Primary design

Part/Subsystem number — Primary design responsibility... 

Low concentrations of oil can be removed by dissolved air flotation (DAF). In this process, an effluent recycle is pressurized in the presence of excess air, causing additional air to go into solution, in accordance with Henry s Law. When this water is discharged to the inlet chamber of the flotation unit at close to atmospheric pressure, the dissolved air comes out of solution in the form of tiny air bubbles which attach themselves to and become enmeshed in suspended solids and oil globules. The primary design criteria is the air/solids ratio, which is defined as the mass of air released divided by the mass of solids fed. Sufficient air must be released to capture the solids in the influent wastewater. The performance of DAF for the treatment of several... 

An adiabatic process is never fully attained but can be closely approached for many processes and is the primary design basis for most positive displacement compression equipment. 

Concrete exposed to deicer salts, or to a marine environment is subjected to chloride and sodium loading. The ability of concrete to resist the penetration of chlorides and sodium is a primary design consideration in marine or cold environments. The ingress of chlorides into concrete is a major problem due to chloride-induced corrosion of the reinforcing steel and deicer salt scaling [a process by which a thin layer (< 1 mm) of concrete deteriorates from the surface of the concrete]. The penetration of sodium from sea water or deicer salts is generally... 

PRK is the primary design criterion for landfill covers that are expected to limit and control the amount of precipitation that enters the waste of the landfill. As a result, the primary focus of model... 

Extension of the Kunii-Levenspiel bubbling-bed model for first-order reactions to complex systems is of practical significance, since most of the processes conducted in fluidized-bed reactors involve such systems. Thus, the yield or selectivity to a desired product is a primary design issue which should be considered. As described in Chapter 5, reactions may occur in series or parallel, or a combination of both. Specific examples include the production of acrylonitrile from propylene, in which other nitriles may be formed, oxidation of butadiene and butene to produce maleic anhydride and other oxidation products, and the production of phthalic anhydride from naphthalene, in which phthalic anhydride may undergo further oxidation. 

The primary design consideration at any oil, gas or related facility should be the protection of employees and the general public from the effects of an explosion or fire. In all cases highly populated occupancies should be located as far as practical upwind of the process or storage areas. Where this cannot be practically... 

The primary design parameter to be considered in hydrolysis is the half-life of the original molecule, which is the time required to react 50% of the original compound. The half-life is generally a function of the type of molecule hydrolyzed and the temperature and pH of the reaction. Figure 13 shows the elfect of pH and temperature for the degradation of malathion by hydrolysis [11]. 

As discussed in Subheading 1., the primary design criterion is often based on either similarity or diversity. Quantifying these measures requires that the compounds are represented by numerical descriptors that enable pairwise molecular similarities or distances to be calculated or that allow the definition of a multidimensional property space in which the molecules can be placed. 

Problem Statement and Design Criteria. Propose a suitable replacement for enamel for use in coating a human tooth. The primary design criteria are ... 

Although the capacity of this water-polishing device at ultra-high water cuts was the primary design criterion, several other factors had to be considered. 

Because of continuing problems with wash tanks as water separation equipment, a commitment was made to design a high-rate separator based on the API model separator. The primary design criterion was its effectiveness at rates of more than 25.000 B/D (3975 m3/d). Secondary criteria were ease of construction, durability, and low capital costs. 

A cross-sectional view of a mechanical-draft tower is illustrated in Figure 4.16. The primary design elements are numbered in this figure and are summarized below ... 

In the primary design, following that of the solid-gas impinging stream contactor used in earlier investigations on RTD and hydraulic resistance etc., the two nozzles are placed in the middle of the gas conduits (Point A, represented by the solid lines in Fig. 

The optimum mixture ratio for a given propellant combination is in turn influenced by the other primary design parameters, chamber pressure and expansion ratio. 

Before the 1950s, column calculations were performed by hand. Although rigorous calculation procedures were available, they were difficult to apply for all but very small columns. Shortcut methods were therefore the primary design tool. Rigorous procedures were only used for small columns or for final design checks. Inaccuracies and uncertainties in the shortcut procedures were usually accommodated by overdesign. 

Figure 10.2 shows the primary design output from ROSA. The primary design output includes design inputs as well as calculated outputs. Inputs included are ... 

Figure 10.2 Primary design output of Dow Water and Process Solutions ROSA design program.

Figure 10.13 Primary design input screen of Hydranautics IMS Design program.

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