Safety layout

The development section serves as an intermediary between laboratory and industrial scale and operates the pilot plant. A dkect transfer from the laboratory to industrial-scale processes is stiH practiced at some small fine chemicals manufacturers, but is not recommended because of the inherent safety, environmental, and economic risks. Both equipment and plant layout of the pilot plant mirror those of an industrial multipurpose plant, except for the size (typically 100 to 2500 L) of reaction vessels and the degree of process automation. 

The most important hazard ia the manufacturiag of xanthates is the use of carbon disulfide (qv) because of its low flash poiat, ignition temperature, and its toxicity. A report on the manufacture of sodium ethyl xanthate at Keimecott Nevada Mines Division discusses the various safety problems and the design of a faciUty (81). A plant layout and a description of the reagent preparations are also given. 

SHEL (Safety Healthy Environmental and Loss Prevention Reviews) These reviews are performed during design. The purpose of the reviews is to have an outsider s evaluation of the process and layout from safety, industrial hygiene, environmental, and loss prevention points of view. It is often desirable to combine these reviews to improve the efficiency of the use of time for the reviewers. 

Safety issues in batch reaction systems relating to equipment configuration and layout are presented in Table 3. This table is meant to be illustrative but not comprehensive. A few key issues are presented below. 

Tisted below are safety practices aimed at minimizing hazards due to equipment configuration and layout. 

Faetory layout has a signifieant bearing on safety. Relevant eonsiderations inelude ... 

Identify the major safety hazards and eliminate them, if possible Locate critical areas on the flow diagrams and layout drawings... 

Study of the Plot Plan Layout From the plot plan layout the number of safety valves in different process areas, the set pressures of safety valves, individual relieving loads of safety valves, relieving temperature of vapors, the nature of vapors (i.e., whether corrosive, condensable, or dry) are noted. 

Containment design details - basic structure, major contents (beat structures), internal safety systems performance data, special features, reactor cavity/sump details, layout elevations and floor plans, fnateriais specifications, design limits, etc. 

A deactivated butane pressurized storage facility with two 750 m and two 1,6(X) m spheres was considered for partial activation of the two smaller spheres. A safety review showed that aspects of the facility did not comfily with with current standards of PETROBRAS regarding layout and separation. A PSA was performed with the following objectives ... 

It should be obvious from this discussion that the technique of creating a hazard tree is somewhat subjective. Different evaluators will likely classify conditions and sources differently and may carry the analysis lo further levels of sources. However, the conclusions reached concerning building design, maintenance, layout of traffic patterns, lighting, ok., should be the same. The purpose of developing the hazard tree is to l ocus attention and help the evaluator identify all aspects that must be considered in reviewing overall levels of safety. 

The basic blocks with which to build an arrangement for plot plans are often used in the unit area concept. This method of planning is particularly well adapted to large plant layouts. Unit areas are often delineated by means of distinct process phases and operational procedures by the presence or absence of contamination and by safety requirements. Thus, the determination of the shape and extent of a unit area and the interrelationships of each area in a... 

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. 

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 most logical suming point in tlie safety design approach is to select a site where tlie number of undesirable weather and topograpltic conditions is limited. Adequate utilities and support systems plus fire protection service arc also required for a safe eiiviromnent. Chapter 5 presented a detailed account of phuit site selection and layout. These features will now be considered from a safety point of view. The following guidelines should be observed in dctcrniining a site tliat is favorable for tlie efficient tuid economical operation of the process. 

Occupational Safety and Health Administration regulations as they relate to (a) safety of design related to injury to personnel (includes such matters as latest vessel design [53], noise level from operating equipment, etc., [20, 21, 22, 23, 24, 25, 26, 27, 28]. (b) safety of the plant layout emdronment which might influence the safety of the plant facilities. 

Energy Efficient (EE) Motor Designs, 628 NEMA Design Classifications, 630 Classification According to Size, 630 Hazard Classifications Fire and Explosion, 631 Electrical Classification for Safety in Plant Layout, 647 Motor Enclosures, 649 ... 

It might be assumed that if an examination of the plant layout is being carried out, the future plans, as they affect the site layout, will be known. This is not always the case therefore, management should be questioned at the beginning of the project. Particular attention should be paid to hazardous substances that may be used on the site, and the health and safety document should be consulted. 

A laboratory may come in any size or shape. It may be a room in an industrial plant, a wing of a hospital, or a whole building on a college campus. All of these present similar problems and decisions at the planning stage. Where should the laboratory be located How much space is required Will a proposed layout contribute to smooth traffic flow What utilities are needed What safety factors should be built in These are just some of the major questions planners must address. 

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