Report: waste refinery in the municipality of Bor?s.

This paper briefly describes waste treatment trends in Sweden and describes an example of state-of-the-art treatment in a local integrated waste treatment system (Bor?s). The focus is on treatment of household waste, to illustrate what can be done to establish a sustainable waste treatment system with high recovery of materials and energy. The various processes have resulted in a low amount of landfilled household waste, and high proportions of recovered energy and materials. Heat, electricity, vehicle fuel and fertilizers, metals and construction materials are recovered from the local waste in Bor?s, with less than 4% of domestic waste being sent to landfill.     

An Experimental Study of Hopper Evacuation Effects on Multitube Cyclone Performance

An experimental multitube cyclone facility was constructed and experiments conducted to investigate the influence of hopper evacuation on multitube cyclone performance. The effects of the amount of hopper evacuation and the location of hopper evacuation on individual cyclone tube velocities and particle collection efficiency were determined. Cyclone tube velocities increased with increasing hopper evacuation although hopper evacuation location had little effect on the velocities. Particle collection efficiencies were increased from 89.5 percent to approximately 95 percent with 14 percent hopper evacuation from a location near the center of the hopper. Other hopper evacuation locations were not as effective in increasing collection efficiency. These results suggest that, while the increased velocity in the cyclone tubes is an important effect in the improvement of multitube cyclone performance with hopper evacuation, other factors such as redistribution of gas flow within the hopper are also important.     

Determination of sterols, estrogens and inorganic ions in waste water and size-segregated aerosol particles emitted from waste water treatment

Concentrations of steroids and inorganic ions were measured in waste water of an aerated sand trap as well as in aerosol particles emitted from this tank at the waste water treatment plant (WWTP) of Bayreuth, Germany, in January and February 2003. The investigations comprised seven sterols, two estrogens, and several inorganic ions. Since an appropriate method for the determination of sterols in waste water was not available, a new method based on solid phase extraction was developed. The concentrations of the sterols coprostanol and cholesterol amounted to 30-180 microg l(-1) in waste water and to 400-5000 pg m(-3) in aerosol particles. All other sterols were present in markedly lower concentrations. The mean concentrations of the two estrogens estrone and 17beta-estradiol were about 165 pg m(-3) in aerosol particles. The steroid concentrations in both waste water and aerosol particles varied greatly over time, however with the exception of coprostanol, no clear correlation was detected between concentrations in waste water and aerosol particles.     

Improved understanding of hyperaccumulation yields commercial phytoextraction and phytomining technologies

This paper reviews progress in phytoextraction of soil elements and illustrates the key role of hyperaccumulator plant species in useful phytoextraction technologies. Much research has focused on elements which are not practically phytoextracted (Pb); on addition of chelating agents which cause unacceptable contaminant leaching and are cost prohibitive; and on plant species which offer no useful phytoextraction capability (e.g., Brassica juncea Czern). Nickel phytoextraction by Alyssum hyperaccumulator species, which have been developed into a commercial phytomining technology, is discussed in more detail. Nickel is ultimately accumulated in vacuoles of leaf epidermal cells which prevents metal toxicity and provides defense against some insect predators and plant diseases. Constitutive up-regulation of trans-membrane element transporters appears to be the key process that allows these plants to achieve hyperaccumulation. Cadmium phytoextraction is needed for rice soils contaminated by mine wastes and smelter emissions with 100-fold more soil Zn than Cd. Although many plant species can accumulate high levels of Cd in the absence of Zn, when Cd/Zn>100, only Thlaspi caerulescens from southern France has demonstrated the ability to phytoextract useful amounts of Cd. Production of element-enriched biomass with value as ore or fertilizer or improved food (Se) or feed supplement may offset costs of phytoextraction crop production. Transgenic phytoextraction plants have been achieved for Hg, but not for other elements. Although several researchers have been attempting to clone all genes required for effective hyperaccumulation of several elements, success appears years away; such demonstrations will be needed to prove we have identified all necessary processes in hyperaccumulation.     

<Emphasis Type="Italic">A Posteriori</Emphasis> Evaluation of Strategies of Management: The Effectiveness of No-Wash Zones in Minimizing the Impacts of Boat-Wash on Macrobenthic Infauna

Wind-driven waves are important in structuring intertidal and shallow subtidal assemblages of macrobenthic infauna. In the sheltered waters of estuaries, boat-generated waves (wash) may play a similar role because they are typically of a similar amplitude or larger than wind-driven waves. However, few studies have attempted to determine the role of wash in structuring assemblages. Consequently, strategies for managing boating focus around minimization of bank erosion. Along the Parramatta River (Sydney, Australia), no-wash zones have been established and mangroves planted to minimize the erosion of riverbanks and collapse of seawalls purportedly caused by 35-m-long RiverCat ferries. Although intended to also reduce the ecological impacts of wash, it is unclear whether these strategies achieve this goal. Unvegetated and vegetated (among the pneumatophores of mangroves) sediments were sampled in wash and no-wash zones along the Parramatta River to assess the effectiveness of no-wash zones and vegetation of river banks in reducing the ecological impacts of wash. Specifically, it was hypothesized that (1) assemblages of intertidal macrobenthic infauna would differ between wash and no-wash zones of the Parramatta River and (2) these differences would be greater in unvegetated than in vegetated habitat. As predicted, assemblages of macrobenthic infauna differed between the wash and no-wash zones. Capitellids, nereids, and spionids were more abundant in the no-wash zone. Contrary to the hypothesis, differences were no greater in the unvegetated habitat than in the vegetated habitat. The results suggest an impact of wash on assemblages of macrobenthic infauana and a role for no-wash zones in minimizing the effects of this disturbance.     

GPS tracking a marine predator: the effects of precision,resolution and sampling rate on foraging tracks of African Penguins

We used a prototype GPS logger to track the movements of breeding African Penguins (Spheniscus demersus). The loggers also recorded temperature and water depth, which allowed us to reconstruct foraging tracks in three dimensions, although GPS signals are interrupted when the birds dive. Here we report the loggers performance in the field and assess the effects of GPS error, resolution and sampling rate on estimates of foraging track length and speed. There is a trade-off between sampling rate and battery lifespan. We tested loggers at sampling intervals of 1 s, 10 s, 1 min, 2 min and 10 min. Sampling less frequently increases the chance of tracking an entire foraging trip, but it slows uplink times, slightly decreases the accuracy of positional fixes, and significantly reduces the ability to measure fine-scale aspects of foraging behaviour. Compared with radio or satellite tracking, GPS loggers offer unprecedented detail about animal movements. The results of our analysis suggest that techniques that sample relatively infrequently, such as satellite tracking, underestimate actual track lengths by up to 50%. However, caution is needed when interpreting fine-scale sampling for relatively slow-moving organisms. Re-sampling 1-s tracks suggests that c. 35% of apparent movements at this scale are due to measurement error and, more importantly, the limited spatial resolution of GPS (1.85×1.54 m at the study area). We recommend that researchers use a 1-s sampling rate for fine-scale studies, but resample at less frequent intervals to remove spurious noise for slow-moving animals. At current levels of resolution, animals should move at least 4 m per sampling interval. We provide empirical correction factors to compare inferred track length sampled at different rates, but caution that these are idiosyncratic and strongly dependent on the animals behaviour. Overall, GPS loggers offer a significant advance for studies of fine-scale animal movement patterns.Communicated by O. Kinne, Oldendorf/Luhe