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Bioplastics are alternatives of conventional petroleum-based plastics. Bioplastics are polymers processed from renewable sources and are biodegradable. This study aims at conducting an environmental impact assessment of the bioprocessing of agricultural wastes into bioplastics compared to petro-plastics using an LCA approach. Bioplastics were produced from potato peels in laboratory. In a biochemical reaction under heating, starch was extracted from peels and glycerin, vinegar and water were added with a range of different ratios, which resulted in producing different samples of bio-based plastics. Nevertheless, the environmental impact of the bioplastics production process was evaluated and compared to petro-plastics. A life cycle analysis of bioplastics produced in laboratory and petro-plastics was conducted. The results are presented in the form of global warming potential, and other environmental impacts including acidification potential, eutrophication potential, freshwater ecotoxicity potential, human toxicity potential, and ozone layer depletion of producing bioplastics are compared to petro-plastics. The results show that the greenhouse gases (GHG) emissions, through the different experiments to produce bioplastics, range between 0.354 and 0.623 kg CO2 eq. per kg bioplastic compared to 2.37 kg CO2 eq. per kg polypropylene as a petro-plastic. The results also showed that there are no significant potential effects for the bioplastics produced from potato peels on different environmental impacts in comparison with poly-β-hydroxybutyric acid and polypropylene. Thus, the bioplastics produced from agricultural wastes can be manufactured in industrial scale to reduce the dependence on petroleum-based plastics. This in turn will mitigate GHG emissions and reduce the negative environmental impacts on climate change.

In a former study, a German lignite extract exhibited toxicity to Danio rerio and Caenorhabditis elegans and was shown to have mutagenic and dioxin-like activity. Besides the comparatively low content of known toxic polycyclic aromatic hydrocarbons (PAH), highly intensive peaks of m/z 274 and m/z 324 were observed during the chromatographic analysis. These compounds are assumed to be alkylated chrysenes and picenes (3,3,7-trimethyl-1,2,3,4-tetrahydrochrysene, 1,2-(1'-isopropylpropano)-7-methylchrysene and an isomer of the latter, 1,2,9-trimethyl-1,2,3,4-tetrahydropicene and 2,2,9-trimethyl-1,2,3,4-tetrahydropicene). These compounds are intermediates in the diagenetic formation of chrysene and picene from triterpenoids. Due to their general high abundance in lignites and the toxicity observed for the lignite extract, the mechanism-specific toxicity and bioavailability of these compounds were investigated in the present study using the approach of effect-directed analysis. After the separation of the compounds from other PAH, their mutagenic activity (Ames Fluctuation test) and dioxin-like activity (EROD activity) were studied. Both, mutation induction factor (up to 2.9±2.7) and dioxin-like activity (Bio-TEQ of 224±75 pg/g; represents the amount (pg) 2,3,7,8-tetrachlorodibenzo-p-dioxin per g coal that would provoke the same toxic effect) were rather low. Bioavailability estimated by the bioaccumulation test with Lumbriculus variegatus was also very limited. Based on the obtained results, the environmental risk of the highly abundant alkylated chrysenes and picenes in lignites is concluded to be low.

Abstract Integrated coal gasification combined cycle (IGCC) power plants have been looked to as a key technology for the 21st century in order to realize high efficiency and good environmental performance for electricity generation, replacing existing coal fired power plants. Following successful completion of a 200 ton/d pilot project in Nakoso, IGCC technology development in Japan is moving from the stage of a feasibility study to a detailed study to allow final decisions for demonstration plant construction. The feasibility study, jointly conducted by the domestic electric power companies, found MHI's IGCC technology to have several advantages in efficiency and reliability. In parallel with the study, a number of R&D tests have been executed as a national project to facilitate scaling up from the pilot plant to the demonstration plant. This paper introduces the current status of the MHI's IGCC technological development.

Abstract Waste disposal is a core issue worldwide. Different researches are being carried out in order to handle waste materials, generated in industrial production and application processes, e.g. paint residue from metal coating in the automobile industry. Often waste is disposed in landfills at substantial economic and environmental cost. Combustion is another way to get rid of possibly hazardous waste. Pulverized fuel combustion is one of the latest combustion technologies. However, pulverized fuel combustion faces severe problems if the waste (fuel) contains components with low melting point. Having a low melting point, it gets difficult to manage and convey the pulverized material to the hot combustion chamber. The melting of fuel causes clogging in the fuel transport nozzle used to convey the material into the combustion chamber. In this work, a new technology for combustion of materials with low melting points is proposed, focusing on apparatus and nozzle design to prevent clogging. For this purpose, different nozzle designs were evaluated by multi-phase CFD simulations. Two sets of nozzle air flow rates were used in four nozzles. Effect of different flow rates and fuel particle size on combustion temperatures are also discussed. It was noted that nozzle air flow rate has a strong influence on the temperature distributions. Small fuel particle sizes result in wider combustion zones while larger particles give longer combustion zones. The results come up with optimized nozzle design and nozzle air flow for transportation of pulverized material with low melting point.

Recently, studies have appeared pointing out that aerosols can dominate the total amine emission from amine based PCCC pilot plant scale installations. For the design of countermeasure types (upstream or downstream of the PCCC installation), it is crucial to have an idea of the aerosol size distribution and numbers entering or leaving the absorber. This study is the first to present this kind of data and should serve future installations when designing aerosol emission countermeasures. H2SO4 aerosols entering the absorber are observed to be extremely small (i.e. <0.2μm) with number concentrations exceeding 1E8cm-3. The aerosols grow in size as they travel through the absorber through the taking up of water and amine to sizes close to but staying below 1μm. However, despite the fact that most of the aerosols (expressed in number concentrations) are well below 1μm, most of the water (and thus amine) is found in the aerosol sizes between 0.5 and 2μm. Therefore, if one aims at designing efficient countermeasures, eliminating this size fraction is crucial. This amine emission stream is therefore very difficult to remove using water washes as aerosols are known to travel through water wash sections. Moreover, also classical demisters show very little efficiency for these small aerosol sizes and are therefore believed not to be suitable for the removal of aerosols. This information will therefore serve future installations when designing aerosol emission countermeasures. © 2014 Elsevier Ltd.

Abstract Bioenergy systems are expected to expand over the coming decades due to their potential to address energy security and environmental pollution challenges. Nevertheless, any renewable energy project can only survive if approved environmentally superior to its conventional counterparts. Life cycle assessment (LCA) is an internationally standardized and validated methodology to evaluate and quantify the environmental impacts of bioenergy systems. However, due to its methodological scope, the LCA method measures only the environmental consequences of the target products of energy systems. The LCA approach can neither allocate the environmental impacts at the component level nor measure the environmental impacts of intermediate products. These challenges can be substantially resolved by systematically integrating the LCA approach with the thermodynamically-rooted exergy, offering a powerful environmental sustainability assessment tool known as “exergoenvironmental analysis“. Due to the unique methodological and conceptual characteristics of exergoenvironmental analysis in revealing the possibilities and trends for improvement, it has recently received increasing attention to mitigate the environmental impacts of bioenergy systems. Therefore, this review is aimed to thoroughly summarize and critically discuss the evaluation of sustainability aspects of bioenergy systems based on exergoenvironmental analysis. The pros and cons of using exergoenvironmental analysis in bioenergy research are also outlined to identify possible future directions for the field. Overall, exergoenvironmental analysis can offer more detailed information on the environmental consequences of each flow and component of bioenergy production plants, thereby diagnosing the breakthrough points for additional environmental improvements.

Abstract A general method for realistic performance evaluation of solar control properties of facades for facades with sun-shading or other solar control systems has been developed. It is particularly designed to be used for venetian blinds. It can be used used ‘stand-alone’ or within building simulation programs. The new method has proven to be of great practical value to planning teams of huge office buildings in Germany, Austria and Switzerland. The method is presented in detail in this paper. It can be used either ’stand-alone’ (without building simulation) for comparisons of different facade variants or within building simulation programs. Some parts of the proposed methodology could be used in standards (e.g. EN13363) or to improve the accuracy of building simulation programs which are currently on the market. Practical experience with the new methodology led to insights which are the basis for the design of two new products. These new products are compared with state of the art products in [T.E. Kuhn, Solar control: comparsion of two new systems with the state of the art on the basis of a new general evaluation method for facades with venetian blinds or other solar control systems, Energy and Buildings, in press] on the basis of the new methodology.

Abstract This work reports the development of a near-infrared (NIR) spectroscopy online calibration for monitoring volatile solids (VS) and total volatile fatty acids (VFA) process parameters during anaerobic digestion (AD). The objective was to investigate its potential to estimate the dynamics of AD process parameters after feeding events. A recirculation loop was employed to record online measurements during an eight-month experiment using a 3.3 m 3 pilot plant fed with maize silage under mesophilic conditions. Sampling was performed to conduct calibrations and subsequent test-set validations, comparing the NIR spectroscopy estimates to the reference values. The calibrated accuracy in terms of mean prediction errors (RMSEP) was 3 g kg −1 for VS and 0.9 g kg −1 for VFA in the fresh matter. By applying the calibrations to time series spectra, the model accuracy provided adequate indications of the concentration changes, including highly sensitive monitoring of short-term VFA dynamics.