Chelating agents, molecules that very strongly coordinates certain metal ions, are used industrially as well as in consumer products to minimize disturbances and increase performance of reactions and applications. The widely used sequestering agents, nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) belong to this branch of readily water-soluble compounds. When these chemical structures also have hydrophobic parts, they are prone to adsorb at air-water interfaces and to self-assemble. Such bifunctional molecules can be called chelating surfactants and will have more extended utilization prospects than common chelating agents or ordinary ionic surfactants. The present review attempts to highlight the fundamental behavior of chelating surfactants in solution and at interfaces, and their very specific interactions with metal ions. Methods to recover chelating surfactants from metal chelates are also described. Moreover, utilization of chelating surfactants in applications for metal removal in environmental engineering and mineral processing, as well as for metal control in the fields of biology, chemistry and physics, is exemplified and discussed.
With increasing demand for forest biofuels the pressures on ecosystem services from forestry practices willincrease. This calls for identification and assessment of tradeoffs between different uses of provisioning and otherecosystem services and establish management practices considering such tradeoffs.
This Green IT case study commissioned by Försäkringskassan (FK), the Swedish National Social Insurance Agency, quantifies the environmental performance of the IT infrastructure (IT-IS) in use during 2010 in a lifecycle perspective. Adopting a system view in Green IT analysis can mitigate risks of problem shifts. IT-IS concerns the equipment that enables office automation and external web application services. The size of the FK IT-IS is in the order of 300 branch offices with 14000 pc’s, 2100 printers and a 1 MW data centre hosting 1200 servers, 5 Petabyte of central data storage and serving about 80 key business applications.
The carbon footprint of the FK IT-IS in 2010 accounts to 6.5 kiloton CO2-equivalents. The total environmental impact is calculated across 18 themes and expressed as a single indicator eco score amounting to 822.000 ReCiPe points.
The contribution of capital goods is large with 44% of the carbon footprint and 47% of the eco score linked to emissions embedded in material equipment. The environmental effects from distributed IT deployed at local office sites, dominate at two thirds of the total FK IT-IS impacts. Important drivers in the local office sites category are the relatively short economic life span of pc equipment and the significant volume of paper consumed in printing activities.
Within the data centre category, operational processes dominate the environmental impacts and are linked to intensive power use. In comparison to industry benchmark scores, the data centre infrastructure energy efficiency (DCiE) is relatively low at 57%, or 59% when credited for waste heat utilisation. Airflow containment measures in computer rooms are identified for efficiency improvement. Enhanced airflow controls also act as a prerequisite to better leverage opportunities for free cooling present at the location in northern Europe. With regards to the data centre hosted IT, environmental impacts linked to storage services dominate and remarkably exceed those of servers.
There are indications of Data Centres being nodes for environmental impacts in IT solutions, but due to reasons connected to protection of business core assets, few open studies on such centres exist. This LCA case-study of the Swedish National Insurance Agency Data Centre in Sundsvall confirms and quantifies the significance of the environmental load posed by the data centre. The centre increases the IT carbon footprint by more than half (54%) relative to the institutes PC equipment fleet. In the operational phase, climate change contributions are more than double to that of PC use. Environmental impact stemming from embedded emissions in data centre capital infrastructure is significant (33%) given the relative short economic lifetime of the IT hardware. Even within the cold climate geographical zone, about a third (32%) of data centre supplied energy is consumed by air-conditioning thus offering opportunities to further leverage free cooling
Evaluation of sustainable work within real-estate companies is a relativelynew way of working and the number of companies starting towork with this routine increases every day. Chalmersfastigheter is areal-estate company providing faculties for universities. The company ismainly focusing on decision-making and outsourcing.
The aim of this essay is to evaluate decision-making processes andensuring that the right decision is made, with other words, evaluatingthe decision and not the result from the decision. By identifying whatsustainability means for Chalmersfastigheter and in which processesdecisions are made, an evaluation is easily made to see if every decisionis based on the three aspects of sustainability; ecology, economy andsocial. The result from this evaluation will highlight how Chalmersfastigheter prioritize in decisions concerning sustainabledevelopment.
This study is based on the ISO 14001 standard and the definition ofsustainable development presented in the Brundtland report.Akademiska Hus is used as an example to present how another companyin the same business has operationalized sustainability. This study ismade on a request from Chalmersfastigheter and shall hopefully resultin a routine which becomes a part of their environmental managementsystem.
The purpose of this paper is to present a pilot educational project where ecological modelling has been used to integrate advanced level students into the research about regional sustainability. Addressing regional sustainability with an ecological systems model based on carbon and energy balances is a way to understand the basics of sustainability integrating detail and holistic views. Such model has been developed in a case study on the Danish island Samsø and currently a similar model is now being developed for the Jämtland county. Even though Jämtland, located in mid Sweden, is a sparsely populated area with large forests, a lot of hydro power, and only one major city, it is still not obvious how to reach long term sustainability. For educational purposes ecological models are excellent tools, since complex interactions can be studied, analysed and discussed in a structured way. It can be expected future sustainable society development presupposes integration between research and education, thus building a long term strategy for the possibilities to change negative cultural patters of whatever kind these might be. To strengthen the authorisation of the education for sustainability, clarification of the university’s integrative role in society may well be used, to give students self-confidence for continuous development within the field.
According to the ISO14020 standard eco-labeling of products is intended to guide consumers towards the more environmentally friendly segment of products available on the market. To investigate if this is successful for laptop computers, a life cycle assessment (LCA) model of a generic, up to date laptop was created. The constraints imposed by two different eco-labels for laptops were implemented in the LCA model; the eco-labels used for this purpose were EPEAT (based in the US) and TCO (based in Sweden). The analysis of the eco-labels criteria revealed that the labels impose few changes on the design of the laptop as describe in the LCA model and that their influence on the life cycle impact was minimal. The labels do promote energy efficiency, but the marked demand for long battery life is a push so strong that the average lap top on the market well fulfills these criteria. It was notable that the lap top power efficiency together with short product life, resulted in that the use phase environmental impacts was less compared to the production phase environmental impacts (partly opposed to some earlier studies, where the electricity consumption during use was a more important driver). To promote better environmental performance the energy efficiency could be improved further; but useful life of lap tops is an increasingly important issue to be addressed. Criteria for eco-labels must be continuously updated to actually guide toward a more environmentally friendly market segment for fast developing products like electronics.
District heating has the potential to provide consumers with heat using resources that would otherwise be wasted (e.g. surplus heat from industry) or increase overall efficiency by generating both heat and electricity. However, the introduction and utilisation of district heating has to be performed in a responsible way in order to benefit all the different stakeholders involved. A positive outcome depends on local preconditions and the identification of trade-offs involving different environmental, social and economic considerations. In the history of district heating, several illustrative articulations of sustainability can be found, and situations in which different trade-offs have become clear.
This chapter will discuss some articulations of sustainability and the environmental, social and economic trade-offs that can be identified for district heat distribution systems, to help achieve a deeper understanding of sustainability considerations and trade-offs for technical systems in general. Examples from research on district heating, carried out at Chalmers University of Technology from 1991 until today, will be used to illustrate real-world dilemmas.