Sources of environmental impact

For polyester producing processes, the following sources of environmental impact have been identified  

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Simply put, paper is manufactured by applying a watery suspension of cellulose fibers to a screen that allows the water to drain and leaves the fibrous particles behind in a web. Most modem paper products contain nonfibrous additives, but otherwise they fall within this general definition. Only a few paper products for specialized uses are created without the use of water, using dry forming techniques. The production of pulp is the major source of environmental impacts from the pulp and paper industry. 

Biodegradability can bring benefits in specific applications, particularly at the end of life of some plastics products but it is not an end by itself and it should be highlighted that end-of-life is generally not the main source of environmental impact in a product life. Fitness for use is the main driver for plastic type selection for any application and, in the perspective of an optimised use of existing resources, eco-efficiency over the whole life cycle should be the main criterion against which the combined environmental and economic impacts of any product have to be assessed. 

Negative externalities arise when an action by an individual or a group implies harmful effects on others such as unintended dispersion of chemicals to land, air and water air pollution effects on health forest growth or fish reproduction. When negative externalities are generated they should be internalized into the market economy. By internalizing the externalities the economic value of environmental impacts are allocated to the pollution sources and included in the economics of the activities causing the problem. This would also allow for the market to function properly and thereby reach a socially optimal level of environmental impacts. 

Compare using methane from natural gas with using methane from methane hydrates in terms of environmental impact and efficiency. You will need to do some research to find out extraction methods for each source of methane. 

Safe, S. Hutzinger, O. Hill, T. A. (Eds.) Polchlorinated Dibenzo-p-Dioxins and -Furans (PCDDs/PCDFs). Sources and Environmental Impact, Epidemiology, Mechanisms of Action, Health Risks, Environmental Toxin Series 3, Safe, S. Hutzinger, O. (Eds.) Springer, Berlin, 1990. 

Konietzko, H. Chlorinated ethanes sources, distribution, environmental impact, and health effects, in Hazard Assessment of Chemicals, Volume 3, Saxena, J., Ed. (New York Academic Press, 1984), pp. 401-448. 

Surveys of Environmental Impacts. Field survey methods focus on assessing changes in the condition of entire populations and ecological community functions (e.g., pest species proliferation, species diversity, litter decomposition rate, changes in the rate of primary production). These methods under certain circumstances may relate effects to specific pollutant sources, but most frequently they are used to indicate that a problem does exist. A current application of survey methods being developed emphasizes identification of indigenous species to serve as surrogates for a portion of the ecosystem. 

J. Santodonato, and P.H. Howard, Azaarenes Sources, Distribution, Environmental Impact and Health Effects, in Hazard Assessment of Chemicals Current Developments, J.Saxena, and P. Fisher (E[Pg.651]

The quantitative assessment of environmental impacts can be made using life-cycle assessment (LCA) methodology, which accounts for both inputs and emissions. LCA can be used to identify the major environmental impact categories and the sources of those impacts within a chemical processing plant. LCA can also be used to identify the major contributions to environmental impact within a product s life cycle. Impact scores derived from LCA can be used along with economic assessment scores and social indicators to provide indicators of overall sustainability of processes and products. Economic assessments are often limited through failure to account for all internal costs and especially the external costs associated with waste. 

Principal structures of aminic stabilizers, their involvement in individual degradation processes of polymers, behaviour in mixtures with other polymer additives and an outline of environmental impacts due to the amines are included. The most relevant literature sources published by the first quarter of 1994 are reported. Some earlier data has to be mentioned as a reminder of the original ideas and to improve the interpretation of results. Where relevant, recent comprehensive reviews are cited. Principal types of commercial stabilizers are included in Appendix. 

Meyers, R. A., ed. 1998. Encyclopedia of Environmental Analysis and Remediation. (8 vols.) New York John Wiley Sons. The preface categorizes this eight-volume encyclopedia as a professional level compendium of all aspects of the environment. Emphasis is on sampling, analysis, and remediation, but the work also includes discussions of pollution sources, transport, regulations, and health effects. There are about 280 articles, many including tables, figures, equipment procedures, and standards. Information to assist in preparation of parts of environmental impact statements and air permitting documents is also included. 

The two key elements of an LCA of the fuel cell system are the assessment of the entire life cycle of the fuel cell system and the assessment of a variety of environmental impacts because of it. The first step is the goal and scope definition, in which the system, the intended application, the data sources, and system boimdaries are described and the functional unit, that is, the reference of all related inputs and outputs, is defined. The criteria for selecting input and output flows or processes have to be specified, hi this step, the data quality requirements time-related and geographical coverage the consistency, representativity, and imcertainty of the data and the critical review procedure have to be described. 

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