Landfill Conditions Research Articles

Role of bio-chemical scale interactions in the Co-landfill of municipal solid waste and bottom ash.

Co-landfill of municipal solid waste (MSW) and bottom ash (BA) has accelerated the scaling of the leachate collection systems (LCS). The matrix of biofilm formation and mineral deposition makes the scaling process in LCS more complicated. However, the fate of metals released from BA and the role of microorganisms in the leachate, which determine the chemical and biological scaling, are not well understood; the scale adsorption ability is little discussed. We analyzed the microorganism response and scale properties under various simulated landfill conditions with different MSW to BA ratios. The adsorption ability of the scales was evaluated through ultrasonic treatment. Scale characterization revealed that Ca2+ plays different roles with co-landfilled BA. Under BA-only landfilling conditions, Ca2+ was precipitated as CaCO3, with a strong adsorption ability. The co-landfilling of BA and MSW resulted in the formation of a thicker scale compared to BA landfilling alone. Interestingly, the hydrophilic surface of the biofilm enhanced the descaling efficiency, achieving up to 85%. Microbial composition analysis at the genus level revealed that the co-landfilling with BA significantly influenced the microbial community. Particularly, BA enhanced the biofilm formation ability of the microorganisms. Additionally, the scales adhering to polyvinyl chloride (PVC) pipes developed a distinct microenvironment different from the leachate, with a noticeable increase in anaerobic bacteria. These findings offer new insights into scale control and pipeline failure caused by aging and corrosion.

Exploring landfill conditions: analyzing relationships among waste composition, leachate water quality, and microbial community structure in inert-waste landfill sites

Exploring landfill conditions: analyzing relationships among waste composition, leachate water quality, and microbial community structure in inert-waste landfill sites

Joint interpretation of magnetic, transient electromagnetic, and electric resistivity tomography data for landfill characterization and contamination detection

AbstractGeophysical techniques have become increasingly crucial for characterizing landfills, offering noninvasive methods for subsurface exploration and contamination assessment. In this study, an integrated geophysical approach—utilizing magnetic, electrical resistivity tomography (ERT), and transient electromagnetic (TEM) surveys—was employed to characterize the Weidenpesch landfill in Cologne, Germany and assess potential groundwater contamination. The results from these methods were consistent, effectively delineating the landfill boundaries and identifying possible contamination. The waste body was distinguished by its relatively low resistivity values with an average value of 1–10 Ω·m in the western and central parts of the landfill and 20–50 Ω·m at its eastern part in contrast with the surrounding high-resistivity gravelly sand layer (several hundreds of Ω·m), and a depth of up to 15 m. The variability in conductivity and magnetic susceptibility across different landfill sections indicated the heterogeneity of buried materials. Additionally, the ERT and TEM data indicate low resistivity values (below 5 Ω·m) at depths of 20–25 m. A correlation with the borehole data suggests that this may represent a contaminated coal/clay layer. Furthermore, repeated TEM measurements revealed significant variation in subsurface conductivity over time, highlighting the need for continuous monitoring. This study demonstrates the effectiveness of an integrated geophysical approach for providing a comprehensive understanding of subsurface landfill conditions, which is essential for informed environmental management and remediation.

Release of Volatile Per- and Polyfluoroalkyl Substances from Plant Fiber-Based Food Packaging and Municipal Solid Waste to Gas under Simulated Landfill Conditions.

Per- and polyfluoroalkyl substances (PFAS) have been detected in plant fiber-based food packaging and most such packaging is disposed in landfills. The objective of this research was to evaluate the release of volatile PFAS to the gas-phase from PFAS-containing, single-use food packaging materials and from municipal solid waste (MSW) during anaerobic decomposition under simulated landfill conditions. After screening 46 materials for total F and 6:2 fluorotelomer alcohol (FTOH), packaging materials were classified as high or low F. High F materials included microwavable popcorn bags, natural plates, compostable bowls, biodegradable boxes, bagasse containers and eco-friendly plates, while the low F materials tested were paper plates, eco-friendly food trays and poly coated freezer paper. Summed PFAS release from the high F materials was 62-800 ng PFAS/g sample and 6:2 FTOH comprised 96.8-99.9% of the summed PFAS. The low F materials and MSW released 0.1-0.4 ng summed PFAS/g sample and 7:2-secondary (s) FTOH was the dominant volatile PFAS. PFAS were generally released early in the 123-285-day decomposition cycle, suggesting that some PFAS will be released prior to the installation of landfill gas collection systems. Nonetheless, PFAS have been reported in collected landfill gas, indicating that release occurs over many years.

Biocomposites Based on Polyethylene/Ethylene–Vinyl Acetate Copolymer/Cellulosic Fillers

This work studied biocomposites based on a blend of low-density polyethylene (LDPE) and the ethylene–vinyl acetate copolymer (EVA), filled with 30 wt.% of cellulosic components (microcrystalline cellulose or wood flour). The LDPE/EVA ratio varied from 0 to 100%. It was shown that the addition of EVA to LDPE increased the elasticity of biocomposites. The elongation at break for filled biocomposites increased from 9% to 317% for microcrystalline cellulose and from 9% to 120% for wood flour (with an increase in the EVA content in the matrix from 0 to 50%). The biodegradability of biocomposites was assessed both in laboratory conditions and in open landfill conditions. The EVA content in the matrix also affects the rate of the biodegradation of biocomposites, with an increase in the proportion of the copolymer in the polymer matrix corresponding to increased rates of biodegradation. Biodegradation was confirmed gravimetrically by weight loss, an X-ray diffraction analysis, and the change in color of the samples after exposition in soil media. The prepared biocomposites have a high potential for implementation due to the optimal combination of consumer properties.

LANDFILL MINING IN THE FRAMEWORK OF INTEGRATED WASTE MANAGEMENT: CASE STUDY OF AN ITALIAN LANDFILL

A remediation project involving landfill mining (LFM) was designed and is ongoing at the 40-year-old Villadose landfill in Rovigo, Italy. The original natural clay lining the bottom of the old landfill is being recovered and used as technical material. Meanwhile newly constructed landfill sectors, designed to contained more than four times more waste than previously are being filled with both excavated waste and fresh municipal solid waste. A laboratory scale experiment was conducted to simulate the expected landfill conditions and analyse the effects of different waste fractions on emissions. The fresh municipal waste although pretreated at a mechanical biological treatment plant shows a significant residual emission potential, in terms of TOC, and NH4. A landfill housing such quality of waste would not be expected to have achieved final storage quality by the end of its aftercare life. The joint disposal of this waste fraction and the substantially degraded excavated waste may contribute to shortening this timeline. This paper reports the landfill mining operation, an assessment of the emissions from the landfill simulation reactors and the implications for the expected landfill behaviour.

Using a combination of δ13CDIC-DOC-difference in dissolved inorganic and organic carbon, δ2H, and δ18O to localize leachate leaks at landfill sites in China

The investigation of leachate leakage at numerous landfill sites is urgently needed. This study presents an exploration of environmental tracing methods using δ2H and δ13C-difference in dissolved carbon (δ13CDIC-DOC) to localize leachate leak points at landfill sites. δ2H, δ13CDIC, δ13CDOC, δ18O, and an array of physicochemical indices (e.g., total dissolved solids, temperature, and oxidation reduction potential) were monitored in both leachate and groundwater from different zones of a landfill site in China during the year of 2021–2023. Moreover, data for these parameters (i.e., the isotopic composition and physicochemical indices) from twelve published landfill cases were also collected, and these groundwater/leachate data points were located within 1 km away from the landfill boundary. Then statistical analyses, such as Pearson correlation analysis and redundancy analysis (RDA), were performed using both the detected and collected parameters at landfill sites. Consequently, the intensity of interaction between leachate and background groundwater was found to significantly control the isotopic fractionation features of hydrogen and carbon, and both the content of major contamination indicators (total dissolved solids, chemical oxygen demand, and ammoniacal nitrogen) and the oxidation reduction potential were the key impact factors. Accordingly, the water type used to indicate leachate leakage points was determined to be leachate that significantly interacted with the background groundwater or precipitation (LBGP). δ2H showed a perfect linear correlation (0.81 ≤ r2 < 1.0) with δ13CDIC-DOC in leachate under highly anaerobic landfill conditions, and the δ2H &δ13CDIC-DOC combinations in the LBGP were significantly different from those in the other water types. For groundwater with total dissolved solids lower than 1400 mg/L at landfill sites, a strong positive linear correlation (r = 0.83) was revealed between δ13CDIC and δ13CDOC. Based on these insights, δ2H versus δ13CDIC-DOC plots and RDA using δ2H and δ13CDIC-DOC as response variables were proposed to localize leak points at both lined landfills and leachate facilities. These findings further understanding of the isotopic fractionation features of hydrogen, carbon, and oxygen and provide novel environmental tracer methods for investigating leachate leak points at MSW landfill sites.

Detection of Leptospira sp. Bacteria and Factors Related to the Incidence of Leptospirosis in Semarang City

Objective: The Case Fatality Rate (CFR) of Leptospirosis in Semarang City has shown a tendency to increase from 2019 to 2022. In 2022, there were 30 cases reported, with 8 deaths (CFR 27%). The purpose of this study was to detect Leptospira sp. bacteria in rats and analyze the risk factors for leptospirosis in Semarang City.Methods: This study employed an observational approach with a Case-Control Study design. The research was conducted in Semarang City from November to December 2023. Non-random sampling techniques were used, specifically the total sampling method, resulting in a sample size of 45 case groups and 45 control groups. Bivariate analysis was performed using the Chi-square test, with a significance level set at &lt;0.05.Results: Based on the Chi-Square test results, the following variables were found to be associated with the incidence of leptospirosis in Semarang City: the presence of rats (p&lt;0.0001), the presence of Leptospira sp. bacteria (p&lt;0.0001), house conditions (p=0.260), sewer condition (p&lt;0.0001), presence of pets (p=0.001), condition of landfills (p=0.001), presence of vegetation (p=0.005), temperature (p=0.299), humidity (p=0.495), lighting (p=0.023), history of wounds (p=0.001), and knowledge level (p=0.025).Conclusion: The risk factors for leptospirosis in Semarang City include the presence of rats, the presence of Leptospira sp. bacteria, sewer conditions, the presence of pets, conditions of landfills, the presence of vegetation, lighting, history of injury, and level of knowledge.

Petrophysical Relationship between Soil Moisture Content and Dielectric Permittivity for Wastewater Landfill Contaminated in Cherang Hangus Soil Using GPR

This study focuses on the dielectric permittivity of Cherang Hangus soil, a laterite type known for its water retention and landfill liner applications. By leveraging GPR data alongside empirical models, researchers aim to understand how moisture content influences dielectric permittivity, which is critical for managing wastewater migration in various soil types. The methodology involves simulating landfill conditions using a concrete tank filled with Cherang Hangus soil and solid waste, allowing for detailed monitoring of moisture and GPR scans. The study employs various regression models to predict dielectric permittivity based on moisture content, including linear, logarithmic, and polynomial approaches. Results indicate that more complex models, particularly the third-order polynomial, provide better accuracy in capturing the relationship between moisture content and dielectric permittivity, as evidenced by high R² 0.9883 for 3rd order regression model for Cherang Hangus. The findings underscore the significance of soil composition in predicting dielectric permittivity, highlighting that the high gravel content in Cherang Hangus soil affects moisture retention and, consequently, the accuracy of empirical models.

A review of toxicity assessment procedures of solar photovoltaic modules

Environmental management of solar photovoltaic (PV) modules is attracting attention as a growing number of field-operated PV modules approach end of life (EoL). PV modules may contain small amounts of toxic metals, and the procedures for assessing and regulating the toxic metal content and release of such materials at EoL differ widely across nations. This paper provides an overview of the metal composition of PV modules and common procedures for toxicity assessment through extensive research and review of technical literature and legislative documents. This review focuses on three primary aspects: first, it explores the distribution of toxic elements within current and emerging PV module designs, with a specific focus on obtaining representative samples for proportional toxicity testing within different module laminate areas. Second, it examines a sampling standard and the diverse toxicity testing methods and regulations employed in various regions, encompassing standards like the Environmental Protection Agency (EPA) Test Method 1311 (Toxicity Characteristic Leaching Procedure, TCLP) in the U.S., Restriction of Hazardous Substances (RoHS) in Europe, and the Waste Extraction Test (WET) in California. Third, the review examines the sources of variability in toxicity testing outcomes, including techniques for securing homogeneous samples from non-uniform PV modules, selecting particle sizes representative of landfill conditions in extracted samples, determining appropriate leachate characteristics such as leaching agents and pH levels, and considering factors like test duration and temperatures. In summary, this review summarizes relevant regulations and offers a comprehensive overview of the strengths and limitations associated with several toxicity assessment procedures currently in practice.

Assessing construction and demolition wood-derived biochar for in-situ per- and polyfluoroalkyl substance (PFAS) removal from landfill leachate

With regulations for per-and polyfluoroalkyl substances (PFAS) impending, the abundance of these chemicals of emerging concern in municipal solid waste (MSW) landfill leachate increasingly challenges landfill operators to seek on-site leachate pre-treatment options. This two-staged study explores the potential reuse of biochar derived from construction and demolition debris (CDD) wood as an in-situ PFAS sorbent for application within MSW landfill leachate collection systems. Batch leaching tests were first used to examine the feasibility of capturing PFAS from landfill leachate using two sources of CDD-wood-derived biochar. Then, columns were used to test the in-situ sorption capabilities of the same biochars under simulated landfill conditions. All leachates were characterized for pH, chemical oxygen demand, ammonia-nitrogen, and 92 PFAS. Seventeen PFAS were detected in the batch leaching experiment, and nine PFAS were detected in column leachates. In the batch leaching scenario, Biochar 1 achieved a maximum of 29% PFAS reduction compared to controls. Columns containing Biochar 1 generated leachates with PFAS concentrations 50% to 80% higher than those in control columns for the duration of the experiment. Columns containing Biochar 2 generated leachates with PFAS concentrations 44% less than controls in week 1 and similar concentrations in weeks 2, 3, and 4. In this study, PFAS removal from landfill leachate using biochar derived from CDD wood was not significant. Further research on biochar derived from CDD wood is needed before it can be recommended as an in-situ landfill leachate pre-treatment method.

Comprehensive analysis of the performance of welding joints of gas pipelines with different viscosities

Full-scale tests of gas pipelines with different viscosities were carried out in landfill conditions, which are as close as possible to the natural conditions of operation of gas pipelines. The kinetics of crack propagation along welded joints - their trajectory, the transition from the weld seam to the base metal of the pipe and vice versa, the speed of movement of cracks in viscous and brittle metal and defined zones of plastic deformation - were experimentally investigated. It is known that tests on Menaget, Charpy and other samples, which have thicknesses that do not correspond to the thickness of the pipe walls, do not reflect the real picture of visco-plastic and brittle fractures, which does not allow to develop a methodology or model for predicting the final resource (non-accident) of long-term gas pipelines period of operation. At the same time, theoretical and laboratory researches do not always adequately answer the questions directly related to ensuring the durability and trouble-free operation of pipelines. It is likely that in the laboratory conditions of enterprises or scientific institutions it is difficult to reproduce and take into account all the factors that characterize the growth and spread of destruction in a real operating gas pipeline. Therefore, the data of laboratory studies must be checked and necessarily clarified according to the results of pneumatic tests of long pipe sections, i.e., at present, the need to combine laboratory and field tests of pipes of the gas pipeline network is urgently needed. Such tests are not massive, but as a result of their performance, important information is obtained regarding the behavior and properties of the metal in the conditions of loading and operation, which are closest to operational conditions. In field tests, pipes with a diameter of 1000x18 mm were used, which underwent controlled rolling (steel class X70 - grade 06G2BA) at a working pressure of RR = 9.7 MPa (in the northern - low-temperature version). Tensile tests, studies of impact toughness, strength and plasticity of the weld metal were carried out according to standard methods described in works [2-5]. During the experiments, a large number of sensors of temperature, pressure, strain, stress, crack propagation speed, etc. were used. The obtained results regarding the kinetics of the destruction of natural pipes in landfill conditions lay the groundwork for the development of a mathematical model of the engineering forecast of the residual (non-accident) resource of pipelines operating in oil and gas fields.

Evaluation of bioplastics biodegradation under simulated landfill conditions.

Bioplastics that are generated from renewable sources have been regarded as an alternative to conventional plastics. Polylactic acid (PLA) is one of the mostly produced bioplastics because of its long shelf life for various applications. Even though bioplastics have drawn attention recently, their ultimate fate in landfills is still unknown. In this study, a standardized laboratory-scale lysimeter experiment was performed for the simulation of landfill conditions in order to evaluate the biodegradability of PLA during municipal solid waste stabilization. The reactors were loaded with municipal solid waste (MSW) taken from an operating landfill, certified PLA cups, and seed sludge. Various phases of landfill stabilization were simulated; hence, the reactors were operated under aerobic, semi-aerobic, and anaerobic conditions, respectively. Throughout the operation, both leachate and biogas generation in the reactors were regularly monitored. At the end of each phase, bioplastic cups were removed from the reactors, gently cleaned, weighed, and examined under a scanning electron microscope (SEM). The experimental results indicated that bioplastics did not undergo significant biodegradation during the first two stabilization phases (aerobic and semi-aerobic). On the other hand, it was observed that the cups were much softer and whiter at the end of the anaerobic phase. The weight of cups decreased by 12.8% on average, and their surfaces were prominently damaged after the completion of the last phase indicating the potential signs of biodegradation.

Application of high-dimensional uniform manifold approximation and projection (UMAP) to cluster existing landfills on the basis of geographical and environmental features

Due to extreme conditions, which are influenced by the location of landfills, the release of pollutants has been recently proven to be more severe in estuary landfills, as these landfill locations are affected by both sea-water and river-water interactions. To identify geographic and environmental features linked to the extreme conditions of certain landfills, a high-dimensional clustering method combining Uniform Manifold Approximation and Projection (UMAP) with the Louvain algorithm is proposed.A case study was conducted using 17 noteworthy features that transform to Landfill Suitability Index (LSI) applied to hundreds of landfill sites in Taiwan. This study clustered landfills into 10 clusters and identified several clusters with significant extreme locations, including estuary landfills (7.9 %), fault-water-body landfills (8.2 %), and densely-populated-water-body landfills (17.6 %). Furthermore, a critical discovery of endangered Platalea minor habitats near these estuary landfills was made. Additionally, this work identified “healthy” landfills (11.2 %) that are minimally affected by the considered features. These findings demonstrate the promising potential of our framework for managers to systematically improve landfill management strategies. Moreover, our framework was tested by incorporating rainfall and flooding features in relation to climate change scenarios. To address the demand for land release from occupied landfills in Taiwan, there is a pressing need to expedite the transition to a circular economy, and our framework can provide further assistance in this regard. This approach is promising, as it provides a new method to evaluate the environmental risks linked to landfills and also identifies potential opportunities related to landfill mining.Finally, this work was extended to include a case study in England, which has 19,801 landfills and a dataset containing 15 relevant landfill features; in this case study, our framework identified 110 landfill clusters, and several placed in extreme locations, demonstrating that our framework is flexible for use in other regions outside of Taiwan.

Chemo-Mechanical Behavior of Bentonite-Sand Mixtures Inundated with Organic Pore-Fluid

ABSTRACT Bentonite-sand mixture is considered to be a potential liner material for landfill facilities owing to its excellent sorption potential and swelling characteristics. Such liner materials are expected to perform satisfactorily if the hydraulic conductivity is maintained less than 10−7 cm/s and thereby inhibiting the migration of the generated leachate. However, the performance assessment of these liners in the presence of highly concentrated organic fluids and under the overburden stresses that is usually expected in landfill conditions is scarce. Therefore, in the present work, the hydraulic performance of the bentonite-sand mixtures in the presence of the organic compounds commonly encountered in the landfill leachate is studied, which is a need of the hour. Flow tests were performed to evaluate the hydraulic conductivity of different bentonite-sand mixtures in unhydrated conditions and permeated with varied proportions of methanol-water and ethanol-water mixtures. The study reveals that the proportions of the organic pore fluids significantly influence the hydraulic conductivity of the bentonite-sand mixtures. A very good linear relationship was observed between the pore fluids’ dielectric constants and the hydraulic conductivity of the bentonite-sand mixtures. The chemo-mechanical behavior suggests that the conventional bentonite-sand mixtures perform poorly in terms of the hydraulic and swelling characteristics with the change in the dielectric constant of the organic fluids. The microstructural analysis also supports the experimental findings that as the dielectric constant of the fluid are reduced, the effective flow path through the soil increases considerably resulting in higher hydraulic conductivity.

Investigation of Long-Term Behaviors of Solidified/Stabilized Hazardous Waste Under Different Landfill Conditions

Investigation of Long-Term Behaviors of Solidified/Stabilized Hazardous Waste Under Different Landfill Conditions

Hydraulic Conductivity Characteristics of Iron-Ore Tailings–Bentonite Mixtures Exposed to Landfill Leachate

Landfill liner materials are required to provide reliable hydraulic performance for very long times after construction, and at least for the design lifespan of the facility. To meet this objective, liner systems must retain their low hydraulic conductivity over their service lives. In this paper, we report on the durability aspects of iron-ore tailings (IOT)–bentonite mixtures in extended hydraulic conductivity experiments. The hydraulic conductivity tests were conducted on mixtures containing 20%, 25%, 30%, 35%, and 40% bentonite, compacted at 2% wet of optimum by the British standard light (BSL) effort, and permeated with municipal solid waste (MSW) landfill leachate (electrical conductivity = 25.60 mS/m, pH = 7.94) with or without prehydration for a duration of 120 days. Under these influences, permeation with leachate showed no detrimental effect on mixtures with 25% and 30% bentonite, but was rather beneficial in reducing the hydraulic conductivity (k) values of the two mixtures at the end of testing by two orders of magnitude to 4.19 × 10−8 and 9.25 × 10−9 cm/s for the prehydrated specimens and 2.4 × 10−8 and 9.9 × 10−9 cm/s for the nonprehydrated specimens. For mixtures containing 20%, 35%, and 40% bentonite, k values representing a 1.6 times decrease from the average were recorded for both the prehydrated and nonprehydrated conditions at the end of testing. Further analysis showed that prehydration had a slightly substantial effect on those specimens containing 20%, 35%, and 40% bentonite, whereas it had a minor effect, if any, on mixtures with 25% and 30% bentonite. In terms of durability, only mixtures containing 25% and 30% bentonite that consistently maintained low k values up to the end of testing are projected to be effective as liner materials in the construction of geological repositories for MSW. Regarding the hydraulic conductivity characteristics of the mixtures upon exposure to the combined effects of leachate and the elevated temperatures expected in landfill conditions, all mixtures maintained relatively good hydraulic performance, exhibiting a decrease in hydraulic conductivity with time.

Exploring into a light-avoided environment: Mechanical-thermal coupled conditions responsible for the aging behavior of plastic waste in landfills

Plastics in landfills undergo a unique micronization process due to multi-factor and light-avoided conditions, but their aging process in such a typical environment remains unexplored. This study investigated the aging behavior of polyethylene plastics, representative of landfills, under simulated dynamic mechanical forces and high temperature—two prevalent environmental factors in landfills. The study explored the individual and combined contributions of these factors to the aging process. Results indicated that high temperature played a primary role in aging plastics by depolymerization and degradation through ·OH production, while mechanical forces contributed mainly to surface structure breakdown. The combined effect leads to more serious surface damage, creating holes, cracks, and scratches that provide access for free radical reactions to plastic bulk, thereby accelerating the aging and micronization process. The resulting microplastics were found to be 14.25 ± 0.53 μg L−1. Aged plastics exhibit a rapid aging rate of depolymerization and oxidation compared to virgin plastics due to their weak properties, suggesting a higher potential risk of microplastic generation. This study fills a knowledge gap regarding the aging behavior of plastics under complex and light-avoided landfill conditions, emphasizing the need for increased attention to the evolution process of microplastics from aged plastic waste in landfills.

Extended Producer Responsibility for Waste Management Policy

Solid waste management, which always ends in landfills, causes various environmental and socio-economic impacts. Tegal City also experiences overcapacity landfill conditions because the waste management model focuses on landfills. This study aims to identify existing waste management regulations and how EPR can become a policy framework to achieve waste management beyond landfills. The result explains that by regulation, the government has regulated the flow of solid waste management by prioritizing the 3R principles, starting from the transportation process, sorting at TPS/TPST, and even processing to become a product with economic value. However, in the end, all this waste still ends up in landfill. From the government's perspective, this is due to the need to integrate responsibilities between the government, society, and producers. Producer responsibility must be fully implemented in waste management. However, several regulations have yet to regulate the form of waste management that producers can carry out the responsibility of producers as specifically to be responsible for the product until it ends up as waste. In addition, this study illustrates that EPR as a policy framework for waste management can be applied in other cities, primarily if the government's point of view supports the division of responsibilities for waste management.

Utilization of methane from municipal solid waste landfills

Here, we analyzed the utilization efficiency of methane (CH&lt;sub&gt;4&lt;/sub&gt;) gas from landfill sites associated with its power generation potential in different systems; in addition, we analyzed the reduction in the amount of CH&lt;sub&gt;4&lt;/sub&gt; emitted from landfills of untreated waste, proposed an effective method for site selection, and investigated the environmental issues caused by landfilling solid waste. Furthermore, we evaluated the geographical and chemical characteristics, iteration variables of landfill operations, application of CH&lt;sub&gt;4&lt;/sub&gt;, efficiencies of energy-converting systems, and reduction in the CO&lt;sub&gt;2&lt;/sub&gt; emissions from other energy sources, with the landfill gas (LFG) being considered as the fuel. For efficient and quality extraction of CH&lt;sub&gt;4&lt;/sub&gt; from LFG, we investigated the ideal landfill conditions (e.g., construction, geometry, weather, temperature, moisture, pH, and biodegradable matter) and hydrogeological parameters that influence the generation of LFG and landfill leachate. The first order decay equation was used to predict the CH&lt;sub&gt;4&lt;/sub&gt; generation from a single bulk municipal solid waste stream for various characteristic interims of geography and CH&lt;sub&gt;4&lt;/sub&gt; generation capacity and potential. More CH&lt;sub&gt;4&lt;/sub&gt; is generated in the conventional clean air act condition than wet and arid conditions. Based on the analysis, we suggest efficient and economical power generation systems for using the CH&lt;sub&gt;4&lt;/sub&gt; emissions from landfills.