Landfill Research Articles

Semi-Aerobic Landfill System as Alternative Solution for Indonesian Landfill

Indonesia has been encountering pressing problems in managing municipal solid waste (MSW). According to data from the Ministry of Environment and Forestry (KLHK), up to 35.46% of landfills were run as open-dumping landfills until May 2022 because proper sanitary landfill concepts were not fully implemented and the condition of landfills in Indonesia is on the point of being overcapacity. With the development of landfill technology, the Ministry of Public Works is currently starting to develop other alternative landfill systems. From the general findings of this study, it can be concluded that the semi-aerobic landfill system is an available method to be used as an alternative solution for Indonesian landfills. This is based on the results of the SWOT matrix, which shows strategic factors derived from internal and external factors originating from previous studies and issues regarding landfills in Indonesia. The analysis of these factors shows that the semi-aerobic landfill system produces better performance by reducing the potential for environmental pollution of water and air and greenhouse gas emissions. The implementation of a semi-aerobic landfill system is a viable method to be used in developing countries.

Experimental and molecular dynamic simulation studies of landfill contaminated groundwater remediation by graphene oxide coated zeolite

ABSTRACT Graphene oxide (GO) has proven effective in wastewater treatment due to its capability to adsorb heavy metals and organic contaminants. Zeolite is also widely used in contaminant remediation as a reactive material in permeable reactive barrier (PRB). Experimental column flow-through tests were applied in this study to investigate the remediation ability of composite granule-graphene oxide coated zeolite (GOZ) on FA, Pb2+ and NH4 +, from municipal landfill contaminated groundwater. Microscopic characterization and molecular dynamic simulation were carried out in sequence to understand the adsorption process. The results demonstrated that GO significantly enhanced zeolite’s adsorption capacity for Pb2+ and FA by 147.5% and 164.8%, respectively, though NH4 + removal experienced a slight decrease of 25% after GO coating. The ion exchange of Pb2+ resulted in more significant partial collapse compared to NH4 + due to different effective diameter comparing with the channel size of zeolite. However, GO coating relieved the framework deformation by engaging in functional group reactions during Pb2+ adsorption. A recommended surface area coating ratio between 47.0% and 78.4% was identified, as values outside this range may lead to significant GO deformation or inefficient FA adsorption. The GO-zeolite granules displayed significant potential in remediating various contaminants while effectively preventing GO aggregation and zeolite collapse. As technological advancements reduce GO production costs, the economic feasibility of using GOZ in groundwater remediation is increasingly promising.

Characteristics and pollution indices of leachates from municipal solid waste landfills in Iranian metropolises and their implications for MSW management

Leachate from municipal solid waste landfills poses a significant threat to aquatic ecosystems due to poor management practices. This study evaluated thirty leachate samples from Iranian metropolises using the Leachate Pollution Index (LPI). Various parameters, including BOD₅, COD, TDS, pH, EC, heavy metals, turbidity, PAHs, phthalates, and humic acid, were analysed. The BOD₅ levels ranged from 350 to 20,000 mg/L, and the COD levels ranged from 2,000 to 90,000 mg/L. The TDS content varied between 14.7 and 67 g/L, while the turbidity ranged from 15 to 186 NTU. Heavy metals were present but within standard limits. The phthalate concentrations ranged from 6 to 150.8 mg/L, and the humic acid concentrations ranged from 135 to 2,200 mg/L. Naphthalene was the most frequent hydrocarbon detected. The LPIs were less than 30 for all the samples, with the highest in Ahvaz and the lowest in the treated samples from Tehran. This study highlights the presence of persistent organic and hazardous contaminants in Iran’s municipal landfills, emphasizing the need for effective leachate treatment and improved waste management practices. Enhanced final disposal methods, increased waste recovery, and improved solid residue separation are crucial for preventing further leachate production and environmental contamination.

Methane Generation Potential of the Easily Degradable Group of Landfilled Municipal Solid Waste

Municipal solid waste (MSW) remains in sanitary landfills for many years. To maintain a circular economy, assessing the feasibility of reinserting MSW excavated from sanitary landfills into the production chain is important. This reduces environmental impacts, helping to minimize soil, water, and air pollution resulting from the decomposition of waste in landfills. In addition, it promotes economic benefits from the energy recovery of waste, such as biomass, which can generate electricity and heat, contributing to a sustainable energy matrix. The present study aimed to evaluate the easily degradable MSW group with 24 years of landfilling (ED-24) regarding its potential for methane generation. The ED group consisted of putrescible organic matter, wood, paper, cardboard, and pruning landfilled at a sanitary landfill in Southeastern Brazil. The feasibility of valuing ED-24 as a substrate for anaerobic digestion was assessed by analyzing its physical, chemical, and biochemical characterization and calculating its theoretical methane yield (TMY). The total volatile solids (TVS) and holo-cellulose contents of ED-24 were 73.45% and 61.39%, respectively, on a dry-weight basis. These values were in the range of those determined for non-landfilled lignocellulosic materials. Thus, 24 years of landfilling partially degraded the anaerobically lignocellulosic materials. The TMY of ED-24 was 233.41 mL CH4/g TVS, indicating a potential to generate methane. Despite the high lignin value, ED-24 can be valued as a substrate for anaerobic digestion.

Physico-chemical and biological characterization of urban municipal landfill leachate and treatment by ozone process

Thewaste production nationwide is increasing every year, on account of therapid urbanization and growing populations, also consumption modes. Algerian political authorities have chosen Technical Landfill Centres (TLC) as a competitive and safe technique of waste management.However, storing these wastes in a bad way poses several environmental challenges, especially in the Department of Saïda, the latter have significant groundwaters. The major problem registered on this Landfill is the leachate resulting from the degradation of buried wastes which were disposed off the outside of the leachate basinand present a source of pollution for the local groundwaters by heavy metals and pathogenic germs.The present paper investigates the leachate treatment ozone process produced by Dielectric Barrier Discharge (DBD) under high potential.The experimental resultsobtained allowed us to show the efficiency of the treatment process by ozone based on the micro pollutant analysis (COD, BOD5 , TOC, heavy metals) and microbial analysis, after ozonation treatment.The results show that 80% of micro pollutants are eliminated and 100% destruction of all bacteria which reveals the high efficiency of the process.

Features of Landfill Reclamation in the North-Western Region of Russia

Ecological and climatic features of solid municipal waste landfills in the north-western region of the Russian Federation are considered. It was noted that it is impossible to use the land for the intended purpose, stipulated by regulatory documents, immediately after completion of waste disposal. The incorrectness of the current regulatory documents in relation to the north-western region of Russia is emphasized. The expediency of reclamation in two stages is substantiated: at the first stage, the sanitary-hygienic direction is carried out – the creation of phytocenoses of anti-erosion and aesthetic purpose, at the second stage (after 2–3 decades and more) after assessment of the ecological situation in the landfill area the direction of reclamation is chosen and the target (economic) land use is established.

Mathematical Modeling of Biogas Production in Sanitary Landfills

Objective: The objective of this study is to evaluate the biogas production potential in sanitary landfills using the Verhulst mathematical model, which is employed to represent natural phenomena constrained by a saturation point. Theoretical Framework: It was based on references on energy use from waste, possible conversion routes, in addition to mathematical models that estimate the energy potential for biogas generation. Method: The methodology adopted for this research involves the use of data collected in an experimental cell, subsequently applying the De Verhulst model through a regression with minimization of errors using the Least Squares Method (LSM). Results and Discussion: The results indicated that the developed model correlates well with the observed data, demonstrating its suitability as a predictive model for biogas production. Research Implications: The research contributes to the construction of a theoretical framework for the adaptation, elaboration and use of mathematical models to predict the energy potential in the generation of biogas in landfills. Originality/Value: This study contributes to the literature by using a population growth model (Verhulst) to predict landfill biogas production.

Characterization of microplastics in soil, leachate and groundwater at a municipal landfill in Rayong Province, Thailand

Recent years have witnessed a dramatic increase in global plastic production, leading to heightened concerns over microplastics (MPs) contamination as a significant environmental challenge. MP particles are ubiquitously distributed across both continental and marine ecosystems. Given the paucity of research on MPs in Thailand, particularly regarding MPs contamination in terrestrial environments, this study focused on investigating the distribution and characteristics of MPs in a landfill area. We collected 15 soil samples, 2 leachate samples, and 5 groundwater samples from both inside and outside a municipal landfill situated in the urbanized coastal region of Rayong Province. Our findings revealed variability in MPs concentration across different sample types. In soil, the MP count ranged from 240 to 26,100 pieces per kg of dry soil, 58.71 % of all sample sizes are lower than 0.5 mm. Similarly, the size found in the leachate sample, and the average MP in the leachate samples was 139 pieces per liter of MPs. The groundwater samples showed a fluctuation in MPs count from 26 to 94 pieces per liter, and the size of MPs ranged mostly from 0.5 to 1 mm. The predominant forms of MPs identified were sheets, followed by fragments, fibers, and granules. According to μ-FTIR analysis, the majority of the MPs were composed of polyethylene and polypropylene, commonly used in plastic packaging and ropes. The observed high concentrations and extensive distribution of MP contamination underscore the urgency for further studies and effective management strategies to mitigate the adverse impacts of this pollution on various organisms and ecosystems.

Heat mitigation in basal compacted clay liners in municipal solid waste landfills.

In municipal solid waste (MSW) landfills, biodegradation of the organic MSW fraction results in elevated waste and basal liner temperatures which have the potential to cause the clay component of the basal liner to experience severe moisture loss over time and eventually undergo desiccation cracking. Cracking of the basal liner's clay component would result in an uncontrolled release of contaminants into the surrounding environment and ultimately give rise to a variety of major environmental concerns. Accordingly, this study examined the variation of temperature-moisture profiles along the depth of a compacted clay liner (CCL) exposed to different constant elevated waste temperatures (CETs) in the absence and presence of two heat reduction techniques, respectively. Rockwool insulation layers with varying thicknesses and galvanized steel cooling pipes with varying flowrates were introduced separately as the two heat reduction techniques. Introduction of both techniques led to a significant attenuation of the temperature rise and desiccation experienced by the CCL in the face of different CETs. An increase in rockwool thickness increments led to a progressive reduction of CCL temperature, while an increase in flow rate under turbulent condition did not have a significant influence on the temperature and desiccation reduction of the CCL. Nevertheless, the present study certainly highlights the potential of the two proposed heat reduction techniques to minimize desiccation and consequently increase the service life of CCLs exposed to different elevated temperatures in MSW landfills.

Preparation of A Map of Potential Areas For the Installation of A Sanitary Landfill in The Porto Murtinho/MS Region

Objective: The main objective is to prepare a map to identify areas with potential for the installation of a landfill in the region of Porto Murtinho/MS. Theoretical Framework: This study addresses the relevance of the careful selection of locations for the implementation of Sanitary Landfills, with an emphasis on environmental and social aspects, using geotechnologies as fundamental tools for a comprehensive and effective analysis. Method: The mapping was based on the acquisition and processing of geospatial and environmental data. The factors were classified as limiting or not, considering watercourses, areas subject to flooding, roads, land use and occupation, slope, soil and urban proximity. Data integration through map algebra was performed in QGIS software, and WRPLOT View was used for wind analysis. Results and Discussion: The results revealed that the majority of areas with high installation potential are located at a distance of 2 (two) to 5 (five) kilometers from the urban perimeter. The supplementary analysis of Rosa dos Ventos demonstrated that areas located to the east are more suitable for the implementation of sanitary landfills. Research Implications: The multifaceted approach, which includes environmental and operational aspects, makes it possible to identify areas suitable for the implementation of sanitary landfills. Originality/Value: This study demonstrates the relevance of geotechnologies in choosing locations for landfills, where limiting factors exclude unsuitable areas, and non-limiting factors classify the installation potential, being a methodology replicable in other locations for sustainable environmental management.

Effect of the spatial changes in engineering properties on municipal solid waste landfill slope stability

Effect of the spatial changes in engineering properties on municipal solid waste landfill slope stability

Quantification and characterization of municipal solid waste at aler dumpsite, Lira City, Uganda: Assessing pollution levels and health risks

Managing municipal solid waste (MSW) in urban areas of developing countries is a significant challenge due to rapid urbanization and inadequate infrastructure. This study aims to quantify the MSW at Aler dumpsite in Lira City, Uganda, and assess the associated environmental and health risks. Our findings revealed a daily dumping rate of 7.38 tons, predominantly organic waste. Leachate from the site exceeded WHO limits for nutrients and heavy metals, with exceptionally high amounts of cadmium (Cd) found in soil (4.8 mg/kg) and vegetables. The water quality in nearby streams was poor, rendering it unfit for consumption due to elevated ion and nutrient levels. Health risk assessments indicated significant non-carcinogenic risks from heavy metal ingestion, with a hazard index (HI) of 4.6 for adults and 9.6 for children. While dermal exposure risks were generally low, children were at risk from stream 1 (HQderm = 1.165). Vegetable analysis revealed levels of lead (Pb), cadmium (Cd), zinc (Zn), and nickel (Ni) above safe doses, posing significant non-carcinogenic risks. To address these issues, we recommend increasing public awareness to avoid consuming water and vegetables from areas around the dump site. Additionally, we suggest that the responsible authorities improve MSW management by constructing sanitary landfills to minimize water, soil, and plant pollution from landfill leachate.

Analysis of long-term MSW settlement based on field data measured at two closed landfills

Waste settlement characteristics vary depending on waste composition, physical properties, waste management operations, and time. In this study, the post-closure waste settlement behavior was analyzed using field data measured at two closed municipal solid waste landfills in Korea, for 23 and 5 years after landfill closure. The long-term waste settlement data was analyzed to derive a time-varying long-term compression ratio (CLT) that was consistent with modeled biodegradation processes. A statistical assessment of the field data was conducted to examine the relationship between CLT and several factors that may affect the observed settlements. The CLT of Landfill #1 and #2 was found to vary between the two landfills that had differences in the percentage of organic matter (B0), total unit weight (γwaste), and moisture content (w) due to changes in waste management policies.

Geoenvironmental Effects of the Hydric Relationship Between the Del Sauce Wetland and the Laguna Verde Detritic Coastal Aquifer, Central Chile

In the central region of Chile, the Mega-Drought together with the demographic increase near the coast threatens groundwater availability and the hydrogeological functioning of coastal wetlands. To understand the hydric relationship between an aquifer and a wetland in a semi-arid coastal region of Central Chile (Valparaíso, Chile), as well as its geoenvironmental effects, four data collection campaigns were conducted in the wetland–estuary hydric system and surroundings, between 2021 and 2022, including physical, hydrochemical, and isotopic analyses in groundwater (n = 16 sites) and surface water (n = 8 sites). The results generated a conceptual model that indicates a hydraulic connection between the wetland and the aquifer, where the water use in one affects the availability in the other. With an average precipitation of 400 mm per year, the main recharge for both systems is rainwater. Three specific sources of pollution were identified from anthropic discharges that affect the water quality of the wetland and the estuary (flow from sanitary landfill, agricultural and livestock industry, and septic tank discharges in populated areas), exacerbated by the infiltration of seawater laterally and superficially through sandy sediments and the estuary, increasing salinity and electrical conductivity in the coastal zone (i.e., 3694 µS/cm). The Del Sauce subbasin faces strong hydric stress triggered by the poor conservation state of the riparian–coastal wetland and groundwater in the same area. This study provides a detailed understanding of hydrological interactions and serves as a model for understanding the possible effects on similar ecosystems, highlighting the need for integrated and appropriate environmental management.

A Novel First-Order Kinetic Model for Simultaneous Anaerobic–Aerobic Degradation of Municipal Solid Waste in Landfills

A first-order kinetic model for the simultaneous anaerobic–aerobic degradation of municipal solid waste (MSW) is presented in the study. The model incorporates the effect of oxygen concentration on anaerobic degradation, enabling the coexistence of anaerobic and aerobic processes within specific oxygen ranges. The model can thoroughly consider the impacts of temperature, moisture content, oxygen concentration, and free air space (FAS) on the degradation rates of five substrates, i.e., holocellulose, non-cellulosic sugars, proteins, lipids, and lignin. The model was successfully verified against two experimental results. The sequential model underestimates both compression strain and degradation ratio, with peak underestimation ratios of 8.7% and 9.2%, respectively. Using the simultaneous model, the effects of anaerobic age, temperature, and aeration rate on landfill aerobic remediation efficacy are quantitatively assessed. Two evaluation criteria, namely the advance rate of aerobic remediation stabilization time (Rt) and the degradation rate after 100 days of aerobic remediation (λ100a), are adopted. The results indicate the following: (1) Rt is more sensitive to anaerobic age and temperature, while λ100a is more affected by anaerobic age and aeration rate; (2) under optimal conditions, Rt and λ100a can reach 86.3% and 70.9%, respectively. The present model provides a crucial theoretical framework for evaluating aerobic remediation effectiveness in both anaerobic sanitary landfills and informal landfills, offering valuable insights for practical implementation and management.

ENVIRONMENTAL ASPECTS OF WASTE-DERIVED BOTTOM BLEND CLAY LINERS INCORPORATING ZEOLITE AND BENTONITE

This research investigated the effects of incorporating bentonite and zeolite into bottom blended clay liners (BBCLs) on their engineering properties and adsorption capacity. BBCLs composed of clay, water treatment residue, and calcium carbide in a 40:40:20 ratio by volume were investigated with the addition of 1, 2, and 3 wt.% bentonite or zeolite. The experimental results indicated that bentonite and zeolite had positive effects on the slake durability index and the equilibrium time for the adsorption of lead (Pb) and chromium (Cr) from the leachate, whereas the unconfined compressive strength (UCS) and coefficient of permeability were negatively affected compared to those of the samples without bentonite and zeolite. At 56 days, the UCS of BBCLs with bentonite and zeolite decreased from 3.4 to 2.2MPa, while the coefficient of permeability of all the samples met the regulatory limit of sanitary landfills, which was given at 1×10-7cm/s. The slake durability index of all samples was lower 50% but it remained higher compared to BBCLs without bentonite and zeolite (approximately doubled). Both additives enhanced the equilibrium time and percentage of Pb and Cr adsorption by about 20% and 200%, respectively. SEM-EDS results show the adsorption of Pb and Cr onto the raw materials, calcium silicate hydrate (CSH), zeolite, and bentonite. Therefore, the addition of zeolite can increase the ability to adsorb heavy metals form leachate, which is suitable for use in secured landfills.

Municipal Solid Waste Management System: A Study of Aligarh City, Uttar Pradesh, India

Municipal solid waste management (MSWM) is a significant environmental challenge in Indian cities, including Aligarh. Inadequate handling of municipal solid waste (MSW) poses risks to public health and the environment. Studies indicate that approximately 90% of MSW in India is improperly disposed of in open dumps and landfills, leading to various ecological and health issues. A detailed examination of Aligarh's waste management system was conducted to assess the quantity, characteristics, and sustainable management options for its municipal waste. Findings from the study show that private collectors handle about 430 tons of waste per day in Aligarh, but neither residents nor collectors engage in waste segregation at the source. The combined collection efficiency of A2Z Private Limited and the Aligarh Municipal Corporation is estimated to be around 70%. Due to the high organic content in the waste, its energy potential remains untapped. Currently, about 80% of the collected waste is disposed of in open dumps, as Aligarh lacks a sanitary landfill. This study highlights the current state of municipal solid waste management in Aligarh focusing on the quantity, quality, and management strategies in Aligarh. Methodology: For this study, Aligarh, a medium-sized city with a population of roughly 8.7 lakhs, which is located 130 kilometres from Delhi, India's capital, was chosen. A thorough assessment of the literature was done to create a theoretical framework. Visits to fields were carried out to gather basic data and comprehend the city's SWMS, including interaction During interviews with several municipality employees and executives in charge of SWM and citizens of the city. A procedure was created to examine the sources, calculate the amounts, and ascertain the waste streams' makeup. Findings: Despite their best efforts, the local municipality's limited resources do not allow for the effectiveness of the solid waste management system in Aligarh. On the outskirts of the city, waste is frequently disposed of in open or low-lying regions without using the correct scientific or engineering techniques.

THE APPLICATION OF CHOICE MODELLING FOR A SANITARY LANDFILL IN KOTA BHARU, KELANTAN, MALAYSIA

Environmental impacts from poor landfilling practices have long been a concern in Kota Bharu, a densely populated city in Peninsular Malaysia. Addressing this issue requires a sustainable disposal solution, such as a sanitary landfill. However, such a project can fail without understanding household demand. This study examined households' willingness to pay for a sanitary landfill using a survey-based method known as Choice Modelling. This method was employed to determine households' willingness to pay for the environmental benefits of a sanitary landfill, characterized by attributes like controlled leachate discharge, reduced bad odour, reduced disease vectors, and pleasing views. The results indicated a positive willingness to pay for each attribute, ranging from RM2.37 to RM12.08 per month. This information aids policymakers in making decisions that align with household demands, thereby minimizing opposition and enhancing project feasibility.

Integrated approach of waste analysis and life cycle assessment for the management of non-recyclable plastics in recycling shops

The unbound usage of plastic products in modern society has brought convenience and poses significant environmental challenges. Recycling Shops (RS) are vital in mitigating plastic waste problems in urban waste management. During the recycling process, RS generates non-recyclable plastics that demand scientific solutions for its management. This study conducted material flow analysis (MFA) to estimate the yearly recycled plastic waste in the RSs of Khulna City. Subsequently, a life cycle assessment (LCA) was performed to explore the suitable management facilities for non-recyclable plastics. The results highlighted the contribution of the informal plastic recycling sector to the city's waste management system by recycling 6324 tons of plastic waste per year. Polypropylene (PP) and Polyethylene (PE) were the most abundant polymers among the recycling plastics in RS. The LCA results revealed that among the five considered cases, Open Burning showed the maximum impact on the environment while Sanitary Landfill exhibited the lowest environmental impact across eighteen impact categories. The sanitary landfilling of non-recyclable plastics was identified as an environmentally friendly approach for managing non-recyclable plastics. This study addressed the urgency for appropriately managing non-recyclable plastics to protect the human and environment from plastic pollution in Bangladesh including recommendations for improving current practices.

An integrated GIS-MCDM framework for zoning, ranking and sensitivity analysis of municipal landfill sites

ABSTRACT This study introduces a comprehensive Geographic Information System – Multi Criteria Decision-Making (GIS-MCDM) framework to identify and evaluate potential municipal landfill sites in Nashik, India. The approach integrates topographic, geomorphological, environmental, and infrastructure criteria to create thematic raster layers representing suitability for landfill development. Criteria include ground slope, elevation, land use, proximity to water bodies, land value, and infrastructure proximity. The Analytical Hierarchy Process (AHP) was employed to determine the relative weights of these criteria, facilitating the computation of the Landfill Suitability Index (LSI) and the creation of a suitability map. The analysis classified the 480 sq. km study area into five categories, with 6.79% of the area deemed “Very High” suitability. The TOPSIS method ranked 16 potential sites within high-suitability regions, identifying L10 near Adagaon as the most optimal site. Sensitivity analysis confirmed the stability of site rankings under various weight adjustments, providing robust tool for evidence-based landfill site selection.