Environmental performance index

Figure 5.1 Scheme of construction of an Environmental Performance Index. Source Yale Center for Environmental Law and Policy [20]. 

The EPS system was initially developed to be used within the product development process as a tool to help assess the environmental performance of products. The system is based on LCA (Life Cycle Assessment) methodology and uses inventory data (kg of substance A), characterization factors (impact/kg of substance X) and weighting factors (cost/impacts) to calculate the external costs or values of a product. By multiplying the characterization factor with the weighting factor, an impact index is obtained (cost/kg of substance X) which describe the cost/values related to the emission per use of a kg of a certain substance. 

In the case study, the indexes involved are /gen and environmental performance of a process also relates to its emission of PEL Therefore, in the WAR algorithm, the output rate of PEI, 7out, and... 

The reaction system involved in the case studied is a kind of relatively complex van de vusse reaction, nevertheless the reaction system in real manufacturing process may involve more reaction types and, therefore, is more complex than that one. One can, however, simulate the change of environmental indexes within a reactor by combining traditional reactor mathematical model with the PEI balance, and may also discover the effects of reaction conditions and engineering factors on environmental performance by PEI rate-law expression and/or combinations it with other reaction rate equations as well as other related equations in reactor mathematical models. 

After a process flowsheet has been established, it is appropriate for a detailed environmental impact evaluation to be performed. The end result of the impact evaluation will be a set of environmental metrics (indexes) representing the major environmental impacts or risks of the entire process. A number of indexes are needed to account for potential damage to human health and to several important environmental compartments. 

Zhao et al. describe the concepts and mathematical foundations for PARIS II software that designs solvent mixtures based on optimal solvent properties. The solvent property categories include performance requirements and environmental requirements (a VOC index and an environmental impacts index), and are based on general, dynamic, and equilibrium properties. The chapter by Nelson contains... 

The environmental impacts of both the solvent to be replaced and the replacement solvent are considered using two indexes an air index and an overall environmental index. Since the object here is to formulate substitute solvents that have better environmental performance, the indexes for the solvent to be replaced are not matched but are rather treated as an upper bound on the indexes of the acceptable replacement. This insures that the replacement solvent is environmentally better than the original solvent as measured by the indexes. The inherent toxic effects of the solvent and the toxic effects due to volatile organic emissions are considered separately because, when chemicals are mixed, their volatility changes due to the non-idealities in the mixture. Therefore, a chemical that has low risk by inhalation due to low volatility in pure form can have a much higher volatility and a much higher risk when mixed with other chemicals. The air index,... 

In the last twenty years, various non-deterministic methods have been developed to deal with optimum design under environmental uncertainties. These methods can be classified into two main branches, namely reliability-based methods and robust-based methods. The reliability methods, based on the known probabiUty distribution of the random parameters, estimate the probability distribution of the system s response, and are predominantly used for risk analysis by computing the probability of system failure. However, variation is not minimized in reliability approaches (Siddall, 1984) because they concentrate on rare events at the tail of the probability distribution (Doltsinis and Kang, 2004). The robust design methods are commonly based on multiobjective minimization problems. The are commonly indicated as Multiple Objective Robust Optimization (MORO) and find a set of optimal solutions that optimise a performance index in terms of mean value and, at the same time, minimize its resulting dispersion due to input parameters uncertainty. The final solution is less sensitive to the parameters variation but eventually maintains feasibility with regards probabilistic constraints. This is achieved by the optimization of the design vector in order to make the performance minimally sensitive to the various causes of variation. 

An expansion of the Eco Index (an internal self-assessment tool created by the outdoor apparel industry) and Nike s Apparel Environmental Design Tool, the Higg Index aims to aggregate information on the environmental performance of products from major apparel brands. The Index considers performance across the full life-cycle of a product, including impacts fi om input materials, manufacturing, packaging, transportation, use, and end-of-life. ... 

The focus of the Sustainable Apparel Coalition is the Higg Index that measures the environmental performance of apparel products. Future versions will include footwear products and measure social performance. 

The Higg Index 1.0 is a tool to help organizations standardize how they measure and evaluate environmental performance of apparel products across the supply chain at the brand, product and facility levels. It is ... 

The Higg Index 1.0 was developed for apparel products and environmental performance however, future releases of the Higg Index will expand the scope to include footwear products and social and labor impact areas. 

The biocatalytic reduction step B in synthetic route B demands more raw materials (mass index S , see equation (5.1)) and generates more waste (environmental factor , see equation (5.2)) as compared to reduction step C (Figure 5.1). Solvents used to perform the extraction of the product from the aqueous phase in reduction step B are denoted as auxiliaries in Figure 5.1. These solvents and the aqueous phase dominate the mass balances as well as the environmental scores in Figure 5.2 (M4, M8). 

Oilfields in the North Sea provide some of the harshest environments for polymers, coupled with a requirement for reliability. Many environmental tests have therefore been performed to demonstrate the fitness-for-purpose of the materials and the products before they are put into service. Of recent examples [33-35], a complete test rig has been set up to test 250-300 mm diameter pipes, made of steel with a polypropylene jacket for thermal insulation and corrosion protection, with a design temperature of 140 °C, internal pressures of up to 50 MPa (500 bar) and a water depth of 350 m (external pressure 3.5 MPa or 35 bar). In the test rig the oil filled pipes are maintained at 140 °C in constantly renewed sea water at a pressure of 30 bar. Tests last for 3 years and after 2 years there have been no significant changes in melt flow index or mechanical properties. A separate programme was established for the selection of materials for the internal sheath of pipelines, whose purpose is to contain the oil and protect the main steel armour windings. Environmental ageing was performed first (immersion in oil, sea water and acid) and followed by mechanical tests as well as specialised tests (rapid gas decompression, methane permeability) related to the application. Creep was measured separately. 

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