Forecasting municipal solid plastic waste generation and management policy using system dynamics: a case study of Khulna City in Bangladesh.

A comprehensive analysis of municipal solid plastic waste (MSPW) management while emphasizing plastic pollution severity in coastal cities around the world is mandatory to alleviate the augmenting plastic waste footprint in nature. Thus, decision-makers' persuasion for numerous management solutions of MSPW flow-control can be met through meditative systematic strategies at the regional level. To forecast solutions focused on systematic policies, an agent-based system dynamics (ASD) model has been developed and simulated from 2023 to 2040 while considering significant knit parameters for MSPW management of Khulna City in Bangladesh. Baseline simulation results show that per-capita plastic waste generation will increase to 11.6 kg by 2040 from 8.92 kg in 2023. Eventually, the landfilled quantity of plastic waste has accumulated to 70,000 tons within 18 years. Moreover, the riverine discharge has increased to 834 tons in 2040 from a baseline quantity of 512 tons in 2023. So the plastic waste footprint index (PWFI) value rises to 24 by 2040. Furthermore, the absence of technological initiatives is responsible for the logarithmic rise of non-recyclable plastic waste to 1.35*1000=1350 tons. Finally, two consecutive policy scenarios with baseline factors such as controlled riverine discharge, increased collection and separation of plastic waste, expansion of recycle business, and locally achievable plastic conversion technologies have been simulated. Therefore, policy 2, with 69% conversion, 80% source separation, and 50% riverine discharge reduction of MSPW, has been found adequate from a sustainability perspective with the lowest PWFI ranges of 3.97 to 1.07 alongside a per-capita MSPW generation of 7.63 to 10 kg from 2023 till 2040.

Unwrapping nutrition: Exploring the impact of hospital food and beverage packaging on plate waste/intake in older people.

Food and beverage packaging is increasingly used in hospital food service provision. Previous research has identified that the packaging used in New South Wales hospitals can be difficult to open by older adults. As older adults experience high rates of malnutrition, it is important to understand the effects of packaging on actual consumption of food and fluids. The aim of this study was to explore the impact of hospital food and beverage packaging on dietary intakes of 62 independently living older people (65 years and over) in a university simulated hospital ward in NSW, Australia. Participants were allocated to either a breakfast and snack meal or a lunch and snack meal on two occasions one week apart. Meals were served in a shared ward environment and each participant experienced a 'sealed' and 'pre-opened' meal and snack condition. The nutritional status of participants was measured using the Mini Nutritional Assessment - Short Form (MNA®-SF) and intake was estimated through an aggregated plate waste method. Overall findings were not significant for dietary intakes and the 'sealed' versus 'pre-opened' conditions. However, for the seven participants classified by the MNA®-SF as 'at risk' of malnutrition, packaging impeded intake for breakfast (η2 = -0.34) and the high protein snack (cheese and biscuits) (η2 = -0.24) meals. This finding has implications for the provision of packaged high protein snacks (cheese portions) and breakfast meals for the older inpatient. Further research is required for nutritionally compromised and frail older people in the hospital environment to investigate the impact of packaging on food and beverage consumption in detail.

Utilization of ZeoliticWaste in Alkali-Activated Biomass Bottom Ash Blends.

This study aims to investigate the effects of ammonium-bearing zeolitic waste (FCC) on alkali-activated biomass bottom ash (BBA). FCC was obtained from the oil-cracking process in petroleum plants. In this study, two types of production waste were used: biomass bottom ash and ammonium-bearing zeolitic waste. These binary alkali-activated FCC/BBA blends were investigated using X-ray diffraction (XRD), Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) methods. The compressive strength of the hardened samples was evaluated. The results show that the samples made from alkali-activated BBA biomass bottom ash had low (8.5 MPa) compressive strength, which could be explained with low reactive BBA and insufficient quantities of silicon and aluminum compounds. The reactivity of BBA was improved with incorporating zeolitic waste as an aluminosilicate material. This zeolitic waste was first used for ammonium sorption; then, it was incorporated in alkali-activated samples. Additional amounts of hydrated products formed, such as calcium silicate hydrate, calcium aluminum silicate hydrate and calcium sodium aluminum silicate hydrate. The silicon and aluminum compound, which varied in zeolitic waste, changed the mineral composition and microstructure of alkali-activated binder systems. NH4Cl, which was incorporated in the zeolitic waste, did not negatively affect the compressive strength of the alkali-activated BBA samples. This investigation proved that waste materials can be reused by producing alkali-activated binders.

Achieving the Sustainable Development Goal 06 in Brazil: the universal access to sanitation as a possible mission.

Sanitation (which includes national public policies for drinking water, sewage services and waste management) is precarious in Brazil and therefore poses a challenge to a range of actors. Poor sanitation impacts public health, education, the environment, and daily life. Globally, it emits increasing greenhouse gases. Universalization of any major public service appears difficult, if not impossible; however, Brazil's program to universalize access to electricity proves the opposite, as will be shown in this paper. By describing the successful implementation of electricity for everyone, we show that planned public efforts, coordinated with private initiatives and local communities, have worked, and the same can be achieved for the sanitation sector. An overview of all sectors that touch on sanitation and emissions is also provided, highlighting the challenges and possibilities for infrastructure projects.

Variability of Greek dental solid waste production by different dentist groups.

The objective of this work was to compare the composition and production rate of Greek dental solid waste (DSW) produced by three dentist groups of Xanthi, Greece, defined according to the country of their dental education/training: (1) dentists educated in Greece and other European Union (EU) countries, (2) dentists educated in Turkey, and (3) dentists educated in former Soviet Union and repatriated to Greece. All DSW produced by a total of 2542 patients in 20 dental practices from Xanthi, Greece, was collected, manually separated, and weighed over a period of four working weeks and classified according to Greek regulations. Production data below are presented as average (standard deviation in parenthesis). The average unit production rates of total DSW were 415(303) and 51.2(19.1) g/patient/day for dentists educated in Greece and other EU countries, 365(160) and 64.0(21.7) g/patient/day for dentists educated in Turkey, and 302(349) and 54.3(46.8) g/patient/day for dentists educated in former Soviet Union. Daily DSW production was correlated with daily number of patients and regression correlations were produced. Statistical analysis using the Kruskal-Wallis non-parametric test was conducted to compare DSW production medians by the three dentist groups. Dentists educated in Turkey had statistically higher median patient-based unit production rates at α = 0.05 for total dental, total hazardous, total infectious, total toxic and domestic-type waste, compared to the other dentist groups.

Analysis and forecasting of municipal solid waste in Nankana City using geo-spatial techniques.

The objective of this study was to analyze and forecast municipal solid waste (MSW) in Nankana City (NC), District Nankana, Province of Punjab, Pakistan. The study is based on primary data acquired through a questionnaire, Global Positioning System (GPS), and direct waste sampling and analysis. Inverse distance weighting (IDW) technique was applied to geo-visualize the spatial trend of MSW generation. Analysis revealed that the total MSW generated was 12,419,636 kg/annum (12,419.64 t) or 34,026.4 kg/day (34.03 t), or 0.46 kg/capita/day (kg/cap/day). The average wastes generated per day by studied households, clinics, hospitals, and hotels were 3, 7.5, 20, and 15 kg, respectively. The residential sector was the top producer with 95.5% (32,511 kg/day) followed by commercial sector 1.9% (665 kg/day). On average, high-income and low-income households were generating waste of 4.2 kg/household/day (kg/hh/day) and 1.7 kg/hh/day, respectively. Similarly, large-size families were generating more (4.4 kg/hh/day) waste than small-size families (1.8 kg/hh/day). The physical constituents of MSW generated in the study area with a population of about 70,000 included paper (7%); compostable matter (61%); plastics (9%); fine earth, ashes, ceramics, and stones (20.4%); and others (2.6%).The spatial trend of MSW generation varies; city center has a high rate of generation and towards periphery generation lowers. Based on the current population growth and MSW generation rate, NC is expected to generate 2.8 times more waste by the year 2050.This is imperative to develop a proper solid waste management plan to reduce the risk of environmental degradation and protect human health. This study provides insights into MSW generation rate, physical composition, and forecasting which are vital in its management strategies.

Multi-criteria analysis for municipal solid waste management in a Brazilian metropolitan area.

The decision-making process involved in municipal solid waste management (MSWM) must consider more than just financial aspects, which makes it a difficult task in developing countries. The Recife Metropolitan Region (RMR) in the Northeast of Brazil faces a MSWM problem that has been ongoing since the 1970s, with no common solution. In order to direct short-term solutions, three MSWM alternatives were outlined for the RMR, considering the current and future situations, the time and cost involved and social/environmental criteria. A multi-criteria approach, based on the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE), was proposed to rank these alternatives. The alternative that included two private landfill sites and seven transfer, sorting and composting stations was confirmed as the most suitable and stable option for short-term MSWM, considering the two scenarios for the criteria weights. Sensitivity analysis was also performed to support the robustness of the results. The implementation of separate collections would minimize the amount of waste buried, while maximizing the useful life of landfill sites and increasing the timeframe of the alternative. Overall, the multi-criteria analysis was helpful and accurate during the alternative selection process, considering the similarities and restrictions of each option, which can lead to difficulties during the decision-making process.

Development of models for prediction of the energy content of disposed MSW from an unsecured landfill.

This research was undertaken to estimate the energy potential of municipal solid waste (MSW) disposed over the past 15 years in an unsecured landfill located in Okhla, Delhi, India. The research collected a total of 98 samples from various depths and locations, which were analyzed for physico-chemical characterization. Multiple regression models for estimating the energy content of the disposed MSW were developed to predict average gross calorific value (GCV) and net calorific value (NCV). Forward entry regression was applied to identify the variables that contributed significantly to the regression. Thus, 4-parametric models and 2-parametric models were developed for predicting both average GCV and NCV of the disposed MSW. The developed models gave a reasonably good prediction of the energy content of MSW. Both the models gave low values of average absolute relative error and high values of correlation coefficient. It was found that the 2-parametric models exhibited nearly the same prediction ability with less measurable dimensions as the 4-parametric models. These models are unique and the research is a pioneering effort since apart from being the only models based on physico-chemical characteristics of disposed MSW to be reported, they also incorporate the effect of the depth of waste as an independent variable. The developed models can be used to predict calorific values of disposed MSW having similar characteristics in other landfill sites in India and abroad.

Evaluation of two different alternatives of energy recovery from municipal solid waste in Brazil.

Brazil has a large population with a high waste generation. The municipal solid waste (MSW) generated is deposited mainly in landfills. However, a considerable fraction of the waste is still improperly disposed of in dumpsters. In order to overcome this inadequate deposition, it is necessary to seek alternative routes. Between these alternatives, it is possible to quote gasification and incineration. The objective of this study is to compare, from an energetic and economic point of view, these technologies, aiming at their possible implementation in Brazilian cities. A total of two configurations were evaluated: (i) waste incineration with energy recovery and electricity production in a steam cycle; and (ii) waste gasification, where the syngas produced is used as fuel in a boiler of a steam cycle for electricity production. Simulations were performed assuming the same amount of available waste for both configurations, with a composition corresponding to the MSW from Santo André, Brazil. The thermal efficiencies of the gasification and incineration configurations were 19.3% and 25.1%, respectively. The difference in the efficiencies was caused by the irreversibilities associated with the gasification process, and the additional electricity consumption in the waste treatment step. The economic analysis presented a cost of electrical energy produced of 0.113 (US$ kWh-1) and 0.139 (US$ kWh-1) for the incineration and gasification plants respectively.

Determining the amount of waste plastics in the feed of Austrian waste-to-energy facilities.

Although thermal recovery of waste plastics is widely practiced in many European countries, reliable information on the amount of waste plastics in the feed of waste-to-energy plants is rare. In most cases the amount of plastics present in commingled waste, such as municipal solid waste, commercial, or industrial waste, is estimated based on a few waste sorting campaigns, which are of limited significance with regard to the characterisation of plastic flows. In the present study, an alternative approach, the so-called Balance Method, is used to determine the total amount of plastics thermally recovered in Austria's waste incineration facilities in 2014. The results indicate that the plastics content in the waste feed may vary considerably among different plants but also over time. Monthly averages determined range between 8 and 26 wt% of waste plastics. The study reveals an average waste plastics content in the feed of Austria's waste-to-energy plants of 16.5 wt%, which is considerably above findings from sorting campaigns conducted in Austria. In total, about 385 kt of waste plastics were thermally recovered in all Austrian waste-to-energy plants in 2014, which equals to 45 kg plastics cap-1. In addition, the amount of plastics co-combusted in industrial plants yields a total thermal utilisation rate of 70 kg cap-1 a-1 for Austria. This is significantly above published rates, for example, in Germany reported rates for 2013 are in the range of only 40 kg of waste plastics combusted per capita.

Support for designing waste sorting systems: A mini review.

This article presents a mini review of research aimed at understanding material recovery from municipal solid waste. It focuses on two areas, waste sorting behaviour and collection systems, so that research on the link between these areas could be identified and evaluated. The main results presented and the methods used in the articles are categorised and appraised. The mini review reveals that most of the work that offered design guidelines for waste management systems was based on optimising technical aspects only. In contrast, most of the work that focused on user involvement did not consider developing the technical aspects of the system, but was limited to studies of user behaviour. The only clear consensus among the articles that link user involvement with the technical system is that convenient waste collection infrastructure is crucial for supporting source separation. This mini review reveals that even though the connection between sorting behaviour and technical infrastructure has been explored and described in some articles, there is still a gap when using this knowledge to design waste sorting systems. Future research in this field would benefit from being multidisciplinary and from using complementary methods, so that holistic solutions for material recirculation can be identified. It would be beneficial to actively involve users when developing sorting infrastructures, to be sure to provide a waste management system that will be properly used by them.

Assessment of the municipal solid waste management system in Accra, Ghana: A 'Wasteaware' benchmark indicator approach.

This article assesses the performance of the city of Accra, Ghana, in municipal solid waste management as defined by the integrated sustainable waste management framework. The article reports on a participatory process to socialise the Wasteaware benchmark indicators and apply them to an upgraded set of data and information. The process has engaged 24 key stakeholders for 9 months, to diagram the flow of materials and benchmark three physical components and three governance aspects of the city's municipal solid waste management system. The results indicate that Accra is well below some other lower middle-income cities regarding sustainable modernisation of solid waste services. Collection coverage and capture of 75% and 53%, respectively, are a disappointing result, despite (or perhaps because of) 20 years of formal private sector involvement in service delivery. A total of 62% of municipal solid waste continues to be disposed of in controlled landfills and the reported recycling rate of 5% indicates both a lack of good measurement and a lack of interest in diverting waste from disposal. Drains, illegal dumps and beaches are choked with discarded bottles and plastic packaging. The quality of collection, disposal and recycling score between low and medium on the Wasteaware indicators, and the scores for user inclusivity, financial sustainability and local institutional coherence are low. The analysis suggests that waste and recycling would improve through greater provider inclusivity, especially the recognition and integration of the informal sector, and interventions that respond to user needs for more inclusive decision-making.

Forecasting municipal solid waste generation using prognostic tools and regression analysis.

For an adequate planning of waste management systems the accurate forecast of waste generation is an essential step, since various factors can affect waste trends. The application of predictive and prognosis models are useful tools, as reliable support for decision making processes. In this paper some indicators such as: number of residents, population age, urban life expectancy, total municipal solid waste were used as input variables in prognostic models in order to predict the amount of solid waste fractions. We applied Waste Prognostic Tool, regression analysis and time series analysis to forecast municipal solid waste generation and composition by considering the Iasi Romania case study. Regression equations were determined for six solid waste fractions (paper, plastic, metal, glass, biodegradable and other waste). Accuracy Measures were calculated and the results showed that S-curve trend model is the most suitable for municipal solid waste (MSW) prediction.

Transport of hydraulic fracturing waste from Pennsylvania wells: A county-level analysis of road use and associated road repair costs.

Pennsylvania's rapid unconventional oil and gas (UOG) development-from a single well in 2004 to more than 6700 wells in 2013-has dramatically increased UOG waste transport by heavy trucks. This study quantified the amount of UOG waste and the distance it traveled between wells and disposal facilities on each type of road in each county between July 2010 and December 2013. In addition, the study estimated the associated financial costs to each county's road infrastructure over that period. We found that UOG wells produced a median wastewater volume of 1294 m(3) and a median of 89,267 kg of solid waste. The median number of waste-transport truck trips per well was 122. UOG wells existed in 38 Pennsylvania counties, but we estimated trucks transporting well waste traveled through 132 counties, including counties in West Virginia, Ohio, and New York. Median travel distance varied by disposal type, from 106 km to centralized treatment facilities up to 237 km to injection wells. Local roads experienced the greatest amount of truck traffic and associated costs ($1.1-6.5 M) and interstates, the least ($0.3-1.6 M). Counties with oil and gas development experienced the most truck traffic and incurred the highest associated roadway costs. However, many counties outside the active development area also incurred roadway repair costs, highlighting the extension of UOG development's spatial footprint beyond the active development area. An online data visualization tool is available here: www.nicholasinstitute.duke.edu/transportation-of-hydraulic-fracturing-waste.

Greenhouse gas emissions from solid waste in Beijing: The rising trend and the mitigation effects by management improvements.

Disposal of solid waste poses great challenges to city managements. Changes in solid waste composition and disposal methods, along with urbanisation, can certainly affect greenhouse gas emissions from municipal solid waste. In this study, we analysed the changes in the generation, composition and management of municipal solid waste in Beijing. The changes of greenhouse gas emissions from municipal solid waste management were thereafter calculated. The impacts of municipal solid waste management improvements on greenhouse gas emissions and the mitigation effects of treatment techniques of greenhouse gas were also analysed. Municipal solid waste generation in Beijing has increased, and food waste has constituted the most substantial component of municipal solid waste over the past decade. Since the first half of 1950s, greenhouse gas emission has increased from 6 CO2-eq Gg y(-1)to approximately 200 CO2-eq Gg y(-1)in the early 1990s and 2145 CO2-eq Gg y(-1)in 2013. Landfill gas flaring, landfill gas utilisation and energy recovery in incineration are three techniques of the after-emission treatments in municipal solid waste management. The scenario analysis showed that three techniques might reduce greenhouse gas emissions by 22.7%, 4.5% and 9.8%, respectively. In the future, if waste disposal can achieve a ratio of 4:3:3 by landfill, composting and incineration with the proposed after-emission treatments, as stipulated by the Beijing Municipal Waste Management Act, greenhouse gas emissions from municipal solid waste will decrease by 41%.

Municipal solid waste management in Tehran: Changes during the last 5 years.

The situation of waste management in Tehran was a typical example of it in developing countries. The amount of municipal solid waste has been increasing and the city has depended on landfill for municipal solid waste management. However, in recent years, various measures have been taken by the city, such as collecting recyclables at the source and increasing the capacity of waste-processing facilities. As a result, significant changes in the waste stream are starting to occur. This study investigated the nature of, and reasons for, the marked changes in the waste stream from 2008 to 2012 by analysing the municipal solid waste statistics published by the Tehran Waste Management Organization in 2013 and survey data on the physical composition of the municipal solid waste. The following trends were identified: Although the generation of municipal solid waste increased by 10% during the 5-year period, the amount of waste directly disposed of to landfill halved and resource recovery almost doubled. An increase in the capacity of a waste-processing facility contributed significantly to these changes. The biodegradable fraction going to landfill was estimated by using the quantity and the composition of each input to the landfill. The estimated result in 2012 decreased to 49% of its value in 2008.

Construction and demolition waste generation rates for high-rise buildings in Malaysia.

Construction and demolition waste continues to sharply increase in step with the economic growth of less developed countries. Though the construction industry is large, it is composed of small firms with individual waste management practices, often leading to the deleterious environmental outcomes. Quantifying construction and demolition waste generation allows policy makers and stakeholders to understand the true internal and external costs of construction, providing a necessary foundation for waste management planning that may overcome deleterious environmental outcomes and may be both economically and environmentally optimal. This study offers a theoretical method for estimating the construction and demolition project waste generation rate by utilising available data, including waste disposal truck size and number, and waste volume and composition. This method is proposed as a less burdensome and more broadly applicable alternative, in contrast to waste estimation by on-site hand sorting and weighing. The developed method is applied to 11 projects across Malaysia as the case study. This study quantifies waste generation rate and illustrates the construction method in influencing the waste generation rate, estimating that the conventional construction method has a waste generation rate of 9.88 t 100 m-2, the mixed-construction method has a waste generation rate of 3.29 t 100 m-2, and demolition projects have a waste generation rate of 104.28 t 100 m-2.

Search for a new economic optimum in the management of household waste in Tiaret city (western Algeria).

In household waste matters, the objective is always to conceive an optimal integrated system of management, where the terms 'optimal' and 'integrated' refer generally to a combination between the waste and the techniques of treatment, valorization and elimination, which often aim at the lowest possible cost. The management optimization of household waste using operational methodologies has not yet been applied in any Algerian district. We proposed an optimization of the valorization of household waste in Tiaret city in order to lower the total management cost. The methodology is modelled by non-linear mathematical equations using 28 variables of decision and aims to assign optimally the seven components of household waste (i.e. plastic, cardboard paper, glass, metals, textiles, organic matter and others) among four centres of treatment [i.e. waste to energy (WTE) or incineration, composting (CM), anaerobic digestion (ANB) or methanization and landfilling (LF)]. The analysis of the obtained results shows that the variation of total cost is mainly due to the assignment of waste among the treatment centres and that certain treatment cannot be applied to household waste in Tiaret city. On the other hand, certain techniques of valorization have been favoured by the optimization. In this work, four scenarios have been proposed to optimize the system cost, where the modelling shows that the mixed scenario (the three treatment centres CM, ANB, LF) suggests a better combination of technologies of waste treatment, with an optimal solution for the system (cost and profit).

Quantification of Food Waste Disposal in the United States: A Meta-Analysis.

Food waste has major consequences for social, nutritional, economic, and environmental issues, and yet the amount of food waste disposed in the U.S. has not been accurately quantified. We introduce the transparent and repeatable methods of meta-analysis and systematic reviewing to determine how much food is discarded in the U.S., and to determine if specific factors drive increased disposal. The aggregate proportion of food waste in U.S. municipal solid waste from 1995 to 2013 was found to be 0.147 (95% CI 0.137-0.157) of total disposed waste, which is lower than that estimated by U.S. Environmental Protection Agency for the same period (0.176). The proportion of food waste increased significantly with time, with the western U.S. region having consistently and significantly higher proportions of food waste than other regions. There were no significant differences in food waste between rural and urban samples, or between commercial/institutional and residential samples. The aggregate disposal rate for food waste was 0.615 pounds (0.279 kg) (95% CI 0.565-0.664) of food waste disposed per person per day, which equates to over 35.5 million tons (32.2 million tonnes) of food waste disposed annually in the U.S.

Factors determining waste generation in Spanish towns and cities.

This paper analyzes the generation and composition of municipal solid waste in Spanish towns and cities with more than 5000 inhabitants, which altogether account for 87% of the Spanish population. To do so, the total composition and generation of municipal solid waste fractions were obtained from 135 towns and cities. Homogeneity tests revealed heterogeneity in the proportions of municipal solid waste fractions from one city to another. Statistical analyses identified significant differences in the generation of glass in cities of different sizes and in the generation of all fractions depending on the hydrographic area. Finally, linear regression models and residuals analysis were applied to analyze the effect of different demographic, geographic, and socioeconomic variables on the generation of waste fractions. The conclusions show that more densely populated towns, a hydrographic area, and cities with over 50,000 inhabitants have higher waste generation rates, while certain socioeconomic variables (people/car) decrease that generation. Other socioeconomic variables (foreigners and unemployment) show a positive and null influence on that waste generation, respectively.