Feasible designs

An analysis of this type is appropriate during the preliminary design stage when process alternatives may have to be screened economically, or when it is necessary to determine a feasible design as the basis for equipment trials and/or final designs. 

Wallace, S., Feasibility, Design Criteria, and O M Requirements for Small Scale Constructed Wetland Wastewater Treatment Systems, IWA Publishing, London, 2006. 

Bi in Figure 12.20. This means that there is some combination of settings for the reflux ratio and reboil ratio that will allow the section profiles to intersect and become a feasible column design. By contrast, bottoms composition B2 shows an operation leaf that does not intersect with the operation leaf of distillate D. This means that the two products D and B2 cannot be produced in the same column, and the design is infeasible. No settings of reboil ratio or reflux ratio can make the combination of B2 and D a feasible design. 

The size and shape of the middle section operation leaf depends on the location of the difference point, which in turn depends on the flowrate of entrainer. There will be a minimum flowrate of entrainer for feasible design. Above the minimum flowrate, the actual flowrate of the entrainer is an important degree of freedom for optimization. 

Discuss the relative merits of the tubular and planar SOFC designs. With special reference to the electroceramics involved and to their processing, sketch a feasible design for a planar SOFC stack running at 900 °C. 

The strategy of design, illustrated in Figure 8.1, consists of an evolutionary search of the feasible design space by means of a systematic combination of thermodynamic analysis, computer simulation and only limited experiments. The approach is generic for developing a RD process, at least for similar systems. The first element of similarity is the existence of an equilibrium reaction with water as product This raises the problem of possible aqueous-phase segregation. The second element is the similarity of thermodynamics properties over a class of substrates. However, while the fatty acids and fatty esters manifest a certain... 

Given a description of a multiple-unit process, determine the number of degrees of freedom, identify a set of feasible design variables, and if there are cycles in the flowchart, identify reasonable tear stream variables and outline the solution procedure. Draw a sequential modular block diagram for the process, inserting necessary convergence blocks. 

In order to obtain a solution in reasonable time, it is extremely important that the design algorithm not take too many iterations to identify an outer approximation adequate to force a feasible design. One method of tackling this is to use the method of Mayne el al. (1990), in which previous local maximizers are... 

In order to obtain a feasible design the following steps are performed i) calculate for the separation ethanol/water/l-pentanol (DISTIL), ii) estimate the number of... 

Full factorial designs can be used in quantitative method validation. With very few factors this is a feasible design. A simple way to display the experiment necessary for the validation is to display the assay runs in a table or matrix. For instance, suppose a method is run on two different machines and the goal is to assess intermediate precision components. We have the random effects of operator and day and a fixed... 

Use a Depth-First Approach, The point here is to generate an initial flowsheet dial later can be optimized and to avoid backtracking. A great deal is learned on completing an initial feasible design even if it is far from optimal. 

Fig. 55. Effect of varying rotor diameter in brushless DC motors based on permanent magnets, (a) Situation for ferrite magnets under various constraints discussed in the main text. The arrow indicates increasing electric loading Q. (b) Envelope of feasible designs (hatched area) based on different permanent magnet materials. The arrows L and BH indicate increasing inductance (L) and increasing (BH)msi%, respectively. (After Howe et al. 1987.)...

The innovation of sustainable processes begins at the laboratory scale. The investigation of the feasible design space by simulation can reduce tremendously the experimental effort. We may speak about computer-aided experimental research. 

Feasible design space in term of temperature, pressure and concentrations... 

A set of feasible design variable specifications is Variable Specification Number of Variables... 

FKvURE 2.12 RCM for the benzene/p xylene/toluene system at P = 1 atm widi a possible feasible design for an infinite reflux column. 

Try this for yourself Reproduce the RCM in Figure 2,12 with DODS-ProPIot using the given parameters. Try generating another RCM at different pressures and find other feasible design solutions. 

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