A comparison of pretreatments on release of sugars from sweet sorghum bagasse for bioethanol production

Dilute acid pretreatment and steam pretreatment were evaluated for maximum sugars release and ethanol production from sweet sorghum bagasse (SSB). The fermentation potential of the condensate and hydrolysate obtained from steam pretreatment (10 kg/cm², 10 minutes) and dilute acid hydrolysis (1% (w/w) sulphuric acid, 25% substrate loading) respectively, was checked with Pichia stipitis NCIM 3497 and Debaryomyces hansenii sp. Ethanol production and yield using acid hydrolysate was higher with Debaryomyces hansenii sp. (28.4 g/L and 0.37 g/g respectively) as compared with Pichia stipitis NCIM 3497 (21.9 g/L and 0.29 g/g respectively).     

Contaminant mass flux and forensic assessment of polycyclic aromatic hydrocarbons: Tools to inform remediation decision making at a contaminated site in Canada

Polycyclic aromatic hydrocarbons (PAHs) and metal(loid) mass flux estimates and forensic assessment using PAH diagnostic ratios were used to inform remediation decision making at the Sydney Tar Ponds (STPs) and Coke Ovens cleanup project in eastern Canada. Environmental effects monitoring of surface marine sediments in Sydney Harbor indicated significantly higher PAH concentrations during the first year of remediation monitoring compared to baseline. This was equivalent to PAH loadings of ～2,000 kg over a 15‐month period. Increases in sediment PAH concentrations raised serious concerns for regulators, who requested cessation of remediation activities early in the $400 M (CAD) project. Historically, the STPs were reported as the primary source of PAH contamination in Sydney Harbor with estimated discharges of 300 to 800 kg/year between 1989 and 2001. Mass flux estimates of PAHs and metal(loid)s and PAH diagnostic ratios were used to evaluate if increases in PAH concentrations in marine sediments were the result of the STPs remediation activities. PAH mass flux estimates approximated that 17 to 97 kg/year were discharged from the STPs during three years of remediation and were corroborated by an independent PAH flux estimate of 119 kg in year 1. PAH fluxes to the Sydney Harbor were mostly surface water derived, with groundwater contributing negligible quantities (0.002–0.005 kg/year). Fluxes of metal(loid)s to harbor sediments were stable or declining across all years and were mirrored in sediment metal(loid) concentrations, which lacked temporal variation, unlike total PAH concentrations. Flux results were also corroborated using PAH diagnostic ratios, which found a common source of PAHs. Coal combustion was likely the principal source of PAHs and not migration from the STPs during remediation. Although short‐term residual sediment PAH increases during onset of remediation raised concerns for regulators, calls for premature cessation of remediation early in the project were unwarranted based on only one year of monitoring data. Mass flux estimates and forensic assessments using PAH diagnostic ratios proved useful tools to inform remediation decision making that helped environmental protection and reduced costs associated with lost cleanup time.     

Towards an international standard: The ISO/DIS 18504 standard on sustainable remediation

Sustainable remediation is the elimination and/or control of unacceptable risks in a safe and timely manner while optimizing the environmental, social, and economic value of the work. Forthcoming International Organization for Standardization (ISO) Standard on Sustainable Remediation will allow countries without the capacity to develop their own guidance to benefit from work done over the past decade by various groups around the world. The ISO standard has progressed through the committee draft (ISO/CD 18504) and draft international standard (ISO/DIS 18504) stages. The risk‐based approach to managing the legacy of historically contaminated soil and groundwater has been incorporated into policy, legislation, and practice around the world. It helps determine the need for remediation and the end point of such remediation. Remediation begins with an options appraisal that short lists strategies that could deliver the required reduction in risk. A remediation strategy comprises one or more remediation technologies that will deliver the safe and timely elimination and/or control of unacceptable risks. The ISO standard will help assessors identify the most sustainable among the shortlisted, valid alternative remediation strategies. Practitioners presenting case studies claiming to constitute sustainable remediation should now report how they have aligned their work with the new standard. Indicators are used to compare alternative remediation strategies. The simplest metric that allows a characteristic to act as an indicator should be chosen. Weightings indicators can become a contested exercise and should only be undertaken where there is a clear desire for it by stakeholders and a clear need for it in identifying a preferred strategy. The simplest means of ranking alternative remediation strategies should be adopted.     

Conversion of CCA-treated wood to ethanol: a method to reduce leaching of metals from disposed treated wood prior to disposal

The objective of this paper is to evaluate the feasibility of producing ethanol from CCA-treated wood that is highly leachable. Following the initial tests, CCA-treated wood was hydrolysed and fermented and the results showed not only that ethanol was produced during the fermentation process but that metals were taken up by the yeast. Toxicity characteristic leaching procedure tests of the hydrolysed wood leached less than 4 mg/L of As while minimal amounts of Cr and Cu remained in the hydrolysed wood which makes landfilling of hydrolysed wood acceptable and less hazardous. A slightly lower amount of ethanol from CCA-treated than untreated wood was produced (6 and 7 g/L, respectively). In general, it suggests that production of ethanol as a source of energy from a hazardous waste (CCA-treated wood) is feasible.     

Leaching behavior of some demolition wastes

Demolition wastes may be used in different civil engineering applications as road constructions, concrete, and embankments or landfill. Regardless its application, leaching tests of the waste should be carried out to assess concentrations of pollutants. Concrete, brick and mixture of concrete, bricks, tiles and ceramics wastes were subject to percolation test—CEN/TS 14405, and batch test—SR EN 12457. The leachates were analyzed with respect to concentration of inorganic elements—arsenic, barium, cadmium, chromium, copper, mercury, molybdenum, nickel, lead, selenium, zinc, fluoride, chloride and sulfate, and organic compounds (phenol index). The concentrations of elements in leachates were compared with the limit values of European regulation for the acceptance of inert wastes at landfills. Generally, the releases of inorganic species in leachates were below limits values. Some waste leachates obtained by percolation and batch test had high values for phenol index.     

Demonstrating Contaminant Degradation at an MGP Site With Metabolic Gas Flux and Radio Carbon Dating

Obtaining lines of evidence indicating that contamination in sediment environments is degrading and being transformed to less toxic forms is an important component of building support for a monitored natural recovery remedy for contaminated sediments. This project was a field demonstration of manufactured gas plant contaminant degradation in river sediments using metabolic gas flux and was performed in an urban area section of a river in northeastern Indiana. CO₂ sorbent traps were deployed to measure CO₂ flux from the river sediments. Sediment samples were collected and analyzed for polycyclic aromatic hydrocarbon (PAH) concentrations and for microbial community composition using molecular techniques. The results showed that the deployment was successful, measuring CO₂ flux at all sediment locations and demonstrating that microbial contaminant degrading activity was occurring in the sediments. Radio carbon dating showed a significant portion of the CO₂ being generated (approximately 19–27 percent) was the result of fossil fuel degradation. Molecular results showed that the microbial community consisted of phylotypes known to be associated with monocyclic aromatic and PAH degradation. ©2017 Wiley Periodicals, Inc.     

Comparing canopy leaf temperature of three Central European tree species based on simultaneous confidence bands for penalized splines

Temperature is an important physical factor that is known to strongly affect biodiversity as well as ecosystems and their functioning. However, research in this area is still relatively limited; this may also be attributed to the multitude of influencing factors and the complexity of the statistics involved. This study analyzes the differences between the surface temperature of three Central European broadleaf tree species. A better understanding of these differences may help to elucidate the role of microclimate in biodiversity. We consider a time series of high-resolution thermal images taken from a meteorological observation tower and calculate mean canopy leaf temperatures for beech, ash and maple (Fagus silvatica, Fraxinus excelsior and Acer pseudoplatanus). In a first step, comparable image areas are extracted from the thermal image sections of the crown of each tree species avoiding shadow areas, branches, etc. We used an automatic segmentation technique, the Otsu thresholding. Extracted canopy leaf temperature values were then processed and the resulting temperature profiles estimated by O’Sullivan penalized splines. For comparing the differences in canopy leaf temperature over time, we propose the construction of simultaneous confidence bands. The analyses show that there are significant—though small—differences in canopy surface temperature between the three tree species.     

2D brine sewage after impinging on a shallow sea free surface

We consider the problem of the vertically upwards disposal of heavy brine sewage from a two-dimensional diffuser in a lighter, homogeneous, motionless and shallow ambient sea. The rejected high salinity water of seawater desalination plants for urban and agricultural uses is such a case of a two dimensional fountain. The disposal of brine sewage produces a negative buoyant jet due to its initial momentum, which impinges on the free surface, spreads laterally on it and then sinks downwards, because of the negative buoyancy. Laboratory experiments and dimensional considerations are used in this paper in order to investigate the spreading behavior (width) of the vertical fountain which impinges on the free surface of the shallow ambient fluid. The experimental results have been used to derive an equation relating the width at the free surface with the initial parameters of the flow. In addition, the experimentally measured dilution of the heavier brine sewage on the recipient’s surface is compared with the dilution which was calculated by a numerical simulation of a well-known commercial software package, CORJET (a CORMIX sub model).     

The development of a method to determine the burden of climate change on different health outcomes at a local scale: a case study in Osaka Prefecture,Japan

Climate change impacts human health in a variety of ways. Variables including the climate-related risk factor, the health outcome and location all determine the nature and extent of the impact. The existence of different pathways and endpoints presents a problem for quantifying and comparing impacts. Disability-adjusted life year (DALY) provides a common scale, whereby the impact of climate change on both acute and chronic health outcomes can be compared. This study presents a methodology to calculate the impact of climate change on human health at a local scale, using cardiovascular disease (CVD) and meteorological disaster-related injuries (DRIs) in Osaka Prefecture, Japan, as applied case studies. An additional very fine scale assessment of CVD conducted at the neighbourhood level to demonstrate the importance of conducting risk assessments at a local level. The comparative results calculated the impact of climate change in 2050 to be 16.866 DALY/100,000 population for CVD and 0.645 DALY/100,000 for meteorological DRIs. The actual impact of climate change by 2050 on CVD is judged to be higher, although the relative risk was projected to be lower (1.006, compared to 1.263 for meteorological DRIs). The fine scale assessment revealed the variations in the projected impact of climate change on CVD for all administrative zones in Osaka Prefecture. The range of impacts varied from 0 to 114.29 DALY/100,000. The results demonstrate the applicability of using DALY to quantify the impact of climate change on different health outcomes, using a transferable methodology, and provide information that enables evidence-based prioritisation of climate change adaptation strategies at a local scale.     

Are we planning for sustainable disaster recovery? Evaluating recovery plans after the Wenchuan earthquake

This article examines local recovery plans that were created in response to the Wenchuan earthquake and then suggests ways that planners can better apply the concept of sustainability to the recovery process. We utilize a plan evaluation protocol to analyze 16 recovery plans in counties and towns that were severely affected by the earthquake. We also conducted semi-structured interviews with public officials and planners, with the qualitative data gleaned from these interviews being used to supplement the plan quality assessment. The results reveal that local recovery plans do not appear to have incorporated sufficiently the concepts of sustainability. We conclude the paper with the following recommendations: emphasizing sustainability as a policy priority during vision and goal development; developing solid databases and planning techniques; designing a diversified set of regulatory- and incentive-based policy tools suitable for local governments; enhancing social and institutional learning; and further integrating multi-level and interagency governmental units.