Environments, Volume 5, Issue 6 (June 2018) – 10 articles

The disposal of discarded tyres represents an environmental challenge for solid waste management entities. The need to reduce solid waste in urban areas along with the depletion of natural resources have made it necessary to reincorporate used materials into productive processes, giving value to what is considered waste, and minimizing the requirement of natural resources. In this study, pyrolysis was selected to thermally decompose used ground waste vulcanized rubber from automobile tyres. This rubber was exposed to the pyrolytic process in an indirectly heated batch reactor at three different temperatures. Three fractions (i.e., gas, liquid and solid) were obtained during the process. The effect of a hydrogen stream on the properties of the liquid fraction was analysed and characterized following the American Society for Testing and Materials procedures (ASTM) for the pyrolysis of liquid fuels. A multifactorial statistical analysis was used to evaluate the experimental data and thermographs of the process were recorded. Differences in thermographs suggest a different degradation pathway for the rubber exposed to 600 °C compared to the rubber exposed to lower temperatures. Temperatures in the range of 450 to 500 °C favored the production of carbon black regardless of the use of a hydrogen stream. In contrast, high temperatures favored the production of liquid and gas fractions. The highest production of liquid fraction was obtained at 550 °C, where 37% of the rubber was turned into liquid. Results also showed that a constant flow of hydrogen improves the appearance of the pyrolysis liquid. Furthermore, the hydrogen atmosphere reduces the sulphur content, water and sediments; and increases the values for the heat of combustion and the liquid fraction. Full article

Reverse osmosis (RO) was studied to reduce salinity of flue gas desulfurization (FGD) wastewaters after softening with Na₂CO₃·H₂O and ultrafiltration (UF). Two commercial thin film composite polyamide RO membranes (SWC-2540 and ESPA-2540, from Hydranautics) in spiral-wound configuration were tested and their performance in terms of salinity reduction as well as permeate flux, fouling index and water recovery was evaluated. Experimental runs were performed according to the feed and bleed configuration in selected operating conditions. For the SWC-2540 membrane experiments were also performed in total recycle configuration in order to evaluate the effect of operating pressure on permeate flux and quality. Experimental results indicated that the SWC-2540 membrane showed a better performance in the rejection of ions: Mg²⁺ ions were completely rejected, while the rejection towards monovalent ions such as Na⁺ was of about 95.5%. The ESPA-2540 membrane showed rejections towards Ca²⁺ and Mg²⁺ higher than 86.5% whilst the observed rejection towards Na⁺ was of 80%. For the SWC-2540 membrane an increased rejection for Ca²⁺ and Na⁺ ions was observed by increasing the operating pressure in the range 16-50 bar. Mg²⁺ ions were totally rejected independently by the operating pressure. Full article

In recent years, adaptation measures such as awnings, louvers, directional reflective materials, mist sprays, and evaporative materials, have been developed with the expectation that they will serve as effective solutions to outdoor human thermal environments that are under the influence of urban heat island. A simple method to evaluate the aforementioned adaptation measures is examined in this study, focusing on their appropriate introduction on urban space. The influence of the solar transmittance of adaptation measures such as shading, on mean radiant temperature (MRT) is approximately 1.5 °C per 0.10. If a shielding device that reflects a large amount of solar radiation and facilitates high levels of evaporation is developed, MRT and standard new effective temperature (SET*) will both decrease. Full article

The aim of this experimental study was to assess the feasibility of using a wet oxidation (WO) process for treating fine soil with a high level of total petroleum hydrocarbons (TPHs). Two samples of soil were spiked with two different contaminants (motor oil, and motor oil + diesel). The samples were subjected to a WO bench plant test, where the effect of the main process parameters (i.e., temperature and reaction time) on the removal of TPHs was investigated. Results show that the WO process is effective for the decontamination of hydrocarbons, and a strong reduction (>85%) can be obtained with the typical working conditions of a full-scale plant (temperature = 250 °C, reaction time = 30 min). The solid residue resulting from the WO process was characterized in order to evaluate the recovery options. In terms of chemical characterization, the contents of the pollutants comply with the Italian regulations for commercial and industrial site use. Moreover, the results of the leaching test suggested that these residues could be reused for ceramic and brick manufacturing processes. Full article

Green infrastructure (GI) stormwater control measures (SCMs), such as permeable pavement systems, are common practices used for controlling stormwater runoff. In this paper, two permeable pavement strips were studied to quantify their water quality performance. The quality monitoring was coupled with comprehensive rainfall analysis to investigate the effects of common rainfall characteristics on the quality performance of the systems. The pavements utilized deep aggregate layers to promote higher infiltration, and were installed in parking lanes of an urban neighborhood. Water quality samples were collected from upgradient stormwater runoff and from stormwater captured by the permeable pavements. In addition to total suspended solids (TSS), nutrients, and dissolved metals, this research also investigated bacterial contamination (Escherichia coli, E. coli). The results indicated that the two permeable pavement systems significantly reduced concentrations of TSS, E. coli, total phosphorus, and ammonia. The average reductions of TSS and E. coli between the two systems were 47% and 69%, respectively. It was also observed that pollutant loadings in the stormwater runoff, as well as pollutant reductions, were affected by the intensity of sampled rainfall events. Thus, it is suggested to consider the effects of rainfall characteristics when reporting the water quality benefits of stormwater GIs. Full article

Marine spatial planning temporally and spatially allocates marine resources to different users. The ecosystem approach aims at optimising the social and economic benefits people derive from marine resources while preserving the ecosystem’s health. Marine ecosystem services are defined as the benefits people obtain from marine ecosystems. The aim of this study is to determine which interrelations between marine ecosystem services and the marine energy industry can be identified for use in transnational marine spatial planning exemplified in the North Sea region. As the North Sea is one of the busiest seas worldwide, the risk of impairing the ecosystems through anthropogenic pressures is high. Drawing on a literature-based review, 23 marine ecosystem services provided by the North Sea region were defined and linked to seven offshore energy fields comprising oil and natural gas, wind, tides and currents, waves, salinity gradients, algal biomass, and geothermal heat. The interactions were divided into four categories: dependence, impact, bidirectional, or no interaction. Oil and natural gas, as well as algae biomass, are the fields with the most relations with marine ecosystem services while waves and salinity gradients exhibit the least. Some marine ecosystem services (Conditions for Infrastructure, Regulation of Water Flows, and Cognitive Development) are needed for all fields; Recreation and Tourism, Aesthetic and Cultural Perceptions and Traditions, Cognitive Development, and Sea Scape are impacted by all fields. The results of this research provide an improved basis for an ecosystem approach in transnational marine spatial planning. Full article

An action learning course is an academic course which involves academic learning and social activities, and has an impact on the community. In the last year, students from the HIT, Holon Institute of Technology, participated in the action learning course “Green Ambassador”, which aimed to teach pupils about renewable energy and preserving an environment. As part of the course requirements, students were asked to conduct enjoyable lessons for fifth and sixth grade pupils in the Arabic elementary school “Alomaria” situated in the city of Ramle. During lessons held within the school, the students taught the pupils via games and activities what is soil contamination, how to turn waste into a resource, what is an air pollution, energy conversion and etc. In order to illustrate the topics studied by the pupils, the students used a moveable laboratory containing demonstrations, experiments and creative activities. Thus, active participation of the pupils in the lessons was achieved. The results show higher rates of success in the final questionnaires on the lessons’ topics and involvement, due to an enriching and a challenging experience of learning. Thanks to the action learning course, the pupils became more aware and learned an important lesson about the ways to preserve the environment. Full article

In this study, leachate and sediment samples were collected from the leachate drains, ponds and waste pits of three landfills in the Indochina peninsula to investigate the level of contamination of biochemical parameters, especially heavy metals. In-situ and laboratory measurements were conducted, together with site surveys to discuss the effects of site characteristics on leachate qualities. It was confirmed from the investigation that the changes in leachate qualities are mainly caused by the landfill site conditions, e.g., soil cover, the waste compaction level, waste thickness, dumping method, and leachate storage, and that these conditions lead to different levels of dilution and biochemical reaction of the leachate. Most of the biochemical parameters of the fresh leachates were greater than the effluent standards, and showed higher concentrations than those measured for the leachate in large storage ponds. The concentrations of the parameters were higher in the dry season than the wet season for all fresh leachate samples, but no significant seasonal difference was observed in the large leachate storage ponds. The majority of heavy metals were partitioned in the suspended solids, and no clear seasonal change of heavy metal contents was contained in the suspended solids and sediment samples. Full article

Within the frame of European directive 2002/49 for Strategic Noise Mapping and the relevant environmental Noise Action Plans, which included preparation for the management of environmental noise and the rehabilitation of the sound environment, Greece had the opportunity to develop an innovative and comprehensive methodology to analyze the sound environments of several urban and semi-urban residential neighborhoods in the large and medium-size cities of the country e.g., Volos, Larissa, Heraklion, Chania, Agrinio, Corfu, and Thessaloniki, between 2012 and 2016. This paper presents the determined multidisciplinary approach, showing how the environmental noise data are cross-analyzed with urban and architectural data and perception descriptors by inhabitants. Furthermore, it shows how these specific results have been implemented in the developed noise actions plans that have been proposed to the authorities for immediate implementation. Finally, the paper discusses the necessary development of this approach to reduce noise exposure problems, as well as assist the cities in their evolution toward the introduction of a sustainable urban sound environment. Full article

We aimed to determine the effect of Luria-Bertani (LB) medium, nutrient broth (NB) and tryptic soy broth (TSB), pH, temperature, and incubation time on the production of extracellular polysaccharides (EPS). The effect of glucose, whey and glycerol on bacterial EPS production by Bacillus pseudomycoides U10 was also tested. LB was better than NB and TSB for EPS production. Maximum EPS production was obtained when 1 g/L whey was added to the growth medium. The influence of incubation times (24–96 h), different pH values (6.5, 7.0, 7.5, 8.0 and 9.0) and temperature (25, 30, 37 and 45 °C) were also tested. The optimum pH level was 7.0 and the highest EPS production was observed at 37 °C after 60 h of incubation. Glycerol was not a good carbon source for cell growth and EPS production. The difference in carbohydrate and protein amount was related to the different types of EPS (dissolved and particulate). In general, the uronic acid content in particulate EPS was lower than in dissolved EPS. The maximum uronic acid was obtained from dissolved EPS (16 mg uronic acid/g EPS). According to X-ray diffraction (XRD), thermogravimetric EPS have a poorly crystalline nature and exhibit two-step degradations, corresponding to the weight loss of moisture and/or carboxyl group and the pyrolysis of EPS, without distinctive changes in different media conditions. Small-angle X-ray scattering (SAXS) data indicate the layer thickness of the bacterial EPS is from 12.04 to 14.07 Å for whey and dissolved LB conditions, respectively. It was found that EPS structures changed with whey addition, such as higher d-values, lower weight losses and more filamentous structures which seemed to be related to increasing durability and/or stability. Full article