Plant siting and layout

The proper location of a plant is as important to its success as the selection of a process. Not only must many tangible factors such as labor supply and raw material sources be carefully considered, but also a number of intangible factors, w hich are more difficult to evaluate. The selection of a plant site must be based on a very detailed study in which all factors are weighed as carefully as possible. Such a study often requires a substantial outlay of capital. 

For many processes, one or more predominant factors effectively minimize the number of possibilities for plant location. Raw material and transportation costs may be such that a plant must be located near a source. Thus, only the sites near to sources of raw material need be studied and these may be few in number. Similarly, labor requirements may be hear y enough to eliminate cities below a certain size. These and other factors serve as effective screening agents that save both time and money. 

Important factors to be considered in the study of areas and sites for plant location include raw materials, transportation, process water, waste disposal, fuel and power, and weather. These are discussed individually. 

Quick-opeiiiiig valve Seir-draiiiiiig valve 

DESCRIPnON Blow-off valves Varec vent valve 

Atwood Morrill straight tliru relief valve on exliaust steam ( VE) 

Quiek-opeiiiug valve Scll-draimng valve 

Chain operated valve Reel valve Quench valve Needle or V-port 

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Some important factors regarding a safe plant can be better understood if the reader is familiar with such process equipment as reactors (Section 5.2), mass transfer units (Section 5.3), heat exchanges (Section 5.4), ancillary equipment (Section 5.5), environmental equipment (Section 5.6), and utilities (Section 5.7). Protective equipment is reviewed in Section 5.8. Process diagrams, which illustrate the various possible arrangements of plant equipment, valves, piping, and control systems, are presented in Section 5.9. Plant siting and layout are discussed in Section 5.10 - this last section illustrates the factors that can contribute to proper plant operation. 

Plant siting and layout are important for the safety of the workers in the plant as well as the surrounding comniunities. A proper plant layout can save both lives and dollars. 

List the important factors to be considered in plant siting and layout. 

The first step in minimizing accidents in a chemical phuit is to evaluate the facility for potential fires, explosions, and vulnerability to other liazards, particularly those of a chemical miture. This calls for a detailed study of plant site and layout, materials, processes, operations, equipment, and training, plus an effective loss prevention program. The technical nature of industry requires detailed data and a broad range of experience. Tliis complex task, today becoming the most important in plant design, is facilitated by the safety codes, standiu ds, and practice information available. The technical approach to evaluating die consequences of hazards is discussed later in tliis cliapter and in Part V (Chapters 20 and 21). 

The minimiziiig/prevendon of accidents in a chemical plant calls for a detailed study of plant site and layout, materials, processes, operations, equipment, and training, plus an effective loss prevention program. 

Topics include inherent safety in a process, considerations lor safer plant siting and layout, Improved equipment and piping design, and active and passive protective systems... 

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