Municipal Solid Waste Samples Research Articles

Characterization of Municipal Solid Waste Based on Seasonal Diversity as Energy Potential Materials

Abstract Interrelated problems related to resource availability and population growth rates, such as energy demand and waste generation, have become pressing global concerns. Municipal Solid Waste (MSW) poses a significant challenge due to its impact on society and the environment, including the associated hazards and threats. This study was conducted at the Piyungan Integrated Santary Landfill (TPST Piyungan) in Yogyakarta, Indonesia, from June to November 2022. The annual waste generation in the city is 586,267.37 tons per year in 2021, with a daily per capita waste generation rate of 0.43 kg/person. Two types of MSW samples were collected during the dry and rainy season to assess their composition. The collected samples were sorted, sun-dried, quartered, and reduced to 1mm particles for proximate analysis. The results of MSW characterization revealed that non-organic combustible materials accounted for a higher percentage during the dry season (62.7%) compared to the rainy season (53.1%). Conversely, organic matter constituted a higher proportion during the rainy season (36.7%) compared to the dry season (30.4%). The moisture content ranged from 4 to 11%, volatile matter content varied between 60% and 66%, and fixed carbon content ranged from 19 to 31%. The energy content of MSW during the dry season was measured at 20.67 MJ/kg, while in the rainy season, it yielded 14.99 MJ/kg. These findings indicate that due to the substantial energy content and waste generation rates, waste-to-energy (WtE) technologies can be effectively applied to manage MSW in Yogyakarta, simultaneously reducing waste volumes and recovering energy.

A mini-review for identifying future directions in modelling heating values for sustainable waste management.

Global estimations suggest energy content within municipal solid waste (MSW) is underutilized, compromising efforts to reduce fossil CO2 emissions and missing the opportunities for pursuing circular economy in energy consumption. The energy content of the MSW, represented by heating values (HVs), is a major determinant for the suitability of incinerating the waste for energy and managing waste flows. Literature reveals limitations in traditional statistical HV modelling approaches, which assume a linear and additive relationship between physiochemical properties of MSW samples and their HVs, as well as overlook the impact of non-combustible substances in MSW mixtures on energy harvest. Artificial intelligence (AI)-based models show promise but pose challenges in interpretation based on established combustion theories. From the variable selection perspectives, using MSW physical composition categories as explanatory variables neglects intra-category variations in energy contents while applying environmental or socio-economic factors emerges to address waste composition changes as society develops. The article contributes by showing to professionals and modellers that leveraging AI technology and incorporating societal and environmental factors are meaningful directions for advancing HV prediction in waste management. These approaches promise more precise evaluations of incinerating waste for energy and enhancing sustainable waste management practices.

Experimental Study on the Temperature-Dependent Static, Dynamic, and Post-Dynamic Mechanical Characteristics of Municipal Solid Waste.

Municipal solid waste (MSW) has huge potential to be recycled as construction material, which would have significant benefits for environmental conservation. However, the cornerstone of this undertaking is a solid comprehension of the mechanical response of MSW in real-world engineering locations, taking into account the effects of stress levels and temperature. In this paper, well-mixed MSW samples were sieved and crushed to produce standardized specimens in cylindrical molds. A series of static, dynamic, and post-cyclic shear tests were conducted on the MSW at temperatures ranging from 5 °C to 80 °C with normal stresses of 50 kPa, 100 kPa, and 150 kPa. The experimental findings demonstrate that the static, dynamic, and post-cyclic mechanical response of MSW presents temperature range-dependency; temperature variation between 5 °C and 20 °C affects MSW's mechanical reaction more than variation in temperature between 40 °C and 80 °C under various stress settings; at 5 °C~80 °C, the static peak shear strength of MSW is the highest, being followed by the post-cyclic peak shear strength, while the dynamic peak shear strength is the lowest; the sensitivity of the dynamic shear strength of MSW to temperature variation is the largest, being followed by the post-cyclic peak shear strength, and the static peak shear strength is the lowest.

Disinfection efficacy of slightly acidic electrolyzed water on microorganisms: Application in contaminated waste sorting rooms across varied scenarios

Various pathogenic microorganisms present in municipal solid waste (MSW) can pose significant hazards to both the environment and public health. Spraying Slightly Acidic Electrolyzed Water (SAEW) is an effective method for decontaminating microorganisms in the air and on surfaces in the waste sorting rooms. SAEW treatment, with an effective chlorine concentration (ECC) of 28.4–44.5 mg/L and a pH range of 5.0–6.5, was conducted in the waste sorting rooms of the old, high-rise, and villa residential communities in Shanghai, China. The efficacy of SAEW treatment was assessed by examining the microbial population in the air, on waste containers, on sanitation workers' hands, and the microbial community structure of MSW samples. SAEW treatment resulted in the total bacterial reduction ranging from 0.07 to 1.70 log10 colony-forming units (CFU)/cm2 on waste containers, with corresponding reduction efficiencies between 15.7% and 98.0%. Additionally, the positive rates of coliforms were decreased by 18.7%–95.2%. Furthermore, the application of SAEW demonstrated a significant impact on reducing airborne bacterial and fungal levels. SAEW was proven effective on object surfaces, in the air and on human skin, achieving disinfection efficiencies ranging from 22.7% to 54.3% on sanitation workers’ hands. And the most significant inhibition of microbial growth was observed in the waste sorting room of the villa residential community. The microbial diversity and structure of MSW samples exhibited noticeable differences before and after the SAEW application. These findings suggest that SAEW holds significant potential as an ideal, environmentally friendly broad-spectrum disinfectant for preventing and controlling microbial contamination in the waste sorting rooms.

Estimation of calorific value using an artificial neural network based on stochastic ultimate analysis

The main aim of the present study was to estimate the calorific value (CV) by considering the uncertainty in municipal solid waste (MSW) generation using a cohesive Artificial Neural Network (ANN) technique. The parameters from ultimate analysis are taken as input data and CV as output data for 300 samples and seasonal variation is considered for predicting CV. Monte Carlo Simulation Technique is applied to deal with the uncertainty in MSW characteristics and the Simultaneous Backward Reduction (SBR) approach is used to tackle scenarios into a manageable number. Various ANN models were built based on the seasonal variation for three cities: ANNMS, ANNMW, ANNUS, ANNUW, ANNBS and ANNBW. The results depicted that network ANNMS for the architecture (9-21-1) has a minimum MAPE value of 1.22% with an estimation accuracy of 94.61%. The network ANNUS has a minimum MAPE of 1.62% has an estimation accuracy of 93.2% for the architecture (9-23-1). The network ANNBW Baddi City has a minimum MAPE is 2.23% for the network (9-21-1) with an estimation accuracy of 91.77% respectively. The developed ANNs model in the present study is beneficial to estimate the CV of MSW samples using elemental composition considering the uncertainty in the data, leading to more accuracy in the prediction models. It helps to minimize experimental costs and gives a theoretical background for modeling MSW's energy potential based on Waste to Energy (WTE) technologies.

Source analysis of chlorine in municipal solid waste under waste classification: a case study of Hangzhou, China.

Inorganic chlorine is susceptible to water and soil salinization due to its non-degradability and high mobility. To clarify the environmental risks associated with the active inorganic chlorine in municipal solid waste (MSW), the specific characteristics and contributions of inorganic chlorine in different MSW categories were investigated in this study. MSW samples were collected from eight representative waste classification residential areas in Hangzhou, China. It was found that the inorganic chlorine content in different MSW categories varied significantly (0-113 mg/g). Perishable waste, paper, and plastic were found to be the main sources of inorganic chlorine in MSW. A four-category classification system was used to quantify the contribution of inorganic chlorine from each waste category. It was found that the misclassification of inorganic chlorine contributions from perishable waste and other waste accounted for 51.96% and 48.04%, respectively. However, when correctly classified into the four-category system, their contributions were reduced to 67.14% and 30.65%, respectively. Therefore, MSW classification showed a significant reduction in the overall contribution of inorganic chlorine. The misclassification reduces the contribution of inorganic chlorine to 48.04%, while correct classification increases the reduction to 69.35%.

Harnessing Abuja's Municipal Solid Waste as a Renewable Energy Source: Scanning Electron Microscopy Analysis

A study of Abuja’s municipal solid waste (MSW) samples using the scanning electron microscopy analysis was undertaken in this work. In the face of the severe energy poverty being experienced in Nigeria which largely depends on diminishing fossil fuel resources coupled with the associated problem of greenhouse gas emission, the energy potential available in municipal solid wastes needs to be investigated. Using MSW as a fuel source for electric energy production will also positively impact on Abuja’s waste management. This present study requires the analysis of the MSW with aim of confirming that products of its incineration will not be hazardous to the environment. ASTM E 1508 procedures for utilizing the scanning electron microscope (SEM) were followed to identify elements that would be contained in the bottom ash of the incineration process of samples of Abuja’s municipal solid wastes obtained from selected districts of the city. Elemental composition of the bottom ash that will be formed from incineration of Abuja’s MSW was obtained by the use of energy dispersive x-ray analysis. The micrographs plotted indicate that silicon and iron are the principal elements present in the samples with values for silicon and iron being highest at 49.5 and 19.55%, respectively, for the sample from Dutse-Alhaji. The tests also show the presence of silver in the organic wastes generated in Abuja, while presence of sulphur is very minimal. The silicon levels present in Abuja’s municipal solid waste compare well with values for Nigerian coals which have percent silicon contents ranging from 39.0 – 49.4% (Enugu coal – 39.0%; Okaba – 44.8%; Maiganga – 49.4%). The test results also show that Abuja’s MSW samples had grain sizes ranging from 3.5 mm 16 mm. The results indicate Abuja’s MSW combustion rate will be lower than for pulverised coal which is known to have much lower grain size in the range of 75 μm to 106 μm and will need shredding before firing since grain size is a very critical determinant factor in solid fuel combustion rate and burn-out time. The tests conclusively show that Abuja’s MSW will be a more environmentally friendly fuel than coal because of its lower sulphur content.

Effect of geomembrane liner on landfill stability under long-term loading: interfacial shear test and numerical simulation.

Clay liners have been widely used in landfill engineering. However, large-scale clay excavation causes secondary environmental damage. This study investigates the feasibility of replacing clay liners with high-density polyethylene (HDPE) geomembranes with different specifications and parameters. Laboratory interface shear tests between municipal solid waste (MSW) samples of different ages and geomembranes were conducted to study the influence of landfill age on interface shear strength. Finite element method was adopted to compare the long-term stability of landfills with HDPE geomembrane versus clay as intermediate liner. The interfacial shear test results show that the cohesion of MSW increases in a short term and then decreases with landfill age. The internal friction angle exhibits an increasing trend with advancing age, however, the rate of its increment declines withage.The rough accuracy of the film surface can increase the interfacial shear strength between MSW. The simulation results show that, unlike clay-lined landfills, the sliding surface of geomembrane-lined landfills is discontinuous at the lining interface, which can delay the penetration of slip surfaces and block the formation of slip zone in the landfill. In addition, the maximum displacement of landfills with geomembrane is 10% lower than that with clay, and the absolute displacement of slope toe decreases with the increase of roughness at the interface of geomembrane. Compared with clay-lined landfills, the overall stability safety factor increased by 18.5-30%. This study provides references for landfill design and on-site stability evaluation, contributing to enhanced long-term stability.

A method for determining the recycling value of unprocessed municipal solid waste in one cubic meter waste composition analysis technique

The transition from conventional landfill-centric waste management to resource-centric methodologies necessitates an enhanced comprehension of municipal solid waste (MSW) composition and its inherent value. Existing methodologies documented in the literature exhibit a lack of standardization, impending the formulation of a systematic engineering approach for MSW characterization and valuation. This study introduces a methodology specifically tailored to discern the composition of waste origination from urban households and evaluate its recyclability within the confines of a circular economy framework, Employing a volume-based measurement approach, aims to estimate the recycling value of waste materials. The study's outcomes contribute significantly to quantifying the potential recycling value that accrues to society. Furthermore, the validation of the proposed protocol elucidates the dynamic nature of recyclable value as it traverses the intricate pathways of the waste supply chain. This insight facilitates the formulation of commercial models grounded in circular economy principles for the effective management of household solid waste. Empirical findings reveal that the total recycling value fluctuates within the range of USD 3.39 and USD 5.76 per cubic meter of waste volume, contingent upon the specific waste composition at the experiment site. Additionally, the proposed methodology uncovers the nuanced variability in MSW composition and recycling value across diverse household collection patterns, identifying mixed plastic, paper, cardboard, mixed MSW, and clothing as primary constituents. The application of this methodology extends beyond mere quantification, providing a foundational framework for simulating the latent recycling value embedded within MSW samples. This, in turn, offers invaluable support to strategy developers, policymakers, and entrepreneurial ventures engaged in the sustainable management of household solid waste. In essence, this study establishes the groundwork for a comprehensive understanding of MSW composition and its recyclability, facilitating informed decision-making in the pursuit of a circular economy.•Novel methodology based on one cubic meter (1m3) composition analysis of Municipal Solid Waste (MSW).•A new method to evaluate the recycling value of Municipal Solid Waste.•A basis for business model development for the waste-to-resource conversion model.

Biodrying of municipal solid waste-correlations between moisture content, organic content, and end of the biodrying process time.

Biodrying refers to the decomposition of organic municipal solid waste (MSW) under aerobic conditions. This process usually lasts 14days and requires large amounts of air to be injected into the waste matrix. The efficiency of the biodrying process depends on several geotechnical parameters, including initial moisture content, initial organic content, bulk density, dry density, solid particle density, and porosity. To examine the potential influence of these parameters on the biodrying process, we analyzed 13 biodried MSW samples. The results revealed a strong positive linear relationship between the initial moisture content and the mass loss percentage. In the first three days of the biodrying process, the waste mass rapidly decreased; afterwards, the daily mass loss occurred at a less rapid, more constant rate. The established average mass removal ratio between the volatile solids and water was 1:6.38 with a standard deviation of 1.06. Dry and solid particle densities were preserved in all 13 experiments; thus, the corresponding void ratio remained unchanged. This finding suggests that the settlement and degradation of MSW that occur during the biodrying process did not significantly influence the airflow rate.

Characteristics of Municipal Solid Waste in Some Urban Agglomeration in the Past Five Years

The treatment and disposal of municipal solid waste has increasingly become a common concern around the world, and the characteristics of municipal solid waste(MSW) are an important basis for the selection of terminal treatment methods. In this study, more than 400 MSW samples from over 30 cities across China were collected, and the basic physical and chemical properties, such as the physical composition, pollutant content, and calorific value, were analyzed. Shenzhen was taken as an example to analyze the influence of time and waste sorting measures on the physical and chemical characteristics of MSW. The correlation model between MSW composition and calorific value was established using partial least squares(PLS) regression, and the model was verified. The results showed that with per capita GDP increasing by 10,000 yuan, per capita MSW production and the low calorific value of MSW increased by 0.1 kg·(person·d)-1 and 373.8 kJ·kg-1, respectively. However, when per capita GDP was less than 60,000 yuan, the correlation between per capita GDP and per capita MSW production was relatively poor. Kitchen waste was still the most abundant component of MSW, and the content of most samples was between 40% and 60%. The combustible content of rubber/plastic and paper was relatively high, between 20%-30% and 10%-20%, respectively. The inorganic content did not usually exceed 5%, and the moisture content of the MSW was between 50% and 60%. After the implementation of waste classification in 2019, the content of kitchen waste in MSW had been significantly reduced, the content of rubber/plastic had increased, and other components had not changed much. Additionally, the calorific value of waste had been improved to a certain extent. The pollution element contents in MSW, S Cl, and N were all below 1%, and the average value was:N>Cl>S. The contents of Hg, As, Cr, Cd, and Pb in MSW samples did not change significantly with the composition and sampling time, and the content of Pb and Cr in MSW was affected by the environmental background value. The model analysis revealed that rubber/plastics and moisture content were the main variables that affected the calorific value of MSW. The deviation between the measured value and the predicted value was less than 20% for 85.96% of the samples. The model established in this study can meet the needs of the prediction of the calorific value of MSW.

Characterisation of Waste and Assessment of Surface Methane Emissions by Static Chamber Technique at a Major Dumping Site in Central India

Given the vast amount and higher organic content of waste generated by developing nations such as India, as well as the challenges related to waste management and global warming, controlling methane emissions from such municipal solid waste (MSW) dumpsites becomes a major concern. As a result, studying the characteristics of solid waste dumped and the subsequent emissions of methane (CH4) from a site lacking proper disposal and gas emission management facilities, as is common in developing countries, becomes more important for suggesting appropriate corrective measures. In this study, MSW samples were collected from the Bhandewadi dumping site, a prominent site in Nagpur city and subjected to proximate, ultimate, and biochemical analysis. The results showed that the waste had high moisture content due to the tropical climate of the region which, together with the greater carbon content and organic matter (OM), may be responsible for increased overall greenhouse gas emissions. Biochemical study, on the other hand, revealed lower lignin content when compared with cellulose and hemicellulose, which are key contributors to CH4 emissions. The actual on site measurements using static chamber technique at fresh dumping sites showed that the methane (CH4) flux was between 1 and 14.3 mg m-2 sec-2 and 0.9 to 7.11 g m-3 day-2 at old dumping areas. The study contributes to a better understanding of the amount and unpredictability of methane produced by solid waste in an unmanaged dumping site.

Evaluation of the Methane (CH4) Generation Rate Constant (k Value) of Municipal Solid Waste (MSW) in Mogadishu City, Somalia

Landfills are the third largest source of the greenhouse gas methane, contributing to 25% of global warming. Therefore, the characterization of national municipal solid waste (MSW) and estimation of methane generation rate are very important for the solid waste management (SWM) toward sustainable development goal no. 13, climate action. This study presents (a) an assessment of daily MSW generation, (b) the characterization of MSW, and (c) an evaluation of the methane generation rate constant (k value) in Mogadishu, Somalia. The MSW samples were collected from three (3) sampling zones (Zones 1, 2, and 3; 204 households) and weighted (kg). Next, the waste generation per person per day was estimated. The MSW characterization includes sorting (based on plastic/polythene, food wastes, wood, metals, yard waste, paper/cardboard, textile, glass/ceramic and miscellaneous components, %), the determination of bulk density (kg/L), and measuring moisture content (%). The k values were evaluated from the percentages of different components in MSW based on first-order decay models. Mogadishu city generated 1671.03 kg MSW per week (maximum on Friday: 348.72 kg, and minimum on Monday: 152.04 kg). The total mean MSW generation rate observed in this study was 0.2 kg/person/day. The solid waste generation found was in the decreasing order of food waste > plastic/polythene > yard waste > miscellaneous > papers/carboard > wood > glass/ceramic > textiles > metals by weight. The average bulk density was found to be 0.269 kg/L. The average moisture content was ranged from 61.6 to 73%. The total k values were categorized as fast (Zone 1: 0.216053 yr−1, Zone 2: 0.228739 yr−1, and Zone 3: 0.244595 yr−1) and moderate (Zone 3: 0.244595 yr−1) degradation. This research serves as Somalian MSW baseline data and projected the methane generation rate from the MSW production in the country. The MSW sorting may reduce the impact of global warming and is highly recommended for better SWM in the future.

Roles of ageing on the physical, chemical and mechanical parameters of a prototype municipal solid waste

ABSTRACT This study is mainly aimed at exploring effects of the aging-induced chemical decomposition of Municipal Solid Waste (MSW) on the shear response and physical properties of locally available MSW of Fars province, Iran, at its in-situ condition. To this end, a large direct shear device (1×1×1.1 m3) is designed, fabricated and employed to evaluate the parameters of the failure envelop at plane strain condition representing slopes of engineered landfills. Bulk disturbed samples of fresh MSW are exhumed from an operational disposal site to be implemented into the study and subsequently remolded in the large-scale shear box. Four drained shear tests are performed under a variety of vertical stresses. Next, intact components of MSW are landfilled over a period of 3, 6, and 9 months. Similar shear experiments are conducted at the end of each mentioned time interval. Mechanical behavior of MSW is completely frictional and internal friction angle of the studied MSW non-linearly increases with time from 44.2º to 55.7º. The stress-strain response is almost bilinear over a wide range of displacement. The decomposition process is further clarified in light of results of pH tests conducted on the leachate of the MSW at the end of various landfilling time intervals.

Characterization of landfills solid waste in Muscat and estimation of their energy recovery.

The only way to dispose of municipal solid waste (MSW) in Oman is in engineered landfills without pre-treatment. An effective waste management system requires a reliable database of solid waste composition, properties, and energy content. Although investigating waste in landfills in Muscat Governorate is challenging and complex, it is essential. In this study, MSW from Muscat Governorate landfills is examined. The MSW samples were collected et al. Amerat and Barka landfills in 2020 in order to determine some of the importance of their physiochemical properties and the ratio of materials (food, plastic, and paper). It was found that approximately 50% of the weight of the disposed waste was recyclable. There were high levels of biodegradable organic material in MSW. In terms of moisture content, MSW ranged from 21.5 to 43.3%. Both the volatility and loss of ignition of MSW were high. It was found that the total oxide ratios ranged from 12.4 to 44.06%. The elemental analysis of Muscat MSW resulted in six chemical formulas for MSW with and without sulfur. Silica is the most influential oxide, followed by calcium oxide. The findings of this study indicate that almost half of Muscat's municipal solid waste can be recycled. Solid waste can be recycled to create renewable materials that can replace oil as a by-product of the recycling industry. Additionally, Muscat MSW has a high moisture content, which enables it to be composted and biodegraded. Moreover, waste-to-energy technologies are feasible due to their high-energy content.

The Thermochemical Conversion of Municipal Solid Waste by Torrefaction Process

In this work, the thermochemical properties of municipal solid waste (MSW) are studied using the torrefaction process as the main method for investigation. Torrefaction experiments were carried out using an electric laboratory furnace, at temperatures of 200, 250, and 300 °C. The residence time was set to 90 min. Proximate and ultimate analysis were performed on the torrefied MSW samples and compared with the properties of the raw MSW samples. In addition, the thermal properties of the obtained torrefied MSW samples were evaluated by thermogravimetric analysis (TGA) and derivative thermogravimetric analysis (DTG). The following could be stated: the obtained results showed that mass and energy yields (MY and EY, respectively) decrease with increasing when torrefaction temperature, while the heating values (HHV) increased under the same conditions (from 24.3 to 25.1 MJ/kg). Elemental analysis showed an increase in carbon content (C), from 45.7 ± 0.9 to 52.8 ± 1.05 wt.%, and decrease in oxygen content (O), from 45.6 ± 0.9 to 39.5 ± 0.8 wt.%, when torrefaction temperature is increased, which is consistent with the general definition of the torrefaction process. In addition, enhancement factors (EFs) and fuel ratios (FRs) were calculated, which ranged from 1.00 to 1.02 and 0.16 to 0.23, respectively. Some anomalies were observed during the thermal analysis, which are assumed to be related to the composition of the selected MSW. This study therefore shows that torrefaction pretreatment can improve the physicochemical properties of raw MSW to a level comparable to coal, and could contribute to a better understanding of the conversion of MSW into a valuable, solid biofuel.

Physicochemical Characterisation of Abuja’s Municipal Solid Wastes as a Renewable Energy Resource

Physical and chemical composition analyses of Abuja’s municipal solid waste samples have been carried out in this study. Laboratory procedures were employed to determine the higher calorific value, the proximate analysis and ultimate analysis of MSW samples from selected districts of Abuja metropolis. An analytical methodology was therefore employed to determine whether the city’s MSW will be good resource for energy generation as a strategy for effective waste management. Abuja’s MSW has an aggregate higher heating value of 38.13MJ/kg. Moisture content of less than 8% obtained for all the samples compares very well with values for Nigerian coals. Volatile matter was found to be above than 60% for each samples tested while fixed carbon was determined to be less than 26% for each sample. The MSW samples gave excellent results for ash content of less than 4% when compared to most Nigerian coals with minimum ash content of 10.72%. The ultimate analysis shows the MSW samples compares fairly well with Nigerian coal samples in terms of elemental carbon, the least value being 41.80%. The least value for elemental carbon in most coal samples is 53.27%. Also, the sulphur content of the MSW samples is much less (not higher than 0.15%), compared with the least value of 0.58% for the coal samples. All the factors considered above indicate that the Abuja’s MSW will perform very well as a primary solid fuel when incinerated for energy recovery. The economic significance of this study lies in the confirmation that Abuja’s MSW is a good and cheap source of energy for electric power generation, replacing the expensive fossil fuel sources with their attendant hazardous emission to the environment. This will make the study area to be a cleaner and healthier environment.

Occurrence and ecological risks of microplastics and phthalate esters in organic solid wastes: In a landfill located nearby the Persian Gulf

Landfill sites are the main source of plastic waste. Thus, municipal solid waste (MSW) in landfills may act as a reservior of microplastics (MPs) and related pollutants such as phthalate esters (PAEs) into surrounding environment. However, there is limited information on MPs and PAEs in landfill sites. Levels of MPs and PAEs in organic solid waste disposed in a landfill of Bushehr port were investigated for the first time in this study. The mean MPs and PAEs levels in organic MSW samples were 12.3 items/g and 7.99 μg/g, respectively, and the mean PAEs concentration in MPs was 87.5 μg/g. The highest number of MPs was related to the size classes of >1000 μm and <25 μm. The highest dominant type, color, and shape of MPs in organic MSW were nylon, white/transparent, and fragments, respectively. Di (2-ethylhexyl) phthalate (DEHP) and diisobutyl phthalate (DiBP) were the dominant compounds of PAEs in organic MSW. Based on the finding of present study, MPs showed a high hazard index (HI). DEHP, dioctyl phthalate (DOP), and DiBP demonstrated high-level hazards for sensitive organisms in water. This work illustrated considerable MPs and PAEs levels from an uncontrolled landfill without adequate protection, possibly contributing to their release into the environment. The sites of landfill located near marine environments, such as Bushehr port landfill adjacent to the Persian Gulf, may indicate critical threats to marine organisms and the food chain. Continuous landfills control and monitoring, especially the ones near the coastal area, is highly recommended to prevent further environmental pollution.

Methane Emission and Carbon Sequestration Potential from Municipal Solid Waste Landfill, India

Quantities of waste generation are drastically increasing every day, and most of the waste is disposed of through open dumps and landfilling. Methane, carbon dioxide, and nitrous oxide are major greenhouse gases (GHGs) produced from landfill sites. However, the global-warming potential of methane is 21 times higher than that of carbon dioxide. Hence, there is immense concern for its utilization from landfill sites. In developing countries, the composition of municipal solid waste (MSW) has high amounts of biodegradable waste (50–60%). This leads to higher emissions of GHGs a per ton of MSW compared to the developed world. In this study, the attempt will be made to estimate the amount of carbon stored in MSW burial in landfills. Tests were conducted in two different locations at the Mavallipura landfill. MSW samples were collected for every meter interval (1–2 m, 2–3 m and so on) up to 6 m. The result shows that carbon stored in organic matter increases with depth from approximately 2.2% at 1.0 m depth to 4.8% at 6 m depth. Based on MSW’s carbon storage factor and data on MSW generation, global carbon sequestration from MSW burial in the Mavallipura landfill is estimated to be at least 10 million metric tons per year. In additional, the study aims to quantify methane-gas production from the ward levels and the Mavallipura landfill site in India.

Effects of moisture content and landfill age on the shear strength properties of municipal solid waste in Xi'an, China.

With the continued expansion of waste landfills, accidents may occur if the landfills are not properly stabilized. In this study, samples of municipal solid waste (MSW) from a waste landfill in Xi'an, China were collected through on-site drilling. Considering the effects of nine landfill ages (1, 2, 3, 11, 12, 13, 21, 22, and 23 y) and six moisture contents (natural, 20, 40, 60, 80, and 100%), 324 groups of MSW were tested in the laboratory using a direct shear test apparatus. The results indicate the following: (1) with an increase in horizontal shear displacement, the shear stress of MSW gradually increases without a peak stress phenomenon, which is a displacement hardening curve; (2) with an increase in landfill age, the shear strength of MSW increases; (3) with an increase in moisture content, the shear strength of MSW increases; (4) with an increase in landfill age, the cohesion (c) decreases and the internal friction angle (φ) increases; and (5) with an increase in moisture content, the c and φ of MSW increases. The c range found in this study was 6.04-18.69kPa, while the φ was 10.78-18.26°. The results of this study can provide a reference for stability calculations for MSW landfills.