Layout of plant

Interaction tests should be made on all unprotected structures in the vicinity of a proposed cathodic protection installation, and should be repeated annually or at some other suitable interval to ensure that alterations in the layout of plant or in the electrical conditions are taken into account. It is most convenient if the tests on all unprotected pipes or cables are made at the same time, the potential measurements being synchronised with the regular switching on and off of the protection current. It may then be convenient to continue with further tests to confirm that any remedial measures applied to one installation do not adversely affect other installations. 

Many of the problems involved in maintenance are often caused by a lack of thoroughly evaluating the original design and layout of plant and equipment. Sufficient space for maintenance work on equipment and facilities must be provided in the plant layout, and the engineer needs to consider maintenance and its safety requirements when making decisions on equipment. 

The basic layout of plants for the manufacture of biopharmaceuticals is similar. A production train also consists of feed tanks, a reactor or fermentor, and workup equipment. In most cases, all apparatus is installed in the wet section. The main difference lies in the substantial and demanding provisions that have to be taken to avoid contamination in any part of the production unit. The process water or water for injection has to fulfill particularly demanding requirements. 

Physical separation and layout of plant components REFERENCES ANNEX SAFETY FUNCTIONS FOR BWRs, PWRs AND PRESSURE TUBE REACTORS GLOSSARY... 

The layout of plant and the design of individual machines should allow adequate access for cleaning. Where high levels of cleanliness are essential, as in the food and pharmaceutical industries, equipment should not have acute internal comers or crannies that can harbour dirt. If washing down is necessary, the electrical equipment should be either encapsulated or protected to the appropriate IP level. 

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. 

Fig. 11. Layout of a2o dye manufacturing plant. 1, storage tanks for liquid starting materials 2, storage dmms for solid starting materials 3, dia2oti2ation vessel 4, coupling component vessel 5, ice machine 6, coupling vessel 7, isolation vessel 8, filter presses 9, filtrate to waste liquor treatment plant 10,...

The design and layout of the physical facihties that make up the processing-plant flow sheet are an important aspect in the implementation and successful operation of such systems. Important factors that must be considered in the design and layout of such systems include (1) process performance efficiency, (2) rehability and flexibihty, (3) ease and economy of operation, (4) aesthetics, and (5) environmental controls. 

Landfill-operation plan. The layout of the site and the development of a workable operating schedule are the main features of a landfill-operation plan. In planning the layout of a landfill site, the location of the following must be determined (1) access roads (2) equipment shelters (3) scales, if used (4) storage sites for special wastes (5) topsoil-stockpile sites (6) landfill areas and (7) plantings. 

Unit layout as installed is the next step of preparation. This may take some effort if analysts have not been involvea with the unit prior to the plant-performance analysis. The equipment in the plant should correspond to that shown on the PFDs and P IDs. Wmere differences are found, analysts must seek explanations. While a hne-by-line trace is not required, details of the equipment installation and condition must be understood. It is particularly useful to correlate the sample and measurement locations and the bypasses shown on the P IDs to those ac tuaUy piped in the unit. Gas vents and liquid (particularly water-phase) discharges may have been added to the unit based on operating experience out not shown on the P IDs. While these flows may ultimately be small within the context of plant-performance an ysis, they may have sufficient impact to alter conclusions regarding trace component flows, particularly those that have a tendency to build in a process. 

Figure A13.12 Layout of a typical effluent-treatment plant...

Figure 22.19 General layout of a power plant, station grounding grid, and switchyard grounding grid etc.

The failure took place in a large water-tube boiler used for generating steam in a chemical plant. The layout of the boiler is shown in Fig. 13.1. At the bottom of the boiler is a cylindrical pressure vessel - the mud drum - which contains water and sediments. At the top of the boiler is the steam drum, which contains water and steam. The two drums are connected by 200 tubes through which the water circulates. The tubes are heated from the outside by the flue gases from a coal-fired furnace. The water in the "hot" tubes moves upwards from the mud drum to the steam drum, and the water in the "cool" tubes moves downwards from the steam drum to the mud drum. A convection circuit is therefore set up where water circulates around the boiler and picks up heat in the process. The water tubes are 10 m long, have an outside diameter of 100 mm and are 5 mm thick in the wall. They are made from a steel of composition Fe-0.18% C, 0.45% Mn, 0.20% Si. The boiler operates with a working pressure of 50 bar and a water temperature of 264°C. 

Process Conceptual Design Equipment selection and sizing Inventory of process Single vs. Multiple trains Utility requirements Overdesign and flexibility Recycles and buffer capacities Instrumentation and control Location of plant Preliminary plant layout Materials of construction As above plus equipment suppliers data, raw materials data, company design procedures and requirements... 

Figure 1. Layout of the solvent phase polypropylene plant with the leak location.

Representational layout of control panels. Where the physical location of items is important, for example, area displays in fire control systems, the layout of the displays on a control panel should reflect the geographical layout of the plant. In other cases a functional arrangement of the elements of the process plant will be appropriate, for example, when monitoring the status of the system via an alarm panel. 

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. 

The ignition sources described above cannot be eliminated, but tliey can be controlled by careful layout of tlie plant, proper design and maintenance of equipment, and tlie use of trip systems. 

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. 

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