Environmental life cycle analysis

ENVIRONMENTAL LIFE-CYCLE ANALYSIS OF ALTERNATIVE BUILDING MATERIALS... 

Environmental Life-cycle Analysis of Altemative Building Materials... 

Capital, operating, and environmental controls, and some life-cycle analysis (Total Systems Approach)... 

Global environmental questions have increased in significance during the last few years. A life-cycle analysis (LCA) analyzes the environmental effect with reference to ecological effects, health effects, and consumption of resources. 

Life-cycle analysis of a filter shows that operation often corresponds to 70% to 80% of the filter s total environmental load and is absolutely decisive as regards environmental effect. Raw material, refining, manufacturing, and transports correspond to about 20% to 30%, while the used filter contributes at most 1%. Filters of plastic or other inflammable material can render 10 kWh to 30 kWh energy when burned, which correspondingly reduces the total environmental load from 0.5% to 1%. On the other hand, if the pressure loss in the filter is reduced by 10 Pa, the environmental load is reduced by 125 kW h per year, or approximately 5% decrease in total environmental load. Filters in industrial applications can have quite different figures. 

The ISO 14000 series of environmental standards and their implications for the plastics industry are discussed. Aspects of ecolabelling and life cycle analysis and different options for recycling and waste disposal are examined. 

ICI Acrylics believes that greater cooperation between companies and a revised approach to life cycle analysis are the keys to the industry s future environmental sustainability. The company has invested over 2m pounds sterling in an on-going monomer recovery project, which encompasses a joint research programme with Mitsubishi Rayon. The project focuses on increasing the efficiency of acrylic depolymerisation and overcoming technical issues such as its use in recycling flame retardant acrylics. ICI ACRYLICS... 

A life cycle assessment (LCA), also known as life cycle analysis, of a product or process begins with an inventory of the energy and environmental flows associated with a product from "cradle to grave" and provides information on the raw materials used from the environment, energy resources consumed, and air, water, and solid waste emissions generated. GHGs and other wastes, sinks, and emissions may then be assessed (Sheehan et ah, 1998). The net GHG emissions calculated from an LCA are usually reported per imit of product or as the carbon footprint. 

In the past decades, polymer materials have been continuously replacing more traditional materials such as paper, metal, glass, stone, wood, natural fibres and natural rubber in the fields of clothing industry, E E components, automotive materials, aeronautics, leisure, food packaging, sports goods, etc. Without the existence of suitable polymer materials progress in many of these areas would have been limited. Polymer materials are appreciated for their chemical, physical and economical qualities including low production cost, safety aspects and low environmental impact (cf. life-cycle analysis). 

A broader and more detailed evaluation can be done by performing a Life Cycle Analysis (LCA). The central idea of a LCA is that the environmental effects during the entire life cycle of a process are quantified. These environmental effects are caused by the use of fossil fuels for heating and production of electricity, the use of non-renewable raw materials for the production of materials and chemicals, and the emissions of pollutants to air, water and soil. These environmental effects can be subdivided further in various levels of detail. The five major effects mentioned are derived from the more general effects considered in the framework of the LCA. Based on the environmental sustainability of each of the complete treatment scenarios considered as technically feasible, a ranking according environmental... 

Well-to-wheel analysis is a specific form of life-cycle analysis (LCA). In contrast to WTW analysis, LCA typically also takes factors other than global GHG emissions of a product or an energy carrier into consideration (such as air pollutants), including provision of all construction materials for the necessary processing plants and, furthermore, plant decommissioning. The full detail of a general LCA analysis is not needed at the level of policy discussion to reach a broad consensus on alternative fuels or drive systems. As a subset of WTW analysis, well-to-tank (WTT) analysis is often used to separate environmental or economic effects of fuel supplies and drive systems. 

In polymer applications derivatives of oils and fats, such as epoxides, polyols and dimerizations products based on unsaturated fatty acids, are used as plastic additives or components for composites or polymers like polyamides and polyurethanes. In the lubricant sector oleochemically-based fatty acid esters have proved to be powerful alternatives to conventional mineral oil products. For home and personal care applications a wide range of products, such as surfactants, emulsifiers, emollients and waxes, based on vegetable oil derivatives has provided extraordinary performance benefits to the end-customer. Selected products, such as the anionic surfactant fatty alcohol sulfate have been investigated thoroughly with regard to their environmental impact compared with petrochemical based products by life-cycle analysis. Other product examples include carbohydrate-based surfactants as well as oleochemical based emulsifiers, waxes and emollients. 

Since FAS can be produced either from vegetable oil based or petrochemical-based fatty alcohol (Fig. 4.9), both types have been evaluated in a life-cycle analysis with a positive overall result for the natural based product. With vegetable-based fatty alcohol sulfate, the analysis starts with the harvesting of the oil fruits (palm kernels or coconuts) and their processing to isolate the desired plant oil. Subsequent transesterification and hydrogenation of the methyl ester intermediates lead to the fatty alcohols, which are finally sulfated to produce the desired product. Based on this analysis the environmental impact of vegetable oil based fatty alcohol sulfate compared with the petrochemical based product is as follows ... 

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