Showing papers on "Waste disposal published in 2016"
TL;DR: In this article, the pyrolysis process for each type of plastics and the main process parameters that influenced the final end product such as oil, gaseous and char were reviewed.
1,150 citations
TL;DR: New studies indicate that, in addition to its cell-autonomous anti-tumorigenic functions, autophagy inhibits cancer development by orchestrating inflammation and immunity and should improve the efficacy of cancer immunotherapy.
455 citations
TL;DR: In this article, a wide variety of methods used to evaluate soil contamination are presented. But, it is very important to distinguish between the natural background values and anthropogenic inputs, and to understand that the background values change from area to area and with the scale of the area investigated.
Abstract: Heavy metals are natural constituents of soils and their concentration varies depending on parental materials. In the last years, the content of heavy metal in soils has increased due to human activities as: distribution of fertilizers, pesticides, industries, waste disposal and air pollution. Due to these activities the life capacity of soils decreased; especially where the natural background is already high because of natural parental material richness in heavy metal. As a matter of fact it is very important to distinguish between the natural background values and anthropogenic inputs, and to understand that the background values change from area to area and with the scale of the area investigated. There is currently a wide variety of methods used to evaluate soil contamination. To evaluate the soil contamination rate different indexes like Enrichment Factor (EF) and geoaccumulation index (Igeo) can be applied. These indexes are used to assess the presence and intensity of anthropogenic contaminant deposition on surface soil.
409 citations
TL;DR: This review highlights production and characteristics of carrageenan and alginate as sources of film-forming materials and indicates that water-soluble hydrocolloids like polysaccharides usually impart better mechanical properties to edible films and coatings than do hydrophobic substances.
405 citations
TL;DR: One of the causes of the increasing number of ecological distribution conflicts around the world is the changing metabolism of the economy in terms of growing flows of energy and materials as discussed by the authors, and there are conflicts on resource extraction, transport and waste disposal.
Abstract: One of the causes of the increasing number of ecological distribution conflicts around the world is the changing metabolism of the economy in terms of growing flows of energy and materials. There are conflicts on resource extraction, transport and waste disposal. Therefore, there are many local complaints, as shown in the Atlas of Environmental Justice (EJatlas) and other inventories. And not only complaints; there are also many successful examples of stopping projects and developing alternatives, testifying to the existence of a rural and urban global movement for environmental justice. Moreover, since the 1980s and 1990s, this movement has developed a set of concepts and campaign slogans to describe and intervene in such conflicts. They include environmental racism, popular epidemiology, the environmentalism of the poor and the indigenous, biopiracy, tree plantations are not forests, the ecological debt, climate justice, food sovereignty, land grabbing and water justice, among other concepts. These term...
330 citations
TL;DR: A balanced overview of the advantages and disadvantages of the pyrolysis process of biochar production, end-product quality and the benefits versus drawbacks ofBiochar on soil geochemistry and albedo, microflora and fauna and nutrients.
273 citations
TL;DR: The observations regarding the dissolved organic carbon, ammonium ions, and volatile suspended solids collectively indicated that the treatment by PMS more effectively disintegrated WAS compared to PDS, leading to higher weight (or volume) reduction by postcentrifugation.
Abstract: Oxidation by persulfates at elevated temperatures (thermally activated persulfates) disintegrates bacterial cells and extracellular polymeric substances (EPS) composing waste-activated sludge (WAS), facilitating the subsequent sludge dewatering. The WAS disintegration process by thermally activated persulfates exhibited different behaviors depending on the types of persulfates employed, that is, peroxymonosulfate (PMS) versus peroxydisulfate (PDS). The decomposition of PMS in WAS proceeded via a two-phase reaction, an instantaneous decomposition by the direct reaction with the WAS components followed by a gradual thermal decay. During the PMS treatment, the WAS filterability (measured by capillary suction time) increased in the initial stage but rapidly stagnated and even decreased as the reaction proceeded. In contrast, the decomposition of PDS exhibited pseudo first-order decay during the entire reaction, resulting in the greater and steadier increase in the WAS filterability compared to the case of PMS...
210 citations
TL;DR: Green analytical chemistry does not have a greenness metrics system as mentioned in this paper, and the analytical reagents were not assessed but some clues about their greenness can be obtained from assessments from other branches of chemistry.
Abstract: Green analytical chemistry, although not being a new concept, does not have a greenness metrics system. Green chemistry metrics are not suitable for analytical procedure assessment because they often refer to the mass of the product. Some efforts have been made to develop suitable metrics for analytical chemistry. Some are simple to use but do not cover all aspects of analytical methods’ environmental impact. Others are more comprehensive but may be difficult to be applied. The analytical reagents were not assessed but some clues about their greenness can be obtained from assessments from other branches of chemistry. New reagents and solvents applied in analytical chemistry require their detailed assessment in terms of greenness. Environmental issues have to be taken into consideration during reagent and solvent selection, analytical waste disposal practices, the energetic requirements of analytical processes and the development or selection of analytical procedures, and, for that reason, metrics systems are required.
210 citations
TL;DR: In this article, the authors investigated the possibility of using various types of waste powders, generated from marble and granite industry, as mineral additives in self-compacting concrete (SCC).
202 citations
TL;DR: In this paper, a mix design methodology for GPC with the main focus on achieving better compressive strength in an economical way for different alkaline solutions to binder proportions was proposed.
202 citations
TL;DR: These novel geopolymeric monoliths can be used in packed beds that are easily collected when exhausted, which is a major advantage in comparison with the use of powdered adsorbents, and their production encompasses the reuse of biomass fly-ash, mitigating the environmental impact associated with this waste disposal, while decreasing the adsorbent production costs.
TL;DR: In this review, fundamental understandings on the energy-generating capacity of MFC from real waste treatment are provided and the challenges and opportunities are discussed and the limiting factors restricting the energy output and impairing the long-term reliability are analyzed.
Abstract: Organic wastes are now increasingly viewed as a resource of energy that can be harvested by suitable biotechnologies. One promising technology is microbial fuel cells (MFC), which can generate electricity from the degradation of organic pollutants. While the environmental benefits of MFC in waste treatment have been recognized, their potential as an energy producer is not fully understood. Although progresses in material and engineering have greatly improved the power output from MFC, how to efficiently utilize the MFC's energy in real-world scenario remains a challenge. In this review, fundamental understandings on the energy-generating capacity of MFC from real waste treatment are provided and the challenges and opportunities are discussed. The limiting factors restricting the energy output and impairing the long-term reliability of MFC are also analyzed. Several energy storage and in situ utilization strategies for the management of MFC's energy are proposed, and future research needs for real-world application of this approach are explored.
TL;DR: The review suggested that some international fertilizer recommendations may underestimate mineralizable N in biosolids, and the N fertilizer value, and greater economic and environmental savings in mineral N fertilizer application are potentially possible than are currently realized from biosolid recycling programmes.
TL;DR: In this paper, a review on the utilization of emerging alternative farming waste materials in concrete such as from the farming of bamboo, corn, wheat, olive, sisal, seashells and more is carried out with the aim of examining the benefits and shortcomings of using these materials.
TL;DR: In this paper, the possibility of utilizing the bioorganic tomato peel as a cheap source for pectin production and its application as a corrosion inhibitor was investigated to implement viable cyclical economy principle in solving the main problem of waste disposal.
TL;DR: It is concluded that microneedle patches offer a powerful new technology that can enable more effective vaccination in developing countries.
TL;DR: An improved version of Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) applied to obtain the best municipal solid waste management method by comparing and ranking the scenarios and results show the mix of recycling and anaerobic digestion and a sanitary landfill with Electricity Production are the preferred options for MSW management.
TL;DR: Investigation of silver nanoparticles in a sludge-amended soil cultivated with monocot and dicot crop species shows that Ag was preferentially associated with S-rich particles, including organic fragments, of the sludge and amended soils, and Nano-XRF evidenced the presence of mixed metallic sulfides.
Abstract: The objective of this work was to investigate the fate of silver nanoparticles (Ag-NPs) in a sludge-amended soil cultivated with monocot (Wheat) and dicot (Rape) crop species. A pot experiment was performed with sludges produced in a pilot wastewater treatment plant containing realistic Ag concentrations (18 and 400 mg kg(-1), 14 mg kg(-1) for the control). Investigations focused on the highest dose treatment. X-ray absorption spectroscopy (XAS) showed that Ag2S was the main species in the sludge and amended soil before and after plant culture. The second most abundant species was an organic and/or amorphous Ag-S phase whose proportion slightly varied (from 24% to 36%) depending on the conditions. Micro and nano X-ray fluorescence (XRF) showed that Ag was preferentially associated with S-rich particles, including organic fragments, of the sludge and amended soils. Ag was distributed as heteroaggregates with soil components (size ranging from ≤0.5 to 1-3 μm) and as diffused zones likely corresponding to sorbed/complexed Ag species. Nano-XRF evidenced the presence of mixed metallic sulfides. Ag was weakly exchangeable and labile. However, micronutrient mobilization by plant roots and organic matter turnover may induce Ag species interconversion eventually leading to Ag release on longer time scales. Together, these data provide valuable information for risk assessment of sewage sludge application on agricultural soils.
TL;DR: In this article, the authors present a systematic literature review of heterogeneous TiO2 photocatalysis dealing with pre and post treatment of municipal solid waste (MSW) landfill leachate.
TL;DR: In this paper, the authors examined the strength and durability behavior of concrete containing granite cutting waste (GCW) to determine its viability in concrete production and showed that GCW can be used as a partial substitute of river sand and thereby reducing cost of concrete production.
TL;DR: In this paper, a review of the literature on the modeling of reverse logistics inventory systems that are based on the economic order/production quantity (EOQ/EPQ) and the joint economic lot size (JELS) settings is presented.
TL;DR: Varnish biodegradation analyses showed that fungi were able to break down the polymer in some of their precursors, offering the possibility that they may be recovered and used for new polyurethane synthesis.
Abstract: Polyurethane (PU) is widely used in many aspects of modern life because of its versatility and resistance. However, PU waste disposal generates large problems, since it is slowly degraded, there are limited recycling processes, and its destruction may generate toxic compounds. In this work, we isolated fungal strains able to grow in mineral medium with a polyester PU (PS-PU; Impranil DLN) or a polyether PU (PE-PU; Poly Lack) varnish as the only carbon source. Of the eight best Impranil-degrading strains, the six best degraders belonged to the Cladosporium cladosporioides complex, including the species C. pseudocladosporioides, C. tenuissimum, C. asperulatum, and C. montecillanum, and the two others were identified as Aspergillus fumigatus and Penicilliumchrysogenum. The best Impranil degrader, C. pseudocladosporioides strain T1.PL.1, degraded up to 87% after 14 days of incubation. Fourier transform infrared (FTIR) spectroscopy analysis of Impranil degradation by this strain showed a loss of carbonyl groups (1,729 cm −1 ) and N—H bonds (1,540 and 1,261 cm −1 ), and gas chromatography-mass spectrometry (GC-MS) analysis showed a decrease in ester compounds and increase in alcohols and hexane diisocyanate, indicating the hydrolysis of ester and urethane bonds. Extracellular esterase and low urease, but not protease activities were detected at 7 and 14 days of culture in Impranil. The best eight Impranil-degrading fungi were also able to degrade solid foams of the highly recalcitrant PE-PU type to different extents, with the highest levels generating up to 65% of dry-weight losses not previously reported. Scanning electron microscopy (SEM) analysis of fungus-treated foams showed melted and thinner cell wall structures than the non-fungus-treated ones, demonstrating fungal biodegradative action on PE-PU.
IMPORTANCE Polyurethane waste disposal has become a serious problem. In this work, fungal strains able to efficiently degrade different types of polyurethanes are reported, and their biodegradative activity was studied by different experimental approaches. Varnish biodegradation analyses showed that fungi were able to break down the polymer in some of their precursors, offering the possibility that they may be recovered and used for new polyurethane synthesis. Also, the levels of degradation of solid polyether polyurethane foams reported in this work have never been observed previously. Isolation of efficient polyurethane-degrading microorganisms and delving into the mechanisms they used to degrade the polymer provide the basis for the development of biotechnological processes for polyurethane biodegradation and recycling.
TL;DR: This paper presents the first Big Data based architecture for construction waste analytics, validated for exploratory analytics of 200,000 waste disposal records from 900 completed projects and revealed that existing waste management software classify the bulk of construction waste as mixed waste, which exposes poor waste data management.
Abstract: In recent times, construction industry is enduring pressure to take drastic steps to minimise waste. Waste intelligence advocates retrospective measures to manage waste after it is produced. Existing waste intelligence based waste management software are fundamentally limited and cannot facilitate stakeholders in controlling wasteful activities. Paradoxically, despite a great amount of effort, the waste being produced by the construction industry is escalating. This undesirable situation motivates a radical change from waste intelligence to waste analytics (in which waste is propose to be tackle proactively right at design through sophisticated big data technologies). This paper highlight that waste minimisation at design (a.k.a. designing-out waste) is data-driven and computationally intensive challenge. The aim of this paper is to propose a Big Data architecture for construction waste analytics. To this end, existing literature on big data technologies is reviewed to identify the critical components of the proposed Big Data based waste analytics architecture. At the crux, graph-based components are used: in particular, a graph database (Neo4J) is adopted to store highly voluminous and diverse datasets. To complement, Spark, a highly resilient graph processing system, is employed. Provision for extensions through Building Information Modelling (BIM) are also considered for synergy and greater adoption. This symbiotic integration of technologies enables a vibrant environment for design exploration and optimisation to tackle construction waste. The main contribution of this paper is that it presents, to the best of our knowledge, the first Big Data based architecture for construction waste analytics. The architecture is validated for exploratory analytics of 200,000 waste disposal records from 900 completed projects. It is revealed that existing waste management software classify the bulk of construction waste as mixed waste, which exposes poor waste data management. The findings of this paper will be of interest, more generally to researchers, who are seeking to develop big data based simulation tools in similar non-trivial applications.
TL;DR: In this paper, the acute toxicity of silver nanoparticles (AgNPs) using a freshwater fish Labeo rohita as an aquatic animal model was emphasized. And the results of this investigation showed that increasing the concentration of AgNPs led to bioaccumulation of AgNs in the major tissues.
Abstract: The increasing use of nano based-products induces the potential hazards from their manufacture, transportation, waste disposal and management processes. In this report, we emphasized the acute toxicity of silver nanoparticles (AgNPs) using freshwater fish Labeo rohita as an aquatic animal model. The AgNPs were synthesized using chemical reduction method and the formation of AgNPs was monitored by UV–Visible spectroscopy analysis. The functional groups, crystaline nature and morphological characterizations were carried out by fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) analysis. UV-Vis range was observed at 420 nm and XRD pattern showed that the particles are crystalline nature. HRTEM analysis revealed that the morphology of particles was spherical and size ranges between 50 and 100 nm. This investigation was extended to determine the potential acute toxicity, L. rohita was treated orally with the lethal concentration (LC50) of AgNPs. The antioxidative responses were studied in the three major tissues such as gill, liver and muscle of L. rohita. The results of this investigation showed that increasing the concentration of AgNPs led to bioaccumulation of AgNPs in the major tissues. The haematological parameters showed significant alterations in the treated fish. The histological changes caused by chemically synthesized AgNPs demonstrated the damages in the tissues, primary lamella and blood vessels of L. rohita. The histological study also displayed the formation of vacuolation in liver and muscle when compared with untreated tissues (control) of L. rohita.
TL;DR: To provide a more comprehensive understanding of the health risks of wastewater use in agriculture, future research should consider multiple exposure routes, long-term health implications, and increase the range of contaminants studied, particularly in regions heavily dependent on wastewater irrigation.
Abstract: Background:Wastewater is increasingly being used in the agricultural sector to cope with the depletion of freshwater resources as well as water stress linked to changing climate conditions. As wast...
TL;DR: In this paper, a hybrid method of interpretive structural modelling, fuzzy analytic hierarchy process, and fuzzy technique for order preference and similarity to ideal solution has been used to carry out this study.
TL;DR: In this article, the complexity of employing a larger surface area nanomaterial in the form of titania nanotubes has been investigated, and the degradation of pure and composite PE films was measured in terms of photo-induced weight loss and was confirmed by FTIR, SEM, surface roughness and tensile strength testing.
Abstract: Polyethylene (PE) waste disposal is a major issue now a days that poses serious threats to human and environmental health. Among the methods of dealing with problem, photocatalytic degradation in the visible light is an alternative option that has received attention recently. The photo catalyst, generally used, is titania in the nanoparticle form. In the current study, complexity of employing a larger surface area nanomaterial in the form of titania nanotubes has been investigated. Prepared nanostructures were characterized by SEM, EDS, XRD, BET surface area measurements and UV-visible spectroscopy. Taking a lead from the work done for the development of dye sensitized solar cells, blue green dye was used to sensitize the TNTs with very encouraging results. The degradation of pure and composite PE films was measured in terms of photo-induced weight loss and was confirmed by FTIR, SEM, surface roughness and tensile strength testing. Thus, polyethylene films with 10% dye sensitized titania nanotubes showed a degradation of around 50% under visible light over a short period of 45 days.
TL;DR: An awareness of proper waste management amongst health workers has been created in most hospitals through the initiative of LAWMA, however, hospital D still mixes municipal and hazardous wastes.
Abstract: Medical waste (MW) can be generated in hospitals, clinics and places where diagnosis and treatment are conducted. The management of these wastes is an issue of great concern and importance in view of potential public health risks associated with such wastes. The study assessed the medical waste management practices in selected hospitals and also determined the impact of Lagos Waste Management Authority (LAWMA) intervention programs. A descriptive cross-sectional survey method was used. Data were collected using three instrument (questionnaire, site visitation and in –depth interview). Two public (hospital A, B) and five private (hospital C, D, E, F and G) which provide services for low, middle and high income earners were used. Data analysis was done with SPSS version 20. Chi-squared test was used to determine level of significance at p < 0.05. The majority 56 (53.3 %) of the respondents were females with mean age of 35.46 (±1.66) years. The hospital surveyed, except hospital D, disposes both general and medical waste separately. All the facilities have the same process of managing their waste which is segregation, collection/on-site transportation, on-site storage and off–site transportation. Staff responsible for collecting medical waste uses mainly hand gloves as personal protective equipment. The intervention programs helped to ensure compliance and safety of the processes; all the hospitals employ the services of LAWMA for final waste disposal and treatment. Only hospital B offered on-site treatment of its waste (sharps only) with an incinerator while LAWMA uses hydroclave to treat its wastes. There are no policies or guidelines in all investigated hospitals for managing waste. An awareness of proper waste management amongst health workers has been created in most hospitals through the initiative of LAWMA. However, hospital D still mixes municipal and hazardous wastes. The treatment of waste is generally done by LAWMA using hydroclave, to prevent environmental hazards except hospital B that treats its sharp with an incinerator. In order to enhance uniform and appropriate waste management practices in the entire State, there is need for capacity building at all levels and also policies and guidelines formulations.
TL;DR: Results from this study revealed the mechanisms of P transformation during (hydro)thermal treatments of sewage sludges, and might be applicable to other biosolids, and provided fundamental knowledge basis for the design and selection of waste management strategies for better P (re)cycling and reclamation.
TL;DR: An overview of the different techniques that so far have been applied for conversion of date stone to carbon adsorbent is provided in this article, where the effects of temperature, time, impregnation ratio, and type of activator on pore characteristics and yield of carbons were reviewed.