Special Design Features

This process uses propylene carbonate as a physical solvent to remove CO2 and H2S. Propylene carbonate also removes C2+ hydrocarbons, COS, SO2, CS2, and H2O from the natural gas stream. Thus, in one step the natural gas can be sweetened and dehydrated to pipeline quality. In general, this process is used for bulk removal of CO2 and is not used to treat to less than 3% CO2, as may be required for pipeline quality gas. The system requires special design features, larger absorbers, and higher circulation rates to obtain pipeline quality and usually is not economically applicable for these outlet requirements. 

Unique system characteristics and special design features, e.g., corrosion, foaming, chemical reaction, and fouling, and designs to overcome such problems. 

This behavior is particularly relevant with push-fit assemblies and bolted joints that rely on maintaining their load under constant strain. Special design features or analysis may be required to counteract excessive stress-relaxation. 

The special design features for preventing electrostatic ignitions are described in the following paragraphs. 

All electrical devices are inherent ignition sources. Special design features are required to prevent the ignition of flammable vapors and dusts. The fire and explosion hazard is directly proportional to the number and type of electrically powered devices in a process area. 

Trevor Kletz21 and Walter B. Howard22 have emphasized the special design features for safer plants. The following recommendations also include design features from our own experiences ... 

There are many types of mass spectrometer, each having special design features, some offering very sophisticated modes of analysis and these details will not be described here. Rather, the fundamental principles and instrumental aspects associated with the technique in general are covered. More detailed information is available in specialist books or instrument manufacturers publications. 

LPG vessels may be directly buried below grade or mounded above grade to reduce exposure to an external fire. Both of these methods require special precautions, careful preparation, and special design features, since they introduce other substantial hazards. These hazards include undetected corrosion, undetected leaks, and the potential for mechanical damage when the vessel is unearthed for inspection. 

The pump types listed in Table 2 have special design features and shall be furnished only if specified by the purchaser and if the manufacturer has proven experience for the specific application. Table 2 lists the features requiring special consideration for these pump types and shows in parentheses the relevant clause(s) of this International Standard. 

Table 2 — Special design features of particular pump types...

The initiator core (CD) may be as small as an atom or as large as a molecule. It may be homogeneous with the other dendrimer components or it may contain special design features (e.g., metal atoms, chromophores, etc.) that differentiate it from the dendrimer interior thus making it heterogeneous. 

Choice of equipment for the processing line is very important for the production of margarines. For each piece of equipment in the production line, special design features have to be considered for various margarine types to ensure that the complete processing line has all the necessary capabilities. 

Special design features in the circulating system minimize the hazard... 

Of some interest are also so-called steam-gas generators that produce steam-gas mixtures with high pressures and temperatures. They may have output capacities and other operating parameters that are very similar to those of the traditional steam generators. But they have a number of special design features that make t lore economic, e.g. small dimensions and weight, also insignificant amount of metal required ir construction. 

CEA and TECHNICATOM (France) have about 200 reactor-years of experience from propulsion and small experimental reactors. Special design features for a future small reactor are formulated as follows ... 

For reactors equipped with vessel closure plugs to retain the fuel in position, special design features should be provided to ensure that the probability of ejection of the closure plug is low. In the absence of such special features, the consequences of the failure or the ejection of a single closure plug should be evaluated as for a missile. 

The probability of a control rod being ejected may be reduced in some reactor types by providing special design features. These features should be confirmed by test or by analysis to demonstrate that they have the capability to retain the control rod and drive assembly in the event of a failure of the travel housing for a control rod. 

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