Waste Disposal In Landfills Research Articles

Experimental reduction of landfill emissions based on different concepts: the paf model

A laboratory column test and a large lysimeter reactor were set up to simulate thebehaviour of MBP waste disposal in different concept landfills. In particular, threedifferent options were used to study the reduction of long term environmental impact andto reach the sustainability: mechanical-biological pretreatment waste disposal, natural andforced aeration and flushing. The lab-scale test was set up to compare the differentbehaviour of waste with anerobic, aerobic and semiaerobic conditions, flushing. Thelysimeter reactor simulated the combination of the three different options (PAF model).The results presented in this paper show that this combination seems to synergize thepositive effects in terms of leachate and gas emissions.

In-situ fabrication of ZnO thin film electrode using spent Zn–C battery and its electrochemical performance for supercapacitance

In consideration of effective supercapacitors which are also affordable and lightweight, metal oxides can be considered because of the higher charge storage capability. This work establishes the in situ fabrication of a supercapacitor electrode, employing spent Zn–C batteries as precursor. Every year, extensive number of waste batteries including Zn–C battery end up in landfill, which prolonged the compulsion of waste disposal in landfill and creates environmental and health threat. The transformation of waste battery materials into fabricating components for energy applications, is of great significance for sustainable strategies but it is a challenging work to produce nanomaterials with purity by green methods. The present study proposes the in situ fabrication of ZnO NPs as ultra-thin film on a porous silicon (P-Si) substrate from spent Zn–C battery at 900 °C in the horizontal tube furnace under argon atmosphere. The particles were around 45 nm size and semi-spherical in morphology and showed uniform distributions all over the substrate as a discrete ultra-thin film. The ZnO ultra-thin film basically comprised of several ZnO film layer which stacked with each other periodically and made one thin layer of ~ 390 nm, where the single layer was ~ 45 nm. Formation of ZnO NPs were detected by the analysis of XRD, EDS and XPS. Using cyclic voltammetry as well as impedance spectroscopy in 0.6 M KOH as electrolyte, electrochemical properties of developed electrodes and supercapacitor have also been examined. The ZnO/P-Si electrode demonstrated a highest value of specific capacitance 547 F g−1 at 5 mV s−1 scan rate. Obtained results demonstrate that spent Zn–C battery can be selected to fabricate the energy storage devices which can offer economical, technological and environmental advantages.

Detection of waste dumping locations in landfill using multi-temporal Landsat thermal images.

The disposal of solid waste in a conventional landfill is inevitably associated with potential adverse environmental impacts, resulting in the migration of landfill gas and offensive odors on the surrounding areas. In addition to the obnoxious fumes and hazardous leachate, heat generation is continuously observed within the landfill during the aerobic and anaerobic phases. Despite the negative impacts, such "heat generation" phenomenon can turn into valuable information to aid in detecting unauthorized landfill activities and tracing unrecorded dumping regions. The spatial distribution of waste buried under the ground can be approximated and revealed through measuring the ground surface heat flux. In this study, we demonstrate how to utilize thermal remote sensing techniques to measure the land surface temperature (LST), which can aid in outlining the waste dumping regions within a landfill. The Jeleeb Al-Shuyoukh landfill, located in Kuwait, was used to demonstrate the proposed method, where the record of the exact dumping location was missing during the Gulf war. Ten-year Landsat Thematic Mapper(TM)/Enhanced Thematic Mapper Plus (ETM+) images (1985-1994) were acquired and processed in order to compute the LST within the landfill. Through combining the multi-temporal LST contours and overlay analysis, the most probable dumping regions within the landfill were outlined. A probability map was created to indicate the possible location of waste dumping within the studied landfill. With reference to the 50 boreholes drilled by the Environmental Protection Authority of Kuwait, our results derived during the summer and winter seasons both yielded an overall accuracy of 72%.

Impact of Composting Food Waste with Green Waste on Greenhouse Gas Emissions from Compost Windrows

Windrow composting of green waste as an alternative to green waste disposal in landfills requires an understanding of the impacts on greenhouse gas (GHG) emissions and the development of effective and efficient management strategies to reduce these emissions. The addition of food waste to green waste compost operations is becoming more common, but its effect on GHG emissions is less understood. As more food waste diversion occurs as a result of recent implementation of climate smart policies in California, more information is needed to address the sustainability of composting different combinations of waste types. We monitored GHG emissions from compost windrows comprised of green waste alone and a green/food waste mixture (green waste : food waste = 9:1, by wet weight) at the University of California, Davis Student Farm in 2016 using a modified, open, flow-through chamber technique. When comparing total emissions of nitrous oxide (N2O) and methane (CH4), the green/food waste mixture produced 110 kg CO2 eq./ton DM (dry matter, std error = 12.2), which were slightly lower than emissions produced by the green waste alone (152 kg CO2 eq./ton DM, std error = 15.9). Methane was a large contributor to global warming potential (GWP) of both composting treatments, suggesting that management practices that optimize porosity and air flow in compost piles are promising in reducing emissions from both green waste and green/food waste mixtures.

Assessment of Composting Technologies for Organic Waste Management

Organic waste disposal in landfills has created various environmental issues, such as greenhouse gas emissions and leachate. Awareness of this issue has resulted in diverting landfill to compost. Thus, there is a need to develop an analytical tool to select the best composting technology. Therefore, this paper reviews a range of assessment steps designed to evaluate specific sustainability criteria (environmental, social, economic, and technical) for organic waste management to select the most suitable composting technology. Due to the complexity of conflicting criteria and alternatives in composting technology, a multi-criteria decision-making (MCDM) technique is suggested to ensure the quality of the decision-making process. As an additional benefit, the synthesis results via the MCDM tool will be more credible when seeking validation by stakeholders. © IJTech 2018.

Allocation of sanitary landfill in consortium: strategy for the Brazilian municipalities in the State of Amazonas.

One of the current problems faced by the Brazilian municipalities is the adequate disposal of municipal solid waste in landfills while considering the environmental dimension. In addition to the design and technical requirements, the analysis of possible sites is a process requiring an evaluation of different criteria. With the proposal to minimize and rationalize efforts for site selection, this paper presents a methodology to evaluate its suitability based on certain criteria (legal, technical, environmental). The selection of the most preferable areas for the installation of a landfill is in context of a model for municipal consortium proposed in the State Plan of Solid Waste of Amazonas which applies to the municipalities of Atalaia do Norte, Benjamin Constant, and Tabatinga. The Analytic Hierarchy Process method was combined with geoprocessing tools in order to determine the relative importance of the evaluation criteria while considering the inherent limitations of data availability for the area of study. Thus, based on the participation of expert groups an aptitude map was produced where 47 potential areas were identified as suitable for the installation of a landfill in those municipalities. Among them, the most suitable is located near the highway that connects the municipalities of Benjamin Constant and Atalaia do Norte.

Impact of Indoor Air Quality by Incorporating Agricultural Waste Into Fired Clay Brick

The demand for edible oil from all over the world has generated a huge amount of solid waste. Due to that, the problem of disposal method has become a constraint by the authorities. Therefore, this study is focusing on the incorporation of palm kernel shell (PKS) into fired clay brick in terms of indoor air quality assessment. The brick was incorporated with 0% and 5% of PKS and fired at 1050°C with heating rates of 1°C/min. Preliminary analysis was conducted with X-Ray Fluorescence test to determine chemical composition of raw materials used in the study. A further experiment of indoor air quality was obtained by measuring gases emission of total volatile organic compound (TVOC), carbon dioxide (CO2), carbon monoxide (CO), ozone (O3), formaldehyde (HCHO) and particulate matter (PM10) in Walk in Stability Chamber with controlled temperature and relative humidity. All parameters were compared with Industry Code of Practice on Indoor Air Quality standard. The result shows that incorporation 5% of PKS into fired clay brick complied with the standard requirement for use as building materials. As the conclusion, the use of palm kernel shell as clay replacement could reduce the waste disposal in landfills whilst providing low-cost building materials.

Willingness to pay for higher construction waste landfill charge: A comparative study in Shenzhen and Qingdao, China

High landfill charge presents an effective approach to divert construction waste from landfill. The stakeholders’ willingness to pay (WTP) for the disposal of construction waste in landfill provide the useful information to set a reasonable charge level. Considering the diversity in stakeholder groups and regional socioeconomic conditions, contingent valuation method (CVM) was employed in this study to investigate the WTP of two major stakeholder groups in two typical Chinese cities. In addition, the perception of stakeholders towards landfill charge policy was measured and the impact of various factors on WTP was explored. The results indicated that there were statistically significant disparities of WTP between cities and stakeholder groups. Stakeholders from Shenzhen were willing to pay more than their counterparts in Qingdao. Contractors were willing to pay less than owners. Respondents who evaluate the policy as effective in reducing construction waste landfill were willing to pay more. However, firm size, ownership, position of respondent and perceived equity factors did not show statistically significant effect on WTP. These findings highlight the necessity to customize landfill charge policy according to local socioeconomic conditions.

Hydro-mechanical behavior of a lateritic fiber-soil composite as a waste containment liner

In waste disposal landfill projects, the hydraulic conductivity of the barriers is a major consideration. The use of fibers mixed with backfill may improve the overall performance of the barriers. Fiber-soil composites show a more resistant and ductile behavior than the soil alone. The presence of fibers may reduce cracking problems related to shrinkage or traction in liners or covers. In this study, laboratory tests were performed to evaluate the use of fiber-soil composites as a containing barrier. Hydraulic conductivity and diametral-compression tests were carried out on PET fiber reinforced and unreinforced compacted soil specimens. The tests were conducted under confinement conditions similar to those found in the field. Diametral-compression tests were used to induce cracks in the specimens. Hydraulic conductivity was measured at different stages during the diametral loading. In the tests performed under low confinement pressure (10 kPa), the crack openings led to a significant increase in hydraulic conductivity. The results showed that the addition of fibers increases the tensile strength of the soil-fiber mass and delays the opening of cracks. Moreover, in the tests under high confinement pressure (100 kPa), a decrease in hydraulic conductivity occurred at all stages of the diametral load application.

Criteria for Choosing a Set of Technical Measures to Reduce Emissions on Municipal Solid Waste Landfills

The analysis of technical measures allowing to control the municipal solid waste disposal (MSW) landfill with the purpose of emission reduction at different stages of the life cycle is presented. The review of the latest research in the field of implementation of technical measures at the operational and aftercare period is conducted: controlled water infiltration, collection of biogas, aeration of the landfill body, installation of methane oxidation cover systems. It is substantiated that the choice of a technical measure for management of the disposal for MSW landfill should be carried out taking into account the ultimate goal: reduction of biogas and leachate emissions, acceleration of waste decomposition processes, reduction of the impact of the landfill on environmental objects at the aftercare period. Criteria for choosing technical measures for reduction biogas and leachate emissions, boundary conditions and peculiarities of their implementation at different stages of the life cycle of the landfill have been established.

Does the addition of soil amendments have a positive influence on landfill soils?

Waste disposal in landfills is one of most frequently used methods of municipal solid waste (MSW) management. Landfills disturb to a certain extent the landscape character and disposal of waste in landfils represents one of human activities that may impair natural ecosystems. Due to waste decomposition, numerous chemical, physical and biological reactions and changes occur within the landfill body that give rise to dangerous and harmful substances. One of the problems very often occurring in the landfill surrounding is soil contamination. This study is focused on the assessment of soils contamination due to the operation of sanitary MSW landfill. The aim was to determine the effect of diatomite and compost on soil phytotoxicity. Toxicity was assessed in a pot experiment with soil amendments. Soil samples (sample 1–4) for the experiment were taken from the landfill site (sample 1–3) and its surrounding (sample 4). The aim of this study was to check relation between soil amendments added to the soil sample and the amount of biomass produced by some plant species ( Sinapis alba L., Hordeum vulgare L.). In this study soil amendments improved soil characteristics. The paper shows that a higher percentage of biomass weight increase was recorded in samples 1, 2, 3 and 4 with the addition of compost. As compared with the addition of diatomite, biomass weight in the samples with the added compost increased on average by 67.25%. Therefore, it can be stated that the addition of diatomite did not advance the plant growth as much as the addition of compost. The potential of using soil amendments in practice is promising.

Permeability and Gamma-Ray Shielding Efficiency of Clay Modified by Barite Powder

Environmental protection around radioactive waste disposal is a very important issue for safety purposes. Consequently, permeability and radiation shielding are the two important factors for isolating radioactive disposals. Clay is relatively impermeable soil that is naturally available, cheap and environmentally friendly. In this research, the influence of modifying clay by barite powder was investigated to improve the gamma ray shielding performance while keeping the low permeability of clay soil. This research was conducted using both experimental and simulation methods. In this study, bentonite clay samples with 10%, 20%, 30%, 40%, 60% and 80% of barite powder was prepared to find the optimum percent of barite powder. A HPGe detector was used to measure the attenuation coefficients at commonly used gamma ray energies of 137Cs (661.6 keV) and 60Co (1173.2 and 1332.5 keV) for all the samples. The attenuation coefficients for samples were determined by both simulation method, using the MCNP code, and XCOM database to compare with the experimental results. Simulation results were found to be in good agreements with the experimental results. The obtained results show that with increasing the percent of barite powder, radiation shielding coefficient (µ) increase while permeability coefficient becomes grater. However, according to the obtained results, the bentonite clay with 40% of barite powder is the optimum composition with a permeability factor of 8.87 × 10−11 m/s and attenuation coefficient of 16.46 m−1, 12.2 m−1 and 11.99 m−1 at 661.6, 1173.2 and 1332.5 keV energies, respectively. In addition, the results for clayey soil samples were compared to the concrete mixture. It was found that clay mixture with 40% barite powder would overcome concrete regarding gamma-ray shielding performance. As a result, the clay composite particularly due to its imperviousness and availability, seems to be an appropriate alternative for radiation shielding in radioactive waste disposal landfills.

The use of vegetation as a natural strategy for landfill restoration

AbstractIt is well‐known that the disposal of municipal solid waste in landfills has adverse effects on the environment and human health. Restoration of closed landfills is essential to compensate for disturbances in the ecosystem, minimize negative impact on the environment, and ensure safety in further use. It was hypothesized that specific plant succession knowledge can present nature‐based solutions to restore and rehabilitate degraded ecosystems at municipal solid waste landfills. The goal of the 8‐year study was to identify restoration strategies based on vegetation succession. For the vegetation survey, we recorded the vegetation over the period 2007–2015. The study was carried out on the surface of the landfill site. We also used four mathematical models to analyze the increase of plant species over time. During the study period, 195 vascular plant species were recorded. There was a progressive change in plant communities and an increase in biodiversity. What is more, the growth prediction models show that the diversity of plant species over time at the landfill site has an increasing tendency, which has beneficial implications for landfill restoration. During the vegetation survey period, there was no evidence to suggest that the landfill site had a significant impact on the biotic composition of the environment. We can conclude that the health status of plants occurring in the landfill was good. Plants both contributed to and indicated the health of the landfill site and were found to be a convenient and natural component of landfill restoration.

A Review of the Triple Gains of Waste and the Way Forward for Ghana

The postcolonial waste management practices in Ghana have consistently been identified with the discarding and disposal of waste in open dumps, wetlands, and landfills. These practices have only contributed to the glaring poor sanitation in the cities of Ghana. Insignificant quantity of the waste generated ends up in recycling and/or composting units for reuse. Given the current growth of Ghana’s population, coupled with the emerging industrialisation, the country’s overdependence on hydropower for energy and natural resources for production alone is dangerous. This paper provides a holistic review of the gains from solid waste. The paper reaffirms that, through appropriate technologies, waste possesses the intrinsic potential to generate renewable energy, resources, and income. In recommending, the main objective of waste management practices in Ghana should be about exploring the economic potentials of waste. Thus, waste disposal should be the last resort, and not the first option in waste management practices in Ghana.

Are raw materials or composting conditions and time that most influence the maturity and/or quality of composts? Comparison of obtained composts on soil properties

Abstract Waste composting is a process which is spreading worldwide to reduce waste disposal in landfill. The composting technical currents give little attention to the type and chemical composition of biomass that are mixed not considering that these can affect quality and maturity of the compost produced. In addition, during the composting process the amount of oxygen and temperature are generally only monitored but not set up. Our hypothesis is that composts, prepared from different organic wastes, can be chemically different with consequent different fertilizer properties. Stability and quality of composts are dependent on multivariate parameters such as raw material source, proportions used, composting procedure, and maturation time. Starting from this consideration a composting experiment was carried out to evaluate if were the raw materials (chemical composition, mixture and ratio), or the composting conditions and time, to influence the maturity or the quality of composts. We prepared four composts starting from different combinations and ratios of vegetable residues and/or olive pomace. After 120 days, the four composts were physically, chemically and biologically characterized to evaluate maturity degree, stability and quality of the products obtained under the same composting conditions and time. Their ability, as soil improver, was evaluated assessing soil chemical and biochemical properties 90 days after the compost addition. Here we show that the chemical composition of raw materials and the set up parameters of composting processes can have a different weight in influencing compost stability and quality. Our results evidenced that during the composting process all the composts had a similar percentage of C/N ratio reduction and all of them achieved an acceptable maturity degree. The composts produced by olive pomace showed the highest degree of maturity as demonstrated by T value and organic matter loss, both indices of compost stability. Conversely the composts coming from green vegetable residues were richest in nutrients and phenols and had the highest CSC all indices of better quality. In this work we identified two composts able to increase carbon stock, and water holding capacity parameters that positively influence soil structure, and two compost able to increase the amount of soil microbial biomass, their activity and soil biodiversity, improving soil biological fertility. These results highlighted that compost maturity doesn't mean compost quality, suggesting that compost maturity is mainly linked to composting setup parameters, while compost quality is mainly linked to chemical composition. FDA and DHA activities have been identified as markers for assessing the quality of amended soils.

Experimental Investigation of the Productivity of a Wet Separation Process of Traditional and Bio-Plastics

The separation process within a mechanical recycling plant plays a major role in the context of the production of high-quality secondary raw materials and the reduction of extensive waste disposal in landfills. Traditional plants for plastic separation employ dry or wet processes that rely on the different physical properties among the polymers. The hydraulic separator is a device employing a wet technology for particle separation. It allows the separation of two-polymer mixtures into two products, one collected within the instrument and the other one expelled through its outlet ducts. Apparatus performance were analyzed as a function of fluid and solid flow rates, flow patterns developing within the apparatus, in addition to the density, shape, and size of the polymers. For the hydraulic configurations tested, a two-way coupling takes place where the fluid exerts an influence on the plastic particles and the opposite occurs too. The interaction between the solid and liquid phases determines whether a certain polymer settles within the device or is expelled from the apparatus. Tests carried out with samples of increasing volumes of solid particles demonstrate that there are no significant differences in the apparatus effectiveness as far as a two-way interaction takes place. Almost pure concentrates of Polyethylene Terephthalate (PET), Polyvinyl Chloride (PVC), and Polycarbonate (PC) can be obtained from a mixture of traditional polymers. Tests conducted on Polylactic Acid (PLA) and Mater-Bi® samples showed that the hydraulic separator can be effectively employed to separate bio-plastics from conventional plastics with remarkable grade and recovery.

Mechanical and healing properties of asphalt mixes reinforced with different types of waste and commercial metal particles

Improper disposal of metal waste in landfills is one of the primary means by which metals, mainly produced in different industrial sectors, reach the soil and ground water. These can migrate to surrounding ecosystems and bio-magnify in plants and animals endangering human food chain. At the same time, the addition of metal particles in asphalt mixes produces a series of beneficial effects, such as enhancing their mechanical performance, durability and electrical conductivity making possible applications, such as ice/snow melting and cracks healing by electromagnetic induction. The present investigation assesses and compares the use of two different types of waste metal fibres (recovered from old tyres and shavings from machining industry) and two other types of commercial particles (steel wool and steel grit) regarding their effect on volumetric, mechanical and healing properties of asphalt mixes. Results showed that, with a proper design, the improvement in such properties by using waste metals is comparable to that obtained by using commercial particles. It was also found that fibres from old tyres are especially suitable for low structural layers (base and sub-base), while the use of metal shavings is particularly recommendable in superficial course layers.

Greenhouse Gas Emission During Composting and Vermicomposting of Organic Wastes – A Review

Human‐induced climate change, mainly through greenhouse gases emission (GGE), is attracting attention worldwide and has become one of the major threats to the environmental sustainability. Utmost is the need to understand the impact of waste management practices on GGE, or countries could incorporate alternative waste management strategies for various organic wastes. Strict regulatory controls limiting waste disposal in landfills and the consequent diversion of biodegradables have resulted in the adoption of sustainable waste management techniques like composting and vermicomposting. However, composting and vermicomposting systems for waste management, especially at large scale have the capacity to emit high levels of greenhouse gases (GHGs). This paper reviews the current available literature pertaining to GGE during composting and vermicomposting of various organic wastes, linking with the fate of carbon (C) and nitrogen (N) during stabilization. Further, the current study provides a comprehensive summary of the emissions and plausible mechanisms and factors responsible for the GGE during both processes. The article also highlights likely mitigation actions relating to process parameters effective in minimizing GGE during composting and vermicomposting of organic wastes.

Application of ferric-silicon coagulant-flocculant of electric steel smelting slag for leachate treatment of communal solid waste landfills

In the Russian Federation the most common way of disposal of waste products is landfill. One of its drawbacks is the formation of highly contaminated filtration water. It was made an attempt to treat the leachate with a ferric coagulant-flocculant obtained from the electric steel smelting slag after the acid treatment with hydrochloric acid (the modification time of 1.5 N HCl at 40 °C is no more than 1 hour). To improve the treatment efficiency of highly contaminated leachate it was analysed a simultaneous application of the obtained coagulant-flocculant and conventional coagulants Al(SO4)2 and ferric chloride). It was shown a decrease in the values of the chemical oxygen demand (COD) by 94.4%, the color of the leachate by (91.3%). It was studied the physical and chemical properties of the filtration waters of the waste disposal landfill, as well as the dependence of the formation of the precipitable sediment volume on the portion of the injected coagulants and flocculant.

Current municipal solid waste management in the cities of Astana and Almaty of Kazakhstan and evaluation of alternative management scenarios

The present paper provides a detailed analysis of the current situation on municipal solid waste (MSW) management in Kazakhstan with focus on the two major cities, Astana and Almaty, the current and former capital of the country. Untill recently, ninety-seven percent of the MSW was disposed in open dumps and substandard authorized landfills. Ninety-three percent of the 4530 municipal waste disposal landfills were not permitted, while from the 307 authorized waste disposal facilities, only the one in the city of Astana was designed in accordance with international standards (2015). Core legislation, current management policy, existing and planned facilities and infrastructure, as well as solid waste quantity and composition are discussed. The analysis is complemented by the implementation of a decision support software tool, which provides insights in waste management needs and evaluates the alternative waste management plans. Six alternative scenarios were evaluated, and the results obtained demonstrate that the optimum scenario is separation at source for both biowaste, which is composted and packaging waste processed via the materials recovery facility. Regarding the residual waste, the optimum scenario for Astana is mechanical biological treatment (MBT)-composting-recyclables and waste-to-energy for the refuse-derived fuel (RDF). For Almaty, 80% of the waste should be processed through MBT-composting-recyclables, and 20% via incineration and RDF. The results obtained can contribute to solid waste management planning in Kazakhstan and other Central Asian countries.