Efficiency term

Fhe Stag C Separation Factor. The stage separation factor, in all probabiUty, is appreciably different from the ideal-point separation factor because of the existence of four efficiency terms ... 

The polarisation and cathode efficiency terms in equation 12.12 cannot be altered in practice to improve thickness distribution, as they tend to be decided by overriding considerations. It is usual to accept the distribution obtained without special precautions as being the best commercial solution, although the average thickness needed to achieve the necessary minimum... 

The highly interactive nature of the balance and equilibria equations for the distillation period are depicted in Fig. 3.66. An implicit, iterative algebraic loop is involved in the calculation of the boiling point temperature at each time interval. This involves guessing the temperature and calculating the sum of the partial pressures, or mole fractions. The condition required is that Zyi + yw = 1. The iterative loop for the bubble point calculation is represented by the five interconnected blocks in the lower right hand corner of Fig. 3.66. The model of Prenosil (1976) also included an efficiency term E for the steam heating, dependent on liquid depth L and bubble diameter D. 

Why must we include an efficiency term in the rate equation describing the effect of the initiator on the kinetics of polymerization What does this term account for ... 

The absorption efficiency term allows estimation of the effective dose or the amount of pollutant which crosses the membrane of the exposed tissue (e.g., the lung) and reaches a target organ (e.g., the liver). For many pollutants this type of metabolic data is not available and consequently 100% absorption is a common preliminary assumption in exposure assessments. For well-studied substances such as radionuclides, a methodology for calculation of target organ doses has been developed for bone marrow, lungs, endosteal cells, stomach wall, lower intestine wall, thyroid, liver, kidney, testes and ovaries as well as for the total body. 

The detection performance of an LIF photometric device is governed by the emission filter(s), excitation filter(s), detector type, the excitation source and the detection scheme. The selection of optical elements and device configuration as it relates to the detection performance is further described by expanding the collection efficiency term in Equation 11.3 ... 

The slope of the lines presented in Figure 5 is defined as k(q/v). The q/v term defines the turnover of the tank contents or what is commonly referred to as the retention time. When q is increased, the liquid contacts the carbon more often and the removal of pesticides should increase, however, the efficiency term, k, can be a function of q. As the waste flow rate is increased, the fluid velocity around each carbon particle increases, thereby increasing system turbulence and compressing the liquid boundary layer. The residence time within the carbon bed is also decreased at higher liquid flow rates, which will reduce the time available for the pesticides to diffuse from the bulk liquid into the liquid boundary layer and into the carbon pores. From inspection of Table II, the pesticide concentration also effects the efficiency factor, k can only be determined experimentally and is valid only for the equipment and conditions tested. 

FIGURE 14-28 Calculated mass scattering efficiency term (oR,1/un) as a function of wavelength for 0, 40, and 97% RH. Particle dry radius taken to be 0.096-yu.m (NH4)2S04 (adapted from Nemesure et al., 1995). 

Both horizontal and vertical cross-flow separators require spreaders and collectors to uniformly distribute water flow through the plates For this reason, it is suggested that Eq. 8 be modified to indude a 75% spreader efficiency term ... 

In the past, several terms have been coined to describe the retention efficiency of the filter system beta value, microbiological safety index, reduction ratio, and titer reduction ratio [64,68,72], The log reduction value (LRV) is a filter retention efficiency term that is the logarithm to the base of 10 of the ratio of the number of organisms in the challenge suspension to the number of organisms in the filtrate. 

This tray efficiency term (C) deserves further examination. It is derived from an empirical equation presented in Ref. Al, p. 183. The correlation accounts for the individual geometry of the sieve plate and other essential operating variables. It takes the form ... 

This efficiency term (C) is potentially very comprehensive as it accounts for the key factors in plate hydraulic design, e.g. hole diameter, liquid depth, vapour velocity and open area. 

Here, Ep>Spec is the total energy for pumping the diluate, the concentrate, and the electrode rinse solution through the stack per unit diluate water, keff is an efficiency term for the pumps, QF, and Qe are the volume flow rates of the diluate, the concentrate, and the electrode rinse solution through the stack. 

A generalization on the application of an AOT can never be made. Each effluent must be previously characterized, and treatability tests at the laboratory scale must be performed to choose the most appropriate method in economical and efficiency terms. It is important to evaluate the existing options to choose the most adequate. A knowledge of the kinetics, with establishment of the limiting step and limiting reagent(s), and a comparison with other conventional treatments should be available before applying... 

If the retention times of the sample components are adequate, partial separation of the bands is apparent, but the bands are relatively broad (Fig. 1.18D), the resolution can be possibly improved by increasing the efficiency term contribution, i.e.. by increasing the plate number of the chromatographic column. 

The resolution consists of two terms, the selectivity term, with the relative difference of the mobilities, and the efficiency term, the square root of the mean plate number. It must be pointed out that the plate height, H, on which this plate number is based consists of all the contributions to peak broadening. 

Having just worked through the industrial yield example allows one to visualize another important aspect. It tells us the fraction of the converted starting material that is product, a sort of efficiency term for avoidance of byproducts. For this reason, selectivity or efficiency are often used synonymously with industrial yield. From sustainability, economic, and emission control points of view, the selectivity of a process is a very important concept, and well worth the research effort toward maximization. 

Equipment design, as discussed in the preceding section, requires preliminary evaluation of column efficiency. There is a close conphng between geometry and efficiency. Several different efficiency terms will be nsed for tray columns, bnt the one nltimately needed for design is overall column efficiency ... 

This efficiency term actually comprises a number of component efficiencies, and for meticulous work, it may be necessary to take them into account. Methods given in Chapter 12 can be used for this purpose, since the mass transfer mechanisms for absorption and stripping are the same as those for distillation. 

Several different efficiency terms will be used in this section, and the one ultimately needed for design is overall column efficiency ... 

Here 4 is the current utilization, q is an efficiency term and n is the number of cell pairs in a stack the subscripts w, m and s are referring to efficiency losses due to water transfer, conductivity of stack components and membrane selectivity. 

The resolution, Rs, of two neighbouring peaks in an MEKC separation can be calculated as a product of an efficiency term, a selectivity term and a retention term ... 

Reduce, reuse, recycle, up-cycle, and efficiency terms are already placed into the textile and energy hterature, textile production and apphcations stages, and textile-using lifetime by consumers and even recycling stages. 

With good design and operation, fuel-fired furnace efficiencies of 60% or higher can be had, depending much on process temperature. Efficiency here is the ratio of heat input into the load/hr to the gross heat released by the fuel used/hr. The Glossary compares efficiency terms. When comparing costs, always ask for clarification as to what is meant by efficiency. ... 

The value of m is dependent upon the pH of the solution. If m 0, then redox reaction involves the incorporation and expulsion of protons during the redox reaction and this can be measured by a pH-sensitive bismuth oxide ring electrode [18,19]. In the special case when the ring electrode is a potentiometric sensor with a low exchange current density, such as the bismuth oxide sensor for pH [18,19], the ring electrode reaction does not significantly perturb the radial concentration profile of the disc product across the ring, and a different collection efficiency, termed the detection efficiency. 

---