Overview of typical system requirements

This chapter provides an overview of the present situation regarding BEWS. The technical, financial and biological requirements of successful BEWS systems are discussed. Suitable organisms are identified and the needs for quality assurance and validation are highlighted. Some representative early warning systems that are successfully used in environmental monitoring are presented. Illustrations of typical field applications that focus on the requirements of environmental monitoring in the context of the WFD are included as case studies. 

Hence, to model a chemical plant precisely requires a lot of effort. This effort is typically expended when a new plant is planned. However, such a precise process model is not necessary or useful for other purposes. In short-term control of chemical production plants, so-called prediction control models are used which focus on the measurement of system responses to certain changes of control variables on an empirical basis. These models use basic relations of the theoretical models introduced above. The next subsection outlines a brief overview of such models. 

Notice the layout of a typical refinery (Figure 1). Of course, this is extremely simplified, but it will serve to show the complexity of a modern refinery. This chapter goes through the major units with a description of the system, typical metals of construction, and problem areas that may require chemical cleaning. Please remember that all refineries are not alike they will actually vary quite substantially. A very broad overview of these types of units and some of the fouling deposits that may be found in them is presented. 

The remainder of the paper is structured as follows Section 2 gives an overview of relevant parts of the standards VDE 0832 and EN 50556, respectively. Section 3 presents a hazard analysis using HAZOP analysis. Section 4, in turn, introduces the embedded system platform architecture derived from the safety and domain specific requirements. In addition. Section 5 proves the architecture by going through a typical use-case. The main steps within the architecture are highlighted. Finally, Section 6 concludes by summarizing the key facts of the work carried out. 

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