Distribution of copper,silver and gold during thermal treatment with brominated flame retardants

The growing consumption of electric and electronic equipment results in creating an increasing amount of electronic waste. The most economically and environmentally advantageous methods for the treatment and recycling of waste electric and electronic equipment (WEEE) are the thermal techniques such as direct combustion, co-combustion with plastic wastes, pyrolysis and gasification. Nowadays, this kind of waste is mainly thermally treated in incinerators (e.g. rotary kilns) to decompose the plastics present, and to concentrate metals in bottom ash. The concentrated metals (e.g. copper, precious metals) can be supplied as a secondary raw material to metal smelters, while the pyrolysis of plastics allows the recovery of fuel gases, volatilising agents and, eventually, energy. Indeed, WEEE, such as a printed circuit boards (PCBs) usually contains brominated flame retardants (BFRs). From these materials, hydrobromic acid (HBr) is formed as a product of their thermal decomposition.In the present work, the bromination was studied of copper, silver and gold by HBr, originating from BFRs, such as Tetrabromobisphenol A (TBBPA) and Tetrabromobisphenol A-Tetrabromobisophenol A diglycidyl ether (TTDE) polymer; possible volatilization of the bromides formed was monitored using a thermo-gravimetric analyzer (TGA) and a laboratory-scale furnace for treating samples of metals and BFRs under an inert atmosphere and at a wide range of temperatures. The results obtained indicate that up to about 50% of copper and silver can evolve from sample residues in the form of volatile CuBr and AgBr above 600 and 1000 °C, respectively. The reactions occur in the molten resin phase simultaneously with the decomposition of the brominated resin. Gold is resistant to HBr and remains unchanged in the residue.     

Multi-level perspectives with technology readiness measures for aviation innovation

Sustainability science requires the development of a theoretical framework to understand, analyze, and design innovation to solve social, economic, and environmental issues. This paper extends the framework of multi-level perspectives (MLP) by introducing a technology readiness level (TRL), and analyzes the innovation of the advanced turboprop (ATP) engine in the aviation industry, also known as a propfan or an open rotor engine, which is one of the most promising engine innovations expected to mitigate climate change. The concept of TRL was introduced to explain the mechanisms of ATP failure in the late 1980s as well as the transition of the geared turbofan (GTF). In this paper, we discuss why ATP and GTF faced different fates although both were developed under the same landscape in the aviation industry. We also discuss the different roles of the socio-technical regime, such as uneven and dynamic opportunity windows, technological readiness, niche stock, institutional support of export products, and the risk of a ‘launch’ customer, at different TRLs. As illustrated in this paper, MLP with TRL is expected to facilitate future interdisciplinary collaboration between social scientists and engineers, and also transdisciplinary expertise between academia and practitioners by supporting analysis and design of the industry’s transition toward a more environmentally friendly regime as well as its effective management.     

Dioxin concentration in human milk in Hebei province in China and Tokyo, Japan: potential dietary risk factors and determination of possible sources

Very limited information is available on body burdens and environmental levels of dioxins and dioxin-like PCBs (dl-PCBs) in mainland China. In the current studies, human milk samples were collected from 30 breastfeeding mothers in Shijiazhuang city (industrialized) and 11 in the Tanshan countryside (agricultural) of Hebei Province in northern China. An additional 20 samples were obtained from mothers in Tokyo, Japan. PCDDs, PCDFs, and dl-PCBs in human milk were analyzed by high-resolution gas chromatography/high-resolution mass spectrometry. Our results show that arithmetic means for body burdens of PCDDs/Fs and dl-PCBs in Hebei were 3.6 and 1.9 pg TEQ g⁻¹ fat, respectively, which were only about one fourth of the levels in Japan. In addition, no difference was found in the chemical levels except dl-PCBs between the urban and rural areas. Based on the results of an in-person interview of the Chinese mothers using a 59-item questionnaire, freshwater fish consumption was found to correlate with the body burden of dioxins. Principal component analysis of dioxin congeners revealed that the patterns of dioxins in the Hebei urban and rural areas are quite similar; however, they are clearly different from those in Japan. Collectively, our results suggest that the lower body burdens of dioxin in Hebei may be due in part to the relatively slow industrialization and a lower consumption of marine foods. Finally, the results indicate that comprehensive monitoring of dioxins and dl-PCBs in humans as well as in the environment and foods is necessary in China.     

Greenhouse gas emissions in Canada and Japan: sector-specific estimates and managerial and economic implications

Many firms generate large amounts of carbon dioxide and other greenhouse gases when they burn fossil fuels in their production processes. In addition, production of raw materials and other inputs the firms procure for their operations also generates greenhouse gases indirectly. These direct and indirect greenhouse gas emissions occur in many sectors of our economies. In this paper, we first present sector-specific estimates for such greenhouse gas emissions. We then show that estimates for such sector-specific greenhouse gas emissions are often required for various types of corporate as well as public policy analyses in both domestic and international contexts. Measuring greenhouse gas emissions resulting from firms' multi-stage production processes in a multi-sector context is relevant for policies related to the Kyoto protocol, an international agreement to limit global greenhouse gas emissions. For example, since the protocol allows firms to engage in trading and offsetting of their greenhouse gas emissions across national borders, provided that emissions are correctly measured, the firms can take advantage of such trading schemes by placing their energy-intensive production facilities globally and strategically. We present several case studies which illustrate the importance of this and other aspects of greenhouse gas emissions in firms' environmental management. We also argue that our modeling and estimation methods based on input-output analyses are suitable for the types of research goals we have in this paper. Our methods are applied to data for Canada and Japan in a variety of environmental management circumstances.     

Mercury volatilization by the most mercury-resistant bacteria from the seawater of Minamata Bay in various physiological conditions

The volatilization of mercuric chloride (HgCl₂) and methyl mercuric chloride (CH₃HgCl) by the 45 strains (35 Pseudoalteromonas sp., 2 Vibrio sp., 1 Aeromonas sp., and 7 unclassified) of the most mercury-resistant bacteria from Minamata Bay seawater was examined in various physiological conditions. The bacteria could grow and volatilize HgCl₂ in the liquid medium containing 1-10% NaCl. Two Pseudoalteromonas strains could grow and volatilize HgCl₂ at pH levels ranging from 5.0 to 10.0. The resting cells of 43 strains could volatilize HgCl₂ at concentrations ranging from 30 to 68% after 1-h incubation at 30vv°C. The resting cells of 41 strains could volatilize CH₃HgCl at concentrations ranging from 13 to 88% after 1-h incubation at 30vv°C. Ninety-two percent of mercury was removed from the phosphate buffer containing 0.1 7g/ml by a resting cell of Pseudoalteromonas strain H-4 after 30-min incubation at 30vv°C. We were able to screen the special bacteria, which could volatilize mercury compounds at a high rate in various physiological conditions, for the purpose of developing mercury removal methods using bacteria.     

日本Biwa 糊- Yodo河水体系的可持续管理

Biwa湖 Yodo河水系为主要的居民中心及其周围的市政机构提供城市用水和工业用水 .它也提供农业用水，主要在 Biwa湖排水区域 .该水系服务的人口总数约为 1400万人 . 这个水系构成了 Keihanshin工业区的主要部分（按照字面上是指京都、大阪和神户），这是一个以沿大阪海湾－濑户内海的狭长地带发展为特征的一个区域 .Keihanshin的工业产值居日本的第三位，约占国内生产总值的 12.4％ .一个复杂的供水网和废水网支持着高水平的工业和农业活动 .     

日本Biwai湖-Yodo河水体系的可持续管理

Biwa湖-Yodo河水系为主要的居民中心及其周围的市政机构提供城市用水和工业用水 .它也提供农业用水，主要在 Biwa湖排水区域 .该水系服务的人口总数约为 1400万人 . 　　这个水系构成了 Keihanshin工业区的主要部分（按照字面上是指京都、大阪和神户），这是一个以沿大阪海湾－濑户内海的狭长地带发展为特征的一个区域 .Keihanshin的工业产值居日本的第三位，约占国内生产总值的 12.4％ .一个复杂的供水网和废水网支持着高水平的工业和农业活动 .……