393-404 Inglese

Environmental economics, which analyses the links between economic activity and environmental systems, has hypothesized that a relation which may be described as an ‘inverted U’ exists between environmental quality/pollution and pro capite income variables (Kuznets hypothesis; Kuznets, 1955). According to this hypothesis, when income begins to grow, starting from a low level, the environmental impact first increases to a maximum corresponding to a certain income value, and then starts decreasing. In substance, the dichotomy between economic growth and environmental protection is said to exist only at low income levels and instead, at higher levels, to become a synergy. It would seem, therefore, that by increasing income levels, a future of sustainability may be envisaged. This hypothesis is, moreover, a plausible one; as with economic growth, environmental externalities become more and more evident and induce the competent authorities safeguarding public environmental assets to intervene with increasingly restrictive regulations and provisions. Even though the supplementary investments to be made and the additional operating costs penalize, to a certain extent, the sector that sustains them, at the same time a fresh demand for goods and services is generated which contributes towards overall economic growth. The historical evolution of the refineries – and more generally of the energy sector – is a good demonstration of this theory. Indeed, refineries are set up in the first phase of a country’s development, helping it to grow both economically and socially, and continuing this support throughout its post-industrial development phases. Many refineries currently operating are more than 50 years old, and are expected to operate for a long time to come. Although accurate environmental auditing has only been introduced in the last few decades, historical experience allows it to be stated that the environmental impact of refineries, for the same output, has systematically diminished, thanks to management based on continuous improvement. The environmental impacts of a refinery are both direct and indirect; in this chapter only the former are considered. Indirect impacts are in fact connected with the final use of petroleum products and pertain not so much to the environmental management of a refinery, as to its overall configuration and to the integration of the various processes that determine the ecological quality of the products. Direct impacts, on the other hand, are generated by processing units and by the activities carried out within the refinery. Refineries are highly complex industrial plants containing numerous integrated process units, with a vast range of possible configurations. They differ in size, complexity of the processes used, flexibility of the loads that can be treated, and typology and quality of end-products. Furthermore, they are diversified in terms of production strategy (linked to market demand), age and historical evolution, and lastly the availability of infrastructure and services for the local environment. Considering the complexity of the processes applied to the oil in order to attain the formulation and distribution of the derived products, it is not surprising that a refinery covers a large part of the spectrum of possible environmental impacts. The map of impacts relating to a refinery is shown in Table 1, broken down into the basic environmental matrixes: air, water and soil. These impacts occur at various scales: local, with effects on the work place and on the surrounding territory and community; regional, for example in the case of acid rain, photochemical smog and waste disposal; and global, with special reference to the emission of greenhouse gases. To mitigate these