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1.
Chemosphere ; 359: 142245, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38735498

ABSTRACT

This study aimed to evaluate the concentration, distribution, along with the environmental and human health impact of eight heavy metals-Pb, Cr, Cu, Cd, Zn, Mn, Ni, and As-on St. Martin's Island in the northeastern Bay of Bengal, and in doing so to help implement new legislations to protect the island. Focusing on the island's significance as a tourist destination, with seafood being a prominent dietary component, three sample types (sediment, seawater, and crustaceans) were selected for a comprehensive assessment, considering seasonal variations. Concentration of metals was observed to be lower than the established standards in sediment samples, but in seawater samples, Pb, Cr, Cd and Zn were higher than US-EPA values for natural marine water. The metals displayed a decreasing trend of Zn > Ni > Pb > Cu > Mn > As > Cd > Cr in crustacean samples for both seasons. Crustacean samples displayed higher metal concentrations in winter than in monsoon. Pb exceeded the maximum allowable limit for crustaceans with a concentration of about 3 and 4 mg kg-1 in monsoon and winter respectively; being more than 6-8 times the standard for Bangladesh which is only about 0.5 mg kg-1. Health indices displayed that although adults may suffer less from carcinogenic/non-carcinogenic health effects, the risks are far greater for children. For both age groups, As and Ni displayed possibilities of developing cancer. Principal Component Analysis (PCA)shed light on the sources of metals and showed that most of them were from anthropogenic sources. Overall, this study found that the quality of the environment of the island was better in comparison to previous studies made before the pandemic, and so, if the trend continues, it may lead to a better environment for the organisms around the island and help to keep the negative physiological impacts from the consumption of these organisms to a minimal.


Subject(s)
Bays , Environmental Monitoring , Islands , Metals, Heavy , Water Pollutants, Chemical , Water Pollutants, Chemical/analysis , Metals, Heavy/analysis , Animals , Humans , Bays/chemistry , Seawater/chemistry , Geologic Sediments/chemistry , Anthozoa/chemistry , India , Seasons , Metals/analysis , Seafood/analysis , Crustacea
2.
Environ Sci Pollut Res Int ; 30(32): 78294-78307, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37269521

ABSTRACT

Sulfidic copper tailings (SCTs) with excessive sulfur content are prone to oxidation, leading to the generation of sulfates and causing compatibility issues with cement. To address this problem, this paper proposes upcycling SCTs into alkali-activated slag (AAS) materials to fully utilize the produced sulfates for slag activation. The influence of the sulfur content of the SCTs compound (quartz, SCTs, and fine pyrite) on the properties of AAS was investigated from various aspects including setting time, compressive strength, hydration products, microstructure, and pore structure. The experimental results showed that adding SCTs compound enabled the generation of S-rich expansive products, such as ettringite, sodium sulfate, and gypsum. Moreover, nano-sized spherical particles were formed and well-distributed in pores or micro-cracks in the microstructure of AAS mortars. Consequently, AAS mortars with SCTs compound developed higher compressive strength at all ages than the blank ones, with an increase of 40.2-144.8% at 3 days, 29.4-115.7% at 7 days, and 29.3-136.3% at 28 days. Furthermore, AAS mortars with SCTs compounds enjoyed significant economic and environmental benefits, as demonstrated by cost-benefit and eco-efficiency analyses. The optimal sulfur content of the SCTs compound was found to be 15%.


Subject(s)
Alkalies , Copper , Alkalies/chemistry , Construction Materials , Sulfur , Sulfates
3.
J Biotechnol ; 366: 65-71, 2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36907357

ABSTRACT

Crude glycerol, a byproduct of biodiesel production, was utilized as a carbon source to produce microbial lipids by the oleaginous yeast Rhodotorula toruloides in this study. The maximum lipid production and lipid content were 10.56 g/L and 49.52%, respectively, by optimizing fermentation conditions. The obtained biodiesel met the standards of China, the United States, and the European Union. The economic value of biodiesel produced from crude glycerol increased by 48% compared with the sale of crude glycerol. In addition, biodiesel production from crude glycerol could reduce 11,928 tons of carbon dioxide emissions and 55 tons of sulfur dioxide emissions. This study provides a strategy for a closed loop of crude glycerol to biofuel and ensures sustainable and stable development of the biodiesel industries.


Subject(s)
Biofuels , Glycerol , Yeasts , Fermentation , Lipids
4.
Sci Total Environ ; 856(Pt 1): 158782, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36116636

ABSTRACT

Offshore wind power is a typical example of clean energy production and plays a critical role in achieving carbon neutrality. Offshore wind farms can have an impact on the marine environment, especially sedimentary environments, but their influence on sediments remain largely unknown. This study, which uses the control-impact principle to define different areas, investigated the characteristics of marine sediments under the Putidao offshore wind farm in Bohai Bay, China. We used chemical and microbiological observations to evaluate sediment quality and microbial community structure. According to both the geo-accumulation index (Igeo) and contamination factor (CF) indexes, copper, chromium and zinc were the major contaminants in the offshore wind farm sediments. The pollution load index (PLI) index showed that the various sites on the wind farm were only lightly polluted compared with baseline values. Closer to the wind farm's center, the metal concentrations started to rise. The physicochemical features of the sediments could better explain changes in the microorganisms present, and screening the microbiomes showed a correlation with heavy metal levels, linking the relative abundance of microorganisms to the sediment quality index. This comprehensive study fills a knowledge gap in China and adds to our understanding of how to assess the sedimentary environments of offshore wind farms.


Subject(s)
Metals, Heavy , Microbiota , Water Pollutants, Chemical , Environmental Monitoring , Water Pollutants, Chemical/analysis , Energy-Generating Resources , Wind , Geologic Sediments/chemistry , Metals, Heavy/analysis
5.
Rev. biol. trop ; 70dic. 2022.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1449471

ABSTRACT

Introducción: La generación de impactos negativos producto de proyectos de infraestructura o actividades de desarrollo generan pérdida de biodiversidad y reducción de la calidad de los servicios que el ambiente provee a sociedades humanas. Afortunadamente, muchos de esos impactos pueden ser reducidos, controlados o resarcidos por medio de medidas de mitigación, rehabilitación y compensación, que suelen sustentarse en el marco jurídico ambiental de los países o estados donde son implementados. Esta revisión provee una visión teórica del uso de compensación ambiental como instrumento jurídico/técnico integrado al manejo del entorno natural. Metodología: Realizamos una revisión de la literatura global sobre el tema mediante los buscadores de referencias GoogleScholar y SciELO empleando varios indicadores en inglés y español. Resultados: Un total de 244 referencias sobre compensación ambiental fueron encontradas, catalogadas y evaluadas, mostrándose un claro patrón de incremento del número de ellas en la última década. La compensación ambiental constituye un instrumento jurídico/técnico que permite resarcir por pérdidas ambientales y suele ser un componente de los Estudios de Impacto Ambiental regulado por el estado. Varias estrategias metodológicas son empleadas para establecer acciones compensatorias, cada una de ellas sustentada en alguno de cuatro enfoques posibles: económico, ecológico, político y cultural/social. Dentro del enfoque ecológico, se busca la equivalencia ecológica entre los elementos ambientales impactados y la compensación, procurando que no exista pérdida neta. Así, este enfoque tiene la ventaja de posibilitar la incorporación de múltiples criterios para la evaluación del daño y de las acciones de indemnización, por lo que es posible de aplicar en situaciones diversas. A pesar de su uso, la aplicación de medidas compensatorias no está exenta de crítica y hay situaciones en que la singularidad de los elementos impactados imposibilita un resarcimiento efectivo de las pérdidas. Conclusiones: La compensación tiene gran relevancia actualmente en la gestión ambiental y debe favorecer el derecho universal a un ambiente sano. Sin embargo, su aplicación efectiva requiere claridad en los procedimientos seguidos y una muy estrecha vigilancia prevenir pérdidas o incluso una ganancia neta ambiental.


Introduction: Infrastructure projects or development activities often generate a loss of biodiversity and reduce the quality of the environment's services to human societies. Fortunately, many of these impacts can be reduced, controlled, or compensated through mitigation, rehabilitation, and compensation measures, which usually rely on the environmental legal framework of the countries or states where they are implemented. This review provides a theoretical vision of using environmental compensation as a legal/technical instrument integrated into natural environment management. Methodology: We reviewed the global literature on the subject using the GoogleScholar and SciELO reference search engines using various indicators in English and Spanish. Results: We found 244 references on environmental compensation, showing a clear increasing pattern in the last decade. Environmental compensation constitutes a legal/technical instrument that allows offsets for environmental losses and often is part of the Environmental Impact Studies regulated by the state. Several methodological strategies are used to establish compensatory actions, each of them based on one of four possible approaches: economic, ecological, political, and cultural. The ecological equivalence between the impacted environmental elements and compensation is sought within the ecological approach, ensuring no net loss. Thus, this approach allows the incorporation of multiple criteria for the evaluation of damage and compensation actions: it can be applied in different situations. Nevertheless, compensatory measures are not exempt from criticism. There are situations in which the singularity of the impacted elements makes an adequate compensation for losses impossible. Conclusions: Compensation is highly relevant in environmental management and must favor the universal right to a healthy environment. However, its practical application requires clear procedures and close vigilance to prevent losses or even a net environmental gain.

6.
Front Psychol ; 13: 954402, 2022.
Article in English | MEDLINE | ID: mdl-36248581

ABSTRACT

The environmental quality and subjective environmental evaluations in urban open spaces are essential. In this study, the effects of building, green, and water landscapes, which are typical visual landscapes, on the subjective environmental evaluations (including thermal sensation and comfort, and overall comfort) in different seasons were analyzed by conducting questionnaire surveys and field measurements in a severely cold city. It was found that the visual landscapes significantly affected subjective environmental evaluations in winter and summer, but there were no effects in the transitional season. In summer, compared with the building and green landscape, the thermal sensation vote in the water landscape was the lowest at 0.4, and the differences were 0.3∼1.0. However, the thermal comfort vote in the water landscape was found to be 0.6 times higher. In winter, the thermal sensation and comfort votes in the water landscape were the lowest, the average evaluation under different UTCI was -2.2, and the results were similar for the overall comfort evaluation. In addition, the subjects believed that green and water landscapes improved thermal comfort and had more significant effects on improving the environmental temperature in the three seasons. Additionally, visual landscape evaluations significantly affect subjective environmental evaluations in summer than in the winter and transitional season; the higher the visual landscape evaluation, the better the thermal and overall comfort.

7.
Alzheimers Dement (N Y) ; 8(1): e12353, 2022.
Article in English | MEDLINE | ID: mdl-36204348

ABSTRACT

Introduction: The overarching goal of research on physical settings for individuals living with dementia is to identify associations between designed features within the built environment and outcomes of interest. Over the past three decades numerous environmental assessment tools have been developed in several countries, responding to a changing set of care industry values that increasingly prioritize a holistic, quality-of-life-driven person-centered care (PCC) model over a biomedical approach to long-term care (LTC) provision. This article reviews the diversity, constructs, strengths, and limitations of existing environmental assessment tools and identifies gaps for future tool development. Methods: A systematic literature search was conducted using four databases (Medline, CINAHL, PsycInfo, and Avery Index) and terms related to health-care environments and assessment tools. Results: A total of 13 environmental assessment tools for people living with dementia within shared residential settings were identified. Evaluation of the environmental assessment tools includes a synthesis of published data for each tool's reliability, validity, ease of use, interpretability, strengths and weaknesses, as well as a comparison of various tool characteristics including date of development, country of origin, applicable care setting(s), number and variety of measures and underlying constructs, format, and descriptive versus evaluative content. Discussion: While the shift to person-centered values encompasses all aspects of care and care settings, the majority of person-centered definitions exclude the important role of the designed, physical environment. However, this review of environmental assessment tools clearly demonstrates that newer tools are embracing the full array of PCC values. In the United States, this is shown in the shift from tools designed to assess segregated dementia care settings to tools that integrate the needs and preferences both of individuals living with and without dementia. Next-generation tools need to specifically address the household model of design. Highlights: The overarching goal of research on physical settings for individuals living with dementia is to identify associations between designed features within the built environment and outcomes of interest.A systematic literature search identified a total of 13 environmental assessment tools for people living with dementia within shared residential settings; these tools were then described and evaluated based on reliability, validity, ease of use, interpretability, strengths, and weaknesses.This review of environmental assessment tools clearly demonstrates that newer tools are embracing the full array of person-centered care values.

8.
Foods ; 10(8)2021 Aug 14.
Article in English | MEDLINE | ID: mdl-34441657

ABSTRACT

Mangrove wetlands provide essential ecosystem services such as coastal protection and fisheries. Metal pollution due to industrial and agricultural activities represents an issue of growing concern for the Guayas River Basin and related mangroves in Ecuador. Fisheries and the related human consumption of mangrove crabs are in need of scientific support. In order to protect human health and aid river management, we analyzed several elements in the Guayas Estuary. Zn, Cu, Ni, Cr, As, Pb, Cd, and Hg accumulation were assessed in different compartments of the commercial red mangrove crab Ucides occidentalis (hepatopancreas, carapax, and white meat) and the environment (sediment, leaves, and water), sampled at fifteen sites over five stations. Consistent spatial distribution of metals in the Guayas estuary was found. Nickel levels in the sediment warn for ecological caution. The presence of As in the crabs generated potential concerns on the consumers' health, and a maximum intake of eight crabs per month for adults is advised. The research outcomes are of global importance for at least nine Sustainable Development Goals (SDGs). The results presented can support raising awareness about the ongoing contamination of food and their related ecosystems and the corresponding consequences for environmental and human health worldwide.

9.
Environ Sci Pollut Res Int ; 28(15): 19485-19496, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33394453

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) were measured in 32 surface sediment samples collected around three cities (Barcarena, Belém, and Santana) located on the coast of the Brazilian Amazon. The concentration of total PAHs ranged from lower than detection limit to 33,101 ng g-1 in a sample from Barcarena and was related to a large aluminum industrial complex and port activities. In Belém, which is the most populated area in the Amazon region, PAHs were probably derived from untreated sewage discharge and inputs from a large municipal landfill. Pyrogenic PAHs were predominant in both cities, with a smaller contribution of petrogenic PAHs. Low alkylated PAH levels may be associated with small boats and ship traffic. Santana had low total PAH concentrations, with a predominance of unusual alkylated PAHs, probably related to diagenetic transformations of organic matter in the sediment. In general, PAH concentrations in the samples were low and may reflect baseline levels for this Amazon estuarine system.


Subject(s)
Polycyclic Aromatic Hydrocarbons , Water Pollutants, Chemical , Brazil , Cities , Environmental Monitoring , Geologic Sediments , Polycyclic Aromatic Hydrocarbons/analysis , Water Pollutants, Chemical/analysis
10.
Braz. j. biol ; 80(2): 319-329, Apr.-June 2020. tab, graf
Article in English | LILACS | ID: biblio-1132379

ABSTRACT

Abstract This study intended to characterize the fee-fishing ponds located in Guarapiranga's sub-basin both in terms of structure and environmental conditions. The studied region was mapped and 15 out of 24 georeferenced fee-fishing ponds had their owners interviewed through semi-structured questionnaires. In addition to that, samples were collected from the seven fee-fishing ponds closest to the reservoir throughout a seasonal cycle divided in four sample collections carried out between November 2013 and August 2014, aiming at measuring the following variables in situ: water flow rates, pH, turbidity, electrical conductivity and dissolved oxygen concentration in affluents and effluents. Other samples were taken in order to assess total phosphorus (TP) and total nitrogen (TN) concentrations. Our results show a decrease in dissolved oxygen concentration along with an increase in TP and TN concentration in effluents, as compared to affluents. TP e TN concentrations exceeded the permitted values established by CONAMA 357/2005 - Class II resolution in all effluents at least during part of the year. High nutrient levels were observed in affluents, condition with which basins that have been affected by population growth are commonly met. It was verified, by interviewing the owners regarding venture management and by analyzing the collected samples, that there is significant correlation between the daily feeding and the TP and TN levels (p=0.021 and p=0.045, respectively), with the ponds where feeding is more intense having showed the highest nutrient levels in their effluents. The results highlight the importance of mitigation measures such as educating the owners on proper water management, the installation of pond aerators in conjunction with tanks the filters of which shall be composed of aquatic macrophytes in their effluents, as well as awareness campaigns aiming to reduce the usage of dough by fishermen in order to minimize detrimental impacts on Guarapiranga's sub-basin.


Resumo Este estudo objetivou caracterizar, em termos estruturais e ambientais pesqueiros localizados na sub-bacia da Guarapiranga. A região de estudo foi mapeada, e do total de 24 pesque-pague georreferenciados, 15 foram entrevistados com os proprietários através de questionários semi-estruturados e, nos sete pesque-pagues com tributários mais próximos da represa, foram coletadas amostras de água em um ciclo sazonal divididas em quatro coletas entre novembro de 2013 a agosto de 2014. Foram medidos in situ: vazão, pH, turbidez, condutividade elétrica e oxigênio dissolvido nos afluentes e efluentes, e também foram coletadas amostras de água para determinação da concentração de fósforo total (PT) e nitrogênio total (NT). Os resultados mostraram que há uma diminuição nas concentrações de oxigênio dissolvido e aumento nas concentrações de PT e NT nos efluentes em relação aos afluentes. Os efluentes apresentaram valores de PT e NT acima dos limites permitidos pela resolução CONAMA 357/2005 - Classe II, ao menos em um período do ano. Também foram identificados afluentes com cargas elevadas de nutrientes, característica de bacias impactadas pelo adensamento populacional. Através do questionário aplicado aos proprietários sobre o manejo dos empreendimentos e pelas análises de água verificou-se que houve correlação significativa entre o arraçoamento diário e as cargas de PT e de NT (p=0,021 e p=0,045, respectivamente), sendo que nos locais onde o arraçoamento foi mais intenso, a carga de nutrientes nos efluentes foi maior. Os resultados evidenciam a importância de medidas mitigadoras como orientações aos proprietários para o manejo adequado dos lagos, projetos de educação ambiental com os usuários para diminuir do uso de ceva para a captura dos peixes, além da instalação de aeradores artificiais nos lagos e tanques com filtros compostos de macrófitas aquáticas nos seus efluentes, minimizando os impactos na sub-bacia do Guarapiranga.


Subject(s)
Water Pollutants, Chemical , Rivers , Phosphorus , Water Quality , Ponds , Environmental Monitoring , Nitrogen
11.
Article in English | MEDLINE | ID: mdl-32384727

ABSTRACT

Studies have indicated that natural environments have the potential to improve the relationship between a stressful life and psychological well-being and physical health. Forest therapy has recently received widespread attention as a novel solution for stress recovery and health promotion. Bamboo is an important forest type in many countries, especially in East and Southeast Asia and in African countries. Bamboo is widespread throughout southwestern China. Empirical field research on the physiological effects of bamboo forest therapy is currently lacking. To explore the benefits of bamboo forest therapy on the physiological responses of university students, 120 university volunteers between the ages of 19 and 24 participated in this study (60 males and 60 females) and were randomly divided into four groups of equal size (15 males and 15 females in each). Four sites were selected for the experiment, including two natural bamboo forests (YA and YB), a bamboo forest park (DJY), and an urban environment (CS). During the testing period, all participants were asked to view the landscape for 15 min in the morning and then walk in the testing area for 15 min in the afternoon. Blood pressure (BP), heart rate (HR), and peripheral oxygen saturation (SpO2) were measured as the physiological indexes, and the semantic differential method (SDM) questionnaire was completed for the environmental satisfaction evaluation. The SDM for the subjective environmental evaluation differed significantly among the university students; they obtained a better environmental experience, in terms of sensory perception, atmosphere, climate, place, and space, in the bamboo forest sites. The three-day bamboo forest therapy session improved the physiological well-being of university students. First, the blood pressure and heart rate of the university students decreased, and the SpO2 increased, after the three-day viewing and walking activities of the three-day bamboo forest therapy session. The viewing activities had a more pronounced effect on decreased heart rate in university students. Additionally, three-day bamboo forest therapy had a positive impact on decreased systolic blood pressure and heart rate in the university students, and it was significantly decreased in females, while peripheral oxygen saturation (SpO2) remained relatively low. Finally, compared with the urban site (CS), the bamboo forest sites effectively improved the university students' physiological state of health, decreased their physical pressure, and stabilized their physiological indicators. These findings provide scientific evidence that a three-day bamboo forest therapy session can increase positive physiological responses. The potential for a longer-term effect on human physiological health requires further investigation.


Subject(s)
Forests , Horticultural Therapy , Students , Adult , Africa , China , Female , Humans , Male , Students/psychology , Universities , Young Adult
12.
Waste Manag Res ; 38(1): 44-58, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31438782

ABSTRACT

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.


Subject(s)
Industrial Waste , Waste Management , Hazardous Waste , Iran , Recycling
13.
Sci Total Environ ; 694: 133572, 2019 Dec 01.
Article in English | MEDLINE | ID: mdl-31756803

ABSTRACT

Due to global water scarcity, the use of reclaimed wastewater for crop irrigation is required; however, if the wastewater treatment is inadequate, it can be a source of environmental pollution. In order to improve wastewater reclamation, advanced oxidation processes (AOPs) have been tested. At full scale, ozonation is one such process that effectively removes micropollutants, despite its high-energy consumption. At pilot scale, other technologies such as the solar photo-Fenton process are being developed. This process is under consideration as a sustainable technology because it uses sunlight as a source of radiation. However, there is little information available on its environmental performance. In this work, we perform a comparative analysis between the ozonation and the photo-Fenton process as tertiary wastewater treatment processes used to reclaim wastewater for agricultural irrigation. We apply the Life Cycle Assessment (LCA) methodology for quantifying environmental impacts with ReCiPe and USEtox as life cycle impact assessment (LCIA) methods. The results show that both tertiary treatment options reduce water stress locally. Ozonation has a better overall environmental performance compared to the photo-Fenton process because the environmental impact of the required ozone is smaller than of the reactants involved in the solar photo-Fenton. Moreover, the first can be operated both day and night, and therefore needs no additional storage for collecting the nightly secondary effluent, and thus has lower infrastructure related impacts. Additionally, when the solar photo-Fenton process operates at an acidic pH, there are environmental drawbacks related to the pH adjustment, which consumes a large amount of acid thus liberating CO2. Finally, the environmental impacts associated with the discharge of micropollutants to soil through the use of reclaimed water are very small compared to the other impacts generated by the treatment. However, due to the current LCIA method limitations of micropollutant impact assessment, these are subject to major uncertainty.

14.
Waste Manag ; 69: 325-335, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28781157

ABSTRACT

This study aimed to compare the environmental performance of building construction waste management (CWM) systems in Hong Kong. Life cycle assessment (LCA) approach was applied to evaluate the performance of CWM systems holistically based on primary data collected from two real building construction sites and secondary data obtained from the literature. Different waste recovery rates were applied based on compositions and material flow to assess the influence on the environmental performance of CWM systems. The system boundary includes all stages of the life cycle of building construction waste (including transportation, sorting, public fill or landfill disposal, recovery and reuse, and transformation and valorization into secondary products). A substitutional LCA approach was applied for capturing the environmental gains due to the utilizations of recovered materials. The results showed that the CWM system by using off-site sorting and direct landfilling resulted in significant environmental impacts. However, a considerable net environmental benefit was observed through an on-site sorting system. For example, about 18-30kg CO2 eq. greenhouse gases (GHGs) emission were induced for managing 1 t of construction waste through off-site sorting and direct landfilling, whereas significant GHGs emission could be potentially avoided (considered as a credit -126 to -182kg CO2 eq.) for an on-site sorting system due to the higher recycling potential. Although the environmental benefits mainly depend on the waste compositions and their sortability, the analysis conducted in this study can serve as guidelines to design an effective and resource-efficient building CWM system.


Subject(s)
Environment , Solid Waste , Waste Management/methods , Construction Materials , Hong Kong , Recycling/methods
15.
Bioprocess Biosyst Eng ; 40(7): 1033-1048, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28409400

ABSTRACT

L-Lysine is an essential amino acid that can be produced by chemical processes from fossil raw materials, as well as by microbial fermentation, the latter being a more efficient and environmentally friendly procedure. In this work, the production process of L-lysine-HCl is studied using a systematic approach based on modeling and simulation, which supports decision making in the early stage of process design. The study considers two analysis stages: first, the dynamic analysis of the fermentation reactor, where the conversion of sugars from sugarcane molasses to L-lysine with a strain of Corynebacterium glutamicum is carried out. In this stage, the operation mode (either batch or fed batch) and operating conditions of the fermentation reactor are defined to reach the maximum technical criteria. Afterwards, the second analysis stage relates to the industrial production process of L-lysine-HCl, where the fermentation reactor, upstream processing, and downstream processing are included. In this stage, the influence of key parameters on the overall process performance is scrutinized through the evaluation of several technical, economic, and environmental criteria, to determine a profitable and sustainable design of the L-lysine production process. The main results show how the operating conditions, process design, and selection of evaluation criteria can influence in the conceptual design. The best plant design shows maximum product yield (0.31 g L-lysine/g glucose) and productivity (1.99 g/L/h), achieving 26.5% return on investment (ROI) with a payback period (PBP) of 3.8 years, decreasing water and energy consumption, and with a low potential environmental impact (PEI) index.


Subject(s)
Fermentation , Corynebacterium glutamicum , Lysine , Molasses , Saccharum
16.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467308

ABSTRACT

Abstract This study intended to characterize the fee-fishing ponds located in Guarapiranga's sub-basin both in terms of structure and environmental conditions. The studied region was mapped and 15 out of 24 georeferenced fee-fishing ponds had their owners interviewed through semi-structured questionnaires. In addition to that, samples were collected from the seven fee-fishing ponds closest to the reservoir throughout a seasonal cycle divided in four sample collections carried out between November 2013 and August 2014, aiming at measuring the following variables in situ: water flow rates, pH, turbidity, electrical conductivity and dissolved oxygen concentration in affluents and effluents. Other samples were taken in order to assess total phosphorus (TP) and total nitrogen (TN) concentrations. Our results show a decrease in dissolved oxygen concentration along with an increase in TP and TN concentration in effluents, as compared to affluents. TP e TN concentrations exceeded the permitted values established by CONAMA 357/2005 Class II resolution in all effluents at least during part of the year. High nutrient levels were observed in affluents, condition with which basins that have been affected by population growth are commonly met. It was verified, by interviewing the owners regarding venture management and by analyzing the collected samples, that there is significant correlation between the daily feeding and the TP and TN levels (p=0.021 and p=0.045, respectively), with the ponds where feeding is more intense having showed the highest nutrient levels in their effluents. The results highlight the importance of mitigation measures such as educating the owners on proper water management, the installation of pond aerators in conjunction with tanks the filters of which shall be composed of aquatic macrophytes in their effluents, as well as awareness campaigns aiming to reduce the usage of dough by fishermen in order to minimize detrimental impacts on Guarapirangas sub-basin.


Resumo Este estudo objetivou caracterizar, em termos estruturais e ambientais pesqueiros localizados na sub-bacia da Guarapiranga. A região de estudo foi mapeada, e do total de 24 pesque-pague georreferenciados, 15 foram entrevistados com os proprietários através de questionários semi-estruturados e, nos sete pesque-pagues com tributários mais próximos da represa, foram coletadas amostras de água em um ciclo sazonal divididas em quatro coletas entre novembro de 2013 a agosto de 2014. Foram medidos in situ: vazão, pH, turbidez, condutividade elétrica e oxigênio dissolvido nos afluentes e efluentes, e também foram coletadas amostras de água para determinação da concentração de fósforo total (PT) e nitrogênio total (NT). Os resultados mostraram que há uma diminuição nas concentrações de oxigênio dissolvido e aumento nas concentrações de PT e NT nos efluentes em relação aos afluentes. Os efluentes apresentaram valores de PT e NT acima dos limites permitidos pela resolução CONAMA 357/2005 Classe II, ao menos em um período do ano. Também foram identificados afluentes com cargas elevadas de nutrientes, característica de bacias impactadas pelo adensamento populacional. Através do questionário aplicado aos proprietários sobre o manejo dos empreendimentos e pelas análises de água verificou-se que houve correlação significativa entre o arraçoamento diário e as cargas de PT e de NT (p=0,021 e p=0,045, respectivamente), sendo que nos locais onde o arraçoamento foi mais intenso, a carga de nutrientes nos efluentes foi maior. Os resultados evidenciam a importância de medidas mitigadoras como orientações aos proprietários para o manejo adequado dos lagos, projetos de educação ambiental com os usuários para diminuir do uso de ceva para a captura dos peixes, além da instalação de aeradores artificiais nos lagos e tanques com filtros compostos de macrófitas aquáticas nos seus efluentes, minimizando os impactos na sub-bacia do Guarapiranga.

17.
Environ Sci Pollut Res Int ; 23(17): 17142-57, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27215982

ABSTRACT

PURPOSE: Dredging of sediments, a requirement for harbor maintenance, removes millions of tons of mineral wastes, contaminated at varying degrees with trace metals, from the water. In previous investigations, Cu and Zn have been identified as highly concentrated trace metals associated to sulfides, mineral phases sensitive to oxidation. In order to ensure their sustainable management, the solidification/stabilization (S/S) and/or the valorization of contaminated sediments as secondary raw materials is a way to be promoted. Indeed, their reuse as a substitute of sand in cemented mortar formulation would allow combining both treatment and valorization of such wastes. METHODS: In the present study, the environmental assessment of mortars formulated with raw and weathered marine sediments (in particular contaminated with Cu, Pb and Zn), compared to sand reference mortars, was conducted through two kinetic leaching tests: weathering cell tests (WCTs), in which mortars were crushed and leached twice a week, and a tank monolith leaching test (MLT), in which leaching was performed on monolithic mortars with increasing leachate renewal time. RESULTS: In both leaching tests, calcium and sulfur were released continuously from sediment mortars, showing the oxidation-neutralization processes of sulfides and carbonates. In the MLT, Cu was released by sediment mortars through diffusion, particularly by weathered mortars, at low concentrations during 60 days of the test duration. With the more aggressive WCT, Cu concentrations were higher at the beginning but became negligible after 7 days of testing. Pb was released through diffusion mechanisms until depletion in both tests, whereas Zn was particularly well immobilized in the cemented matrices. CONCLUSIONS: The S/S process applied using hydraulic binders proved to be efficient in the stabilization of Cu, Pb, and Zn highly presents in studied sediments, and further valorization in civilian engineering applications could be considered.


Subject(s)
Geologic Sediments/analysis , Oxidation-Reduction , Sulfides/analysis , Trace Elements/analysis
18.
Environ Monit Assess ; 188(5): 287, 2016 May.
Article in English | MEDLINE | ID: mdl-27075312

ABSTRACT

This study examines the benefits and risks associated with various types of wastewater recycled for vegetable garden irrigation and proposes the best water source in terms of its water quality impact on crop yields. The aim was to evaluate the usability of river, rain, gully pot, real grey and artificial grey waters to water crops. The objectives were to evaluate variables and boundary conditions influencing the growth of chillies (De Cayenne; Capsicum annuum (Linnaeus) Longum Group 'De Cayenne') both in the laboratory and in the greenhouse. A few irrigated chilli plants suffered from excess of some nutrients, which led to a relatively poor harvest. High levels of trace minerals and heavy metals were detected in river water, gully pot effluent and greywater. However, no significant differences in plant yields were observed, if compared with standards and other yields worldwide. The highest yields were associated with river water both in the laboratory and in the greenhouse. Plant productivity was unaffected by water quality due to the high manganese, potassium, cadmium and copper levels of the greywater. These results indicate the potential of river water and gully pot effluent as viable alternatives to potable water for irrigation in agriculture.


Subject(s)
Agricultural Irrigation/methods , Capsicum/growth & development , Environmental Monitoring , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/analysis , Agriculture/methods , Cadmium , Crops, Agricultural , Drinking Water , Fresh Water , Metals, Heavy/analysis , Rain/chemistry , Rivers/chemistry , Wastewater/chemistry
19.
Water Res ; 90: 128-140, 2016 Mar 01.
Article in English | MEDLINE | ID: mdl-26724447

ABSTRACT

A framework and an associated modeling tool to perform life cycle assessment (LCA) of urban water system, namely the WaLA model, has been recently developed. In this paper, the WaLA model is applied to a real case study: the urban water system of the Paris suburban area, in France. It aims to verify the capacity of the model to provide environmental insights to stakeholder's issues related to future trends influencing the system (e.g., evolution of water demand, increasing water scarcity) or policy responses (e.g., choices of water resources and technologies). This is achieved by evaluating a baseline scenario for 2012 and several forecasting scenarios for 2022 and 2050. The scenarios are designed through the modeling tool WaLA, which is implemented in Simulink/Matlab: it combines components representing the different technologies, users and resources of the UWS. The life cycle inventories of the technologies and users components include water quantity and quality changes, specific operation (electricity, chemicals) and infrastructures data (construction materials). The methods selected for the LCIA are midpoint ILCD, midpoint water deprivation impacts at the sub-river basin scale, and endpoint Impact 2002+. The results of the baseline scenario show that wastewater treatment plants have the highest impacts compared to drinking water production and distribution, as traditionally encountered in LCA of UWS. The results of the forecasting scenarios show important changes in water deprivation impacts due to water management choices or effects of climate change. They also enable to identify tradeoffs with other impact categories and to compare several scenarios. It suggests the capacity of the model to deliver information for decision making about future policies.


Subject(s)
Computer Simulation , Conservation of Natural Resources/methods , Waste Disposal, Fluid/methods , Water Purification/methods , Water Supply/methods , Cities , Climate Change , Drinking Water , Paris , Waste Disposal, Fluid/economics , Water Purification/economics , Water Resources , Water Supply/economics
20.
Eval Program Plann ; 55: 55-66, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26724715

ABSTRACT

Systematic triangulation may address common challenges in evaluation, such as the scarcity or unreliability of data, or the complexities of comparing and cross-checking evidence from diverse disciplines. Used to identify key evaluation findings, its application has proven to be effective in addressing the limitations encountered in country-level evaluation analysis conducted by the Independent Evaluation Office of the Global Environment Facility (GEF). These include the scarcity or unreliability of national statistics on environmental indicators and data series, especially in Least Developed Countries; challenges in evaluating the impacts of GEF projects; and inherent difficulties in defining the GEF portfolio of projects prior to the undertaking of the evaluation. In addition to responding to the need for further developing triangulation protocols, procedures and/or methodologies advocated by some authors, the approach offers a contribution to evaluation practice. This applies particularly to those evaluation units tasked with country-level evaluations in international organizations, facing similar constraints.


Subject(s)
Data Interpretation, Statistical , Environmental Health , Global Health , Humans , International Cooperation
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