Stabilization of APC Residues from Waste Incineration with Ferrous Sulfate on a Semi-Industrial Scale

Abstract

A stabilization method for air pollution control (APC) residues from municipal solid waste incineration (MSWI) involving mixing of the residue with water and FeSO₄ has been demonstrated on a semi-industrial scale on three types of APC residues: a semidry (SD) APC residue, a fly ash (FA), and an FA mixed with sludge (FAS) from a wet flue gas cleaning system. The process was performed in batches of 165-175 kg residue. It generates a wastewater that is highly saline but has a low content of heavy metals such as Cd, Cr, and Pb. The stabilized and raw residues have been subject to a range of leaching tests: the batch leaching test, the pH-static leaching test, the availability test, and the column test. These tests showed that the stabilized residues have remarkably improved leaching properties, especially with respect to Pb but also with respect to Cd, Cu, and Zn. The release of Pb was reduced by a factor of 250-36,000.     

Air pollution modeling at road sides using the operational street pollution model--a case study in Hanoi, Vietnam

In many metropolitan areas, traffic is the main source of air pollution. The high concentrations of pollutants in streets have the potential to affect human health. Therefore, estimation of air pollution at the street level is required for health impact assessment. This task has been carried out in many developed countries by a combination of air quality measurements and modeling. This study focuses on how to apply a dispersion model to cities in the developing world, where model input data and data from air quality monitoring stations are limited or of varying quality. This research uses the operational street pollution model (OSPM) developed by the National Environmental Research Institute in Denmark for a case study in Hanoi, the capital of Vietnam. OSPM predictions from five streets were evaluated against air pollution measurements of nitrogen oxides (NO(x)), sulfur dioxide (SO2), carbon monoxide (CO), and benzene (BNZ) that were available from previous studies. Hourly measurements and passive sample measurements collected over 3-week periods were compared with model outputs, applying emission factors from previous studies. In addition, so-called "backward calculations" were performed to adapt the emission factors for Hanoi conditions. The average fleet emission factors estimated can be used for emission calculations at other streets in Hanoi and in other locations in Southeast Asia with similar vehicle types. This study also emphasizes the need to further eliminate uncertainties in input data for the street-scale air pollution modeling in Vietnam, namely by providing reliable emission factors and hourly air pollution measurements of high quality.     

Particle Mass Emission Rates from Current-Technology,Light-Duty Gasoline Vehicles

ABSTRACT

Now that the U.S. Environmental Protection Agency has promulgated new National Ambient Air Quality Standards for PM_2.5, work will begin on generating the data required to determine the sources of ambient PM_2.5 and the magnitude of their contributions to air pollution. This paper summarizes the results of an Environmental Research Consortium program, carried out under the auspices of the U.S. Council for Automotive Research. The program focused on particulate matter (PM) emissions from representative, current-technology, light-duty gasoline vehicles produced by DaimlerChrysler Corp., Ford Motor Co., and General Motors Corp. The vehicles, for the most part taken from the manufacturer's certification and durability fleets, were dynamometer-tested using the three-phase Federal Test Procedure in the companies' laboratories. The test fleet was made up of a mixture of both low-mileage (2K-35K miles) and high-mileage (60K-150K miles) cars, vans, sport utility vehicles, and light trucks. For each vehicle tested, PM emissions were accumulated over 4 cold-start tests, which were run on successive days. PM emission rates from the entire fleet (22 vehicles total) averaged less than 2 mg/mile. All 18 vehicles tested using California Phase 2 reformulated gasoline had PM emission rates less than 2 mg/ mile at both low and high mileages.     

Seasonal variations of hydroxylated and methoxylated brominated diphenyl ethers in blue mussels from the Baltic Sea

Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) found at high levels in the Baltic biota are mainly natural products, but can also be formed through metabolism or abiotic oxidation of polybrominated diphenyl ethers (PBDEs). The formation of OH-PBDEs is of concern since there is growing evidence of phenolic toxicity. This study investigates seasonal variations in levels of OH-PBDEs and MeO-PBDEs, focusing on an exposed species, the blue mussel (Mytilus edulis), sampled in the Baltic Sea in May, June, August and October of 2008. Both the OH-PBDE and MeO-PBDE levels in the mussels showed seasonal variations from May to October, the highest concentration of each congener appearing in June. The seasonal variation was more marked for OH-PBDEs than in MeO-PBDEs, but all congeners showed the same trends, except 6-MeO-BDE47 and 2′-MeO-BDE68, which did not significantly decline in concentrations after June. Biotic or abiotic debromination is suggested as a possible reason for the rapid decrease in methoxylated penta- and hexa-BDE concentrations observed in blue mussels from June to August, while the tetraBDE concentrations were stable. In addition, 1,3,7/1,3,8-tribrominated dibenzo-p-dioxins showed the same seasonal variation. The seasonal variations indicates natural formation and are unlikely to be due to transformation of anthropogenic precursors. The levels of PBDEs were fairly constant over time and considerably lower than those of the OH-PBDEs and MeO-PBDEs. The timing of the peaks in concentrations suggests that filamentous macro-algae may be important sources of these compounds found in the blue mussels from this Baltic Sea location.     

Monitoring plastic ingestion by the northern fulmar Fulmarus glacialis in the North Sea

The abundance of plastics in stomachs of northern fulmars from the North Sea is used in the OSPAR Ecological Quality Objective (EcoQO) for marine litter. The preliminary EcoQO defines acceptable ecological quality as the situation where no more than 10% of fulmars exceed a critical level of 0.1 g of plastic in the stomach. During 2003-2007, 95% of 1295 fulmars sampled in the North Sea had plastic in the stomach (on average 35 pieces weighing 0.31 g) and the critical level of 0.1 g of plastic was exceeded by 58% of birds, with regional variations ranging from 48 to 78%. Long term data for the Netherlands since the 1980s show a decrease of industrial, but an increase of user plastics, with shipping and fisheries as the main sources. The EcoQO is now also used as an indicator for Good Environmental Status in the European Marine Strategy Framework Directive.     

Movement and activity patterns of the European lobster, Homarus gammarus, revealed by electromagnetic telemetry

European lobsters, Homarus gammarus (L.), were tracked on an artificial reef in Poole Bay on the south coast of England using an electromagnetic telemetry system which monitored movements between reef units and recorded body movements (pitching and rolling) detected with a tilt switch incorporated into the transmitting tag. Several environmental variables (water temperature, light, hydrostatic pressure, current velocity and direction) were recorded simultaneously by the telemetry system, which was self-contained on the seabed. Movements between units of the artificial reef (excursions outside shelter) were predominantly nocturnal, peaking 1.5 to 3 h after sunset and returning to low levels shortly before dawn. A marked decline in the number of inter-reef unit movements from late summer to winter was related to decreasing water temperature rather than to daytime light level, wave height or tidal range. Activity indicated by the tilt switch was also greater at night, but declined gradually from a peak early in the night to a minimum at around midday, on average, implying a degree of activity within reef units during daylight. As with movements between reef units, activity declined seasonally with decreasing water temperature; in addition, the diel pattern of activity disappeared in winter. Received: 9 February 1998 / Accepted: 24 July 1998     

Population genetic analysis of Ensis directus unveils high genetic variation in the introduced range and reveals a new species from the NW Atlantic

We report current genetic variation of populations of the razor shell Ensis directus (Conrad 1843) (Mollusca: Bivalvia: Pharidae) in native (North American) and introduced (European) ranges using nuclear and mitochondrial sequence-based markers. We expected less variation within the introduced range, especially considering the frequent mass mortality events observed in Europe since the species was recorded for the first time in 1978. However, we found higher variation in Europe. The possible significance of temporal fluctuations of genetic variation, limited effect of random genetic drift, and multiple introductions are discussed. Interestingly, the multiple-introduction hypothesis contrasts with the gradual colonisation of European coastal waters but is supported by trained clustering analysis and by the intensity of transatlantic shipping. Genetic and morphometric evidence strongly supports that examined individuals from a supposed E. directus population from Newfoundland (Canada) belong to a separate species. This new Ensis is formally described here and named E. terranovensis n.sp.     

Mutual information in the Tangled Nature model

We consider the concept of mutual information in ecological networks, and use this idea to analyse the Tangled Nature model of co-evolution. We show that this measure of correlation has two distinct behaviours depending on how we define the network in question: if we consider only the network of viable species this measure increases, whereas for the whole system it decreases. It is suggested that these are complimentary behaviours that show how ecosystems can become both more stable and better adapted.     

How do Europeans want to live in 2040? Citizen visions and their consequences for European land use

The aspirations, motivations and choices of individual European citizens are a major driver of the future of global, European and local land use. However, until now no land use study has explicitly attempted to find out how the general public wants to live in the future. This paper forms a first attempt to survey European citizens to understand their desired future lives in relation to consequences for European land use. We used a crowdsourcing experiment to elicit visions from young Europeans about their lives in 2040. Participants completed a graphic novel around carefully selected questions, allowing them to create a story of their imagined future lives in pictures. The methodology worked well, and the sample seemed reasonably representative albeit skewed towards an educated population. In total, 1131 responses from 29 countries were received. Results show a strong desire for change, and for more sustainable lifestyles. There is desire for local and ecologically friendly food production, to eat less meat, to have access to green infrastructure and the ability to cycle to work. However, international travel remains popular, and the desire for extensive food production and owning detached houses with gardens will likely result in complex land use trade-offs. Future work could focus more specifically on quantifying these trade-offs and inform respondents about the consequences of their lifestyle choices. This was a first attempt to use crowdsourcing to understand citizen visions for their lives in the future, and our lessons learned will help future studies improve representativeness and increase responses.

     

How Certain Are Salmon Recovery Forecasts? A Watershed-scale Sensitivity Analysis

Complex relationships between landscape and aquatic habitat conditions and salmon (Oncorhynchus spp.) populations make science-based management decisions both difficult and essential. Due to a paucity of empirical data, models characterizing these relationships are often used to forecast future conditions. We evaluated uncertainties in a suite of models that predict possible future habitat conditions and fish responses in the Lewis River Basin, Washington, USA. We evaluated sensitivities of predictions to uncertainty in model parameters. Results were sensitive to 60% of model parameters but substantially so (|partial regression coefficients| >0.5) to <10%. We also estimated accuracy of several predictions using field surveys. Observations mostly fell within predicted ranges for riparian shade and fine-sediment deposition, but large woody debris estimates matched only half the time. We provide suggestions to modelers for improving model accountability, and describe how managers can incorporate prediction uncertainty into decision-making, thereby improving the odds of successful salmon habitat recovery.