Proceedings of the World Conference on Waste Management
Proceedings of the World Conference on Waste Management is an open - access double blind peer-reviewed conference proceeding which publishes original scientific research papers, reviews and case studies within the scope of Waste Management and Environmental Studies. Learn more about WCWM Conference
This work is licensed under a Creative Commons Attribution 4.0 International License.
IMPLEMENTING A SUSTAINABLE WASTE REDUCTION STRATEGY: A CASE STUDY AT GENERAL MOTORS
In congruence with General Motors launching a Zero Waste circular economy program, it has committed to diverting more than 90% of operational waste from landfills and thermal processing facilities by 2025. To achieve this goal for GM North America, a methodical waste reduction program was developed through the amalgamation of two interrelated strategies, the Strategic Planning Process and the Operational Strategy Process. This dual approach benefits from a companywide integrated focus on the organization’s strategic goals, yet remains efficient and engaging on a facility level, allowing for operational flexibility of design. To implement this novel methodology, GM established the team-of-teams approach to program management, creating roles in both the Sustainability team and Strategic Programs & Partnerships (SP2) team. The Sustainability team took ownership of the Strategic Planning Process, designing the Zero Waste tracking methodology and establishing annual waste diversion targets for the corporation. The SP2 team led the Operational Strategy Process, owning the specific Zero Waste Budget, and creating waste-centric innovation workshops, such as the Zero Waste Treasure Hunt program and Zero Waste Mini-Missions, which focused on quality improvement techniques, such as PDCA (Plan-Do-Check-Act) and DMAIC (Define-Measure-Analyze-Improve-Control). Projects that are ideated through the program are then submitted through the Zero Waste Projects Module, where they are reviewed based on various funding guidelines and prioritization benchmarks, ensuring funds are awarded to high impact ventures. This methodology has proven successful in surpassing 2021 diversion targets, with a real world 2021 diversion rate of 86.4%, and setting the groundwork to further expand support to meet the company’s Zero Waste diversion glidepath through 2025.
Copyright (c) 2022 Proceedings of the World Conference on Waste Management http://creativecommons.org/licenses/by/4.0
CLASSIFYING AND MANAGING OF ASBESTOS CONTAINING WASTE: ITALIAN EXPERIENCE
Until the 1990s Italy was the first world producer of asbestos, although in 1992 it became one of the first countries to ban this substance internationally, introducing law 257/1992, which prohibits the extraction and production of asbestos and asbestos containing products. The aim of this job is to describe some international experiences in the field of asbestos containing waste (ACW) management, focusing on the acceptance of waste in landfills and deposits and/or pre-treatment centers. In particular, the methodology envisages the analysis of the European and Italian legislation, study of waste classification and management in the main European countries, data analysis of mapping of Italian landfills and quantification of ACW disposed there. The results show criticalities on the classification and management of ACW or non-compliance on a local scale with European and National regulations. Such inconsistencies are the result of an inadequate interpretation of the sector legislation, which is complex and articulated, while, in other cases, of intentional illegal activities. In this paper the main problems of the sector are will be highlighted, and it could be a useful tool for a better classification and management of the ACW. These indications could also be adopted as a reference by various public authorities and trade associations involved in the management of this type of waste. Finally, this study will report the specific tables with indications on the main ACW, on the relevant European waste classification codes to be applied and on the correct final destination in landfills where they should be disposed of; it is a useful manual for classifying worldwide ACPs (asbestos containing products) based on their physical state.
MAKING A DECISION USING ANALYTICAL HIERARCHY PROCESS (AHP) IN SELECTING SUITABLE FOOD WASTE MANAGEMENT METHOD: A CONCEPTUAL FRAMEWORK
Food waste in Malaysia has the highest composition in municipal solid waste (MSW) stream which, occupied around 44.5% of the total waste in mass. As food wastes are commonly disposed to landfill, during the process of degradation, it produces harmful pollutants such as leachate which cause contamination to the water sources while landfill gases lead to global warming and climate change. However, land scarcity is an issue in Malaysia where it is soon coming into a limit in spaces for landfilling. Hence, it is vital to look into a suitable food waste management method upon the issues. The application of Multi Criteria Decision Making (MCDM) is important in assisting the decision-making process by suggesting suitable food waste management treatment method. It helps to select shortlisted criteria that fulfill the requirements in line with the preferences and suggest on suitable treatment selection for decision. Analytical Hierarchy Process (AHP), which is one of the MCDM techniques, able to provide a rational decision-making framework by incorporating many relevant criteria and alternative that is support by scientific values of the suggestion. With the aid of the decision-making technique, food waste can be properly managed through suitable management treatment method and promotes on circular economy, reducing impacts towards the environment. From the results analyzed through MCDM, it is encouraged to practice on Anaerobic digestion (AD) treatment as it results in significant reduction of impact towards the environment. The use of AD treatment has significantly show contribution towards the environment. This study allows in showing on how food waste can be management properly in the suitable and preferred method that allows in the reduction of environment pollution
DESIGNING OUT WASTE FROM THE PRODUCTION OF A LEARNING TOWER THROUGH MATERIAL FLOW ANALYSIS
Malaysia's furniture manufacturing industry is made up of small and medium enterprises (SMEs), which contribute significantly to the country's economy. One major issue that these SMEs face is sustainable manufacturing: lowering throughputs and increasing production efficiencies. The study aims to improve the efficiency of producing a learning tower; a furniture product by an SME called Industerior Design by implementing material flow analysis (MFA) to monitor production throughputs. The MFA was used to compare two different learning tower designs (Design A and B). The most sustainable design was determined based on the MFA. A cause-and-effect analysis was also carried out using the Ishikawa fishbone diagram to identify potential causes of production inefficiencies. Both designs were proven to have the same processes involved and the same waste stream generated; however, Design A produces four learning towers from a single wood plank with 15.5% waste generated, while Design B produces only two towers with 44.6% waste generated. Of the waste generated by both designs, 60% from Design B was recyclable, while for Design A only 25% was reusable. Inefficiencies can be caused by a lack of skilled workers, a lack of or infrequent maintenance of equipment, or the design of the product itself. When the amount of recyclable waste that can be used for other future projects was considered, it was determined that Design B was more sustainable in the long run. MFA is thus thought to be a simple but powerful tool that can be easily implemented by SMEs in designing out waste from their products as the furniture industry moves toward more sustainable manufacturing and a more circular economy.
RELATIONSHIP BETWEEN LEVEL OF AWARENESS AND WILLINGNESS TO PARTICIPATE IN RECYCLING
Municipal solid waste is increasingly becoming a significant environmental challenge as a result of population growth and rapid development. Accordingly, environmental degradation such as air and water pollution as well as disease spread could happen. Recycling is the best approach to reduce environmental impacts from mismanagement of municipal solid waste. This study focuses on the recycling awareness level and willingness to participate in recycling practices as these two elements are the key factors affecting recycling behavior. Puchong suburban residential area is selected as the study area because most of the waste is generated in residential areas. A total of 424 residents were selected through multistage sampling, a combination of cluster random sampling and simple random sampling to participate in this research. The respondents are surveyed through a mixed-mode method to gather their perspectives towards recycling practices in daily lives. The questionnaires distributed consisted of three sections for socio-demographic background, recycling awareness and willingness to participate, respectively. The results discovered that the residents had a high awareness level of recycling with an overall mean of 4.08. Moreover, the residents were greatly willing to participate in recycling with an overall mean of 4.07. Besides, Kendall’s tau-b correlation, r = 0.451 and Spearman rank-order correlation, r = 0.600 showed that there was a moderate correlation between recycling awareness and willingness to participate. Therefore, to encourage the public’s participation and contribution towards recycling, local authorities shall continually take decisive actions to promote recycling awareness and disseminate recycling information. In addition, this research contributes to the knowledge of relationship between the two variables.
APPLICATION OF ARTIFICIAL NEURAL NETWORK FOR SOLID WASTE PROJECTION AND ENERGY CONTENT EVALUATION
Forecasts of the heterogeneous municipal solid waste (MSW) generation are vital for sustainable MSW management. Artificial neural network (ANN) models have been successfully demonstrated to predict complex MSW trends, but the negligence of the MSW’s heterogeneous characteristics hinders the further application of the predictions. This study aims to adopt robust ANN models coupling Bayesian hyperparameter optimization and uncertainty analysis to forecast the heterogeneous MSW generation in a country with further application in energy content evaluation. The impact of the hyperparameter optimization is illustrated by comparing the forecast uncertainties of ANN models using the Bayesian-optimized hyperparameters and default hyperparameters using ensemble forecasts. The relative standard deviations of the ensemble forecasts show that overfitting is more susceptible in the default models (11.1% – 44,400%) than in the Bayesian-optimized models (3.64% – 27.7%). By using the Bayesian-optimized models, Malaysia’s heterogeneous MSW generation is projected individually based on its physical composition. The total MSW generation in Malaysia is expected to grow by 12% from 2020 to 2030, with food waste as the dominant composition (44%). The energy content of the overall MSW is evaluated based on the lower calorific value of the forecasted MSW. The forecasted increase in food waste generation reduces the lower caloric value of Malaysia’s MSW below the lower limit to burn without supporting fuel (i.e., 6.5 MJ/kg). An alternative scenario where food waste is segregated from the overall MSW shows an increase in the lower calorific value from 5.874 MJ/kg to 10.31 MJ/kg. Without food waste segregation, the development of organic waste treatment facilities in Malaysia should be emphasized instead of incinerators. This study not only offers useful information for capacity planning of MSW treatment facilities using a data-driven approach, but it also broadens the scope for future related research by examining the application of the forecasted outcomes using ANN models.
APPLICATION OF MATERIAL FLOW ANALYSIS TO MUNICIPAL SOLID WASTE IN SRI LANKA SPECIAL FOCUS TO URBAN ENVIRONMENT
Understanding waste flow of a country is important to identify main problems associated with waste management and identify opportunities in material flow management. Tools such as material flow analysis (MFA) is widely used method in waste management studies, to provide comprehensive analysis of material movements, support for material characterization analysis to identify severity of the problem, to identify real root cause and propose suitable management methods. This paper presents application of MFA for municipal solid waste (MSW) management in nine provinces in Sri Lanka. The outcome includes the identification, quantification of the main input and output flows of the system in present context, from waste generation, collection, unaccounted and unidentified flows, material recovery and final disposal of MSW. Overall results show per capita waste generation in Sri Lanka stood at 0.43kg, whereas Western province represents that of 0.53kg. On the other hand, 30% of the MSW is collected by the local authorities (institutional set up which is responsible for collecting waste in the country) out of total waste generation, 42% is burnt and 24% burry at house hold level. Balance represents composting and reusing - repurposing at house hold level. Results of this study show the importance of further research in unaccounted and unidentified material flows goes with burying and burning at household level. This can cause more harm to environment and human health
Copyright (c) 2021 Proceedings of the World Conference on Waste Management
Application of Circular-Economy Concept to Pre-Consumer Apparel Waste Management in Sri Lanka
Sri Lanka is one of the major apparel manufacturers in South Asian region, which results to generate more pre-consumer apparel waste. Many of the past studies have shown that absence of acceptable waste management systems, to manage massive amounts of pre-consumer apparel waste generated has made the waste management issue complicated. In Sri Lanka, it is likely that 25% of apparel waste are reused and recycled while landfilling and incinerating the rest which have adverse environmental impacts. This ‘take, make, consume and discard’ principle is known as the basis of Linear Economy (LE) and due to the series of challenges and the underlying limitations of it, the concept of Circular Economy (CE) is considered as a solution for harmonising ambitions for economic growth and environmental protection. Lean Manufacturing, Green Supply Chain Management, Extended Producer Responsibility and 3R Concept are the waste management approaches that have been used to implement the concept of CE in pre-consumer apparel waste management. The aim of this research is to enhance the effective pre-consumer apparel waste management practices through CE concept. This paper will present implementation tools of aforementioned waste management concepts in order to implement the concept of CE effectively. Holistic, multiple case studies have been adopted as the research strategy under qualitative approach, accordingly 08 semi-structured interviews were conducted from four leading apparel manufacturing organisations in Sri Lanka. Through the study it was identified that Kaizen, Kanban, partnering with brands and suppliers into sustainable manufacturing and polluter pays principle are some of the implementation tools which needs to be implemented and further enhanced for the effective implementation of CE concept within the Sri Lankan context.
EVALUATION OF POTENTIAL APPLICATION OF INDUSTRIAL SYMBIOSIS
Most of the industries in Sri Lanka generate a considerable amount of waste which are either open dumped or disposed without due consideration of the environment and ecosystem. The haphazard disposal of the untreated waste is growing in to a major problem in the country due to high cost of treatment for industries, lack of infrastructure for industrial waste management, ineffective enforcement of environmental regulations and insufficient capacity for waste management of local authorities. The country has not a properly established waste treatment facilities for industrial waste. Industrial symbiosis, which is considered mainly by the reuse of waste from one company as raw material by another, has been applied globally with recognized environmental, economic, and social benefits. However, the potential for industrial symbiosis is not exhausted in existing cases, and there is still a wide range of opportunities for its application. This paper has identified necessary key steps required to develop a conceptual framework to implement industrial symbiosis for manufacturing sector. It has identified three main steps i.e identification of industrial symbiosis potential, network development stage, decision support tool.
By-products of the whelk processing industry as valuable source of bioactive peptides
The fish and shellfish industry processes 851,984 tonnes of fish per year worldwide. However, only 43% of that is consumed, and valuable proteins that are going to waste. Protein hydrolysates are widely used in food technology for their nutritional and functional properties. The goal of this project is to extract protein from the shellfish processing industry by-products and create protein hydrolysates that have marketable value. The waste was divided into two types: raw waste (R) and cooked waste (C). The proteins were extracted using the pH shift method at acid (A), neutral (N) and basic (B) pH, they were then quantified using the Bradford assay, for which R had the highest protein yield. Proteins were also qualified using reverse phase high-performance liquid chromatography (RP-HPLC) that showed that R has more hydrophilic proteins while the C protein showed more peaks in the hydrophobic phase. The Fourier-transform infrared spectroscopy (FTIR) indicated the presence of glutamine, tyrosine and serine in the extracted proteins. Extracted proteins were then hydrolyzed using Alcalase and α-Chymotrypsin and the degree of hydrolysis measured with a 2,4,6-Trinitrobenzene Sulfonic Acid (TNBS) assay. It was possible to obtain higher degrees of hydrolysis (DH) of using Alcalase. The hydrolysates were tested for antioxidant activity using the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free radical antioxidant assay. Alcalase hydrolysates showed to have an IC50 for the DPPH assay of 33.79±2.96 µg/mL, 13.92±1.57 µg/mL and 36.09±3.04 µg/mL, and α-Chymotrypsin hydrolysates 43.24±2.11 µg/mL, 81.18±4.07 µg/mL and 56.02±2.29 µg/mL for A, N and B protein, respectively. The IC50 results obtained are significantly lower than the ones described in other studies using the same enzymes or other marine species. This can indicate that more heterogenous mixtures of by-product can originate extracted proteins that when hydrolyzed lead to higher radical scavenging activity.
Sustainable Biochemistry and Biotechnology
Using a Baseline to Improve Accuracy of Waste Diversion Rate
As part of its new sustainability goal “Zero Waste”, General Motors aims to divert 90% of its total waste generation from landfills and incineration with or without energy recovery by 2025. To achieve this goal, it is necessary to determine the correct method to track the percentage of waste diverted over time, since it will be the key performance indicator (KPI) of the program. The most accepted method to calculate this KPI is by dividing the total amount of waste diverted from landfills and/or incinerators by the total amount of waste generated in a specific time period. This methodology presents a simple snapshot of the current performance and does not fully address the long-term performance. The new proposal aims to track performance over time using similar approach as defined in the revised edition of the Greenhouse Gas Protocol. The new methodology uses a baseline to track performance and determines the diversion rate by comparing the total nondiverted material against the baseline. This method has shown accurate percentage of diversion rate and improved the company’s data management since past data was used to calculate the baseline.
The Role of Government towards a Circular Economy in the Construction Industry: A Systematic Literature Review
A circular economy (CE) model provides an opportunity for the construction industry (CI) to keep the end-of-life materials in a closed loop with their maximum value while advocating the reduction of significant waste generation and natural resource extraction for the built environment. While previous studies in different geographical regions have been individually carried out on investigating the government engagement in the CE, no solitary study exists that holistically focus upon the role of government that steers the CI towards a CE. With this concern, the objectives of the current study are twofold. First, to investigate the roles through which the government contributes to implementing CE in the CI. Second, it outlines the potential research directions for future researchers to expand the domain under study. To achieve these objectives, a systematic literature review (SLR) was conducted based on the review protocol, Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A total of 125 articles available in four search engines from 2002 to 2020 were incorporated for both descriptive and content analysis. Most articles (19) were published in the year 2019, and China is the dominant country for publishing most of the articles in the area under study. The study found that the government influences the CE in the CI by playing four significant roles: regulating, subsidizing, encouraging and informing. Herein, the government should play these four roles jointly with the amalgamation of government agencies, research institutions and nongovernment associations. The article concludes by outlining the future research priorities to advance the understanding in the domain under study. The value of the study is that it explores an overlooked area in the existing literature while providing a direction for the CI practitioners to understand the government role in paving the path to a CE.
Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)
Organic Waste Composting: A Resource Recovery Approach towards Sustainable Environment
Organic waste (including kitchen, garden/lawn, and agricultural waste) were subject to composting through static pile and soil pit composting techniques to determine the best method for managing the organic fraction of Municipal Solid Waste (MSW). These conventional methods were used with some innovations (by using soil as seed compost and aeration assembly) to increase the efficiency while keeping the process cost effective. Quantitative parameter analysis of initial feedstocks such as weight, moisture content (MC) and bulk density (BD) were measured before setting up each experiment. Temperature variation was monitored on a daily basis and measurement of CO2 emission on weekly basis. Moreover, mixing of feedstock for aeration and applying water for optimum moisture content were also subject to weekly activities. Final compost from each experiment was analyzed against physical and chemical parameters such as colour, MC, BD, water holding capacity, pH and electrical conductivity. Aerobic soil pit showed better results among other composting techniques with with BD of 530±0.01 kg/m3 , MC 37.40±0.26 %, water holding capacity 94±0.45 %, pH 8.00±0.10 and electrical conductivity 1.06±14.42 dS/m. Based on the experiment’s results, there were two conclusions drawn, first the application of soil proved to be very helpful as seed compost in a static pile showing good results. Secondly, soil pit composting with modification of passive aeration also proved it as a potential technique to manage organic waste.
Copyright (c) 2019 Proceedings of the World Conference on Waste Management
A Study on Challenges for Adoption of Reverse Vending Machine: A Case of North Bengaluru, India
India will be producing 80-85 MT of Solid waste by 2030. Given the alarming quantity it is imperative to bring in methods which will alleviate the problem especially the plastic waste. One of the products which helps in effective disposal of plastics is the Reverse Vending Machine (RVM). An RVM is a device which accepts bar coded plastic bottles and returns digital cash or redeemable coupons. The field study and literature show that reverse vending machine is not used extensively. This study attempts to explore the challenges for adoption of eco-friendly products like RVM. A conceptual model was built using the variables identified through literature review. The variables identified included awareness, willingness, incentives, convenience and involvement. A survey was designed and data was collected from 246 citizens to understand their views. Structural Equation Modelling was used to test conceptual model. The results emphatically show that willingness to adopt RVM was influenced by factors of involvement, convenience, awareness and incentives in that order. It is also intuitive that when involvement is high then there is an attempt to become aware and adopt eco-friendly methods which is reiterated by the results. Hence citizens have to get involved either by their own interest or by enforcing through legislation and policies to use RVM. The study concludes by recommending more policies and strategies like “bottle bill”, “European Union Plastic Strategy” and Recycle Refund Systems to be mandated across the world to encourage citizens to use methods which will keep our environment plastic free.
Evaluation of PM Emissions of a Diesel Engine Fueled with Waste Cooking Oil Biodiesel: A Systematic Review
The Navigation Guide developed by Johnson et al was used to conduct a robust systematic review of six experimental intervention studies comparing particulate matter (PM) emissions from heavy-duty diesel engines using waste cooking oil biodiesel versus conventional petroleum diesel fuel. Waste cooking oil biodiesel is thought to be a more sustainably sourced alternative to its fossil fuel counterpart and can aid in reducing cooking oil waste streams. The Navigation Guide systematic review methodology tool was applied to analyse the hypothesized question: Does the replacement of petroleum diesel with waste cooking oil biodiesel reduce hazardous PM emissions in heavy duty vehicles? The study question was specified, evidence was selected and the quality and strength of the overall evidence was assessed for both individual studies and across the body of studies. Precise criteria and protocols were developed and followed throughout the review process to ensure that a thorough evaluation of all data was completed. All six studies that met the review inclusion criteria utilized six-cylinder direct injection engines. Although the PM emissions were measured differently across the exposure continuum, there was an overall PM emission reduction of 28% across the studies when petroleum diesel was substituted with waste cooking oil biodiesel. The overall risk of bias across the studies was determined to be „low‟. Based on the application of the Navigation guide methodology, it was found that the strength of the evidence provided was „sufficient‟ to suggest an association between waste cooking oil biodiesel and PM emission reductions
Origins of Construction and Demolition Waste Generation in the Sri Lankan Construction Industry
C&D waste management is an area where attention needs to be paid for as the construction industry is considered to be one of the key solid waste generators. Mainly, C&D waste get generated through the new construction, renovation of buildings, and through the demolition of buildings and structures. Hence, it is necessary to manage the C&D waste. In order to manage the C&D waste, it is necessary to identify the types and origins of waste. Thus, the aim of the paper is to identify the types of C&D waste and their origins of generation. This paper critically reviews secondary data and findings of eight case studies under the qualitative approach. Through the case study findings, it was evident that plywood, concrete, cement, steel offcuts, blocks bricks, sand, soil, wood, polythene and food waste as the main types of C&D waste in Sri Lankan construction sites. Further, design changes, transport, human mistakes, quality of works, client changes and mismatches in required materials are identified as the key origins for C&D waste generation in Sri Lankan construction sites. Therefore, to achieve the aim of the paper, types of C&D waste materials and origins of C&D waste generation were identified.
Identifying Hidden Factors Affecting Household Solid Waste Generation for an Effective Waste Management System
Current urbanization, rapid economic growth and changes in the consumption pattern are burning issues faced by the developing countries on solid waste management. Proper solid waste management should be implemented with the urbanization in order to manage the households’ waste generation. There should be proper solid waste management strategies and techniques within the micro level. Identifying households’ hidden factors affecting towards waste generation in households led the foundation to develop an accurate waste management system. The study was administrated in the Colombo district using 335 households taken from Maharagama Urban Council and Kotikawatta-Mulleriyawa Pradeshiya Sabha. Solid waste generation in the household based on the low, middle and high income level was 0.12 Kg/person/day, 0.17 Kg/person/day and 0.25 Kg/person/day. The study found that hidden factors for waste generation in households were family consumption pattern, family background, nature of the waste collection and ways of treating waste. Recognizing the opportunities and challenges within the area provides a clear path for waste management.