Equipment space requirements

The Dow indexes are useful for determining equipment spacing requirements. The F EI uses an empirical correlation based entirely on the F EI value to estimate the radius of exposure. It is assumed that any equipment located outside this distance would not be damaged by a fire or explosion. The CEI estimates the hazard distance for chemical exposure based on the emergency response planning guideline (ERPG) values for the particular material released. 

The intent of this book Is to help train, on an accelerated basis, the young engineers and technicians entering the field of process plant layout and piping design. It also updates equipment spacing requirements and addresses the latest feature of elearonic data transfer for the experienced layout designer. 

Some industrial processes produce predorninately latent air conditioning loads. Others dictate very low humidities and when the dew point falls below 0°C, free2ing becomes a major concern. Dehydration equipment, using soHd sorbents such as siUca gel and activated alurnina, or Hquid sorbents such as lithium chloride brine and triethylene glycol, may be used. The process is exothermic and may require cooling the exiting air stream to meet space requirements. Heat is also required for reactivation of the sorbent material. 

Comparing two or more complex alternatives is more difficult than examining equipment capacity or first cost. Characteristics of alternatives should be weighted for relative importance and measured on a common scale to aEow proper evaluation. Many characteristics such as first cost, capacity, space requirement, and annual energy use can be measured objectively and used for system comparisons. Experience has shown that items such as maintenance expense, component life, and downtime can also be rehably estimated. Other factors, eg, system maintainabEity, flexibEity, and comfort, are more arbitrary. 

Ground area and. space requirement.s. Comparisons of the overall space requirements for plants using air cooling versus water cooling are not consistent. Some air-cooled units are installed above other equipment—pipe racks, shell-and-tube exchangers, etc. Some plants avoid such inst ations because of safety considerations, as discussed later. 

Flocculation units should have multiple compartments and should be equipped with adjustable speed mechanical stirring devices to permit meeting changed conditions. In spite of simplicity and low maintenance, non-mechanical, baffled basins are undesirable because of inflexibility, high head losses, and large space requirements. Mechanical flocculators may consist of rotary, horizontal-shaft reel units as shown in Figure 9. 

Space requirements The footprint (m-) or volume tor a given item of equipment. 

To start a detailed planning study, space requirements must be known for various products, by-products, and r iw materials, as well as for process equipment. A starting or reference point, together with a directional schematic flow pattern, will enable the design engineers to make a trial plot plan, as e.xplained below, A number of such studies will be required before a suitable plot and elevation plan can be chosen. 

When planning new installations, manufacturers catalogues may be the only information source of equipment data, but they rarely indicate the space needed outside the equipment outline. This requires careful consideration from an experienced facility planner to establish realistic space requirements. 

When it comes to laboratory storage, it is safe to say that the space required is at least twice what a planner would estimate. Samples, reagents, and spare equipment will pile up at an alarming rate. To this should be added the fact that some items will have to be stored under controlled conditions and that valuable items will need to be kept in locked storage. Flammables, even in moderate amounts, need special storage. Since regulations vary from one area to another, this matter should be discussed with local fire department officials. 

Type of equipment Minimum particle size w Minimum loading (mg/m3) Approx. efficiency (%) Typical gas velocity (m/s) Maximum capacity (m3/s) Gas pressure drop (mm H2O) Liquid rate (m3/103 m3 gas) Space required (relative)... 

Laboratory algal assays for monitoring the toxicity of an allelochemical are very useful, due to the ease and rapidity with which the organism can be cultured and their responses measured. They also require less equipment, space and time of the researcher. 

The spacing recommendations for process layout have been presented in literature as matrixes and lists of the typical minimum distances between different process items (Industrial Risk Insurers (1991) Bausbacher and Hunt (1993) Prugh (1982)). A suitable distance to another process item depends mostly on the safety properties of the process items. The clearance required for maintenance and access determine usually shorter spacings compared to safety clearances. In some references access and maintenance clearances are given separately. Therefore it can be assumed that the average of the recommended equipment spacings is mostly related to the general unsafety of a specific process item. 

Layout spacings are also affected by other factors than safety. The space requirements of maintenance, repair works and proper performing of process operations has to be included into the process layout. Proper spacing around equipment is required to allow easy operation. Enough room should be provided for pipes, supports and foundations as well. 

Smoke detectors should be located and spaced to ensure prompt detection under incipient fire conditions. Spacing requirements should consider the type of detector used, manufacturer recommendations, geometry of the protected area, and effects of air handling equipment. See NFPA 72 for more information on spacing. 

GAC equipment generally has small space requirements and often can be used as mobile units. 

When allocating the areas for production, attention must be given to the space requirements of the equipment—not only the footprint of the equipment, but also the working area. This includes the ancillary equipment, i.e., controls, materials in-process, as well as operator working areas. In other words, there should be enough space for the operator to bring in the material to be processed, operate the machinery, and record the process in a batch record. 

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