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Utilization of reverse osmosis (RO) for reuse of MBR-treated wastewater in irrigation-preliminary tests and quality analysis of product water 全文
2018
Bunani, Samuel | Yörükoğlu, Eren | Sert, Gökhan | Kabay, Nalan | Yüksel, Ümran | Yüksel, Mithat | Egemen, Özdemir | Pek, TaylanÖzgür
Membrane bioreactor (MBR) effluent collected from a wastewater treatment plant installed at an industrial zone was used for reverse osmosis (RO) membrane tests in the laboratory. For this, two different GE Osmonics RO membranes (AK-BWRO and AD-SWRO) were employed. The results showed that AK-brackish water reverse osmosis (AK-BWRO) and AD-seawater reverse osmosis (AD-SWRO) membranes have almost similar rejection performances regarding analyzed parameters such as conductivity, salinity, color, chemical oxygen demand (COD), and total organic carbon (TOC). On the other hand, these membranes behaved quite differently considering their permeate water flux at the same applied pressure of 10 bar. AD-SWRO membrane was also tested at 20 bar. The results revealed that AD-SWRO membrane had almost the same rejections either at 10 or at 20 bar of applied pressure. Compared with irrigation water standards, AK-BWRO and AD-SWRO gave an effluent with low salinity value and sodium adsorption ratio (SAR) which makes it unsuitable for irrigation due to the infiltration problems risi0ng from unbalanced values of salinity and SAR. Combination of MBR effluent and RO effluent at respective proportions of 0.3:0.7 and 0.4:0.6 for AK-BWRO and AD-SWRO, respectively, are the optimum mixing ratios to overcome the infiltration hazard problem. Choice of less-sensitive crops to chloride and sodium ions is another strategy to overcome all hazards which may arise from above suggested mixing proportions.
显示更多 [+] 显示较少 [-]Haze and health impacts in ASEAN countries: a systematic review 全文
2018
Ramakreshnan, Logaraj | Aghamohammadi, Nasrin | Fong, ChngSaun | Bulgiba, Awang | Zaki, RafdzahAhmad | Wong, LiPing | Sulaiman, NikMeriam
Seasonal haze episodes and the associated inimical health impacts have become a regular crisis among the ASEAN countries. Even though many emerging experimental and epidemiological studies have documented the plausible health effects of the predominating toxic pollutants of haze, the consistency among the reported findings by these studies is poorly understood. By addressing such gap, this review aimed to critically highlight the evidence of physical and psychological health impacts of haze from the available literature in ASEAN countries. Systematic literature survey from six electronic databases across the environmental and medical disciplines was performed, and 20 peer-reviewed studies out of 384 retrieved articles were selected. The evidence pertaining to the health impacts of haze based on field survey, laboratory tests, modelling and time-series analysis were extracted for expert judgement. In specific, no generalization can be made on the reported physical symptoms as no specific symptoms recorded in all the reviewed studies except for throat discomfort. Consistent evidence was found for the increase in respiratory morbidity, especially for asthma, whilst the children and the elderly are deemed to be the vulnerable groups of the haze-induced respiratory ailments. A consensual conclusion on the association between the cardiovascular morbidity and haze is unfeasible as the available studies are scanty and geographically limited albeit of some reported increased cases. A number of modelling and simulation studies demonstrated elevating respiratory mortality rates due to seasonal haze exposures over the years. Besides, evidence on cancer risk is inconsistent where industrial and vehicular emissions are also expected to play more notable roles than mere haze exposure. There are insufficient regional studies to examine the association between the mental health and haze. Limited toxicological studies in ASEAN countries often impede a comprehensive understanding of the biological mechanism of haze-induced toxic pollutants on human physiology. Therefore, the lack of consistent evidence among the reported haze-induced health effects as highlighted in this review calls for more intensive longitudinal and toxicological studies with greater statistical power to disseminate more reliable and congruent findings to empower the institutional health planning among the ASEAN countries.
显示更多 [+] 显示较少 [-]Method development for determination of migrated phthalate acid esters from polyethylene terephthalate (PET) packaging into traditional Iranian drinking beverage (Doogh) samples: a novel approach of MSPE-GC/MS technique 全文
2018
Kiani, Amin | Ahmadloo, Mahsa | Shariatifar, Nabi | Moazzen, Mojtaba | Baghani, AbbasNorouzian | Khaniki, GholamRezaJahed | Taghinezhad, Ali | Kouhpayeh, Amin | Mousavi Khaneghah, Amin | Ghajarbeygi, Peyman
In the current study, a novel magnetic solid phase extraction (MSPE) technique combined with a gas chromatography/mass spectroscopy (GC/MS) was developed to determine the phthalate ester content of bottled Doogh samples. Doogh is a yogurt-based drinking beverage, which is frequently consumed in Middle East and Balkans. It is produced by stirring yogurt in Chern separation machine and consists of substances such as water, yogurt, and salt in addition to aqueous extracts of native herbs. The magnetic multi-walled carbon nanotubes (MWCNT-Fe₃O₄) were used as adsorbents of phthalate acid esters (PAEs) due to a superior adsorption capability of hydrophobic compounds. In this context, the quantity of the extractable migrated phthalate esters (dibutyl phthalate (DBP), dimethyl phthalate (DMP), butyl benzyl phthalate (BBP), diethyl phthalate (DEP), di-N-octyl phthalate (DNOP), and bis (2-ethylhexyl) phthalate (DEHP)) from polyethylene terephthalate (PET) bottles into Doogh samples was measured. The correlation between the concentration of migrated PAEs and some factors such as the type of Doogh (gaseous and without gas), difference in brand (five brands), volume (1500 and 300 mL), and the storage time also was investigated. The migration level into Doogh samples was increased by incorporating of gas as well as increasing the volume of PET bottles. Also, with elaborating of storage time, the migration of some phthalates such as DEHP (the mean from 2419.85 ng L⁻¹ in the first week to 2716.15 ng L⁻¹ in the second month), DEP, and total phthalate was increased. However, no significant difference in concentrations of migrated phthalate esters among different examined brands was noted. Finally, the concentration of migrated PAEs from bottle into all the examined Doogh samples was below the defined standards by EPA; 6 μg/L for DEHP in drinking water. Graphical abstract ᅟ
显示更多 [+] 显示较少 [-]Utilization of waste cooking oil as an alternative fuel for Turkey 全文
2018
Arslan, Ridvan | Ulusoy, Yahya
This study is based on three essential considerations concerning biodiesel obtained from waste cooking oil: diesel engine emissions of biodiesel produced from waste cooking oil, its potential in Turkey, and policies of the Turkish government about environmentally friendly alternative fuels. Emission tests have been realized with 35.8 kW, four-cylinder, four-stroke, direct injection diesel tractor engine. Test results are compared with Euro non-road emission standards for diesel fuel and five different blends of biodiesel production from waste cooking oil. The results of the experimental study show that the best blends are B10 and B20 as they show the lowest emission level. The other dimensions of the study include potential analysis of waste cooking oil as diesel fuels, referring to fuel price policies applied in the past, and proposed future policies about the same issues. It was also outlined some conclusions and recommendations in connection with recycling of waste oils as alternative fuels.
显示更多 [+] 显示较少 [-]Fenton treatment of bio-treated fermentation-based pharmaceutical wastewater: removal and conversion of organic pollutants as well as estimation of operational costs 全文
2018
Cheng, Yunqin | Chen, Yunlu | Lu, Juncheng | Nie, Jianxin | Liu, Yan
The Fenton process is used as a tertiary treatment to remove organic pollutants from the effluent of bio-treated pharmaceutical wastewater (EBPW). The optimal and most appropriate Fenton conditions were determined by an orthogonal array test and single-factor experiments. The removal of chemical oxygen demand (COD) was influenced by the following factors in a descending order: H₂O₂/Fe(II) molar ratio > H₂O₂ dosage > reaction time. Under the most appropriate Fenton conditions (H₂O₂/Fe(II) molar ratio of 1:1, H₂O₂ dosage of 120 mg L⁻¹ and reaction time of 10 min), the COD and dissolved organic carbon (DOC) were removed with efficiencies of 62 and 53%, respectively, which met the national discharge standard (GB 21903-2008) for the Lake Tai Basin, China. However, the Fenton treatment was inadequate for removal of N compounds, and the removal of organic nitrogen led to an increment in N-NH₃ from 3.28 to 19.71 mg L⁻¹. Proteins and polysaccharides were completely removed, and humic acids (HAs) were partly removed with an efficiency of 55%. Three-dimensional excitation/emission matrix spectra (3DEEMs) indicated complete removal of fulvic acid-like substances and 90% reduction in the florescence intensity of humic acid-like substances. Organic pollutants with molecular weights (MW) > 10 kDa were completely removed, MW 5–10 kDa were degraded into smaller MW ones, and some low molecular weight acids (MW 0.1–1 kDa) were mineralized during the Fenton process. Some species, including pharmaceutical intermediates and solvents were detected by gas chromatography-mass spectrometry (GC-MS). The operational costs of the Fenton’s treatment were estimated to be 0.58 yuan RMB/m³ EBPW based on reagent usage and iron sludge treatment and disposal.
显示更多 [+] 显示较少 [-]Electrokinetic-Fenton remediation of organochlorine pesticides from historically polluted soil 全文
2018
Ni, Maofei | Tian, Shulei | Huang, Qifei | Yang, Yanmei
Soil contamination by persistent organic pollutants (POPs) poses a great threat to historically polluted soil worldwide. In this study, soils were characterized, and organochlorine pesticides contained in the soils were identified and quantified. Individual electrokinetic (IE), EK-Fenton-coupled technologies (EF), and enhanced EK-Fenton treatment (E-1, E-2, and E-3) were applied to remediate soils contaminated with hexachloro-cyclohexane soprocide (HCH) and dichloro-diphenyl-trichloroethane (DDT). Variation of pH, electrical conductivity, and electroosmotic flow was evaluated during the EK-Fenton process. The IE treatment showed low removal efficiency for HCHs (30.5%) and DDTs (25.9%). In the EF treatment, the highest removal level (60.9%) was obtained for α-HCH, whereas P,P-DDT was the lowest (40.0%). Low solubility of pollutants impeded the HCH and DDT removal. After enhanced EK-Fenton treatment, final removal of pollutants decreased as follows: β-HCH (82.6%) > γ-HCH (81.6%) > α-HCH (81.2%) > δ-HCH (80.0%) > P,P-DDD (73.8%) > P,P-DDE (73.1%) > P,P-DDT (72.6%) > O,P-DDT (71.5%). The results demonstrate that EK-Fenton is a promising technology for POP removal in historically polluted soil.
显示更多 [+] 显示较少 [-]Decomposing the decoupling of CO2 emissions from economic growth in Cameroon 全文
2018
Engo, Jean
This paper applied the Tapio and LMDI methods based on an extended Kaya identity, to evaluate the decoupling and factors that influenced the relationship between economic growth and CO₂ emissions in Cameroon from 1990 to 2015. The analysis covered the two main sectors of Cameroon’s economic activity, and the decoupling indicators were broken down into five factors. The results showed that Cameroon performed weak decoupling throughout this study period. A weak negative decoupling and a strong negative decoupling appeared during the periods 1990–1992 and 1993–1994, whereas a strong decoupling occurred only from 1994 to 1995 and between 2004 and 2006. From a general point of view, we found that demographic change, followed by energy intensity and economic activity, played a negative role in decoupling, while economic structure and emission factors had promoted the development of decoupling. A comparative analysis of the industrial and tertiary sectors revealed that industrial growth determined the degree of decoupling of CO₂ emissions from Cameroon’s economic growth. The policy will need to optimize and significantly adjust the energy and industrial structures if Cameroon’s 2035 emission reduction targets are to be reached. This requires a change in Cameroon’s energy consumption and economic development pathways for optimal outcomes.
显示更多 [+] 显示较少 [-]Risk of exposure to total and inorganic arsenic by meat intake among different age groups from Brazil: a probabilistic assessment 全文
2018
Azevedo, Lucas Silva | Pestana, Inacio Abreu | Meneguelli-Souza, Annaliza Carvalho | Ramos, Bruno | Pessanha, Daniel Ribeiro | Caldas, Dayana | Almeida, Marcelo Gomes | de Souza, Cristina Maria Magalhaes
Beef and poultry as well as cattle and chicken livers are staple food items for Brazilian population, and previous studies had detected arsenic levels in these foods. This study aims to evaluate the risk of exposure to total and inorganic arsenic by meat intake in three age groups from Brazil (11–16, 16–21, and > 21 years). Our hypotheses are (i) that there is differences in the risk of exposure between age groups and (ii) the older individuals (> 21 years) are under higher risk. To test these hypotheses, we calculated the probabilistic estimated daily intake of total As (TAsᴱᴰᴵ) from poultry, beef, cattle liver, and chicken liver, and the probabilistic estimated incremental lifetime skin, bladder, and lung cancer risk (ILCR) associated with inorganic As ingestion from poultry only. TAsᴱᴰᴵ and ILCR from poultry differed among groups which confirm the first hypothesis. However, TAsᴱᴰᴵ and ILCR results cannot support the second hypothesis. Even though the age groups are under a low risk of exposure to As by meat intake, the results indicate that bladder/lung cancer risk (from poultry intake) slightly exceeds the safe limits in the older population.
显示更多 [+] 显示较少 [-]Modes of selenium occurrence and LCD modeling of selenite desorption/adsorption in soils around the selenium-rich core, Ziyang County, China 全文
2018
Zhang, Yu | Wu, Siyuan | Zheng, Hong | Weng, Liping | Hu, Yajie | Ma, Hongwen
Studying the modes of selenium occurrence in high-Se soils and its behaviors can improve understanding and evaluating its cycling, flux, and balance in geo-ecosystems and its influence on health. In this paper, using a modified sequential chemical extraction technique, seven operationally defined selenium fractions and Se valence distribution were determined about five soils in which paddy was planted (W1, W2, W3, W4, W5) and five soils in which maize was planted (H1, H2, H3, H4, H5) around the selenium-rich core, Ziyang County, Shaanxi Province, China. The results show that selenium fractions in the soils mainly include sulfide/selenide and base-soluble Se, and ligand-exchangeable Se is also high for five soils in which paddy was planted. For water-soluble Se, Se (IV) is main Se valence and almost no Se (VI) was determined about five soils in which paddy was planted, while almost 1:1 of Se (IV) and Se (VI) coexist about five soils in which maize was planted. For exchangeable Se, similar results were found. For the first time, two typical high-Se soils (W1 soil and H1 soil) were chosen to measure the pH-dependent solid-solution distribution of selenite in the pH range 3–9, and the results were explained using LCD (ligand and charge distribution) adsorption modeling. The desorbed selenite concentrations from the two soils are in general underestimated by the model due to a comparable binding affinity of phosphate and selenite on goethite and much lower amount of total selenite than total reactively adsorbed phosphate. The pH dependency of adsorption of selenite added to the soil can be successfully described with the LCD model for W1 soil. Whereas considering the influence of Al-oxides, by lowering selenite adsorption affinity constant K of Se adsorption on goethite by 16 times, the LCD model can describe the adsorption much better. The results can help to understand selenium cycling, flux, and balance in typical high-Se soils.
显示更多 [+] 显示较少 [-]Effect of dietary phytogenics (herbal mixture) supplementation on growth performance, nutrient utilization, antioxidative properties, and immune response in broilers 全文
2018
Saleh, Ahmed A. | Ebeid, Tarek A. | Abudabos, Alaeldein M.
This experiment was conducted to study that effect of a phytogenics (herbal mixture) supplementation as alternative to antibiotics on the growth performance and immune response in broilers. Three thousand broiler male chicks at 1 day of age were housed in floor pens and divided into five experimental groups with five replicates of 120 birds each. The first group was fed the basal diet without any additive in feed or water; the second group was fed the basal diet, and the drinking water was supplemented with mixture of antibiotics (Doxycycline 1 g/5 L + Colistine sulfate 1 g/5 L) for the first 10 days of life. The other three treatments of chickens were fed the control diet supplemented with herbal mixture at a level of 0.5, 1.0, and 1.5 kg/ton, respectively. Dietary herb mixture supplementation improved growth performance significantly in comparison with control group. In addition, herb mixture supplementation reduced plasma total cholesterol and triglycerides concentrations, whereas, high density lipoprotein HDL-cholesterol and glutathione peroxidase (GPX) were increased significantly. Furthermore, herb mixture supplementation increased plasma levels of total protein and antibodies titers for Newcastle disease virus before and after the infection. It could be concluded that dietary herb mixture supplementation had positive effects on growth performance, antioxidative properties, and humoral immunity in broiler chickens.
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