Plant layout techniques

A detailed account of plant layout techniques cannot be given in this short section. A fuller discussion can be found in the book edited by Mecklenburgh (1985) and in articles by Kern (1977, 1978), Meissner and Shelton (1992), Brandt et al. (1992), and Russo and Tortorella (1992). 

Hazard analysis (HAZAN) is a quantitative way of assessing the likelihood of failure. Other names associated with this technique are risk analysis, quantitative risk assessment (QRA), and probability risk assessment (PRA). Keltz [44] expressed the view that HAZAN is a selective technique while HAZOP can be readily applied to new design and major modification. Some limitations of HAZOP are its inability to detect every weakness in design such as in plant layout, or miss hazards due to leaks on lines that pass through or close to a unit but cany material that is not used on that unit. In any case, hazards should... 

Historically, modeling techniques have had little impact on the problem of designing plant layouts. This has been for two reasons. First, the calculations are difficult, and second, practical constraints and considerations essential to the decision are often ignored. 

One of the principal tasks facing the manager responsible for implementing a new plant layout is the planning and scheduling of the many activities involved in the project. Modem computerized systems have evolved into easy-to-use tools that avoid the need for a detailed technical knowledge of planning techniques. 

Plant Layout, Location, Design and Construction. For information on the special techniques required in the loading and fabrication of expls pertinent to ammo plant layout and design, see the entry under that title in Vol 7, L46-L to L57-L For what has been done to accomplish modernization of munitions plants now extant, see Modernization Engineering Project for US Army,Ammunition Plants1 in this Vol, M.147-L to Ml48-R. The problem of pollution created by ammo plants is examined in an article under this topic in this Vol... 

The plant engineer may be called upon to design a new facility or the flow and layout of an existing facility. With the use of CAD and computerized layout techniques such as CORELAP, multiple options can be evaluated qualitatively and quantitatively to select the optimum solution. Performance of the selected solution can be evaluated further using techniques of simulation and optimization discussed in Chapters 93-102. 

In 1973, Richard Muther published a method of analyzing the interrelationships of activities within industrial plants, and the method allows a high degree of detail to be examined. The method proposed here is similar in that a relationship grid is constructed, but this technique employs the power of the modern desktop computer to rapidly examine alternative layouts to obtain best solutions. 

Design techniques for an inherently safer plant include improved layouts, inventory reduction, and process improvements. 

A HAZOP study is a very useful technique that may lead to a more reliable and safer process. Whether it is applied at preliminary design stages or to the detailed layout of an existing plant, its benefits can be invaluable. It reduces the possibility of accidents for the process involved, improves on-stream availability of the process, can lead to a better understanding of the process and possible malfunctions, and provides training for the evaluation of any process. Finally, it is also a way of optimizing a process and providing a reliable and cost-effective system. 

Nevertheless, each particular material from a plant species may require some modification of described methods and usual techniques. The methods are described critically, with hints as to their limitations. In general it will be possible to adapt the methods described to the specific needs of the users of this series, but nevertheless references have been made to the original papers and authors. While the editors have worked to plan in this New Series and made efforts to ensure that the aims and general layout of the contributions are within the general guidelines indicated above, we have tried not to interfere too much with the personal style of each author. 

Techniques that take account of human factors, such as task analysis, should be used to develop safe, reliable and effective OPs in which account is taken of the layout of the control room, the general design of the plant, and staffing arrangements and operating experience at the plant concerned. 

---