantitative assessment of distance to collection point and improved sorting information on source separation of household waste

The present study measures the participation of households in a source separation scheme and, in particular, if the household's application of the scheme improved after two interventions: (a) shorter distance to the drop-off point and (b) easy access to correct sorting information. The effect of these interventions was quantified and, as far as possible, isolated from other factors that can influence the recycling behaviour. The study was based on households located in an urban residential area in Sweden, where waste composition studies were performed before and after the interventions by manual sorting (pick analysis). Statistical analyses of the results indicated a significant decrease (28%) of packaging and newsprint in the residual waste after establishing a property close collection system (intervention (a)), as well as significant decrease (70%) of the miss-sorted fraction in bags intended for food waste after new information stickers were introduced (intervention (b)). Providing a property close collection system to collect more waste fractions as well as finding new communication channels for information about sorting can be used as tools to increase the source separation ratio. This contribution also highlights the need to evaluate the effects of different types of information and communication concerning sorting instructions in a property close collection system.

Waste container weighing data processing to create reliable information of household waste generation

Household mixed waste container weighing data was processed by knowledge discovery and data mining techniques to create reliable information of household waste generation. The final data set included 27,865 weight measurements covering the whole year 2013 and it was selected from a database of Helsinki Region Environmental Services Authority, Finland. The data set contains mixed household waste arising in 6m(3) containers and it was processed identifying missing values and inconsistently low and high values as errors. The share of missing values and errors in the data set was 0.6%. This provides evidence that the waste weighing data gives reliable information of mixed waste generation at collection point level. Characteristic of mixed household waste arising at the waste collection point level is a wide variation between pickups. The seasonal variation pattern as a result of collective similarities in behaviour of households was clearly detected by smoothed medians of waste weight time series. The evaluation of the collection time series against the defined distribution range of pickup weights on the waste collection point level shows that 65% of the pickups were from collection points with optimally dimensioned container capacity and the collection points with over- and under-dimensioned container capacities were noted in 9.5% and 3.4% of all pickups, respectively. Occasional extra waste in containers occurred in 21.2% of the pickups indicating the irregular behaviour of individual households. The results of this analysis show that processing waste weighing data using knowledge discovery and data mining techniques provides trustworthy information of household waste generation and its variations.

Methodology to design a municipal solid waste generation and composition map: a case study

The municipal solid waste (MSW) management is an important task that local governments as well as private companies must take into account to protect human health, the environment and to preserve natural resources. To design an adequate MSW management plan the first step consists in defining the waste generation and composition patterns of the town. As these patterns depend on several socio-economic factors it is advisable to organize them previously. Moreover, the waste generation and composition patterns may vary around the town and over the time. Generally, the data are not homogeneous around the city as the number of inhabitants is not constant nor it is the economic activity. Therefore, if all the information is showed in thematic maps, the final waste management decisions can be made more efficiently. The main aim of this paper is to present a structured methodology that allows local authorities or private companies who deal with MSW to design its own MSW management plan depending on the available data. According to these data, this paper proposes two ways of action: a direct way when detailed data are available and an indirect way when there is a lack of data and it is necessary to take into account bibliographic data. In any case, the amount of information needed is considerable. This paper combines the planning methodology with the Geographic Information Systems to present the final results in thematic maps that make easier to interpret them. The proposed methodology is a previous useful tool to organize the MSW collection routes including the selective collection. To verify the methodology it has been successfully applied to a Spanish town.

Analysis of Material and Information Flows and Formulation of an ICT Waste Management Model

The generation and accumulation of waste of electrical and electronic equipment (WEEE) is growing fast, becoming one of the most complex waste streams the modern world faces. The effective and efficient management of this waste stream raises the interest of the global scientific and business community. The purpose of this paper is to analyze the flow in an e-waste management system, present the main processes included and detect the information procedures that affect the operation of the system. For its research, first a detailed literature review is presented and second the critical information flows are analyzed. The findings indicate five critical informational procedures of managerial concern: (a) defining the infrastructure, technological systems, and investments that are needed to optimize an e-waste management network, (b) minimizing the total cost of the e-waste management system, (c) estimating ICT waste quantities as precisely as possible, (d) selecting the appropriate strategy for ICT waste treatment, and (e) redesigning the IT and telecommunication products in order to improve their recycling characteristics. The study concludes with the formulation and presentation of a material and information flow diagram of ICT waste management system.

Methodology to design a municipal solid waste generation and composition map: a case study

The municipal solid waste (MSW) management is an important task that local governments as well as private companies must take into account to protect human health, the environment and to preserve natural resources. To design an adequate MSW management plan the first step consist in defining the waste generation and composition patterns of the town. As these patterns depend on several socio-economic factors it is advisable to organize them previously. Moreover, the waste generation and composition patterns may vary around the town and over the time. Generally, the data are not homogeneous around the city as the number of inhabitants is not constant nor it is the economic activity. Therefore, if all the information is showed in thematic maps, the final waste management decisions can be made more efficiently. The main aim of this paper is to present a structured methodology that allows local authorities or private companies who deal with MSW to design its own MSW management plan depending on the available data. According to these data, this paper proposes two ways of action: a direct way when detailed data are available and an indirect way when there is a lack of data and it is necessary to take into account bibliographic data. In any case, the amount of information needed is considerable. This paper combines the planning methodology with the Geographic Information Systems to present the final results in thematic maps that make easier to interpret them. The proposed methodology is a previous useful tool to organize the MSW collection routes including the selective collection. To verify the methodology it has been successfully applied to a Spanish town.

Critical analysis of the integration of residual municipal solid waste incineration and selective collection in two Italian tourist areas

Municipal solid waste management is not only a contemporary problem, but also an issue at world level. In detail, the tourist areas are more difficult to be managed. The dynamics of municipal solid waste production in tourist areas is affected by the addition of a significant amount of population equivalent during a few months. Consequences are seen in terms of the amount of municipal solid waste to be managed, but also on the quality of selective collection. In this article two case studies are analyzed in order to point out some strategies useful for a correct management of this problem, also taking into account the interactions with the sector of waste-to-energy. The case studies concern a tourist area in the north of Italy and another area in the south. Peak production is clearly visible during the year. Selective collection variations demonstrate that the tourists' behavior is not adequate to get the same results as with the resident population.

Sewage sludge drying by energy recovery from OFMSW composting: preliminary feasibility evaluation

In this paper an original energy recovery method from composting is analyzed. The integrated system exploits the heat available from the aerobic biochemical process in order to support the drying of sewage sludge, using a specific solar greenhouse. The aim is to tackle the problem of organic waste treatment, with specific regard to food waste. This is done by optimizing the energy consumption of the aerobic process of composting, using the heat produced to solve a second important waste management problem such as the sewage waste treatment. Energy and mass balances are presented in a preliminary feasibility study. Referring to a composting plant with a capacity of 15,000 t/y of food waste, the estimation of the power from recovered heat for the entire plant resulted about 42 kW. The results demonstrated that the energy recoverable can cover part of the heat necessary for the treatment of sludge generated by the population served by the composting plant (in terms of food waste and green waste collection). The addition of a renewable source such as solar energy could cover the residual energy demand. The approach is presented in detail in order for it to be replicated in other case studies or at full scale applications.