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.

Assessment of municipal solid waste from households in Khulna city of Bangladesh.

Waste management is a major concern for both developed and developing countries, with a particular focus on household waste because it makes up a significant proportion of municipal waste. The aim of this study is to assess the state of solid waste management practice in Khulna, as well as to characterize and quantify municipal solid waste as a step toward effective management. To collect information on the existing waste management methods, structured questionnaires were used to conduct surveys of household residents. In this study, whole wards (31 wards) of Khulna City Corporation (KCC) were clustered in 9 groups and selected one ward from each group. To analyze household waste, 75 households from each ward were selected and collected waste for 7 days. The selected household was categorized into five different socioeconomic strata such as low-income, lower-middle-income, middle-income, higher-middle-income and higher-income families. Besides, the assessment was carried out on the production and characterization of household waste that was produced in KCC. The waste samples were quantified, separated and characterized in the laboratory. Results reveal that biodegradable waste is the most prominent type and its percentage is about 81 %. The amount of waste production is positively correlated with income level. The waste generation rate of households for high-income families was 0.652 kg/cap/day while this rate got almost half for a low-income family and its value is o.312 kg/cap/day. Source separation of waste plays a vital role to reduce plastic leakage to the SDP. The result shows the proportion of plastic in mixed waste and source-separated waste after sorting by the waste collector was 4.04 % and 2.99 %, respectively. Survey results show that 42.96 % of respondents think that the source-separated waste should be collected during the period of 12pm to 02pm. A proposed management process was developed for household waste based on the output of this study.

Application of system dynamics model for municipal solid waste management in Khulna city of Bangladesh.

The long term municipal solid wastes (MSW) management plan of Khulna city has to be focused on the Bangladesh Delta Plan 2100. In most developing countries, conventional system of MSW management approach has been found inadequate due to complex nature of MSW. This study presents a system dynamics (SD) model to predict generation, collection, treatment and landfill capacity of MSW until the year of 2050 to analyze the necessity for MSW management for the coastal city of Khulna, Bangladesh. Simulation results show that MSW generation increases from 168 thousand tons in year 2020 to 1.2 million tons with a per capita generation from 0.117 tons to 0.561 tons by year 2050. The total fund required for collection and landfill capacity also increases, while treatment capacity decreases over time, resulting a piling up of massive amount of uncleared MSW of 10.3 million tons in year 2050 from 152 thousand tons in year 2020. The uncleared and untreated MSW, composite index and public concern increases with time in an exponential nature for the projection period of next thirty years. The population in this model is considered as the only linear growth factor which increases from 1.5 million in year 2020 to 2.24 million by year 2050. The developed SD model also shows that the policy of only to increase collection capacity with the increased allocation of budget is not adequate for improving environmental sustainability, rather an increase of budget is essential for developing MSW treatment facility. In this study, validation methods including behavior sensitivity, data sensitivity and dimensional consistency in extreme condition has been performed to validate the model. The outcome of this SD model can be used as a dynamic testing module for MSW management policy analysis and strategic measures that can be implemented effectively in the context of developing counties.

Construction and evaluation of simulated pilot scale landfill lysimeter in Bangladesh.

This research concentrates the design, construction and evaluation of simulated pilot scale landfill lysimeter at KUET campus, Khulna, Bangladesh. Both the aerobic and anaerobic conditions having a base liner and two different types of cap liner were simulated. After the design of a reference cell, the construction of landfill lysimeter was started in January 2008 and completed in July 2008. In all construction process locally available civil construction materials were used. The municipal solid waste (MSW) of 2800-2985 kg having the total volume of 2.80 m(3) (height 1.6 m) and moisture content of 65% was deposited in each lysimeter by applying required compaction energy. In contrast, both the composition in terms of methane (CH(4)), carbon dioxide (CO(2)) and oxygen (O(2)) as well as the flow rate of landfill gas (LFG) generated from MSW in landfill lysimeter were measured and varied significantly in relation to the variation of lysimeter operational condition. Moreover, anaerobic lysimeter-C shows the highest composition of LFG in compare to the anaerobic lysimeter-B due to the providing of lower compaction of cap liner in anaerobic lysimeter-C. Here, it is interesting to note that in absence of compacted clay liner (CCL) and hence percolation of rainwater that facilitates rapid degradation of MSW in aerobic lysimeter-A has resulted in the highest settlement than that of anaerobic landfill lysimeter-B and C. Moreover, in case of anaerobic lysimeter-B and C, the leachate generation was lower than that of aerobic lysimeter-A due to the providing of cap liner in anaerobic lysimeter-B and C, played an important role to reduce the percolation of rainwater. The study also reveals that the leachate pollution index (LPI) has decreased in relation to the increasing of elapsed period as well as the LPI for collection system of aerobic lysimeter-A was higher than that of the collection system of anaerobic lysimeter-B and C. Finally, it can be depicted that LPI for lysimeter was significantly high and proper treatment will be necessary before discharging the lysimeter leachate into the water bodies.

Characterization and tropical seasonal variation of leachate: results from landfill lysimeter studied.

This study aims to characterize the leachate and to investigate the tropical climatic influence on leachate characteristics of lysimeter studies under different seasonal variations at KUET campus, Bangladesh. Three different situations of landfill were considered here as well as both the open dump lysimeter-A having a base liner and sanitary landfill lysimeter-B and C at two different types of cap liner were simulated. The leachate characteristics, leachate generation and climatic influence parameter had been continually monitored since June 2008 to May 2010, these periods cover both the dry and rainy season. The leachate generation had followed the rainfall pattern and the open dump lysimeter-A without top cover was recorded to have highest leachate generation. Moreover, the open dump lysimeter-A had lower total kjeldahl nitrogen (TKN), ammonia nitrogen (NH(4)-N) and TKN load, while both the COD concentration and load was higher compared with sanitary landfill lysimeter-B and C. In addition, sanitary landfill lysimeter-B, not only had lowest leachate generation, but also produces reasonable low COD concentration and load compared with open dump lysimeter-A. Result reveals that lysimeter operational mode had direct effect on leachate quality. Finally, it can be concluded that the knowledge of leachate quality will be useful in planning and providing remedial measures of proper liner system in sanitary landfill design and leachate treatment.