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This study aims to increase the scientific knowledge of the environmental impacts and externalities of two promising electrochemical-based techniques for large-scale stationary energy storage: lithium nickel cobalt manganese (NCM) and vanadium redox flow (VRF) batteries. The global warming potential (GWP) and cumulative energy demand (CED) for NCM and VRF batteries are 28 kg CO

Long-term impact tracking of urban water services is an important scientific basis for the sustainable development goals of future foreground systems. This study developed a dynamic life cycle assessment (DLCA) method that considers temporal variation and the resulting impacts to address the challenges of water treatment facilities based on the principles of life cycle assessment (LCA) and system dynamics (SD) models. The model was then demonstrated and validated for a water treatment facility in the Kinmen Islands, Taiwan. The SD model simulates long-term water demand in terms of growth in the domestic, agriculture, livestock, and manufacturing sectors, which provides specific inventory data for LCA calculations, with the aim of showing the impact change for future water treatment scenarios. The results showed that using imported water and reclaimed water reduced Kinmen's reliance on groundwater from 77 % to 43 % and reduced the vulnerability of urban water services. The environmental impact of water treatment plants is determined to be strongly related to the efficiency of water treatment. In the long run, wastewater treatment plants can reduce their impacts with an increase in efficiency (3.7 % impact reduction). Additionally, the development of reclaimed water technology and water savings can reduce the impact by 19 % and 13.7 %, respectively, compared to the implementation of desalination. In terms of energy policy, more profound energy savings were observed when energy saving and structure transformation were simultaneously carried out. On the other hand, desalination poses the most political risk and has energy-associated environmental impacts. The DLCA results from this study showcase the trend of impact variation over time and thus provide valuable insights for future policy-making in mapping out the benefits and priorities of policy promotion.

Microwave-assisted wet co-torrefaction of food sludge (FS) and six widely produced lignocellulose biowaste samples were performed for biochar production. Factors including the torrefaction temperature, reaction time, biowaste type, and blending ratio of sludge and biowaste were evaluated. Biochar produced from FS torrefied at 150 °C for 20 min exhibited the greatest enhancement of carbon content and higher heating value (HHV). Blending sludge with macadamia husk at a ratio of 25/75 (db%) under the same wet torrefaction condition further improved biochar quality, enhanced the fixed carbon content, caused the highest HHV (19.6 MJ/kg), and considerably decreased the ash content. Thermogravimetric analysis indicated that sludge and biowaste degradation followed first-order kinetics, and the resultant biochar exhibited improved thermal stability, combustion efficiency, and safety for biofuel applications because of the increase in the activation energy, frequency factor, and ignition and combustion temperatures. Biochar is an excellent coal substitute for power generation because of its enhanced energy efficiency (energy return on investment: 7.4) and environmental friendliness (45.2 % reduction in greenhouse gas emissions compared with using bituminous coal). Moreover, the protein and carbohydrate contents in the supernatant of FS co-torrefied with biowaste at different blending ratios increased by 1.8–9.0 and 0.8–3.4, respectively. These contents can be recycled back to the activated sludge unit as a nutrient source, rendering the process green and sustainable without any waste production.

This study aims to investigate the feasibility of using hyperspectral remote sensing technique by visible-near infrared spectroradiometer (VNIR, FieldSpec HandHeld 2) for rapid water monitoring of heavy metal, followed by comparison of different spectral preprocessing methods for the development of quantitative predictive model. The water samples evaluated in this study were prepared in our laboratory by dilution of stock solutions. Heavy metals of lead (Pb), zinc (Zn) and copper (Cu) in the range of concentration between 100 to 2000 mg/L were selected as the target samples in this study. The sensitive bands for the target metals were characterized in the range from 800 nm to 1075 nm, based on the reflectance spectral data. Spectral data for developing of the quantitative predictive model was first preprocessed with first derivative and logarithm transformation, followed by establishing of the prediction model using multivariate linear regression (MLR). It was observed that increase in the number of sensitive bands for the MLR can significantly improve the adjusted R2 for the model. The prediction model for Cu was found to have the highest adjusted R2 of 0.92 and least normalized root mean square error (NRMSE) of 0.065, while using the reflectance values of 7 sensitive bands. This result could be attributed to the blue color characteristic of the solution, whereas the others remain clear. Additionally, the first derivative transformation was determined as the best method for predicting Pb, whereas the logarithm transformation provided the best outcomes for predicting Cu and Zn.

Understanding the environmental impacts associated with water-related adaptation measures plays an important role in decision making, as some adaptation measures may not offer environmental benefits compared to traditional water systems. The water depletion index (WDI) is one water stress indicator used to estimate the impacts of water consumption. A dynamic WDI was constructed and employed in this study under climate change scenarios with weather and streamflow modeling. To demonstrate whether adaptation measures can reduce water depletion and to demonstrate how dynamic WDI affects assessment results, Taipei, a highly developed and populated city in Taiwan, was selected as a case study site. Decreased WDI from July to August and increased WDI from September to October were simulated under climate change. This approach implied that when measuring water consumption impacts, the WDI should be applied according to the corresponding time period. Additionally, by substituting 70% of potable water with rainwater in a four-story building, 17.9–159.3 m3 of the freshwater depletion risk might be reduced every month. As adaptation measures can be long-term strategies and long-lasting infrastructures, a dynamic WDI could provide policy makers with a method to accurately and effectively assess the impacts of applying water-related adaptation measures in response to climate change.

This present study documents the incidence of plastic digestion by shortfin mako shark (Isurus oxyrinchus), caught by the Taiwanese small-scale tuna longline fishery in the Northwest Pacific Ocean (between the northeast coast of Taiwan and Japan). In 20 stomachs of shortfin mako, nearly 10% of samples contained at least one piece of plastic debris. The ingested plastic debris was found in the forms of films (5.0 cm) and fragments (3.0 mm) and was identified as polypropylene (PP) based on its polymer characteristics. The results from the analysis provide evidence for the anthropogenic origin and potential intake pathway of direct engulfment of ingested plastics. Our results also confirmed the low incidence of plastic ingestion in shortfin mako, suggesting that pelagic marine species may be relatively less affected by plastic pollution. Future research efforts are thus needed to assess the long-term impact of plastic pollution on marine species.

The use of optical properties as key parameters has been widely used in water quality monitoring, which accelerates the advances of remote sensing in the field of environmental monitoring. Current analytical methods for determining heavy metals in water include flame atomic absorption spectrometry (FAAS), atomic adsorption spectrophotometry (AAS) and inductively coupled plasma (ICP) spectroscopy, which typically require use of chemicals for sample processing and pretreatment as well as high capital input for analysis. Therefore, this study aims at investigating the potential of using non-destructive approaches for rapid water monitoring of heavy metal from green chemistry perspective. The proposed non-destructive sensing techniques include X-ray fluorescence spectrometer (XRF) and visible-near infrared spectroradiometer (VNIR). The former is an elemental analyser specifically for elements with relatively high atomic number, and the latter measures the reflectance or transmittance from samples. Heavy metals of lead (Pb), zinc (Zn) and copper (Cu) were selected as the target water constitutes in the study. The results from the analysis were then be used for determining a correlation model through chemometric approaches. Our results demonstrated that both of the target metals could be analysed via the proposed analytical methods. Reasonable agreements between the measurements from XRF and ICP were observed, whereas moderate correlations were perceived for simple linear regression model using spectral information from VNIR. Results from this study are expected to provide useful information on rapid identification of metal-polluting sources.

Life cycle assessment (LCA) is a widely applied approach used to evaluate the environmental impacts of a product or service across its life cycle stages; however, the impacts of land use on ecosystem services are less addressed in most LCA studies. This study, therefore, aims to improve the LCA model by incorporating a new impact category of land use on ecosystem services at both midpoint and endpoint levels in the existing ReCiPe2016 impact assessment method. The impacts of land use in the LCA model included land occupation and land transformation. The soil quality-based indicator, soil organic carbon (SOC), was adopted to quantify the soil quality change in ecosystem services caused by land use. A site with contaminated soils was adopted to validate the proposed impact assessment approach and to compare the results of various remediation practices. Our results revealed that the characterization factors (CFs) varied with the type of land use intervention, with land occupation of settlements presenting the highest CFs and land occupation of forest presenting the most negative CFs and thus benefitting ecosystem services. These results were well reflected in the case study, while the type of land intervention was the key factor determining the impact level. The results suggested that long-term occupation, high contamination levels, and high material or energy use contributed to relatively higher impacts of land use on ecosystem services. The proposed approach enables the quantification of land use impacts on ecosystem services as expressed in monetary loss or benefit at the endpoint resource level. The impact assessment results indicated that the in situ bioremediation scenario contributed relatively higher impacts ($12,667 USD) than the excavation and thermal treatment scenario ($−37 USD). These monetary assessment results are informative and are expected to be used in the decision-making process towards achieving beneficial environmental outcomes.

Water sustainability is at the core of high-tech industries and reflects their efforts in terms of both economic and environmental benefits. In this study, a membrane capacitive deionization (MCDI)-based water treatment system was proposed for the production of ultrapure water and wastewater reclamation by deionization. The system achieved good deionization performance in single-pass mode for treating soft tap water (T1), hard tap water (T2), cooling tower blowdown (W1) and wastewater discharge from high-tech industries. Overall, the removal efficiencies for hardness and conductivity in the tested scenarios were at least 70.8% and 51.9%, respectively, and selectivity in ion removal was the highest in Na+ for T1, W1 and W2 and in Ca2+ for T2, as it was mainly affected by the initial molar concentration of major ions. The system also showed favorable characteristics of high charge efficiency and relatively low energy consumption. At an applied voltage of 1.6 V, the energy requirements vary from 0.014 to 0.68 kWh/m3 with a charge efficiency higher than 70%, while the optimal deionization time was estimated to be between 12 and 60 min considering the increase in both the mean deionization rate and mean deionization capacity for various feedwater scenarios. The levelized cost of water for the studied MCDI scenarios ranges from 0.35 to 0.53 $USD/m3, in which the capital and material costs generally outweigh the energy and other operational costs. The results of this study are expected to provide essential techno-economic recommendations for the practical adoption of the on-site MCDI process in industries.

Constructed wetlands are an ecological engineering technology that has been widely applied to treat anthropogenic wastewater. Until now, few studies have focused on soil carbon (C) in the constructed treatment wetlands in tropical regions. Therefore, this study provides insight into the changes in soil C composition of tropically constructed wetlands at different ages. Five constructed wetlands were investigated in northern Kaohsiung, Taiwan. Soil C was analyzed at three different depths using an acid-hydrolysable method. The results showed that soil TOC content was highest on the soil surface (0–2 cm) and decreased at greater soil depths (2–5 and 5–10 cm) in all the studied constructed wetlands. There was more soil acid-hydrolysable C in the older constructed wetlands than in the younger ones at all depths. On the contrary, the soil recalcitrant carbon (RP-C) did not vary much across the wetland soils. In addition, the RP-C to TOC ratios were higher in the younger than older constructed wetlands, implying that the soil bioavailable C sources for microbial growth increased with the wetland's age. As a result, the compositions of organotrophic microbes, such as methanogens (mcrA copies), appeared to increase with wetlands' ages (i.e., negatively correlated with RP-C/TOC), while the total microbial abundance (16S rDNA) and abundance of lithotrophic microbes, such as methanotrophs (pmoA copies), were not correlated with RP-C/TOC or AHPI-C/TOC ratios, based on the results of our canonical correspondence analysis. Furthermore, the constructed wetlands accumulated soil RP-C from 2.33 to 0.08 g C m−2 day−1 in the constructed wetlands 1 to 30 years old, respectively.

Water availability, resulting from either a lack of water or poor water quality is a key factor contributing to regional water stress. This study proposes a set of sector-wise characterization factors (CFs), namely consumptive and degradative water stresses, to assess the impact of water withdrawals with a life cycle assessment approach. These CFs consider water availability, water quality, and competition for water between domestic, agricultural and industrial sectors and ecosystem at the watershed level. CFs were applied to a case study of regional water management of industrial water withdrawals in Taiwan to show that both regional or seasonal decrease in water availability contributes to a high consumptive water stress, whereas water scarcity due to degraded water quality not meeting sector standards has little influence on increased degradative water stress. Degradative water stress was observed more in the agricultural sector than in the industrial sector, which implies that the agriculture sector may have water quality concerns. Reducing water intensity and alleviating regional scale water stresses of watersheds are suggested as approaches to decrease the impact of both consumptive and degradative water use. The results from this study may enable a more detailed sector-wise analysis of water stress and influence water resource management policies.

The importance of the interdependence between water and energy, also known as the water-energy nexus, is well recognized. The water-energy nexus is typically characterized in resource use efficienc ...

Sustainable resource management in small islands is very challenging. To address the challenges, four water and waste management strategies were proposed for a wastewater treatment plant in the Kinmen islands, Taiwan. Life cycle assessment was employed for evaluation of the environmental impacts and benefits (i.e., avoidance of impacts) associated with the resource management strategies at the plant. The results showed that the energy requirements (mainly electricity consumption) for water and sludge treatments in the wastewater treatment plant had the most remarkable impact as high as 98.6%. Significant environmental advantages could be achieved by reusing the reclaimed wastewater for agricultural applications (27.8% reduction in eutrophication potential), reusing the sludge for land applications (157% reduction in global warming potential), and generating energy from incineration of recycled sludge (impacts were neutralized). Impacts from addition of tertiary treatment for wastewater reclamation could be offset by preventing discharge of nutrients (i.e. N and P) into the environment. The reclamation also reduced the demand from groundwater pumping and associated impacts. Reuse of sludge for energy generation was more favorable than for land applications. This was mainly because eutrophication impact could not be avoided when the sludge was applied to soil (excess in nutrients), and, relatively higher reduction in global warming potential was observed for energy generation (−197 kg CO 2 eq/m 3 ) than for land applications (−18.8 kg CO 2 eq/m 3 ).

Multiple paternity has been demonstrated in a variety of sharks with different reproductive modes (i.e., viviparous, ovoviviparous, adelphophagy, oviparous), although the number of sires per litter varies considerably among species. To date, such analyses have focused mainly on coastal and nearshore shark species due to the difficulty in sampling oceanic sharks. In the present study, we observed multiple paternity in the oceanic shark Isurus oxyrinchus from seven polymorphic microsatellite loci and three litters collected from Nanfangao Fishing Port. Paternity tests showed that an average of 4.6 sires were assigned to each litter of I. oxyrinchus using COLONY software, and that the average number of sires dropped to 2.5 when using GERUD. These findings suggest that multiple paternity could be a common reproductive strategy used by the shortfin mako shark, and that this mating system should be integrated into a demographic model to make more accurate population projections and risk analyses in the future.

This study aims to investigate the feasibility of desalinating secondary effluent from a domestic wastewater treatment plant (DWTP) using membrane capacitive deionization (MCDI) for reclamation purposes. The desalination performance of a MCDI stack with 10 pairs of 20 cm × 20 cm activated carbon electrodes was evaluated in single-pass mode. As evidenced, the MCDI stack outperformed the capacitive deionization stack. The water quality characteristics of the inflows and product water were also analyzed. Our results revealed that MCDI can effectively remove undesired ions such as calcium and nitrate from the DWTP effluent for water reclamation. In particular, the solution conductivity of the product water was observed to be as low as 1.27 μS/cm. Removal of the ions was easily performed by the electrostatic field-assisted deionization process. The use of MCDI for low-salinity wastewater reclamation demonstrated favorable energy performance with a low volumetric energy input and a molar energy input of 0.12 kWh/m 3 and 0.03 kWh/mole, respectively; and the energy efficiency of this system is expected to be further improved by energy recovery or incorporation of energy-producing processes. These results are indicative of the benefits of using MCDI as part of the treatment processes for the reclamation of wastewater with low salinity.

Hierarchical porous carbon (HPC) has attracted increasing research interest for energy and environmental applications. HPC is conventionally fabricated by activated carbon, which potentially causes hidden environmental burdens. To overcome this issue, biochar, a promising renewable precursor, offers an attractive raw material substitute and has already been explored for the preparation of low-cost HPC. Recent studies have demonstrated that HPC exhibited great applications in capacitive energy storage, owning to its easily tuned physicochemical and electrochemical properties. Besides, biochar-based HPC with a three-dimensional (3D) interconnected controllable pore structure, high specific surface area (SSA), and pore volume (PV) can provide smaller resistance and shorter diffusion pathways for the transport of ions. Importantly, most recent research efforts have been made on the synthesis of biochar-based engineered hierarchical porous carbons (EHPCs) from biomass/biochar or developed from the HPC. A templating technique, heteroatom, and metal oxides doping have been applied to develop the biochar-based EHPC to improve 3D pore structure or/and expose abundant active sites and subsequently enhance the capacitive charge storage performance. In this review, recent advances in the applications of biochar-based HPC or EHPC for capacitive charge storage, e.g., capacitive deionization (CDI) and a supercapacitor (SC) are summarized and discussed. This review concludes with several perspectives to provide possible future research directions for the preparation and applications of biochar-based EHPC for capacitive charge storage. usc Refereed/Peer-reviewed

Assessment of life cycle environmental impacts and cumulative energy demand on a laboratory-scale capacitive deionizing (CDI) of brackish water was conducted in this study. The CDI system presented advantages of low energy demand at operation phase and low energy-related environmental impacts. With a measured electricity consumption for CDI operation at 1.44 MJ (0.4 kWh), the total cumulative energy demand for CDI system was estimated at approximately 23.9 MJ for production of 1 m3 of desalinated water. Results from the impact assessment indicated a global warming potential (GMP100) at 1.43 kg CO2 eq, which was mainly attributed to the major reduction in electricity consumption as compared to conventional desalination technologies. Moreover, material utilization and chemical use were shown to be most responsible for overall environmental impacts in the CDI system, particularly for the use of N,N-dimethylacetamide (solvent) and titanium (material for current collector). Use of such chemicals might produce derivatives that contributed to major impacts in ozone depletion and acidification potentials. This suggests that additional efforts in future studies of CDI system may be made to substitute or reduce the two to enhance overall environmental performance of the system.

Microwave-assisted wet torrefaction was adopted in this study for co-processing textile sludge (TS) and biowaste. Key operating parameters, including different temperatures (120–180 °C) and reaction times (10–30 min), for the torrefaction of legally recyclable TS (R-0906 in Taiwan) were evaluated. Furthermore, TS was blended with six widely produced types of lignocellulose biowaste at different blending ratios for improving the biochar quality and combustion characteristics. The results indicated that the optimal temperature and reaction time for TS torrefaction were 180 °C and 20 min, respectively, beyond which the fixed carbon content and higher heating values (HHVs) of biochar increased from 1.7% to 5.1% and 13.0–18.7 MJ/kg, respectively. However, biochar produced through the torrefaction of TS and macadamia husk with a blending ratio of 30/70 (db%) exhibited the highest fixed carbon content (29.8%) and HHV (19.7 MJ/kg) among the six tested lignocellulose biowaste samples with the atomic H/C and O/C ratios close to those of peat. The thermal stability, activation energy, frequency factor, and ignition and combustion temperatures of the biochar produced through microwave-assisted wet torrefaction co-processing were higher than those produced using raw TS or biowaste. The energy return on investment of the biochar system reached 10.9. Greenhouse gas emissions can be decreased by 57.5% if biochar is used as a bituminous coal substitute. Therefore, microwave-assisted wet torrefaction is a sustainable approach for mitigating the disposal problems of TS and lignocellulose biowaste as well as improving the energy performance and environmental friendliness of biochar-to-energy systems. Besides, the protein and carbohydrate contents in the supernatant of TS co-torrefied with biowaste at different blending ratios increased by 1.0–4.1 and 1.2–5.9 times, respectively. These contents can be recycled back to the activated sludge unit as a nutrient source. Overall, the microwave-assisted wet torrefaction process is green and economically beneficial.

Shell waste is a valuable natural material that is rich in calcium carbonate and can be directly used as limestone or as lime in a variety of applications. This study investigated the environmental impacts and tradeoffs associated with eggshell waste recycling treatment and reuse for land application, as well as performed a comparative analysis with oyster shell waste systems, using a life cycle assessment (LCA) approach. Our results confirmed that recycling treatment and reuse of eggshells may potentially generate more environmental impacts than conventional end-of-life disposal. It was estimated that the recycling and reuse of an average eggshell amount of 60 g accounted for nearly 0.187 kg CO2 eq of climate change impact and had other remarkable environmental impacts, such as marine ecotoxicity, freshwater ecotoxicity, freshwater eutrophication and human toxicity. This result could be mainly attributed to the involvement of energy-intensive conversion processes, such as calcination at 800 °C, in the treatment process. Similar trends in the impact results were obtained in the oyster shell system, although these were found at a larger extent. Furthermore, our results revealed that the processing capacity and energy sources were the two key influential factors affecting the overall impacts of shell waste processing and reuse. Thus, it is recommended that future efforts for mitigating the associated impacts should be focused on technological advancement and the implementation of environmentally friendly energy sources, with the goal of improving both economic and environmental sustainability.

This study explores the environmental and energy benefits of biomass residues, including crop residues and agricultural waste, for the production of renewable energy in the form of biochar as fuel, in order to offer recommendations for policy makers, by reviewing information regarding the key environmental issues associated with the implementation of the systems. The highest environmental benefits for biochar-to-fuel systems were most observed in reduction of global warming potentials (i.e., carbon abatement), particularly for those integrated with combined heat and power technology, or for those incorporating electricity offsets from biochar combustion and co-firing. But all of these practices come at the cost of hidden environmental burdens, such as elevations in eutrophication, acidification, carcinogens and ecotoxicity impacts, as a consequence from land use change, additional infrastructure requirement or additional fertilizer application connected to biochar production or post-treatment. Other notable challenges, including regional availability of biomass residues, improper management of the residues, limited economic incentives, low energy efficiency and synergies, as well as mistreating adverse impacts from indirect land use change, were discussed. This suggests the flexibility to adjust the biomass-biochar ratio to optimize desired energy yields, carbon abatement and environmental beneficial objectives. Comprehensive analysis of the trade-offs between energy yields, carbon abatement and other associated environmental impacts is therefore recommended for future studies. Future studies in this field are also advised to explore the solution and to develop methodologies capable of quantifying the impacts and other equally relevant trade-offs, to better reflect the changes in real-world trends for decision making.

Bioenergy products appear to be practical, effective, and environmentally sustainable renewable energy resources which simultaneously reduce fuel-associated environmental impacts and increase economic value of the products. The use of bioproducts may not always have a net positive environmental or economic attributes, therefore, an adequate sustainability evaluation tool for the products which incorporates life-cycle approach is generally desired. This paper presents an informative value analysis which couples concepts of life cycle energy efficiency and production cost ratios, for a feasible assessment of function value for bioenergy products. Bioenergy products that are selected for the value assessment in this study include biodiesel, bioethanol and biocharcoal. This study is divided into two parts: value factor development along with discussions on the results of value analysis for bioenergy products, and, a sensitivity analysis in determining influential factors for value factor estimations. The results showed that microalgae biodiesel and biochar had the lowest and the highest function values, respectively, among assessed bioenergy systems. This was mainly due to the significant difference in energy input in manufacturing design and production cost. Future improvements in bioenergy production can be anticipated for developing bioenergy products with high value factors which demonstrate high economic viability, environmental performance and social acceptability. This analysis can be of interest to bioenergy production planners for sustainable product development.

The objective of this study was to evaluate the effect of crude oil on water transport through mangroves roots in the presence and absence of dispersants. Water transport through the roots were evaluated experimentally using red mangrove root segments exposed to salt water contaminated with Louisiana crude oil for seven days in the presence and absence of Corexit 9500A (dispersant). Experimental observations were interpreted in view of the structural integrity and fouling phenomena observed on the epidermis and endodermis layers of the roots. The effects of oil on the radial water flux through the epidermis and endodermis were analyzed using a dual layer filtration model. Progression of fouling due to accumulation and penetration of the contaminants through the root layers were interpreted in relation to observed mangrove health (long and short term effects) reported in the literature.

Airborne molecular contaminants strongly affect the cleanroom air quality by severely degrading the image quality of semiconductor devices. This study aims to investigate the removal of N-methyl-2-pyrrolidone (NMP), an organic alkali compound that commonly appeared in cleanroom environment and used for photoresist stripping in integrated circuit fabrication processes, through adsorption by the citric acid (CA)-modified activated carbon chemical filters. Increase in CA concentration showed positive correlation to the quantity of CA coating but had negative influences on specific surface area. Immersion of carbon particles in solutions containing 3 M CA for 3 h yielded the most chemical modification according to the intensity of carbonyl and hydroxyl functional groups attached onto the carbon surface. NMP adsorption breakthrough studies demonstrated that NMP adsorption by virgin activated carbon was ineffective. Increase in the extent of CA modification resulted in greater adsorption capacity of NMP owing to increased quantity of carbonyl functional groups on its surface. Binary-component adsorption tests involving NMP and toluene vapours revealed that the CA-modified filters had little adsorption capability for toluene as compared to virgin filters. On the other hand, NMP was competitively favourable for adsorption on CA-modified filters, even when these filters were pre-saturated with toluene. The results of this research could be of value to cleanroom or building maintenance operators for technical and environmental improvements in future system design.

Multivariate statistical techniques of cluster analysis (CA) and discriminant analysis (DA) were applied in this study for the evaluation of water resource management strategies in high-tech industries, on the basis of the existing water use related data of 70 participating plants in Taiwan since 2011. The existing water use data were collected and transformed into detailed water balance charts, and the water use performance at individual plants was evaluated by three indices, namely the “processing water recovery rate”, the “plant water recovery rate”, and the “plant discharge rate”. Results from discriminant analysis showed that increase in the ratios of effluent recycled to pure water system (EPWR) and recycled to secondary water system (ESWR) had positive effects on achieving higher water use performance. On the other hand, process water consumption and ESWR were influential factors in discriminating samples with lower water use performance. The results also confirmed the finding from synergistic effect that improvement on both EPWR and ESWR contributed to the highest water use performance. Opportunities for water recycling in high-tech industries appears to be technically feasible, future efforts could usefully be undertaken to implement further investment on water-use efficiency and novel treatment techniques, and investigation on various reuse purposes.

In this study, we investigate the microscale structure of shark skin denticles at abdomen (A) and fin (F) locations, analyze the roughness and wetting properties related to their microstructures, and evaluate the effect of the surface properties on early bacterial attachment and biofilm formation. Microstructural analysis by scanning electron microscopy and confocal laser scanning microscopy confirmed the length (A: 165-180 μm vs. F: 145-165 μm), width (A: 86-100 μm vs. F: 64-70 μm), height (A: 10.5-13.5 μm vs. F: 6.2-8.8 μm), and density (A: 110-130 denticles/mm2vs. F: 80-130 denticles/mm2) of the denticles. The results showed that the roughness and hydrophobicity properties were affected with slight differences in the microscale architecture. The denticles with a larger width, higher ridge, and denser overlap provided a rougher and more hydrophobic surface. The microscale structure not only affected surface properties but also the biological attachment process. The microscale topography of shark skin slightly promoted bacterial attachment at an early stage, but prevented bacteria from developing biofilms. This systematic investigation provides insights into the effects of the surface topography of shark skin on its anti-fouling mechanism, which will enable the future development of various products related to human activity, such as healthcare products, underwater devices and applications, and water treatment applications.

Effectiveness of Corexit 9500A for dispersing Louisiana crude oil was evaluated in salt water solutions containing natural materials in relation to salinity and dispersant-to-oil ratio (DOR). Experimental results showed that both salinity and DOR had significant effects on dispersion of Louisiana crude oil in the presence of different natural materials. The natural materials added to the salt water solutions included sea sand (South Beach, Miami, Florida), red mangrove leaves (Rhizophora mangle), seaweed (Sargassum natans), and sea grass (Halodule wrightii). Dispersant effectiveness (amount of oil dispersed into the water) was reduced significantly with increasing salinity with the minimum effectiveness observed in the salinity range between 30 and 50 ppt in all aqueous samples containing natural materials. When significant amounts of floating oil were present, the partially submerged natural materials enhanced the transfer of oil into the water column, which improved the dispersion effectiveness. However, dispersant effectiveness was significantly reduced when the amount of floating oil was relatively small and could not be released back to the water column. Surface tension may not be an adequate parameter for monitoring the effectiveness of dispersants in salt water environment. When distilled water was used (i.e., zero salinity), surface tension was significantly reduced with increasing dispersant concentration. However, there was no clear trend in the surface tension of the salt water solutions (17–51 ppt) containing crude oil and natural materials with increasing dispersant concentration.

Integration of the food, energy, and water (FEW) nexus thinking is expected to enhance cross-sectoral discussion during the process of policy development. This process can be improved with comprehensive assessment tools to provide quantitative information regarding the interdependence of the FEW nexus. A comprehensive framework of the regional FEW nexus quantitative assessment was proposed in this study. Life cycle assessment (LCA) was the core method used to evaluate the FEW inter-linkages. Land use data which can further imply the resources consumption or requirement was introduced to estimate potential changes in the nexus in future time periods. In order to display the practicality of the FEW nexus approach, a user-friendly nexus platform, a GIS-based Regional Environmental Assessment Tool for Food-Energy-Water nexus (GREAT for FEW) ( http://greatforfew.enve.ntu.edu.tw/FEW/ ), was developed with a solid conceptual model, a database, and calculation methods. The usability of the tool was demonstrated using a Taiwanese case study. The results of the Taiwanese case showed that Scenario 1 (non-nuclear homeland policy) caused the lowest environmental impacts as compared to both Scenario 0 (baseline) and Scenario 2 (non-nuclear homeland policy with National Spatial Plan) due to better energy structures and maintenance of agricultural lands. These outcomes indicate that the selection of indicators does affect the results. Therefore, it is suggested that additional indicators should be designed based on the characteristics of the case study area and concerns of stakeholders.

The ultimate goals for the advancement of capacitive deionization (CDI) are high performance and low environmental impact. The aim of this study was to obtain comprehensive knowledge on the improvement of CDIs from environmental aspects. Life cycle assessment (LCA) was utilized to evaluate the environmental friendliness of the CDIs. Five lab-scale design schemes, including CDI, membrane capacitive deionization (MCDI) and scale-up MCDI stacks, were investigated in this study. A technical performance indicator of productivity (L/h/m2) was also employed to elucidate the efficiency of water production of the CDIs. The LCA results of the CDI stacks indicated that electricity consumption had a relatively lower overall impact (as low as 9.7%) compared to material or chemical usages (ranges from 52% to 89.8%). This result suggested that changing key materials or chemicals in improved stacks could decrease their associated impacts. Our results further pointed out the importance of the management of chemical use of N-methyl-2-pyrrolidone (NMP), the substitute for N, N-Dimethylacetamide (DMAC) in the basic CDI stack. The scale-up MCDI stacks exhibited the highest productivity of 3.62 L/h/m2, implying that CDI has the potential to be an efficient water technology. LCA was demonstrated to support future improvement decisions for CDI with favorable environmental performance.

During 2006-2007, Miami-Dade County, Florida, USA, provided incentives for low income and senior residents in single family homes for retrofitting with high efficiency fixtures. The participating residences were retrofitted with high-efficiency toilets, showerheads, and aerators. In 2012, a telephone survey was conducted to evaluate the satisfaction of the participants and the associated effects on water conservation practices. This study evaluates the attitudes and opinions of the participants relative to water use efficiency measures and the actual reduction in water consumption characteristics of the participating households. The participant characteristics were analyzed to identify correlations between the socio-demographic factors, program satisfaction and actual water savings. Approximately 65.5% of the survey respondents reported changes in their water use habits and 76.6% reported noticeable reduction in their water bills. The analyses showed that the satisfaction levels of the participants were closely correlated with the actual water savings. The results also showed that satisfaction level along with water saving potential (i.e., implementation of water efficiency devices) or change of water use habits has provided positive synergistic effect on actual water savings. The majority of the participants surveyed (81.3-89.1%) reported positive attitudes for water conservation incentive program and the benefits of the high efficiency fixtures.

Effects of multiple types of water use efficiency appliances on long term water savings and water use trend shifts were analyzed. The study group included senior and low income families in the urban areas of Miami-Dade County, Florida, USA. The participants in the study group experienced continuous and significant water savings within 3 years of the implementation of the water conservation incentives. Water savings were observed at approximately 200 l per household per day, which is about 31 % reduction in household water demand in comparison to the average residential water demand within the County. The water use profile of participants showed noticeable shifts over time in water demand frequency curves toward lower water consumption rates. The cost-saving analysis showed that adoption of multiple water efficiency appliances contributed to the highest annual monetary savings (i.e., high water savings and moderate product costs). Future conservation program planning efforts should take both water savings and product cost into account in order to achieve the greatest benefits.

The feasibility of a two-stage process involving carbon dioxide capturing and a photobioreaction (containing microalgae cells of Spirulina maxima) was investigated for the dual purpose of CO2 sequestration and wastewater remediation. The study systematically demonstrated the capability of CO2 removal through wet scrubbing using diluted wastewater as the scrubbing liquid and the potential of biomass growth in the CO2-enriched wastewater. The NaOH-alkalized wastewater provided a CO2 absorption capacity approximately equal to 0.5 g CO2 g–1 NaOH at 0.5 M, and the absorbed CO2 was effectively converted into usable bicarbonate to support the growth of S. maxima. The biomass productivity using the CO2-enriched wastewater (30% diluted) was 0.036 g L–1 d–1, which was in line with the productivity obtained from the controlled growth tests using NaHCO3 as the carbon source. Dilution of raw dairy (milk processing) wastewater was necessary as high chemical oxygen demand (COD) loading inhibited the growth of S. maxima....

Environmental impacts of energy and water demand and greenhouse gas emissions from three residential water-using appliances were analyzed using life cycle assessment (LCA) based approach in collaboration of economic input-output model. This study especially focused on indirect consumption and environmental impacts from end-use/demand phase of each appliance. Water-related activities such as water supply, water heating and wastewater treatment were included in the analysis. The results showed that environmental impacts from end-use/demand phase are most significant for the water system, particularly for the energy demand for water heating (73% for clothes washer and 93% for showerheads). Reducing water/hot water consumption during the end-use/demand phase is expected to improve the overall water-related energy burden and water use sustainability. In the analysis of optimal lifespan for appliances, the estimated values (8-21 years) using energy consumption balance approach were found to be lower than that using other methods (10-25 years). This implies that earlier replacement with efficiency models is encouraged to minimize the environmental impacts of the product.

In response to increasing water demand, Miami-Dade County, FL, USA implemented water conservation incentives for the residential customers. These incentives include rebates and unit exchange programs for showerheads, toilets and clothes washers. In this study, impacts of the water conservation incentives on water demand were analyzed. Water savings and water use trend shifts of the customers were evaluated during the first four years after the implementation of water conservation practices. About 6–14% reduction in water demand has been observed during the first and second years. The water savings continued during the third and fourth years at a lower percentage. Water savings for water use efficiency measures were about 28 (10.9%), 34.7 (13.3%) and 39.7 (14.5%) gallons per household per day for the showerhead, toilet, and clothes washer programs; respectively. Adoption of more than one type of water efficiency appliance contributed to additional saving in residential water use.

The Miami-Dade Water and Sewer Department (MDWASD) initiated a series of water conservation programs by implementing best management practices (BMPs) to respond the increasing water demand. The BMPs selected by MDWASD include high efficiency showerheads, toilets and clothes washers. The program has made significant impacts on water conservation in South Florida. The impacts are evinced by the water use trends as well as water consumption records of water conservation program participants who have made changes in their water use habits. Projections for water savings specific to different water conservation goals are presented in this study. The water conservation goals were defined as percentage savings per year, estimated water conservation quantities in daily water demand and targeted per capita water use to achieve desired water conservation goals. The appropriate water conservation rate is projected to be 1–2 million gallons per day (MGD) through 2030. With 2 MGD of water savings, the estimated per capita water use (GPCD) can be reduced from approximately 140–122 GPCD. Additional efforts are need reduce the water demand to US EPA's “water sense” conservation levels of 70 GPCD by 2030.

The Choshui river basin, the mother river in Taiwan, suffers from severe water shortage from extensive water use in irrigation as well as land subsidence from over-pumping of groundwater. To address these challenges, several water-related strategies and actions, including enhancement of water-use efficiency, development of alternative water sources, and improvement in effective water management, were proposed in this study to support sustainable water resource management in the watershed. Management of water resources in Taiwan is expected to confront not only freshwater resource but also energy source constraints. Multi-criteria decision analysis (MCDA), an approach for ranking overall performances of decision options, was then used to prioritize the water resource management strategies. The analysis considered economic (economic feasibility) and environmental (stability from the influence of climate change) criteria in the context of water&ndash, energy nexus (water supply/conservation potential and systemic energy efficiency). Our results indicated that, while economic feasibility was considered as the most important factor in implementation of the practices, improvement in groundwater pumping control and management was ranked as a high-priority water resource management action, followed by initiating water conservation programs for residential sector and reducing leakage rate for agricultural irrigation canals. The results from this study are expected to provide direction for future decision making in water resource management.

Microalgae-based bioremediation processes pose dual abilities of simultaneous CO2 fixation through photosynthesis and degradative effect on environmental pollutants. This study intends to investigate the tolerance and biodegradation capability of Spirulina maxima for removal of phenol. An assimilation study of the phenol-carbon was also conducted to elucidate if the phenol removal was dominated by physical adsorption on cell walls or through metabolic activities. S. maxima cells were found to be capable of growing on phenol up to a concentration of 400 mg l−1, and they had a highest specific growth rate at a phenol concentration of 50 mg l−1. The results suggested that the removal of phenol (as high as 97.5 %) was mainly due to biodegradation processes rather than a bioadsorption process. Moreover, it was evident that nearly 30 % of the 13C-labeled phenol content was discovered in the cellular fraction, indicating that the 13C-phenol-carbon was indeed assimilated to biomass followed by mineralize the carbon to CO2.

First order removal rates for 15 polyaromatic hydrocarbons (PAHs) in soil, sediments and mangrove leaves were compared in relation to the parameters used in fate transport analyses (i.e., octanol–water partition coefficient, organic carbon–water partition coefficient, solubility, diffusivity in water, HOMO–LUMO gap, molecular size, molecular aspect ratio). The quantitative structure activity relationships (QSAR) and quantitative structure property relationships (QSPR) showed that the rate of disappearance of PAHs is correlated with their diffusivities in water as well as molecular volumes in different media. Strong correlations for the rate of disappearance of PAHs in sediments could not be obtained in relation to most of the parameters evaluated. The analyses showed that the QSAR and QSPR correlations developed for removal rates of PAHs in soils would not be adequate for sediments and plant tissues.

The North County Regional Water Treatment Plant (NCRWTP) is one of two water treatment plants in the Collier County Public Water Supply System. The NCRWTP uses both nanofiltration (NF) and reverse osmosis (RO) treatment processes to produce drinking water for residential, commercial, industrial, and institutional uses. Groundwater is the sole source of raw water for drinking water production. The treatment plant is capable of treating 24.8 million gallons of raw water per day (MGD) for an overall potable water production rate of 20 MGD. Concentrate is pumped into a deep well injection system consisting of two Class I injection wells. Well No. 1 is 3,330 ft deep and Well No. 2 is 3,210 ft deep. The wells have been retrofitted with fiberglass injection tubing (corrosion resistant) and a cement-filled annulus (leakage prevention). Analysis of the monitoring wells and the injected concentrate stream include the following: pH, temperature, conductivity, bicarbonate, chloride, calcium, magnesium, iron, potassium, sulfate, total dissolved solids, total Kjeldahl nitrogen, sodium, fluoride, gross alpha and Radium 226/228. Monitoring results confirm that the injection wells have been well operated and no contamination of other aquifers or groundwater source has been discovered.