Factor materials

The procedure begins by using a material factor that is a function only of the physical properties of the chemical in use. The more hazardous the material, the higher the material factor. A table containing factors for common materials is provided with the Index. Additionally, a procedure is detailed for determining the material factor for unlisted materials. 

EinaHy, the penalties are factored into the original material factor to result in a fire and explosion index value. The higher this value, the higher the degree of hazard. 

The material factor A contains the material parameters and is a description of the number of recoil atoms that can escape from the soUd. In one description (31) (eq. 18), N is the atomic density of target atoms and is the surface binding energy. 

Numerous observations of the effect in ionic crystals were carried out by Mineev and Ivanov in the Soviet Union [76M01]. This is a class of crystals in which a number of materials factors can be confidently varied. By choice of crystallographic orientation, various slip directions can be invoked. By choice of various crystals other physical factors such as dielectric constant, ionic radius, and an electronic factor thought to be representative of dielec-... 

In contrast, because of the spatially variable (inhomogeneous) nature of material in a composite stiffener, the bending stiffness cannot be separated into a material factor times a geometric term as in Equation (7.6). Instead, the composite stiffener bending stiffness is... 

Factors re.sponsible for the occurrence of scale-up effects can be either material factors or size/shape factors. In addition, differences in the mode of operation (batch or semibatch reactor in the laboratory and continuous reactor on the full scale), or the type of equipment (e.g. stirred-tank reactor in the laboratory and packed- or plate- column reactor in commercial unit) can be causes of unexpected scale-up effects. A simple misuse of available tools and information also can lead to wrong effects. 

Vessel height, m (.b) US dollars Material factors 1 Pressure factors ... 

Figure 6.5a, b. Vertical pressure vessels. Time base mid-2004. Purchased cost = (bare cost from figure) x Material factor x Pressure factor... 

Bare vessel cost (Figure 6.5a) 21,000 material factor 1.0, pressure factor 1.1... 

The basis of the F El is a Material Factor (MF). The MF is then multiplied by a Unit Hazard Factor, F3, to determine the F El for the process unit. The Unit Hazard factor is the product of two factors which take account of the hazards inherent in the operation of the particular process unit the general and special process hazards, see Figure 9.2. 

The material factor is a measure of the intrinsic rate of energy release from the burning, explosion, or other chemical reaction of the material. Values for the MF for over 300 of... 

Some typical material factors are given in Table 9.4. 

STATE OF OPERATION — DESIGN — STARTUP —NORMAL OPERATION—SHUTDOWN BASIC MATERIALS) FOR MATERIAL FACTOR ... 

MATERIAL FACTOR (See Table 1 or Appendices A or B) Note requirements when unit temperature over 140 °F (60 °C) ... 

The first step is to calculate the Damage factor for the unit. The Damage factor depends on the value of the Material factor and the Process unit hazards factor (F3 in Figure 2). It is determined using Figure 8 in the Dow Guide. 

The process is first divided into a number of units which are assessed individually. The dominant material for each unit is then selected and its material factor determined. The material factor in the Mond index is a function of the energy content per unit weight (the heat of combustion). 

The material factor is then modified to allow for the effect of general and special process and material hazards the physical quantity of the material in the process step the plant layout and the toxicity of process materials. 

Unit consider the total plant, no separate areas, but exclude the main storages. Material factor for ammonia, from Dow Guide, and Table 9.3. 

Note Hydrogen is present, and has a larger material factor (21) but the concentration is too small for it to be considered the dominant material. 

In 1964 the installed cost for each extruder and its accessory equipment was given as 90,000.25 The indirect costs increase the cost for solids-handling equipment an average of 29%. This gives a bare module cost of 1,180,000 for all 9 extruders and accessories in 1968. No bare module factors are given for extruders. However, an extruder is really a polymer pump, and for pumps and compressors the bare module factor is around 3.25 and the material factor for stainless steel is 2.0. A back calculation gives a 1968 F.O.B. cost of 540,000. 

In some cases a material factor was not given for aluminum. In these cases, a material factor of 1.50 was assumed. Where two figures were given for offsite calculations, the lower one was used, since this is to be a relatively small plant. 

Table 9E-9 lists unit operations in the polystyrene plant. The highest temperature is 400°F, in the extruder. From this and Figure 9-5, a temperature factor of 0.04 is obtained. There are no high pressures except in the extruder, and its value is unknown. The pressure factor will be assumed to be zero. Stainless steel is used, so the material factor is 0.2. From Equation 2 a complexity factor of 3.48 can be calculated. A direct process investment cost of 350,000 per functional unit is obtained from Figure 9-7. This means that the cost of constructing the plant when the Engineering News Record Construction Index (ENRCI) is 300 would be 3,150,000. This will be updated to 1960 when the ENRCI was 350, and then the CEPI will be used to obtain the cost in 1974. The resultant cost in 1974 is... 

The procedure begins with a material factor that is a function only of the type of chemical or chemicals used. This factor is adjusted for general and special process hazards. These adjustments or penalties are based on conditions such as storage above the flash or boiling point, endo- or exothermic reactions, and fired heaters. Credits for various safety systems and procedures are used for estimating the consequences of the hazard, after the fire and explosion index has been determined. 

The next step is to determine the material factor (MF) for use in the form shown in Figure 10-3. Table 10-1 lists MFs for a number of important compounds. This list also includes data on heat of combustion and flash and boiling point temperatures. The additional data are also used in the computation of the Dow F EI. A procedure is provided in the complete index for computing the material factor for other compounds not listed in Table 10-1 or provided in the Dow reference. 

Compound Material factor Heat of combustion (Btu/lb x 10 1 2 3 4) Flash point (°F) Boiling point <°F)... 

STATE OF OPERATION DESIGN START UP X NORMAL OPERATION SHUTDOWN BASIC MATERIAL(S) FOR MATERIAL FACTOR Butadiene ... 

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