Design objective

When the process is operating normally, no alarms should be triggered. Within the electric utihty industry, this design objective is known as darkboard. Application of darkboard is especially important in batch plants, where much of the process equipment is operated intermittently. 

The design objectives of the analyst and the production line engineer are generally quite different. For analysis the primary concern is typically resolution. Hence operating conditions near the minimum value of the HETP or the HTU are desirable (see Fig. 16-13). 

The results of the Flixborough investigation made it clear that the large inventory of flammable material in the process plant contributed to the scale of the disaster. It was concluded that limitations of inventory should be taken as specific design objectives in major hazard installations. It should be noted, however, that reduction of inventoiy may require more frequent and smaller shipments and improved management. 

Shorter center distance is a very practical design objective. Such a design uses space economically and allows for a stable operation. In general, center distances are limited by the physical dimensions of the sheaves, or the minimum angle of 6, i.e.. 150". Maximum drive centers are limited only by available V-belt stocked lengths. 

An in-depth understanding of structure-property relationships is perhaps the most important concern for the urethane formulation chemist. Material design objectives often go far beyond physical property requirements and may also include considerations like processing characteristics (i.e., compatibility, reactivity,... 

According to Cano-Ruiz and McRae, process design as a part of process development starts with problem framing. At this stage, the concept definition, scope of analysis, design objectives, constraints, evaluation and interruption criteria have to be determined. They argued that framing decisions are often made implicitly, whereas the critical importance... 

A good example of a reactive modifier which has been used (14) to enhance properties of polyolefins is maleic anhydride (MA). The formation of maleic adduct in polypropylene (PP), for example, can be used to effect several modifications e.g. to improving hydrophilicity, adhesion and dyeabflity. Moreover, the polymer-maleic adduct has an availabla additional functionality to effect other chemical modifications for achieving the desired material design objectives. Reactions of MA with polymers in solution are described in the patent literature (15). 

The refineries were almost exact copies of each other and were originally designed to produce only transportation fuels. The specific design objectives were 37... 

Short-chain olefins are not refined and the gaseous LTFT products are employed as fuel gas. Production of this fraction is limited by Co-LTFT synthesis, and with the product being less olefinic than iron-based Fischer-Tropsch syncrude, less benefit would be derived from the inclusion of an olefin oligomerization unit. Furthermore, adding complexity would go against the design objectives of the SMDS process. 

It is of interest to analyze the paradigm shift caused by the SMDS process in context of the original Shell design objectives (refer to Section 18.8) and the current situation. 

The design objectives for the SMDS process were developed to exploit small or remote gas fields where the cost of liquefied natural gas production or a gas pipeline system is not warranted. In many of the present GTL applications this is not... 

The design objective is to prevent the buildup of charges on a product (liquid or powder) as well as on surrounding objects (equipment or personnel). For every charged object there exists its oppositely charged counterpart. Three methods are used to achieve this objective ... 

When designing objects inside the software, you have a choice about whether to reify abstract objects and actions—that is, represent them directly as software objects—or just... 

Cook94] Cook, S., and J. Daniels. 1994. Designing Object Systems Object-Oriented Modeling with Syntrophy. Englewood Cliffs, N.J. Prentice Hall. 

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