Open AccessReview
Air Quality Impacts of Petroleum Refining and Petrochemical Industries
Environments 2017, 4(3), 66; doi:10.3390/environments4030066 -
Abstract
Though refineries and petrochemical industries meet society’s energy demands and produce a range of useful chemicals, they can also affect air quality. The World Health Organization (WHO) has identified polluted air as the single largest environmental risk, and hence it is necessary to
[...] Read more.
Though refineries and petrochemical industries meet society’s energy demands and produce a range of useful chemicals, they can also affect air quality. The World Health Organization (WHO) has identified polluted air as the single largest environmental risk, and hence it is necessary to strive for and maintain good air quality. To manage potential health impacts, it is important to implement proper air quality management by understanding the link between specific pollutant sources and resulting population exposures. These industries release pollutants such as Volatile Organic Compounds, greenhouse gases and particulate matter, from various parts of their operations. Air quality should be monitored and controlled more meticulously in developing nations where increased energy demands, industrialization and overpopulation has led to more emissions and lower air quality. This paper presents a review of findings and highlights from various studies on air quality impacts of petroleum refining and petrochemical plants in many regions in the world. Full article
Open AccessArticle
So Close Yet So Far Apart: Contrasting Climate Change Perceptions in Two “Neighboring” Coastal Communities on Aotearoa New Zealand’s Coromandel Peninsula
Environments 2017, 4(3), 65; doi:10.3390/environments4030065 -
Abstract
Coastal hazard risk, compounded by climate change, is escalating. Efforts to address this challenge are fraught and ‘success’ is elusive. We focus on this impasse and recommend ways to improve understanding, reduce risk and enable adaptation. Two Aotearoa New Zealand coastal communities, Mercury
[...] Read more.
Coastal hazard risk, compounded by climate change, is escalating. Efforts to address this challenge are fraught and ‘success’ is elusive. We focus on this impasse and recommend ways to improve understanding, reduce risk and enable adaptation. Two Aotearoa New Zealand coastal communities, Mercury Bay and Kennedy Bay, on the Coromandel Peninsula, serve as case studies. Ethnographic fieldwork underpins this analysis. Despite close proximity, local perceptions are ‘worlds apart’. Poor understanding of climate change, and preoccupation with everyday issues, is commonplace. Moreover, there are countervailing community narratives. In Kennedy Bay, which is undeveloped and Māori, climate change is not a manifest concern. Local narratives are rooted in Māori culture and under the shadow of colonization, which shapes contemporary perceptions, practices and prospects. In Mercury Bay, a rapidly developing resort town, seashore property owners demand protection works—ignoring sea-level rise and privileging short-term private interests. Despite laudable regulatory provisions, static responses to dynamic risks prevail and proactive adaptation is absent. Recommendations are made to improve understanding about local cultural-social-ecological characteristics, climate change and adaption. Enabling leadership and capability-building are needed to institutionalize proactive adaptation. Strengthening Māori self-determination (rangatiratanga) and guardianship (kaitiakitanga), and local democracy, are key to mobilizing and sustaining community-based adaptation governance. Full article
Figures

Figure 1

Open AccessArticle
Calcium Sulfoaluminate, Geopolymeric, and Cementitious Mortars for Structural Applications
Environments 2017, 4(3), 64; doi:10.3390/environments4030064 -
Abstract
This paper deals with the study of calcium sulfoaluminate (CSA) and geopolymeric (GEO) binders as alternatives to ordinary Portland cement (OPC) for the production of more environmentally-friendly construction materials. For this reason, three types of mortar with the same mechanical strength class (R3
[...] Read more.
This paper deals with the study of calcium sulfoaluminate (CSA) and geopolymeric (GEO) binders as alternatives to ordinary Portland cement (OPC) for the production of more environmentally-friendly construction materials. For this reason, three types of mortar with the same mechanical strength class (R3 ≥ 25 MPa, according to EN 1504-3) were tested and compared; they were based on CSA cement, an alkaline activated coal fly ash, and OPC. Firstly, binder pastes were prepared and their hydration was studied by means of X-ray diffraction (XRD) and differential thermal-thermogravimetric (DT-TG) analyses. Afterwards, mortars were compared in terms of workability, dynamic modulus of elasticity, adhesion to red clay bricks, free and restrained drying shrinkage, water vapor permeability, capillary water absorption, and resistance to sulfate attack. DT-TG and XRD analyses evidenced the main reactive phases of the investigated binders involved in the hydration reactions. Moreover, the sulfoaluminate mortar showed the smallest free shrinkage and the highest restrained shrinkage, mainly due to its high dynamic modulus of elasticity. The pore size distribution of geopolymeric mortar was responsible for the lowest capillary water absorption at short times and for the highest permeability to water vapor and the greatest resistance to sulfate attack. Full article
Figures

Figure 1a

Open AccessArticle
Collaborative Conservation of a Socio-Ecological Production Landscape through ICT Tools
Environments 2017, 4(3), 63; doi:10.3390/environments4030063 -
Abstract
Rural socio-ecological production landscape (SEPL) presents a mosaic combination of various use and spatial patterns. The rural SEPL claims conservation because it produces bundles of ecosystem services and well-being for people. However, due to the prevalent use of Information and Communication Technology (ICT)
[...] Read more.
Rural socio-ecological production landscape (SEPL) presents a mosaic combination of various use and spatial patterns. The rural SEPL claims conservation because it produces bundles of ecosystem services and well-being for people. However, due to the prevalent use of Information and Communication Technology (ICT) in recent years, we attempt to explore how the new ICT tool was employed to conserve the rural SEPL. This study targets four rural communities that the Balian River flows across in Sanzhi district, New Taipei city. These communities self-organized a river conservation patrol team and utilized LINE (an instant messaging software) group to manage the SEPL as well. We conducted mixed method research to collect their group conversation evidences including time, amount and content for basic quantitative analysis. Further, we adopted the qualitative in-depth interviews of key-informants to examine the characteristic of activities, the collaboration among communities and the benefits and issues during their action practices. The results show the ICT tools are indeed effective in assisting in social learning when conducting a cross-region of SEPL conservation activities. Full article
Figures

Figure 1

Open AccessArticle
A Methodology of Health Effects Estimation from Air Pollution in Large Asian Cities
Environments 2017, 4(3), 60; doi:10.3390/environments4030060 -
Abstract
The increase of health effects caused by air pollution seems to be a growing concern in Asian cities with increasing motorization. This paper discusses methods of estimating the health effects of air pollution in large Asian cities. Due to the absence of statistical
[...] Read more.
The increase of health effects caused by air pollution seems to be a growing concern in Asian cities with increasing motorization. This paper discusses methods of estimating the health effects of air pollution in large Asian cities. Due to the absence of statistical data in Asia, this paper carefully chooses the methodology using data of the Japanese compensation system. A basic idea of health effects will be captured from simple indicators, such as population and air quality, in a correlation model. This correlation model enables more estimation results of respiratory mortality caused by air pollution to be yielded than by using the relative model. The correlation model could be an alternative method to estimate mortality besides the relative risk model since the results of the correlation model are comparable with those of the relative model by city and by time series. The classification of respiratory diseases is not known from the statistical yearbooks in many countries. Estimation results could support policy decision-making with respect to public health in a cost-effective way. Full article
Figures

Figure 1

Open AccessArticle
Implementing REDD+ in a Conflict-Affected Country: A Case Study of the Democratic Republic of Congo
Environments 2017, 4(3), 61; doi:10.3390/environments4030061 -
Abstract
Due to their carbon sequestration potential, tropical forests are a focal point for mitigation of climate change through Reducing Emissions from Deforestation and Forest Degradation (REDD+). The Democratic Republic of Congo (DRC) contains the largest part of the Congo Basin, the second largest
[...] Read more.
Due to their carbon sequestration potential, tropical forests are a focal point for mitigation of climate change through Reducing Emissions from Deforestation and Forest Degradation (REDD+). The Democratic Republic of Congo (DRC) contains the largest part of the Congo Basin, the second largest rainforest in the world, and has become a main focus for REDD+ initiatives. However, DRC’s ongoing instability and conflict threatens the peace and security of local people, and outcomes of such global initiatives. Content analysis of 102 documents from four major REDD+ initiatives intervening in DRC, sought to understand how civil conflict is being integrated into the discourse on REDD+ and its implication for climate change mitigation. Results showed that discussion of how conflict and political instability might impact REDD+ outcomes was limited. Concrete approaches to address the reality of civil conflict were not evident. Governance reform was, however, an important emphasis of REDD+ in DRC. Since REDD+, peace-building and development initiatives are often funded by the same institutions, it is important to begin a dialogue as to how they can be more intentional in harmonizing approaches in conflict-affected, forest-rich countries like DRC. Finding synergies has the potential to improve overall outcomes for the global climate, the forest, and the lives of local people. Full article
Open AccessArticle
Environmental Risks and Uncertainty with Respect to the Utilization of Recycled Rolling Stocks
Environments 2017, 4(3), 62; doi:10.3390/environments4030062 -
Abstract
The railway industry is one of the most important sectors driving growth of regional economies worldwide. The industry has long dealt with both infrastructure and rolling stock. Many of these have reached the end of their lives. This paper highlights the rail policy
[...] Read more.
The railway industry is one of the most important sectors driving growth of regional economies worldwide. The industry has long dealt with both infrastructure and rolling stock. Many of these have reached the end of their lives. This paper highlights the rail policy for managing end-of-life rail vehicles. Initially when manufacturing rolling stock, different materials are considered in design and manufacture such as steel, aluminum, copper, polymers, glass. Based on the high economic and carbon costs of these materials, it is worthwhile to reuse or recycle them after their end-of-life cycle. In this study, three types of trains have been evaluated for comparison: freight, passenger and high speed. The material breakdowns from rail vehicles are evaluated for feasible applications in terms of reusing or recycling train components. We consider every material, taking into account the process of production, remaining life, advantages, disadvantages and potential threats derived from using such residual materials. The key aspects are risks and uncertainty associated with chemical and physical processes, corrosion and its varieties, oxidation, impact on the environment, release of toxicity, and pollution to the soil. These negative effects can indeed harm people, children, and assets in the vicinity. This paper therefore highlights the possibilities of recycling residual materials derived from rolling stock waste and any danger to the environment and the community, so that hazardous waste management can be put in place at the right time. Such insight will better shape sustainability policy for rolling stock procurement in the future. Full article
Figures

Figure 1

Open AccessArticle
Variations of Drinking Water Quality Influenced by Seasons and Household Interventions: A Case Study from Rural Maharashtra, India
Environments 2017, 4(3), 59; doi:10.3390/environments4030059 -
Abstract
The majority of people in rural villages in Maharashtra, India, have access to improved drinking water sources. Nevertheless, the water quality at the point of consumption often does not satisfy the drinking water standard. In this study, we assess changes in water quality
[...] Read more.
The majority of people in rural villages in Maharashtra, India, have access to improved drinking water sources. Nevertheless, the water quality at the point of consumption often does not satisfy the drinking water standard. In this study, we assess changes in water quality from its source to the point of consumption and explore the ties between water management practices and water quality. Water samples were collected at the water source and from 135 households’ drinking water storage tanks, and analyzed for fecal coliforms. In parallel, a survey was done to find out water treatment and storage interventions, sanitation and hygiene practices, and households’ perception of, and satisfaction with, drinking water quality. Our results show that even though 98% of the households in this study received their drinking water from an improved source, on average only 50% of sources, and even less during the monsoon, showed acceptable levels of fecal bacteria. Households’ engagement in treatment and storage interventions varied, but was considered crucial due to unreliable centralized chlorination at the village level. Further work is warranted to understand to what extent the different factors influence variations in water quality at the point of consumption and thus to determine what are the most effective interventions. Full article
Figures

Figure 1

Open AccessArticle
Modeling and Upscaling Plot-Scale Soil Erosion under Mediterranean Climate Variability
Environments 2017, 4(3), 58; doi:10.3390/environments4030058 -
Abstract
Soil erosion is an issue in the Mediterranean slopes. Erosion plots are useful to quantify erosion rates, but data are difficult to scale up to a slope level. Moreover, short observational frameworks are generally established, making it difficult to represent multi-year fluctuations. This
[...] Read more.
Soil erosion is an issue in the Mediterranean slopes. Erosion plots are useful to quantify erosion rates, but data are difficult to scale up to a slope level. Moreover, short observational frameworks are generally established, making it difficult to represent multi-year fluctuations. This paper deals with the potential of parsimonious modelling to upscale plot erosion (~23 m2) at Monte Pino Met European Research Observatory (South Italy) from 2001 to 2006. Under the assumption that the slope is fractal and contains plots, monthly gross soil erosion was modeled by lumping together the erosivity factor (runoff component), Normalized Difference Vegetation Index (vegetation cover factor), and the spatial scale dependence (slope length factor). This model was applied to reconstruct monthly gross soil erosion rates for the period of 1986–2006, for which hydrological inputs were available with sufficient detail. Pronounced interannual variations, with two distinct patterns, were observed: increasing rates of erosion were visible in 1995–2006 (peaking in November 1997, 50 Mg·ha−1·month−1), while in previous years only a few peaks slightly exceeded the average of the whole period (1 Mg·ha−1·month−1). Hydrological conditions indicate that important erosional processes have been triggered during low-frequency, short rainfall events occurring in spring–summer (e.g., May 2001, June 2003), or during longer, less intense events occurring in autumn–winter (e.g., November 1997) seasons. It is likely that increased precipitation amounts associated with more frequent convective storms created conditions for higher energy events triggering erosion. For the recent warm period, investigations at a higher than monthly resolution are required to better assess the seasonal changes of erosion rates and their relationship with soil conservation. Full article
Figures

Figure 1

Open AccessArticle
Biotrickling Filtration of Air Contaminated with 1-Butanol
Environments 2017, 4(3), 57; doi:10.3390/environments4030057 -
Abstract
The removal of high concentrations of 1-butanol in an air stream was evaluated with a biotrickling filter for potential application to an industrial off-gas. Experiments were conducted on a laboratory-scale system, packed with perlite, in a co-current downward mode with constant recycling of
[...] Read more.
The removal of high concentrations of 1-butanol in an air stream was evaluated with a biotrickling filter for potential application to an industrial off-gas. Experiments were conducted on a laboratory-scale system, packed with perlite, in a co-current downward mode with constant recycling of water. The performance was monitored for different inlet concentrations and empty bed residence times during a period of over 60 days of stable operation. A maximum elimination capacity (EC) of 100 g m−3 h−1 was achieved during periods in which the butanol concentration varied from 0.55 to 4.65 g m−3. The removal efficiency was stable and exceeded 80% for butanol concentrations in the range of 0.4 to 1.2 g m−3, corresponding to inlet mass loadings of up to approximately 100 g m−3 h−1. However, when the concentration exceeded 4 g m−3, removal efficiency rapidly dropped to 15% (EC of 22 g m−3 h−1), indicating an inhibition effect that was reversed by decreasing the inlet concentration. This biotrickling filter was able to deal with higher sustained butanol concentrations than have been previously reported, but might not be suitable for concentrations much in excess of 1.2 g m−3 or mass inlet loads in excess of 100 g m−3 h−1. Full article
Figures

Figure 1

Open AccessArticle
Geopolymerization Ability of Natural and Secondary Raw Materials by Solubility Test in Alkaline Media
Environments 2017, 4(3), 56; doi:10.3390/environments4030056 -
Abstract
The extent of the dissolution of aluminosilicate compounds is crucial, since the amount of Si and Al initially dissolved is essential for the following polycondensation and can strongly influence physical and mechanical performances of the final product. In order to set up a
[...] Read more.
The extent of the dissolution of aluminosilicate compounds is crucial, since the amount of Si and Al initially dissolved is essential for the following polycondensation and can strongly influence physical and mechanical performances of the final product. In order to set up a method to test the ability of a material to react in alkaline media, different aluminosilicate sources have been selected: a mineral resource (a zeolitized tuff), an industrial by product (silt from washing process of construction and demolition wastes), a heat treated clay sediment and a calcined clay (metakaolin). Two test methods, static and dynamic, have been applied to evaluate the attitude of a silicoaluminate precursor to give a geopolymerization reaction. In particular, a fixed amount of precursor was put into contact with a alkaline solution under continuous stirring or in static conditions at 60 °C for fixed times. The dynamic test method seems to be more suitable, since it is faster and requires lower amounts of reactants (solution). Moreover, the dynamic test provides a reactivity sequence (ordered from the more to the less reactive precursor) metakaolin > treated clay sediment > zeolitized tuff ≈ silt both for Si and Al release, which is coherent with the performances of geopolymers obtained by using the above precursors. Full article
Figures

Figure 1

Open AccessEditorial
Data-Modelling Applications in Water System Management
Environments 2017, 4(3), 55; doi:10.3390/environments4030055 -
Abstract
Water system management has a direct impact on natural and urban environments, covering a wide spectrum of field applications, ranging from watershed and groundwater management to natural and anthropic systems for water supply and wastewater harvesting. [...] Full article
Open AccessReview
Which Ballast Water Management System Will You Put Aboard? Remnant Anxieties: A Mini-Review
Environments 2017, 4(3), 54; doi:10.3390/environments4030054 -
Abstract
An accepted solution to the environmental problems related to a ship’s ballast water has been the adoption and proper utilization of approved onboard ballast water plans and management systems (BWMS). On 8 September 2017, the International Maritime Organization Ballast Water Management Convention comes
[...] Read more.
An accepted solution to the environmental problems related to a ship’s ballast water has been the adoption and proper utilization of approved onboard ballast water plans and management systems (BWMS). On 8 September 2017, the International Maritime Organization Ballast Water Management Convention comes into force, and under this Convention, ships engaged in international trade must have an approved BWMS aboard to discharge ballast water, reducing species transfer. In response to enormous global concern about this problem, the overwhelming majority of the BWMS, approved currently for use by International Maritime Organization (IMO) and United States Coast Guard, utilize two main technologies (electro-chlorination or ultraviolet irradiation) as their principle mode of disinfection, often used in combination with filtration. However, both technologies have been questioned regarding their practically, efficiency, and possible environmental impacts upon discharge. This review article aims to explore some questions about these two technologies, drawing attention to some current uncertainties associated with their use. Also, it draws attention to some technical obstacles and regulatory impediments related to the new development of green biocide technology, which largely has been ignored, despite its potential as a simpler, cleaner and effective technology. Full article
Open AccessShort Note
Commuters’ Personal Exposure to Ambient and Indoor Ozone in Athens, Greece
Environments 2017, 4(3), 53; doi:10.3390/environments4030053 -
Abstract
This pilot study aimed to monitor the residential/office indoor, outdoor, and personal levels of ozone for people living, working, and commuting in Athens, Greece. Participants (16 persons) of this study worked at the same place. Passive sampling analysis results did not indicate any
[...] Read more.
This pilot study aimed to monitor the residential/office indoor, outdoor, and personal levels of ozone for people living, working, and commuting in Athens, Greece. Participants (16 persons) of this study worked at the same place. Passive sampling analysis results did not indicate any limit exceedance (Directive 2008/50/EC: 120 µg/m3, World Health Organization (WHO) Air Quality Guidelines 2005: 100 µg/m3). The highest “house-outdoor” concentration was noticed for participants living in the north suburbs of Athens, confirming the photochemical ozone formation at the northern parts of the basin during southwestern prevailing winds. The residential indoor to outdoor ratio (I/O) was found to be significantly lower than unity, underlying the outdoor originality of the pollutant. The highest “office-indoor” concentration was observed in a ground-level building, characterized by the extensive use of photocopy machines and printers. Personal ozone levels were positively correlated only with indoor-office concentrations. A clear correlation of personal ozone levels to the time spent by the individuals during moving/staying outdoors was observed. On the other hand, no correlation was observed when focusing only on commuting time, due to the fact that transit time includes both on-foot and in-vehicle time periods, therefore activities associated with increased exposure levels, but also with pollutants removal by recirculating air filtering systems, respectively. Full article
Figures

Figure 1

Open AccessArticle
Life Cycle Assessment of a Three-Bedroom House in Saudi Arabia
Environments 2017, 4(3), 52; doi:10.3390/environments4030052 -
Abstract
The building sector is one of the crucial stakeholders in the global energy and environmental scenario. Life cycle assessment (LCA) is a tool widely used to evaluate the environmental performance of buildings, materials and activities. Saudi Arabia has a rapidly growing construction sector
[...] Read more.
The building sector is one of the crucial stakeholders in the global energy and environmental scenario. Life cycle assessment (LCA) is a tool widely used to evaluate the environmental performance of buildings, materials and activities. Saudi Arabia has a rapidly growing construction sector with over $1 Trillion of ongoing projects. The housing sector, annually needing over 2.32 million new residential units in coming years, is yet to entertain environmental performance of buildings in its list of priorities. The present work undertakes a LCA study of a three-bedroom modern villa located in Dhahran. Providing the structural details of the villa, an account of the 18 main construction materials in terms of quantity and application has been produced. Embodied energy of these materials has been estimated adopting ‘cradle-to-gate’ approach. Environmental impacts of the materials have been modeled with the help of SimaPro software. The results suggest that concrete accounts for more than 43% of the total embodied energy of the house and is also the predominant material in terms of the overall environmental impacts. Steel is the second most prominent material both in terms of quantity and embodied energy. Full article
Figures

Figure 1

Open AccessArticle
Hydrological Consequences of Timber Harvesting in Landscape Zones of Siberia
Environments 2017, 4(3), 51; doi:10.3390/environments4030051 -
Abstract
Despite a large number of publications covering various aspects of the influence of climatic factors on runoff, this direction in hydrological research acquires a new meaning in connection with global climate change and the increase in anthropogenic press on river systems. The authors
[...] Read more.
Despite a large number of publications covering various aspects of the influence of climatic factors on runoff, this direction in hydrological research acquires a new meaning in connection with global climate change and the increase in anthropogenic press on river systems. The authors of this work focused on the impact of anthropogenic factors on river runoff. Many rivers of Siberian taiga drain areas have experienced a dramatic land-cover change, with a decrease in overall forest area and a relative increase in deciduous trees. Land cover change in forest catchments impact water balance and accordingly, river flow. The study areas, the West Sayan and Northern Angara regions located in Central Siberia, are now a mosaic of forest regeneration sites including both post-human and post-fire regeneration patterns. Data of our own hydrological experiments conducted on clear cuts of different ages and reference materials for regular hydrological observations were analyzed. Dynamics of river flow under influence of timber harvesting were studied for 11 river basins in different landscape zones of Siberia. The studies showed that, in Siberia, forest cover changes lead to either reduction of, or increase in water yield depending on forest structure and climate. Dynamics of river flow after forest logging differ for continental and humid climates. Where precipitation is excessive, water yield increases twice that of control plots during the first several post-cutting years, due to reduction of transpiring phytomass. It takes 30–40 years and sometimes even over 50 years, depending on forest succession trajectories, for water yield to recover to the pre-cutting level. In an extremely continental climate, extensive forest cutting results in decreasing water yield during the first post-clearcutting years, because wind activity increases and enhances snow evaporation on vast clear cuts. Water yield exhibited an average annual decrease of 0.5–1.0 mm during the first two decades after cutting, i.e., until when clear cuts began to regenerate. With further development of forest vegetation, water yield increased by 1.5–3 mm annually. Obtained results show that at the regional level in conditions of anthropogenic press on the forests at the catchments of medium and small rivers, the climatic trends are offset by the felling and subsequent reforestation dynamics at clear cuts. Full article
Figures

Figure 1

Open AccessOpinion
Blockchain: The Evolutionary Next Step for ICT E-Agriculture
Environments 2017, 4(3), 50; doi:10.3390/environments4030050 -
Abstract
Blockchain technology, while still challenged with key limitations, is a transformative Information and Communications Technology (ICT) that has changed our notion of trust. Improved efficiencies for agricultural sustainable development has been demonstrated when ICT-enabled farms have access to knowledge banks and other digital
[...] Read more.
Blockchain technology, while still challenged with key limitations, is a transformative Information and Communications Technology (ICT) that has changed our notion of trust. Improved efficiencies for agricultural sustainable development has been demonstrated when ICT-enabled farms have access to knowledge banks and other digital resources. UN FAO-recommended ICT e-agricultural infrastructure components are a confluence of ICT and blockchain technology requirements. When ICT e-agricultural systems with blockchain infrastructure are immutable and distributed ledger systems for record management, baseline agricultural environmental data integrity is safeguarded for those who participate in transparent data management. This paper reviewed blockchain-based concepts associated with ICT-based technology. Moreover, a model ICT e-agriculture system with a blockchain infrastructure is proposed for use at the local and regional scale. To determine context specific technical and social requirements of blockchain technology for ICT e-agriculture systems, an evaluation tool is presented. The proposed system and tool can be evaluated and applied to further developments of e-agriculture systems. Full article
Figures

Open AccessArticle
Effects of Physico-Chemical Post-Treatments on the Semi-Continuous Anaerobic Digestion of Sewage Sludge
Environments 2017, 4(3), 49; doi:10.3390/environments4030049 -
Abstract
Sludge production in wastewater treatment plants is increasing worldwide due to the increasing population. This work investigated the effects of ultrasonic (ULS), ultrasonic-ozone (ULS-Ozone) and ultrasonic + alkaline (ULS+ALK) post-treatments on the anaerobic digestion of sewage sludge in semi-continuous anaerobic reactors. Three conditions
[...] Read more.
Sludge production in wastewater treatment plants is increasing worldwide due to the increasing population. This work investigated the effects of ultrasonic (ULS), ultrasonic-ozone (ULS-Ozone) and ultrasonic + alkaline (ULS+ALK) post-treatments on the anaerobic digestion of sewage sludge in semi-continuous anaerobic reactors. Three conditions were tested with different hydraulic retention times (HRT, 10 or 20 days) and sludge recycle ratios (R = QR/Qin (%): 50 or 100%). Biogas yield increased by 17.8% when ULS+ALK post-treatment was applied to the effluent of a reactor operating at 20 days HRT and at a 100% recycle ratio. Operation at 10 days HRT also improved the biogas yield (277 mL CH4/g VSadded (VS: volatile solids) versus 249 mL CH4/g VSadded in the control). The tested post-treatment methods showed 4–7% decrease in effluent VS. The post-treatment resulted in a decrease in the cellular ATP (Adenosine tri-phosphate) concentration indicating stress imposed on microorganisms in the reactor. Nevertheless, this did not prevent higher biogas production. Based on the results, the post-treatment of digested sludge or treating the sludge between two digesters is an interesting alternative to pre-treatments. Full article
Figures

Figure 1

Open AccessArticle
Adsorption of Extracellular Polymeric Substances Derived from S. cerevisiae to Ceria Nanoparticles and the Effects on Their Colloidal Stability
Environments 2017, 4(3), 48; doi:10.3390/environments4030048 -
Abstract
In order to understand the adsorption preferences of extracellular polymeric substances (EPS) components derived from fungus Saccharomyces cerevisiae on sparingly soluble CeO2 nanoparticles (CeNPs), the adsorption experiments of the EPS including organic matter with low molecular weight have been performed at pH
[...] Read more.
In order to understand the adsorption preferences of extracellular polymeric substances (EPS) components derived from fungus Saccharomyces cerevisiae on sparingly soluble CeO2 nanoparticles (CeNPs), the adsorption experiments of the EPS including organic matter with low molecular weight have been performed at pH 6.0 at room temperature (25 ± 1 °C). The subsequent effects of the coating on the dispersibility of CeNPs was systematically measured as a function of time and ionic strength ranging from 1 to 1000 mmol L−1. Among the EPS and other components, orthophosphate and saccharides preferentially adsorb onto CeNPs, and proteins are the only major N-compounds adsorbing onto the CeNP surfaces. Adsorption of orthophosphate resulted in a dramatic decrease in ζ potential to −40 mV at pH > 5, whereas the EPS adsorption suppressed the deviation of ζ potential within a narrow range (−20–+20 mV) at pHs ranging from 3 to 11. Critical aggregation concentrations (CAC) of an electrolyte (NaCl), inorganic orthophosphate, and EPS solutions are 0.01, 0.14, and 0.25 mol L−1, respectively, indicating that the EPS adsorption suppresses aggregation of CeNPs by the electrostatic repulsive forces derived from the adsorbed orthophosphate and the steric barrier formed by organic matter on the nanoparticle surfaces. Therefore, the EPS derived from fungus S. cerevisiae can potentially enhance colloidal dispersibility of CeNPs at circumneutral pH. Full article
Figures

Figure 1

Open AccessArticle
Development of ICT for Leaching Monitoring in Taiwan Agricultural LTER Stations
Environments 2017, 4(3), 47; doi:10.3390/environments4030047 -
Abstract
In order to study the groundwater subsidy from different cropping systems, leaching monitoring in Taiwan started in 2008 and implemented agricultural long-term ecological research (LTER) stations. Initially, leaching data was received by lysimeters, and then collected manually by laborers in the field twice
[...] Read more.
In order to study the groundwater subsidy from different cropping systems, leaching monitoring in Taiwan started in 2008 and implemented agricultural long-term ecological research (LTER) stations. Initially, leaching data was received by lysimeters, and then collected manually by laborers in the field twice per month. The cost of data collection and transmission is high, real-time monitoring is not possible, and maintenance of instruments is inefficient. In this study, the goal is to develop a data transmission path. ICT (Information and Communication Technology) with different data transmission schemes was applied to improve the efficiency and immediacy of data transfer from the field to the databases in labs. Between 2010 and 2017, four versions of ICT have been developed and applied in LTER stations. WiFi, 2.5G (General Packet Radio Service, GPRS), 3G/4G network transmission, and Arduino cores are applied in different ICT versions. The first version of data transmission used data loggers, developed by the original factory, with a lower cost of renovation of instruments. However, complicated transmission paths, diverse instruments, poor weather resistance, and lack of wireless functionality are the limitations of the first version. Those limitations had been overcome by the second and third versions by using 2.5G (GPRS) and 3G/4G network transmission, respectively. Nevertheless, these versions are limited to the processes of data compression and encryption transmission which were developed by the system vendors. In addition, data can only be collected through the webpage provided by the vendors, instead of being received directly from the database using SQL (Structured Query Language). This is inappropriate for advanced data treatment, organization, and analysis. Finally, the fourth version of data transmission has been developed using Arduino. This system allows redesigning of the data loggers and transmission instrument with more feasibility and flexibility. Radio Frequency (Radio frequency, RF) has been imported into the transmission path to receive data from diverse instruments with fewer data loggers. In conclusion, ICT technological advancement with its advantages of reasonable cost and high flexibility and feasibility, Arduino and other open source operation systems can be used to develop the data loggers and related instruments to meet the needs of users. Therefore, ICT is the most appropriate strategy to develop the long-term monitoring system in the field and to apply to other environment monitoring systems. Full article
Figures

Figure 1