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1.
J Environ Manage ; 270: 110910, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721344

RESUMO

Flux agents play an important role in the pyrolysis treatment of vitrifying hazardous wastes. Among these is plasma jets, a cost-less flux agent derived from shell powder which can be used to create vitrification. It is a promising option to be applied in the vitrification of elements and to remove the VOCs of hazardous waste, namely, resin from PCB scrap in an atmospheric-pressure microwave plasma reactor. In this study, a laboratory scale experiment was conducted. The experiment was performed in the pyrolysis of resin which was added with flux agents. The economic evaluation of the flux agents, and the circular economy concept of the final residue derived from the plasma pyrolysis was then analyzed post treatment. To test the strength and weakness of the experiment, the SWOT analysis was performed. The outcome helped in the understanding of the cost-less flux agent used in the pyrolysis treatment of hazardous waste. Results showed that fusing shell powder in resin was better for improving the removal efficiency of VOCs, such as benzene and toluene as well as toxic metals than compared to other flux agents such as limestone and quartz sand. Moreover, the final residue of resin was found to fulfil the concept of circular economy where it could be reused as an absorbent of methyl blue, thereby indicating good absorption performance, from 1 ppm-100 ppm. The twelve strategies that were derived from the SWOT analysis could be used as information outlining the current internal and external condition for the development and application of shell powder. Shell powder, as a cost-less flux agent, has the potential for enhancing waste management and circular economy when used in the pyrolysis treatment of future hazardous wastes.


Assuntos
Vitrificação , Gerenciamento de Resíduos , Resíduos Perigosos , Pirólise , Tolueno
3.
Chemosphere ; 250: 126290, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32120149

RESUMO

Arsenic- and trace metals-bearing gypsum (As-gypsum) is one of the major hazardous solid wastes produced from metallurgical industry that poses a serious threat to the environment. However, the method for effective extraction of As and trace metals from As-gypsum is still lacking. In this study, simultaneous extraction of As and trace metals from a hydrometallurgical As-gypsum via hydrothermal recrystallization in acid solution was investigated. The effects of the type (H2SO4 vs HCl) and concentration of acid, and temperature on extraction efficiency were assessed. The results showed that 99% As, >92% Cu and >96% Zn could be extracted from the As-gypsum during hydrothermal treatment in 6 mol L-1 H2SO4 at 90 and 120 °C, but Pb and Cd could not be extracted efficiently. The results of hydrothermal treatment in HCl solutions demonstrated that higher HCl concentration and temperature significantly enhanced the extraction efficiency and 100% As, Cu2+, Zn2+, Pb2+ and >90% Cd were removed from the As-gypsum after treatment in 6 mol L-1 HCl, at 120 °C, for 12 h. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy results revealed that dissolution-recrystallization of gypsum is the key process for the removal of the incorporated As and trace metals. Thermodynamic modelling indicated that the released HAsO42-/Me2+ transformed into H3AsO4/MeCln(2-n) (1 ≤ n ≤ 4) species in HCl solution, hence inhibiting their reincorporation into the recrystallization products via isomorphic substitution for SO42-/Ca2+. This work provides a simple and effective method for detoxification and reclamation of As-gypsum.


Assuntos
Arsênico/química , Arsênico/toxicidade , Sulfato de Cálcio/química , Resíduos Perigosos , Inativação Metabólica , Metalurgia , Metais , Metais Pesados/química , Oligoelementos/química , Difração de Raios X
4.
Chemosphere ; 250: 126269, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32126330

RESUMO

MSWI(Municipal solid waste incineration) fly ash as hazardous wastes usually is treated properly with OPC(ordinary Portland cement) based binders prior to being disposed in security landfill, but some toxic elements present poor stability in its highly alkaline environment. This study developed a novel solidification/stabilization technology based on MgO-SiO2-H2O (M-S-H) cementious material with compatibility with contaminants for MSWI fly ash encapsulation. Compressive strength and leaching toxicity tests were undertaken to evaluate the immobilization effect of MSWI fly ash treated with M-S-H matrix. And TAM, XRD, DTA/TGA and SEM techniques were employed to explore hydration process and microstructure morphology of M-S-H solidified body. Results demonstrated that M-S-H cement matrix played a positive impact on the immobilization of heavy metals, and the immobilization rate of Cd, Pb and Zn was 97.5%, 99.8% and 98.7%, which was far more than that fixed in Portland cement. The incorporation of MSWI fly ash inhibited the hydration process of M-S-H matrix on the whole, which was mainly due to its poor pozzolanic activity. Moreover, there were some new hydration phases including CdSiO3, Ca3PbSiO6 and Zn(OH)2 generated and some MSWI fly ash embedded in the core-shell structure of M-S-H matrix in depth. These results suggested that heavy metals of MSWI fly ash were mainly fixed in M-S-H solidified bodies by physical encapsulation, isomorphous replacement and chemical precipitation. Overall, this study demonstrated that M-S-H matrix is a promising candidate that can serve as low-carbon and high-efficient materials for hazardous MSWI fly ash.


Assuntos
Incineração , Carbono/química , Força Compressiva , Materiais de Construção , Resíduos Perigosos , Óxido de Magnésio/química , Metais Pesados/análise , Material Particulado/química , Eliminação de Resíduos/métodos , Dióxido de Silício/química , Resíduos Sólidos/análise
5.
Environ Sci Pollut Res Int ; 27(12): 14198-14206, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32037492

RESUMO

Chlorotoluene rectification residual liquid (CRRL) from chlorotolune industry is hard to dispose of because of its high chlorine concentration, which poses high dioxin risk once it is subjected to incinerate. This research employed a chemical approach by using Williamson ether synthesis (WES) method for CRRL dechlorination. It shows that the sodium dosage, the ethanol dosage, and the ultrasonic time are the key factors in chlorine removal. The highest removal rate of chlorine was observed when the sodium dosage, the ethanol dosage, and the ultrasonic time were 0.35 g mL-1, 0.8 mL mL-1, and 15 min, respectively. The further optimization tests indicate that the highest chlorine removal efficiency of 39.06% was observed when the ultrasonic time was 15 min, the sodium dosage and the ethanol dosage were 0.5 g mL-1 and 1.1 mL mL-1, respectively. It suggests a feasible chlorine removal process for organic hazardous waste with high chlorine content before incineration.


Assuntos
Cloro , Dioxinas , Éteres , Resíduos Perigosos , Incineração
6.
J Environ Sci (China) ; 90: 364-374, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32081332

RESUMO

The leaching concentrations of different metals in stainless steel pickling residue (SSPR) were determined and the toxic metals were treated using Na2S∙xH2O, FeSO4∙6H2O, and phosphoric acid. A modified European Community Bureau of Reference (BCR) sequential extraction was used to identify the speciation of the concerned metals. Results showed that SSPR contains a large amount of Ca (58.41%), Fe (29.44%), Cr (3.83%), Ni (2.94%), Mn (2.82%) and some of Al, Cu, Mg, Zn. Among them, Cr and Ni were the most toxic metals in SSPR, thus the raw SSPR falls into hazardous waste category due to the leaching amount of Cr. In addition, the leached Cr was identified as Cr6+ (MgCrO4) in the waste. BCR test revealed that risk assessment code (RAC) of Cr and Ni were 33.29% and 61.7%, indicating they posed "high" and "very high" risk to the environment, respectively. After fixing by Na2S∙xH2O and FeSO4∙6H2O, the leaching concentrations of Cr and Ni were less than 1.5 and 0.5 mg/L, respectively. After fixing by Na2S∙xH2O and FeSO4∙6H2O the treated SSPR can be safely reused as roadbed materials, concrete and cement aggregates. This study provides a useful implication in treatment and beneficial reuse of heavy metal-containing hazardous wastes.


Assuntos
Resíduos Perigosos/análise , Metais Pesados , Aço Inoxidável , Ácidos Fosfóricos/química
7.
Chemosphere ; 249: 126204, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32088457

RESUMO

Spent potlining (SPL) as a hazardous solid waste has a high content of inorganic fluorine. This study aimed at characterizing its transformation, retention and leaching behaviors with(out) the addition of red mud (RM) during the SPL incineration. The RM addition positively affected its retention and leaching rates. Its Ca-containing compounds caused Na3AlF6 and NaF to turn into more CaF2. 30% RM converted water-soluble NaF into more stable CaF2 than did SPL at 850 °C, thus reducing the leaching rate by 45.15%. 30% RM captured HF through its Ca content and enhanced its retention rate by 66.96%. 66.01% of the total fluorine was stably retained in the bottom ash, and thus, significantly reduced the toxicity of the SPL incineration products. SiO2 and Al2O3 exerted a thermally positive effect on NaF turning into CaF2. The fluoride retention of the bottom ash was mainly dominated by CaF2 and NaF with(out) RM. Smaller, coarser and more loose structures of the co-incinerated solid particles pointed to a synergistic interaction between SPL and RM.


Assuntos
Flúor/química , Incineração , Modelos Químicos , Cinza de Carvão/química , Fluoretos , Resíduos Perigosos , Dióxido de Silício , Resíduos Sólidos , Termodinâmica , Água
8.
Waste Manag Res ; 38(3): 312-321, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31918651

RESUMO

The recycling of polyvinyl chloride (PVC) recovered from the plastic insulations in wires and cables is a rising concern in the current situation due to its hazardous behaviour during recycling. Similarly, high-impact polystyrene (HIPS) and acrylonitrile butadiene styrene (ABS) used in the structural components of electrical and electronic equipment are also generated in large quantities. In the current work, three agendas were fixed: (a) to determine the effect of recycled polymeric material (HIPS and ABS) recovered from different sources on the mechanical property of the polymeric blends; (b) to formulate a high-impact strength blend; and (c) to deduce a mechanism for improved impact strength. The mechanical characterizations were conducted on the entire blends formulated. Among them, the recycled blend composed of recycled PVC (r-PVC) and recycled ABS (r-ABS) (segregated from uninterrupted power supply housing) and recycled HIPS (r-HIPS; collected from television housing) was confined for further physio-mechanical and thermal analysis. Besides, the r-PVC/r-ABS systems had shown better mechanical properties than r-PVC/r-HIPS systems in similar composition. The impact strength of blend r-PVC/r-ABS (70:30) was found to be 250 J/m, which was 200% more than the blend r-PVC/r-ABS (0:100). The compatibility and non-compatibility in PVC/ABS and PVC/HIPS blends respectively were explained with thermal, mechanical and morphological characterizations. Furthermore, a plausible cross-linking mechanism is developed between ABS and PVC, which controls the release of chlorine atoms into the environment.


Assuntos
Acrilonitrila , Resíduo Eletrônico , Resíduos Perigosos , Plásticos , Reciclagem
9.
Sci Total Environ ; 710: 136313, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31923676

RESUMO

Hazardous waste landfills (HWLs) usually mean the end of non-reusable, non-recyclable and non-recoverable wastes derived from industrial activities. A number of hazardous compounds and toxic elements, such as PCDD/Fs, Cd, Cr, Hg, Pb and As, is associated to these wastes. The HWL of Castellolí (Catalonia, Spain) treats a variety of hazardous wastes, which include bottom ashes from waste incinerators and asbestos potentially containing those toxicants. In 2007, our group began a surveillance program inside the HWL and in nearby villages focused on assessing the environmental levels of PCDD/Fs and toxic elements. Here we summarize the most updated results, corresponding to data from samples collected between 2015 and 2018. The levels of most trace elements (As, Cd, Cr, Ni and Pb) in soils, as well as those of Cd and Pb in air, were significantly higher (p < 0.01) inside the HWL than outside. However, no relevant differences were noted in the concentrations of trace elements when comparing the results of villages near the HWL with those located farther. With respect to PCDD/Fs, a progressive decrease was observed between the first (2007) and most recent (2018) surveys. The human health risks associated with the exposure to trace elements and PCDD/Fs exposure were within acceptable ranges according to national and international legislations (HQ < 1 and Cancer risk < 10-5).


Assuntos
Resíduos Perigosos/análise , Dibenzofuranos , Dibenzofuranos Policlorados , Monitoramento Ambiental , Humanos , Incineração , Dibenzodioxinas Policloradas , Espanha , Oligoelementos , Instalações de Eliminação de Resíduos
10.
Environ Sci Pollut Res Int ; 27(1): 89-100, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30972676

RESUMO

Among the actions proposed by the European Union for the implementation of Circular Economy is the use of waste as a secondary raw material (SRM). During the fusion of the scrap, a steel dust is generated, named electric arc furnace dust (EAFD). The EAFD is composed mainly of potentially leachable heavy metals and is classified as a "hazardous" waste. Worldwide, approximately 70% of EAFD is deposited in landfills, with a previous treatment through cement-based materials to prevent the metals' mobility. However, this action is not in accordance with the Circular Economy concept. The present investigation analyses the use of EAFD as SRM in conventional mortar production for its use as a construction material. Different substitution percentages (25, 50 and 100%) were used replacing the siliceous filler by EAFD. A preceding characterisation of the waste by X-ray fluorescence, X-ray diffraction, specific surface area, bulk density, electron microscopy and particle size distribution was performed. The investigation analysed the behaviour of conventional mortars by tests of workability, compressive strength, mineralogy, water absorption by capillarity, and leaching behaviour in granular and monolithic states. The results obtained indicate a slight improvement in mechanical behaviour with the incorporation of EAFD, the reason why its use as SRM in conventional mortars would benefit the construction industry and would encourage the Circular Economy. From an environmental point of view, the mechanisms of Pb fixation should be improved in a granular state.


Assuntos
Materiais de Construção , Poeira/análise , Força Compressiva , Eletricidade , Resíduos Perigosos , Metais Pesados/análise , Aço , Difração de Raios X
11.
Chemosphere ; 241: 124964, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31604195

RESUMO

Around former glass factories in south eastern Sweden, there are dozens of dumps whose radioactivity and physico-chemical properties were not investigated previously. Thus, radiometric and physico-chemical characteristics of waste at Madesjö glass dump were studied to evaluate pre-recycling storage requirements and potential radiological and environmental risks. The material was sieved, hand-sorted, leached and scanned with X-Ray Fluorescence (XRF). External dose rates and activity concentrations of Naturally Occurring Radioactive Materials from 238U, 232Th series and 40K were also measured coupled with a radiological risk assessment. Results showed that the waste was 95% glass and dominated by fine fractions (<11.3 mm) at 43.6%. The fine fraction had pH 7.8, 2.6% moisture content, 123 mg kg-1 Total Dissolved Solids, 37.2 mg kg-1 Dissolved Organic Carbon and 10.5 mg kg-1 fluorides. Compared with Swedish EPA guidelines, the elements As, Cd, Pb and Zn were in hazardous concentrations while Pb leached more than the limits for inert and non-hazardous wastes. With 40K activity concentration up to 3000 Bq kg-1, enhanced external dose rates of 40K were established (0.20 µSv h-1) although no radiological risk was found since both External Hazard Index (Hex) and Gamma Index (Iγ) were <1. The glass dump needs remediation and storage of the waste materials under a safe hazardous waste class 'Bank Account' storage cell as a secondary resource for potential future recycling.


Assuntos
Fenômenos Químicos , Vidro/análise , Poluentes Radioativos/análise , Resíduos Radioativos/análise , Resíduos/análise , Resíduos Perigosos , Radioisótopos de Potássio/análise , Reciclagem , Espectrometria por Raios X , Suécia , Tório/análise , Urânio/análise
12.
Environ Sci Pollut Res Int ; 27(4): 4227-4235, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31828702

RESUMO

Hazardous waste landfill leachate (HWLL) with high concentrations of salt and pollutants has created a bottleneck at hazardous waste landfills. This study applied a cement-based curing method to the disposal of HWLL. The highest contaminant fixing rate was achieved by adjusting the composition and proportion of the curing base, the content of additives, and the liquid-solid (L/S) ratio of the leachate to the curing base. The fixing rates for chemical oxygen demand and salt content in HWLL reached the highest values of 95.1% and 86.1%, respectively, when the Portland cement to metakaolin ratio was 3:2; the L/S was 1; and diatomite and activated carbon were added at 0.5% and 0.25%, respectively. The addition of glass fiber to the curing base improved the crack resistance of the solidified product. A simulated landfill experiment further indicated that after 116 days of leaching, the leachate effluent pollutant concentrations of the landfill column were lower than the effluent standard. Solidification is a feasible method for HWLL disposal.


Assuntos
Resíduos Perigosos , Eliminação de Resíduos/métodos , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água , Análise da Demanda Biológica de Oxigênio , Resíduos Sólidos
13.
Waste Manag Res ; 38(1): 44-58, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31438782

RESUMO

The main objective of this research was to investigate the waste characteristics and management activities in the Savojbolagh industrial zone, Iran, in order to rank the active industries from environmental perspectives using an innovative index. First, the industrial categories with over 50 employees were identified and classified according to their production process. Then, 54 industries were selected and all industrial processes, the types and quantities of products, per capita industrial waste generation, physical analysis and management activities in terms of minimisation, storage, processing, recycling and disposal were evaluated. The required data were obtained through questioners, interviews and field observations. A scoring system was prepared for evaluation of environmental status of waste management practices. Results indicated that the total industrial waste generation rate was 67,258 kg d-1, in which 4528 belonged to hazardous waste. Furthermore, the per capita waste generation rate was 5.51 kg d-1. Plastic, paper and cardboard and metals constituted the most fractions of wastes, respectively. Food and beverage, metallic and chemical/plastic industries were the biggest waste generators. Metallic industries with total score of 502.5 and non-metalic-mineral industries with the total score of 114 were categorised as the best and worst industries in terms of waste management practices.


Assuntos
Resíduos Industriais , Gerenciamento de Resíduos , Resíduos Perigosos , Irã (Geográfico) , Reciclagem
14.
Waste Manag Res ; 38(4): 433-443, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31739769

RESUMO

Estimation of construction waste generation is critical to construction waste management decisions. However, current construction waste estimation methods have various limitations (e.g. small samples). To address those limitations, this research conducts an empirical study to evaluate the waste generation rate of different types of waste at different construction stages. In this study, construction waste from 148 new-built residential construction sites in China were sorted and weighted on site and their waste generation rates were estimated separately. The results indicated that the amount of inorganic nonmetallic waste with a generation rate of 16.59 kg m-2 was the highest among the five types of waste (i.e. inorganic nonmetallic waste, organic waste, metallic waste, composite waste, hazardous waste), while the waste generation rate for the underground construction stage, which was 27.57 kg m-2, was the highest among the three stages (i.e. underground stage, superstructure stage, finishing stage). Compared with previous data, the new waste generation rate proposed in this research can better estimate the actual waste generation situation in construction sites, which provides reliable information for proper decision-making. Furthermore, based on the result of the empirical study, some recommendations for construction waste reduction are proposed.


Assuntos
Materiais de Construção , Gerenciamento de Resíduos , China , Tomada de Decisões , Resíduos Perigosos
15.
Chemosphere ; 243: 125351, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31756654

RESUMO

Hazardous waste disposal is a serious environmental concern in China. Therefore, in this study, industrial trials were conducted in a low-temperature thermal degradation facility, a tunnel kiln, and a shaft kiln to effectively treat dioxins in municipal solid waste incineration (MSWI) fly ash. The results indicated that the low-temperature thermal degradation facility efficiently decomposed polychlorinated dibenzo-p-dioxins and dibenzofurans in the MSWI fly ash. Additionally, the concentrations of dioxins in the treated fly ash and exhaust gas were lower than the suggested standard limits and the degradation ratio of dioxins was ∼99%. Therefore, treated fly ash characterized by acceptable dioxin risks could be utilized for the production of non-fired building materials. The results from the tunnel kiln indicated complete decomposition of the dioxins in the firing and insulating sections. However, the addition of fly ash in the tunnel kiln increased the concentration of dioxins in the flue gas. This can be primarily attributed to the heterogeneous catalytic synthesis reaction in the low-temperature section of the tunnel kiln. The results from the shaft kiln indicated degradation of at least 22% of the dioxins in the ash. The dioxin concentration in the flue gas was lower than the national standard while that in the clinker was within a reasonable limit. Furthermore, the environmental risks were significantly reduced at fly ash addition ratios lower than 3%.


Assuntos
Dibenzofuranos Policlorados/química , Resíduos Perigosos/análise , Incineração/métodos , Dibenzodioxinas Policloradas/química , China , Cinza de Carvão , Materiais de Construção , Dibenzofuranos , Dioxinas , Indústrias , Dibenzodioxinas Policloradas/análise , Eliminação de Resíduos , Resíduos Sólidos
16.
Environ Geochem Health ; 42(1): 77-94, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31011940

RESUMO

The assessment of heavy metal contents in environmental sectors is important to estimate the carcinogenic and non-carcinogenic doses and risks for the mankind associated with it. The present work deals with the assessment of the risk exposure related to heavy metal contents in groundwater and soil samples to two different age groups via three different transits, i.e., ingestion, inhalation and dermal. The concentrations of heavy metals (Zn, Cd, Cu, Pb and Cr) were measured in the villages of lower Himalayas of Reasi district by using microwave plasma atomic emission spectrometer. The calculated mean contamination factors of heavy metals in soil samples were as: Zn, 0.73; Cu, 0.70; Pb, 0.74; and Cr, 0.33; which led to pollution load index less than unity. The overall carcinogenic risks have been varied from 6.4E-08 to 5.1E-07 in soil samples and from 7.3E-06 to 1.1E-04 in ground water samples and were found to be well within the range prescribed by USEPA (Screening level ecological risk assessment protocol for hazardous waste combustion facilities, appendix E: toxicity reference values, US Environmental Protection Agency, Washington, D.C., 1999). The mean values of heavy metal contents except lead and chromium in water samples were found to be less than the values prescribed by various agencies. Geo-accumulation Index showed that Pb contribute to the highest contamination (0 < Igeo < 1) among the other heavy metals. Cluster analysis and principal component analysis identified that Zn, Cu, Pb and Cr had a relationship and the presence of these heavy metals could be related to vehicle emissions, traffic sources and industrial sources. The overall mean values of the non-carcinogenic doses and associated hazard risks in soil and water samples calculated for children were found to be higher than the adults which may be due to hand to mouth activities.


Assuntos
Exposição Ambiental/análise , Água Subterrânea/análise , Metais Pesados/toxicidade , Poluentes do Solo/toxicidade , Poluentes Químicos da Água/toxicidade , Adulto , Carcinógenos/análise , Carcinógenos/toxicidade , Criança , Exposição Ambiental/efeitos adversos , Resíduos Perigosos/análise , Humanos , Índia , Indústrias , Metais Pesados/análise , Medição de Risco , Poluentes do Solo/análise , Emissões de Veículos/análise , Emissões de Veículos/toxicidade , Poluentes Químicos da Água/análise
17.
Waste Manag ; 101: 188-199, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31622864

RESUMO

The scope of this paper is to identify the benefits of lamp recycling from the domestic sector. Data related to the recycled lamps was obtained from two recycling companies and were compared to those related to the waste lamps from the domestic sector. This was achieved by a new methodology which uses two alternative approaches. The first one is dependent on previous research data in relation to the number of active lamps while the second one elaborates on electricity consumption and sales data, in order to define the corresponding number of active lamps., The wasted amount of glass, metal and plastic is calculated along with the energy savings, the annual emissions of CO2-eq, the economic benefit from their sale and the potential reduction of hazardous waste, such as mercury to solid waste landfills under various scenarios. The amount of recovered materials collected by the Hellenic recycling companies contributes to a reduction of CO2-eq by 1298 tonnes, which falls significantly short of the CO2-eq that could have been saved 3108-5463tonnes if all the lamps were recycled. Furthermore, the recycling companies have an annual economic benefit of €32,251 which could be increased by €122,725 if all lamps were recycled together with the proper recycling of 3.4 kg of mercury, which was disposed in the environment. Finally, a future scenario was examined, in which all lamps in the domestic sector were assumed to be LEDs, an issue that can affect the viability of the recycling factories and it was proved that these might be affected.


Assuntos
Utensílios Domésticos , Mercúrio , Gerenciamento de Resíduos , Resíduos Perigosos , Iluminação , Reciclagem
18.
Chemosphere ; 240: 124885, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31568939

RESUMO

Chromium (Cr)-bearing electroplating sludge is a hazardous solid waste and has a detrimental effect on human health and the environment. In this study, an alkali-activated slag binders, namely, formed by the reaction of blast furnace slag (BFS) with alkali, was applied to the stabilization/solidification (S/S) of electroplating sludge. The effects of liquid-solid ratio, water glass modulus ratio (molar ratio of SiO2 to Na2O), water glass dosage, and electroplating sludge amount on the compressive strength and Cr leachability of binders were analyzed. The related mechanism of the S/S of electroplating sludge was discussed on the basis of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy coupled with energy-dispersive spectrometry (SEM-EDS). Results showed that the compressive strength of the alkali-activated slag binder first increased and then remained stable with the increase in liquid-solid ratio, water glass modulus ratio, and water glass dosage. By contrast, the leaching concentrations of Cr(VI) and total Cr decreased with the increase in liquid-solid ratio, water glass modulus ratio, water glass dosage, and curing time. In addition, XRD, FTIR, and SEM-EDS revealed that the hydration products of the binders were mainly low-crystallinity and dense calcium silicate hydrate gels, and Cr(VI) had been effectively immobilized in the structure. The reduction in Cr(VI) by the reductive components in the BFS boosted the stabilization of Cr-bearing electroplating sludge. Overall, the BFS binders containing electroplating sludge had relatively high compressive strengths and low Cr(VI) leaching concentrations. The physical encapsulation, chemical bonding, and absorption contributed the Cr immobilization during the S/S process of electroplating sludge.


Assuntos
Álcalis/química , Cromo/química , Galvanoplastia , Recuperação e Remediação Ambiental , Resíduos Perigosos/análise , Esgotos/química , Humanos
19.
Environ Monit Assess ; 192(1): 10, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31807921

RESUMO

Medical wastes are considered hazardous because they may possess infectious agents and can cause unsafe effects on the environment and human health. This study is to analyze and evaluate the current status of medical waste management at Jenin's district in light of medical waste control regulations recommended by the World Health Organization. The results demonstrated that the average hazardous healthcare waste generation rate ranges from 0.54 to 1.82 kg/bed/day with a weighted average of 0.78 kg/bed/day. There was no established waste segregation of healthcare waste types in all hospitals, and these wastes were finally disposed of in a centralized municipal sanitary landfill, namely Zahrat Al-Finjan. The results suggest that there is a need for activation and enforcement of medical waste laws. This can be achieved through cooperation among key actors: Ministry of Health, Environmental Quality Authority, Ministry of Local Government, and Non-Governmental Organizations working in related fields. Additional remediation measures proposed to tackle the problematic areas of medical waste management in Jenin's district hospitals are addressed. Some recommendations to minimize potential health and environmental risks of medical waste are also introduced.


Assuntos
Hospitais , Eliminação de Resíduos de Serviços de Saúde/métodos , Resíduos de Serviços de Saúde , Gerenciamento de Resíduos/métodos , Monitoramento Ambiental , Resíduos Perigosos/legislação & jurisprudência , Resíduos de Serviços de Saúde/legislação & jurisprudência , Eliminação de Resíduos de Serviços de Saúde/legislação & jurisprudência , Gerenciamento de Resíduos/legislação & jurisprudência
20.
Environ Manage ; 64(6): 783-793, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31732774

RESUMO

Environmental Management Systems (EMS) based on international standard ISO 14001 are recognized as a tool to improve the environment and the sustainability of organizations. Green Chemistry (GC) seeks to reduce the use and generation of hazardous substances in chemical processes. This paper studies the relationship between EMS based on ISO 14001 and GC. We have analysed their similarities, difficulties, advantages, and synergies that can be developed with a joint implementation in general and in particular on university campuses. The results show that both disciplines have in common the philosophy of Continuous Improvement in the Processes (CIP) and that their joint application is possible, since each principle of GC are related to, at least, one clause of ISO 14001. It is shown that this joint application to different university areas can generate benefits, such as the reduction of hazardous waste and the promotion of green purchases, which favour the environmental improvement of universities. However, there are problems in their joint application related to the lack of specific knowledge and the difficulty of identifying products manufactured following the criteria of GC. Furthermore, a case study in the San Jorge University showing that both disciplines can be treated together is shown. Results were the following: seven GC initiatives (proposed by a small group of GC students) were submitted to the EMS office; only one was considered nonviable and two were implemented, achieving two main goals: Reduction of the environmental impact of laboratories and promotion of green purchasing in the laboratories of San Jorge University.


Assuntos
Resíduos Perigosos , Universidades , Comércio , Conservação dos Recursos Naturais , Humanos
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