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1.
Molecules ; 26(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34833881

RESUMO

This study investigated acid splitting wastewater (ASW) and interphase (IF) from soapstock splitting, as well as matter organic non glycerol (MONG) from glycerol processing, as potential substrates for biogas production. Batch and semicontinuous thermophilic anaerobic digestion experiments were conducted, and the substrates were preliminary treated using commercial enzymes kindly delivered by Novozymes A/C. The greatest enhancement in the batch digestion efficiency was achieved when three preparations; EversaTransform, NovoShape, and Lecitase were applied in the hydrolysis stage, which resulted in the maximum methane yields of 937 NL/kg VS and 915 NL/kg VS obtained from IF and MONG, respectively. The co-digestion of 68% ASW, 16% IF, and 16% MONG (wet weight basis) performed at an organic loading rate (OLR) of 1.5 kg VS/m3/day provided an average methane yield of 515 NLCH4/kg VSadded and a volatile solid reduction of nearly 95%. A relatively high concentration of sulfates in the feed did not significantly affect the digestion performance but resulted in an increased hydrogen sulfide concentration in the biogas with the peak of 4000 ppm.


Assuntos
Metano/biossíntese , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Anaerobiose/fisiologia , Biocombustíveis/análise , Reatores Biológicos , Brassica napus/metabolismo , Glicerol/metabolismo , Hidrólise , Resíduos Industriais/economia , Resíduos Industriais/prevenção & controle , Águas Residuárias/análise
2.
J Food Sci ; 86(10): 4678-4690, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34519371

RESUMO

The annual output of salted duck egg white (SDEW) is estimated to be over 1.5 million tons in China, most of which is discarded due to high salt content. This has led to serious waste and environmental impact. Therefore, we developed an eco-friendly biocoagulation separation technology by combining chitosan and sodium alginate in order to produce a novel iron-binding peptide (DPs-Fe2+) from SDEW. The structure of DPs-Fe2+ was characterized by ultraviolet-visible spectroscopy, fluorescence spectroscopy, and Fourier transform infrared spectroscopy, followed by measuring DPs-Fe2+ response in a simulated digestion/Caco-2 cell model. Results showed that chitosan and sodium alginate complex could remove 91.21% of salt from SDEW, and the protein recovery rate reached 95.50%. Characterization results indicated that DPs bonded with Fe2+ to form a soluble chelate. Moreover, Caco-2 cell monolayer model indicated that the transport rate of Fe2+ was as high as 10.02% at 0.1 mg/ml concentration of digested chelates. The results demonstrate the potential application of DPs as a novel carrier for enhancing iron absorption. This research contributes to the development of an effective industrial desalination method and highlights an opportunity for recycling an otherwise discarded processing byproduct. PRACTICAL APPLICATION: Salted duck egg whites (SDEW) are the primary byproduct of salted egg yolk production, most of which is discarded due to high salt content. Hence, efficient utilization of the high-value proteins in SDEW is an urgent problem that must be resolved. Herein, we developed an effective industrial desalination method by combining chitosan and sodium alginate, which achieved excellent SDEW desalination and protein recovery. Furthermore, we produced a novel iron-binding peptide (DPs-Fe2+), which enhanced the transportation and absorption of Fe2+ in Caco-2 cell model, suggesting its potential as an iron supplement.


Assuntos
Patos , Clara de Ovo , Resíduos Industriais , Ferro , Peptídeos , Animais , Células CACO-2 , Sistemas de Liberação de Medicamentos/tendências , Clara de Ovo/química , Humanos , Resíduos Industriais/prevenção & controle , Ferro/química , Peptídeos/química
3.
Biomed Pharmacother ; 142: 112018, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34449317

RESUMO

The processing of tomato fruit into puree, juices, ketchup, sauces, and dried powders generates a significant amount of waste in the form of tomato pomace, which includes seeds and skin. Tomato processing by-products, particularly seeds, are reservoirs of health-promoting macromolecules, such as proteins (bioactive peptides), carotenoids (lycopene), polysaccharides (pectin), phytochemicals (flavonoids), and vitamins (α-tocopherol). Health-promoting properties make these bioactive components suitable candidates for the development of novel food and nutraceutical products. This review comprehensively demonstrates the bioactive compounds of tomato seeds along with diverse biomedical activities of tomato seed extract (TSE) for treating cardiovascular ailments, neurological disorders, and act as antioxidant, anticancer, and antimicrobial agent. Utilization of bioactive components can improve the economic feasibility of the tomato processing industry and may help to reduce the environmental pollution generated by tomato by-products.


Assuntos
Compostos Fitoquímicos/química , Extratos Vegetais/química , Solanum lycopersicum/química , Animais , Suplementos Nutricionais , Indústria Alimentícia/economia , Humanos , Resíduos Industriais/economia , Resíduos Industriais/prevenção & controle , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Sementes , Gerenciamento de Resíduos/métodos
4.
PLoS One ; 16(3): e0247452, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33651835

RESUMO

The treatability of seven wastewater samples generated by a textile digital printing industry was evaluated by employing 1) anammox-based processes for nitrogen removal 2) microalgae (Chlorella vulgaris) for nutrient uptake and biomass production 3) white-rot fungi (Pleurotus ostreatus and Phanerochaete chrysosporium) for decolorization and laccase activity. The biodegradative potential of each type of organism was determined in batch tests and correlated with the main characteristics of the textile wastewaters through statistical analyses. The maximum specific anammox activity ranged between 0.1 and 0.2 g N g VSS-1 d-1 depending on the sample of wastewater; the photosynthetic efficiency of the microalgae decreased up to 50% during the first 24 hours of contact with the textile wastewaters, but it improved from then on; Pleurotus ostreatus synthetized laccases and removed between 20-62% of the colour after 14 days, while the enzymatic activity of Phanerochaete chrysosporium was inhibited. Overall, the findings suggest that all microbes have great potential for the treatment and valorisation of textile wastewater after tailored adaptation phases. Yet, the depurative efficiency can be probably enhanced by combining the different processes in sequence.


Assuntos
Purificação da Água/métodos , Compostos de Amônio/análise , Compostos de Amônio/química , Compostos de Amônio/metabolismo , Biodegradação Ambiental , Biomassa , Chlorella vulgaris/metabolismo , Resíduos Industriais/análise , Resíduos Industriais/prevenção & controle , Microalgas/metabolismo , Phanerochaete/metabolismo , Pleurotus/metabolismo , Indústria Têxtil/tendências , Águas Residuárias/análise , Águas Residuárias/química
5.
Science ; 369(6506): 910-911, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32820108
6.
J Hazard Mater ; 393: 122338, 2020 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-32120208

RESUMO

Acid and metalliferous drainage (AMD) remains a challenging issue for the mining sector. AMD management strategies have attempted to shift from treatment of acid leachates post-generation to more sustainable at-source prevention. Here, the efficacy of microbial-geochemical at-source control approach was investigated over a period of 84 weeks. Diverse microbial communities were stimulated using organic carbon amendment in a simulated silicate-containing sulfidic mine waste rock environment. Mineral waste in the unamended leach system generated AMD quickly and throughout the study, with known lithotrophic iron- and sulfur-oxidising microbes dominating column communities. The organic-amended mineral waste column showed suppressed metal dissolution and AMD generation. Molecular DNA-based next generation sequencing confirmed a less diverse lithotrophic community in the acid-producing control, with a more diverse microbial community under organic amendment comprising organotrophic iron/sulfur-reducers, autotrophs, hydrogenotrophs and heterotrophs. Time-series multivariate statistical analyses displayed distinct ecological patterns in microbial diversity between AMD- and non-AMD-environments. Focused ion beam-TEM micrographs and elemental mapping showed that silicate-stabilised passivation layers were successfully established across pyrite surfaces in organic-amended treatments, with these layers absent in unamended controls. Organic amendment and resulting increases in microbial abundance and diversity played an important role in sustaining these passivating layers in the long-term.


Assuntos
Bactérias/metabolismo , Resíduos Industriais/prevenção & controle , Ferro/química , Mineração/métodos , Sulfetos/química , Bactérias/classificação , Bactérias/genética , Técnicas de Tipagem Bacteriana , Compostos Férricos/química , Sequenciamento de Nucleotídeos em Larga Escala , Concentração de Íons de Hidrogênio , Oxirredução , Silicatos/química , Microbiologia do Solo
7.
J Hazard Mater ; 387: 121668, 2020 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-31784132

RESUMO

In recent years, photoelectrocatalysis (PEC) for the treatment of industrial wastewaters (IWWs) has been repeatedly proposed. However, despite the number of tests reported in literature, only a few of them were conducted on real IWWs. In this study, real pharmaceutical IWWs showing an intense recalcitrant color were treated by PEC and H2O2-assisted PEC (UV/TiO2/Bias and UV/H2O2/TiO2/Bias, respectively) on TiO2 meshes having sub-micrometric features obtained by Plasma Electrolytic Oxidation. Photolysis (UV), chemical oxidation (H2O2) and H2O2-assisted photolysis (UV/H2O2) were tested in the same reactor for comparison. The configuration UV/H2O2/TiO2/bias showed the best results in term of decolorization efficiency and rate, where decolorization was 55 % (single-step H2O2 dosing) and 44 % (three-step H2O2 dosing), after 2 h of contact time. In the same contact time, UV and UV/TiO2/Bias processes did not give decolorization. A more effective COD removal was measured for the PEC processes, UV/H2O2/TiO2/Bias (-24 %) and UV/TiO2/Bias (-20 %), while COD removal by UV was almost 0 %. Correspondingly, the SOUR values showed that PEC combined with a single-step H2O2 dosage was the most effective configuration, leading to the highest biodegradability of the treated IWW with respect to the other processes. The energy consumption analysis demonstrated that PEC+H2O2 (single-step dosage) optimized energy costs.


Assuntos
Peróxido de Hidrogênio/química , Resíduos Industriais/prevenção & controle , Titânio/química , Águas Residuárias/química , Purificação da Água/métodos , Catálise , Eletroquímica/métodos , Luz , Oxirredução , Titânio/efeitos da radiação
8.
Prep Biochem Biotechnol ; 50(4): 317-329, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31755822

RESUMO

Azo dyes are recalcitrant compounds used as a colorant in various industries. The pollution caused by their extensive usage has adversely affected the environment for years. The existing physicochemical methods for dye pollution remediation are rather inefficient and hence there is a dearth of low-cost, potential systems capable of dye degradation. The current research studies the biodegradation potential of immobilized bacterial cells against azo dyes Reactive Orange 16 (RO-16) and Reactive Blue 250 (RB-250). Two indigenous dye degrading bacteria Bacillus sp. VITAKB20 and Lysinibacillus sp. KPB6 was isolated from textile sludge sample. Free cells of Bacillus. sp. VITAKB20 degraded 92.38% of RO-16 and that of Lysinibacillus sp. KPB6 degraded 95.36% of RB-250 within 72 h under static conditions. Upon immobilization with calcium alginate, dye degradation occurred rapidly. Bacillus. sp. VITAKB20 degraded 97.5% of RO-16 and Lysinibacillus sp. KPB6 degraded 98.2% of RB-250 within 48 h under shaking conditions. Further, the nature of dye decolorization was biodegradation as evident by high-performance liquid chromatography (HPLC), and Fourier-transform infrared spectroscopy (FTIR) results. Phytotoxicity and biotoxicity assays revealed that the degraded dye products were less toxic in nature than the pure dyes. Thus, immobilization proved to be a highly likely alternative treatment for dye removal.


Assuntos
Compostos Azo/metabolismo , Bacillaceae/metabolismo , Bacillus/metabolismo , Células Imobilizadas/metabolismo , Corantes/metabolismo , Alginatos/química , Animais , Artemia/metabolismo , Bacillaceae/química , Bacillus/química , Biodegradação Ambiental , Resíduos Industriais/prevenção & controle , Vigna/metabolismo
9.
Prep Biochem Biotechnol ; 49(6): 567-577, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30929621

RESUMO

Polyhydroxyalkanoates (PHAs) are intracellular carbon and energy storage reserve material stored by gram-negative bacteria under nutrient limitation. PHAs are best alternative biodegradable plastics (bio-plastics) due to their resemblance to conventional synthetic plastic. The present study investigated the synergistic effect of nutritional supplements (amino acid and vitamin) on the PHA production by Alcaligenes sp. NCIM 5085 utilizing a sugar refinery waste (cane molasses) under submerged fermentation process. Initially, the effect of individual factor on PHA yield was studied by supplementing amino acids (cysteine, isoleucine, and methionine), vitamin (thiamin), and cane molasses at varying concentration in the production medium. Further, the cultivation medium was optimized by varying the levels of cane molasses, methionine and thiamin using response surface methodology to enhance the PHA yield. The maximum PHA yield of 70.89% was obtained under the optimized condition, which was then scaled up on 7.5 L-bioreactor. Batch cultivation in 7.5 L-bioreactor under the optimized condition gave a maximum PHA yield and productivity of 79.26% and 0.312 gL-1 h-1, respectively. The PHA produced was subsequently characterized as PHB by FTIR. PHB extracted was of relatively high molecular weight and crystallinity index. DSC analysis gave Tg, Tm, and Xc of 4.2, 179 °C and 66%, respectively. TGA analysis showed thermal stability with maximized degradation occurring at 302 °C, which is above the melting temperature (179 °C) of the purified polymer. The extracted polymer, therefore, possessed desirable material properties to be used in food packaging.


Assuntos
Aminoácidos/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Tiamina/metabolismo , Alcaligenes/metabolismo , Reatores Biológicos , Cisteína/metabolismo , Fermentação , Embalagem de Alimentos , Resíduos Industriais/prevenção & controle , Isoleucina/metabolismo , Metionina/metabolismo , Melaço , Peso Molecular , Poli-Hidroxialcanoatos/química , Temperatura de Transição , Gerenciamento de Resíduos/métodos
10.
Food Chem ; 289: 468-481, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30955638

RESUMO

Whey is a byproduct with nutritional value and high organic and saline content. It is an important source of organic contamination in dairy industry. In this paper, we gave an overview of the current use of membrane materials and membrane processing in cheese whey protein recovery and discussed recent developments in membrane technology. Different types of membranes, such as polymers, ceramic membranes and modification membranes, are used for various purposes, such an increasing permeation flux, reducing membrane fouling, and increasing the protein rejection rate, concentration, fractionation and purification of whey protein. New membrane processing methods and integrated membrane methods to recover whey protein were reviewed. Membrane fouling factors during whey protein ultrafiltration process, which included whey protein conformation, membrane filtration conditions and the interaction between proteins and the membrane surface or pores, were also discussed and analyzed to reveal membrane fouling mechanism.


Assuntos
Manipulação de Alimentos/instrumentação , Manipulação de Alimentos/métodos , Membranas Artificiais , Proteínas do Soro do Leite/isolamento & purificação , Queijo/análise , Indústria de Laticínios/métodos , Poluição Ambiental/prevenção & controle , Contaminação de Alimentos , Resíduos Industriais/prevenção & controle , Polímeros , Ultrafiltração/métodos , Purificação da Água , Soro do Leite
11.
Dalton Trans ; 47(47): 16828-16834, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30318546

RESUMO

Bio-waste in the form of chicken eggshells, which contain high amounts of calcium carbonate (CaCO3), is used to store energy. The fine eggshell powders are used as an electrode against a metallic lithium anode in a non-aqueous electrolyte. The initial discharge capacitance of the eggshell system was found to be 232 F g-1, while the reversible capacitance was 120 F g-1. Thereon, the cell maintained an excellent capacitance retention of 92% over 1000 cycles. The electrochemical performance obtained is comparable to that of commercially available classical activated carbon (AC) material. CaCO3 showed a non-faradaic behaviour and the shape of the electrochemical curves resembles that of the AC electrode. The preliminary findings suggest that CaCO3 from eggshells can be used as the electrode in Li-ion capacitors to store and release charges effectively over a wide electrochemical stability window of 4 V. Using chicken eggshells in this manner not only reduces the amount of bio-waste, but also adds considerable value. A detailed understanding of the electrochemical and physical behaviour of the material is needed in order to improve its performance and to enable its widespread use.


Assuntos
Carbonato de Cálcio/química , Casca de Ovo/química , Resíduos Industriais/prevenção & controle , Resíduos , Animais , Carbono/química , Capacitância Elétrica , Técnicas Eletroquímicas , Eletrodos , Eletrólitos , Lítio/química , Porosidade , Difração de Raios X
12.
Chemosphere ; 209: 201-219, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29933158

RESUMO

The effluent discharged by the textile dyehouses has a seriously detrimental effect on the aquatic environment. Some dyestuffs produce toxic decomposition products and the metal complex dyes release toxic heavy metals to watercourses. Of the dyes used in the textile industry, effluents containing reactive dyes are the most difficult to treat because of their high water-solubility and poor absorption into the fibers. A range of treatments has been investigated for the decolorization of textile effluent and the adsorption seems to be one of the cheapest, effective and convenient treatments. In this review, the adsorbents investigated in the last decade for the treatment of textile effluent containing reactive dyes including modified clays, biomasses, chitin and its derivatives, and magnetic ion-exchanging particles have been critically reviewed and their reactive dye binding capacities have been compiled and compared. Moreover, the dye binding mechanism, dye sorption isotherm models and also the merits/demerits of various adsorbents are discussed. This review also includes the current challenges and the future directions for the development of adsorbents that meet these challenges. The adsorption capacities of adsorbents depend on various factors, such as the chemical structures of dyes, the ionic property, surface area, porosity of the adsorbents, and the operating conditions. It is evident from the literature survey that decolorization by the adsorption shows a great promise for the removal of color from dyehouse effluent. If biomasses want to compete with the established ion-exchange resins and activated carbon, their dye binding capacity will need to be substantially improved.


Assuntos
Corantes/isolamento & purificação , Resíduos Industriais/prevenção & controle , Indústria Têxtil/métodos , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Corantes/química , Troca Iônica , Poluentes Químicos da Água/análise
13.
Water Environ Res ; 90(5): 395-408, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29678211

RESUMO

Iron and steel industry is the principal driving force propelling economic and technological growth of a nation. However, since its inception this industry is associated with widespread environmental pollution and enormous water consumption. Different units of a steel plant discharge effluents loaded with toxic, hazardous pollutants, and unutilized components which necessitates mitigation. In this paper, pollutant removal efficiency, effluent volume product quality, and economic feasibility of existing treatments are studied vis-à-vis their merits, demerits, and innovations to access their shortcomings which can be overcome with new technology to identify future research directions. While conventional methods are inadequate for complete remediation and water reclamation, the potential of advanced treatments, like membrane separation, remains relatively untapped. It is concluded that integrated systems combining membrane separation with chemical treatments can guarantee a high degree of contaminant removal, reusability of effluents concurrently leading to process intensification ensuring ecofriendliness and commercial viability.


Assuntos
Conservação dos Recursos Hídricos/métodos , Resíduos Industriais/prevenção & controle , Indústria Manufatureira , Poluição Química da Água/prevenção & controle , Ferro , Aço
14.
Chemosphere ; 199: 569-584, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29455126

RESUMO

This study investigated the occurrence, removal and influence of plant-operating conditions on removal mechanisms of 83 VOCs in different treatment units of a CETP in Mumbai, treating industrial waste on primary and secondary level. A mass balance approach was used to predict VOC removal by volatilization, stripping, weir drop, adsorption, and biodegradation. Results indicate that ∼17% of VOCs were removed by stripping in equalization tank and ∼8% were removed by weir drop in primary clari-flocculator respectively. Biodegradation was the dominant mechanism in aeration tank and was relatively poor for hydrophobic compounds which were more vulnerable to removal by stripping. Stripping rates could be reduced by increasing the active biomass concentration and using fine pore diffusers to reduce the air/effluent ratio. Decrease in Henry's constant and compound concentration can shift the main removal mechanism from stripping to biodegradation. Results also show considerable agreement between measured (71.2%) and predicted (67.1%) total removal, especially in aeration tanks. Equalization tanks (actual, 20.5%, predicted, 16.9%), primary clari-flocculator (actual, 14.2%, predicted, 7.7%), and secondary clarifier units (actual, 29.5%, predicted, 16.8%) showed fairly acceptable differences in measured and predicted removal. The effect of other mechanisms on VOC removal need to be further explored owing to their major contribution to VOC removal. This study is the first attempt in understanding the mechanisms behind the removal of VOCs in each treatment unit, especially equalization tanks and clarifier units, which have been severely underestimated till date.


Assuntos
Biodegradação Ambiental , Resíduos Industriais/prevenção & controle , Compostos Orgânicos Voláteis/isolamento & purificação , Biomassa , Resultado do Tratamento , Volatilização
15.
Chemosphere ; 198: 59-67, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29421761

RESUMO

Inappropriate treatments for the effluents from semiconductor plants might cause the releases and wide distributions of selenium (Se) into the ecosystems. In this study, Al/Si and Fe/Si coprecipitates were selected as model adsorbents as they often formed during the wastewater coagulation process, and the removal efficiency of selenite (SeO3) and selenate (SeO4) onto the coprecipitates were systematically examined. The removal efficiency of SeO3 and SeO4 was highly related to surface properties of Al/Si and Fe/Si coprecipitates. The surface-attached Al shell of Al/Si coprecipitates shielded a portion of negative charges from the core SiO2, resulting in a higher point of zero charge than that of Fe/Si coprecipitates. Thus, adsorption of SeO3/SeO4 was favorable on the Al/Si coprecipitates. Adsorptions of both SeO3 and SeO4 on Al/Si coprecipitates were exothermic reactions. On Fe/Si coprecipitates, while SeO3 adsorption also showed the exothermic behavior, SeO4 adsorption occurred as an endothermic reaction. The kinetic adsorption data of SeO3/SeO4 on Al/Si and Fe/Si coprecipitates were described well by the pseudo-second-order kinetic model. SeO4 and SeO3 adsorption on Fe/Si or Al/Si were greatly inhibited by the strong PO4 ligand, whereas the weak ligand such as SO4 only significantly affected SeO4 adsorption. The weakest complex between SeO4 and Al was implied by the essentially SeO4 desorption as SeO4/PO4 molar ratios decreased from 0.5 to 0.2. These results were further confirmed by the less SeO4 desorption (41%) from Fe/Si coprecipitates than that from Al/Si coprecipitates (78%) while PO4 was added sequentially.


Assuntos
Resíduos Industriais/prevenção & controle , Selênio/química , Semicondutores , Adsorção , Alumínio/química , Precipitação Química , Resíduos Industriais/análise , Ferro/química , Cinética , Ácido Selênico/isolamento & purificação , Ácido Selenioso/isolamento & purificação , Propriedades de Superfície , Poluentes Químicos da Água/isolamento & purificação
16.
Int J Biol Macromol ; 112: 383-389, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29408678

RESUMO

The pectin gel has been proved to be an effective material for methylene blue (MB) removal, but it presented low adsorption rate. To get over the vice, the pectin microgel particles (PMP) was prepared. No matter high or low initial MB concentration, the PMP presented high adsorption rate with equilibrium time of 20min. The adsorption process based on monolayer adsorption and adsorbance of 284.09mg/g was obtained. What's more, the adsorption process was electrostatic adsorption with mean free energy of 74.223kJ/mol. The pseudo-second-order kinetic model fitted perfectly to the experimental data. The MB uptake was controlled by film diffusion mechanism. Furthermore, the recovery efficiency of regenerated PMP were higher than 80% after three cycles. The present study showed the PMP presented acceptable adsorbance, high adsorption rate and recovery efficiency. Thus, we believe that the PMP was a promising candidate for MB cleanup.


Assuntos
Corantes/isolamento & purificação , Azul de Metileno/isolamento & purificação , Pectinas/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Corantes/toxicidade , Conservação dos Recursos Naturais , Humanos , Resíduos Industriais/prevenção & controle , Cinética , Azul de Metileno/toxicidade , Soluções/química , Termodinâmica , Poluentes Químicos da Água/toxicidade , Purificação da Água/métodos
17.
Ann Glob Health ; 84(2): 285-291, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-30873779

RESUMO

BACKGROUND: Traditional ceramics are a cultural heritage in Mexico, used by the general population in everyday life. These ceramics are glazed with lead oxide and are usually produced in households that share living and working spaces. Glazing is usually performed by women, and children are not restrained from the work space and frequently help, resulting in high levels of lead exposure for all. Interventions that promote a change in technology (such as lead-free glazes or efficient kilns) are often unrealistic for potters with fewer economic resources who depend on their production as their main income. Interventions focusing on exposure prevention (rather than a technology change) at the household level are scarce. METHODS: Working hand-in-hand with a group of nine women, lay community workers, promotoras, from Santa Fe de Laguna, Michoacán, we developed a program focusing on the self-recognition of health risks. The program was composed of health education (including a lead in blood and bone measurement for women), health/work risk recognition and communication to the community, and work/living area reorganization and remediation in three stages: work with 1) promotoras, 2) their extended families, and 3) their community, including talks in elementary schools. RESULTS: The promotoras developed and distributed risk communication graphic materials and delivered a lead-awareness talk in the Purhepecha language, in the local primary health-care clinic and three elementary schools. Lead in bone levels had a mean ± SD (min, max) of rotula: 84.8 µg/g ± 68.9 (23.89, 214.2), tibia 93.2 µg/g 81.2 (14.23, 261.21). We implemented safer and cleaner ceramic production in the promotoras workshops.Public Health Relevance: Environmental and occupational exposures can be reduced through programs that are tailored by and for a specific community. When there is no evident alternative technology for safer production, such programs can empower groups and lead to reduced exposure for their children, family and community.


Assuntos
Cerâmica , Exposição Ambiental , Educação em Saúde , Resíduos Industriais , Chumbo , Óxidos , População Rural , Adulto , Cerâmica/efeitos adversos , Cerâmica/análise , Cerâmica/química , Criança , Pesquisa Participativa Baseada na Comunidade , Exposição Ambiental/efeitos adversos , Exposição Ambiental/prevenção & controle , Características da Família , Feminino , Educação em Saúde/métodos , Educação em Saúde/organização & administração , Humanos , Resíduos Industriais/efeitos adversos , Resíduos Industriais/análise , Resíduos Industriais/prevenção & controle , Chumbo/efeitos adversos , Chumbo/análise , México/epidemiologia , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/prevenção & controle , Óxidos/efeitos adversos , Óxidos/análise , Avaliação de Programas e Projetos de Saúde
18.
Ann Glob Health ; 84(2): 292-299, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-30873789

RESUMO

BACKGROUND: The World Health Organization (WHO) estimates that 25% of global morbidity and one-third of childhood morbidity may be attributable to environment. Low and high-income countries displayed different environmental risks. Mexico demonstrates the necessity for creating a national environmental health program. In southeastern Mexico, Tixméhuac, is a Mayan community with a high marginalization degree and social backwardness. The main childhood morbidities are acute and chronic diseases. OBJECTIVE: The aim of the study was to recognize environmental risks for children's health in Tixméhauc, Yucatan State. METHODS: A total of one hundred children under five years old participated. To identify the environmental risks at home, items from the Green Sheet Guidance (WHO), Salamanca General Survey and Environmental Clinical History were used. To know the prevalence of respiratory diseases and asthma, the International Study of Asthma and Allergies in Children (ISAAC) survey was used. Potentially hazardous sites were identified partially using the Methodology for Identification and Evaluation of Health Hazards in Contaminated Sites from the Pan American Health Organization (PAHO). FINDINGS: The low stature of, malnutrition, presence of wheezing and asthma symptoms in children were higher than expected. The suspected cases of parasitosis and vector-borne disease occurred in 50% of the children. Indoor air quality perception was associated with respiratory pathology history; housing quality was related to suspected cases of vector-borne diseases; drinking water quality was linked to suspected cases of parasitosis. Risk areas in the community include agricultural activity, which has led to deposits of empty containers of agrochemicals and electronic waste among solid waste dump. CONCLUSION: This study presents observed environmental risks to children in a low development country and in developing countries. The community has a low perception of the environmental risk. The need for public health programs reducing risks to children's environmental health is imperative.


Assuntos
Poluição do Ar em Ambientes Fechados , Saúde da Criança/estatística & dados numéricos , Exposição Ambiental , Saúde Ambiental , Doenças Parasitárias/epidemiologia , Doenças Respiratórias/epidemiologia , Agroquímicos/efeitos adversos , Agroquímicos/análise , Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , Pré-Escolar , Exposição Ambiental/efeitos adversos , Exposição Ambiental/prevenção & controle , Exposição Ambiental/estatística & dados numéricos , Saúde Ambiental/métodos , Saúde Ambiental/organização & administração , Feminino , Habitação , Humanos , Resíduos Industriais/efeitos adversos , Resíduos Industriais/análise , Resíduos Industriais/prevenção & controle , Masculino , México/epidemiologia , Morbidade , Determinação de Necessidades de Cuidados de Saúde , Medição de Risco/métodos , Fatores de Risco
19.
Environ Sci Pollut Res Int ; 24(25): 20372-20389, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28707240

RESUMO

Sealing layers made of two alkaline paper mill by-products, fly ash and green liquor dregs, were placed on top of 50-year-old sulfide-containing tailings as a full-scale remediation approach. The performance and effectiveness of the sealing layers with high water content for an oxygen barrier and low hydraulic conductivity for a sealing layer in preventing the formation of acid rock drainage were evaluated 5 years after the remediation. The leaching behavior of the covered tailings was studied using batch leaching tests (L/S ratio 10 L/kg). The leaching results revealed that, in general, the dregs- and ash-covered tailings released relatively lower concentrations of many elements contained in acid rock drainage compared to those from the uncovered tailings. A change in the chemical composition and mineralogical state of the tailings was observed for the tailings beneath the covers. The increase in pH caused by the alkaline materials promoted metal precipitation. Geochemical modeling using PHREEQC confirmed most of the geochemical changes of the covered tailings. Both the ash and dregs showed potential to function as sealing materials in terms of their geochemical properties. However, mobilization of Zn and Ni from the lower part of the dregs-covered tailings was observed. The same phenomenon was observed for the lower part of the ash-covered tailings. Ash showed advantages over dregs as a cover material; based on geochemical studies, the ash immobilized more elements than the dregs did. Lysimeters were installed below the sealing layers, and infiltrating water chemistry and hydrology were studied to monitor the amount and quality of the leachate percolating through.


Assuntos
Recuperação e Remediação Ambiental/métodos , Resíduos Industriais/análise , Mineração/métodos , Poluentes Químicos da Água/análise , Cinza de Carvão/química , Resíduos Industriais/prevenção & controle , Metais/análise , Modelos Teóricos , Papel , Sulfetos/química
20.
Chemosphere ; 185: 329-335, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28704664

RESUMO

Chlorine bleaching technology (C process, CEH process, H process and theirs combination), which was identified as a primary formation source of PCDD/Fs, is still widely used by the vast majority of Chinese non-wood pulp and paper mills (non-wood PMs). The purpose of this study was to provide information and data support for further eliminating dioxin for non-wood PMs in China, and especially to evaluate the PCDD/Fs release reduction for those mills converting their pulp bleaching processes from CEH to ECF. The PCDD/Fs concentrations of the bleached pulp and bleaching wastewater with ECF bleaching were in the ranges of 0.13-0.8 ng TEQ kg-1, and 0.15-1.9 pg TEQ L-1, respectively, which were far lower than those with CEH process, indicating that the ECF process is an effective alternative bleaching technology to replace CEH in Chinese non-wood PMs to reduce dioxin release. The release factor via flue gas of the alkali recovery boiler in Chinese non-wood PMs was first reported to be 0.092 µg TEQ Ad t-1 in this study. On the assumption that pulp bleaching processes of all Chinese non-wood PMs were converted from CEH to ECF, the annual release of PCDD/Fs via the bleaching wastewater and bleached pulp would be reduced by 79.1%, with a total of 1.60 g TEQ.


Assuntos
Compostos Clorados/química , Cloro/química , Óxidos/química , Dibenzodioxinas Policloradas/química , Águas Residuárias/análise , Benzofuranos , China , Dioxinas , Resíduos Industriais/prevenção & controle , Indústrias , Papel
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