Design measures

Phenol and alkenes react quite exothermically. The reaction between 1 mole of phenol and 1 mole of isobutylene to yield 1 mole of / -Z fZ-butylphenol PTBP Hberates approximately 79.8 kj /mol (19.1 kcal/mol) (24). In an adiabatic system, this reaction, if started at 40°C, would result in a reaction product at about 250°C. Temperatures above 200°C are considered unacceptably high in the reactor so design measures are employed to keep the temperature down. 

Despite the use of explosion-pressure-resistant equipment for the full explosion pressure or other design measures outlined later, everything possible must be done to prevent effective ignition sources, because loss of product and interruption of production are equally undesirable. 

Comparison of E] q)losion Protection Design Measures In Table 26-24, comparison is made of the explosion protection design measures of containment, explosion venting, and explosion suppression. Regarding the effectiveness of the different explosion design measures, all three techniques are equal if the design of these measures is performed properly. 

TABLE 26-24 Comparison of Explosion Protection Design Measures... 

Table 12.10 Design measures to reduce leaks from pipework...

Most of the published evidence suggests that marine fouling cover— particularly where it is continuous and well established — reduces corrosion rates of steels . Indeed, 35%o seawater is by no means the most corrosive of saline environments towards steel. Brackish water, as found in estuarine or certain other coastal areas, is considerably more aggressive towards steel, and careful design measures should be taken to ensure that effective corrosion control is achieved in such circumstances. 

The introduction of changes in the gas flow pattern of the unit could provide a means for improvement in both, single and two-reactor systems. It is important to keep in mind that in counter-current designs measures have to be taken to prevent hot spots within the reactor bed and to improve vapor-liquid contact. 

Bartknecht, W., Prevention and design measures for protection against dust explosions, in Industrial Dust Explosions (K. L. Cashdollar and M. Hertzberg, eds.) ASTM tech. pub. 958, pp. 158-190 (1987)... 

The additional measures can be divided into preventive measures to prevent an uncontrolled reaction and design measures to mitigate unacceptable consequences of a runaway reaction. Depending on the circumstances of each individual case the following alternatives or a combination thereof can be considered ... 

Pressure resistant construction or equipment protected by pressure relief devices are considered highly reliable where design measures are adopted to prevent unacceptable consequences of a runaway reaction. Design measures, especially the provision of pressure relief, may be appropriate and also required when a complete and reliable evaluation of deviations, their causes and consequences cannot be achieved. This can happen as a result of the complexity of the contributing causal chains. 

Risk reduction/control is primarily accomplished through design measures, SOPs, and training. 

Does it have aspects of design, measurement, and manufacturing control ... 

One should investigate whether certain design measures, such as cladding, reinforcement, or higher corrosion-allowance will improve the safety. 

Traditionally, risk is defined as the product of the severity of a potential incident by its probability of occurrence. Hence, risk assessment requires the evaluation of both the severity and the probability. Obviously, the results of such an analysis aid in designing measures for the reduction of the risk (Figure 3.1). The question that arises now is What do severity and probability mean in the case of thermal risks inherent to a particular chemical reaction or process ... 

If necessary one can easily extend the scheme by an additional factor. In principle, all the previous designed measurements must now be repeated with each level of the new factor. But one should not forget to randomize the order of experiments. In this way one quickly constructs a complete 2"+1 factorial design. 

Using this approach, we can describe any experimental design by the function q(y/), called the design measure or probability measure. This function is differentiable ... 

Many valuable records regarding the Miyagi Offshore Earthquake will become important resources for designing measures against earthquake hazards in the future. 

HAZOP and What-If reviews are a basically a communication exercise. Information is presented, discussed, analyzed and recorded. Specifically the safety aspects are identified, to determine if adequate design measures have be taken to prevent major accidents. Communication and evaluation are the prime facets of the procedures. 

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